Nearly a Third of High-Grade Dysplasia and Colorectal Cancer Is Undetected in Patients with Inflammatory Bowel Disease.

BACKGROUND: It is unclear whether intensive surveillance protocols have resulted in a decreased incidence of colorectal cancer (CRC) in inflammatory bowel disease (IBD). AIMS: To determine the prevalence and characteristics of IBD associated high-grade dysplasia (HGD) or CRC that was undetected on prior colonoscopy. METHODS: This is a single-center, retrospective study from 1994 to 2013. All participants had a confirmed IBD diagnosis and underwent a colectomy with either HGD or CRC found in the colectomy specimen.The undetected group had no HGD or CRC on prior colonoscopies. The detected group had HGD or CRC identified on previous biopsies. RESULTS: Of 70 participants, with ulcerative colitis (UC) (n = 47), Crohn's disease (CD) (n = 21), and indeterminate colitis (n = 2), 29% (n = 20) had undetected HGD/CRC at colectomy (15 HGD and 5 CRC). In the undetected group, 75% had prior LGD, 15% had indefinite dysplasia, and 10% had no dysplasia (HGD was found in colonic strictures). Patients in the undetected group were more likely to have pancolitis (55 vs. 20%) and multifocal dysplasia (35 vs. 8%). The undetected group was less likely to have CRC at colectomy (25 vs. 62%). There was a trend toward right-sided HGD/CRC at colectomy (40 vs. 20%; p = 0.08). In addition, 84% of the lesions found in the rectum at colectomy were not seen on prior colonoscopy in the undetected group. CONCLUSIONS: The prevalence of previously undetected HGD/CRC in IBD found at colectomy was 29%. The high proportion of undetected rectal and right-sided HGD/CRC suggests that these areas may need greater attention during surveillance.

Comparative assessment of physical and cognitive ergonomics associated with robotic and traditional laparoscopic surgeries.

BACKGROUND: We conducted this study to investigate how physical and cognitive ergonomic workloads would differ between robotic and laparoscopic surgeries and whether any ergonomic differences would be related to surgeons' robotic surgery skill level. Our hypothesis is that the unique features in robotic surgery will demonstrate skill-related results both in substantially less physical and cognitive workload and uncompromised task performance. METHODS: Thirteen MIS surgeons were recruited for this institutional review board-approved study and divided into three groups based on their robotic surgery experiences: laparoscopy experts with no robotic experience, novices with no or little robotic experience, and robotic experts. Each participant performed six surgical training tasks using traditional laparoscopy and robotic surgery. Physical workload was assessed by using surface electromyography from eight muscles (biceps, triceps, deltoid, trapezius, flexor carpi ulnaris, extensor digitorum, thenar compartment, and erector spinae). Mental workload assessment was conducted using the NASA-TLX. RESULTS: The cumulative muscular workload (CMW) from the biceps and the flexor carpi ulnaris with robotic surgery was significantly lower than with laparoscopy (p < 0.05). Interestingly, the CMW from the trapezius was significantly higher with robotic surgery than with laparoscopy (p < 0.05), but this difference was only observed in laparoscopic experts (LEs) and robotic surgery novices. NASA-TLX analysis showed that both robotic surgery novices and experts expressed lower global workloads with robotic surgery than with laparoscopy, whereas LEs showed higher global workload with robotic surgery (p > 0.05). Robotic surgery experts and novices had significantly higher performance scores with robotic surgery than with laparoscopy (p < 0.05). CONCLUSIONS: This study demonstrated that the physical and cognitive ergonomics with robotic surgery were significantly less challenging. Additionally, several ergonomic components were skill-related. Robotic experts could benefit the most from the ergonomic advantages in robotic surgery. These results emphasize the need for well-structured training and well-defined ergonomics guidelines to maximize the benefits utilizing the robotic surgery.

Staple versus fibrin glue fixation in laparoscopic total extraperitoneal repair of inguinal hernia: a systematic review and meta-analysis.

BACKGROUND: Fixation of mesh is typically performed to minimize risk of recurrence in laparoscopic inguinal hernia repair. Mesh fixation with staples has been implicated as a cause of chronic inguinal pain. Our study aim is to compare mesh fixation using a fibrin sealant versus staple fixation in laparoscopic inguinal hernia and compare outcomes for hernia recurrence and chronic inguinal pain. METHODS AND PROCEDURES: PubMed was searched through December 2010 by use of specific search terms. Inclusion criteria were laparoscopic total extraperitoneal repair inguinal hernia repair, and comparison of both mesh fibrin glue fixation and mesh staple fixation. Primary outcomes were inguinal hernia recurrence and chronic inguinal pain. Secondary outcomes were operative time, seroma formation, hospital stay, and time to return to normal activity. Pooled odds ratios (OR) were calculated assuming random-effects models. RESULTS: Four studies were included in the review. A total of 662 repairs were included, of which 394 were mesh fixed by staples or tacks, versus 268 with mesh fixed by fibrin glue. There was no difference in inguinal hernia recurrence with fixation of mesh by staples/tacks versus fibrin glue [OR 2.13; 95% confidence interval (CI) 0.60-7.63]. Chronic inguinal pain (at 3 months) incidence was significantly higher with staple/tack fixation (OR 3.25; 95% CI 1.62-6.49). There was no significant difference in operative time, seroma formation, hospital stay, or time to return to normal activities. CONCLUSIONS: The meta-analysis does not show an advantage of staple fixation of mesh over fibrin glue fixation in laparoscopic total extraperitoneal inguinal hernia repair. Because fibrin glue mesh fixation with laparoscopic inguinal hernia repair achieves similar hernia recurrence rates compared with staple/tack fixation, but decreased incidence of chronic inguinal pain, it may be the preferred technique.

Infection during natural orifice transluminal endoscopic surgery: a randomized, controlled study in a live porcine model.

BACKGROUND: Currently reported natural orifice transluminal endoscopic surgery (NOTES) procedures in animals have been done in heterogeneous milieus ranging from nonsterile to sterile procedures, with mixed results, including no infection in those performed in nonsterile settings. OBJECTIVE: To establish the potential frequency of infection during NOTES, comparing sterile to nonsterile approaches. SETTING: Survival experiments on sixteen 50-kg pigs. DESIGN AND INTERVENTIONS: From pilot data (100% infection frequency after nonsterile procedures), sample size (8 animals in each group) was calculated by using a power of 95% and an alpha risk of 0.05. The animals were randomly assigned to two groups: In the transgastric peritoneoscopy study group, liver and ovarian biopsies were performed with sterile overtubes, endoscopes, and accessories and the use of preoperative intravenous antibiotics and antiseptic gastric lavage. In the nonsterile (control) group, the same procedures were performed with nonsterile endoscopes and accessories without the use of gastric lavage and preoperative antibiotics. Complete transmural closure of the transgastric access site was made in all animals. After a 1-week survival time, all animals were killed for necropsy, which included Gram staining and peritoneal cultures. MAIN OUTCOME MEASUREMENTS: Intraperitoneal infection on necropsy. RESULTS: All necropsies revealed intraperitoneal infection (abscesses, fibrinopurulent exudates, and adhesions) in the control group (frequency of infection 100%). Peritoneal bacterial culture grew various aerobic and anaerobic organisms. No gross or bacteriological evidence of infection was seen in the sterile group (frequency of infection 0%, P value = <.0002). LIMITATIONS: Animal experiments. CONCLUSION: Nonsterile conditions invariably lead to intraperitoneal infection. Aseptic techniques during NOTES can prevent intra-abdominal infection. Future studies will determine which infection prevention steps are mandatory and which can be omitted during NOTES procedures.

Gastric wall healing after NOTES procedures: closure with endoscopic clips provides superior histological outcome compared with threaded tags closure.

BACKGROUND: Closure of the transgastric access to the peritoneal cavity is a critical step in natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE: To perform a direct comparison of the histological healing post clips and threaded tags (T-tags) closure after transgastric NOTES procedures. DESIGN AND INTERVENTION: Twelve survival porcine experiments. After standardized endoscopic gastric wall puncture, balloon-dilation, and transgastric peritoneoscopy, closure of the gastric wall was performed with either clips or T-tags. Necropsy at 14 days was performed for histological evaluation of 2-mm interval transversal cross sections of the gastrotomy site. MAIN OUTCOME MEASUREMENTS: Histological healing of the gastric wall opening. RESULTS: Endoscopic closure of the gastrotomy was successfully achieved in all 12 animals, followed by an uneventful 2-week clinical follow-up. Transmural healing was seen in 3 (75%) animals after clip closure compared with only 1 (12.5%) in the group with T-tag closure (P = .06). Gastric wall muscular bridging was observed in 4 (100%) animals with clip closure compared with only 1 (12.5%) in the group with T-tag closure (P = .01). LIMITATIONS: Animal model with short-term follow-up. CONCLUSIONS: Endoscopic clip closure results in a layer-to-layer transmural healing of the gastric wall. In contrast, T-tag gastric wall plication impairs gastric layer bridging. These findings might guide the future design of new endoscopic devices and techniques for gastrotomy closure after NOTES procedures.

A 2-microm continuous-wave laser system for safe and high-precision dissection during NOTES procedures.

INTRODUCTION: Lasers 2-microm in wavelength offer efficient tissue cutting with limited thermal damage in biological tissue. OBJECTIVE: To evaluate the dissection capabilities of a 2-microm continuous-wave laser for NOTES procedures. METHODS AND PROCEDURES: We conducted 18 acute animal experiments. Group 1 (three animals): transcolonic access to the peritoneal cavity (15-W transcolonic laser puncture, balloon dilation over the laser probe). Group 2 (six animals): transcolonic access with needle-knife puncture and balloon dilation. Group 3 (three animals): transgastric access to the peritoneal cavity (similar technique as group 1) followed by laser-assisted dissection of the kidney. In one animal of group 3, a therapeutic target (hematoma) was created by percutaneous puncture of the kidney. Group 4 (six animals): transgastric access (similar to the technique of group 2). RESULTS: Translumenal access to the peritoneal cavity was achieved in 2-3 min in group 1 (significantly shorter than with the needle-knife-assisted technique, 4-5 min, p=0.02) and in 7-10 min in group 3 (compared to 6-17 min in group 4, p=0.88). In group 3, laser dissection of the parietal peritoneum and of perinephric connective tissue allowed access to the retroperitoneum with complete removal of a blood collection in the animal with puncture trauma. Laser dissection demonstrated good maneuverability, clean and rapid cutting, and excellent hemostasis. Peritoneoscopy and necropsy showed no damage of targeted tissue and surrounding organs. CONCLUSIONS: The 2-microm continuous-wave laser system showed promising capabilities for highly precise and safe dissection during NOTES procedures.

Transgastric ventral hernia repair: a controlled study in a live porcine model (with videos).

BACKGROUND: Ventral hernia repair is currently performed via open surgery or laparoscopic approach. OBJECTIVE: To develop an alternative ventral hernia repair technique. SETTING: Acute and survival experiments on twelve 50-kg pigs. DESIGN AND INTERVENTIONS: An endoscope was introduced transgastrically into the peritoneal cavity. An abdominal wall hernia was created through a 5-mm skin incision followed by a 5-cm-long incision of the abdominal wall muscles and aponeurosis. A hernia repair technique was developed in 3 acute experiments. Then animals were randomized into 2 groups. In the experimental group (5 animals) Gore-Tex mesh was transgastrically attached to the abdominal wall, repairing the previously created abdominal wall hernia. In the control group (4 animals), the hernia was not repaired. In both groups, the endoscope was then withdrawn into the stomach, and the gastric wall incision was closed with T-bars. The animals survived for 2 weeks and were then euthanized. MAIN OUTCOME MEASUREMENT: The presence of ventral hernia on necropsy. RESULTS: In the control group, the ventral hernia was present on necropsy in all animals. In the experimental group, the ventral hernia was easily repaired, with no evidence of hernia on necropsy. In the first animal in the experimental group, necropsy revealed infected mesh. After this discovery, we used sterilized cover for mesh delivery and did not find any signs of infection in 4 subsequent study animals. LIMITATION: The study was performed in a porcine model. CONCLUSIONS: Transgastric ventral hernia repair is feasible, technically easy, and effective. It can become a less invasive alternative to the currently used laparoscopic and surgical ventral hernia repair.

Hydrogen leak test is minimally invasive and highly specific for assessment of the integrity of the luminal closure after natural orifice transluminal endoscopic surgery procedures (with video).

BACKGROUND: Leak-resistant closure of transluminal access is a major challenge facing natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE: To evaluate a hydrogen (H(2))-based leak test for assessment of transluminal-access closure integrity after NOTES procedures. SETTING: Nine acute porcine experiments. DESIGN AND INTERVENTION: After gastric-wall puncture and balloon dilation, peritoneoscopy was performed, followed by transmural closure of the gastric opening. The animals were randomly assigned to complete or incomplete closure groups. The H(2) leak test was performed by using 1000 mL of 4% H(2) gas mixture and the Hydrogen Leak Detector H2000+. The animals were then euthanized for a methylene blue (MB) test of gastric closure integrity. MAIN OUTCOME MEASUREMENT: Intraperitoneal H(2) concentration after gastric insufflation with H(2). RESULTS: The H(2) leak test was quick and easy. Intraperitoneal H(2) concentrations in parts per million in both groups were similar at baseline (mean +/- SD, 0.18 +/- 0.29 parts per million [ppm] vs 0.22 +/- 0.35 ppm, P = .97) and after balloon dilation (414.8 +/- 198.5 ppm vs 601.3 +/- 116.1 ppm, P > .99). Postclosure intraperitoneal H(2) concentrations dropped to 0.01 +/- 0.77 ppm in the complete-closure group, similar (P = .81) to matched-pairs preopening levels and significantly lower than in the incomplete-closure group (162.0 +/- 83.0 ppm, P < .02). On necropsy, the MB test was negative in all 5 animals of the complete-closure group and positive in all 4 animals of the incomplete-closure group. A cutoff of 25 ppm in intraperitoneal H(2) concentration after closure gave 100% sensitivity, specificity, and positive and negative predictive values for MB leakage. LIMITATIONS: Nonsurvival animal experiments. CONCLUSIONS: The H(2) leak test is highly accurate for detection of leakage after NOTES procedures and could become a substitute for currently used MB leak tests.

Omentoplasty for gastrotomy closure after natural orifice transluminal endoscopic surgery procedures (with video).

INTRODUCTION: The utility of the greater omentum has not been assessed in transluminal access closure after natural orifice transluminal endoscopic surgery (NOTES) procedures. OBJECTIVE: Our purpose was to evaluate the feasibility, efficacy, and safety of omentoplasty for gastrotomy closure. METHODS AND PROCEDURES: Survival experiments in 9 female 40-kg pigs were randomly assigned to 3 groups: group A, endoscopic full-thickness resection (EFTR) for transgastric access and peritoneoscopy without closure; group B, ETFR and peritoneoscopy with omentoplasty (flap of omentum is pulled into the stomach and attached to the gastric mucosa with clips but no clips are used for gastrotomy closure itself); group C, balloon dilation for opening and peritoneoscopy followed by omentoplasty for closure. The animals were observed for 2 weeks and then underwent endoscopy and necropsy with histologic evaluation. RESULTS: Transgastric opening and peritoneoscopy were achieved in all pigs. In groups B and C, a flap of omentum was easily placed to seal the gastrotomy and then attached to the gastric mucosa with 2 to 5 clips (median 4) in 7 to 20 minutes (median 15 minutes). In group A, peritonitis developed in all animals. In both groups B and C, all animals survived 15 days with no peritonitis and minimal adhesions outside the gastrotomy site. In addition, all achieved complete healing (transmural, n = 4; mucosal ulceration, n = 2) of the gastrotomy site. One animal in group B had an 18-mm abscess in the omental flap. LIMITATIONS: Animal model, small sample size, lack of appropriate controls for group C. CONCLUSIONS: Omentoplasty of the gastrotomy site is a technically feasible method to seal balloon-created transgastric access to the peritoneal cavity after NOTES procedures.

Identification of genes differentially expressed in benign versus malignant thyroid tumors.

PURPOSE: Although fine-needle aspiration biopsy is the most useful diagnostic tool in evaluating a thyroid nodule, preoperative diagnosis of thyroid nodules is frequently imprecise, with up to 30% of fine-needle aspiration biopsy cytology samples reported as "suspicious" or "indeterminate." Therefore, other adjuncts, such as molecular-based diagnostic approaches are needed in the preoperative distinction of these lesions. EXPERIMENTAL DESIGN: In an attempt to identify diagnostic markers for the preoperative distinction of these lesions, we chose to study by microarray analysis the eight different thyroid tumor subtypes that can present a diagnostic challenge to the clinician. RESULTS: Our microarray-based analysis of 94 thyroid tumors identified 75 genes that are differentially expressed between benign and malignant tumor subtypes. Of these, 33 were overexpressed and 42 were underexpressed in malignant compared with benign thyroid tumors. Statistical analysis of these genes, using nearest-neighbor classification, showed a 73% sensitivity and 82% specificity in predicting malignancy. Real-time reverse transcription-PCR validation for 12 of these genes was confirmatory. Western blot and immunohistochemical analyses of one of the genes, high mobility group AT-hook 2, further validated the microarray and real-time reverse transcription-PCR data. CONCLUSIONS: Our results suggest that these 12 genes could be useful in the development of a panel of markers to differentiate benign from malignant tumors and thus serve as an important first step in solving the clinical problem associated with suspicious thyroid lesions.

Air and fluid leak tests after NOTES procedures: a pilot study in a live porcine model (with videos).

BACKGROUND: Transluminal access site closure remains a major challenge in natural orifice transluminal endoscopic surgery (NOTES). OBJECTIVE: Our purpose was to develop in vivo leak tests for evaluation of the integrity of transgastric access closure. SETTINGS: Survival experiments on 12 50-kg pigs. DESIGN AND INTERVENTIONS: After a standardized transgastric approach to the peritoneal cavity and peritoneoscopy, the gastric wall incision was closed with T-bars (Wilson-Cook Medical, Winston-Salem, NC) deployed on both sides of the incision and then cinched together. Gastrotomy closure was assessed with air and fluid leak tests. The animals were observed for 1 week and then underwent endoscopic evaluation and necropsy. MAIN OUTCOME MEASUREMENTS: (1) Leak-proof closure of the gastric wall incision. (2) Gastric incision healing 1 week after the procedure. RESULTS: The mean intraperitoneal pressure increased 10.7 +/- 3.7 mm Hg during gastric insufflation when the air leak test was performed before closure compared with 0.9 +/- 0.8 mm Hg after transmural closure of the transgastric access site with T-bars (P < .001). Fluid leak tests demonstrated no leakage of liquid contrast from the stomach into the peritoneal cavity after closure. Necropsy in 1 week confirmed completeness of the gastric closure in all animals with full-thickness healing and no spillage of the gastric contents into the peritoneal cavity. LIMITATIONS: Leak tests were only evaluated on an animal model. CONCLUSIONS: Fluid and air leak tests are simple techniques to evaluate in vivo the adequacy of the transluminal access site closure after NOTES procedures. Leak-proof gastric closure resulted in adequate tissue approximation and full-thickness healing of the gastric wall incision.

Peritoneal acidosis mediates immunoprotection in laparoscopic surgery.

BACKGROUND: We have shown previously that abdominal insufflation with CO(2) increases serum levels of IL-10 and TNFalpha and increases survival among animals with lipopolysaccharide (LPS)-induced sepsis, even after a laparotomy. We demonstrated previously that the effect of CO(2) is not from changes in systemic pH, although the peritoneum is locally acidotic during abdominal insufflation with CO(2) even when systemic pH is corrected. We hypothesized that acidification of the peritoneum via means other than CO(2) insufflation would produce alterations in the inflammatory response similar to those associated with CO(2) pneumoperitoneum. METHODS: In total, 42 rats were randomized into 7 groups (n = 6): 1) LPS only, 2) anesthesia control, 3) helium pneumoperitoneum, 4) CO(2) pneumoperitoneum, 5) buffered mild acid lavage, 6) buffered strong acid lavage, and 7) buffered strong acid lavage + helium pneumoperitoneum. Animals received anesthesia with vaporized isoflurane (except the LPS-only group) and their respective abdominal treatment (pneumoperitoneum and/or lavage) for 30 min followed immediately by stimulation with systemic LPS (1 mg/kg, IV). Blood was harvested via cardiac puncture 60 min after LPS injection, and serum levels of IL-10 and TNFalpha levels were determined by enzyme-linked immunosorbent assay. RESULTS: Mean peritoneal pH decreased (P < .05) after CO(2) pneumoperitoneum, buffered strong acid lavage, and buffered strong acid lavage + helium pneumoperitoneum, and it decreased (P = .1) after helium pneumoperitoneum alone and buffered mild acid lavage. IL-10 levels were increased (P < .01), and TNFalpha levels decreased (P < .001) among animals with acidic peritoneal cavities compared with animals with pH-normal peritoneal cavities. Decreasing peritoneal pH correlated with both increasing IL-10 levels (r = -.465, P < .01) and decreasing TNFalpha levels (r = 0.448, P < .01). Among animals with peritoneal acidosis, there were no differences in levels of IL-10 or TNFalpha regardless of insufflation status (P > .05 for both cytokines). CONCLUSIONS: Acidification of the peritoneal cavity whether by abdominal insufflation or by peritoneal acid lavage increases serum IL-10 and decreases serum TNFalpha levels in response to systemic LPS challenge. The degree of peritoneal acidification correlates with the degree of inflammatory response reduction. These results support the hypothesis that pneumoperitoneum-mediated attenuation of the inflammatory response after laparoscopic surgery occurs via a mechanism of peritoneal cell acidification.

CO2 abdominal insufflation pretreatment increases survival after a lipopolysaccharide-contaminated laparotomy.

Carbon dioxide (CO(2))-pneumoperitoneum is known to favorably modify the systemic immune response during laparoscopic surgery. The presented studies were designed to determine whether treating animals with CO(2) abdominal insufflation before undergoing a lipopolysaccharide (LPS)-contaminated laparotomy would serve as "shock prophylaxis" and thus improve survival and attenuate cytokine production. Rats were randomized into five groups: CO(2)-pneumoperitoneum, helium-pneumoperitoneum, anesthesia control, laparotomy/LPS control, and LPS only control. Animals in the first four groups all received a laparotomy and a lethal dose of LPS. Immediately preceding their laparotomy, animals in the pneumoperitoneum groups received a 30-minute pretreatment of abdominal insufflation with either CO(2) or helium. The anesthesia control group received a 30-minute pretreatment of isoflurane. Animal mortality was then recorded during the ensuing 72 hours. Subsequently, a similar protocol was repeated for measurements of cytokines. CO(2)-pneumoperitoneum increased survival at 48 hours compared with LPS control (P <.05), and decreased interleukin-6 plasma levels at 2 hours (P <.05). Abdominal insufflation with CO(2) before the performance of a laparotomy contaminated with endotoxin increases survival and attenuates interleukin-6. The beneficial immune-modulating effects of CO(2)-pneumoperitoneum endure after abdominal insufflation. CO(2)-pneumoperitoneum pretreatment may improve outcomes among patients undergoing gastrointestinal surgery who are at high risk for abdominal fecal contamination.

Does pancreatic duct stenting decrease the rate of pancreatic fistula following pancreaticoduodenectomy? Results of a prospective randomized trial.

Pancreatic duct stenting remains an attractive strategy to reduce the incidence of pancreatic fistulas following pancreaticoduodenectomy (PD) with encouraging results in both retrospective and prospective studies. We performed a prospective randomized trial to test the hypothesis that internal pancreatic duct stenting reduces the development of pancreatic fistulas following PD. Two hundred thirty-eight patients were randomized to either receive a pancreatic stent (S) or no stent (NS), and stratified according to the texture of the pancreatic remnant (soft/normal versus hard). Four patients were excluded from the study; in three instances due to a pancreatic duct that was too small to cannulate and in the other instance because a total pancreatectomy was performed. Patients who randomized to the S group had a 6-cm-long segment of a plastic pediatric feeding tube used to stent the pancreaticojejunostomy anastomosis. In patients with a soft pancreas, 57 randomized to the S group and 56 randomized to the NS group. In patients with a hard pancreas, 58 randomized to the S group and 63 randomized to the NS group. The S and NS groups for the entire study population, as well as for the subgroup of high-risk patients with soft pancreata, were similar as regard to demographics, past medical history, preoperative symptoms, preoperative procedures, and intraoperative data. The pancreatic fistula rate for the entire study population was 9.4%. The fistula rates in the S and NS subgroups with hard pancreata were similar, at 1.7% and 4.8% (P = 0.4), respectively. The fistula rates in the S and NS subgroups with soft pancreata were also similar, at 21.1% and 10.7% (P = 0.1), respectively. A nonstatistically significant increase in the pancreatic fistula rate in the S group persisted after adjusting for the operating surgeon and technical details of the operation (e.g., anastomotic technique, anastomotic orientation, pancreatic duct size, and number of intra-abdominal drains placed). In patients with soft pancreata, 63% percent of the pancreatic fistulas in stented patients required adjustment to the clinical pathway (including two deaths), compared to 47% of the pancreatic fistulas in patients in the NS group (P = 0.3). Internal pancreatic duct stenting does not decrease the frequency or the severity of postoperative pancreatic fistulas.

Laparoscopic resection of a paraganglioma of the organ of Zuckerkandl in a patient with a carotid body tumor.

Paragangliomas of the organ of Zuckerkandl are rare tumors with only several case reports noted in the literature. Synchronous paraganglioma occur sporadically, and on occasion, in association with several genetic syndromes. Paraganglioma of the organ of Zuckerkandl with synchronous carotid body paraganglioma is described herein. Traditionally, surgical resection of abdominal paraganglioma involved an exploratory laparotomy. In this manuscript, we describe one of the first reported laparoscopic resections of this tumor and review the literature on multiple paragangliomas and their associated genetic syndromes.

Carbon dioxide pneumoperitoneum-mediated attenuation of the inflammatory response is independent of systemic acidosis.

BACKGROUND: The purpose of this study was to determine if systemic acidosis induced by peritoneal absorption of carbon dioxide (CO2 ) during laparoscopy plays a role in CO2 pneumoperitoneum-mediated attenuation of the acute phase inflammatory response associated with perioperative sepsis. The influence of hepatic polymorphonuclear (PMN) leukocyte infiltration on this phenomenon was also investigated. METHODS: Forty-five rats were randomized into 5 groups: anesthesia control, open cecal ligation and puncture (OCLP), laparoscopic cecal ligation and puncture using helium for insufflation (He LCLP), LCLP using CO2 with continued spontaneous ventilation (LCLP-SV), and LCLP using CO2 with intubation and positive pressure ventilation (LCLP-PPV). RESULTS: After 30 minutes, arterial blood gas parameters remained normal in control, OCLP rats, and He LCLP rats, while CO2 LCLP-SV rats developed significant hypercarbic acidosis. This acidosis was corrected in CO2 LCLP-PPV rats ( P < .0001 vs CO2 LCLP-SV for both). Expression of the rat acute phase gene alpha 2 -macroglobulin was greater after OCLP and He LCLP than after either CO2 LCLP-SV or CO2 LCLP-PPV ( P < .0001 vs either CO2 OCLP-SV for both). However, levels of alpha 2 -macroglobulin were not significantly different between the acidotic (LCLP-SV) and normocarbic (LCLP-PPV) CO2 groups. Infiltration of the hepatic parenchyma by PMNs did not differ significantly between groups. CONCLUSIONS: CO2 insufflation-induced systemic acidosis is not responsible for the reduction in the acute phase inflammatory response observed in laparoscopic animal models of sepsis. Hepatic PMN infiltration also does not appear to mediate this effect.

Laparoscopic total abdominal colectomy in the acute setting.

We report results from a single surgeon's 10-year team experience with laparoscopic total abdominal colectomy. We review our series, which includes a large subgroup of ill, high-risk patients with acute colitis requiring urgent surgery. From 1993 to 2003, we performed 65 laparoscopic total abdominal colectomies. All patients referred for total abdominal colectomy were offered the laparoscopic approach. We prospectively collected the following data on all patients: demographics, surgical indications, preoperative status, duration of surgery, intraoperative blood loss, operative complications, length of stay, subsequent operations, patient satisfaction, and lessons learned from our team experience. Preoperative diagnoses included ulcerative colitis (n=55), Crohn's colitis (n=3), colonic inertia (n=4), and familial adenomatous polyposis (n=3). Among the patients with inflammatory bowel disease, 70% of cases were performed on ill patients, refractory to medical management, requiring urgent surgery. This subgroup was managed with laparoscopic total abdominal colectomy and Brooke ileostomy, with ileoanal pouch anastomosis deferred. Operative times were long, ranging from 6 to 11 hours. Mean intraoperative blood loss was 200 ml. Mean length of stay was 4.3 days and ranged from 2 to 13 days. There were no conversions to open surgery and there were no deaths. Complications occurred in 12% of patients and included intra-abdominal abscess (n=2), wound infection (n=3), stoma stenosis (n=1), and incisional hernia (n=2). Postoperative patient satisfaction was high. Subsequent operations, including restorative proctectomy, were also performed laparoscopically. Laparoscopic total abdominal colectomy is technically challenging and requires a team approach but offers patients significant benefit in length of stay and surgical recovery. This operation can be effectively used with minimal morbidity in difficult, ill patients requiring urgent surgery.

Abdominal insufflation with CO2 causes peritoneal acidosis independent of systemic pH.

We have shown that the inflammation-attenuating effects of CO(2) pneumoperitoneum during laparoscopy are not due to changes in systemic pH. However, acidification of peritoneal macrophages in an in vitro CO(2) environment has been shown to reduce LPS-mediated cytokine release. We tested the hypothesis that the peritoneum is locally acidotic during abdominal insufflation with CO(2)--even when systemic pH is corrected. Rats (n = 20) were anesthetized and randomized into two groups: continued spontaneous ventilation (SV) or intubation and mechanical ventilation (MV). All animals were then subjected to abdominal insufflation with CO(2). Mean arterial pH among SV rats decreased significantly from baseline after 15 and 30 minutes of CO(2) pneumoperitoneum (7.329 --> 7.210 --> 7.191, P < 0.05), while arterial pH among MV rats remained relatively constant (7.388 --> 7.245 --> 7.316, P = NS). In contrast, peritoneal pH dropped significantly from baseline and remained low for both groups during CO(2) abdominal insufflation (SV 6.74 --> 6.41 --> 6.40, P < 0.05; MV 6.94 --> 6.45 --> 6.45, P < 0.05). In a second experiment, rats (n = 10) were randomized to receive abdominal insufflation with either CO(2) or helium. Abdominal insufflation with helium did not significantly affect peritoneal pH (7.10 --> 7.02 --> 6.95, P = NS), and the decrease in pH among CO(2)-insufflated animals was significant compared with helium-insufflated animals (P < 0.05). Peritoneal pH returned to baseline levels in all groups within 15 minutes of desufflation in both experiments. A significant local peritoneal acidosis occurs during laparoscopy which is specifically attributable to the use of CO(2) and which is independent of systemic pH. These data provide additional evidence that localized peritoneal acidosis is central to the mechanism of CO(2)-mediated attenuation of the inflammatory response following laparoscopic surgery.

Long-term quality of life and risk factors for recurrence after laparoscopic repair of paraesophageal hernia.

IMPORTANCE: Laparoscopic repair of paraesophageal hernia (PEH) has been shown to result in excellent relief of symptoms and improved quality of life (QOL) despite a relatively high radiographically identified recurrence rate. OBJECTIVE: To assess potential risk factors for recurrence and long-term change in QOL after laparoscopic repair of PEH. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective study of 111 patients who underwent elective laparoscopic repair of type III PEH with biological mesh buttressed over a primary cruroplasty from April 3, 2009, through July 31, 2014, at the Department of Surgery, Johns Hopkins University of Medicine. We administered a modified version of a validated gastroesophageal reflux disease-specific QOL tool to patients before and at 2, 12, and 36 months after the procedure. Higher QOL scores represent greater severity of symptoms. An upper gastrointestinal tract barium-contrast radiographic examination was performed at 1 year to assess for recurrence. Demographic factors, comorbidities, and preoperative radiographic findings were analyzed as possible indicators for recurrence using logistic regression. MAIN OUTCOMES AND MEASURES: Quality of life, measured by the gastroesophageal reflux disease-specific QOL tool, and recurrence, defined as a PEH of greater than 2 cm. RESULTS: Median patient age was 61 years, 63.1% of patients were women, and 81.1% of patients were white. Four patients required reoperation, of which only 1 was for symptomatic recurrent PEH. The mean follow-up time for the 36-month QOL assessment was 43.5 months. The overall preoperative and 2-, 12-, and 36-month QOL scores were 28.50, 10.18, 9.74, and 10.58, respectively (P < .001). Recurrences were found in 19 of the 70 patients (27%) who completed the 1-year radiographic examination. Compared with baseline, all individual symptoms improved significantly except for early satiety (mean [SD] score, 3.18 [1.88] at baseline vs 2.07 [1.70] at the 36-month follow-up; P = .07), nausea (1.69 [1.63] vs 0.77 [1.25]; P = .08), pain with swallowing (1.06 [1.50] vs 0.53 [0.90]; P = .73), and bloating/gas (3.28 [1.71] vs 2.23 [1.72]; P = .05) at the 36-month QOL assessment. Although not statistically significant, preoperative hernias containing most of the stomach were more likely to recur after repair when compared with those involving gastric cardia and fundus (odds ratio, 3.74 [95% CI, 0.93-15.14]; P = .06). CONCLUSIONS AND RELEVANCE: Overall, laparoscopic repair of PEH with biological mesh results in excellent long-term QOL. The cause of recurrence is likely multifactorial and individualized to each patient. Further evaluation of novel techniques and unidentified patient factors is needed.