Use Of Low-pressure Pneumoperitoneum Research Articles

Low Pressure versus Standard Pressure Pneumoperitoneum in Laparoscopic Appendectomy: A Randomized Controlled Trial.

The creation of pneumoperitoneum using higher pressure is believed to be associated with increased postoperative abdominal pain. This study aimed to compare postoperative abdominal pain following low pressure laparoscopic appendectomy and standard pressure laparoscopic appendectomy. This was a prospective, double-blind, randomized controlled trial of 54 patients aged between 18 and 56 years with clinical and/or radiologic diagnosis of acute appendicitis. The patients were randomly allocated to two groups: low pressure laparoscopic appendectomy (n = 26) and standard pressure laparoscopic appendectomy (n = 28). The intra-abdominal pressure was kept in either low pressure (9 mm Hg) or standard pressure (13 mm Hg). Abdominal and shoulder pain scores were assessed using the visual analog scale at 6 hours and 3 days post procedure. Postoperative analgesia requirement, duration of surgery, complications, and hospital stay were recorded. Both groups match for the demographic parameters. Three patients required conversion from low to standard pressure. There was no difference between the two groups in terms of abdominal pain (P = 0.86) and shoulder pain (P = 0.33), duration of surgery (P = 0.51), complications (P = 0.17), and length of hospital stay (P = 0.83). The use of low pressure pneumoperitoneum did not reduce the incidence of abdominal pain in patients who had laparoscopic appendectomy. Patients with acute appendicitis can be treated with either low or normal pressure pneumoperitoneum depending on the experience of the surgeon.

Quality of recovery in patients under low- or standard-pressure pneumoperitoneum. A randomised controlled trial.

The use of low-pressure pneumoperitoneum seems to be capable of reducing complications such as post-operative pain. However, the quality of evidence supporting this conclusion is low. Both the lack of investigator blinding to both intra-abdominal pressure and to method of neuromuscular blockade represent key sources of bias. Hence, this prospective, randomised, and double-blind study aimed to compare the quality of recovery (Questionnaire QoR-40) of patients undergoing laparoscopic cholecystectomy under low-pressure and standard-pressure pneumoperitoneum. We tested the hypothesis that low pneumoperitoneum pressure enhances the quality of recovery following LC. Eighty patients who underwent elective laparoscopic cholecystectomy were randomly divided into two groups, a low-pressure (10mm Hg) pneumoperitoneum group and a standard-pressure (14mm Hg) pneumoperitoneum group. For all participants, the value of the insufflation pressure was kept hidden and only the nurse responsible for the operating room was aware of it. Deep neuromuscular blockade was induced for all cases [train-of-four (TOF) = 0; post-tetanic count (PTC) > 0]. The quality of recovery was assessed on the morning of first post-operative day. No difference was found in either total score or in its different dimensions according to the QoR-40 questionnaire. The patients in the low-pressure pneumoperitoneum group experienced more pain during forced coughing measured at 4hours (median difference [95% CI], 1 [0-2]; P=.030), 8hours (1 [0-2]; P=.030) and 12hours (0 [0-1] P=.025) after discharge from the post-anaesthesia care unit, when compared with those in the standard-pressure pneumoperitoneum group. We thus conclude that the use of low-pressure pneumoperitoneum during elective laparoscopic cholecystectomy does not improve the quality of recovery.

A Randomized Trial of Low-Pressure (08–10 mm Hg) vs. Standard-Pressure (13–15 mm Hg) Pneumoperitoneum in Laparoscopic Cholecystectomy

The reported incidence of shoulder tip pain after laparoscopic cholecystectomy was 30%–50%. The aim of the present randomized controlled study was to compare the effects of low-pressure (08–10 mm Hg) vs. standard-pressure (13–15 mm Hg) pneumoperitoneum in patients undergoing laparoscopic cholecystectomy. One hundred patients between 18 and 70 years undergoing laparoscopic cholecystectomy were included. Group A and group B patients underwent low-pressure and standard-pressure pneumoperitoneum laparoscopic cholecystectomy respectively. Post-operative shoulder tip pain and post-operative abdominal pain were measured using visual analogue scale score at 2 h, 8 h, 24 h and 48 h after surgery. The primary outcome measures were the incidence and severity of post-operative shoulder tip pain, whereas secondary outcome measures were the incidence and severity of abdominal pain. Intergroup comparison of categorical and continuous variables was done using the chi-square test/Fisher’s exact test and unpaired ‘t’ test respectively. The incidence and severity of post-operative shoulder tip pain at 2 h, 8 h, 24 h and 48 h was significantly higher in group B as compared to group A. The incidence of post-operative abdominal pain at 48 h was significantly higher in group B as compared to group A. The severity of post-operative abdominal pain at 24 h and 48 h was significantly higher in group B as compared to group A. Low-pressure laparoscopic cholecystectomy significantly decreases the incidence and severity of post-operative shoulder tip and abdominal pain. Routine use of low-pressure pneumoperitoneum for the alleviation of post-operative pain following laparoscopic cholecystectomy is recommended.

Effects of pneumoperitoneum on kidney injury biomarkers: A randomized clinical trial.

BackgroundIncreased intra-abdominal pressure causes hemodynamic changes that may affect renal biomarkers.MethodsThis randomized, single-blind, single-center clinical trial recruited patients undergoing laparoscopic cholecystectomy at a tertiary care center in Brazil. They were randomly allocated to a standard intra-abdominal pressure group (P10-12, 10–12 mm Hg) and a low intra-abdominal pressure group (P6-8, 6–8 mm Hg). The primary outcome was the change in neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C levels measured at the beginning of the procedure (T0), at the end of the procedure (T1), and 24 hours after the procedure (T2). P-values < 0.05 were considered statistically significant.ResultsIn total, 64 patients completed the study—33 were given standard pressure and 31 were given low pressure. There was no significant difference in the biomarker between the groups (P = 0.580), but there was a significant difference between the time points with elevation at T1 (P < 0.001). Similar to NGAL, cystatin C had an elevation at T1 in both groups (P = 0.021), but no difference was found when comparing the groups.ConclusionsIn laparoscopic cholecystectomy, pneumoperitoneum increases NGAL and cystatin C levels intraoperatively, and the use of low-pressure pneumoperitoneum does not change the course of these biomarkers.

Effect of pneumoperitoneum pressure and the depth of neuromuscular block on renal function in patients with diabetes undergoing laparoscopic pelvic surgery: study protocol for a double-blinded 2 \xd7 2 factorial randomized controlled trial

BackgroundPatients with diabetes mellitus are at a high risk of developing postoperative acute kidney injury. For patients receiving laparoscopic surgery, standard-pressure pneumoperitoneum (SPP) currently applied in clinical practice also undermines renal perfusion. Several studies have shown that low-pressure pneumoperitoneum (LPP) might reduce pressure-related ischemic renal injury. However, LPP may compromise the view of the surgical field. Previous studies have indicated that deep neuromuscular blockade (NMB) can ameliorate this issue. However, the conclusion is still uncertain. The hypothesis of this study is that the joint use of LPP and deep NMB can reduce perioperative renal injury in diabetic patients undergoing laparoscopic pelvic surgery without impeding the view of the surgical field.MethodsThis is a double-blinded, randomized controlled trial using a 2 × 2 factorial trial design. A total of 648 diabetes patients scheduled for major laparoscopic pelvic surgeries at Peking Union Medical College Hospital will be randomized into the following four groups: SPP (12–15 mmHg) + deep-NMB (post-tetanic count of 1–2) group, LPP (7–10 mmHg) + deep-NMB group, SPP + moderate-NMB (train-of-four of 1–2) group, and LPP + moderate-NMB group. The primary outcome is serum cystatin C level measured before insufflation, after deflation, 24 h postoperatively, and 72 h postoperatively. The secondary outcomes are serum creatinine level, intraoperative urine output, erythrocytes in urinary sediment, renal tissue oxygen saturation, Leiden’s surgical condition rating scale, surgery duration, and occurrence of bucking or body movement.DiscussionThis study will provide evidence for the effect of LPP on renal function protection in patients with diabetes undergoing laparoscopic pelvic surgery. The trial can also help us to understand whether deep NMB can improve surgical conditions.Trial registrationClinicalTrials.gov: NCT04259112. Prospectively registered on 5 February 2020.

Low pressure versus standard pressure pneumoperitoneum in laparoscopic cholecystectomy: a comparative study

Background: With the establishment of laparoscopic cholecystectomy as gold standard management of cholelithiasis, the current stress is being given on increasing patient safety and reducing the post-operative morbidity associated with this procedure. An emerging trend is to use of low-pressure pneumoperitoneum in an attempt to lower the impact of pneumoperitoneum while providing adequate working space.Methods: In this prospective randomized study 66 participants were allocated into two arms i.e. low-pressure pneumoperitoneum (LPP) and standard pressure pneumoperitoneum (SPP). The necessary data were collected using laboratory investigations, clinical examination and perioperative findings. Data were analyzed using suitable statistical software.Results: Mean duration of surgery, surgical difficulty and field visualization difficulty were insignificantly greaterin LPP group than SPP group. CO2 consumption was significantly less in LPP. Incidence of bile spillage, usage of drain was insignificantly increased in LPP. Post-operative pain was significantly greater in SPP group. Time for per oral tolerance of food and incidence of nausea were significantly greater in SPP group. Standard pressure group needed significantly more tramadol injection than LPP. There were no significant haemodynamic changes in SPP group compared to LPP group. Length of hospital stay was significantly greater in SPP.Conclusions: Laparoscopic cholecystectomy in low pressure pneumoperitoneum is safe and feasible. Intra-operative complications like operative field visualization, operative difficulties, conversion rates, duration of surgery are not affected moreover, low-pressure pneumoperitoneum, decreases consumption of intra-operative CO2, post-operative pain, shoulder tip pain, need of analgesia, nausea and promotes early per oral feeding, thus reduces hospital stay.

Pain after laparoscopic surgery: Focus on shoulder-tip pain after gynecological laparoscopic surgery.

Laparoscopy, one of minimally invasive procedures, is a commonly used procedure in diagnosis and management of various kinds of clinical problems, including gynecologic organ-related diseases. Compared with conventional exploratory laparotomy, the benefits of laparoscopic surgery include reduction of surgical wound, decreasing in postoperative pain, shortening hospital stay, rapid recovery, and a better cosmetic result. However, there are still up to 80% of patients after laparoscopic surgery complaining of high levels of pain and needing pain relief. Postlaparoscopic pain can be separated into distinct causes, such as surgical trauma- or incision wound-associated inflammatory change, and pneumoperitoneum (carbon dioxide [CO2])-related morphological and biochemical changes of peritoneum and diaphragm. The latter is secondary to irritation, stretching, and foreign body stimulation, leading to phrenic neuropraxia and subsequent shoulder-tip pain (STP). STP is the most typical unpleasant experience of patients after laparoscopic surgery. There are at least 11 strategies available to attempt to decrease postlaparoscopic STP, including (1) the use of an alternative insufflating gas in place of CO2, (2) the use of low-pressure pneumoperitoneum in place of standard-pressure pneumoperitoneum, (3) the use of warmed or warmed and humidified CO2, (4) gasless laparoscopy, (5) subdiaphragmatic intraperitoneal anesthesia, (6) local intraperitoneal anesthesia, (7) actively expelling out of gas, (8) intraperitoneal drainage, (9) fluid instillation, (10) pulmonary recruitment maneuvers, and (11) others and combination. The present article is limited in discussing postlaparoscopic STP. We extensively review published articles to provide a better strategy to reduce postlaparoscopic STP.

Effect of Pneumoperitoneum on Renal Resistive Index and Renal Function in Patients Who Have Undergone Laparoscopic Living Donor Nephrectomy: A Pilot Study

IntroductionThe use of low-pressure pneumoperitoneum during laparoscopic living donor nephrectomy (LLDN) was assumed to cause less renal damage compared to high-pressure pneumoperitoneum. This study aims to evaluate the effect of low vs high-pressure pneumoperitoneum during LLDN on renal function and renal resistive index (RRI), which has never been done before. Materials and MethodsThe subjects were divided into 2 groups, low-pressure (8–10 mmHg) and high-pressure pneumoperitoneum (12–14 mmHg). The RRI, serum creatinine, and estimated glomerular filtration rate were measured during the perioperative period. ResultsA total of 45 samples were analyzed in this study: 17 subjects in the low-pressure pneumoperitoneum group and 28 subjects in the high-pressure group. RRI levels remained within the normal range (< .80) with no significant difference observed between the 2 groups (P > .05) before surgery, intraoperatively, or post-surgery. The preoperative and postoperative serum creatinine and glomerular filtration rate were similar in both groups. ConclusionsThe use of low-pressure pneumoperitoneum had no benefit compared to high-pressure pneumoperitoneum in preserving RRI and function in LLDN.

Comparative Analysis of Hemodynamic Changes and Shoulder Tip Pain Under Standard Pressure Versus Low-pressure Pneumoperitoneum in Laparoscopic Cholecystectomy.

ABSTRACTBackgroundLaparoscopic cholecystectomy is the gold standard procedure for cholelithiasis. Pneumoperitoneum is created using carbon dioxide (CO2) which is usually maintained at a range of 12-14 mm Hg. An emerging trend has been the use of low-pressure pneumoperitoneum in the range of 7-10 mm Hg in an attempt to lower the impact of pneumoperitoneum on the human physiology while providing adequate working space. Our study proposes to compare the effects of low-pressure pneumoperitoneum with the use of standard pressure of pneumoperitoneum.Aims and objectiveTo compare and analyze various factors like blood pressure, heart rate, end-tidal CO2 and postoperative shoulder tip pain in cases undergoing laparoscopic cholecystectomy using standard pressure versus low pressure.Materials and methodsThis is a prospective randomized study carried out at Santosh Medical College and Hospitals, Ghaziabad from September 2017 to December 2018. This study included 60 patients of cholelithiasis which were divided into two groups of 30 patients each. Group I was offered laparoscopic cholecystectomy under standard pressure pneumoperitoneum and group II underwent laparoscopic cholecystectomy using low-pressure pneumoperitoneum. Patients in each group were evaluated for various intraoperative physiological changes and postoperative shoulder tip pain.Observations and resultsCholelithiasis is commonly seen in middle-aged females. There is no significant difference in duration of surgery between the two groups. However, various factors like systolic blood pressure, heart rate, end-tidal CO2 were significantly better in the low-pressure group. Postoperative shoulder tip pain (measured by VAS scoring system) was significantly less in the low-pressure group during the first 24 hours.ConclusionLaparoscopic cholecystectomy under low-pressure pneumoperitoneum causes minimal physiological changes and less postoperative shoulder tip pain.How to cite this articleGoel A, Gupta S, et al. Comparative Analysis of Hemodynamic Changes and Shoulder Tip Pain Under Standard Pressure Versus Low-pressure Pneumoperitoneum in Laparoscopic Cholecystectomy. Euroasian J Hepatogastroenterol 2019;9(1): 5-8.

Insufflation pressure and its effect on shoulder tip pain after laparoscopic cholecystectomy – A single-blinded, randomised study on 200 patients

ObjectiveThe origin of shoulder tip pain (STP) after laparoscopic cholecystectomy (LC) is multifactorial and poorly understood. Although many researchers studied the effect of low-pressure pneumoperitoneum on incidence and severity of shoulder pain, the role of low-pressure pneumoperitoneum on shoulder pain remains controversial. MethodsThis was a single-blinded, randomised study to find out correlation of insufflation pressure on STP after LC in a tertiary care hospital in New Delhi. A total of 200 patients were included in the study. One hundred patients were included in the low-pressure group (8–10 mmHg), and 100 patients were part of the standard-pressure group (13–15 mmHg). All the patients were evaluated for the incidence and severity of STP in a time frame of 48 h, i.e., 4 h, 24 h and 48 h. ResultsIncidence of STP was 24.0% in the standard-pressure group and 20.2% in the low-pressure group. The incidence and severity of STP were not statistically significant between standard-pressure and low-pressure groups at 4 h, 24 h and 48 h postoperatively. Operative difficulty due to constraint of space (7.4%) was significantly high in the low-pressure group. ConclusionReducing the pressure of the pneumoperitoneum to 8–10 mmHg did not lower the incidence and intensity of postoperative STP. It can jeopardise the surgeon's comfort because of inadequate exposure. Routine use of low-pressure pneumoperitoneum in LC cannot be recommended.

Comparison of Outcome Between Low Pressure and Standard Pressure Pneumoperitoneum in Laparoscopic Living Donor Nephrectomy

Nowadays, kidney transplantation is done through laparoscopic living donor nephrectomy performed by insufflating CO2 gas into intraperitoneum space using standard pressure (12–15 mmHg). However, it is also hypothesized that with lower pressure (8–10 mmHg) could be used for laparoscopic living donor nephrectomy related with lower postoperative pain and side effects. This was a prospective comparative study done in Department of Urology, Cipto Mangunkusumo General Hospital from November 2015 to August 2016. All subjects underwent laparoscopic living donor nephrectomy (LLDN). In this period, the subjects received a low pressure pneumoperitoneum procedure. This group was later compared randomly to a standard pressure pneumoperitoneum procedure group who underwent previous LLDN procedure. Out of 85, subjects underwent LLDN with low and standard pressure were 41 and 44, respectively. Despite nonsignificant difference of post op pain and duration of operation, the side effect in low pressure was lower than standard (p = 0.033 for epigastric pain, p = 0.024 for nausea, and p = 0.018 for vomiting). However, 22% subjects with low pressure need to be converted to standard pressure. Based on stratified analysis, the cause of conversion was higher BMI (p &lt; 0.001). In conclusion, LLDN using low pressure pneumoperitoneum is proven to be as effective as LLDN using standard pressure pneumoperitoneum in providing good intraoperative and postoperative outcomes. Thus, this study suggests the use of low pressure pneumoperitoneum as an alternative procedure in LLDN surgeries. Further studies, however, are needed to assess the adverse outcomes of LLDN procedure using low pressure, as well as to assess the risk of conversion to standard pressure, i.e., BMI.

Deep neuromuscular blockade improves surgical conditions during low-pressure pneumoperitoneum laparoscopic donor nephrectomy

BackgroundEvidence indicates that low-pressure pneumoperitoneum (PNP) reduces postoperative pain and analgesic consumption. A lower insufflation pressure may hamper visibility and working space. The aim of the study is to investigate whether deep neuromuscular blockade (NMB) improves surgical conditions during low-pressure PNP.MethodsThis study was a blinded randomized controlled multicenter trial. 34 kidney donors scheduled for laparoscopic donor nephrectomy randomly received low-pressure PNP (6 mmHg) with either deep (PTC 1–5) or moderate NMB (TOF 0–1). In case of insufficient surgical conditions, the insufflation pressure was increased stepwise. Surgical conditions were rated by the Leiden-Surgical Rating Scale (L-SRS) ranging from 1 (extremely poor) to 5 (optimal).ResultsMean surgical conditions were significantly better for patients allocated to a deep NMB (SRS 4.5 versus 4.0; p < 0.01). The final insufflation pressure was 7.7 mmHg in patients with deep NMB as compared to 9.1 mmHg with moderate NMB (p = 0.19). The cumulative opiate consumption during the first 48 h was significantly lower in patients receiving deep NMB, while postoperative pain scores were similar. In four patients allocated to a moderate NMB, a significant intraoperative complication occurred, and in two of these patients a conversion to an open procedure was required.ConclusionsOur data show that deep NMB facilitates the use of low-pressure PNP during laparoscopic donor nephrectomy by improving the quality of the surgical field. The relatively high incidence of intraoperative complications indicates that the use of low pressure with moderate NMB may compromise safety during LDN. Clinicaltrials.gov identifier: NCT 02602964.

MP52-02 DOES PNEUMOPERITONEUM CAUSE TRANSIENT RENAL INJURY IN CHILDREN?

You have accessJournal of UrologySurgical Technology & Simulation: Instrumentation & Technology I1 Apr 2017MP52-02 DOES PNEUMOPERITONEUM CAUSE TRANSIENT RENAL INJURY IN CHILDREN? Julia Finkelstein, Solomon Woldu, Alexander Small, Nina Mikkilineni, Sarah Lambert, and Pasquale Casale Julia FinkelsteinJulia Finkelstein More articles by this author , Solomon WolduSolomon Woldu More articles by this author , Alexander SmallAlexander Small More articles by this author , Nina MikkilineniNina Mikkilineni More articles by this author , Sarah LambertSarah Lambert More articles by this author , and Pasquale CasalePasquale Casale More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1632AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Laparoscopic and robotic surgeries are increasingly utilized in pediatric urology. The associated pneumoperitoneum increases intra-abdominal pressure (IAP), decreases systemic cardiac output and diminishes renal blood flow. This hypoperfusion may result in transient renal injury. The purpose of this study was to assess the short-term impact of pneumoperitoneum on renal function in children using sequential creatinine and cystatin C assays. METHODS Prospective analysis of all children over 12 months old who underwent laparoscopic or robotic surgery at a single institution between 9/2014 and 7/2015. For each patient, blood samples were obtained in the OR immediately prior to surgery, upon transfer to the recovery room, and on the morning of POD 1 if the child stayed overnight. Intraoperative parameters, including anesthesia time (a subset of total surgical time), were recorded. The IAP was maintained at 8 mmHg for children <10 years old and at 10 mmHg for older patients. Paired t tests and linear regression were performed for statistical analysis. RESULTS Over the 10-month study period, 20 children underwent laparoscopic (25%) or robotic (75%) surgery. 75% were boys. Patient and intraoperative characteristics are detailed in the table. The mean preoperative, immediate postoperative and POD 1 cystatin C values were 0.71 +/- 0.12, 0.65 +/- 0.10 and 0.60 +/- 0.12, respectively. Likewise, creatinine values were 0.35 +/-0.17, 0.41 +/- 0.18, and 0.36 +/- 0.17. There was no significant difference in cystatin C or creatinine values between the study time points. Linear regression analysis did not demonstrate an association between anesthesia time and postoperative creatinine or cystatin C values. CONCLUSIONS Pneumoperitoneum does not appear to affect renal function in children undergoing laparoscopic or robotic surgery. This study provides support for the use of low-pressure pneumoperitoneum and next generation valveless trocar systems. However, further investigation is warranted, given the limited sample size and relatively short duration of surgeries. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e703 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Julia Finkelstein More articles by this author Solomon Woldu More articles by this author Alexander Small More articles by this author Nina Mikkilineni More articles by this author Sarah Lambert More articles by this author Pasquale Casale More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Deep Neuromuscular Block to Optimize Surgical Space Conditions During Laparoscopic Surgery

Neuromuscular block (NMB) is frequently used in abdominal surgery to improve surgical conditions by relaxation of the abdominal wall and prevention of sudden muscle contractions. The evidence supporting routine use of deep NMB is still under debate. We aimed to provide evidence for the superiority of routine use of deep NMB during laparoscopic surgery. We performed a systematic review and meta-analysis of studies comparing the influence of deep vs moderate NMB during laparoscopic procedures on surgical space conditions and clinical outcomes. Trials were identified from Medline, Embase, and Central databases from inception to December 2016. We included randomized trials, crossover studies, and cohort studies. Our search yielded 12 studies on the effect of deep NMB on the surgical space conditions. Deep NMB during laparoscopic surgeries improves the surgical space conditions when compared with moderate NMB, with a mean difference of 0.65 (95% confidence interval (CI): 0.47-0.83) on a scale of 1-5, and it facilitates the use of low-pressure pneumoperitoneum. Furthermore, deep NMB reduces postoperative pain scores in the postanaesthesia care unit, with a mean difference of - 0.52 (95% CI: -0.71 to - 0.32). Deep NMB improves surgical space conditions during laparoscopic surgery and reduces postoperative pain scores in the postanaesthesia care unit. Whether this leads to fewer intraoperative complications, an improved quality of recovery, or both after laparoscopic surgery should be pursued in future studies. The review methodology was specified in advance and registered at Prospero on July 27, 2016, registration number CRD42016042144.

What is the evidence for the use of low-pressure pneumoperitoneum? A systematic review.

BackgroundLaparoscopic surgery has several advantages when compared to open surgery, including faster postoperative recovery and lower pain scores. However, for laparoscopy, a pneumoperitoneum is required to create workspace between the abdominal wall and intraabdominal organs. Increased intraabdominal pressure may also have negative implications on cardiovascular, pulmonary, and intraabdominal organ functionings. To overcome these negative consequences, several trials have been performed comparing low- versus standard-pressure pneumoperitoneum.MethodsA systematic review of all randomized controlled clinical trials and observational studies comparing low- versus standard-pressure pneumoperitoneum.Results and conclusionsQuality assessment showed that the overall quality of evidence was moderate to low. Postoperative pain scores were reduced by the use of low-pressure pneumoperitoneum. With appropriate perioperative measures, the use of low-pressure pneumoperitoneum does not seem to have clinical advantages as compared to standard pressure on cardiac and pulmonary function. Although there are indications that low-pressure pneumoperitoneum is associated with less liver and kidney injury when compared to standard-pressure pneumoperitoneum, this does not seem to have clinical implications for healthy individuals. The influence of low-pressure pneumoperitoneum on adhesion formation, anastomosis healing, tumor metastasis, intraocular and intracerebral pressure, and thromboembolic complications remains uncertain, as no human clinical trials have been performed. The influence of pressure on surgical conditions and safety has not been established to date. In conclusion, the most important benefit of low-pressure pneumoperitoneum is lower postoperative pain scores, supported by a moderate quality of evidence. However, the quality of surgical conditions and safety of the use of low-pressure pneumoperitoneum need to be established, as are the values and preferences of physicians and patients regarding the potential benefits and risks. Therefore, the recommendation to use low-pressure pneumoperitoneum during laparoscopy is weak, and more studies are required.

Comparison of Standard-pressure and Low-pressure Pneumoperitoneum in Laparoscopic Cholecystectomy

With the safety of laparoscopic cholecystectomy (LC) having been established, the current stress is on reducing the postoperative morbidity associated with this procedure. Hence, this study was undertaken to compare the effect of low-pressure (8 mm Hg) (LPLC) versus standard-pressure (12 mm Hg) (SPLC) pneumoperitoneum on postoperative pain, respiratory and liver functions, the stress response, and the intraoperative surgeon comfort in patients undergoing LC. Patients undergoing LC (n=43) were randomized into the LPLC (8 mm Hg) group (n=22) and the SPLC (12 mm Hg) group (n=21). Postoperative pain, changes in liver function, peak expiration flow rate, C-reactive protein level, and intraoperative surgeon comfort were assessed. The postoperative pain scores (P=0.003, 0.000, 0.001, and 0.002 at 0, 4, 8, and 24 h), total analgesic requirement (P=0.001), and the number (total and good) of demands for analgesic in the first 24 hours (P=0.002 and 0.001) were lower in the LPLC group. The surgeon comfort in the LPLC group was significantly lesser (P=0.000). The liver function and peak expiration flow rate did not show any significant changes. C-reactive protein levels varied significantly only at 24 hours postoperatively (P=0.001). The use of low-pressure pneumoperitoneum (8 mm Hg) for LC is associated with a significantly lower postoperative pain. However, the use of this low-pressure pneumoperitoneum can jeopardize the surgeon's comfort.

Low pressure versus standard pressure pneumoperitoneum in laparoscopic cholecystectomy.

A pneumoperitoneum of 12 to 16 mm Hg is used for laparoscopic cholecystectomy. Lower pressures are claimed to be safe and effective in decreasing cardiopulmonary complications and pain. To assess the benefits and harms of low pressure pneumoperitoneum compared with standard pressure pneumoperitoneum in people undergoing laparoscopic cholecystectomy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until February 2013 to identify randomised trials,using search strategies. We considered only randomised clinical trials, irrespective of language, blinding, or publication status for inclusion in the review. Two review authors independently identified trials and independently extracted data. We calculated the risk ratio (RR), mean difference (MD), or standardised mean difference (SMD) with 95% confidence intervals (CI) using both fixed-effect and random-effects models with RevMan 5 based on available case analysis. A total of 1092 participants randomly assigned to the low pressure group (509 participants) and the standard pressure group (583 participants) in 21 trials provided information for this review on one or more outcomes. Three additional trials comparing low pressure pneumoperitoneum with standard pressure pneumoperitoneum (including 179 participants) provided no information for this review. Most of the trials included low anaesthetic risk participants undergoing elective laparoscopic cholecystectomy. One trial including 140 participants was at low risk of bias. The remaining 20 trials were at high risk of bias. The overall quality of evidence was low or very low. No mortality was reported in either the low pressure group (0/199; 0%) or the standard pressure group (0/235; 0%) in eight trials that reported mortality. One participant experienced the outcome of serious adverse events (low pressure group 1/179, 0.6%; standard pressure group 0/215, 0%; seven trials; 394 participants; RR 3.00; 95% CI 0.14 to 65.90; very low quality evidence). Quality of life, return to normal activity, and return to work were not reported in any of the trials. The difference between groups in the conversion to open cholecystectomy was imprecise (low pressure group 2/269, adjusted proportion 0.8%; standard pressure group 2/287, 0.7%; 10 trials; 556 participants; RR 1.18; 95% CI 0.29 to 4.72; very low quality evidence) and was compatible with an increase, a decrease, or no difference in the proportion of conversion to open cholecystectomy due to low pressure pneumoperitoneum. No difference in the length of hospital stay was reported between the groups (five trials; 415 participants; MD -0.30 days; 95% CI -0.63 to 0.02; low quality evidence). Operating time was about two minutes longer in the low pressure group than in the standard pressure group (19 trials; 990 participants; MD 1.51 minutes; 95% CI 0.07 to 2.94; very low quality evidence). Laparoscopic cholecystectomy can be completed successfully using low pressure in approximately 90% of people undergoing laparoscopic cholecystectomy. However, no evidence is currently available to support the use of low pressure pneumoperitoneum in low anaesthetic risk patients undergoing elective laparoscopic cholecystectomy. The safety of low pressure pneumoperitoneum has to be established. Further well-designed trials are necessary, particularly in people with cardiopulmonary disorders who undergo laparoscopic cholecystectomy.

Effects of Varying Intraperitoneal Pressure on Liver Function Tests During Laparoscopic Cholecystectomy

Laparoscopic cholecystectomy at standard-pressure pneumoperitoneum uses a pressure of 12-14 mm Hg, which may cause a variety of adverse physiological changes involving the respiratory, cardiovascular, and hepatorenal systems reflected as subclinical abnormalities in biochemical parameters. The use of low-pressure pneumoperitoneum in the range of 8-10 mm Hg has been shown to reduce the adverse physiological changes without affecting the outcome of surgery. This study was done in a randomized controlled manner. Patients with gallstone disease (n=101) underwent laparoscopic cholecystectomy. Patients were randomly assigned to high-pressure laparoscopic cholecystectomy (HPLC) (n=51) and low-pressure laparoscopic cholecystectomy (LPLC) (n=50) and underwent surgery at pressures of 14 mm Hg and 8 mm Hg, respectively. Liver function tests, including total bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase, were obtained preoperatively and on postoperative Days 1 and 7. The two study groups had similar demographic profiles, and there were no significant differences in the operative time (HPLC, 47.25 ± 6.73 minutes; LPLC, 48.00 ± 7.76 minutes; P=.6071) and pneumoperitoneum time (HPLC, 34.02 ± 5.29 minutes; LPLC, 34.60 ± 6.13 minutes; P=.6115). On postoperative Day 1, the total bilirubin levels were 1.0684 ± 0.4108 mg/dL and 0.8926 ± 0.3162 mg/dL for HPLC and LPLC (P=.0179), respectively, AST levels were 66.0810 ± 25.5868 IU/L and 42.2420 ± 14.7301 IU/L (P=.0001), respectively, and ALT levels were 68.1410 ± 31.4572 IU/L and 42.7460 ± 17.9405 IU/L (P=.0001), respectively. Thus, liver enzyme activities were significantly elevated in the HPLC group compared with the LPLC group. LPLC causes less abnormality in liver function tests in the postoperative period compared with HPLC. LPLC should be considered in all patients undergoing laparoscopic cholecystectomy, especially those patients with compromised liver functions.

Natural-orifice transluminal endoscopic surgery: low-pressure pneumoperitoneum is sufficient and is associated with an improved cardiopulmonary response (PressurePig Study)

The aim of this randomized trial in the acute porcine model was to compare the quality of transgastric peritoneoscopy with the use of low-pressure versus standard-pressure pneumoperitoneum and to evaluate the respective associated cardiopulmonary changes. For transgastric peritoneoscopy, carbon dioxide was insufflated via the endoscope for a constant intraperitoneal pressure of 6 mmHg or 12 mmHg in 9 pigs each. The quality of transgastric peritoneoscopy was rated on a visual analog scale (0 mm, min.; 100 mm, max.) by the endoscopist, who was blinded to the intraperitoneal pressure. The cardiac index and global end-diastolic volume index (GEDVI, reflecting preload) were measured every 3 minutes by transpulmonary thermodilution. The following were also recorded: heart rate, mean arterial pressure (MAP), systemic vascular resistance index (SVRI, reflecting afterload), peak inspiratory pressure (PIP), pH, PCO (2), and PO (2). The quality of transgastric peritoneoscopy with the use of low-pressure pneumoperitoneum was not inferior to that obtained using standard-pressure pneumoperitoneum (87.0 mm vs. 87.3 mm; P<0.05). In both groups we observed a statistically significant rise in MAP and SVRI. The increase in SVRI was less pronounced during low-pressure peritoneum ( P=0.042), indicating a reduced stress response in comparison to standard-pressure peritoneum. There were no relevant differences between the groups in relation to cardiac index, GEDVI, and heart rate. An intra-abdominal pressure of 6 mmHg also led to better oxygenation ( P=0.031 for difference in PO (2) between the two groups) due to lower peak inspiratory pressure ( P<0.001 for difference). There were only slight differences between the groups with regard to pH and PCO (2). Pneumoperitoneum of 12-16 mmHg is used for standard laparoscopy. For NOTES, low-pressure pneumoperitoneum is sufficient and is associated with an improved cardiopulmonary response compared to standard-pressure pneumoperitoneum.

Randomized, prospective comparison of postoperative pain in low‐ versus high‐pressure pneumoperitoneum

Reduced postoperative pain after laparoscopic cholecystectomy (LC) compared to open cholecystectomy (OC) may be able to be further optimized. To reduce pain, focus should be directed on the effects of individual components of pain. A double-blind, randomized, controlled trial was carried out in a tertiary care hospital. Fifty-three elective patients with symptomatic gallstones were enrolled into the study. Patients were randomized to low- or high-pressure pneumoperitoneum groups. In all patients, gas pressure was set to 15 mmHg during placement of ports. Later on, in the low-pressure group, the rest of the procedure was performed at 10 mmHg pressure. At 6 and 24 h postoperatively, a short-form McGill Questionnaire (MPQ) was obtained from all patients. Patients were then asked to complete a 10-cm visual analogue scale (VAS) for abdominal pain. Pain scores were generally low for both groups. Statistical comparisons of mean cumulative McGill score and VAS abdominal pain scores in both groups did not reach statistical significance at 6 and 24 h after operation. There was no correlation between high- and low-pressure laparoscopy and postoperative pain after LC. Peritoneal stretching may be more responsible for shoulder pain but has less effect on intensity of abdominal pain or incisional pain. On the basis of these negative findings, routine use of low-pressure pneumoperitoneum for alleviation of postoperative pain following LC is not recommended.