B. Böhm

Pneumoperitoneum with carbon dioxide stimulates growth of malignant colonic cells

BACKGROUND Port-site recurrences have often been reported after laparoscopic surgery for malignant disease, and the pathogenesis is unknown. Whether different gases used to establish pneumoperitoneum have an influence on tumor cell growth has not been investigated. METHODS Tumor growth of colon adenocarcinoma DHD/K12/TRb was measured in a rat model after insufflation with either carbon dioxide or helium and in a control group. Tumor growth was evaluated in three experiments: (1) in vitro (n = 60), (2) ex vivo (n = 60), and (3) in vivo (n = 60). After insufflation, cell kinetics were determined in the first two experiments. In the third experiment, tumor growth was measured subcutaneously and intraperitoneally 5 weeks after insufflation. RESULTS Tumor cell growth increased significantly after insufflation with carbon dioxide in vitro (p < 0.03) and ex vivo (p < 0.05) compared with the control group, whereas helium did not stimulate cell growth. In vivo, subcutaneous tumor growth was promoted by carbon dioxide (131 +/- 55 mg) (p < 0.01) compared with helium (35 +/- 34 mg) and the control group (36 +/- 33 mg). Total intraperitoneal tumor weight was 717 +/- 320 mg in carbon dioxide group compared with helium (549 +/- 231 mg) and control group (570 +/- 321 mg). CONCLUSIONS The insufflation of carbon dioxide promotes tumor growth compared with helium and control in a rat model. Further studies should confirm these results before alternative gases should be recommended in laparoscopic surgery for malignant diseases.

Postoperative pain and fatigue after laparoscopic or conventional colorectal resections

AbstractBackground: Conventional colorectal resections are associated with severe postoperative pain and prolonged fatigue. The laparoscopic approach to colorectal tumors may result in less pain as well as less fatigue, and may improve postoperative recovery after colorectal resections. Methods: Sixty patients were included into a prospective randomized trial to determine the influence of laparoscopic (n= 30) or conventional (n= 30) resection of colorectal tumors on postoperative pain and fatigue. Major endpoints of the study were dose of morphine sulfate during patient-controlled analgesia (PCA), visual analog scale for pain while coughing (VASC), and visual analogue scale for fatigue (VASF). Efficacy of pain medication was assessed by visual analogue score at rest (VASR). Results: Preoperative age, sex, stage, and localization of tumors were comparable in both groups. The PCA dose of morphine given immediately after surgery until postoperative day 4 was higher in the conventional group (median, 1.37 mg/kg; 5–95 percentile 0.71–2.46 mg/kg) than the laparoscopic group (0.78 mg/kg; 0.24–2.38 mg/kg, p < 0.01). Postoperative VASR was comparable between both groups, but VASC was higher from the first to the seventh postoperative day (p < 0.01). Postoperative fatigue was higher after conventional than after laparoscopic surgery from the second to the seventh day (p < 0.05). Conclusions: This study confirms that analgetic requirements are lower and pain is less intense after laparoscopic than after conventional colorectal resection. Patients also experience less fatigue after minimal invasive surgery. Because of these differences, the duration of recovery is shortened, and the postoperative quality of life is improved after laparoscopic colorectal resections.

Inflammatory response after laparoscopic and conventional colorectal resections - results of a prospective randomized trial.

Abstract  Background: Short-term benefits of laparoscopic relative to conventional colorectal resections have been demonstrated in randomized controlled trials. It has been suggested that a diminished cytokine and acute-phase response may be responsible for these advantages. Methods: In a randomized controlled trial, patients underwent laparoscopic (n=30) or conventional (n=30) resection of colorectal tumors. Plasma levels of interleukin-1 receptor antagonist (IL-1RA), interleukin-6 (IL-6), interleukin-10 (IL-10), and C-reactive protein (CRP) were analyzed repeatedly. Postoperative peak levels and area under the curve values were calculated and compared between groups using the Mann-Whitney U-test. Results: Patient characteristics, preoperative cytokine, and CRP plasma levels were not different between each group. Postoperative peak concentrations of IL-6 (P=0.05) and CRP (P<0.001) and the overall postoperative plasma concentrations of IL-6 (P=0.03) and CRP (P=0.002) were lower in the laparoscopic than in the conventional group. Peak and overall IL-1RA (P=0.2; P=0.2) and IL-10 (P=0.4; P=0.6) plasma concentrations, respectively, were not different between groups. Conclusions: IL-6 and CRP plasma levels were lower after laparoscopic than conventional colorectal resections. The less intense inflammatory response may be an indicator of the milder surgical trauma inflicted by laparoscopic than conventional colorectal resection.

Does pneumoperitoneum with different gases, body positions, and intraperitoneal pressures influence renal and hepatic blood flow?

BACKGROUND Because of the well-known negative effects of carbon dioxide pneumoperitoneum on the hemodynamic and respiratory system, it was questionable how pneumoperitoneum may affect hepatic and renal blood flow. Therefore the influences of different gases, different intraperitoneal pressures, and different body positions on hepatic and renal blood flow were investigated in a porcine model. METHODS Cardiac and hemodynamic function were monitored by means of implanted catheters in the pulmonary artery and the femoral vein and artery. Renal and hepatic blood flow were recorded with a transonic volume flow meter placed at the renal and hepatic arteries and the portal vein. Eighteen animals were randomly assigned to receive one of three insufflation gases (carbon dioxide [CO2], argon, or helium. After baseline recording, one of three intraperitoneal pressures (8, 12, or 16 mm Hg) and one of three body positions (supine head up, or head down) were randomly chosen. After an adaptation time of 15 minutes, all data were recorded for 15 minutes. This was repeated until all nine combinations had been investigated. The end points of the study were blood flow in the hepatic and renal arteries and the portal vein, cardial output, systemic vascular resistance, and central venous pressure. RESULTS Total liver blood flow was reduced on relation to intraabdominal pressure, head-up position, and argon insufflation. Arterial hepatic blood flow was reduced by the head-up position and argon insufflation. Portal venous blood flow decreased with the pig in the head-up position, with increased intraabdominal pressure, and argon insufflation. Renal blood flow was reduced by the head-up position and increased pressure. There was no correlation (p < 0.6) between systemic hemodynamic parameters (cardiac output, central venous pressure, and systemic vascular resistance) and hepatic and renal blood flow. CONCLUSIONS Head-up position and intraperitoneal pressure greater than 12 mm Hg should be avoided during laparoscopic surgery because they compromise hepatic and renal blood flow. Argon insufflation impairs liver blood flow. However, helium may be advantageous compared with CO2 insufflation.

Inhibition of peritoneal tumor cell growth and implantation in laparoscopic surgery in a rat model

BACKGROUND The pathogenesis of portsite recurrences after laparoscopic surgery is still unknown, and a generally accepted approach to prevent tumor implantation does not exist. METHODS The effect of taurolidine and heparin on growth of colon adenocarcinoma DHD/K12/TRb was measured in vitro and in vivo. After incubation of the cells with heparin or taurolidine or both substances, cell kinetics were determined. In a rat model (n = 60), tumor cells were administered intraperitoneally, and pneumoperitoneum was established over 30 minutes. Rats received tumor cells, tumor cells + heparin, tumor cells + taurolidine, or tumor cells + taurolidine + heparin. RESULTS In vitro, tumor cell growth decreased after incubation with taurolidine and taurolidine/heparin. In vivo, intraperitoneal tumor weight was lower in rats receiving heparin (298 +/- 155 mg) and taurolidine (149 +/- 247 mg) compared with the control group (596 +/- 278 mg) but even less when both substances were combined (21.5 +/- 36 mg). CONCLUSION Heparin inhibits intraperitoneal tumor growth in vivo slightly, while taurolidine causes significant decrease of tumor cell growth in vitro as well as tumor take and intraperitoneal tumor growth in vivo.

The influence of laparotomy and laparoscopy on tumor growth in a rat model

AbstractBackground: The effects of laparotomy and laparoscopy with different gases on subcutaneous and intraperitoneal tumor growth have not been evaluated yet. Methods: Tumor growth of colon adenocarcinoma DHD/K12/TRb was measured in rats after laparotomy, laparoscopy with CO2 or air, and in control group. Cell kinetics were determined after incubation with carbon dioxide or air in vitro and tumor growth was measured subcutaneously and intraperitoneally after surgery in vivo. Results: In vitro, tumor cell growth increased significantly after incubation with air and CO2. In vivo, intraperitoneal tumor weight was increased after laparotomy (1,203 ± 780 mg) and after laparoscopy with air (1,085 ± 891 mg) and with CO2 (718 ± 690 mg) compared to control group (521 ± 221 mg) (p < 0.05). Subcutaneous tumor growth was promoted after laparotomy (71 ± 35 mg) and even more after laparoscopy with air (82 ± 45 mg) and CO2 (99 ± 55 mg) compared to control group (36 ± 33 mg). Conclusions: Insufflation of air and CO2 promote tumor growth in vitro. In vivo, intraperitoneal tumor growth seems to be promoted primarily by intraperitoneal air and subcutaneous tumor growth by CO2.

Prospective randomized blinded trial of pulmonary function, pain, and cosmetic results after laparoscopic vs microlaparoscopic cholecystectomy

AbstractBackground: The size of laparoscopic instruments has been reduced for use in abdominal video endoscopic surgery. However, it has yet to be proven that microlaparoscopic surgery will actually result in clinically relevant benefits for patients. Methods: Fifty patients were randomized in a blinded fashion to receive either elective laparoscopic (MINI), (n= 25) or microlaparoscopic (MICRO) (n= 25) cholecystectomy. Pulmonary function (FVC, FEV 1), analgesic consumption during patient-controlled analgesia (PCA), pain perception by visual analogue score (VAS), and the cosmetic result (by the patients self-assessment) were evaluated postoperatively as clinically relevant end points. Results: Age, sex, body mass index (BMI), preoperative pulmonary function, pain perception, and operative time were similar for the two groups. At 8:00 PM on the day of surgery, FVC (MINI: 1.96 L [range, 1.48–2.48]; MICRO: 2.13 L) [(range, 1.61.–2.50)] and FEV 1 (MINI: 1.17 L/sec) [range, 0.87–1.48]; MICRO: 1.34 L/sec [range, 1.05.–2.14] were also similar (each p= 0.5). From surgery to the 3rd postoperative day, cumulative PCA morphine doses were comparable (MINI: 0.15 mg/kg bw [range, 0.09–0.23]; MICRO: 0.21 mg/kg bw [range, 0.10–0.42]; p= 0.4), but overall VAS scores for pain while coughing were higher in the laparoscopic group (406 [range, 358–514]) than in the microlaparoscopic group (365 [range, 215–427]; p= 0.02). The cosmetic result was judged to be slightly superior by the microlaparoscopic patients (10 [range, 9–10]), as compared to those in the laparoscopic (9 [range, 8–10]) group (p= 0.04). Conclusion: Because microlaparoscopic cholecystectomy has some minor advantages over laparoscopic surgery, it should be considered for use in selected patients.

Subcutaneous Gentamycin Implant to Reduce Wound Infections After Loop-Ileostomy Closure: A Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUNDAfter loop-ileostomy closure subcutaneous wound infection is the most frequent postoperative complication. Implantation of local antibiotics has been shown to reduce the incidence of wound infection after different surgical procedures, therefore, a subcutaneous application of a gentamycin implant may also decrease infection rate after ileostomy-closure.METHODSWe conducted a randomized, double-blind, placebo-controlled trial to evaluate the effectiveness of a subcutaneous gentamycin–collagen implant to reduce wound infection after loop-ileostomy closure. Patients had the same perioperative treatment and standardized anastomotic and closure technique. A collagen sponge with gentamycin was used in the treatment group and an identical collagen implant without antibiotics was used in the placebo group.RESULTSEighty patients (40 per group) were included. There was no difference between the groups with respect to demographics or in the postoperative course. The total wound infection rate was 10 percent with no difference between the gentamycin (n = 4) and the collagen group (n = 4) (P = 1.0).CONCLUSIONSubcutaneous implantation of a gentamycin sponge yields no clinically relevant reduction of the wound infection rate after loop-ileostomy closure so that routine use is not recommended in this procedure.

Improvements in mechanical bowel preparation for elective colorectal surgery

PURPOSE: This study was undertaken to determine whether a mechanical bowel preparation with 2 liters of polyethylene glycol solution combined with a laxative (Group A) increases the acceptability of bowel preparation and reduces discomfort compared with 4 liters of polyethylene glycol solution (Group B). METHODS: One hundred patients undergoing an elective colorectal resection were included in a prospective, randomized study. Acceptability (nausea, vomiting, abdominal cramps, discomfort from insertion of the nasogastric tube, and anal discomfort) was assessed using visual analog scales. Efficacy of bowel lavage was scored intraoperatively by a blinded surgeon. RESULTS: Overall acceptability was 5.1±2.8 in Group A patients and 5.6±2.6 in Group B patients (P=0.5). The incidence and visual analog score for nausea, vomiting, anal discomfort, and cramps were not different between groups. Excellent efficacy of bowel preparation was shown in 94 percent of patients in Group A and 84 percent of patients in Group B (P=0.5). The incidence of septic complications was 2 percent in Group A patients and 12 percent in Group B patients (P=0.06). CONCLUSION: Because the acceptability of both cleansing regimens were not different, 2 liters of polyethylene glycol plus Prepacol®should be preferred because the amount of fluid administered to clean the bowel is reduced and the nasogastric tube can always be avoided.

Intermittent sequential compression of the lower limbs prevents venous stasis in laparoscopic and conventional colorectal surgery

PURPOSE: This study was designed to evaluate the influence of intraoperative intermittent sequential compression (ISC) on venous blood return from the lower limbs during laparoscopic and conventional colorectal colectomy. METHODS: Fifty patients undergoing laparoscopic (n=25) or conventional (n=25) colorectal surgery were included in a prospective study. Peak venous flow (PFV) and the cross-sectional area (CSA) of the femoral vein were assessed by Doppler ultrasound examination intraoperatively. RESULTS: Age, gender, and body mass index were comparable between both groups. Baseline PFV was 21±6.6 cm/s in the conventional and 18.4±6.4 cm/s in the laparoscopic group (P=0.2). ISC increased PFV to 156±29 percent of the baseline value in the conventional group and to 161±29 percent in the laparoscopic group. PFV decreased after abdominal insufflation to 127±19 percent of the baseline value in the laparoscopic group and after laparotomy to 134±27 percent in the conventional group (P=0.3). PFV decreased slightly in both groups during surgery but remained well above the baseline value. Baseline CSA was 1.02±0.17 cm2in the conventional group and 1±0.23 cm2in the laparoscopic group. ISC decreased CSA to 0.91±0.18 cm2(conventional) and 0.85±0.18 cm2(laparoscopic) after initiation of ISC. CSA was 0.92±0.18 cm2after abdominal insufflation in the laparoscopic group, and it was 0.93±0.18 cm2after laparotomy in the conventional group (P=0.4). During surgery, there were no differences in absolute CSA or CSA changes compared with the baseline value in both groups. Postoperative circumference of the calf and thigh were not different between both groups. Postoperative thromboembolic complications did not occur. CONCLUSION: ISC effectively increases venous blood flow from the lower limbs during conventional and laparoscopic colorectal resections and may decrease the risk of postoperative deep vein thrombosis. Therefore, ISC is strongly recommended in every prolonged laparoscopic procedure.