Study reference

Study characteristics

Patient characteristics

Intervention (I)

Comparison / control (C)

Follow-up

Outcome measures and effect size

Comments

Ozdemir 2016

SR and meta-analysis of RCTs and cohort study’s

Literature search up to September 2014

A: Joshipura 2009 (22)

B: Sefr 2003 (32)

C: Vijayaragnavan 2014 (38)

D: Wallace 1997 (39)

E: Warle 2013 (40)

F: Karagulle 2008 (25)

G: Eryilmaz 2012 (6)

H: Dexter 1999 (18)

I: Ekici 2009 (19)

J: Sood 2006 (34)

K:Umar 2013 (37)

L:Topal 2011 (35)

M: Bogani 2014(14)

N: Celik 2010(16)

O:Chok 2006(17)

P:Hasukic 2005(21)

Q:Morino 1998(27)

R: Sandhu 2009 (30)

S: Sarli 2000(31)

T: Koc 2005(26)

U: Kanwer 2009 (24)

V: Singla 2014 (33)

W: Barcynski 2002 (2)

X: Kandil 2010 (23)

Y: Yasir (41)

Z: Emad Esmat

AA: Perrakis

Study design: RCT

Setting and Country:

A: India

B: Chech Republic

C: India

D: UK

E: the Netherlands

F: Turkey

G: Turkey

H: UK

I:Turkey

J: India

K: India

L: Turkey

M: Italy

N: Turkey

O: China

P: Bosnia

Q: Italy

R: Thailand

S: Italy

T: Turkey

U: India

V: India

W: Poland

X: Egypt

Y: India

Z: Egypt

AA: Greece

Inclusion criteria SR: RCT and cohort studies (for our analysis only RCT) comparing low versus standard pressure PNP

23 studies included

Important patient characteristics at baseline:

N, mean age

A: 26, 57 years

B: 30, 54 years

C: 43, 44.5 versus 40

D: 40, 58 years

E: 20, 51.6 versus. 50.7

F: 45, 47 years

G: 43, 51 years

H: 23, 52 years

I:52, 50.7 versus 51.6 years

J:9, (25-60 yr)

K: unknown

L: 60, 42 years

M:42. 44 versus 49yr

N: 64, 44

O: 40, 47 years

P: 50, 43 years

Q:52, unknown

R:140, 55 years

S:90, 49 versus 47

T: 53, 47 years

U: 60, age not stated

V:100, 50 VS 53YR

W: 20, 46 year

X: 116, 42 year

Y: 100, unknown

Z:71, 47.8 versus 46.6

AA:40. 55 versus 58.50

Sex:

A: 42.3% female

B: 76.7% female

C: 26/43 female

D: 75% female

E: 50% female

F: 84.1% female

G: 60.5% female

H: 65% female

I: 84% female

J: 55% female

K: unknown

L: 21.7%

M:100% female

N: 100% female

O: 60% female

P: 90% female

Q: unknown

R: 79.3% female

S:73% female

T: 82% female

U: not stated

V:68% female

W: 55% female

X: 62% female

Y:unknown

Z:73% female

AA:75% female

Describe intervention:

A: laparoscopic cholecystectomy low pressure 8 mm Hg (trocar insertion at 12 mm Hg)

B: laparoscopic cholecystectomy low pressure 10 mmHg

C: laparoscopic cholecystectomy low 8 mmHg

D: laparoscopic cholecystectomy low pressure 7.5 mmHg

E: laparoscopic donor nephrectomy low pressure 7 mmHg

F: laparoscopic cholecystectomy low pressure 8 mm Hg

G: laparoscopic cholecystectomy low pressure 10 mmHg

H: laparoscopic cholecystectomy low pressure 7 mmHg

I: laparoscopic cholecystectomy low pressure 7 mmHg

J: laparoscopic removal pheochromocytoma low pressure 8-10 mmHg

K: laparoscopic cholecystectomy low pressure 8-10 mmHg

L: laparoscopic cholecystectomy low pressure 10 mm Hg

M: laparoscopic hysterectomy low 8 mmHg

N: laparoscopic cholecystectomy low pressure 8 mm Hg

O: laparoscopic cholecystectomy low pressure 7 mm Hg

P: laparoscopic cholecystectomy low pressure 7 mm Hg

Q: laparoscopic surgery low pressure 10 mmHg

R: laparoscopic cholecystectomy low pressure 7 mm Hg

S: laparoscopic cholecystectomy low pressure 9 mm Hg

T: laparoscopic cholecystectomy low pressure 10 mmHg

U: laparoscopic cholecystectomy low pressure 10 mm Hg

V: laparoscopic cholecystectomy low pressure 7-8 mm Hg

W: Laparoscopic cholecystectomy. Low pressure 7 mm Hg

X: low pressure cholecystectomy 8 or 10 mmHg

Y: Laparoscopic cholecystectomy with low pressure (8mmHg)

Z: Laparoscopic cholecystectomy with low pressure 10 mmHg

AA: Laparoscopic cholecystectomy with low pressure 8 mmHg

Describe control:

A: laparoscopic cholecystectomy standard pressure 12 mm Hg

B: laparoscopic cholecystectomy standard pressure 15 mmHg

C: laparoscopic cholecystectomy standard pressure 12 mmHg

D: laparoscopic cholecystectomy standard pressure 15 mmHg

E: laparoscopic donor nephrectomy standard pressure 12 mmHg

F: laparoscopic cholecystectomy standard pressure 12 mmHg AND 15 mmHg

G: laparoscopic cholecystectomy standard pressure 14 mmHg

H: laparoscopic cholecystectomy standard pressure 15 mmHg

I: laparoscopic cholecystectomy standard pressure 15 mmHg

J: laparoscopic removal pheochromocytoma standard pressure 15 mmHg

K: laparoscopic cholecystectomy standard pressure 11-13 mmHg versus 14

L: laparoscopic cholecystectomy standard pressure 13 mm or 16 mm Hg (high pressure!)

M: laparoscopic hysterectomy standard 12 mmHg

N: laparoscopic cholecystectomy standard pressure 12 or 14 mm Hg

O: laparoscopic cholecystectomy standard pressure 12 mm Hg

P: laparoscopic cholecystectomy standard pressure 14 mm Hg

Q: laparoscopic surgery standard pressure 14 mm Hg

R: laparoscopic cholecystectomy standard pressure 14 mm Hg

S: laparoscopic cholecystectomy standard pressure 13 mm Hg

T: laparoscopic cholecystectomy standard pressure 15 mm Hg

U: :laparoscopic cholecystectomy standard pressure 14 mm Hg

V: laparoscopic cholecystectomy standard pressure 12-14 mm Hg

W: Laparoscopic cholecystectomy. Standard pressure 12 mm Hg (n = 10).

X: standard pressure cholecystectomy 12 or 14 mmHg

Y: Laparoscopic cholecystectomy with normal pressure (14mmHg)

Z: Laparoscopic cholecystectomy with standard pressure 14 mmHg

AA: Laparoscopic cholecystectomy with standard pressure 15 mmHg

End-point of follow-up:

A: 11 months

B: surgery

C: 24 hours

D: 6 days

E: 7 days

F: 30 days

G: 24 hours

H: 7 days

I: surgery

J: return to normal activity

K: surgery

L: 24 hours

M: 30-40 days

N: 24hr

O: 4 weeks

P: 4 weeks

Q: 72 hours

R:24hr

S:48hr

T:24hr

U:24hr

V:24hr

W: 7 days

X: 10days

Y: 1 day

Z:48hr

AA: 7 days

For how many participants were no complete outcome data available?

(intervention/control)

A: Postrandomisation dropouts: zero (0%). 4 patients conversion to normal pressure because of difficulty in performing safe dissection

B: Postrandomisation dropouts: zero.

C: 1 patient withdraw after surgery (standard group)

D: Postrandomisation dropouts: zero.

E: no dropouts

F: Postrandomisation dropouts: one (2.2%) (low pressure group, conversion to open surgery). Successful completion of low pressure laparoscopic cholecystectomy: not stated

G: Postrandomisation dropouts: not stated.

H: Postrandomisation dropouts: three (13%)

I: 14 dropouts due to protocol violations. 1 was increased to normal pressure.

J: no

K: unknown

L: Successful completion of low pressure laparoscopic cholecystectomy: not stated. Postrandomisation dropouts: not stated.

M:3 patients lost to follow up.

N: Successful completion of low pressure laparoscopic cholecystectomy: 20/23 (87.0%). Postrandomisation dropouts: four (6.3%).

O: Postrandomisation dropouts: zero.

P: Postrandomisation dropouts: not stated

Q:no dropouts stated

R: Postrandomisation dropouts: zero (0%). Reasons for postrandomisation dropouts: not stated. Successful completion of low pressure laparoscopic cholecystectomy: 68/70 (97.1%)

S: 4/94 withdrawn due to conversion

T: Postrandomisation dropouts: three (5.7%). Reason for postrandomisation dropout: conversion to open cholecystectomy (group not stated).

U: Postrandomisation dropouts: five (8.3%). Successful completion of low pressure laparoscopic cholecystectomy: 27/30 (90%)

V: no dropouts

W: no postrandomization dropouts

X: Postrandomisation dropouts: 16 (13.8%). Reasons for postrandomisation dropouts: The laparoscopic procedure was converted to open cholecystectomy (two), refused to give informed consent (one), history of upper laparotomy (three), Grade III by American Society of Anesthesiology (two), the laparoscopic procedure was converted from low to higher pneumoperitoneum pressure (four), and participants had cirrhotic liver (four).

Y: unknown

Z: postrandomization dropouts: 6 due to conversion to open, 11 due to conversion from low to normal pressure. 3 due to acute cholecystitis and 1 due to postoperative bile leakage.

AA: no postrandomization dropout

Outcome measure-1: Pain

A: overall pain: less pain in low pressure group at 4, 8 and 24 hours postoperative (all clinically relevant). 24h 1.1 versus 2.3 (p<0.001). more analgesic use (injection) in normal pressure group (0 versus 2, median) p= sign.)

B: X

C: analgesic requirements: 8mg versus 13 mg (p=0,001). Total number of demands 8 versus 18 (p=0.002).

Overall pain (median): postoperative pain scores lower at 0,4,8,24h. 0h 3 versus 5 p=0.003, 4h 2 versus 4 p=0.000 7h 2 versus 3 p=0.001 24h: 1versus 3 (p=0.002).

D:

Percentage of biliairy symptom score: less pain at 6h, 24h. 6h: 37 versus 51 p=0.04. 24h: 16 versus 43, p=0.01). not at 144 h.

no difference in morphine mg or analgesia requests

E: cumulative opiate use 32 versus 41 mg (p=0.604)

No difference at single time points (overall pain, superficial wound pain, deep pain, referred shoulder pain), only cumulative pain scores.

Exact numbers available in meta-analysis.

F: no patients needed additional analgesic administration.

G: X

H: X

I:X

J: X

K: X

L: X

M: abdominal pain no difference. Shouldertip-pain: lower for low pressure at 1 and 3 hr, not at 24hr, clinically relevant. Incidence of shouldertip pain higher in normal pressure (5% versus 36%) at 1hr and at 3 hr (10 versus 41%). Recue analgesic requirements did not differ

N: Overall pain:

no difference VAS 1-24 hr. no difference analgesic injection mg.

O: no difference in incidence in shouldertip pain.

Overall pain: No difference in VAS day 1 and 3, no difference in analgesic consumption

P:X

Q:X

R:analgesic consumption no difference.

Overall pain: VAS no difference. Shoulder and back pain no difference (scale 0-1-2).

S: incidence of shoulderpain different at 6,12,24,48 hr. not at 1,3 hours (less for low pressure). Postoperative iv ketoprofen requirements lower in low pressure in 24h postoperative. (27 versus 62 mg). Shoulder tip pain: VAS different at 12 and 24hr (3.5 versus 6 (from graph) and 0.5 versus 3.5 (from graph))

No difference in analgesia use.

T: Overall pain: mcgill score: 6h, 24h no difference. Overall pain: VAS 6h and 24hr no difference. No difference in analgesic use.

U: no difference in analgesic requirements.

Overall pain: VAS 6h no difference. VAS 12h 54 versus 62, sign however not clinically relevant. VAS 24h no difference.

V: more patients needing analgesia in normal pressure. Overall pain: Higher VAS in normal pressure, at all moments. However, not all clinically relevant.

Analgesic consumption only higher in normal pressure 3-4 hr and 9-12 hr post-OR

W: incidence shoulder tip pain 10% versus 24% (0.03).

Shoulder tip pain: VAS different at 24,48,72,96 hours (difference not clinically relevant). Not at 4,8,12 hr and 5,6,7 days. Analgesic consumption different at day 3 and 4.

X: Overall pain: lower pain with lower pressure at 12,14 hr and 3 days. Not at 7 and 10 days.

Y: 10% versus 28% shouldertip pain (p=0.001). VAS 4.2 versus 4.43 (p=0.039) at 4h, not clinically relevant. At 8h and 24h no difference.

Z: incidence shouldertip pain 16.2% versus 35.2% sign.

VAS (scale 1-6): no difference at 2 hr and 48. At 6hr 2.0 versus 3.0, 12h 3.0 versus 3.9, 24h 1.29 versus 2.5, all sign. More analgesic use in standard pressure. (total 100 mg versus 550 mg)

AA: no difference in pain score and analgesic consumption

Outcome measure-2: Pulmonary function

A: EtCO2, pCO2, pO2, blood gas analyses

pH, pCO2, HCO3-, BE no difference. pO2 sign difference at 30 min inflation (181.48 versus 206.27, p<0.001) and after deflation (231.69 versus 196.31, p<0.001)

B: pH, PaO2, PaCO2, HCO3-, BE no difference

C: PEFR (peak expiration flow rate) no difference

D: pCO2, EtCO2, median peak airway no difference. FVC and FEV1 no difference. PEFR recovery better at 6h, but not at 24h

E: minute ventilation, EtCO2 no difference. Respiratory rate at pneumoperitoneum phase 15 versus 13 (p=0.008) (not clinically relevant). PIP pneumoperitoneum phase 19 versus 21 (p=0.003) (not clinically relevant)

F: no differences in FVC, FEV1, FEV1/FVC, PEF, FEF.

G: no difference peripheral O2, EtCO2

H: X

I:X

J:X

K: EtCO2 difference between group 1 and 3 and group 2 and 3 all moments (between 2 and 3 only no significance 30 min after CO2 insufflation). All within normal limits

L: X

M:X

N:X

O:X

P:X

Q:X

R:X

S:X

T:X

U:X

V:X

W: X

X: X

Y:X

Z: X

AA: X

Outcome measure-3: Cardiac function

A: X

B: X

C: X

D: HR no difference. Cardiac index and stroke index: no significance difference but effect lasted longer (CI) and rise was slower (SI)

E: HR, MAP no difference

F: X

G: no difference HR, MAP,

H: HR, MAP no difference. Stroke volume and cardiac output: low pressure greater area under the curve (so larger stroke volume and cardiac output).

I: MAP no difference

J: HR no difference. MAP only difference at surgical manipulation tumor (114 versus 145), no difference at extubation afterwards.

K: HR difference from 10 min after CO 2 insufflation until 10 min after exsufflation in comparison between group 1 and 3 and 2 and 3.

Systolic blood pressure difference from 5 minutes after CO2 insufflation until end for comparison between group 1 and 3, for group 2 and 3 only 10 minutes after exsufflation.

MAP: between group 1 and 3 difference from 5 minute after CO2 insufflation until the end, between group 2 and 3 only 10 min after exsufflation. However, all within normal limits

L: X

M:X

N:X

O:X

P:X

Q:X

R:X

S:X

T:X

U: systolic, diastolic BP and HR no difference.

V:X

W: X

X:X

Y:X

Z: X

AA:X

Outcome measure-4: thromboembolic complications

A: no difference in 2D echocardiography and lower limb doppler findings in pre-operative and postoperative periods in either group

B: X

C: X

D: X

E: X

F: X

G: X

H: X

I: X

J: X

K: X

L: No difference in Hb, Htc, thrombocyte, leukocyte, erythrocyte, PT, aPTT, INR, electrolyte

no difference in trombo-embolic parameters (alpha-angle, reaction time, k-time, maximum amplitude) between low and normal pneumoperitoneum pressure. Between high and low: lower reaction time in high pressure, increased MA in high pressure compared to low pressure intra-operative 30^th minute and 24hr post-OR. A angle higher in high pressure. Postoperative K value lower in high pressure

between high and normal: higher MA in high pressure 24hr post-OR. A angle higher in high pressure. Postoperative K value lower in high pressure.

Conclusion: between normal and low no difference, between high and normal/low, increased trombotic activation.

M:X

N:X

O:X

P:X

Q:X

R:X

S:X

T:X

U:X

V:X

W: X

X:X

Y:X

Z:X

AA:X

Outcome measure-5: Quality of Surgical conditions

A: It was also observed that vision whereas dissection, space for dissection, and vision whereas use of suction were felt inadequate by all the surgeons with LPLC as compared with HPLC. However, the difference was not statistically significant (P>0.05). 4 patients conversion to normal pressure because of difficulty in performing safe dissection

B: X

C: visibility 2 versus 3 (p=0.000), visibility at suction 1 versus 2 (p=0.000), space for dissection 1 versus 3 (p=0.000)

D: 5 patients of low group required insufflation to 15 mmHg because of dense adhesions around the gallbladder.

E: difficulty (1-3). 1.6 versus 1.1 (p=0.111). progression (1-3) 1.4 versus 1.0 (p=0.068). 1 case converted to normal pressure due to lack of progression, not excluded

F: X

G: X

H: X

I: X

J: X

K:X

L:X

M: no difference in visualization of pelvic organs

N: 1 patient low pressure to normal pressure due to lack of exposure. Excluded from analysis.

O: 3 patients from low to standard due to poor visualization.

P: X

Q:X

R: 2/70 patients were converted to 14 mmHg to create an feasible operative field due to obesity.

S:X

T:X

U: 3 patients (10%) of low pressure to normal pressure

V:X

W: 1/70 standard pressure not successful, 4/70 low pressure not successful. (no difference). Change to 15 mmHg sign more in low pressure.

X: 4 exclusions due to conversion from low to higher pneumoperitoneum pressure (four). Successful completion of low pressure not clearly stated.

X:X

Y:X

Z:X

AA: 2/20 patients in low pressure group converted to normal pressure to complete surgery.

Outcome measure-6: Safety

A: no complication was identified in any patient on median follow up of 11 months

B: ‘no complications related to surgery’

C: no difference in complications (bleeding and gallbladder perforation)

D: ‘no intraoperative complications occurred’

E: 2 versus 1 (p=1.000)

F: no complications developed related to anesthesia or surgery. During 30 day follow up no pulmonary or surgery related complications developed

G: X

H: one postoperative complication in each group. Low pressure 1 readmission with subhepatic abscess 7 days post-OR due to stone spillage. High pressure group: minor wound infection at umbilical ort site.

I: there was no cardiac morbidity or mortality in the perioperative period

J:X

K:X

L: no difference in intra-operative or post-operative complications

M: no difference in postoperative (grade 2 or higher) or intra-operative complications

N: There were no severe complications in either

group.

O: no complications after 4 weeks. No treatment related morbidity and mortality.

P: no postoperative mortality

Q: mortality and morbidity were nil

R: There were no significant complications in either group, and duration of surgery was comparable in the two groups.

S: no difference in bile spillage. No intra-operative or postoperative complications in either group.

T: no severe complications in either group

U:X

V: no difference in bleeding or bile leek

W: no major intraoperative complications. However, gallbladder perforation in 4 low pressure and 3 normal pressure. 2 wound infection in low pressure, 1 in normal pressure

X:X

Y:X

Z:X

AA: no difference

Outcome measure-7: nausea and vomiting

A: vomiting 3 versus 1

B: X

C: X

D: X

E: 24h cumulative nausea score 2.4 versus 4..1 p=0.358 (separate time moments also no difference)

F: nausea, vomiting or both were not observed in all patients except in 1

G: X

H: X

I: X

J: X

K:X

L:X

M:X

N:X

O: x

P:X

Q:X

R:X

S:X

T:X

U:X

V:no difference

W: X

X:X

Y:X

Z:X

AA: no difference

Outcome measure-8 recovery

A: postoperative stay 27 versus 43 hours (p<0.05)

B: X

C: X

D: 1.5 days versus 2 days (p=0.015)

E: 4.5 versus 4.7 days (p=0.751)

F: X

G: X

H: X

I:X

J: no difference in hospital stay and time needed to return to normal activity.

K:X

L:X

M: no difference in hospital stay

N:X

O:X

P:X

Q:X

R: length of stay no difference.

S: no difference in length of hospital stay

T: no difference in return to oral food and discharge

U:X

V:X

W: no difference in hospitalization. QOL comparable in social and psychological domains, but sign. Different in physical domain.

X:X

Y: Length of stay (days)

1.1     versus 1.21 (p=0.589)

Z: no difference in hospital stay (1.4 versus 1.7)

AA:X

Facultative:

Study reference

Study characteristics

Patient characteristics ²

Intervention (I)

Comparison / control (C) ³

Follow-up

Outcome measures and effect size ⁴

Comments

Nasajiyan 2014

Type of study:

RCT, double blind

Setting and country:

Iran, Jundishapur University

Funding and conflicts of interest:

unknown

Inclusion criteria:

Women 18-60 years, acute cholecystitis, ASA 1-2

Exclusion criteria:

Cholangitis, history of motion sickness, malignancy, smoking, pregnancy, receiving anti-emetic agents during past 24 hours

N total at baseline:

Intervention: 25

Control:25

Important prognostic factors²:

For example

age ± SD:

I: 45.1

C: 42.5

ASA 1-2

Groups comparable at baseline? yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with Low pressure (7-9 mmHg)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with Standard pressure (14-15 mmHg)

No other entry pressure mentioned

Length of follow-up:

24 hours

Loss-to-follow-up:

unknown

Incomplete outcome data:

Unknown. Stated: ‘patients with persisted nausea for more than 20-30 minutes received ondasetron 4 mg and were excluded the study’

Outcome measures and effect size (include 95%CI and p-value if available):

Post operative nausea and vomiting (PONV). Nausea measured by VAS (0-1=no nausea, 1-4=mild, 4-7=moderate, 7-10=sever), vomiting by frequency of emetic episode per 24 hours (1-2 mild, 3-4 moderate, 5 or more severe)

Outcome 1 – Nausea (total frequency)

0-4 hours 9 versus 14 (p=0.500)

4-8 hours 4 versus 8 (p=0.160)

8-12 hours 6 versus 10 (p=0.269)

12-24 hours 3 versus 5 (p=0.351)

Outcome 2 – vomiting (total frequency)

0-4 hours 3 versus 5 (p=0.702)

4-8 hours 3 versus 4 (p=0.356)

8-12 hours 0 versus 2 (p=0.490)

12-24 hours 0 versus 0 (p=0.875)

Outcome 3 – shoulder pain (incidence, no further described)

Leaving recovery room 5 versus 12 (p=0.023)

4 hours 3 versus 9 (p=0.005)

Outcome 4 – visibility

“more prolonged duration of surgery was due to the reduction of visibility of the surgeons”. But outcome measurement is not described in methods and results, only in discussion and conclusion. Not included in analysis.

Outcome 5- Operation time (min)

121 versus 107.5 (p=0.758)

Outcome 6 – Anti-emetic medication (mg)

30.65 versus 34.80

Anesthesia

Midazolam 0.05 mg/kg

Fentanyl 2 mcg/kg, Thiopental 5 mg/kg

Cisatracurium 0.1 mg/kg

Pain control

Apotel 1 gr at recovery and repeat it after 6 hours

also, NSAIDs if needed

Position

unknown

Authors conclusion

“low pressure did not reduce PONV, but lower frequency of shouldertip pain. Low pressure was associated with reduction of visibility and more prolonged duration”

Randomization

Randomization was performed based on Color Cards (Blue & Red Cards).

Topcu 2014

Type of study:

RCT

Setting and country:

Zekai Tahir Burak Women Health Education and Research Hospital

Funding and conflicts of interest:

No funding and no conflict of interest

Inclusion criteria:

ASA 1-2, undergoing elective gynecological laparoscopic surgery under general anesthesia

Exclusion criteria:

<18, pregnancy, uncontrolled diseases such as severe hypertension, diabetes mellitus and asthma

N total at baseline:

Intervention: 54

Control 1: 45

Control 2: 51

Important prognostic factors²:

For example

age ± SD:

I: 34.57

C 1: 33.06

C2: 34.01

Groups comparable at baseline?

Yes, also on type of surgery. Not on parity and gravidity

Describe intervention (treatment/procedure/test):

Gynecological laparoscopic surgery with low pressure (8 mmg)

No other entry pressure

Describe control (treatment/procedure/test):

Gynecological laparoscopic surgery with normal pressure (12 mmg)

AND

Gynecological laparoscopic surgery with high pressure (15 mmg)

No other entry pressure

12 mmHg is used as normal pressure group for further analysis

Length of follow-up:

24 hours

Loss-to-follow-up:

none

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Pain (VAS)

6h

4.83 versus 5.51 versus 5.62 (p=0.07)

12h

2.31 versus 3.08 versus 3.57 (p<0.001)

(8 different from 12 and 15)

24h

1.07 (1.38) versus 1.33 (1.66) versus 2.41 (1.33) (p<0.001)

(8 different from 15 and 12 different from 15)

Analgesic consumption (doses)

1.09 versus 1.20 versus 1.25 (p=0.07)

Length of stay

1.03 versus 1.11 versus 1.11 (p=0.32)

Operative time (min)

42.25 versus 24.04 versus 23.50 (p<0.001) (group 1 is different from group 2 and 3)

Randomization

Consecutive adults. Patients were randomized by computer into three different intra-abdominal insufflation pressure groups.

Anesthesia

Postoperative analgesia

20 mg tenoxicam (first 6h)

100 mg paracetamol i.v. every 6 hours if needed

Position

Trendelenburg position

Authors conclusion

Reduced pain scores with low insufflation pressure compared with standard or high. But low pressure may result in longer operation times

Khan 2015

Type of study:

RCT

Setting and country:

Department of Surgery, Paikistan Air Force Hospital, Islamabad, Pakistan

Funding and conflicts of interest:

none

Inclusion criteria:

ASA 1-3, uncomplicated gallstone disease undergoing laparoscopic cholecystectomy

Exclusion criteria:

Complicated gallstone disease like gallbladder perforation, empyema and common bile duct stones

N total at baseline:

Intervention: 107

Control:107

Important prognostic factors²:

For example

age ± SD:

I:41.61

C:40.39

Groups comparable at baseline?

yes

Describe intervention (treatment/procedure/test):

Laparoscopy with pneumoperitoneum 8 mmHg (low-pressure)

No other entry pressure

Describe control (treatment/procedure/test):

Laparoscopy with pneumoperitoneum 14 mmHg Standard pressure

No other entry pressure

Length of follow-up:

surgery

Loss-to-follow-up:

none

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Outcome 1 – Operation duration

97.23 versus 93.58 (p=0.34) (min)

Outcome 2 – Exposure of the operative field

‘we noticed that there was little difference’ à no numerical value

Outcome 3 – Heartrate

After induction

81.01 versus 82.57 (NS)

After 20 minutes

78.66 versus 80.80 (p<0.05)

After 40 minutes

73.87 versus 85.50 (p<0.05)

After 60 minutes

74.76 versus 83.42 (p<0.05)

End of procedure

77.01 versus 81.60 (p<0.05)

Outcome 4 – mean blood pressure

After induction

76.00 versus 74.21 (NS)

After 20 minutes

85.77 versus 96.92 (p<0.05)

After 40 minutes

80.76 versus 98.46 (p<0.05)

After 60 minutes

78.66 versus 95.85 (p<0.05)

End of procedure

80.76 versus 95.42 (p<0.05)

Outcome 5 – Oxygen saturation

After induction

98.67 versus 98.62 (NS)

After 20 minutes

98.37 versus 97.88(p<0.05)

After 40 minutes

9824 versus 97.72 (p<0.05)

After 60 minutes

99.07 versus 97.53(p<0.05)

End of procedure

98.77 versus 97.37 (p<0.05)

Outcome 6 – end-tidal CO2

After induction

30.73 versus 31.29 (NS)

After 20 minutes

31.02 versus 39.00 (p<0.05)

After 40 minutes

31.47 versus 41.27 (p<0.05)

After 60 minutes

32.73 versus 43.10 (p<0.05)

End of procedure

33.05 versus 43.37 (p<0.05)

Muscle relaxant atracurium

Used more frequently during low-pressure in order to achieve and maintain the desired pneumoperitoneum

OR medication

Unknown

Position

unknown

Randomization

Patients were randomized into two groups of non-probability consecutive sampling using table of random numbers feature of IBM SPSS version 21.

Authors conclusion

LPP shows parameters closer to normal compared to SPP

LPP reduces potentially harmful physiological changes encountered in the SPP. But limited exposure of operative field in LPP. Safety needs to be established further. It should be reserved for patients with old age and moderate to severe cardiovascular and pulmonary diseases and co-morbid.

Reviewers note

All values are within normal limits (except HR>75, which is normal in LPP for 40 and 60 minutes)

Sattar 2015

Type of study:

RCT

Setting and country:

Surgical Unit-II, department of general surgery, Lahore

Funding and conflicts of interest:

unknown

Inclusion criteria:

>18, male & female, symptomatic gall stones assessed clinically, biochemically, imaging, planned to undergo laparoscopic cholecystectomy

Exclusion criteria:

Acute cholecystitis, cholangitis, CBD stones, gall stone pancreatitis, BMI>30, ASA III and IV

N total at baseline:

Intervention: 90

Control: 90

Important prognostic factors²:

For example

age ± SD:

I:40.41

C:38.71

Groups comparable at baseline?

yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with low pressure (<12 mmHg)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with standard pressure 12-16 mmHg

No other entry pressure mentioned

Length of follow-up:

24 hours

Loss-to-follow-up:

none

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Pain (VAS) (measured at 6,12,18,24 hours)

Only mean VAS mentioned

2.84 versus 3.46 (p=0.001)

Shouldertip pain (amount of patients)

24 hours

84 versus 67 (p=0.001)

Operative time (min)

37.4 versus 35.4 (p=0.1125)

OR medication

Non-narcotic analgesics were used 12 hourly

Anesthesia unknown

Randomisation

“patients were divided in two groups randomly using random number tables”

Position

unknown

Authors conclusion

Low pressure pneumo-peritoneum imparts significant patient advantages and we advocate its usage based on our findings however a larger scale study incorporating other variables is required to fully set this low pressure technique as a gold standard.

Zaman 2015

Type of study:

RCT, double blind

Setting and country:

MMU Medical College and Hospital, Solan

Funding and conflicts of interest:

None

Inclusion criteria:

Undergoing Laparoscopic cholecystectomy for uncomplicated cholelithiasis, 18-60 years old

Exclusion criteria:

Acute cholecystitis, pregnancy

N total at baseline:

Intervention: 25

Control: 25

Important prognostic factors²:

unknown

Describe intervention (treatment/procedure/test):

Laparoscopy with low pressure pneumoperitoneum (10 mm Hg)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopy with standard pressure pneumoperitoneum (14 mm Hg)

No other entry pressure mentioned

Length of follow-up:

24 hours

Loss-to-follow-up:

None

Incomplete outcome data:

Operative time, analgesic consumption, postoperative hospital course and complication rates are mentioned, but results are not presented.

Outcome measures and effect size (include 95%CI and p-value if available):

Outcome 1 – shouldertip pain (incidence)

2 versus 8 (p<0.05)

Outcome 2 – VAS pain

0.92 versus 5.72 (p=0.012) (mean of 8,12,24,48 hours)

OR medication

Unknown

Position

unknown

Randomization

Randomization of cases

was done according to randomization chart

Authors conclusion

Low pressure (10 mmHg) results in significant reduction in both the

intensity and frequency of postoperative shoulder tip

pain, shorter hospital stay, early recovery, and

hence better outcome.

Ali S. 2016

Type of study:

RCT

Setting and country:

Lady Reading Hospital Peshawar

Funding and conflicts of interest:

This study was originally conducted and accepted as a dissertation for the fellowship exam of the College of Physician & Surgeons of Pakistan in the subject of General Surgery

Inclusion criteria:

Elective laparoscopic cholecystectomy for cholelithiasis and normal CBD and liver on ultrasound

Exclusion criteria:

Technically difficult LC or those converted to open, history of co-morbid conditions and complaining of shoulder pain before surgery

N total at baseline:

Intervention: 80

Control:80

Important prognostic factors²:

For example

age ± SD:

I: 40.74

C:41.10

Groups comparable at baseline? yes

Describe intervention (treatment/procedure/test):

Laparoscopy with low pressure peritoneum (≤10 mmHg)

No different entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopy with normal pressure peritoneum (>10 mmHg)

No different entry pressure mentioned

Length of follow-up:

24 hours

Loss-to-follow-up:

none

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Outcome 1 – Operative time (min)

27.84 versus 28.51 (p=0.625)

Outcome 2 – shouldertip pain at 8 hours (incidence)

6 versus 19 (p=0.005)

Outcome 3 – Shouldertip pain at 8 hours (VAS)

0.28 versus 1.31 (p=0.001)

Outcome 4 – Analgesic requirements

2.24 versus 2.41 (p=0.02) (mean number of injections Ketorolac in 24 hours)

Pre-OR medication

Unknown

Medication end of surgery

Tramadol 50 mg iv

Ketorolac 30 mg iv

Randomization

A consecutive non-probability sampling technique was used. All patients were randomized into two groups.

Authors conclusion

less shoulder tip pain in low intra-abdominal pressure laparoscopic cholecystectomy as compared to standard pressure laparoscopic cholecystectomy without causing any effect on the duration of surgery.

Position

unknown

Donmez 2016

Type of study:

RCT

Setting and country:

Haseki Training and research Hospital

Funding and conflicts of interest:

No funding

No competing interests

Inclusion criteria:

Patients with symptomatic gall bladder stone, diagnosed using hepatobiliary ultrasonography.

Exclusion criteria:

Patients with DVT, history of pulmonary emboli, anticoagulant usage, malignancy, acute cholecystitis, bleeding diathesis, pregnancy

N total at baseline:

Intervention: 28

Control: 27

Important prognostic factors²:

For example

age ± SD:

I:47

C: 52

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with 10 mm Hg (low)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with 14 mm Hg (normal)

No other entry pressure mentioned

Length of follow-up:

24 hours

7 day for DVT ultrasound

Loss-to-follow-up:

Intervention: 3 (10%)

Reasons

discontinued intervention (n=1), missing data (n=2)

Control:

2 (6.7%)

Reasons

discontinued intervention (n=1), missing data (n=1)

50 analyzed

Incomplete outcome data:

7 day follow up ultrasound mentioned in methods, not in results. Conclusion states that ´they did not encounter clinical or ultrasonographicDVT or pulmonary emboli in this study population”

Outcome measures and effect size (include 95%CI and p-value if available):

Leakage from the liver bed (negative-pressure hemovac drain usage)

5/25 versus 3/25

(drains discharged on 1^st postoperative day)

Hemodynamic adverse events

No hemodynamic adverse events during pneumoperitoneum

Determined values

Hypertension: >160/90, hypotension: MAP<70, bradycardia: HR<50, tachycardia: HR>100

PT (sec)

Pre

11.94 versus 11.66 (p=0.175)

After 1 hour

12.10 versus 11.99 (p=0.505)

After 24 hours

12.43 versus 12.56 (p=0.557)

APTT (sec)

Pre

22.80 versus 22.01 (p=0.575)

After 1 hour

23.42 versus 23.32 (p=0.129)

After 24 hours

24.54 versus 25.01 (p=0.429)

TT

Pre

19.88 versus 22.38 (p=0.055)

After 1 hour

17.78 versus 17.80 (p=0.971)

After 24 hours

16.06 versus 16.12 (p=0.833)

INR (standard value)

Pre

1.0     versus 0.98 (p=0.183)

After 1 hour

1.02 versus 0.99 (p=0.058)

After 24 hours

1.04 versus 1.05 (p=0.618)

D-Dimer (mg.dl)

Pre

0.31 versus 0.31 (p=0.308)

After 1 hour

0.56 versus 0.68 (p=0.307)

After 24 hours

0.91 versus 1.51 (p<0.001)

Fibrinogen (mg/dl)

Pre

224 versus 225 (p=0.906)

After 1 hour

278 versus 282 (p=0.797)

After 24 hours

356 versus 359 (p=0.802)

Surgery time (min)

54 versus 57 (p=0.300)

Complications

No difference in surgical complication (1 versus 0 (p>0.999))

1 post-operative wound infection in low pressure group, unclear if this is counted as a surgical complication

Surgical field

“Adequate exposure of surgical field was achieved in both groups of patients.” Mentioned in results, not in methods section. Method of measurement is not described. Not included in analysis.

ASAT, ALAT, LDH mentioned, but not included for this analysis

OR medication

Propofol 2-2.5 mg/kg

Fentanyl 1 µg/kg

Rocuronium 0.6 mg/kg

No prophylactic LMWH

ASA I-III patients

Randomization

Patients were randomly assigned to one of two groups according to the pressure of pneumoperitoneum. Randomization was performed by a computer.

Position

Trendelenburg

Authors conclusion

Low and normal pneumoperitoneum have similar effects on human hemodynamics and metabolism and resulted in a significant increase in coagulation factors in both groups.

According to the increases in coagulation parameters, higher CO2 pressure has a more negative effect on coagulation cascade and fibrinolysis. All these changes were reversible, and we did not observe any complications in either group.

We suggest lower pressure because of less pronounced effects on the coagulation and fibrinolytic system.

Sharma 2016

Type of study:

RCT

Setting and country:

Department of General Surgery, Chandigarh, India

Funding and conflicts of interest:

There is no conflict of interest or financial ties to disclosure

Inclusion criteria:

>18, scheduled for elective LC

Exclusion criteria:

Conditions that affect blood coagulation, patient on anticoagulants or drugs that interfere with coagulation, pregnancy, history of jaundice or with cholelithiasis, BMI>30, patients in whom pneumoperitoneum could not be kept constant during surgery

N total at baseline:

Intervention: 25

Control:25

Important prognostic factors²:

For example

age ± SD:

I: 42.08

C:40.88

Groups comparable at baseline?

yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with 8 mmHg (low)

No different entry pressure

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with 14 mmHg (normal)

No different entry pressure

Length of follow-up:

surgery

Loss-to-follow-up:

unknown

Incomplete outcome data:

None

Outcome measures and effect size (include 95%CI and p-value if available):

Time-points

Pre-operative (after induction anesthesia, before pneumoperitoneum)

Intra-operative (just before completion surgery with pneumoperitoneum maintained)

Complications

“No intra-operative complications in both groups (not specified)”

Conversion

No conversion to open surgery among groups

Duration of surgery

55.32 versus 50.36 (p=0.124)

Coagulation profile

Pre-operative

No difference between groups in PT (p=0.77), PTI (prothrombin index) (p=0.17), APTT (p=0.90), INR (P=0.49)

End of surgery

Difference in PTI (p=0.007), no difference in PT (p=0.122), APTT (0.109) and INR ((p=0.066)

(absolute number not available)

Also femoral vein diameter, not included for this analysis

Randomization

by sealed envelope method

OR medication

Selective pre-anesthetic medication as day care patients

Single dose of antibiotic

Anesthesia was standardized using the same sedatives, narcotics and muscle relaxants for all patients included in this study

Position

Unknown

Authors conclusion

Changes of coagulation parameters (and femoral vein hemodynamic) were less pronounced at low pressure

Bhattacharjee 2016

Type of study:

RCT

Setting and country:

Tertiary care referral hospital

Funding and conflicts of interest:

none

Inclusion criteria:

Elective laparoscopic cholecystectomy for gallstone disease, age 18-60

Exclusion criteria:

BMI>30, ASA ≥III, history of complicated gallstone diseases like acute cholecystitis, cholangitis, pancreatitis, ERCP and stenting, significant co-morbidities like coronary artery disease, asthma, COPD, previous malignancy or history of multiple abdominal surgery, known shoulder disease, chronic analgesic use, patient requiring concomitant procedures

N total at baseline:

Intervention: 40

Control:40

Important prognostic factors²:

For example

age ± SD:

I:35.32

C:37.92

BMI:

I: 25.197

C:24.66

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Elective laparoscopic cholecystectomy low pressure (9-10 mmHg)

No different entry pressure

Describe control (treatment/procedure/test):

Elective laparoscopic cholecystectomy standard pressure (14 mmHg)

No different entry pressure

Length of follow-up:

7 days

Loss-to-follow-up:

none

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Postoperative shoulderpain (incidence)

9 versus 23 (p<0.001)

Median pain (VAS)

8h and 24h sign. more pain in standard pressure group (p=0.009 and p=0.005), other moment no difference (4h, 7 days)

Rescue analgesia (amount of patients)

4h

0 versus 0

8h

3 versus 5 (p=0.71)

24h

0 versus 5 (p=0.05)

7 days

0 versus 0

Abdominal pain (VAS)

Median pain (VAS)

4h sign. more pain in standard pressure group (p=0.001) (other moments no difference (8,24h, 7 days)

Rescue analgesia (amount of patients)

4h

4 versus 11 (p=0.08)

8h

1 versus 6 (p=0.11)

24h

0 versus 0

7 days

0 versus 0

Intra-operative HR and BP

No difference in HR (overall, p=0.473)

Intra-operative 74.5-80.1 versus 76.8-84.7

No difference in systolic BP (overall, p=0.709)

Intra-operative 112.4-123.1 versus 100.7-121.7

No difference in diastolic BP (overall, p=0.91)

Intra-operative 69.4-88.7 versus 69.4 versus 74.9 (p=0.499)

Visibility (surgeon satisfaction on exposure and instrument manoeuvrability)

Satisfaction 1-5 (1= very poor, 5=good)

- Entry

4.63 versus 4.72 (p=0.46)

-Exposure of fundus and body of gallbladder

4.73 versus 4.83 (p=0.32)

-Exposure of Calot’s triangle

4.32 versus 4.4 (p=0.62)

- dissection of Calot’s triangle

4.2 versus 4.2 (p=0.99)

-Exposure during separation of gall bladder

4.5 versus 4.4 (p=0.48)

-Dissection of the gall bladder from the liver bed

4.5 versus 4.45 (p=0.73)

Overall:

26.8 versus 27 (p=0.84)

(max 30)

Intra-operative and postoperative details

Gall bladder perforation

12 versus 14 (p=0.63)

Spillage of stone

4 versus 3 (p=0.99)

Complications

No mortality, bile duct injury or conversion in either group

No conversion from low pressure to standard pressure

Operative time

38.5 versus 38 min (p=0.43)

Randomization

Consecutive patients, computer-generated random numbers, blocks of 8. Sequentially numbered sealed opaque envelopes to ensure concealment of allocation

OR medication

200 mg ciprofloxacin at time of induction and 6h after surgery

Anesthesia

Propofol

Fentanyl

Non-depolarising muscle relaxants, atracurium, vecuronium

Analgesia

Fentanyl (as and when considered necessary by the attending anaesthesiologist)

Infiltration 5ml bupivacaine around umbilicus

Post-OR

Diclofenac sodium iv 75 mg 6 hourly in first 12 h.

After that oral PCM 325 + ibuprofen 400 mg 8 hourly

Rescue analgesia: injection fentanyl citrate 30 mcg, on demand

Discharge: oral (PCM 325 mg + ibuprofen 400 mg) and rescue: tramadol hydrochloride 50 mg

Position

Unknown

Authors conclusion

the incidence and severity of shoulder pain following LC performed at low-pressure pneumoperitoneum are significantly less compared to that in standard-pressure pneumoperitoneum. The safety, efficacy and surgeons’ satisfaction appear to be comparable in both the groups.

Matsuzaki 2017

Type of study:

RCT

Setting and country:

CHU Clermont-Ferrand

Funding and conflicts of interest:

No competing interest

Funding by Karl Storz Endoscopy & GmbH and the Fondation de l’ Avernir

Inclusion criteria:

All patients who underwent laparoscopic sub-total hysterectomy with promontofixation for uterine prolapse

45-75 year, ASA 1-2

Exclusion criteria:

History of pelvic surgery for endometriosis and/or infection, pathological peritoneal tissue such as endometriosis, peritoneal adhesions, BMI>30, height<150,

After randomization

-Adhesions detected just after insertion of four trocars

-a different surgical technique is needed because the sacral promontory is not clearly identified

-IPP is changed during the surgery, conversion to laparotomy

N total at baseline:

11 patients did not receive allocated intervention, therefore not analysed (due to intraperitoneal adhesion or sacral promontory not clearly identified)

Intervention: 41

Control:41

Important prognostic factors²:

For example

age ± SD:

I: 61.0

C:63.8

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Laparoscopic sub-total hysterectomy with promontofixation with low pressure (8 mmHg)

(insertion pressure 15 mmHg) (all 4 trocars)

With WH: 20

Without WH: 21

WH: Warmed, humidified CO2

Describe control (treatment/procedure/test):

Laparoscopic sub-total hysterectomy with promontofixation with standard pressure (12 mmHg)

(insertion pressure 15 mmHg) (all 4 trocars)

With WH: 20

Without WH: 21

WH: Warmed, humidified CO2

Length of follow-up:

30 days

Loss-to-follow-up:

none

Incomplete outcome data:

Post OR pain, not every patient every moment, but well documented

Outcome measures and effect size (include 95%CI and p-value if available):

Surgical conditions (visibility, difficulty, working space, pain experienced)

Worse for low pressure for difficulty and working space. Not for visibility

Operative technical difficulty (0=no difficulty, 100 = worst level)

27 versus 17 (p=0.007)

Working space (0=worst level of space, 100=optimal)

(for dissection) 74 versus 83 (p=0.004)

(for suturing) 73 versus 85 (p<0,001)

Visibility (0= worst visibility, 100 = perfect)

84 versus 85 (p=0.61)

Pain (0=no pain, 100=worst pain)

15 versus 10 (p=0.12)

Quality of post-OR recovery (QoR-40)

Global score: 1.4 (p=0.006), better in low pressure)

Subcategories

• emotional state: no difference
• physical comfort: no difference
• Physiological support: better in low pressure (0.07, p=0.04)
• Physical independence: no difference
• Pain: better in low pressure at 24 hours (2.3, p<0.001) and at 48 hours (1.6, p=0.008). no difference at 30 days

Better recovery in the pain dimension in low pressure group (p=0.008)

Operative time (min)

168.9 versus 171.6 (p=0.60)

PACU Length of stay (Min)

98.7 versus 109.4 (p=0.19)

Morphine requirement in PACU

Amount of patients

18 versus 24 (p=0.20)

Median morphine (mg)

0 versus 2 (p=0.41)

Morphine requirement in ward

Amount of patients

1 versus 4 (p=0.36)

Complications

Stomach perforation

1 versus 0 (due to veress needle)

No postoperative complications

VAS Pain scores

(<30=no or mild pain, >30=clinically relevant moderate to severe pain)

No shoulder pain

No interaction VAS pain and pressure for >30 in PACU

Odds ratio VAS>30

0.18 (95% CI: 0.06, 0.52) at 12 hours 0.06 (95% CI: 0.01, 0.26) at 24 hours

(12 mmHg worse)

Amount of patients with VAS>30 in ward

0h

28/41 versus 31/41

4h

14/41 versus 18/40

8h

8/41 versus 13/41

12h

4/41 versus 11/41

16h

4/38 versus 12/39

20h

2/33 versus 8/34

24h

0/41 versus 10/41

48h

1/28 versus 8/29

OR medication

1 mg/kg hydroxyzine hydrochloride suspension 1 hour pre-OR oral

0.2 mcg/kg sufentanil

3 to 5 mg/kg IV propofol. Two mg/ kg IV cisatracurium were used to facilitate tracheal intubation.

Desflurane and target-controlled infusion of sufentanil

Neuromuscular blockade was maintained using cisatracurium.(unknown moderate or deep)

All incisions were made after ropivacaine infiltration

Prevention PONV

8 mg IV dexamethasone at the beginning of intervention

1 mg IV droperidol 1 and 4 mg IV ondansetron at the end of intervention

Prevention Post-OR pain

30 minutes before the end of intervention 1 g IV paracetamol and 50 mg IV ketoprofene.

And ropivacaine under right hemidiaphragm

Post-OR

PACU

When the pain score was >30 of 100, postoperative pain was treated with an IV bolus of 2 to 3 mg morphine, and then 1 to 2 mg IV every 10 minutes to achieve a pain score ≤30 of 100. Intravenous patient-controlled analgesia (IV-PCA) was prepared using morphine (1 mg/mL) and droperidol (0.05 mg/mL).

Ward

All patients received 1 g paracetamol and 50 mg of ketoprofene IV every 6 hours until 24 hours postoperatively. Then, pain was managed using oral paracetamol and ketoprofene.

Randomisation

2x2 factorial, four-parallel-group, single blinded (patients), superiority randomized trial

1:1:1:1 ratio by remote 24-hour-a-day computer-generated randomization system using an algorithm with BMI (<25 versus >25), height (<160 versus >160), age (<65 versus >65) as minimization covariates. IPP and type of CO2 gas as factors in factorial design

Patients were blinded for the allocated treatment arm until the end of the study. The nurse anesthetists in the postanesthesia care unit (PACU) and the ward nurses, who evaluated postoperative pain using a visual analogue scale (VAS), were also blinded. The database was submitted for analysis to independent statisticians who were blinded and were neither involved in the trial management nor employed by the trial sponsor.

Position

Trendelenburg

Author’s conclusion

LPP independently decreased the likelihood of a high VAS Pain score (>30) after surgery

Mohammadzade 2018

Type of study:

RCT

Setting and country:

Velayat Hospital, Qazvin, Iran

Funding and conflicts of interest:

No conflict of interest

Inclusion criteria:

20-70 year

Exclusion criteria:

Rupture of gallbladder, empyema, common bile duct stones, undergoing extensive upper abdominal surgery, pregnant females, BMI>30 and <19, fatty liver grade 3 and 4, elevated liver enzymes

N total at baseline:

Intervention: 30

Control:30

Important prognostic factors²:

For example

age ± SD:

I: 39

C:36.4

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy 7-10 mmHg (low)

No difference for introduction is mentioned

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy 12-14 mmHg (normal)

No difference for introduction is mentioned

Length of follow-up:

24 hours

Loss-to-follow-up:

unknown

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Abdominal pain (verbal rating scale VRS) (range 0-4) (amount of people that scored all rank 1-4)

1h

P=0.18

3h

P=0.001

6h

P=0.04

12h

P=0.001

24h

P=0.001

(all in favour of low pressure)

Shoulder-tip pain (VRS 0-4, amount of people that scored all rank 1-4)

1h

P=0.03

3h

P=0.03

6h

P=0.03

12h

P=0.001

24h

P=0.02

(all in favour of low pressure)

PONV (verbal rating scale VRS) (range 0-4, amount of people that scored all rank 1-4)

1h

P=0.1

3h

P=0.03

6h

P=0.4

12h

P=0.001 (in favour of low pressure)

24h

P=0.23

Hemodynamics, repeated measures, more timepoints (admission surgery – 6 hour after surgery)

Mean systolic blood pressure

P=0.01 (low pressure group lower)

From figure: 110-120 versus 118-127 (range)

Mean diastolic blood pressure

P=0.08

From figure: 67.50-77.50 versus. 72-75 (range)

Heart rate

P=0.001 (low pressure group lower)

From figure: 79-85 versus 81-88 (range)

Liver enzymes

Not included in this analysis

Randomization

Double-blind randomized clinical trial

Randomly categorized into 2 groups of 30

OR medication

The standard four-port method, the same surgical method, and general anesthesia were used in the two groups. The same anesthesia protocol was used in both groups.

Position

Unknown

Author’s conclusion

Low-pressure CO2 decreases hemodynamic complications and also the levels of abdominal and shoulder-tip pains

Nematihonar, 2018

Type of study:

RCT

Setting and country: Iran

Funding and conflicts of interest:

No conflict of interest

Inclusion criteria:

ASA I-II, 20-85 year, elective laparoscopic cholecystectomy

Exclusion criteria:

Pregnancy, cholangitis, carcinomas, history of previous laparotomy, addiction or mental illnesses, conversion to open cholecystectomy, occurrence of intraoperative bleeding >500 mL, operation time >2h

N total at baseline:

Intervention: 101?

Control:101?

Unclear. Materials & methods states 101 subjects each group needed. Results section does not state amount of subjects. Table 1 and 2 state n=101, unclear if this is per group or total

Important prognostic factors²:

For example

age ± SD:

I:44.5

C:45.3

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with low pressure (6-8 mmHg)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with normal pressure 12-14 mmHg)

No other entry pressure mentioned

Length of follow-up:

Surgery

Loss-to-follow-up:

unknown

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Operation time (min)

32.5 versus 31.6 (p=0.25)

Blood gas beginning of surgery, before CO2 insufflation

ETCO2 (End-Tidal CO2)

29.5 versus 30.4 (p=0.55)

PaCO2

27.8 versus 28.2 (p=0.21)

MAP

95.3 versus 95.8 (p=0.55)

5 minutes after insufflation

ETCO2 (End-Tidal CO2)

37.3 versus 37.8 (p=0.38)

MAP

76.2 versus 70.5 (p=0.001)

10 minutes after insufflation

ETCO2 (End-Tidal CO2)

36.8 versus 37.1 (p=0.48)

MAP

77.4 versus 72.7 (p=0.006)

Blood gas end of surgery, before CO2 desufflation

ETCO2 (End-Tidal CO2)

31.5 versus 34.6 (p=0.001)

PaCO2

31.4 versus 34.8 (p=0.001)

MAP

79.4 versus 72.5 (p=0.001)

Randomization

Randomly divided into two groups

OR medication

Premedication

Midazolam 0.02 mg/kg, fentanyl 2 μg/kg IV

Induction of anesthesia

propofol 1-2 mg/kg, atracurium 0.5 mg/kg IV.

Anesthesia was maintained

by propofol 100-150 μg/kg/h and remifent­anil 0.1 μg/kg/h, (keep the BIS score between 40 and 60)

Ringer’s solution infusion as hy­drating agent compatible to intraoperative fluid therapy management.

Position

Unknown

Author’s conclusion

Low pressure can be a preventive measure against partial pressure increase of CO2 in arterial blood and an appropriate way to preserve MAP

Neogi 2019

Type of study:

RCT

Setting and country:

Department of surgery, India

Funding and conflicts of interest:

Unknown

Inclusion criteria:

All patients posted for elective laparoscopic cholecystectomy

Exclusion criteria:

Deranged liver function, history of prior major abdominal surgery, ASA>II, chronic drug abuse affecting liver, evidence of bile duct stone, difficult gall bladder assessed clinically and radiologically, ERCP within 10 days before the laparoscopic procedure

N total at baseline:

Intervention: 40

Control: 40

(8 from low pressure converted to normal pressure, no intention to treat)

Analysis: 32 versus 48

Important prognostic factors²:

For example

age ± SD:

I: 39.68

C:37.79

Groups comparable at baseline?

yes

Describe intervention (treatment/procedure/test):

Low pressure laparoscopic pneumoperitoneum (7 mmHg)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Standard pressure laparoscopic pneumoperitoneum (14 mmHg)

No other entry pressure mentioned

Length of follow-up:

Day 7 post surgery

Loss-to-follow-up: non lost to follow up but

Conversion

8 patients from low pressure converted to normal pressure due to difficulty in dissection.

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Analysis per protocol 32 versus 48

Also liver enzymes

(24h postpartum sometimes different, after 7 days no difference)

Operation time

56.4 versus 54 min

Adverse event

Minor leak (not included as complication in analysis)

1 versus 0

Serious adverse events (bile duct injury, bowel injury, excessive bleeding. Life threatening, requiring a longer hospital stay or significant or persistent disability

0 versus 0

Conversion

8 patients from low pressure converted to normal pressure due to difficulty in dissection. These patients were analysed via per-protocol, so in the other group.

Surgeons comfort (1-10_

Ease of port insertion

7.39 versus 9.75 (p<0.05)

Visibility

7.45 versus 9.42 (p<0.05)

Manipulation of port

6.42 versus 9.36 (p<0.05)

Ease of dissection

5.9 versus 9.57 (p<0.05)

Resume to normal activity

All patients in both groups resumed their normal activity by seventh day follow-up. Not included in analysis, as no clear comparison was made.

Randomization

Double blinded, parallel group, randomized controlled, trial

Randomly into 2 groups by using computer generated block randomization technique. Operating surgeon was provided with sealed envelope after induction of anesthesia. Patients and nursing staffs involved in postoperative care were blinded about the group till the collection of the final samples on day 7

OR medication

All patients similar anesthetic, intraoperative and postoperative protocol.

night before surgery

0.5 mg alprazolam

Induction

Propofol and atracurium

Analgesic

Remifentanil

Anesthesia maintained

Isoflurane, NO, O2

Reversal

Glycopyrrolate, neostigmine

Postoperative analgesia

Fentanyl per the patient need

Position

Anti-trendelenburg

Author’s conclusion

LPP is a safe procedure, especially in the hands of an experienced surgeon with clinically insignificant systemic effects. The comfort level of surgeon is certainly better in normal pressure compared with low pressure. Further studies are needed to determine the comfort and stress level of surgeons in long-duration surgery. If the same level of comfort and safety can be established in advanced laparoscopic surgeries, LPP can be recommended for patients with deranged hepatic and cardiovascular functions. We advise the surgeons to start with low pressure and escalate the pressure as per need.

Pulle 2019

Type of study:

RCT

Setting and country:

Unit of a tertiary centre in New Delhi

Funding and conflicts of interest:

none

Inclusion criteria:

18-60 years, admitted for laparoscopic cholecystectomy

Exclusion criteria:

Mirizzi syndrome and/or extensive upper abdominal incisions, >60 years, >ASA II

N total at baseline:

Intervention: 94 (100 included but 6 excluded from analysis due to conversion to normal pressure due to intraoperative difficulty)

Control: 100

Important prognostic factors²:

For example

age ± SD:

I:39.27

C:40.63

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with low pressure (8-10 mmHg)

No other entry pressure mentioned

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with standard pressure (13-15 mmHg)

No other entry pressure mentioned

Length of follow-up:

48 hours

Loss-to-follow-up:

Conversion

6 patients from low pressure converted to normal pressure due to difficulty in dissection. These patients were excluded from analysis

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Conversion

6 patients from low pressure converted to normal pressure intraoperative difficulty. These patients were excluded from analysis

Operation time (min)

39.27 versus 40.63 (p=0.50)

Difficulty in surgery due to low space (incidence)

7 (7.4%) versus 0 (p=0.005). they continued in low pressure

Shoulder-tip pain (VAS)

4h

3.06 versus 2.74 (p=0.452)

24h

4.74 versus 4.46 (p=0.308)

48h

1.50 versus 1.94 (p=0.175)

Shoulder-tip pain (incidence)

Total

19 versus 24 (p=0.526)

4h

17 versus 19 (p=0.870)

24h

19 versus 24 (p=0.526)

48h

14 versus 17 (p=0.689)

Additional analgesic dose (incidence)

13 versus 20 (p=0.253)

Randomization

Single-blind. Randomized based on computer-generated random allocations

Conversion

Decision to convert to normal pressure as taken within 15 minutes from trocar insertion

Pain medication

All patients were given injectable analgesics (Nonsteroidal anti-inflammatory drug) at an interval of 8h. An additional dosage of analgesics was given for patient requirement.

Position

Unknown

Author’s conclusion

LPP does not lower incidence and severity of postoperative shouldertip pain. LPP showed intra-operative difficulty because of inadequate exposure in the low pressure group. Use of LPP can jeopardise the patients safety and surgeons comfort

Radosa 2019

Type of study:

RCT

Setting and country:

Department of Gynaecology and Obstetrics, Saarland University Hospital, Homburg, Germany

Funding and conflicts of interest:

Funded by a research grant from the Saarland institutional review board

JCR has received travel grants from Medac GmbH, Gedeon Richter and Celgene outside the submitted work in the past. EFS is receiving grants from University of Saarland,Storz, Erbe; personal fees and others from Roche, Pfizer,Celgene, Amgen and Astra Zeneca; other fees from Johnson& Johnson, Novartis, Tesaro, Medac GmbH, MSD, Vifor,Gedeon Richter, Takeda, and AGE, outside the submitted work. LS has received travel grants from Medac GmbHoutside the submitted work in the past. The other authors declare no conflict of interest. Completed disclosure of interests forms are available to view online as supporting information.

Inclusion criteria:

Performance of hysterectomy due to benign uterine pathology, availability of complete information of outcome measures

Exclusion criteria:

Performance of additional surgical procedures or abandonment of the intended surgical procedure, discovery of malignant uterine neoplasia on final pathological examination, unavailability of 48 hour post-operative pain intensity scores and/or postoperative pCO2 measurement

N total at baseline:

Intervention: 102 (2 excluded due additional intervention)

Control:105

(4 excluded due additional intervention)

Important prognostic factors²:

For example

age ± SD:

I: 51 (median)

C:49 (median)

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Hysterectomy with low pressure (8 mmHg)

Same entry pressure

Describe control (treatment/procedure/test):

Hysterectomy with standard pressure (15 mmHg)

Same entry pressure

Length of follow-up:

30 days

Loss-to-follow-up:

Intervention: 9

Reasons

Incomplete postoperative pCO2 pressure (n=1)

Incomplete pain questionnaire (n=8)

Control:

14

Reasons

Incomplete postoperative pCO2 pressure (n=2)

Incomplete pain questionnaire (n=12)

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Analysis based on n=91 versus n=87

Abdominal pain (NRS, median))

3h

1 versus 4 (p≤0.01)

24h

1 versus 4 (p≤0.01)

48h

1 versus 2 (p≤0.01)

Shoulder pain (NRS, median))

3h

0 versus 1 (p≤0.01)

24h

0 versus 1 (p≤0.01)

48h

0 versus 0 (p≤0.01)

Piritramide requirement (mg)

1 versus 5 (p≤0.01)

Nausea (presence, incidence)

3h

32 versus 24 (p=0.18)

24h

6 versus 17 (p≤0.01)

48h

12 versus 6 (p=0.08)

Vomiting (presence, incidence)

3h

0 versus 9 (p≤0.01)

24h

0 versus 5 (p≤0.01)

48h

2 versus 3 (p=0.1)

Operation time (min)

95 versus 120 (p=0.1)

Intra-operative complications

Bowel injury

0 versus 0

Bladder injury

0 versus 2 (p=0.15)

Ureter injury

0 versus 0

Conversion to laparotomy

0 versus 0

Conversion

No case of low pressure was converted to standard pressure due to increase of CO2 pressure (reason of surgeon comfort not mentioned, so not included in analysis of surgeon comfort)

Surgical complications postoperative (minor = I-II Clavien-Dindo, major – III-IV Clavien-Dindo)

Minor

1 versus 2 (p=0.86)

Major

0 versus 1 (p= unknown)

Arterial pCO2 (mmHg, median)

Pre-operative

37.1 versus 36.7 (p=0.7)

30 minutes intraoperative

40.1 versus 41 (p<0.01)

End of surgery

40.9 versus 46.9(p<0.01)

1h postoperative

40.9 versus 45.2 (p<0.01)

3h postoperative

39.1 versus 42.2 (p<0.01)

6h postoperative

37.8 versus 40.3 (p<0.01)

Post-operative hospitalisation (days, median)

3 (2-6) versus 3 (1-10) (p<0.01)

Also bowel movement, bloating described. Not included for this analysis

Randomization

Computer generated random number lists. Sealed envelopes with randomisation numbers were prepared by a study nurse uninvolved in the trial. Envelope was added randomly to each patients file on the day before hysterectomy and opened by the surgeon in the operation room.

OR medication

Pre-OR

Cefuroxime

LMWH

Anesthesia

Fentanyl 0.01 µg/kg

Propofol 1% 1-2 mg/kg

Atracurium 0.3-0.5 mg/kg

Maintenance

Desflurane 0.5-0.7 MAC

Remifentanil 0.2-0.5 µg/kg

Prophylaxis against PONV

Dexamethasone 4 mg after induction of anesthesia

Ondansetron 4 mg, 20 minutes before end of surgery

Post-OR pain medication

Metamizole 1g/2ml diluted in 100 ml 0.9% sodium chloride every 6h

7.5 mg piritramide every 6 hours on patient request

Position

Trendelenburg

Author’s conclusion

LPP reduced postoperative abdominal and shoulder pain, vegetative alterations, pain medication requirements, arterial pC2 and hospitalisation with no difference in complications.

Kundu 2017

Type of study:

Single- blindedRCT, 6 arms

Setting and country:

Department of Gynecology, Hannover Medical School, Germany

Funding and conflicts of interest:

We have no possible conflict of interest to mention. We certify that we have no affiliation with or financial involvement in any organization or entity with a direct financial interest in the subject matter or materials discussed in the manuscript (e.g., employment, consultancies, stock ownership, honoraria). This article does not contain any studies with animals performed by any of the authors. No animals were involved in this study.

This study was financed by own funds of our department

Inclusion criteria:

Female older than 16 years, necessity of gynecological laparoscopy

Exclusion criteria:

Intraoperative conversion to laparotomy, serious postoperative complications, which had an influence on sensation of pain

N total at baseline:

Intervention: 68, 34, 67, 56, 62, 73

Important prognostic factors²:

For example

age ± SD:

I: 42.8 versus 41.6 versus 45.5 versus 45.1 versus 41.6 versus 43.1

Groups comparable at baseline?

yes

Describe intervention (treatment/procedure/test):

Laparoscopic surgery. The initial pressure was changed after insertion of all trocar, approximately 3 minutes after beginning of the surgery

Groups (initial pressure/intra-operative pressure)

Group 1: 15/10 mmHg

Group 2: 10/10 mmHg

Group 3: 15/12 mmHg

Group 4: 12/12 mmHg

Group 5: 15/8 mmHg

Group 6: 15/15 mmHg

Describe control (treatment/procedure/test):

Length of follow-up:

1 day

Loss-to-follow-up:

ITTP:

The reasons for dropout were conversion to laparotomy (n = 27), no laparoscopy (n = 24), no surgery (n = 24), double inclusion into our study (n = 10) and postoperative complications with influence on the pain (n = 9).

PPP

intraoperative deviation from the randomized CO2-pressure (n = 45), missing documentation of the uses of CO2-pressure (n = 26) and noncompliance of the surgeon (n = 19).

Pain postoperative PPP (n = 360), we analysed the patient`s pain in the morning of the first postoperative day (n = 326, 90.6%); in 14 cases we had to use the last documented pain at the day of surgery (3.9%) and in 20 cases we averaged the neighboured pain values of the surgery day and the day after surgery (5.6%) due to missing entries for the patient`s pain in the morning of the first postoperative day.

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

ITTT (n=450) and PPP (n=360)

Pain (VAS, 1^st postoperative day) (PPP)

3.00 versus 2.93 versus 2.95 versus 2.52 versus 2.96 versus 3.26 (p=0.479)

Group 4 versus group 6(P=0.036)

Hospital stay (days)

2.9 versus 2.9 versus 2.9 versus 3.3 versus 2.4 versus 3.3 (p=0.003)

Analgesia use (doses)

Non-opioid inpatient

1.5 versus 1.4 versus 1.3 versus 1.3 versus 1.1 versus 1.8 (p=0.023)

Opioid inpatient

0.0     versus 0.0 versus 1.6 versus 1.6 versus 0.3 versus 1.4 (p=0.765)

Duration of surgery

Significant relation between pain and extent and duration of surgery. More pain with hysterectomy than with surgery<60 min (p=0.019)

Anesthesia

General anesthesia

Analgesia

Paracetamol, ibuprofen, diclofenac, metamizole if needed

Also routine analgesia

Position

Trendelenburg

Authors conclusion

positive, but probably poorly relevant, effect of a lower intraoperative CO2 pressure on the postoperative pain the first day after surgery. In particular, the clinical outcome with the use of a pressure of 12 mmHg compared to 15 mmHg seems to be better. The additional benefit of an even lower pressure of 10 or 8 mmHg cannot be reliably assessed, while we found a tendency of intraoperative increasing the CO2 pressure in the low pressure groups as a sign of poor visibility conditions. Apart from the importance of the CO2 pressure we also found other factors to play an important role in the postoperative sensation of pain like patients’ age, amount of prior operations and duration of the surgery. These factors as well as the use of low intraoperative CO2 pressure need further investigations in order to clarify the importance in the clinical setting.

Goel 2019

Type of study:

RCT

Setting and country:

Santosh Medical College and Hospitals, Ghaziabad, Uttar Pradesh, India

Funding and conflicts of interest:

None

Inclusion criteria:

Symptomatic cholelithiasis 18-65 years

Exclusion criteria:

Severe cardiorespiratory comorbidities, renal failure, hepatic failure, morbid obesity, previous upper abdominal surgery, acute cholecystitis, malignancy and bleeding disorders

N total at baseline:

Intervention: 30

Control:30

Important prognostic factors²:

Age

I: 36.2

C: 35.5

Groups comparable at baseline?

Yes

Describe intervention (treatment/procedure/test):

Laparoscopic cholecystectomy with low pressure (7-10mmHg)

Trocars inserted at 12 mmHg

Describe control (treatment/procedure/test):

Laparoscopic cholecystectomy with normal pressure (12-14mmHg)

Trocars inserted at 12 mmHg

Length of follow-up: 48 hours

Loss-to-follow-up:

Unknown

Incomplete outcome data:

none

Outcome measures and effect size (include 95%CI and p-value if available):

Conversion to standard pressure due to operative difficulty

2 versus 0 (p=0.84)

Complication (like intra-operative bleeding or bile duct injury)

0 versus 0

Duration of surgery

62.6 versus 60.45 (p=0.78)

Heart rate

Before insufflation

85.3 versus 86.65 (p=0.77)

At insufflation

88.73 versus 89.43 (p=0.85)

During surgery (at 15 min)

76.60 versus. 89.53 (p=0.01)

During surgery (at 30 min)

79.37 versus 98.80 (p=0.012)

At exsufflation

78.20 versus 96.10 (p=0.005)

After exsufflation (15 min)

77.93 versus 93.73 (p=0.015)

Mean systolic blood pressure

Before insufflation

127.54 versus 128.65 (p=0.54)

At insufflation

130.56 versus 132.73 (p=0.67)

During surgery (at 15 min)

119.53 versus 141.00 (p=0.002)

During surgery (at 30 min)

121.07 versus 142.27 (p<0.001)

At exsufflation

119.87 versus 147.73 (p<0.001)

After exsufflation (15 min)

127.13 versus 142.93 (p=0.12)

Mean Diastolic blood pressure

Before insufflation

80.96 versus 82.59 (p=0.82)

At insufflation

86.78 versus 87.77 (p=0/79)

During surgery (at 15 min)

76.10 versus 90.37 (p<0.001)

During surgery (at 30 min)

80.87 versus 90.87 (p=0.017)

At exsufflation

78.10 versus 92.17 (p<0.001)

After exsufflation (15 min)

83.43 versus 90.10 (p=0.021)

Mean EtCO2

Before insufflation

29.12 versus 28.45 (p=0.89)

At insufflation

30.33 versus 33.67 (p=0.031)

During surgery (at 15 min)

31.00 versus 34.13 (p=0.045)

During surgery (at 30 min)

30.57 versus 34.77 (p=0.033)

At exsufflation

30.20 versus 35.37 (p=0.002)

After exsufflation (15 min)

30.97 versus 33.87 (p=0.011)

Shoulder pain (VAS)

12 hours

0.45 versus 2.12 (p=0.002)

24 hours

2.67 versus 4.01 (p<0.001)

48 hours

2.14 versus 2.65 (p=0.65)

Randomization

Patients for each group were selected using a chit method

Anesthesia

General anesthesia

Postoperative analgesia

Injection sodium diclofenac 75 mg intramuscularly on demand

Position

Unknown

Author’s conclusion

LC under low pressure causes minimal cardiorespiratory changes and less post-operative shoulder tip pain. LC under low pressure may be suitable for the elderly and patients with mild cardiorespiratory comorbidities.

Certainty assessment

Impact

Certainty

Importantie

Aantal studies

Studieopzet

Risk of bias

Inconsistentie

Indirect bewijs

Onnauwkeurigheid

Andere factoren

Hemodynamische kenmerken

3

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^b,c

niet gevonden

Er wordt geen klinisch relevant verschil gezien tussen de groepen bij 1 studie. Bij 2 andere studies worden er geen vergelijking tussen de groepen gedaan, maar wel binnen de groep op bepaalde tijdspunten. In beide groepen zijn geen klinisch relevante verschillen

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Kwaliteit van toegang

1

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^d

niet gevonden

Betere kwaliteit van toegang bij hoge druk (verschil 23 punten op schaal 1-100)

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Pijn

1

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^d

niet gevonden

Geen verschil

⨁◯◯◯
ZEER LAAG

BELANGRIJK

Misselijkheid

1

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^d

niet gevonden

Geen verschil

⨁◯◯◯
ZEER LAAG

BELANGRIJK

Certainty assessment

Aantal patiënten

Effect

Certainty

Importantie

Aantal studies

Studieopzet

Risk of bias

Inconsistentie

Indirect bewijs

Onnauwkeurigheid

Andere factoren

Low pressure

Normal pressure

Relatief
(95% CI)

Absoluut
(95% CI)

Algemene pijn - VAS 1 dag postoperatief

10

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

ernstig ^b

niet gevonden

379

367

-

MD 0.62 lager
(0.88 lager tot 0.36 lager)

⨁⨁◯◯
LAAG

CRUCIAAL

Algemene pijn - VAS 2 dagen postoperatief

2

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^b,c

niet gevonden

84

84

-

MD 1.1 lager
(1.37 lager tot 0.83 lager)

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Algemene pijn - VAS 3 dagen postoperatief

3

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^b,c

niet gevonden

104

104

-

MD 0.99 lager
(1.2 lager tot 0.78 lager)

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Algemene pijn

5

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^d

ernstig ^c

niet gevonden

De resultaten zijn wisselend. 2 studies beschrijven een gemiddelde VAS score over de gehele opname. De studies tonen een significant verschil, echter maar bij 1 studie is dit verschil klinisch relevant. 1 studie beschrijft een significant kleinere kans op pijn bij lage druk. 1 studie ziet een significant lagere mediane pijnscore op alle tijdsmomenten. 1 studie vergelijkt meerdere drukken en ziet geen verschil tussen lage en standaard druk.

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Schouderpijn - VAS 1 dag postoperatief

6

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

ernstig ^b

niet gevonden

224

232

-

MD 0.51 lager
(1.11 lager tot 0.09 hoger)

⨁⨁◯◯
LAAG

CRUCIAAL

Schouderpijn - VAS 3 dagen postoperatief

3

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

ernstig ^c

niet gevonden

60

60

-

MD 1.59 lager
(2.15 lager tot 1.04 lager)

⨁⨁◯◯
LAAG

CRUCIAAL

Schouderpijn

15

gerandomiseerde trials

ernstig ^a

ernstig ^e

ernstig ^d

ernstig ^c

niet gevonden

De incidentie van pijn is waarschijnlijk hoger bij een standaard druk (10/13 studies). 2 studies beschrijven de mediane pijn, waarbij 1 studie op alle postoperatieve momenten lagere pijn ziet (3,24 en 48h) en 1 studie alleen bij 8 en 24h, bij 4h en 7 dagen niet.

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Abdominale pijn

3

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^d

ernstig ^c

niet gevonden

De resultaten ten aanzien van abdominale pijn zijn erg wisselend tussen minder pijn bij lage druk of geen verschil

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Pijnmedicatie

20

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^f,g

niet ernstig

niet gevonden

5 studies zien minder analgetica gebruik bij lage druk, 11 studies zien geen verschil. 2 studies tonen binnen de studie verschillende uitkomsten op verschillende momenten/soorten medicatie.

⨁⨁◯◯
LAAG

CRUCIAAL

Cardiale functie

14

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^h

niet ernstig

niet gevonden

Over het algemeen wordt er geen verschil gezien tussen lage intra-abdominale druk en standaard druk. Een paar studies zien een significant verschil, maar dit is (vaak) niet klinisch relevant

⨁⨁◯◯
LAAG

CRUCIAAL

Longfunctie

12

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^h

niet ernstig

niet gevonden

Het grootste deel van de studies toont geen verschil, of het verschil is niet klinisch relevant.

⨁⨁◯◯
LAAG

CRUCIAAL

Trombo-embolisch event

2

gerandomiseerde trials

ernstig ^a

niet ernstig

zeer ernstig ^d,i

niet ernstig

niet gevonden

Voor het grootste deel van de trombotische parameters wordt geen verschil gezien.

⨁◯◯◯
ZEER LAAG

BELANGRIJK

Kwaliteit chirurgische condities - Schaal

7

gerandomiseerde trials

zeer ernstig ^a,j

niet ernstig

niet ernstig

niet ernstig

niet gevonden

4 studies zagen geen verschil in chirurgische condities, 2 studies zagen slechtere condities. 1 studie zag een nadeel bij technische moeilijkheid en werkgebied, maar geen verschil voor zichtbaarheid en chirurgische pijn.

⨁⨁◯◯
LAAG

CRUCIAAL

Kwaliteit chirurgische condities - Conversie naar standaard druk

12

gerandomiseerde trials

zeer ernstig ^a,j

niet ernstig

niet ernstig

niet ernstig

niet gevonden

In 4-30% van de gevallen moest de druk opgehoogd worden om de operatie af te kunnen maken.

⨁⨁◯◯
LAAG

CRUCIAAL

Veiligheid

20

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

zeer ernstig ^k

niet gevonden

Er wordt geen verschil in complicaties gezien

⨁◯◯◯
ZEER LAAG

CRUCIAAL

Herstel

15

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^d

niet ernstig

niet gevonden

14 studies zagen geen verschil, 3 studies zagen een kortere opnameduur/algemeen herstel.

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LAAG

BELANGRIJK

Misselijkheid en braken

8

gerandomiseerde trials

ernstig ^a

niet ernstig

ernstig ^f

niet ernstig

niet gevonden

Over het algemeen wordt er geen verschil gezien voor deze uitkomstmaat

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LAAG

BELANGRIJK

Certainty assessment

Aantal patiënten

Effect

Certainty

Importantie

Aantal studies

Studieopzet

Risk of bias

Inconsistentie

Indirect bewijs

Onnauwkeurigheid

Andere factoren

Diepe NMB

Normale NMB

Relatief
(95% CI)

Absoluut
(95% CI)

Chirurgische condities - Lage IAP + diepe NMB versus lage IAP + normale NMB

6

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

ernstig ^b

niet gevonden

146

166

-

SMD 0.63 SD hoger
(0.06 hoger tot 1.19 hoger)

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LAAG

Chirurgische condities - Lage IAP + diepe NMB versus standaard IAP + diepe NMB

3

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

ernstig ^b

niet gevonden

65

104

-

SMD 1.13 SD lager
(1.47 lager tot 0.79 lager)

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LAAG

Chirurgische condities - Lage IAP + diepe NMB versus standaard IAP + normale NMB

2

gerandomiseerde trials

ernstig ^a

niet ernstig

niet ernstig

ernstig ^b

niet gevonden

32

73

-

SMD 0.87 SD lager
(1.3 lager tot 0.43 lager)

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LAAG

Postoperatieve pijn

5

gerandomiseerde trials

ernstig ^a

ernstig ^c

niet ernstig

zeer ernstig ^b,d

niet gevonden

158

200

-

SMD 0.14 SD lager
(0.51 lager tot 0.23 hoger)

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ZEER LAAG