Effects Of Carbon Dioxide Pneumoperitoneum Research Articles

Effect of Carbon Dioxide Pneumo-peritoneum in Coagulation Profile of Patients undergoing Laparoscopic Cholecystectomy: A Prospective Cohort Study

Introduction: Laparoscopic Cholecystectomy (LC) is done under general anaesthesia with the patient in a reverse Trendelenburg position and with pressurised carbon dioxide in the peritoneum. This can induce venous stasis in the lower extremities and may affect the balance in the coagulation and fibrinolysis system, thereby thrombo-embolic complications. Aim: To investigate the effects of carbon dioxide pneumoperitoneum on the coagulation system of patients undergoing LC. Materials and Methods: A prospective longitudinal study was carried out from January 2021 to June 2021 among patients aged 18 to 60 years who attended the Surgery Department at Regional Institute of Medical Sciences, Imphal, Manipur, India and were diagnosed with gallstone disease and subsequently underwent LC. Independent variables like age, sex, religion, pre-operative prothrombin time, platelet count, activated Partial Thromboplastin Time (aPTT), and International Normalised Ratio (INR). Outcome variables comprised complications, postoperative prothrombin time, platelet count, aPTT, and INR. Data collected were analysed using Statistical Package for Social Sciences(SPSS) version 21.0. Paired t-tests were employed to test the association between mean values of post-operative and pre-operative PT, aPTT, INR, etc. A p-value of less than 0.05 was considered statistically significant. Results: The study enrolled 71 patients who encountered LC with carbon dioxide pneumo-peritoneum, including 18 male and 54 female patients. Maximum number of patients (28, 38.9%) fell into the 41 to 50 years age group. There was no significant difference in the mean value of prothrombin time (p=0.150) and INR (p=0.437) measured between the pre-operative and postoperative periods. Conclusion: LC is a safe procedure without clinically significant changes in the coagulation profile.

Effects of carbon dioxide pneumoperitoneum on exocrine and endocrine functions, and oxidative state of rat pancreas

ABSTRACT We investigated the effects of increased intra-abdominal pressure during laparoscopy on the endocrine and exocrine functions, oxidative stress and histopathology of the pancreas in rats. We established three experimental groups of eight animals. Group 1 was the untreated control. Forth other two groups, pneumoperitoneum with CO2 was established for 60 min at 6 mm Hg for group 2 and 12 mm Hg for group 3; groups 2 and 3 animals were allowed to re-perfuse for 30 min. Amylase, glucagon and insulin levels were analyzed in blood samples and insulin:glucagon ratio was calculated. Histopathology and malondialdehyde assay were performed on pancreatic tissue samples. Histological damage scores for vasocongestion were increased significantly in groups 2 and 3 compared to group 1. Histological damage scores for inflammatory cell infiltration were increased significantly in group 3 compared to group 1. Malondialdehyde levels were increased significantly in group 3 compared to group 1. We found no significant differences among groups for serum amylase levels or histological damage scores for hemorrhage. Insulin and glucagon levels, and the insulin:glucagon ratio was increased significantly in group 3 compared to groups 1 and 2. We found that in rats routine laparoscopy caused increased serum insulin and glucagon levels, and histopathological changes that indicated ischemia-reperfusion injury to the pancreas.

Pneumoperitoneum in Veterinary Laparoscopy: A Review.

Objective: To review the effects of carbon dioxide pneumoperitoneum during laparoscopy, evaluate alternative techniques to establishing a working space and compare this to current recommendations in veterinary surgery. Study Design: Literature review. Sample Population: 92 peer-reviewed articles. Methods: An electronic database search identified human and veterinary literature on the effects of pneumoperitoneum (carbon dioxide insufflation for laparoscopy) and alternatives with a focus on adaptation to the veterinary field. Results: Laparoscopy is the preferred surgical approach for many human and several veterinary procedures due to the lower morbidity associated with minimally invasive surgery, compared to laparotomy. The establishment of a pneumoperitoneum with a gas most commonly facilitates a working space. Carbon dioxide is the preferred gas for insufflation as it is inert, inexpensive, noncombustible, colorless, excreted by the lungs and highly soluble in water. Detrimental side effects such as acidosis, hypercapnia, reduction in cardiac output, decreased pulmonary compliance, hypothermia and post-operative pain have been associated with a pneumoperitoneum established with CO2 insufflation. As such alternatives have been suggested such as helium, nitrous oxide, warmed and humidified carbon dioxide and gasless laparoscopy. None of these alternatives have found a consistent benefit over standard carbon dioxide insufflation. Conclusions: The physiologic alterations seen with CO2 insufflation at the current recommended intra-abdominal pressures are mild and of transient duration. Clinical Significance: The current recommendations in veterinary laparoscopy for a pneumoperitoneum using carbon dioxide appear to be safe and effective.

An observational study on effect of carbon dioxide pneumoperitoneum on liver function test in laparoscopic cholecystectomy

Background: In many studies it was noticed that following a laparoscopic cholecystectomy (LC), liver function parameters were disturbed. The carbon dioxide pneumoperitoneum causes changes in the splanchnic microcirculation and can affect cardiac, pulmonary, liver and kidney physiology. Alterations in intracranial pressure, blood acid- base control and the immune system have also been seen. This study was done to know the effects of carbon dioxide pneumoperitoneum on liver function tests in LC. Aim of the study was to study the significance of alterations in Liver function tests and procedure’s safetyMethods: Blood samples of 100 patients who underwent laparoscopic cholecystectomy preoperatively once and post operatively after 24 hours were collected. These blood samples were tested for LFT. The pre op and post op levels of these liver function test values were compared.Results: The level of serum AST, ALT, bilirubin (total) and ALP were increased significantly during the first 24 hrs. Postoperatively after laparoscopic cholecystectomy as compared to baseline values and the levels of serum albumin and total proteins were decreased.Conclusions: There may be a transient elevation of hepatic enzymes after LC and the major causative factor seemed to be CO2 pneumoperitoneum.

English

BACKGROUND: Laparoscopic cholecystectomy is a common surgical procedure and carbon dioxide pneumoperitoneum created for this purpose may alter the coagulation profile of these patients. This study aims to find the effects of carbon dioxide pneumoperitoneum on coagulation profile and assess if there is an increased risk of thrombosis. MATERIALS AND METHODS: A clinical observational study was conducted with 50 patients who underwent laparoscopic cholecystectomy using carbon di oxide pneumoperitoneum. The prothrombin time and D-dimer values were calculated before and after surgery .using the paired t test data was analyzed. RESULTS: The study showed a decrease in the prothrombin time and increase in the D-dimer value post operatively. The mean of prothrombin time after surgery was 0.13 seconds lower than the preoperative value and D-dimer was found to be elevated three times the pre operative values. The p value calculated for both were highly significant. CONCLUSION: Laparoscopic cholecystectomy using carbon dioxide pneumoperitoneum leads to hypercoagulable states. Hence stringent measures need to be taken to put the patient on prophylaxis for deep vein thrombosis to avoid dire consequences.

Effects of carbon dioxide pneumoperitoneum on postoperative adhesion formation and oxidative stress in a rat cecal abrasion model

IntroductionIt is claimed that CO2 pneumoperitoneum (CP) is less adhesiogenic than laparotomy. Our aim in this study was to investigate the local oxidative stress responses and related adhesion formation resulting from exposure to CP. MethodsForty-five rats were randomised into six groups. Group 1 underwent laparotomy only; in group 2, 6 mmHg CP was performed for 60 min; in group 3, the same procedure was carried out using 12 mmHg CP; in group 4, laparotomy and cecal-peritoneal abrasion were performed; in group 5, 6 mmHg CP was performed for 60 min, followed by laparotomy and cecal-peritoneal abrasion; in group 6, the same procedure was carried out using 12 mmHg CP. Groups 1, 2 and 3 were sacrificed immediately and used only for biochemical examination. The other groups were sacrificed on the 14th postoperative day. ResultsThe total adhesion scores, thickness, quantity, extent and type of adhesions decreased steadily in groups 4, 5 and 6 (p < 0.05). The median values for neutrophil and monocyte infiltration, and for capillary and fibroblast proliferation decreased steadily in groups 4, 5 and 6 (p < 0.05). CAT, SOD and GSHPx levels decreased significantly in line with increasing pressure in groups 1, 2 and 3. SOD and GSHPx levels were similar in groups 4, 5 and 6, while CAT levels decreased with increasing pressure in groups 4, 5 and 6. ConclusionIt was found that CP is associated with less adhesion formation than laparotomy in the presence of similar antioxidant levels. The reduced adhesion formation is probably caused by a decreased inflammatory response.

Effects of carbon dioxide pneumoperitoneum on the cerebral blood flow during gynecological laparoscopic tumor resection

Objective To observe the effects of carbon dioxide pneumoperitoneum on the cerebral blood flow of the patient which undergoing gynecological laparoscopic tumor resection.Methods 40 ASA Ⅰ-Ⅱ patients with gynecologic tumor undergoing laparoscopic surgery without known cerebral or cardiovascular system disease were selected.PaO2,PaCO2,SaO2,PjvO2,SjvO2 values were recorded before and 20 ain after the instrfllation in the trendelenburg position.Results Before pneumoperitoneum,the SjvO2,CjvO2,PaCO2 was(66±7)％,(9.4±1.6)％ and (4.2±0.4) kPa respectively.And after insufflation,the SjvO2,CjvO2,PaCO2 was (84±6)％,(11.6±1.8)％ and (5.3±0.4) kPa respectively.PaCO2 increased obviously (P＜0.01).Ca-jvDO2 was decreased significantly before and after insufflation,whichwas (5.1±1.2)％ vs (2.4±0.9)％ (P＜0.01).Conclusions The CO2 pneumoperitoneum has obvious effect on the change of the cerebral blood circulation during the operation of gynecology laparoscopy,cerebral blood flow increased remarkably and Ca-jvDO2 decreased significantly.This kind of change implied anoxia of brain. Key words: Gynecology Laparoscopy ; CO2 pneumoperitoneum ; Cerebral blood flow ;

Evaluation of the effects of carbon dioxide pneumoperitoneum on abdominal wall wound healing in rats undergoing segmental resection and anastomosis of the left colon

To evaluate the influence of carbon dioxide pneumoperitoneum on abdominal wall wound healing in rats. Eighty rats underwent laparotomy, segmental left colon resection, and anastomosis. The animals were divided into three experimental groups and one control group: EI = pneumoperitoneum for 30 minutes before laparotomy (n=20); EII = pneumoperitoneum for 30 minutes after abdominal closure (n=20); EIII = pneumoperitoneum for 30 minutes before laparotomy and 30 minutes after abdominal closure (n=20); C = control group, without pneumoperitoneum (n=20). In each group, 10 animals were killed 7 days and 10 animals 14 days postoperatively. A segment of the abdominal wall was resected and subjected to tensile strength testing. Another segment of abdominal muscle was used for histopathological analysis; the specimens were fixed in formalin and stained with hematoxylin and eosin. There were no differences in histopathology and tensile strength values among animals in the experimental and control groups 7 or 14 days after surgery. Under the present experimental conditions, carbon dioxide pneumoperitoneum did not interfere with abdominal wall wound healing.

Effects of carbon dioxide pneumoperitoneum on hepatic and renal morphology of rats after segmental colectomy and colonic anastomosis

To evaluate the effects of increased intraperitoneal pressure caused by carbon dioxide pneumoperitoneum on the hepatic and renal morphology of rats. Fifty-four adult male rats were randomly divided into three groups (P, PP and C) after anesthesia: P - in 18 animals, pneumoperitoneum was established for 30 minutes immediately before laparotomy; PP - in 18 animals, pneumoperitoneum was established for 60 minutes divided into 30 immediately before laparotomy and 30 after abdominal closure; control group (C) - 18 animals underwent laparotomy without pneumoperitoneum induction. The pneumoperitoneum was maintained at a pressure of 5 mm Hg. Nine animals in each group were killed on the 3(rd) and 7(th) postoperative days, when kidney and liver samples were collected for morphological analysis. The liver specimens were stained with hematoxylin and eosin (HE), and the kidney specimens, with HE and von Kossa. Blinded examiners analyzed the slides. No changes in renal morphology were found. Liver samples showed histological signs of degeneration in animals in the pneumoperitoneum groups killed on the 7(th) postoperative day (p=0.029). The CO(2) pneumoperitoneum did not affect renal morphology but caused hydropic degeneration in the liver of animals killed on the 7(th) postoperative day.

Effect of Pressure- Versus Volume-Controlled Ventilation on the Ventilatory and Hemodynamic Parameters During Laparoscopic Appendectomy in Children: A Prospective, Randomized Study

Several ventilatory strategies have been introduced to minimize the respiratory and hemodynamic effects of carbon dioxide pneumoperitoneum during laparoscopic surgery. The purpose of this study was to compare the effects of pressure-controlled ventilation (PCV) with that of volume-controlled ventilation (VCV) on the ventilatory and hemodynamic parameters in children undergoing laparoscopic appendectomy. Thirty-four children undergoing laparoscopic appendectomy were randomly allocated to receive mechanical ventilation using either VCV (n=17) or PCV (n=17) mode. Positive end-expiratory pressure (PEEP) 5 cm H(2)O was applied to all patients. Hemodynamic and ventilatory parameters were measured 10 minutes before pneumoperitoneum (T1) and 30 minutes after pneumoperitoneum (T2). Peak and mean airway pressures were significantly increased at T2 from T1 in both groups. Mean airway pressure was significantly higher in the PCV group compared with that in the VCV group. Dynamic compliance was significantly higher in the PCV group than in the VCV group at T2, although it was decreased at T2 from T1 in both groups. Mean blood pressure was significantly increased at T2 from T1 in both groups without intergroup difference. During the study period, SpO(2) remained constant without intergroup or within-group differences. During laparoscopy, mean airway pressure and dynamic compliance were significantly higher during PCV with 5 cm H(2)O PEEP compared with that in VCV with 5 cm H(2)O PEEP. And, as there were no differences in other ventilatory parameters and oxygen saturation, both VCV and PCV can be used safely in children undergoing laparoscopic surgery.

Effect of Pneumoperitoneum on Renal Tissue Oxygenation and Blood Flow in a Rat Model

To determine the correlation between the renal blood flow (RBF) and tissue oxygenation (PO(2)) at varying intra-abdominal pressures (IAPs) and to compare the effects on renal blood flow from carbon dioxide-induced pneumoperitoneum. Carbon dioxide pneumoperitoneum was established in Sprague-Dawley rats (n = 6). Licox oxygen/temperature tissue probes were laparoscopically inserted into the renal parenchyma, with the renal PO(2) and RBF recorded every 30 seconds while the IAP was gradually increased. Microprobes measuring the RBF, mean arterial pressures and serum pH were placed into the parenchyma to compare the effects of carbon dioxide pneumoperitoneum (n = 7) with that of open surgery (n = 6) and medical air pneumoperitoneum (n = 6). Renal PO(2) was inversely related to the IAP (P < .001). Despite the reduction in IAP, the renal PO(2) in the recovery phase was lower than at baseline (P = .045). The renal PO(2) and RBF changed in a virtually identical pattern at varying levels of IAP (P > .05). The RBF significantly declined with a pneumoperitoneal pressure of 15 and 20 mm Hg (P = .022), regardless of the gas used to create the pneumoperitoneum. A partial reversal of the RBF occurred with a decrease of the IAP. The RBF in the open surgical arm remained unchanged. Although both the serum pH and the mean arterial pressure were inversely proportional to the IAP (P < .001), the mean arterial pressure was depressed to the greatest extent in the medical air group (P = .02). These results have demonstrated that elevated IAP secondary to pneumoperitoneum causes significant renal hypoxia and decreased RBF. Additionally, this experiment has demonstrated the use of the Licox probes in monitoring the renal PO(2) and established a novel method for evaluating the effects of IAP on the kidney.

Effects of carbon dioxide pneumoperitoneum on hepatic function in obstructive jaundice: an experimental study in a rat model

The physiology of the patient during laparoscopy differs from that of open surgery. Both pneumoperitoneum and obstructive jaundice impair the hepatic function, but the combined insult has not been previously examined. In this study, we aimed to investigate the effects of carbon dioxide (CO(2)) pneumoperitoneum on hepatic function in a rat model of obstructive jaundice. Forty-four male Sprague-Dawley rats were divided into four groups: group 1 (n = 10), sham-operated group; group 2 (n = 12), obstructive jaundice group; group 3 (n = 10), CO(2) pneumoperitoneum group; and group 4 (n = 12), obstructive jaundice and CO(2) pneumoperitoneum group. Common bile duct was ligated and divided in the obstructive jaundice groups. After 6 days, a 12-mmHg pneumoperitoneum was induced, maintained for 60 min, and released for 120 min. Blood samples were drawn for the measurement of white blood cell and platelet counts, serum liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], total bilirubin). Tissue samples were obtained for analyses of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels. We evaluated the degree of liver injury on a grading scale from 0 to 4, histopathologically. Pneumoperitoneum after biliary obstruction resulted in an increase in AST and ALT levels and a decrease in white blood cell and platelet counts. However, changes in liver tissue MDA, GSH, and SOD levels did not correlate with the changes in AST and ALT levels and white blood cell and platelet counts. After sham operation with pneumoperitoneum, the GSH levels in liver homogenate were significantly decreased in the group 3 when compared to the group 2. On the other hand, obstructive jaundice itself caused significant reduction in the SOD activity of liver homogenate in comparison to the group 3. Histopathologically, sinusoidal congestion and vacuolization were more severe in the group 3. Alterations in hepatic function occur in pneumoperitoneum applied jaundiced subjects. However, there were no statistically significant differences between the groups 2 and 4 with regard to white blood cell and platelet counts, serum liver enzymes including AST, ALT, and total bilirubin values, MDA and GSH levels and SOD activity of liver homogenate, and histologic damage. These results indicate that there is no additional risk on liver function associated with pneumoperitoneum performed in obstructive jaundice.

The effects of carbon dioxide pneumoperitoneum on ovarian blood flow, oxidative stress markers, and morphology during laparoscopy: a rabbit model

To determine the effect of CO(2) pneumoperitoneum on the ovaries in an experimental pneumoperitoneum model. Experimental controlled study. University hospital. Sixteen adult female conventional rabbits. Group I (8 rabbits) was not subjected to intra-abdominal pressure (IAP). In group II (8 rabbits), IAP insufflation was performed at 12 mm Hg. In total, 60 minutes of pneumoperitoneum and 10 minutes of reperfusion were maintained. Ovarian blood flow (OBF) was studied using laser Doppler flowmetry. The time points of OBF measurements were as follows: OBFbaseline, 10 minutes before insufflation; OBF30min, 30 minutes after pneumoperitoneum; OBF60min, 60 minutes after pneumoperitoneum; and OBFreperfusion, 10 minutes after pneumoperitoneum desufflation. Mean OBF changes during CO(2) pneumoperitoneum (OBFmean) were also assessed. Blood perfusion units, tissue malondialdehyde values, and histopathologic damage scores. In group II, mean OBF values were significantly lower than in group I, especially for OBF30min, OBF60min, OBFreperfusion, and OBFmean. The mean tissue malondialdehyde value for group II was significantly higher than in the control group (104.48 +/- 20.07 nmol/g vs. 64.12 +/- 8.77 nmol/g, respectively). Compared with group I, in group II histologic specimens of the ovaries had higher scores for follicular cell degeneration, vascular congestion, hemorrhage, and inflammatory cell infiltration. Pneumoperitoneum, even at normal IAP levels, leads to significant oxidative stress-induced biochemical and histologic damage to the ovaries.

Effects of Carbon Dioxide Insufflation and Body Position on Blood Gas Values in Horses Anesthetized for Laparoscopy

The objective of the study was to describe the effects of carbon dioxide pneumoperitoneum and Trendelenburg position on arterial blood gas values in horses anesthetized for laparoscopy. The study design was a prospective case series using 14 healthy adult horses anesthetized for elective laparoscopic surgery. All horses in the study were maintained under anesthesia with halothane in oxygen with intermittent positive-pressure ventilation. A pneumoperitoneum of 15 mmHg or less was achieved with carbon dioxide, and horses were tilted to a 35-degree Trendelenburg position to allow the completion of laparoscopic cryptorchidectomy (n = 13) or ovariectomy (n = 1). Heart rate, mean arterial pressure, and arterial blood gases were recorded at six time intervals throughout the procedure. Results of the study indicated a pH that decreased and partial pressure of carbon dioxide (PaCO 2) and mean arterial pressure that increased over time and differed significantly from baseline during Trendelenburg position. Partial pressure of oxygen (PaO 2) was significantly lower than baseline after assumption of Trendelenburg position and did not improve on return to normal recumbency and abdominal pressure. As body weight increased, pH and PaO 2 decreased and PaCO 2 increased. We concluded that horses placed in Trendelenburg position have changes that are transient, with the exception of PaO 2. Heavier horses have a greater change in pH, PaCO 2, and PaO 2 than lighter horses during abdominal insufflation and Trendelenburg position. The changes incurred during CO 2 abdominal insufflation and Trendelenburg position are transient, with the exception of a decreased PaO 2. Heavy horses undergoing abdominal insufflation and Trendelenburg position should be closely monitored for critical cardiopulmonary values.

Much Remains to Be Learned

Approximately 15 years of experience and tens of thousands of cases have led to a strong knowledge base for advanced laparoscopy. Additionally, decades of gynecologic laparoscopy led to a large experience with patients who underwent diagnostic or relatively straightforward therapeutic procedures. Our experience with and understanding of the effects of carbon dioxide pneumoperitoneum are far from nascent. Nonetheless, a report in this issue of the Journal provides evidence that although pneumoperitoneum appears to be well-tolerated by most patients, significant sequelae and complications can occur in ways not previously recognized.

Effect of carbon dioxide pneumoperitoneum and wound closure technique on port site tumor implantation in a rat model

The purpose of this study was to evaluate the effects of carbon dioxide (CO2) pneumoperitoneum and wound closure technique on port site tumor implantation. A standard quantity of rat mammary adenocarcinoma (SMT2A)was allowed to grow in a flank incision in Wistar-Furth rats (n = 90) for 14 days. Thereafter, 1-cm incisions were made in each animal in three quadrants. There were six control animals. The experimental animals were divided into a 60-min CO2 pneumoperitoneum group (n = 42) and a no pneumoperitoneum (n = 42) group. The flank tumor was lacerated transabdominally in the experimental groups. The three wound sites were randomized to closure of (a) skin; (b) skin and fascia; and (c) skin, fascia, and peritoneum. The abdominal wounds were harvested en bloc on postoperative day 7. Histologic comparison of the port sites in the pneumoperitoneum and no-pneumoperitoneum groups did not demonstrate a statistically significant difference in tumor implantation for any of the closure methods. Evaluation of the closure techniques showed no statistical difference between the pneumoperitoneum group and the no-pneumoperitoneum group in the incidence of port site tumor implantation. Within the no-pneumoperitoneum group, there was a significant increase (p = 0.03) in tumor implantation with skin closure alone vs all three layers. Additionally, when we compared all groups by closure technique, the rate of tumor implantation was found to be significantly higher (p = 0.01) for skin closure alone vs closure of all three layers. This study suggests that closure technique may influence the rate of port site tumor implantation. The use of a CO2 pneumoperitoneum did not alter the incidence of port site tumor implantation at 7 days postoperatively.

Renal hemodynamics during carbon dioxide pneumoperitoneum: an experimental study in pigs.

Laparoscopic living donor nephrectomy is increasingly being performed, although the effects of carbon dioxide pneumoperitoneum (CO2 PP) on renal function and hemodynamics and the levels of vasopressin are not well studied. Renal blood flow, renal venous pressure, urine output, and vasopressin concentrations in renal venous blood were measured in pigs subjected to 12 mmHg of CO2 PP for 150 min. Renal blood flow was decreased at induction of PP and increased during the first 30 min after exsufflation. Renal venous pressure was increased during PP. There was indirect evidence of a decrease in urine output during PP. No changes in renal venous vasopressin concentrations were seen. A CO2 PP of 12 mmHg causes changes in renal hemodynamics and urine output. No changes in vasopressin levels were seen in this pig model, suggesting that other explanations for the observed changes must be sought.

Effects of carbon dioxide pneumoperitoneum on hemodynamics in cirrhotic rats.

The aim of our study was to investigate the effect of carbon dioxide pneumoperitoneum on systemic and splanchnic hemodynamics in cirrhotic rats. Sprague-Dawley rats (n = 80) were used in this study. Liver cirrhosis was induced by thioacetamide administration intraperitoneally (200 mg/kg body weight, twice a week for 16 weeks). The radioactive microsphere method was used to measure systemic and regional hemodynamic parameters before, 1 h after the start, and 1 h after the release of pneumoperitoneum. Splanchnic blood flow and cardiac index were significantly depressed during pneumoperitoneum in liver cirrhosis and control groups, but no significant differences were seen between the two groups. In both groups, portal venous inflow decreased and hepatic arterial blood flow increased significantly during pneumoperitoneum. However, during pneumoperitoneum, total hepatic blood flow as a percentage of its value before pneumoperitoneum was lower in cirrhotic rats (71.0%) than in control rats (91.9%) (p <0.05, Mann-Whitney U-test). Carbon dioxide pneumoperitoneum markedly decreases total hepatic blood flow in cirrhotic rats due to the impaired hepatic arterial buffer response. Liver function should be carefully controlled in cirrhotic patients after laparoscopic surgery with pneumoperitoneum.

Anaesthesia, minimally invasive surgery and pregnancy

Minimally invasive surgery is being performed more frequently in pregnant patients. Numerous published reports have documented the safety and advantages of laparoscopic cholecystectomy and laparoscopic appendectomy during pregnancy. Pregnancy is associated with a variety of changes in the respiratory and cardiovascular systems, which make the parturient undergoing laparoscopic surgery particularly susceptible to hypoxia, hypercarbia and hypotension. This chapter provides a review of those physiological changes of pregnancy of particular concern for anaesthesiologists, and of the physiological responses to intra-abdominal carbon dioxide insufflation, not only in healthy patients, but also in the altered physiological state associated with pregnancy. We also describe our approach to anaesthetic management for minimally invasive surgery during pregnancy. With appropriate precautions, including vigilant monitoring and anticipation and treatment of the potential adverse effects of carbon dioxide pneumoperitoneum, anaesthesiologists may provide safe care for these patients, and pregnant women can benefit from the advantages of minimally invasive surgery.

Randomized Comparison of Conventional Carbon Dioxide Insufflation and Abdominal Wall Lifting for Laparoscopic Cholecystectomy

Gasless laparoscopy using abdominal wall lifting (AWL) has been developed in an attempt to avoid the adverse effects of carbon dioxide pneumoperitoneum that may occur in conventional laparoscopy. However, lifting has been criticized for its poor operative space and surgical invasiveness. This study compared the AWL method with conventional CO2 pneumoperitoneum for laparoscopic cholecystectomy with respect to operation performance, postoperative course, and stress response. During a 6-month period, 95 patients with symptomatic gallstones were randomly assigned to receive laparoscopic cholecystectomy with conventional CO2 pneumoperitoneum (CO2 group; N = 47) or the AWL method (AWL group; N = 48). Operative results and operative time were recorded. Cardiopulmonary functions were assessed, and arterial blood gases were analyzed during surgery. Urinary cortisol, vanillylmandelic acid, metanephrines, and nitrogen loss; serum complement 3, C-reactive protein, and interleukin-6; postoperative pain; and the presence of nausea and vomiting were assessed for 48 hours after surgery. Postoperative time to recovery of flatus, tolerance of a full oral diet, and full activity were also determined. Only three significant differences were found. First, intraoperative ventilatory function deteriorated significantly less in the AWL group. Second, arterial blood gas determinations and capnography showed a greater decrease in intraoperative arterial pH and compliance with CO2 retention and an increase in peak airway pressure in the CO2 group (P < 0.05), reflecting poorer ventilatory performance. Third, preparation time and total operating time were significantly greater with the AWL method (P < 0.05). Although AWL required a longer operation time, our results suggest that the technique may still have value in high-risk patients with cardiorespiratory diseases.