Helium vs carbon dioxide gas insufflation with or without saline lavage during laparoscopy

Gases for establishing pneumoperitoneum during laparoscopic abdominal surgery

BACKGROUND

This is the second update of a Cochrane Review first published in 2013 and last updated in 2017. Laparoscopic surgery is now widely performed to treat various abdominal diseases. Currently, carbon dioxide is the most frequently used gas for insufflation of the abdominal cavity (pneumoperitoneum). Although carbon dioxide meets most of the requirements for pneumoperitoneum, the absorption of carbon dioxide may be associated with adverse events. Therefore, other gases have been introduced as alternatives to carbon dioxide for establishing pneumoperitoneum.

OBJECTIVES

To assess the safety, benefits, and harms of different gases (e.g. carbon dioxide, helium, argon, nitrogen, nitrous oxide, and room air) used for establishing pneumoperitoneum in participants undergoing laparoscopic abdominal or gynaecological pelvic surgery.

SEARCH METHODS

We searched CENTRAL, Ovid MEDLINE, Ovid Embase, four other databases, and three trials registers on 15 October 2021 together with reference checking, citation searching, and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different gases for establishing pneumoperitoneum in participants (irrespective of age, sex, or race) undergoing laparoscopic abdominal or gynaecological pelvic surgery under general anaesthesia.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 10 RCTs, randomising 583 participants, comparing different gases for establishing pneumoperitoneum: nitrous oxide (four trials), helium (five trials), or room air (one trial) was compared to carbon dioxide. All the RCTs were single-centre studies. Four RCTs were conducted in the USA; two in Australia; one in China; one in Finland; one in Iran; and one in the Netherlands. The mean age of the participants ranged from 27.6 years to 49.0 years. Four trials randomised participants to nitrous oxide pneumoperitoneum (132 participants) or carbon dioxide pneumoperitoneum (128 participants). None of the trials was at low risk of bias. The evidence is very uncertain about the effects of nitrous oxide pneumoperitoneum compared to carbon dioxide pneumoperitoneum on cardiopulmonary complications (Peto odds ratio (OR) 2.62, 95% CI 0.78 to 8.85; 3 studies, 204 participants; very low-certainty evidence), or surgical morbidity (Peto OR 1.01, 95% CI 0.14 to 7.31; 3 studies, 207 participants; very low-certainty evidence). There were no serious adverse events related to either nitrous oxide or carbon dioxide pneumoperitoneum (4 studies, 260 participants; very low-certainty evidence). Four trials randomised participants to helium pneumoperitoneum (69 participants) or carbon dioxide pneumoperitoneum (75 participants) and one trial involving 33 participants did not state the number of participants in each group. None of the trials was at low risk of bias. The evidence is very uncertain about the effects of helium pneumoperitoneum compared to carbon dioxide pneumoperitoneum on cardiopulmonary complications (Peto OR 1.66, 95% CI 0.28 to 9.72; 3 studies, 128 participants; very low-certainty evidence), or surgical morbidity (5 studies, 177 participants; very low-certainty evidence). There were three serious adverse events (subcutaneous emphysema) related to helium pneumoperitoneum (3 studies, 128 participants; very low-certainty evidence). One trial randomised participants to room air pneumoperitoneum (70 participants) or carbon dioxide pneumoperitoneum (76 participants). The trial was at high risk of bias. There were no cardiopulmonary complications, serious adverse events, or deaths observed related to either room air or carbon dioxide pneumoperitoneum.    AUTHORS' CONCLUSIONS: The evidence is very uncertain about the effects of nitrous oxide, helium, and room air pneumoperitoneum compared to carbon dioxide pneumoperitoneum on any of the primary outcomes, including cardiopulmonary complications, surgical morbidity, and serious adverse events. The safety of nitrous oxide, helium, and room air pneumoperitoneum has yet to be established, especially in people with high anaesthetic risk.

Gases for establishing pneumoperitoneum during laparoscopic abdominal surgery

BACKGROUND

This is an update of the review published in 2013.Laparoscopic surgery is now widely performed to treat various abdominal diseases. Currently, carbon dioxide is the most frequently used gas for insufflation of the abdominal cavity (pneumoperitoneum). Although carbon dioxide meets most of the requirements for pneumoperitoneum, the absorption of carbon dioxide may be associated with adverse events. People with high anaesthetic risk are more likely to experience cardiopulmonary complications and adverse events, for example hypercapnia and acidosis, which has to be avoided by hyperventilation. Therefore, other gases have been introduced as alternatives to carbon dioxide for establishing pneumoperitoneum.

OBJECTIVES

To assess the safety, benefits, and harms of different gases (i.e. carbon dioxide, helium, argon, nitrogen, nitrous oxide, and room air) used for establishing pneumoperitoneum in participants undergoing laparoscopic general abdominal or gynaecological pelvic surgery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 9), Ovid MEDLINE (1950 to September 2016), Ovid Embase (1974 to September 2016), Science Citation Index Expanded (1970 to September 2016), Chinese Biomedical Literature Database (CBM) (1978 to September 2016), ClinicalTrials.gov (September 2016), and World Health Organization International Clinical Trials Registry Platform (September 2016).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different gases for establishing pneumoperitoneum in participants (irrespective of age, sex, or race) undergoing laparoscopic abdominal or gynaecological pelvic surgery under general anaesthesia.

DATA COLLECTION AND ANALYSIS

Two review authors identified the trials for inclusion, collected the data, and assessed the risk of bias independently. We performed the meta-analyses using Review Manager 5. We calculated risk ratio (RR) for dichotomous outcomes (or Peto odds ratio for very rare outcomes), and mean difference (MD) or standardised mean difference (SMD) for continuous outcomes with 95% confidence intervals (CI). We used GRADE to rate the quality of evidence, MAIN RESULTS: We included nine RCTs, randomising 519 participants, comparing different gases for establishing pneumoperitoneum: nitrous oxide (three trials), helium (five trials), or room air (one trial) was compared to carbon dioxide. Three trials randomised participants to nitrous oxide pneumoperitoneum (100 participants) or carbon dioxide pneumoperitoneum (96 participants). None of the trials was at low risk of bias. There was insufficient evidence to determine the effects of nitrous oxide and carbon dioxide on cardiopulmonary complications (RR 2.00, 95% CI 0.38 to 10.43; two studies; 140 participants; very low quality of evidence), or surgical morbidity (RR 1.01, 95% CI 0.18 to 5.71; two studies; 143 participants; very low quality of evidence). There were no serious adverse events related to either nitrous oxide or carbon dioxide pneumoperitoneum (three studies; 196 participants; very low quality of evidence). We could not combine data from two trials (140 participants) which individually showed lower pain scores (a difference of about one visual analogue score on a scale of 1 to 10 with lower numbers indicating less pain) with nitrous oxide pneumoperitoneum at various time points on the first postoperative day, and this was rated asvery low quality .Four trials randomised participants to helium pneumoperitoneum (69 participants) or carbon dioxide pneumoperitoneum (75 participants) and one trial involving 33 participants did not state the number of participants in each group. None of the trials was at low risk of bias. There was insufficient evidence to determine the effects of helium or carbon dioxide on cardiopulmonary complications (RR 1.46, 95% CI 0.35 to 6.12; three studies; 128 participants; very low quality of evidence) or pain scores (visual analogue score on a scale of 1 to 10 with lower numbers indicating less pain; MD 0.49 cm, 95% CI -0.28 to 1.26; two studies; 108 participants; very low quality of evidence). There were three serious adverse events (subcutaneous emphysema) related to helium pneumoperitoneum (three studies; 128 participants; very low quality of evidence).One trial randomised participants to room air pneumoperitoneum (70 participants) or carbon dioxide pneumoperitoneum (76 participants). The trial was at unclear risk of bias. There were no cardiopulmonary complications or serious adverse events observed related to either room air or carbon dioxide pneumoperitoneum (both outcomes very low quality of evidence). The evidence of lower hospital costs and reduced pain during the first postoperative day with room air pneumoperitoneum compared with carbon dioxide pneumoperitoneum (a difference of about one visual analogue score on a scale of 1 to 10 with lower numbers indicating less pain, was rated as very low quality of evidence.

AUTHORS' CONCLUSIONS

The quality of the current evidence is very low. The effects of nitrous oxide and helium pneumoperitoneum compared with carbon dioxide pneumoperitoneum are uncertain. Evidence from one trial of small sample size suggests that room air pneumoperitoneum may decrease hospital costs in people undergoing laparoscopic abdominal surgery. The safety of nitrous oxide, helium, and room air pneumoperitoneum has yet to be established.Further trials on this topic are needed, and should compare various gases (i.e. nitrous oxide, helium, argon, nitrogen, and room air) with carbon dioxide under standard pressure pneumoperitoneum with cold gas insufflation for people with high anaesthetic risk. Future trials should include outcomes such as complications, serious adverse events, quality of life, and pain.

Humidification during laparoscopic surgery: overview of the clinical benefits of using humidified gas during laparoscopic surgery

PURPOSE

The peritoneum is the serous membrane that covers the abdominal cavity and most of the intra-abdominal organs. It is a very delicate layer highly susceptible to damage and it is not designed to cope with variable conditions such as the dry and cold carbon dioxide (CO2) during laparoscopic surgery. The aim of this review was to evaluate the effects caused by insufflating dry and cold gas into the abdominal cavity after laparoscopic surgery.

METHODS

A literature search using the Pubmed was carried out. Articles identified focused on the key issues of laparoscopy, peritoneum, morphology, pneumoperitoneum, humidity, body temperature, pain, recovery time, post-operative adhesions and lens fogging.

RESULTS

Insufflating dry and cold CO2 into the abdomen causes peritoneal damage, post-operative pain, hypothermia and post-operative adhesions. Using humidified and warm gas prevents pain after surgery. With regard to hypothermia due to desiccation, it can be fully prevented using humidified and warm gas. Results relating to the patient recovery are still controversial.

CONCLUSIONS

The use of humidified and warm insufflation gas offers a significant clinical benefit to the patient, creating a more physiologic peritoneal environment and reducing the post-operative pain and hypothermia. In animal models, although humidified and warm gas reduces post-operative adhesions, humidified gas at 32 °C reduced them even more. It is clear that humidified gas should be used during laparoscopic surgery; however, a question remains unanswered: to achieve even greater clinical benefit to the patient, at what temperature should the humidified gas be when insufflated into the abdomen? More clinical trials should be performed to resolve this query.

Residual pneumoperitoneum volume and postlaparoscopic cholecystectomy pain

Background:

Gasretention in the peritoneal cavity plays an important role in inducing postoperative pain after laparoscopy, which is inevitably retained in the peritoneal cavity.

Objectives:

The aim of this study was to detect the relation between the volume of residual gas and severity of shoulder and abdominal pain.

Patients and Methods:

In this Prospective study 55 women who were referred for laparoscopic cholecystectomy, were evaluated for the effect of residual pneumoperitoneum on postlaparoscopic cholecystectomy pain intensity. The pneumoperitoneum was graded as absent, mild (1-5 mm), moderate (6-10 mm) and severe (> 11 mm). Patients were followed for postoperative abdominal and shoulder pain using visual analogue scale (VAS), postoperative analgesic requirements, presence of nausea and vomiting, time of unassisted ambulation, time of oral intake and time of return of bowel function in the recovery room and at 6, 12 and 24 hours after operation.

Results:

At the end of the study, 17 patients (30.9%) had no residual pneumoperitoneum after 24 hours; which 23 (41.81%) had mild residual pneumoperitoneum, eight (14.54%) had moderate pneumoperitoneum and seven (12.72%) had severe pneumoperitoneum. Patients with no or mild residual pneumoperitoneum had significantly lower abdominal and shoulder pain scores than whom with moderate to severe pneumoperitoneum (P = 0.00) and need less meperidine requirements (P = 0.00). Patients did not have any significant difference in time of oral intake, return of bowel function, nausea and vomiting percentages.

Conclusions:

We conclude that volume of residual pneumoperitoneum is a contributing factor in the etiology of postoperative pain after laparoscopic cholecystectomy.

Comparing the impact of intraperitoneal hydrocortisone with bupivacaine on postoperative pain after laparoscopic cholecystectomy

Background:

Postoperative pain is a major complaint following laparoscopic cholecystectomy.

Objectives:

The aim of this study was to compare the impact of intraperitoneal hydrocortisone with intraperitoneal bupivacaine on pain relief after laparoscopic cholecystectomy

Patients and Methods:

In a double blind clinical trial, 63 candidates for laparoscopic cholecystectomy were randomly allocated to receive intraperitoneal instillation of either 100 mg bupivacaine in 250 mL normal saline (n = 32) or 100 mg hydrocortisone in 250 mL normal saline (n = 31) before insufflation of CO₂ into the peritoneum for postoperative pain relief. Patients were investigated regarding abdominal and shoulder pain using (visual analog scale) VAS in recovery room and at 6, 12 and 24 hours postoperatively. Patients were also followed regarding postoperative analgesic requirements, nausea and vomiting, and return of bowel function.

Results:

Sixty patients completed the study. Patients in the hydrocortisone group had no statistically significant abdominal and shoulder pain scores compared to the bupivacaine group. The patients were similar regarding postoperative analgesic requirements, return of bowel function, nausea and vomiting. No adverse effect was detected in either group.

Conclusions:

Intraperitoneal administration of hydrocortisone is as effective as bupivacaine to reduce pain and analgesic requirements after laparoscopic cholecystectomy.

Intraperitoneal hydrocortisone for pain relief after laparoscopic cholecystectomy

Background:

Laparoscopic cholecystectomy is associated with shorter hospital stay and less pain in comparison to open surgery. The aim of this study was to evaluate the effect of intraperitoneal hydrocortisone on pain relief following laparoscopic cholecystectomy.

Methods:

Sixty two patients were enrolled in a double-blind, randomized clinical trial. Patients randomly received intraperitoneal instillation of either 250 ml normal saline (n=31) or 100 mg hydrocortisone in 250 ml normal saline (n=31) before insufflation of CO₂ into the peritoneum. Abdominal and shoulder pain were evaluated using VAS after surgery and at 6, 12, and 24 hours postoperatively. The patients were also followed for postoperative analgesic requirements, nausea and vomiting, and return of bowel function.

Results:

Sixty patients completed the study. Patients in the hydrocortisone group had significantly lower abdominal and shoulder pain scores (10.95 vs 12.95; P<0.01). The patients were similar regarding analgesic requirements in the recovery room. However, those in the hydrocortisone group required less meperidine than the saline group (151.66 (±49.9) mg vs 61.66 (±38.69) mg; P=0.00). The patients were similar with respect to return of bowel function, nausea and vomiting. No adverse reaction was observed in either group.

Conclusion:

Intraperitoneal administration of hydrocortisone can significantly decrease pain and analgesic requirements after laparoscopic cholecystectomy with no adverse effects.

Gases for establishing pneumoperitoneum during laparoscopic abdominal surgery

BACKGROUND

Laparoscopic surgery is now widely performed to treat various abdominal diseases. Currently, carbon dioxide is the most frequently used gas for insufflation of the abdominal cavity (pneumoperitoneum). Many other gases have been introduced as alternatives to carbon dioxide for establishing pneumoperitoneum.

OBJECTIVES

To assess the safety, benefits, and harms of different gases for establishing pneumoperitoneum in patients undergoing laparoscopic abdominal surgery.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and Chinese Biomedical Literature Database (CBM) until September 2012.

SELECTION CRITERIA

We only included randomized controlled trials comparing different gases for establishing pneumoperitoneum in patients undergoing laparoscopic abdominal surgery under general anaesthesia.

DATA COLLECTION AND ANALYSIS

Two review authors identified the trials for inclusion, collected the data, and assessed the risk of bias independently. We performed the meta-analyses using Review Manager 5. We calculated the risk ratio (RR) for dichotomous outcomes and the mean difference (MD) or standardized mean difference (SMD) for continuous outcomes with 95% confidence intervals (CI).

MAIN RESULTS

Carbon dioxide pneumoperitoneum versus nitrous oxide pneumoperitoneum Three trials randomized 196 participants (the majority with low anaesthetic risk) to carbon dioxide pneumoperitoneum (n =96) or nitrous oxide pneumoperitoneum (n =100). All of the trials were of high risk of bias. Two trials (n=143) showed lower pain scores in nitrous oxide pneumoperitoneum at various time points on the first post-operative day. One trial (n=53) showed no difference in the pain scores between the groups. There were no significant differences in cardiopulmonary complications, surgical morbidity, or cardiopulmonary changes between the groups. There were no serious adverse events related to either carbon dioxide or nitrous oxide pneumoperitoneum. Carbon dioxide pneumoperitoneum versus helium pneumoperitoneum Four trials randomized 144 participants (the majority with low anaesthetic risk) to carbon dioxide pneumoperitoneum (n =75) or helium pneumoperitoneum (n =69). All of the trials were of high risk of bias. Fewer cardiopulmonary changes were observed with helium pneumoperitoneum than carbon dioxide pneumoperitoneum. There were no significant differences in cardiopulmonary complications, surgical morbidity, or pain scores. There were three serious adverse events (subcutaneous emphysema) related to helium pneumoperitoneum. Carbon dioxide pneumoperitoneum versus any other gas pneumoperitoneum There were no randomized controlled trials comparing carbon dioxide pneumoperitoneum to any other gas pneumoperitoneum.

AUTHORS' CONCLUSIONS

1. Nitrous oxide pneumoperitoneum during laparoscopic abdominal surgery appears to decrease post-operative pain in patients with low anaesthetic risk.2. Helium pneumoperitoneum decreases the cardiopulmonary changes associated with laparoscopic abdominal surgery. However, this did not translate into any clinical benefit over carbon dioxide pneumoperitoneum in patients with low anaesthetic risk.3. The safety of nitrous oxide and helium pneumoperitoneum has yet to be established. More randomized controlled trials on this topic are needed. Future trials should include more patients with high anaesthetic risk. Furthermore, such trials need to use adequate methods to reduce the risk of bias.

Carbondioxide pneumoperitoneum prevents postoperative adhesion formation in a rat cecal abrasion model

PURPOSE

We aimed to investigate the role of the carbon-dioxide (CO(2)) pneumoperitoneum on the prevention of postoperative adhesion formation.

METHODS

Thirty adult male Sprague-Dawley rats (250-350 g) were used for this study. The rats were randomly divided into three groups; in the sham group (n = 10) only, laparotomy was made, in group 2 (n = 10), a pneumoperitoneum was applied for a half-hour duration, followed by laparatomy, and in group 3 (n = 10), pneumoperitoenum time was 2 hours and after a pneumoperitoneum laparotomy was made. A cecal abrasion model was studied for making an adhesion formation. On day 14, all rats were sacrificed and adhesions were scored. Tissue samples from adhesions and peritonea and the cecum wall were examined, both pathologically and biochemically, for tissue hydroxyproline content.

RESULTS

There was a statistically significant difference between the control and pneumoperitoneum groups, regarding adhesion numbers and grades (P < 0.001). Cecal tissue hydroxypyroline content level was lower in group 1, and statistically significant differences were observed between groups 1, 2, and 3 regarding hydroxyproline content (P < 0.001). There was a statistically significant difference between the control and pneumoperitoneum groups regarding inflammation (P = 0.002).

CONCLUSIONS

Pretreatment with the CO(2) pneumoperitoneum had a prophylactic effect on postoperative adhesion formation in this study.

A prospective randomized, controlled study comparing low pressure versus high pressure pneumoperitoneum during laparoscopic cholecystectomy

BACKGROUND

The increase in intra-abdominal pressure by insufflation of carbon dioxide during laparoscopy brings certain changes in function of organ systems and also leads to postoperative pain. Degree of intra-abdominal pressure is directly related with such change. Laparoscopic cholecystectomy can be performed at low pressure pneumoperitoneum. However, available space for dissection is less than the high pressure pneumoperitoneum.

METHODS

Twenty-six patients for elective laparoscopic cholecystectomy were studied in a prospective, randomized, patient, and surgeon blinded manner. The intra-abdominal pressure was kept either in low pressure (8 mm Hg) or in high pressure (12 mm Hg). All patients underwent two dimensional echocardiography, pulmonary function test and color Doppler examination of lower limb vessels preoperatively and postoperatively. Arterial blood gas analysis and End Tidal CO2 monitored before insufflation, during surgery and after deflation. Pain score was measured by visual analog scale and surgeon's comfort level was recorded. Postoperative analgesia requirement, complications, and hospital stay were recorded. Student t test used for the statistical analysis.

RESULTS

Both groups match for the demographic parameters. Four patients required conversion to high pressure. Intraoperative pO2 level, postoperative pain, analgesic requirement, pulmonary function, and hospital stay were favoring low pressure pneumoperitoneum in a statistically significant manner. There was no difference between 2 groups for duration of surgery, intraoperative, and postoperative complications. However, the technical difficulties were graded more (statistically nonsignificant) with low pressure pneumoperitoneum.

CONCLUSIONS

An uncomplicated gall stone disease can be treated by low pressure laparoscopic cholecystectomy with reasonable safety by an experienced surgeon. Though surgeons experience more difficulty in dissection during low pressure pneumoperitoneum, it is significantly advantageous in terms of postoperative pain, use of analgesics, preservation of pulmonary function, and hospital stay.

Gas embolism during laparoscopic cholecystectomy

Advancements in laparoscopic surgery have resulted in decreased length of hospitalization, reduced postoperative pain, and better cosmesis following general surgical procedures. Carbon dioxide gas embolism is a rare occurrence that can be fatal. We report the case of a patient with a venous gas embolism during laparoscopic cholecystectomy. A 63-year-old woman presented with intermittent right upper quadrant pain, and her abdominal ultrasound showed a possible gallbladder polyp. A laparoscopic cholecystectomy was planned. A Veress needle was placed in the right upper quadrant to initiate abdominal access. Shortly after carbon dioxide insufflation, the patient's hemodynamic status deteriorated, her oxygen saturation dropped, and her end-tidal CO2 decreased. Gas insufflation was immediately stopped, and the patient was resuscitated. She stabilized quickly, and the procedure was performed without further event. She did well postoperatively and was discharged home the next day. Carbon dioxide embolism during laparoscopy, albeit rare, can be a fatal complication of the procedure. Whenever sudden changes in hemodynamic stability occur, venous gas embolism should be considered. As laparoscopic techniques and applications are expanded, the general surgeon must be aware of this entity.

A procedure-specific systematic review and consensus recommendations for postoperative analgesia following laparoscopic cholecystectomy

BACKGROUND

Laparoscopic cholecystectomy has advantages over the open procedure for postoperative pain. However, a systematic review of postoperative pain management in this procedure has not been conducted.

METHODS

A systematic review was conducted according to the guidelines of the Cochrane Collaboration. Randomized studies examining the effect of medical or surgical interventions on linear pain scores in patients undergoing laparoscopic cholecystectomy were included. Qualitative and quantitative analyses were performed. Recommendations for patient care were derived from review of these data, evidence from other relevant procedures, and clinical practice observations collated by the Delphi method among the authors.

RESULTS

Sixty-nine randomized trials were included and 77 reports were excluded. Recommendations are provided for preoperative analgesia, anesthetic and operative techniques, and intraoperative and postoperative analgesia.

CONCLUSIONS

A step-up approach to the management of postoperative pain following laparoscopic cholecystectomy is recommended. This approach has been designed to provide adequate analgesia while minimizing exposure to adverse events.

Low-pressure pneumoperitoneum combined with intraperitoneal saline washout for reduction of pain after laparoscopic cholecystectomy: a prospective randomized study

BACKGROUND

We designed a prospective randomized clinical trial to investigate whether intraperitoneal saline washout combined with a low-pressure pneumoperitoneum (LPSW) was superior to low-pressure pneumoperitoneum (LP) alone as a means of reducing postoperative pain and analgesic consumption in the early recovery period after laparoscopic cholecystectomy (LC).

METHODS

A total of 124 consecutive patients undergoing LC due to uncomplicated symptomatic gallstones were randomized to the LP or LPSW group. In the LPSW group, normal saline at body temperature (25 ml/kg of body weight) was irrigated under the diaphragm. The fluid was evacuated via the passive-flow method through a 16-F closed drain left under the liver for 24 h. We then assessed the intensity of total abdominal postoperative pain using the Visual Analogue Scale (VAS), including the incidence of shoulder-tip pain (STP), total daily analgesia demand rate, analgesic consumption. Quality of life (QOL) within 7 days after the operation was assessed using the Medical Outcomes Study Short Form 36 Health Survey (SF-36). A p value of <0.05 was considered significant.

RESULTS

The mean postoperative pain score was lower by 2.64 +/- 0.86 in the LPSW; the difference equaled 9.64% (p < 0.05). The incidence of STP was lower in the LPSW group (LP 11.29% vs LPSW 1.6%; p = 0.028). The analgesia demand rate was remarkably lower in LPSW vs LP within 24 and 48 h postoperatively (70.96% vs 90.32%; p = 0.006 and 64.51% vs. 83.87%; p = 0.013, respectively). After LPSW vs LP, QOL was better in terms of physical functioning, role limitations due to physical problems, and bodily pain (90.32% vs 77.42%; p = 0.05, 90.32% vs 75.8%; p = 0.03, 91.93% vs 74.19%; p = 0.008, respectively).

CONCLUSION

In terms of lower postoperative pain and a better QOL within the early recovery period, LPSW is superior to LP alone. The saline washout procedure should be recommended during LC because it is a simple way to reduce pain intensity, even after LP operations.

Is CO2 gas unsufflator necessary for laparoscopic training in animals?

OBJECTIVE: To verify the efficacy and safety of compressed air to produce pneumoperitoneum for laparoscopic surgery in pigs for a training program of residence. METHODS: Dalland pigs weighing 15-17kg underwent general anethesia and mechanical ventilation. They were divided in 3 groups: A - (38) the pneumoperitnoneum was established with an automatic CO2 insufflator, B - (7) as in A except the CO2 gas was changed by compressed air, and C - (11) abdomen insufflation was obtained with compressed air directly from hospital pipe network system. Intra-abdominal pressure in all groups was kept between 12 and 15 mmHg. The laparoscopic procedures performed were distributed proportionally among groups: 20 bilateral nephrectomy, 20 dismembered pyeloplasty and 16 partial nephrectomy. Arterial blood sampling for gasometry was obtained before and 2h after establishment of pneumoperitoneum in 5 pigs of group C. RESULTS: The cost of 25 4,5kg CO2 container used in group A was R$ 3,150.00 (U$ 1,050.00). The mean length time of surgeries in groups A, B and C were respectively: 181±30min, 196±39min e 210±47min (p>0.05). Respiratory alkalosis occurred in 3 out of 5 pigs of group C. No animal exhibited signs of gas embolism or died during surgery. CONCLUSION: The use of compressed air for laparoscopy in pigs was safe, reduced costs and did not require the use of an automatic gas insufflator.