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Resolution of postoperative ileus in laparoscopic vs. open colectomy
April 1995
THE PREVENTION OF POST-SURGICAL ADHESIONS WITH A BIOABSORBABLE MEMBRANE IN AN EXPERIMENTAL SURGERY MODEL Burns JW, Skihner KJ, Burgess L, and Ro~e R; Biopolymers Research Department, Genzyme Corporation Cambridge Massachusetts. Becker J: Department of Surgery, Boston University School of Medicine, Boston Massachusetts. Post-surgical adhesions occur in a reported 67% to 93% of abdominal surgery patients. The morbidity caused by abdominal adhesions inc}ude chronic pain, difficult reoperative procedures, and bowel obstruction. The goal of this study was to (1) establish an animal model for the study of peritoneal adhesions, and r (2) evaluate the ability of a bioabsorbable membrane (HAL-FTM B'oabsorbable Membrane) to reduce adhesion formation. HAL-FTM membrane is a composite of the naturally occurring polysaccharide hyaluronic acid (HA) and carboxymethylcellulose (CMC). HAL-FTM membrane is designed to prov de a temporary hydrophilic barrier between damaged tissue surfaces duhng repetitoneelization, after which adhesions do not form. In 15 adult female New Zealand White rabbits a 3 in. x 5 in. defect was created in the ventrar abdominal wall (sidewall) by carefully dissecting away the peritoneum to the underlying muscle layer. The defect border was enclosed with 4-0 continuous silk suture to induce ischemia. The ventral and dorsal surfaces of the animal's cecum were then abraded in a standard fashion to induce punctate bleeding. Following repositioning of the cecum beneath the sidewall defect, the rabbits were randomly placed in a non-treatment control group or in a group that had either 1 or 3 HAL-FTM membranes (5 in x 6 ini placed between the ventral abraded cecum and the sidewall defect. Seven days later the extent (0-4 scale) and severity (0-3 scale) of adhesions to the sidewall defest were scored and the incidence of adhesions noted to the ventral cecum. Upon reoperalion, 60% (3/5) of the non-treatment control animals had at least one adhesion tO the ventral cecum or to the sidewall defect, while 0% (0/10) of animals that received I or 3 membranes had adhesions to the ventral cecum or sidewall defect (p < 0.001 Chi-square analysis). The total adhesion score to the sidewall defect (sum of extent and severity) in th e control and membrane groups was also significantly different; 2.6 +1.6 compared to 0.0 + 0.0 for the non-treatment and membrane groups respectively (p < 0.001 Mann-Whitney U Test). Histological examination of tissues and organs showed no untoward cellular response to the membrane. The results of this study demonstrate (1) that the rabbit sidewall defect/cecal abrasion model can generate peritoneal adhesions in a significant number of control animals, (2) that HAL-FTM membrane significantly reduces the formation of peritoneal adhesions in an experimental surgery model, and (3) overlaying .. of HAL-FTM membrane multiple membranes does not adversely affect the ablhty to prevent adhesions. We conclude that HAL-FTM membrane can prevent postsurgical adhesions by providing a temporary barrier to damaged peritoneum during the critical phases of wound repair when adhesions can form.
RENAL ADENosINE EXCRETION IN PATIENTS RECEIVING AMPHOTERICIN-B. M.A. Carlson; A.A.B. Ferraz. R.E. Condon, Department of Surgery, Medical College of Wisconsin. Milwaukee, Wl The intrinsic mechanism by which Amphotericin-B (AmB) produces nephrotoxicity in humans is not known. Both AmB and adenosine (ADO) have been shown to cause renal vasoconstriction in animals that may contribute to nephrotoxicity. ADO is released by many ischemic tissues. ADO released by the ischemic kidney can be detected in the urine. We hypothesized that Arab administration to patients would be associated with renal isehemia resulting in increased renal excretion of ADO and decreased urinary volume Output. Twenty hospitalized patients not in renal failure who were receiving daily intravenous AmB (20-50 rag) infusions had urine collected through their Foley catheter for 1 hr before and 2 Ins during the AmB infusion. An aliquot of each urine collection was immediately precipitated with concentrated perchloric acid to remove protein and cellular elements, centrifuged, and the supernatant assayed for ADO using high performance liquid chromatography. ADO was determined in preliminary experiments to be stable in urine at room temperature for 2 hrs (data not shown). The average excretion of ADO in the urine was 0.186 (range 0.0005-1.197) ~tmol/hr and 0.125 (range 0.0006-0.6737) pmol/hr during Arab infusion (p<0.05, Wilcoxon rank test). The mean urine output was 196 (range 4-500) ml/hr before and 122 (range 14-400) ml/hr during AmB infusion (p<0.0l). Both urinary vohine output and renal excretion of ADO decrease with Arab infusion. Arab does not appear to cause sufficient renal ischemia to result in release of ADO. The decreased urine flow and excretion of ADO that we observed during ArnB infusion is probably a consequence of decreased renal blood and tubular flow due to some mechanism other than tubular ischemia.
SSAT
• THE W E I G H T R E D U C T I O N O P E R A T I O N O F CHOICE, VERTICAL BANDED GASTROPLASTY OR GASTRIC BYPASS? J.F. C a m e l l a and R. F. CaDella, Department of Surgery, St. Luke's-Roosevelt Hospital Center. N e w York, N e w York. Bariatric surgeons continue to debate the p r o c e d u r e of choice for weight reduction. The discussion has centered around the two m o s t commonly performed bariatric procedures, vertical banded gastroplasty and gastric bypass. In this study we compare 218 consecutively performed vertical banded gastroplasties (VBG) and 502 vertical banded gastroplasty-gastric bypasses (VBG-GBP), a form of gastric bypass/ for mortality, early and late complications requiring reoperation, and weight loss at 4 years. There was a single mortality in the VBG group. There were no early complications requiring reoperation for the VBG group and three f o r the VBG-GBP patients (0.5%). In the VBG group 44 (23%) patients underwent reoperation for late complications compared with 52 (10%) for the VBG-GBP group. Among the 109 VBG and 83 VBGGBP patients who have been followed for 4 or more years, their p e r c e n t a g e o f e x c e s s weight lost was 49 and 64% respectfully (p<.001). When weight loss and rate of r e o p e r a t i o n are considered, our data suggests VBG-GBP is preferable to VBG.
RESrLuTION OF POSTOPERATIVE ILEUS IN LAPAROSCOPIC VS. OPEN COLECTOMY M.A. Carlson and C.T. Frantzides. Department of Surgery, Medical College of Wisconsin, Milwaukee Wisconsin. It has been assumed that a laparoscopic procedure has a shorter period of postoperative ileus compared to the equivalent open procedure. The purpose of this study was to document any difference in the period of ileus between dogs undergoing either a laparoscopic or open colon resection. The period of ileus would be determined by noting the return of organized myoelectric activity, an event which has been shown previously to approximate the clinical resolution of ileus. Ten dogs underwent laparotomy and were implanted with serosal electrodes, 6 on the small bowel and 4 on the tranverse and left colon. After the animals recovered from instrumentation (3 weeks), 5 underwent laparoseopie and 5 underwent open right hemicolectomy. None of the dogs received any opioid analgesic. Recording of myoelectric activity was begun immediately after operation and continued for one week. The time at which the migrating myoelectric complex (MMC), the migrating colonic complex (/vlCC), and phase 2 activity (P2) returned was determined by visual analysis of myoalectric recording.
Laparoscopic Open
MMC (min + sd)
MCC (min + sd)
454 _+_88
353 +. 86
P2 (rain _+sd) 1958 + 301
588 + 233
368 + 150
2544 +. 293
None of these differences were significant (unpaired t-test, p > 0.05). There is no demonstrable difference in the time required for the return of organized myoelectric activity in the dog undergoing a laparoscopic vs. an open colectomy. With this data we cannot verify the purported short period of ileus in the patient undergoing a laparosoopic procedure; this clinical observation may be the result of observer bias.
A1215
THE PREVENTION OF POST-SURGICAL ADHESIONS WITH A BIOABSORBABLE MEMBRANE IN AN EXPERIMENTAL SURGERY MODEL Burns JW, Skihner KJ, Burgess L, and Ro~e R; Biopolymers Research Department, Genzyme Corporation Cambridge Massachusetts. Becker J: Department of Surgery, Boston University School of Medicine, Boston Massachusetts. Post-surgical adhesions occur in a reported 67% to 93% of abdominal surgery patients. The morbidity caused by abdominal adhesions inc}ude chronic pain, difficult reoperative procedures, and bowel obstruction. The goal of this study was to (1) establish an animal model for the study of peritoneal adhesions, and r (2) evaluate the ability of a bioabsorbable membrane (HAL-FTM B'oabsorbable Membrane) to reduce adhesion formation. HAL-FTM membrane is a composite of the naturally occurring polysaccharide hyaluronic acid (HA) and carboxymethylcellulose (CMC). HAL-FTM membrane is designed to prov de a temporary hydrophilic barrier between damaged tissue surfaces duhng repetitoneelization, after which adhesions do not form. In 15 adult female New Zealand White rabbits a 3 in. x 5 in. defect was created in the ventrar abdominal wall (sidewall) by carefully dissecting away the peritoneum to the underlying muscle layer. The defect border was enclosed with 4-0 continuous silk suture to induce ischemia. The ventral and dorsal surfaces of the animal's cecum were then abraded in a standard fashion to induce punctate bleeding. Following repositioning of the cecum beneath the sidewall defect, the rabbits were randomly placed in a non-treatment control group or in a group that had either 1 or 3 HAL-FTM membranes (5 in x 6 ini placed between the ventral abraded cecum and the sidewall defect. Seven days later the extent (0-4 scale) and severity (0-3 scale) of adhesions to the sidewall defest were scored and the incidence of adhesions noted to the ventral cecum. Upon reoperalion, 60% (3/5) of the non-treatment control animals had at least one adhesion tO the ventral cecum or to the sidewall defect, while 0% (0/10) of animals that received I or 3 membranes had adhesions to the ventral cecum or sidewall defect (p < 0.001 Chi-square analysis). The total adhesion score to the sidewall defect (sum of extent and severity) in th e control and membrane groups was also significantly different; 2.6 +1.6 compared to 0.0 + 0.0 for the non-treatment and membrane groups respectively (p < 0.001 Mann-Whitney U Test). Histological examination of tissues and organs showed no untoward cellular response to the membrane. The results of this study demonstrate (1) that the rabbit sidewall defect/cecal abrasion model can generate peritoneal adhesions in a significant number of control animals, (2) that HAL-FTM membrane significantly reduces the formation of peritoneal adhesions in an experimental surgery model, and (3) overlaying .. of HAL-FTM membrane multiple membranes does not adversely affect the ablhty to prevent adhesions. We conclude that HAL-FTM membrane can prevent postsurgical adhesions by providing a temporary barrier to damaged peritoneum during the critical phases of wound repair when adhesions can form.
RENAL ADENosINE EXCRETION IN PATIENTS RECEIVING AMPHOTERICIN-B. M.A. Carlson; A.A.B. Ferraz. R.E. Condon, Department of Surgery, Medical College of Wisconsin. Milwaukee, Wl The intrinsic mechanism by which Amphotericin-B (AmB) produces nephrotoxicity in humans is not known. Both AmB and adenosine (ADO) have been shown to cause renal vasoconstriction in animals that may contribute to nephrotoxicity. ADO is released by many ischemic tissues. ADO released by the ischemic kidney can be detected in the urine. We hypothesized that Arab administration to patients would be associated with renal isehemia resulting in increased renal excretion of ADO and decreased urinary volume Output. Twenty hospitalized patients not in renal failure who were receiving daily intravenous AmB (20-50 rag) infusions had urine collected through their Foley catheter for 1 hr before and 2 Ins during the AmB infusion. An aliquot of each urine collection was immediately precipitated with concentrated perchloric acid to remove protein and cellular elements, centrifuged, and the supernatant assayed for ADO using high performance liquid chromatography. ADO was determined in preliminary experiments to be stable in urine at room temperature for 2 hrs (data not shown). The average excretion of ADO in the urine was 0.186 (range 0.0005-1.197) ~tmol/hr and 0.125 (range 0.0006-0.6737) pmol/hr during Arab infusion (p<0.05, Wilcoxon rank test). The mean urine output was 196 (range 4-500) ml/hr before and 122 (range 14-400) ml/hr during AmB infusion (p<0.0l). Both urinary vohine output and renal excretion of ADO decrease with Arab infusion. Arab does not appear to cause sufficient renal ischemia to result in release of ADO. The decreased urine flow and excretion of ADO that we observed during ArnB infusion is probably a consequence of decreased renal blood and tubular flow due to some mechanism other than tubular ischemia.
SSAT
• THE W E I G H T R E D U C T I O N O P E R A T I O N O F CHOICE, VERTICAL BANDED GASTROPLASTY OR GASTRIC BYPASS? J.F. C a m e l l a and R. F. CaDella, Department of Surgery, St. Luke's-Roosevelt Hospital Center. N e w York, N e w York. Bariatric surgeons continue to debate the p r o c e d u r e of choice for weight reduction. The discussion has centered around the two m o s t commonly performed bariatric procedures, vertical banded gastroplasty and gastric bypass. In this study we compare 218 consecutively performed vertical banded gastroplasties (VBG) and 502 vertical banded gastroplasty-gastric bypasses (VBG-GBP), a form of gastric bypass/ for mortality, early and late complications requiring reoperation, and weight loss at 4 years. There was a single mortality in the VBG group. There were no early complications requiring reoperation for the VBG group and three f o r the VBG-GBP patients (0.5%). In the VBG group 44 (23%) patients underwent reoperation for late complications compared with 52 (10%) for the VBG-GBP group. Among the 109 VBG and 83 VBGGBP patients who have been followed for 4 or more years, their p e r c e n t a g e o f e x c e s s weight lost was 49 and 64% respectfully (p<.001). When weight loss and rate of r e o p e r a t i o n are considered, our data suggests VBG-GBP is preferable to VBG.
RESrLuTION OF POSTOPERATIVE ILEUS IN LAPAROSCOPIC VS. OPEN COLECTOMY M.A. Carlson and C.T. Frantzides. Department of Surgery, Medical College of Wisconsin, Milwaukee Wisconsin. It has been assumed that a laparoscopic procedure has a shorter period of postoperative ileus compared to the equivalent open procedure. The purpose of this study was to document any difference in the period of ileus between dogs undergoing either a laparoscopic or open colon resection. The period of ileus would be determined by noting the return of organized myoelectric activity, an event which has been shown previously to approximate the clinical resolution of ileus. Ten dogs underwent laparotomy and were implanted with serosal electrodes, 6 on the small bowel and 4 on the tranverse and left colon. After the animals recovered from instrumentation (3 weeks), 5 underwent laparoseopie and 5 underwent open right hemicolectomy. None of the dogs received any opioid analgesic. Recording of myoelectric activity was begun immediately after operation and continued for one week. The time at which the migrating myoelectric complex (MMC), the migrating colonic complex (/vlCC), and phase 2 activity (P2) returned was determined by visual analysis of myoalectric recording.
Laparoscopic Open
MMC (min + sd)
MCC (min + sd)
454 _+_88
353 +. 86
P2 (rain _+sd) 1958 + 301
588 + 233
368 + 150
2544 +. 293
None of these differences were significant (unpaired t-test, p > 0.05). There is no demonstrable difference in the time required for the return of organized myoelectric activity in the dog undergoing a laparoscopic vs. an open colectomy. With this data we cannot verify the purported short period of ileus in the patient undergoing a laparosoopic procedure; this clinical observation may be the result of observer bias.
A1215