Don J. Selzer

Comparison of pain and postoperative stress in dogs undergoing natural orifice transluminal endoscopic surgery, laparoscopic, and open oophorectomy

BACKGROUND Few studies are available to compare the potential benefits of natural orifice transluminal endoscopic surgery (NOTES) approaches to traditional surgery. OBJECTIVE To compare complications, surgical stress, and postoperative pain. DESIGN Prospective study in dogs. SETTING Research laboratory. SUBJECTS Thirty dogs. INTERVENTIONS Oophorectomy procedures were performed via NOTES and laparoscopic and traditional open surgery. MAIN OUTCOME MEASUREMENTS Operative time, pain scores, systemic stress parameters (cortisol, glucose), surgical stress markers (interleukin 6, C-reactive protein), 3-day observation. RESULTS Median operative times were 76, 44, and 35 minutes for the NOTES, laparoscopic, and open procedures, respectively, with the NOTES procedure being significantly longer than the other 2 procedures. All ovaries were completely excised, and all the animals survived without complications. The NOTES animals had greater increases in serum cortisol concentrations at 2 hours but no statistically significant differences in glucose concentrations compared with the other groups. Serum interleukin 6 and C-reactive protein concentrations were significantly increased at specific times compared with baseline in the NOTES group, but not in the open or laparoscopic surgery groups. Based on the cumulative pain score and nociceptive thresholds, the animals in the NOTES group demonstrated less evidence of pain. LIMITATIONS Small sample size, limited follow-up. CONCLUSIONS Although the NOTES oophorectomy procedures took approximately twice as long and there may be more evidence of tissue damage as judged by increases in serum cortisol and interleukin 6 concentrations, the dogs in the NOTES group had lower pain scores, especially when compared with animals undergoing open surgery.

Oophorectomy by natural orifice transluminal endoscopic surgery: feasibility study in dogs

BACKGROUND Natural orifice transluminal endoscopic surgery (NOTES) represents a potentially less-invasive alternative to conventional or laparoscopic surgery. OBJECTIVE Our purpose was to develop a canine oophorectomy model for prospective evaluation of intraoperative complications, surgical stress, and postoperative pain and recovery with NOTES. DESIGN Feasibility study. SETTING Academic preclinical research. PATIENTS Ten healthy female dogs. INTERVENTIONS NOTES procedures were performed through gastric access with an electrocautery snare to resect and retrieve the ovaries. The gastrotomy was closed with prototype T-fasteners. MAIN OUTCOME MEASUREMENTS Operative time; complications; postoperative pain scores, and nociceptive threshold; surgical stress markers (interleukin-6 [IL-6], C-reactive protein); systemic stress parameters (cortisol, glucose); necropsy evaluation at 10 to 14 days. RESULTS The mean operative time was 154 minutes (SD +/- 58 minutes) and no animals died as a result of complications from the procedure. The primary difficulty was incomplete ovarian excision and conversion to an open procedure in 1 dog. Serum glucose concentrations increased after surgery and remained elevated for at least 36 hours. The serum cortisol concentration was transiently increased from baseline at 2 hours after surgery. The serum IL-6 concentration peaked at 2 hours after surgery and returned to the baseline value by 18 hours. The serum C-reactive protein concentration increased significantly from baseline, peaked at 12 hours after surgery, and then slowly declined toward baseline but remained elevated at 72 hours after surgery. Nociceptive threshold measurements indicated increased sensitivity to pain for 2 to 24 hours after surgery. At necropsy, surgical sites were healing uneventfully with no significant damage to surrounding organs, no significant growth on bacterial cultures, and no evidence of peritonitis. LIMITATIONS Small number of animals, single center. CONCLUSIONS The NOTES approach to oophorectomy in dogs appears to be a reasonable alternative to traditional surgery. Attention must be paid to ensure complete excision of the ovaries.

Multicenter, prospective, longitudinal study of the recurrence, surgical site infection, and quality of life after contaminated ventral hernia repair using biosynthetic absorbable mesh: The COBRA study

OBJECTIVE The aim of the study was to evaluate biosynthetic absorbable mesh in single-staged contaminated (Centers for Disease Control class II and III) ventral hernia (CVH) repair over 24 months. BACKGROUND CVH has an increased risk of postoperative infection. CVH repair with synthetic or biologic meshes has reported chronic biomaterial infections and high hernia recurrence rates. METHODS Patients with a contaminated or clean-contaminated operative field and a hernia defect at least 9 cm had a biosynthetic mesh (open, sublay, retrorectus, or intraperitoneal) repair with fascial closure (n = 104). Endpoints included overall Kaplan-Meier estimates for hernia recurrence and postoperative wound infection rates at 24 months, and the EQ-5D and Short Form 12 Health Survey (SF-12). Analyses were conducted on the intent-to-treat population, and health outcome measures evaluated using paired t tests. RESULTS Patients had a mean age of 58 years, body mass index of 28 kg/m, 77% had contaminated wounds, and 84% completed 24-months follow-up. Concomitant procedures included fistula takedown (n = 24) or removal of infected previously placed mesh (n = 29). Hernia recurrence rate was 17% (n = 16). At the time of CVH repair, intraperitoneal placement of the biosynthetic mesh significantly increased the risk of recurrences (P ≤ 0.04). Surgical site infections (19/104) led to higher risk of recurrence (P < 0.01). Mean 24-month EQ-5D (index and visual analogue) and SF-12 physical component and mental scores improved from baseline (P < 0.05). CONCLUSIONS In this prospective longitudinal study, biosynthetic absorbable mesh showed efficacy in terms of long-term recurrence and quality of life for CVH repair patients and offers an alternative to biologic and permanent synthetic meshes in these complex situations.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially. http://creativecommons.org/licenses/by-nc-nd/4.0.Objective: The aim of the study was to evaluate biosynthetic absorbable mesh in single-staged contaminated (Centers for Disease Control class II and III) ventral hernia (CVH) repair over 24 months. Background: CVH has an increased risk of postoperative infection. CVH repair with synthetic or biologic meshes has reported chronic biomaterial infections and high hernia recurrence rates. Methods: Patients with a contaminated or clean-contaminated operative field and a hernia defect at least 9 cm2 had a biosynthetic mesh (open, sublay, retrorectus, or intraperitoneal) repair with fascial closure (n = 104). Endpoints included overall Kaplan-Meier estimates for hernia recurrence and postoperative wound infection rates at 24 months, and the EQ-5D and Short Form 12 Health Survey (SF-12). Analyses were conducted on the intent-to-treat population, and health outcome measures evaluated using paired t tests. Results: Patients had a mean age of 58 years, body mass index of 28 kg/m2, 77% had contaminated wounds, and 84% completed 24-months follow-up. Concomitant procedures included fistula takedown (n = 24) or removal of infected previously placed mesh (n = 29). Hernia recurrence rate was 17% (n = 16). At the time of CVH repair, intraperitoneal placement of the biosynthetic mesh significantly increased the risk of recurrences (P ⩽ 0.04). Surgical site infections (19/104) led to higher risk of recurrence (P < 0.01). Mean 24-month EQ-5D (index and visual analogue) and SF-12 physical component and mental scores improved from baseline (P < 0.05). Conclusions: In this prospective longitudinal study, biosynthetic absorbable mesh showed efficacy in terms of long-term recurrence and quality of life for CVH repair patients and offers an alternative to biologic and permanent synthetic meshes in these complex situations.

Evaluation of the Learning Curve for Natural Orifice Transluminal Endoscopic Surgery: Bilateral Ovariectomy in Dogs

OBJECTIVE Study the learning curve for canine Natural Orifice Transluminal Endoscopic Surgery (NOTES) ovariectomy by evaluating operative times and complications. STUDY DESIGN Preclinical research study. ANIMALS Adult female dogs (n=20). METHODS NOTES ovariectomy procedures were performed as follows: Feasibility Group 1 (n=5), Feasibility Group 2 (n=5), and Early Clinical Group 3 (n=10). Six steps of the procedure were identified, timed separately, and the overall time was recorded from introduction to removal of the endoscope. Complications were recorded. Repeated measures analysis of variance using ranked data compared the effect of group (3 levels) on the time for each step. Nonlinear regression using an exponential model with nonzero asymptote was used to model the operative time-procedure number relationship. RESULTS Overall median operative time was significantly longer for Group 1 (195 minutes; range, 160-265 minutes) than Group 2 (108 minutes; range, 81-148 minutes; P=.048) and Group 3 (77 minutes; range, 41-136 minutes; P=.0008). The estimated asymptotic operative time was 71 minutes (95% confidence interval, 41-100 minutes); this time was reached after 10 procedures. Gastric cleansing and removing the left ovary took significantly longer in Group 1 than in Group 2 or 3. Operative complications included incomplete ovarian excision, dropping an ovary during retrieval, and conversion to an open procedure. No intraoperative complications occurred in Group 3. CONCLUSION NOTES procedures result in longer operative times in the early part of the learning curve and require considerable experience before reaching proficiency.

Surgical skills simulation: A shift in the conversation

W ith the publication of the article “State of the Evidence on Simulation-Based Training for Laparoscopic Surgery: A Systematic Review,” Zendejas et al1 have allowed the conversation regarding the skills laboratory and laparoscopic skill acquisition to shift from a discussion of “Is it effective?” to a discussion of “How can it be most effective?” Importantly, this shift in the conversation allows a vigorous focus on critical issues such as the timing to initiate simulation, how best to coordinate the skills laboratory with clinical experience, what type of simulators should be purchased, how to use the skills laboratory to assess proficiency, and how to avoid deterioration of laparoscopic skills. Before these questions are answered, it is necessary to understand why simulation-based training in laparoscopic surgery was inevitable. During the 1990s, a series of events significantly impacted surgical training. In many ways, these changes had a greater impact on surgical training than the often-blamed 80-hour workweek. First, in an attempt to avoid another well-publicized federal lawsuit, medical schools mandated attending surgeon participation in all operative procedures to avoid fraudulent billing activities. Second, the medico-legal environment gave attending surgeons pause as they considered the potential for morbidity associated with autonomous activity of surgical residents. Third, the addition of specialty fellowships reduced the opportunity for surgical residents to participate in new and innovative laparoscopic and endoscopic procedures.2 Fourth, adoption of minimally invasive surgical techniques caused practicing surgeons to reenter the learning curve for operations they had mastered in the traditional open technique. This was most evident as the bile duct injury rate skyrocketed in the early era of laparoscopic cholecystectomy.3 Finally, compared with open surgery, laparoscopic procedures commonly relegate an attending surgeon to camera control and provision of adequate exposure. Consequently, attending surgeons challenged with this less active teaching model limited resident participation in surgical cases further reducing surgical skill acquisition. This combination of stressors caused the responsibility of patient care, surgical decision making, documentation, and performance of surgery to shift to senior residents, fellows, or faculty members. Subsequently, attending surgeons were present for all surgical procedures from start to finish, thus decreasing autonomy and independent learning. Instead, graduating residents were provided with a limited laparoscopic experience and reduced confidence in their ability to enter surgical practice.4,5 In the end, it was clear that a structured curriculum and a better environment for practice were needed to teach these laparoscopic techniques.6 With this publication, Zendejas et al1 have identified the skills laboratory as the appropriate environment for laparoscopic skills acquisition and silenced those who doubt the benefit of simulation-based laparoscopic training.7 Specifically, upon rigorous examination of this pool of more than 200 comparative studies, Zendejas et al1 formulated 3 critical conclusions. First, the authors confirm the superiority of simulation-based laparoscopic training for skill acquisition when compared to intraoperative experience. Even the addition of watching videos of operative procedures prior to operative participation failed to impart laparoscopic skills such as simulation-based training. Second, the authors found that a high price tag did not always result in better training. Systemic analysis of the 21 studies comparing virtual reality (VR) simulators with box trainers failed to demonstrate the superiority of complex virtual reality simulators with haptic feedback. Moreover, as long as the training scenarios resembled the human body, simple box trainers with a webcam or a mirror were as effective as the complex systems. This preference for simpler training devices may also reflect their easier availability, portability, and ease of use. Third, commonly cited as lacking within surgical residencies, Zendejas et al1 found that the opportunity for feedback during the training process was important to overall success with regard to skill acquisition. It seemed clear that feedback of some type generated better outcomes and learner satisfaction, but the best time

Revisional bariatric surgery is more effective for improving obesity-related co-morbidities than it is for reinducing major weight loss.

BACKGROUND Patients having previous bariatric surgery are at risk for weight regain and return of co-morbidities. If an anatomic basis for the failure is identified, many surgeons advocate revision or conversion to a Roux-en-Y gastric bypass. The aim of this study was to determine whether revisional bariatric surgery leads to sufficient weight loss and co-morbidity remission. PATIENTS AND METHODS From 2005-2012, patients undergoing revision were entered into a prospectively maintained database. Perioperative outcomes, including complications, weight loss, and co-morbidity remission, were examined for all patients with a history of a previous vertical banded gastroplasty (VBG) or Roux-en-Y gastric bypass (RYGB). RESULTS Twenty-two patients with a history of RYGB and 56 with a history of VBG were identified. Following the revisional procedure, the RYGB group experienced 35.8% excess weight loss (%EWL) and a 31.8% morbidity rate. For the VBG group, patients experienced a 46.2% %EWL from their weight before the revisional operation with a 51.8% morbidity rate. Co-morbidity remission rate was excellent. Diabetes (VBG:100%, RYGB: 85.7%), gastroesophageal reflux disease (VBG: 94.4%, RYGB: 80%), and hypertension (VBG: 74.2%, RYGB:60%) demonstrated significant improvement. CONCLUSION Revision of a failed RYGB or conversion of a VBG to a RYGB provides less weight loss and a higher complication rate than primary RYGB but provides an excellent opportunity for co-morbidity remission.

Pancreas transplantation after bariatric surgery

Porubsky M, Powelson JA, Selzer DJ, Mujtaba MA, Taber T, Carnes KL, Fridell JA. Pancreas transplantation after bariatric surgery. 
Clin Transplant 2012: 26: E1–E6. 
© 2011 John Wiley & Sons A/S.

Hypertrophic Pyloric Stenosis in an Adolescent

Hypertrophic pyloric stenosis presenting beyond infancy is an uncommon occurrence. The etiology of adult onset pyloric stenosis is unknown. In this case report, we describe a 14-year-old boy who presented with nausea, intermittent vomiting, and abdominal pain. He underwent upper gastrointestinal series, which demonstrated persistent narrowing of the pylorus. He was referred to Pediatric Surgery for evaluation and subsequently underwent laparoscopic pyloroplasty. Postoperatively, the patient did well, and at 20 months, he continues to be asymptomatic.

The burden of incisional hernia in necrotizing pancreatitis: how can we improve?

BACKGROUND Necrotizing pancreatitis (NP) patients frequently require pancreatic debridement, and have risk factors for incisional hernia (IH). However, no published data exist regarding the incidence of IH in NP. The aim of the current study was to define the incidence of and identify risk factors for developing IH after pancreatic debridement. METHODS Hernia presence was determined by clinical examination and patient interview. Technical and clinical considerations were noted: type of incision, closure, suture material, age, body mass index (BMI), diabetes mellitus (DM), preoperative albumin, and number of operations. RESULTS Sixty-three (42%) of 149 debrided patients with NP developed IH. IH patients were older (P<.05). No differences in surgical technique or clinical risk factors were seen between groups. CONCLUSION The incidence of IH in NP patients requiring operative debridement is substantially higher than that in patients undergoing routine laparotomy. Innovative fascial closure techniques such as primary fascial buttress with nonsynthetic mesh should be considered.

Laparoscopic Incisional Hernia Repair After Solid-Organ Transplantation

HYPOTHESIS Laparoscopic incisional hernia repair (LIHR) is efficacious in transplant recipients. DESIGN Retrospective review. SETTING University hospital. PATIENTS Thirty-one transplant recipients who underwent LIHR between July 9, 2004, and October 27, 2005. MAIN OUTCOME MEASURES Operative complications and incisional hernia recurrence. RESULTS The mean (SD) mesh size required for LIHR was 611 (307) cm2. Median (range) hospital stay was 4 (1-28) days, with follow-up of 589 (22-953) days. Eighteen patients developed a postoperative complication, most frequently seroma formation, which occurred in 13 patients (72%). The mesh size required for LIHR was significantly larger in patients with a postoperative complication (n = 18; 706 [319] cm2 vs n = 13; 480 [244] cm2; P = .04). Seroma formation was not associated with previous open hernia repair, diabetes mellitus, or corticosteroid use. No statistically significant relationship was noted between the transplanted organ and seroma development. There were no post-LIHR wound infections. In 7 patients (23%), hernia recurred. CONCLUSIONS Laparoscopic incisional hernia repair in solid-organ transplant recipients is associated with a high rate of seroma formation but minimal long-term morbidity. The recurrence rate after LIHR is equivalent to that after open hernia repair. These results suggest that LIHR is a safe and effective alternative to open repair in this patient population.