Studies related to CO2

Experimetal and clinical consequences of using carbon dioxide

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

Guven SMuci EUnsal MAYulug EAlver ADuman MKMentese A.



Department of Obstetrics and Gynecology, Karadeniz Technical University, School of Medicine, Trabzon, Turkey. 

OBJECTIVE: To determine the effect of CO(2) pneumoperitoneum on the ovaries in an experimental pneumoperitoneum model. DESIGN: Experimental controlled study. SETTING: University hospital. PATIENT(S): Sixteen adult female conventional rabbits. INTERVENTION(S): 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. MAIN OUTCOME MEASURE(S): Blood perfusion units, tissue malondialdehyde values, and histopathologic damage scores. RESULT(S): 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. CONCLUSION(S): Pneumoperitoneum, even at normal IAP levels, leads to significant oxidative stress-induced biochemical and histologic damage to the ovaries.


Fertil Steril. 2008 Dec 8. [Epub ahead of print] 


The hemodynamic effects of CO2-induced pressure on the kidney in an isolated perfused rat kidney model.


Khoury WSzold AKlausner JMWeinbroum AA.


Division of General Surgery B, Tel Aviv Sourasky Medical Center, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.


BACKGROUND: Variable mechanisms were suggested to mediate the changes in renal hemodynamics during pneumoperitoneum. To assess whether it can be pressure dependent only, we conduct a study in an isolated, pressurized, and perfused organ model. METHODS: Seventy Wistar rat kidneys were perfused with oxygenated, 3% albumin-contained Krebs-Henseleit solution. Experiments took place within Plexiglass chamber that provided conditions for perfusion of organs, humidity, and maintenance of intracameral CO2 pressures [0 (control), 3, 5, 8, 12, 15, and 18 mm Hg]. All kidneys (10/group) were perfused for 60 minutes. One-half of the groups were perfused for an additional 30 minutes, during which the perfusion pressures were reduced to 0 mm Hg. pH of the perfusate was measured as well. RESULTS: The perfusion pressure increased and the kidney flow decreased slightly, in proportion with the intrachamber pressure. Urine output decreased to a minimum of 40% in >or=8 mm Hg pressure conditions, compared with the control group. The pH values were below normal, during experimental pneumoperitoneum. CONCLUSIONS: Pneumoperitoneal conditions are a direct cause of changes in renal urinary output. The increase in pCO2 pressure and consequently low intraorgan pH may contribute to a mild transient renal damage during pneumoperitoneum.


Surg Laparosc Endosc Percutan Tech. 2008 Dec;18(6):573-8



The effect of intra-abdominal pressure on the generation of 8-iso prostaglandin F(2alpha) during laparoscopy in rabbits.


De Souza AM, Wang CC, Chu CY, Lam PM, Rogers MS.


Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR.


BACKGROUND: Carbon dioxide pneumoperitoneum induces peritoneal oxidative stress. The aim of this study was to verify the effect of intra-abdominal pressure on oxidative stress in the peritoneum and on post-operative adhesion formation. METHODS: Forty-one rabbits underwent laparoscopic surgery: either gasless, or with CO2-pneumoperitoneum at pressures of 5, 10 or 15 mmHg. Serial parietal peritoneal biopsies were taken at various time-points: immediately after reaching the abdominal cavity, 30, 60, 90 and 120 min afterwards, and 15 min after abdominal desufflation. 8-iso prostaglandin F(2alpha) (8-iso PGF(2alpha)), a marker of oxidative stresss, was assayed by enzyme immunoassay and adhesion formation was scored by second-look laparoscopy on day 14. RESULTS: The gasless group showed no significant changes in 8-iso PGF(2alpha). Conversely, significant changes occurred in CO2-pneumoperitoneum in a time- and pressure-dependent manner. Adhesions developed only in the CO2-pneumoperitoneum groups, and total adhesion score was correlated with the amount of CO2 insufflated and intra-abdominal pressure, but not with 8-iso PGF(2alpha), which was correlated with intra-abdominal pressure. CONCLUSION: Intra-abdominal pressure increased 8-iso PGF(2alpha) in the parietal peritoneum in a graded fashion, whilst gasless laparoscopy had no impact. It also influenced the frequency and severity of adhesion formation, but no causal link was found between 8-iso PGF(2alpha) and post-operative adhesion formation.


Hum Reprod. 2003 Oct;18(10):2181-8 



CO2 promotes plasminogen activator inhibitor type 1 expression in human mesothelial cells.


Bergstrom M, Falk P, Holmdahl L.


Department of Surgery, Sahlgrenska University Hospital/Ostra, Goteborg University, SE-41685 Goteborg, Sweden.


Background: Previous observations have indicated that CCO2 insufflation increases peritoneal plasminogen activator inhibitor type 1 (PAI-1) expression. Methods: Primarily cultured human peritoneal mesothelial cells were exposed to either flowing or pressurized CO2 for 90 min. Unexposed cultures served as controls. Samples of cell culture media were taken at 0, 5, and 24 h after exposure to measure media pH, PAI-1, and tissue-type plasminogen activator (t-PA) protein release. Simultaneous samples were taken to measure PAI-1 and t-PA mRNA expression. Results: Mesothelial cells exposed to flowing CO2 released more PAI-1 than those exposed to pressurized CO2 (p <0.001) and controls (p <0.001). Cells exposed to flowing CO2 had an increased PAI-1 mRNA expression at 5 h. Conclusions: CO2 increased mesothelial cell PAI-1 expression involving a transcriptional mechanism. These findings might provide a mechanism for adhesion formation and cancer progression following laparoscopic surgery.


Surg Endosc. 2003 Jun 17 



Adhesion formation in intubated rabbits increases with high insufflation pressure during endoscopic surgery. 


Yesildaglar N; Koninckx PR


The aim of the study was to test the hypothesis that the increase in adhesion formation by CO2 pneumoperitoneum is caused by mesothelial hypoxaemia. Therefore the effect of the intra-abdominal pressure together with the flow rate upon adhesion formation was evaluated in rabbits following laser and bipolar lesions during endoscopic surgery using humidified CO2 at 35 +/- 1 degrees C. The intra-abdominal pressure and flow rate were 5 mmHg and 1 l/min in group 1 (n = 5), 5 mmHg and 10 l/min in group 2 (n = 4), 20 mmHg and 1 l/min in group 3 (n = 5) and 20 mmHg and 10 l/min in group 4 (n = 4) respectively. A rapid and reliable intubation method for rabbits was developed to permit high insufflation pressure. By two-way analysis of variance, total adhesion scores following a laser lesion increased with flow rate (P = 0.0003) and insufflation pressure (P = 0.002). Total adhesion scores of bipolar lesions increased with pressure (P = 0.02) but not with flow rate (P = 0.1). The total adhesion scores of laser and bipolar lesions together increased with flow rate (P = 0.005) and with insufflation pressure (P = 0.004). There was no statistical interaction between flow rate and insufflation pressure. In conclusion, the insufflation pressure in endoscopic surgery with COpneumoperitoneum is a co-factor in adhesion formation, together with desiccation.


Hum Reprod – 01-MAR-2000; 15(3): 687-91



Hypoxaemia induced by CO2 or helium pneumoperitoneum is a co-factor in adhesion formation in rabbits.


Molinas CR; Koninckx PR


A prospective randomized trial in a rabbit model was performed to test the hypothesis that the increase in adhesion formation following prolonged pneumoperitoneum is mediated by peritoneal hypoxaemia. Laparoscopic standardized opposing lesions were performed in uterine horns and pelvic sidewalls by bipolar coagulation and CO2 laser in six groups of eight animals. Pure CO2 or helium pneumoperitoneum was used for 10 (groups I and IV) or 45 min (groups II and V) to confirm the effect of duration of pneumoperitoneum and 96% of CO2 or helium with 4% of oxygen (group III and VI) for 45 min to assess the effect of the addition of oxygen. After 7 days, adhesion formation was scored by laparoscopy. By two-way analysis of variance, total, extent, type and tenacity of adhesion scores increased (P = 0.0003, P = 0.0004, P = 0.0004 and P = 0.004) with increasing duration of pneumoperitoneum and decreased (P = 0.02, P = 0.03, P = 0.01 and P = 0.05) with the addition of oxygen. No differences were found between CO2 and helium. In conclusion these data confirm the effect of pneumoperitoneum upon adhesions and demonstrate its reduction by oxygen, strongly suggesting that the main cause of adhesion formation is the relatively superficial hypoxaemia produced by the pneumoperitoneum.


Hum Reprod – 01-AUG-2000; 15(8): 1758-63



Peritoneal response to pneumoperitoneum and laparoscopic surgery.


Bergström M; Ivarsson ML; Holmdahl L


BACKGROUND: It is generally believed that laparoscopic surgery inflicts less trauma to the peritoneum than open surgery. Local peritoneal fibrinolysis is a critical factor in adhesion development. The objective was to investigate fibrinolytic changes in the peritoneum during laparoscopic and open surgery. METHODS: At laparotomy (n = 10) peritoneal biopsies were taken at opening of the abdomen and just before closure. At laparoscopy (n = 12) opening peritoneal biopsies were taken after carbon dioxide insufflation, and closure biopsies just before exsufflation. Tissue concentrations of tissue-type plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1) and the resulting tPA activity were assayed. RESULTS: Concentrations of tPA in peritoneal tissue declined during operation in both groups, but significantly so only in the laparotomy group (- 53 per cent; P = 0.01). PAI-1 levels were higher in opening biopsies from the laparoscopy group (P = 0.004). There was an increase in PAI-1 concentration during laparotomy, but not during laparoscopy. At the end of the operation, there was no difference between the groups. The resulting tPA activity did not differ between groups at opening or closure. In both groups there was a significant decline during operation (laparotomy: – 59 per cent, P = 0.02; laparoscopy: – 63 per cent, P = 0.01). CONCLUSION: These findings indicate that the peritoneal response to open and laparoscopic surgery is similar. The initial rise in peritoneal PAI-1 concentration during laparoscopy suggests an adverse effect of carbon dioxide insufflation, which might affect peritoneal repair.


Br J Surg – 01-NOV-2002; 89(11): 1465-9



Role of the plasminogen system in basal adhesion formation and carbon dioxide pneumoperitoneum-enhanced adhesion formation after laparoscopic surgery in transgenic mice.


Molinas CR; Elkelani O; Campo R; Luttun A; Carmeliet P; Koninckx PR


To evaluate the role of plasminogen activator inhibitor-1 (PAI-1), urokinase plasminogen activator (uPA), and tissue-type plasminogen activator (tPA) in adhesion formation after laparoscopic surgery.Prospective, randomized study.Academic research center.Seventy female wild-type and transgenic knockout mice for PAI-1 (PAI-1(-/-)), uPA (uPA(-/-)) or tPA (tPA(-/-)).Standardized lesions to induce peritoneal adhesions were performed during laparoscopy. To evaluate basal adhesions and pneumoperitoneum-enhanced adhesions, the pneumoperitoneum was maintained for 10 minutes or 60 minutes, respectively. Peritoneal biopsy samples were obtained during and after 60 minutes of carbon dioxide pneumoperitoneum.Adhesions were blindly scored after 7 days. Concentrations of PAI-1 and tPA were measured by using enzyme-linked immunosorbent assay.In PAI-1, uPA, and tPA wild-type mice, pneumoperitoneum enhanced adhesions. Compared with wild-type mice, basal adhesions were fewer in PAI-1(-/-) mice and more in uPA(-/-) and tPA(-/-) mice. Pneumoperitoneum did not enhance adhesions in these transgenic mice. PAI-1 concentration increased after 60 minutes of pneumoperitoneum whereas tPA concentration did not change.Impaired fibrinolysis increases basal adhesions. The absence of pneumoperitoneum-enhanced adhesions in PAI-1(-/-), uPA(-/-), and tPA(-/-) mice and the increase in PAI-1 expression indicate that PAI-1 up-regulation by carbon dioxide pneumoperitoneum is a mechanism of pneumoperitoneum-enhanced adhesion formation.


Fertil Steril – 01-JUL-2003; 80(1): 184-92



The impact of gas laparoscopy on abdominal plasminogen activator activity.


Nagelschmidt M; Gerbecks D; Minor T


BACKGROUND: The impairment of intestinal perfusion following induction of a pneumoperitoneum may lead to a reduction of peritoneal tissue plasminogen activator (tPA) activity and a concomitant increased risk of adhesion formation. METHODS: Pigs were laparotomized to take peritoneal biopsy specimens from the cecum, the ileum, and the abdominal wall. A 15 mmHg pneumoperitoneum was established for 3 h by the insufflation of carbon dioxide (group 2, n = 6) or helium (group 3, n = 6). Group 1 (n = 7) received no gas insufflation. After a 2-h recovery period, additional tissue samples were harvested. Specific tPA activity was then determined in the tissue extracts. RESULTS: During surgery, specific tPA activity decreased in all the samples. As compared with the control group (100%), this reduction was strongly aggravated in the cecum (-67.6%, p < 0.05) and the ileum (-70.8%) of the CO2 group but only slightly aggravated in the helium group. The parietal peritoneum was not specifically affected by gas insufflation. Conclusion: The use of a pneumoperitoneum with carbon dioxide significantly affects peritoneal tPA activity and thus may represent a stimulus for adhesion formation.

Surg Endosc – 01-JUN-2001; 15(6): 585-8



De novo adhesions due to dry laparoscopy gas


R. Turner, D.Ott


The risk of adhesion formation at laparoscopy is dependent on circumstances that contribute to or minimize the likelihood of adhesion formation, just as it is during laparotomy. It has long been noted that one of the factors that causes peritoneal adhesion formation is tissue desiccation. The finding in this study of fewer adhesions with extraperitoneal surgery and more with intraperitoneal surgery validates this principle. The gas used to create a pneumoperitoneum has 0.0002% relative humidity and is delivered through trocars restricted with instruments creating a forceful jet streaming effect. This causes dramatic peritoneal cell vapor pressure changes resulting in rapid surface drying of the peritoneum and an increase in solute concentration and in peritoneal fluid viscosity. The "cold dry" gas alters peritoneal cell integrity and increases peritoneal cell trauma and death that can lead to adhesion formation. The maintenance of a normal physiologic intra-abdominal environment during laparoscopic surgery by heating and humidification ("warm and wet"), such as has been proven using the Insuflow (LEXION Medical, St Paul, Minn) device, reduces or eliminates cell desiccation, maintains peritoneal fluid integrity, allows for increased peritoneal cell survival, and improves clinical outcome.

By adhering to the principle of keeping peritoneal surfaces moist and euthermic throughout surgical procedures, there is a reduction in adhesion formation and peritoneal cell integrity is maintained. We propose that you add a third arm to your study to evaluate the use of the Insuflow device in laparoscopic transperitoneal lymphadenectomy to more appropriately compare lymphadenectomy by the transperitoneal with the extraperitoneal laparoscopic approach. It is our opinion that by maintaining a more normal physiologic intra-abdominal environment by heating and humidifying the gas stream there will be an improvement in outcome and reduction in de novo adhesion formation.


American Journal of Obstetrics and Gynecology, Volume 185 • Number 3 • September 2001




Gasless laparoscopy and conventional instruments. The next phase of minimally invasive surgery.


Smith RS, Fry WR, Tsoi EK, Henderson VJ, Hirvela ER, Koehler RH, Brams DM, Morabito DJ, Peskin GW.


Department of Surgery, University of California, Davis-East Bay.


OBJECTIVE: To assess the capability of a retractor system that permits laparoscopic surgery without pneumoperitoneum and to determine if the system facilitates the use of conventional surgical instruments during minimally invasive surgery. DESIGN: Prospective evaluation and data collection with review. SETTING: University-affiliated county hospital. PATIENTS: Twenty-nine male and 29 female subjects evaluated prospectively via 27 trauma-related and 31 elective procedures. METHODS: Fifty-eight laparoscopic procedures were performed between July 1992 and February 1993 with a system consisting of an intra-abdominal fan retractor and an electrically powered mechanical arm using conventional surgical and laparoscopic instruments. RESULTS: Gasless laparoscopy was used in the evaluation of 27 patients with abdominal trauma (11 gunshot wounds, 11 stab wounds, and five blunt injuries). The need for celiotomy was obviated in 20 (74% of 27 cases. Three enterotomies, two diaphragmatic lacerations, and one gastric perforation were repaired with conventional instruments. Gasless laparoscopic techniques were also used in cholecystectomy (n = 26), diagnostic laparoscopy (n = 3), and appendectomy (n = 2). Exposure similar to that obtained by pneumoperitoneum was obtained in 30 (97% of 31 cases. One major (trocar tip enterotomy) and two superficial wound infections occurred in this group. The ability to use conventional surgical instruments was advantageous in several cases. CONCLUSIONS: Comparable exposure was achieved in this cohort of patients with gasless laparoscopy. The use of conventional surgical instruments provides an advantage with this technique. Further improvements in abdominal wall lift systems and modification of existing surgical instruments may expand the role of gasless laparoscopy.


Arch Surg. 1993 Oct;128(10):1102-7.



Cardiorespiratory effects of laparoscopy with and without gas insufflation.


McDermott JP, Regan MC, Page R, Stokes MA, Barry K, Moriarty DC, Caushaj PF, Fitzpatrick JM, Gorey TF.


Medical Center of Central Massachusetts, Worcester, USA.


BACKGROUND: Patients who are undergoing laparoscopic procedures can present with a number of ventilatory and circulatory problems. The use of a gasless technique for performing a laparoscopy by using a mechanical lifting device may potentially avoid such problems. OBJECTIVE: To compare the cardiorespiratory effects of laparoscopy with and without gas insufflation. METHODS: Twelve adult pigs were randomized to undergo a laparoscopy by using either carbon dioxide insufflation or mechanical elevation. Full invasive monitoring was performed preoperatively and at 10-minute intervals throughout the operative period. Parameters that were measured included blood gas determinations, mean arterial pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac output, stroke volume, and total peripheral resistance. RESULTS: Carbon dioxide insufflation unlike mechanical elevation led to a fall in PO2 and absorption of a significant quantity of CO2, resulting in hypercapnia, acidosis, and a consequent hyperdynamic circulation. CONCLUSION: These findings have significant implications for the use of CO2 insufflation for laparoscopy in patients with a compromised respiratory or cardiac status.


Arch Surg. 1995 Sep;130(9):984-8.



The impact of pneumoperitoneum, pneumoretroperitoneum, and gasless laparoscopy on the systemic and renal hemodynamics.


Chiu AW, Chang LS, Birkett DH, Babayan RK. 


Department of Surgery, National Yang-Ming University, School of Medicine, Taiwan, Republic of China.


BACKGROUND: The use of therapeutic laparoscopy has become widespread recently. It is important to assess the effects of gaseous and gasless laparoscopy on systemic and renal hemodynamics. STUDY DESIGN: A prospective controlled animal study was performed on 40 well-hydrated pigs. Systemic and renal hemodynamics were monitored during peritoneal insufflation, retroperitoneal insufflation, and abdominal wall lifting for a period of two hours. A laser Doppler flow meter was applied laparoscopically to measure the renal cortical tissue perfusion. RESULTS: Peritoneal insufflation of carbon dioxide to a pressure of 15 mm Hg elicited transient elevations of the aortic pressure and carotid arterial blood flow. Unilateral pneumoretroperitoneum caused a smaller change on systemic hemodynamics. Pneumoperitoneum and pneumoretroperitoneum caused oliguria. Superficial renal cortical blood flow reduction decreased by an average of 60 percent in the compressed kidney, and blood flow returned to the pre-insufflation level after the pressure was released. A gradual decrease of tissue perfusion in the contralateral kidney and a concomitant gradual increase of the intra-abdominal pressure were observed when pneumo-retroperitoneum was maintained for two hours. No significant changes in urinary output and in systemic and renal hemodynamics were found when the abdominal wall was lifted up with a force equivalent to 15 mm Hg. CONCLUSIONS:Significant systemic and renal hemodynamic changes were elicited in gaseous but not in gasless laparoscopy, which may explain the decreased urinary output observed during gaseous laparoscopy. Pneumoperitoneum caused greater systemic and renal hemodynamic alterations than pneumoretroperitoneum; however, the effects were transient and reversible after a period of two hours.


J Am Coll Surg. 1995 Nov;181(5):397-406.



Changes in urinary output and electrolytes during gaseous and gasless laparoscopy.


Chiu AW, Chang LS, Birkett DH, Babayan RK.


Department of Surgery, National Yang-Ming University, School of Medicine, Veterans General Hospital-Taipei, Taiwan, Republic of China.


Urological laparoscopy has gained increasing acceptance recently. Alterations in renal water and electrolyte homeostasis by carbon dioxide peritoneal insufflation, retroperitoneal insufflation and abdominal wall lifting were measured in 30 well-hydrated pigs over a 2-h period. Oliguria was observed after gaseous insufflation but not alter lifting the abdominal wall. Return to normal urinary output was observed at 30 min after release of pneumoretroperitoneum, and 60 min after pneumoperitoneum. Creatinine clearance declined, while the clearance rates of potassium, sodium and urea remained unchanged during peritoneal and retroperitoneal insufflation. An elevated serum aldosterone concentration was found which may mediate the increased urinary excretion of potassium and decreased urinary excretion of sodium found during peritoneal insufflation. Renal function remained stable, despite an elevation of serum creatine kinase being elicited after lifting the abdominal wall. In conclusion, significant changes in water and electrolyte homeostasis occurred gaseous, not gasless, laparoscopy in pigs.


Urol Res. 1996;24(6):361-6.



Gasless laparoscopic cholecystectomy: comparison of postoperative recovery with conventional technique.


Koivusalo AM, Kellokumpu I, Lindgren L.


Department of Anaesthesia, University of Helsinki, Finland.


We have compared, in a randomized study in 26 patients, immediate and late postoperative recovery after elective laparoscopic cholecystectomy using the gasless, mechanical abdominal wall lift method with conventional carbon dioxide pneumoperitoneum. After the gasless method, tracheal extubation was performed significantly earlier than after the conventional method (P < 0.01). End-tidal carbon dioxide concentrations were significantly higher after pneumoperitoneum for 30 min after operation (P < 0.01). In the conventional group, deviation in Maddox-Wing recordings from preoperative values remained at a significantly higher level during the 3-h recovery room period (P < 0.01). There was a positive correlation between the total amount of carbon dioxide used and duration of drowsiness (r = 0.61, P < 0.001) and the Maddox-Wing deviation (r = 0.62, P < 0.001). Postoperative nausea and vomiting, and right shoulder pain occurred less often after the gasless method (P < 0.05). Late recovery criteria (ability to drink, void and walk) in patients in the gasless group were fulfilled approximately 7 h earlier than in those in the pneumoperitoneum group (P < 0.01).Gasless laparoscopic cholecystectomy resulted in more uneventful and faster immediate and late postoperative recovery than conventional carbon dioxide pneumoperitoneum.


Br J Anaesth. 1996 Nov;77(5):576-80.



Impact of gas(less) laparoscopy and laparotomy on peritoneal tumor growth and abdominal wall metastases.


Bouvy ND, Marquet RL, Jeekel H, Bonjer HJ.


Department of Surgery, University Hospital, Dijkzigt, Rotterdam, The Netherlands.


OBJECTIVE: A tumor model in the rat was used to study peritoneal tumor growth and abdominal wall metastases after carbon dioxide (CO2) pneumoperitoneum, gasless laparoscopy, and laparotomy. SUMMARY BACKGROUND DATA: The role of laparoscopic resection of cancer is under debate. Insufflation of the peritoneal cavity with CO2 is believed to be a causative factor in the development of abdominal wall metastases after laparoscopic resection of malignant tumors. METHODS: In the solid tumor model, a lump of 350-mg CC-531 tumor cells was placed intraperitoneally in rats having CO2 pneumoperitoneum (n = 8), gasless laparoscopy (n = 8), or conventional laparotomy (n = 8). After 20 minutes, the solid tumor was removed through a laparoscopic port or through the laparotomy. In the cell seeding model, 5 x 10(5) CC-531 cells were injected intraperitoneally before CO2 pneumoperitoneum (n = 12), gasless laparoscopy (n = 12), or laparotomy (n = 12). All operative procedures lasted 20 minutes. After 6 weeks, in the solid tumor model and after 4 weeks in the cell seeding model, tumor growth was scored semiquantitatively. All results were analyzed using the analysis of variance. RESULTS: In the solid tumor model, peritoneal tumor growth in the laparotomy group was greater than in the CO2 pneumoperitoneum group (p < 0.01). Peritoneal tumor growth in the CO2 group was greater than in the gasless group (p < 0.01). The size of abdominal wall metastases was greater at the port site of extraction of the tumor than at the other port sites (p < 0.001). In the cell seeding model, peritoneal tumor growth was greater after laparotomy in comparison to CO2 pneumoperitoneum (p < 0.02). Peritoneal tumor growth in the CO2 group was greater than in the gasless group (p < 0.01). The port site metastases in the CO2 group were greater than in the gasless group (p < 0.01). CONCLUSIONS: The following conclusions can be made: 1) that direct contact between solid tumor and the port site enhances local tumor growth, 2) that laparoscopy is associated with less intraperitoneal tumor growth than laparotomy, and 3) that insufflation of CO2 promotes tumor growth at the peritoneum and is associated with greater abdominal wall metastases than gasless laparoscopy.


Ann Surg. 1996 Dec;224(6):694-700; discussion 700-1.



Abdominal wall lift versus carbon dioxide insufflation for laparoscopic resection of ovarian tumors.


Ogihara Y, Isshiki A, Kindscher JD, Goto H.


Department of Anesthesiology, University of Kansas Medical Center, Kansas City 66160-7415, USA.


STUDY OBJECTIVE: To evaluate and compare changes in pulmonary mechanics and stress hormone responses between abdominal wall lift (gasless) and carbon dioxide (CO2) insufflation laparoscopic surgery during controlled general anesthesia. DESIGN: Prospective, randomized clinical study. SETTING: Operating rooms at a university medical center. PATIENTS: 12 ASA physical status I and II female patients undergoing laparoscopic resection of ovarian tumors. INTERVENTIONS: Patients were divided into two groups of six each: the abdominal wall lift group and the CO2 pneumoperitoneum laparoscopic group. Following induction of anesthesia, patients were paralyzed and the trachea was intubated. Anesthesia was maintained with isoflurane and nitrous oxide (N2O) in oxygen. Throughout the procedure, patients were mechanically ventilated with a tidal volume of 10 ml/kg and a respiratory rate of 10 breaths per minute. MEASUREMENTS AND MAIN RESULTS: During the laparoscopic procedure, arterial blood gases, acid-base balance, pulmonary mechanics, stress-related hormones, and urine output were measured and recorded. In the CO2 pneumoperitoneum group, arterial CO2 tension increased (p < 0.01), dynamic pulmonary compliance decreased (p < 0.01), peak inspiratory airway pressure increased (p < 0.01), and plasma epinephrine (p < 0.05), norepinephrine (p < 0.05), dopamine (p < 0.01), and antidiuretic hormones (p < 0.05) increased significantly during the laparoscopic procedure as compared to the abdominal lift group. Adrenocorticotropic hormone and cortisol increased as compared to baseline value in both groups (p < 0.05). Urine output was significantly less (p < 0.01) in the CO2 pneumoperitoneum group than in the abdominal wall lift group. CONCLUSIONS: Abdominal wall lift laparoscopic surgery is physiologically superior to CO2 pneumoperitoneum laparoscopic surgery as seen during the conditions of this study. Abdominal wall lift laparoscopic surgery provides normal acid-base balance and a lesser degree of hormonal stress responses, it maintains urine output, and it avoids derangement of pulmonary mechanics.


J Clin Anesth. 1999 Aug;11(5):406-12.




The phygocytosis activity during conventional and gasless laparoscopy.  


Department of General Surgery, Johann-Wolfgang-Goethe-University, Theodor-Stern-Kai 7, D-60590 Frankfurt/Main, Germany.


Gutt CN, Heinz P, Kaps W, Paolucci V.


BACKGROUND: Numerous experimental and clinical investigations indicate that the mononuclear phagocyte system (MPS) has a relevant function in terms of physiological defense against tumor metastasis and bacterial infection. Consequently, a point of major interest is the influence of surgical techniques on the MPS function. METHOD: The model investigation examines the phagocytosis activity of the rat's MPS during conventional fundoplication (group 1, n = 10), laparoscopic fundoplication using a pneumoperitoneum (group 2, n = 10), and gasless laparoscopic fundoplication (group 3, n = 10). The MPS function is evaluated by an intravascular carbon clearance test (G. Biozzi). RESULTS: The fastest carbon elimination half-life was found in group 3. By way of contrast, there was a significant increase of carbon half-life in group 2 (p < 0.005). Even group 1 caused less MPS depression (p < 0.1) than group 2. CONCLUSION: Gasless laparoscopic procedures have a favorable effect on phagocytosis activity. The CO2 pneumoperitoneum seems to be the main reason for a decreased antigen elimination in laparoscopic treatments.


Surg Endosc. 1997 Sep;11(9):899-901.



Splanchnic and renal deterioration during and after laparoscopic cholecystectomy: a comparison of the carbon dioxide pneumoperitoneum and the abdominal wall lift method

Koivusalo AM, Kellokumpu I, Ristkari S, Lindgren L.


Department of Anaesthesia, Helsinki University Hospital, Finland.


Carbon dioxide (CO2) pneumoperitoneum together with an increased intraabdominal pressure (IAP) induces a hemodynamic stress response, diminishes urine output, and may compromise splanchnic perfusion. A new retractor method may be less traumatic. Accordingly, 30 ASA physical status I or II patients undergoing laparoscopic cholecystectomy were randomly allocated to a CO2 pneumoperitoneum (IAP 12-13 mm Hg) (control) or to a gasless abdominal wall lift method (retractor) group. Anesthesia and intravascular fluids were standardized. Direct mean arterial pressure (MAP), urine output, urine-N-acetyl-beta-D-glucosaminidase (U-NAG), arterial blood gases, gastric mucosal PCO2, and intramucosal pH (pHi) were measured. Normoventilation was instituted in all patients. MAP increased (P < 0.001) only with CO2pneumoperitoneum. Minute volume of ventilation had to be increased by 35% with CO2 insufflation. PaCO2 was significantly higher (P < 0.05) for 3 h postoperatively in the control group. Diuresis was less (P < 0.01) and U-NAG levels (P < 0.01) higher in the control group. The pHi decreased after induction of pneumoperitoneum up to three hours postoperatively and remained intact in the retractor group. We conclude that the retractor method for laparoscopic cholecystectomy ensures stable hemodynamics, prevents respiratory acidosis, and provides protection against biochemical effects, which reveal the renal and splanchic ischemia caused by CO2 insufflation. Implications: A mechanical retractor method (gasless) was compared with conventional CO2 pneumoperitoneum for laparoscopic cholestectomy. The gasless method ensured stable hemodynamics, prevented respiratory acidosis, and provided protection against the renal and splanchnic ischemia seen with CO2 pneumoperitoneum.


Anesth Analg. 1997 Oct;85(4):886-91.