Long-term behavioral assessment of guinea pigs following neonatal pneumoperitoneum.

BACKGROUND: Using guinea pigs, we previously demonstrated that pneumoperitoneum during pregnancy produces behavioral deficits in the offspring. In the current study, the purpose was to determine if CO(2) pneumoperitoneum during the early postnatal period also produced behavioral anomalies. METHODS: Following delivery, guinea pig pups were randomly assigned to one of three treatment groups: CO(2) pneumoperitoneum (P), laparotomy (L), or isolation control (I). Surgeries were performed on postnatal day (PND) 5 under isoflurane anesthesia; control pups were isolated from the dams for an equivalent period of time. On PNDs 10, 20, 40, and 60, behavior was assessed by monitoring locomotor and exploratory activity. RESULTS: A total of 29 animals were studied. We observed no immediate morbidity or mortality and the manipulations did not appear to affect postnatal growth. On PND 10, pups in group P exhibited lower levels of locomotor activity compared to L and I neonates, but this difference resolved as the animals got older. Histologic assessment of the adult offspring brains revealed no evidence of neurologic injury. CONCLUSION: These data suggest that unlike insufflation during pregnancy, neonatal pneumoperitoneum does not produce behavioral deficits.

Laparoscopic adrenalectomy for pheochromocytoma. A comparison to aldosteronoma and incidentaloma.

BACKGROUND: Laparoscopic adrenalectomy is a safe and effective treatment for most surgical diseases of the adrenal gland. However it has been suggested that catecholamine effects associated with pheochromocytoma render the laparoscopic approach a more challenging and a more morbid procedure. The purpose of this study was to compare the operative characteristics and outcomes of laparoscopic adrenalectomy for pheochromocytoma to those of aldosteronoma and incidentaloma. METHOD: Patient records and operative reports were retrospectively reviewed for demographics, diagnoses, operative management, and outcomes for patients undergoing laparoscopic adrenalectomy between June 1994 and July 2002 at two academic medical centers. A total of 74 patients were included and analyzed by diagnosis. Differences were considered statistically significant at p < 0.05. RESULTS: Twenty-eight patients with pheochromocytoma, 27 with aldosteronoma, and 19 with incidentally discovered nonfunctioning adrenal masses underwent laparascopic adrenalectomy. Patients undergoing resection for pheochromocytoma trended toward more operative blood loss (150 ml) compared to aldosteronoma (88 ml) and incidentaloma (75 ml). Eight patients were converted to an open procedure for a 10.8% conversion rate. The mean operative time was 171 min and there was a 10.8% perioperative complication rate. The mean hospital stay was 3.4 days. These results were not statistically significant between diagnostic groups. CONCLUSION: Despite concern about increased operative times and morbidity associated with pheochromocytoma, our experience supports that laparoscopic adrenalectomy may be performed as safely as, and achieve outcomes similar to, those for other diseases.

Early postnatal behavior deficits after maternal carbon dioxide pneumoperitoneum during pregnancy.

BACKGROUND: In this study, we tested the hypothesis that maternal pneumoperitoneum produces early postnatal behavior deficits in the offspring. METHODS: Time-dated pregnant guinea pigs were exposed to 45 min of carbon dioxide (CO2) pneumoperitoneum at a pressure of 7 mmHg. There was no manipulation of the control animals. On postnatal days (PND) 10 and 20, the behavior of their offspring was assessed by monitoring the locomotor activity of each of the pups in a 1 x 1 m chamber demarcated into 100 squares. Locomotor data was log-transformed and expressed as mean values (SD). RESULTS: At PND 10, pneumoperitoneum offspring exhibited significantly higher levels of locomotor activity than the offspring of controls (1.81 +/- 0.48 vs 1.33 +/- 0.78). The pneumoperitoneum pups continued to exhibit hyperactive behavior at PND 20 (1.83 +/- 0.72 vs 1.20 +/- 0.72). CONCLUSIONS: Maternal pneumoperitoneum produces postnatal hyperactivity in guinea pig offspring, suggesting that there may be long-term consequences associated with the physiologic changes produced in the fetus during CO2 insufflation.

A canine model of gastroesophageal reflux disease (GERD).

BACKGROUND: Although a variety of antireflux procedures and medications are used to treat gastroesophageal reflux disease (GERD), reliable large-animal models of GERD that can be used to objectively compare the efficacy of these treatments are lacking. METHODS: Esophageal manometry and 24-h gastroesophageal pH monitoring with event data were performed in 18 mongrel dogs with a cervical esophagopexy. We then calculated a modified DeMeester score: The Duke Canine reflux score (DCR). Thereafter, the animals underwent a 4-cm anterior distal esophageal myotomy, incision of the left diaphragmatic crus, and intrathoracic gastric cardiopexy. Postoperative 24-h pH and manometry were obtained 2 weeks later. RESULTS: The postoperative 24-h pH results showed a significant increase in the mean DCR score (5.9 +/- 4.5 vs 84.9 +/- 56.1, p < 0.0002), and manometry indicated a significant decrease in mean lower esophageal sphincter (LES) pressure (7.1 +/- 2.9 vs 3.2 +/- 2.5 mmHg, p < 0.0001). CONCLUSION: This technique reliably creates a canine model of GERD.

The need for training opportunities in advanced laparoscopic surgery.

BACKGROUND: There is controversy regarding the amount of training necessary to safely perform advanced laparoscopic surgery. General surgical residency often provides only a low volume of advanced laparoscopic cases and there is growing interest in nonaccredited fellowships focused on laparoscopic surgery. OBJECTIVE: To assess surgical residents' perception of the need for training in advanced laparoscopic surgery in addition to that provided in a standard general surgical residency. METHODS: A 15-item questionnaire was mailed to 985 physicians who either were Society of American Gastrointestinal Endoscopic Surgeons (SAGES) candidate members or had attended a SAGES resident course in 1998 or 1999. For the purposes of the survey, laparoscopic Nissen fundoplication, laparoscopic herniorrhaphy, laparoscopic splenectomy, and laparoscopic colectomy were chosen as advanced procedures. RESULTS: Of the 85 responses obtained, 81% were from respondents who were at the postgraduate fourth-year (PG4) level or higher. Furthermore, 58% of the respondents had taken a course in advanced laparoscopic surgery outside their residency program. The respondents believed that to perform the procedures safely and with confidence on entering practice, they needed to do at least eight each of the selected laparoscopic procedures. As reported, 45% of the respondents had performed three or fewer laparoscopic hernias; 60% had performed three or fewer laparoscopic Nissen fundoplications; 81% had performed three or fewer laparoscopic colectomies; and 86% had performed three or fewer splenectomies. Only 32% of the residents expected to perform more than 10 laparoscopic Nissen fundoplications, only 10% expected to perform more than 10 colectomies, and only 4% expected to perform more than 10 splenectomies before completing their residency. Many respondents (65%) said they would pursue an additional year of advanced laparoscopic training if it were available. In programs unaffiliated with a fellowship in advanced laparoscopic surgery, 65% of the residents were concerned that such a fellowship would interfere with residency training in laparoscopic surgery. In comparison, only 24% of the residents in programs affiliated with a fellowship in advanced laparoscopic surgery believed that the fellowship interfered with their training, whereas 47% of the residents in programs affiliated with a fellowship in advanced laparoscopic surgery thought that the fellowship had no impact on their training. CONCLUSIONS: Residents clearly perceive a need for additional training in advanced laparoscopic surgery. Residents from programs without a laparoscopic fellowship are concerned about a negative impact on their experience from a laparoscopic fellow, but residents from programs with a laparoscopic fellowship are neutral about the impact of a fellow.

Helical CT cholangiography with three-dimensional volume rendering using an oral biliary contrast agent: feasibility of a novel technique.

OBJECTIVE: We evaluated the feasibility and image quality of a new noninvasive biliary imaging technique: helical CT cholangiography with three-dimensional volume rendering using an oral biliary contrast agent. SUBJECTS AND METHODS: Nineteen subjects including five healthy volunteers and 14 patients underwent helical CT cholangiography. Subjects ingested 6.0 g of iopanoic acid 6-10 hr before undergoing imaging. Axial data were used to construct three-dimensional volume-rendered cholangiograms. Two radiologists, an endoscopist, and a laparoscopic surgeon reviewed the images and evaluated overall image quality. In the 14 patients, findings from CT cholangiography were compared with those from ERCP, surgery, and intraoperative cholangiography. RESULTS: All segments of the biliary tree were opacified in all volunteers except one, in whom the intrahepatic ducts were not opacified. Image quality was good to excellent in all volunteers. Anomalous cystic duct insertions were seen in two volunteers. Opacification of the biliary tree was rated as acceptable to excellent in nine patients and suboptimal in five. In five patients with good or excellent opacification, the biliary anatomy correlated with findings on intraoperative cholangiography or ERCP. CT cholangiography revealed additional conditions (gallbladder varices and acute pancreatitis) and variant anatomy in three patients. CONCLUSION: Results of this pilot project suggest that obtaining CT cholangiograms using an oral biliary contrast agent is a feasible, noninvasive method for revealing biliary anatomy. However, visualization of the biliary tree was suboptimal in 36% of the patients, which represents a limitation of this technique.

Intraperitoneal immunity and pneumoperitoneum.

BACKGROUND: Carbon dioxide (CO(2)) pneumoperitoneum has been implicated as a possible factor in depressed intraperitoneal immunity. Using in vitro functional assays, CO(2) has been shown to decrease the function of peritoneal macrophages harvested from insufflated mice. However, an effective in vivo assessment is lacking. Listeria monocytogenes (LM), an intracellular pathogen, has served as a well-established in vivo model to study cell-mediated immune responses in mice. This study examines the immune competence of mice based on their ability to clear intraperitoneally administered LM following CO(2) vs helium (He) insufflation. METHODS: Eighty-five mice (C57Bl/6, males, 4-6 weeks old) were divided between the following four treatment groups: CO(2) insufflation, He insufflation, abdominal laparotomy (Lap), and control (anesthesia only). Immediately postoperatively, each group was inoculated percutaneously and intraperitoneally with a sublethal dose (.015 x 10(6) org) of virulent LM (EGD strain). Half of the animals were killed on postoperative day 3 and half on day 5. Spleens and livers (sites of bacterial predilection) were harvested, homogenized, and plated on TSB agar. The amount of bacteria (1 x 10(6) LM/spleen and liver) from each group was then compared. Statistical significance was set at p

Laparoscopy and mesothelioma.

Malignant mesothelioma is a well-recognized long-term sequela of chronic asbestos exposure. Asbestos use in the United States began in the 1950s and was widespread until the mid-1970s. Although currently only 2.2 cases per million population per year are diagnosed, disease incidence is increasing because of the long latency of this neoplasm. A latency of 15-50 years means that a higher incidence of this neoplasm can be anticipated in the future. The authors report a patient with peritoneal mesothelioma and no known prior exposure to asbestos. The diagnosis was confirmed by exploratory laparoscopy, which entailed biopsies of the diaphragm and of the peritoneal and abdominal walls, and by cytologic evaluation of 700 ml ascitis fluid. At present, exploratory laparoscopy offers the quickest, safest, and least invasive way to confirm the clinical diagnosis of peritoneal malignant mesothelioma.

Conversion factors for laparoscopic splenectomy for immune thrombocytopenic purpura.

BACKGROUND: Since 1994, 27 patients at our institution have undergone laparoscopic splenectomy for immune thrombocytopenic purpura (ITP). Laparoscopic splenectomy was completed in 22 of these patients. We sought to identify factors that precluded successful laparoscopic splenectomy in the remaining 5 patients. METHODS: Retrospective review of 27 patients with ITP undergoing laparoscopic splenectomy was performed at Duke University Medical Center from August, 1994 to September, 1997. RESULTS: Laparoscopic splenectomy was performed in 16 women and 11 men with a mean age of 47.2 years. Five (18%) of these procedures were converted to open splenectomy. There was no significant difference in age, ASA score, gender, weight, height, or splenic size between the converted and laparoscopic groups. However, preoperative and postoperative platelet counts were significantly higher in the laparoscopic group than in the converted group (p < 0.001). Operative times also were significantly longer for the laparoscopic group than for the converted group (p < 0.001). Adherent adjacent structures, associated comorbidities, and technical errors prohibited laparoscopic completion in five patients. Technical errors with subsequent bleeding required conversion in two patients. A thickened greater omentum blanketing the splenic capsule and a densely adherent pancreatic tail extending well into the splenic hilum prevented laparoscopic completion in two patients. Increased peak airway pressures greater than 60 mmHg after pneumoperitoneum necessitated conversion in the remaining patient, who had a previous history of pulmonary insufficiency. Regardless of surgical approach, all patients achieved a therapeutic response after splenectomy. Splenectomies completed laparoscopically resulted in a significantly shorter length of hospital stay (p < 0.01). CONCLUSIONS: Densely adherent adjacent structures, technical errors, and cardiopulmonary instability may preclude successful completion of laparoscopic splenectomies. Thorough preoperative evaluation with an emphasis on the cardiopulmonary system may elicit a cohort of individuals with ITP who are unlikely to undergo laparoscopic splenectomy successfully. This cohort also may include individuals with preoperative platelet counts less than 35,000 mm(-3).

Unusual complications following laparoscopic Nissen fundoplication.

Laparoscopic Nissen fundoplication is commonly used to treat medically refractory gastroesophageal reflux disease. The most frequent severe complications following laparoscopic Nissen fundoplication are pneumothorax, gastroesophageal leak, and splenic injury. Prompt recognition and treatment of complications are important in reducing subsequent morbidity and mortality. This report describes two postoperative complications: (1) delayed diagnosis of a postoperative gastric perforation despite an unrevealing work-up for postoperative fever and abdominal pain; and (2) postoperative pancreatitis following revision of a fundoplication.

Pseudo-Mirizzi syndrome in acute cholecystitis.

Common hepatic duct obstruction secondary to an impacted cystic duct stone is commonly referred to as the Mirizzi syndrome. Mirizzi syndrome is an uncommon cause of obstructive jaundice and can be mimicked by several other rare conditions. We describe a patient with a massively distended gallbladder due to acute cholecystitis who presented with clinical and cholangiographic findings simulating the Mirizzi syndrome. Endoscopists should be aware of acute cholecystitis as a possible etiology of common hepatic duct obstruction.