Search PubMed⌕ Search

Biomedical subjects

Michel Gagner

Publications and source records attributed to Michel Gagner.

At least 37 records · Page 2Linked to original sources
PubMed2004

Subcutaneous endoscopic fasciotomy in a porcine model of abdominal compartment syndrome: a feasibility study.

PURPOSE: Treatment of abdominal compartment syndrome (ACS) involves abdominal decompression via a laparotomy, which can result in significant wound-related morbidity. Our aim was to determine if subcutaneous endoscopic abdominal fasciotomy in a porcine model of ACS is feasible and what effect it may have on intra-abdominal pressure (IAP) and superior mesenteric artery (SMA) blood flow. MATERIALS AND METHODS: A total of 6 female pigs weighing 50 kg each were used for the study. Each animal underwent placement of an arterial line, pulmonary artery catheter, SMA blood flow probe, IAP catheter, and intra-abdominal saline infusion line. After endoscopic dissection of a subcutaneous pocket overlying the rectus muscles, saline was infused into the abdomen to a pressure of 40 mm Hg. Physiologic parameters were measured before and after bilateral endoscopic anterior rectus fasciotomies were performed, and analyzed with a paired t-test. RESULTS: Mean subcutaneous dissection time was 42.5 +/- 11.3 minutes, and mean fasciotomy time was 5.5 +/- 2.3 minutes. There were no significant changes in heart rate, cardiac output, pO(2), or pH during the experiment. IAP increased exponentially as fluid was instilled into the abdomen. SMA blood flow decreased reliably and linearly with increasing IAP. Mean baseline IAP was 4.0 +/- 1.7 mm Hg. IAP decreased from 37 mm Hg to 25 mm Hg after fasciotomy (P < 0.001). Mean baseline SMA blood flow was 629 +/-164 mL/min. SMA blood flow improved from 265 mL/min to 389 mL/min after fasciotomy (P< 0.01). CONCLUSION: Subcutaneous endoscopic abdominal fasciotomy is feasible and appears to lower IAP and raise SMA blood flow in a porcine model of ACS.

Abdomen↗
PubMed2004

The early effect of the Roux-en-Y gastric bypass on hormones involved in body weight regulation and glucose metabolism.

OBJECTIVE: To evaluate the early effect of Roux-en-Y (RYGB) gastric bypass on hormones involved in body weight regulation and glucose metabolism. SIGNIFICANT BACKGROUND DATA: The RYGB is an effective bariatric procedure for which the mechanism of action has not been elucidated yet. Reports of hormonal changes after RYGB suggest a possible endocrine effect of the operation; however, it is unknown whether these changes are the cause or rather the effect of surgically induced weight loss. We speculated that if the mechanism of action of the RYGB involves an endocrine effect, then hormonal changes should occur early after surgery, prior to substantial body weight changes. METHODS: Ten patients with a mean preoperative body mass index (BMI) of 46.2 kg/m (40-53 kg/m) underwent laparoscopic RYGB. Six patients had type 2 diabetes treated by oral hypoglycemic agents. Preoperatively and 3 weeks following surgery, all patients were tested for fasting glucose, insulin, glucagon, insulin-like growth factor 1 (IGF-1), leptin, gastric inhibitory polypeptide (GIP), glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK), adrenocorticotropic hormone (ACTH), corticosterone, and neuropeptide Y (NPY). RESULTS: Changes in mean BMI were rather minimal (43.2 kg/m; P = not significant), but there was a significant decrease in blood glucose (P = 0.005), insulin (P = 0.02), IGF-1 (P < 0.05), leptin (P = 0.001), and an increase in ACTH levels (P = 0.01). The other hormones were not significantly changed by surgery. All the 6 diabetic patients had normal glucose and insulin levels and did not require medications after surgery. The RYGB reduced GIP levels in diabetic patients (P < 0.01), whereas no changes in GIP levels were found in nondiabetics. CONCLUSIONS: Roux-en-Y gastric bypass determines considerable hormonal changes before significant BMI changes take place. These results support the hypothesis of an endocrine effect as the possible mechanism of action of RYGB.

Adrenocorticotropic Hormone↗
PubMed2004

Intraluminal migration of bovine pericardial strips used to reinforce the gastric staple-line in laparoscopic bariatric surgery.

A 41-year-old morbidly obese woman (BMI 40.8) underwent elective laparoscopic biliopancreatic diversion with duodenal switch. The operation involved: sleeve gastrectomy, division of duodenum, creation of a duodenoenterostomy, and creation of a distal ileoenteric anastomosis. With laparoscopic stapling, bleeding is often a problem along the sleeve gastrectomy staple-line. To reduce this risk, we used bovine pericardial strips to reinforce the staple-line throughout its length. 4 weeks postoperatively, the patient was found to have fragments of pericardium in her vomitus, indicating intraluminal migration of the reinforcing strips. Her subsequent course has been uneventful. This represents the first report of such migration. Indications, benefits, complications and risks of using bovine pericardium to reinforce gastric staple-lines in laparoscopic bariatric surgery are discussed.

Adult↗
PubMed2004

Current status of the laparoscopic approach to liver resection.

UNLABELLED: We present the current status of laparoscopic approach to liver resection. Indications, surgical techniques, complications, and results are based on a review of the literature. RESULTS: Over 700 laparoscopic liver procedures have been reported since 1991. A vast majority (70%) of the procedures were performed for benign lesions. The remaining 30% were malignant tumors. Cyst fenestration and unroofing was the most frequently performed laparoscopic liver procedure (245 patients). Overall morbidity was 12% (56 patients). The overall conversion rate was 11% (36 patients). CONCLUSION: Laparoscopic liver resection is feasible, with acceptable morbidity and mortality. Results should be confirmed in further prospective studies, especially for resection of malignant tumors.

Carcinoma, Hepatocellular↗
PubMed2004

Staple-line reinforcement techniques with different buttressing materials used for laparoscopic gastrointestinal surgery: a new strategy to diminish perioperative complications.

Many techniques have been analysed to reduce the risk of perioperative anastomotic leakage and bleeding. No specific resection technique with either linear or circular stapling devices has been shown to be superior in preventing these complications. Reinforcement of staple lines with various buttressing materials is a new strategy used to diminish or eliminate anastomotic leaks and haemorrhage. In this chapter, varying reinforcement techniques with different materials are compared. The available literature has been reviewed thoroughly for relevant data regarding stapled reinforcement techniques and minimizing anastomotic leaks and haemorrhage. Reported data show non-absorbable, semi-absorbable, and bioabsorbablematerials available for gastrointestinal (GI) resections. Semi-absorbable xenomaterials (Bovine Pericardial Strips and Bovine Collagen Strips; Shellhigh No-Reaction Vascupatch, Milburn, NJ, USA), non-absorbable expanded polytetrafluoroethylene (ePTFE; W.L. Gore, Elkton, MD, USA) and absorbable poly (L-lactic acid-co-epsilon-caprolactomne) film are compared. Non-absorbable and semi-absorbable materials show many differences. Absorbable polymer membranes demonstrate marked benefits. Staple-line reinforcement used for laparoscopic GI surgery is a relatively new strategy, most probably improving perioperative outcome only if proper buttressing material is used. To decrease anastomotic complications, using an absorbable polymer membrane as staple-line reinforcement material is reliable and efficacious.

Biocompatible Materials↗
PubMed2003

Robotics and general surgery.

Robotics are now being used in all surgical fields, including general surgery. By increasing intra-abdominal articulations while operating through small incisions, robotics are increasingly being used for a large number of visceral and solid organ operations, including those for the gallbladder, esophagus, stomach, intestines, colon, and rectum, as well as for the endocrine organs. Robotics and general surgery are blending for the first time in history and as a specialty field should continue to grow for many years to come. We continuously demand solutions to questions and limitations that are experienced in our daily work. Laparoscopy is laden with limitations such as fixed axis points at the trocar insertion sites, two-dimensional video monitors, limited dexterity at the instrument tips, lack of haptic sensation, and in some cases poor ergonomics. The creation of a surgical robot system with 3D visual capacity seems to deal with most of these limitations. Although some in the surgical community continue to test the feasibility of these surgical robots and to question the necessity of such an expensive venture, others are already postulating how to improve the next generation of telemanipulators, and in so doing are looking beyond today's horizon to find simpler solutions. As the robotic era enters the world of the general surgeon, more and more complex procedures will be able to be approached through small incisions. As technology catches up with our imaginations, robotic instruments (as opposed to robots) and 3D monitoring will become routine and continue to improve patient care by providing surgeons with the most precise, least traumatic ways of treating surgical disease.

Adrenalectomy↗
PubMed2003

Laparoscopic gastric bypass versus laparoscopic adjustable gastric banding: a comparative study of 1,200 cases.

BACKGROUND: Indications for and results of laparoscopic adjustable gastric banding (LAGB) and laparoscopic gastric bypass (LGB) are still controversial, especially between Europe and the United States. The recent availability of gastric bandings in the United States made it necessary to compare the two techniques. STUDY DESIGN: We compared a series of 456 LGB to a series of 805 LAGB performed in two different institutions. Body mass index (BMI), complication rate, mortality, and excess weight loss (EWL) after 3, 6, 12, and 18 months were obtained. A Fischer's exact test and a Student t test with covariance analysis were used for statistical analysis. RESULTS: Results are expressed as a mean +/- standard deviation, comparing LGB with LAGB. Preoperative BMI was 49.4 +/- 8.3 kg/m(2) versus 42.2 +/- 4.9 kg/m(2) (p = 0.0001), respectively. Perioperative major complication rates were 2.0% versus 1.3% (NS), and the early postoperative major complication rates were 4.2% versus 1.7% (p = 0.02), respectively. Mortality rate was 0.4% versus 0% (NS), respectively. The global EWL was 36.3% for LGB versus 14.7% for LAGB at 3 months (p < 0.0001), 51.6% versus 21.9% at 6 months (p < 0.0001), 67.0% versus 33.3% at 12 months (p < 0.0001), and 74.6% versus 40.4% at 18 months (p < 0.0001), respectively. Longterm followup for the LAGB group showed an EWL of 47% at 2 years, 56% at 3 years, and 58% at 4 years. Patients were sorted after their preoperative BMI (30 to 40, 40 to 50, and 50 to 60 kg/m(2)). The EWL at 3, 6, 12, and 18 months was statistically superior in the LGB group, for any BMI ranges. CONCLUSIONS: These data suggest that LGB provides a higher EWL at 18 months, compared with LAGB, and this was true for any preoperative BMI range. It is associated with a higher early postoperative complication rate.

Adolescent↗
PubMed2003

Early experience with computer-mediated flexible circular stapling technique for upper gastrointestinal anastomosis.

BACKGROUND: Creating the proximal anastomosis in laparoscopic biliopancreatic diversion with duodenal switch (LBPD-DS) and Roux-en-Y gastric bypass (LRYGBP) is a critical step in ensuring the success of the procedures. The aim of this study was to assess the safety and efficiency of performing this anastomosis using a flexible, computerized, circular stapling device. METHOD: We prospectively monitored the use of a newly FDA-approved stapling device (SurgASSIST, Power Medical Intervention) for the construction of the proximal anastomosis by a variety of approaches and reviewed the charts of 10 patients. RESULTS: We successfully constructed 9 out of 10 proximal anastomoses: 2 gastro-jejunostomies and 7 duodeno-ileostomies, without any signs of leakage. In 2 patients, the stapling technique involved a transpyloric instrumental passage; both were complicated by the difficulty to pass either the flexible scope or the anvil through the narrow pyloric lumen. In 5 patients, the anvil was placed directly through a duodenotomy and no technical problems were encountered. The median time for performing the proximal anastomosis was 19 minutes (range 9-55). There were no postoperative complications in any patients. CONCLUSIONS: Stapling using the SurgASSIST was feasible and safe for performing laparoscopic anastomoses in bariatric bypass procedures. A duodenotomy for direct placement of the anvil into the postpyloric region seems to be most feasible for duodenoileostomies, while transoral passage of the anvil can be recommended for gastro-jejunostomies. In its current form, we do not recommend transoral placement of the flexible shaft of the SurgASSIST device. Further clinical trials need to be performed for comparison with existing devices.

Adult↗
PubMed2003

Laparoscopic reoperative sleeve gastrectomy for poor weight loss after biliopancreatic diversion with duodenal switch.

BACKGROUND: The revisional surgery for patients with inadequate weight loss after biliopancreatic diversion with duodenal switch (BPD/DS) is controversial. It has not yet been determined whether a common channel should be shortened or gastric pouch volume reduced. Since the revision of the distal anastomosis remains technically difficult and associated with possible complications, we turned our attention to the reduction of gastric sleeve volume. This operation is more feasible and potential complications are less probable. PATIENT AND METHOD: We present the case of a 47-year-old women with a life-long history of morbid obesity. She was operated on in January 2000 with a laparoscopic BPD/DS with 100 ml gastric pouch, 150 cm of alimentary limb and 100 cm of common channel. Before this operation, her weight was 170 kg, with BMI 64 kg/m(2). She lost most of her excess weight within 17 months after surgery and was regaining weight at 77 kg and BMI 29 kg/m(2). Upper GI series showed a markedly dilated gastric pouch. Her second surgery consisted of a laparoscopic sleeve partial gastrectomy along the greater curvature using endo GIA staplers with bovine pericardium for reinforcement of the stapler line. RESULTS: No postoperative complications occurred. The patient was discharged on the first postoperative day. Significant further weight reduction was noted, and at 10 months after surgery, her weight is 61 kg with BMI 22. CONCLUSION: A repeat laparoscopic gastric sleeve resection was performed for inadequate weight loss after BPD/DS, and resulted in further weight reduction.

Biliopancreatic Diversion↗
PubMed2003

Taking posterior rectus sheath laparoscopically to reinforce the gastrojejunostomy in laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: The Roux-en-Y gastric bypass (RYGBP) is now performed laparoscopically widely with low morbidity and mortality. However, in some cases long-term adequate weight loss is not satisfied because of dilatation of the gastrojejunostomy. Therefore, a prosthetic material and bio-membranes have been used to prevent dilatation. In this study, we used posterior rectus sheath by laparoscopy, to evaluate feasibility and safety of the procedure. METHODS: 20 Yorkshire pigs, under general anesthesia, had a standard laparoscopic RYGBP. In addition, 10 had their gastrojejunostomy anastomosis wrapped with 2x10 cm posterior rectus sheath. Clinical and operative outcome after operation were compared with the control group of laparoscopic RYGBP cases. RESULTS: The median weight of the pigs was 46.1 kg (range 42-51) in the posterior rectus sheath-applied group and 45.2 kg (range 42-49) in the control group. All gastrojejunostomies in the posterior rectus sheath-applied group were successfully reinforced laparoscopically. Both groups loss weight compared with their normal growth weight, but there was no significant difference in the median weight loss between the two groups. Two pigs in the posterior rectus sheath-applied group developed a stenosis at the gastrojejunostomy anastomosis following RYGBP. All pigs in the posterior rectus sheath-applied group were found to develop hypertrophic smooth muscle and connective tissue scarring at the gastrojejunostomy on histologic examination. CONCLUSION: Laparoscopic application of posterior rectus sheath around the gastrojejunostomy in laparoscopic RYGBP is feasible and safe. The sheath-applied group developed stenosis and connective tissue scarring. Additional research is needed to evaluate effectiveness in preventing dilation of the anastomosis.

Abdominal Muscles↗
PubMed2003

Laparoscopic adjustable gastric banding with duodenal switch for morbid obesity: technique and preliminary results.

BACKGROUND: The procedure of choice for morbid obesity remains controversial. One of the most effective treatments is the biliopancreatic diversion with duodenal switch (BPD/DS), which is, however, associated with a significant morbidity rate. Adjustable gastric banding (AGB) by the laparoscopic approach is an easier procedure with the intent to reduce complication rates. It replaced the sleeve gastrectomy in this study. The objective was to assess the feasibility and safety of this new laparoscopic treatment. METHODS: AGB with duodenal switch (DS) was performed laparoscopically with 7 trocars. A gastric band was appropriately placed below the gastroesophageal junction, followed by BPD/DS with a 250-cm alimentary channel and a 100-cm common channel. RESULTS: All 5 patients were women, with mean preoperative BMI 52.2 kg/m(2) (40.6 to 64.4). The operations were performed via laparoscopy in a mean of 206 +/- 35 minutes. There was no postoperative complication, infection or conversion. Mean hospital stay was 8.8 days (8-11). At 12 months, mean BMI is 35.8 kg/m(2) (26.1-46.0), with continuing weight loss and no hypoalbuminemia. CONCLUSIONS: These data suggest that laparoscopic AGB/DS is feasible, with a low morbidity rate. This technique could combine the long-term weight loss of malabsorptive procedures, with a low-morbidity, adjustable, restrictive procedure. This technique could be used in selected patients, but requires a larger study with longer follow-up.

Adult↗
PubMed2003

New developments in gastric bypass procedures and physiological mechanisms.

Since the gastric bypass was first described for weight-reduction surgery almost 50 years ago, a number of remarkable contributions have been made to the field. These advances have led to significant modifications of the technique, evolution of laparoscopic bariatric surgery equipment, and improvement of long-term results. Despite the currently wide-spread practice of laparoscopic bariatric surgery, the precise technique for laparoscopic gastric bypass still varies from institution to institution, and the surgery continues to carry a morbidity rate. Advances in laparoscopic equipment, technology, and our understanding of the pathophysiology behind weight loss, have allowed surgeons to modify the procedure described originally to minimize the morbidity and maximize long-term weight loss. This chapter describes the technique of laparoscopic gastric bypass used at a major academic center that performs over 1000 bariatric procedures each year. In addition, the many recent advances in methodology and pathophysiology are described in detail.

Adaptation, Physiological↗
PubMed2002

Targeted parathyroidectomy in the era of intraoperative parathormone monitoring.

A combination of preoperative localization and intraoperative parathormone (PTH) monitoring permits targeted parathyroidectomy. Multiple approaches have been developed, ranging from unilateral neck exploration (UE) to radio-guided parathyroidectomy (RP) to endoscopic parathyroidectomy (EP). The purpose of this study was to evaluate the efficacy of these approaches in the management of primary hyperparathyroidism. From June 1998 to November 2000 a total of 110 targeted parathyroid operations were performed at a university medical center. All patients underwent technetium-99m-sestamibi scanning, ultrasonography, or both prior to surgery. Intraoperative PTH monitoring was utilized in all cases. Thirty-seven patients underwent UE, 59 underwent RP, and 14 underwent EP. Follow-up ranged from 1 to 24 months. All patients were cured following parathyroidectomy as predicted by a more than 50% reduction of the intraoperative PTH level following removal of all hypersecreting glands. Altogether, 103 patients had a solitary adenoma (95%), and 1 patient had a parathyroid carcinoma. Six patients (5%) had multigland disease, including four cases of hyperplasia and two patients with a double adenoma. Eighty-three patients (75%) were discharged the day of surgery. The use of preoperative localization and intraoperative PTH monitoring permits a targeted approach to the treatment of primary hyperparathyroidism. Endocrine surgeons should be facile in all minimally invasive parathyroid techniques to individualize the operative approach.

Adult↗
PubMed2002

Conversion to a laparoscopic biliopancreatic diversion with a duodenal switch for failed laparoscopic adjustable silicone gastric banding.

BACKGROUND: Initial data indicate that long-term weight loss for patients who have undergone laparoscopic adjustable silicone gastric banding (LASGB) may be inadequate. It is anticipated that many of these patients will require revision in the next few years. The procedure of choice for such a revision is unknown. PATIENTS AND METHODS: Two LASGB patients, who underwent a laparoscopic gastric band removal with a conversion to a biliopancreatic diversion with a duodenal switch (BPD/DS), are presented. RESULTS: Their procedures were completed without intraoperative complications. Significant weight loss over 12 and 13 months was achieved. CONCLUSION: The BPD/DS, as opposed to the Roux-en-Y gastric bypass (RGB), is well suited for LASGB revision, as its proximal anastomosis is at the duodenum, away from the gastric band scar tissue. Our experience performing laparoscopic BPD/DS has yielded satisfactory weight loss results without the need for revision.

Adult↗
PubMed2002

Potential of surgery for curing type 2 diabetes mellitus.

OBJECTIVE: To review the effect of morbid obesity surgery on type 2 diabetes mellitus, and to analyze data that might explain the mechanisms of action of these surgeries and that could answer the question of whether surgery for morbid obesity can represent a cure for type 2 diabetes in nonobese patients as well. SUMMARY BACKGROUND DATA: Diabetes mellitus type 2 affects more than 150 million people worldwide. Although the incidence of complications of type 2 diabetes can be reduced with tight control of hyperglycemia, current therapies do not achieve a cure. Some operations for morbid obesity not only induce significant and lasting weight loss but also lead to improvements in or resolution of comorbid disease states, especially type 2 diabetes. METHODS: The authors reviewed data from the literature to address what is known about the effect of surgery for obesity on glucose metabolism and the endocrine changes that follow this surgery. RESULTS: Series with long-term follow-up show that gastric bypass and biliopancreatic diversion achieve durable normal levels of plasma glucose, plasma insulin, and glycosylated hemoglobin in 80% to 100% of severely obese diabetic patients, usually within days after surgery. Available data show a significant change in the pattern of secretion of gastrointestinal hormones. Case reports have also documented remission of type 2 diabetes in nonmorbidly obese individuals undergoing biliopancreatic diversion for other indications. CONCLUSIONS: Gastric bypass and biliopancreatic diversion seem to achieve control of diabetes as a primary and independent effect, not secondary to the treatment of overweight. Although controlled trials are needed to verify the effectiveness on nonobese individuals, gastric bypass surgery has the potential to change the current concepts of the pathophysiology of type 2 diabetes and, possibly, the management of this disease.

Biliopancreatic Diversion↗
PubMed2002

Hand-assisted laparoscopic donor hepatectomy for living related transplantation in the porcine model.

Use of a minimally invasive approach for donor nephrectomy has proven to be safe and feasible and has increased the pool of donors for living related renal transplantation. A porcine study to assess the safety and feasibility of performing laparoscopic donor hepatectomy was performed, with potential application to human liver donors for living related liver transplantation. Of the 10 50-kg pigs used, 2 underwent an open left lateral segmentectomy to define the pig anatomy. Two subsequent pigs underwent a laparoscopic liver resection to refine the technique. Subsequently, under sterile conditions, six pigs underwent laparoscopic liver resection with use of a hand-assisted technique for long-term study. Diameters and lengths of hepatic vessels and ducts were measured. Operative blood loss, operative time, and warm ischemia duration were noted. Biopsies of the resected specimens were done to look for ischemia. There was one operative death in the group with chronic liver failure, due to stapler misfire and hemorrhage from the left hepatic vein. The only instance of morbidity was a wound infection. The resected liver had minimal warm ischemia time and microscopic changes, which led us to believe that the organ was suitable for transplantation. We believe that this long-term study establishes the feasibility of this procedure.

Alanine Transaminase↗