Preliminary pneumoperitoneum facilitates transgastric access into the peritoneal cavity for natural orifice transluminal endoscopic surgery: a pilot study in a live porcine model.

BACKGROUND AND STUDY AIMS: Safe entrance into the peritoneal cavity through the gastric wall is paramount for the successful clinical introduction of natural orifice transluminal endoscopic surgery (NOTES). The aim of the study was to develop alternative safe transgastric access to the peritoneal cavity. PATIENTS AND METHODS: We performed 11 survival experiments on 50-kg pigs. In sterile conditions, the abdominal wall was punctured with a Veress needle. The peritoneal cavity was insufflated with 2 L carbon dioxide (CO (2)). A sterile endoscope was introduced into the stomach through a sterile overtube; the gastric wall was punctured with a needle-knife; after balloon dilation of the puncture site, the endoscope was advanced into the peritoneal cavity. Peritoneoscopy with biopsies from abdominal wall, liver and omentum, was performed. The endoscope was withdrawn into the stomach. The animals were kept alive for 2 weeks and repeat endoscopy was followed by necropsy. RESULTS: The pneumoperitoneum, easily created with the Veress needle, lifted the abdominal wall and made a CO (2)-filled space between the stomach and adjacent organs, facilitating gastric wall puncture and advancement of the endoscope into the peritoneal cavity. There were no hemodynamic changes or immediate or delayed complications related to pneumoperitoneum, transgastric access, or intraperitoneal manipulations. Follow-up endoscopy and necropsy revealed no problems or complications inside the stomach or peritoneal cavity. CONCLUSIONS: Creation of a preliminary pneumoperitoneum with a Veress needle facilitates gastric wall puncture and entrance into the peritoneal cavity without injury to adjacent organs, and can improve the safety of NOTES.

Peroral transgastric endoscopic primary repair of a ventral hernia in a porcine model.

BACKGROUND AND STUDY AIMS: Multiple studies have demonstrated the feasibility of peroral transgastric endoscopic procedures in animal models. The aim of the study was to evaluate the feasibility of a peroral transgastric endoscopic approach to repair abdominal wall hernias. PATIENTS AND METHODS: We performed acute experiments under general anesthesia with endotracheal intubation using 50-kg pigs. Following peroral intubation an incision of the gastric wall was made and the endoscope was advanced into the peritoneal cavity. An internal anterior abdominal wall incision was performed with a needle knife to create an animal model of a ventral hernia. After hernia creation an endoscopic suturing device was used for primary repair of the hernia. After completion of the hernia repair the endoscope was withdrawn into the stomach and the gastric wall incision was closed with endoscopic clips. Then the animals were killed for necropsy. RESULTS: Two acute experiments were performed. Incision of the gastric wall was easily achieved with a needle knife and a pull-type sphincterotome. A large (3 x 2 cm) defect of the abdominal wall (ventral hernia model) was closed with five or six sutures using the endoscopic suturing device. Postmortem examination revealed complete closure of the hernia without any complications. CONCLUSIONS: Transgastric endoscopic primary repair of ventral hernias in a porcine model is feasible and may be technically simpler than laparoscopic surgery.

Transgastric endoscopic splenectomy: is it possible?

BACKGROUND: We have previously reported the feasibility of diagnostic and therapeutic peritoneoscopy including liver biopsy, gastrojejunostomy, and tubal ligation by an oral transgastric approach. We present results of per-oral transgastric splenectomy in a porcine model. The goal of this study was to determine the technical feasibility of per-oral transgastric splenectomy using a flexible endoscope. METHODS: We performed acute experiments on 50-kg pigs. All animals were fed liquids for 3 days prior to procedure. The procedures were performed under general anesthesia with endotracheal intubation. The flexible endoscope was passed per orally into the stomach and puncture of the gastric wall was performed with a needle knife. The puncture was extended to create a 1.5-cm incision using a pull-type sphincterotome, and a double-channel endoscope was advanced into the peritoneal cavity. The peritoneal cavity was insufflated with air through the endoscope. The spleen was visualized. The splenic vessels were ligated with endoscopic loops and clips, and then mesentery was dissected using electrocautery. RESULTS: Endoscopic splenectomy was performed on six pigs. There were no complications during gastric incision and entrance into the peritoneal cavity. Visualization of the spleen and other intraperitoneal organs was very good. Ligation of the splenic vessels and mobilization of the spleen were achieved using commercially available devices and endoscopic accessories. CONCLUSIONS: Transgastric endoscopic splenectomy in a porcine model appears technically feasible. Additional long-term survival experiments are planned.

Laparoscopic adjustable gastric banding for the treatment of morbidly obese patients: early outcome in a Chinese cohort.

OBJECTIVE: To evaluate the efficacy of laparoscopic adjustable gastric banding in the management of morbid obesity in a cohort of Chinese patients. DESIGN. Cohort study. SETTING: University teaching hospital, Hong Kong. PATIENTS: From August 2002 to September 2003, 10 patients (6 male, 4 female) with a median age of 34 years (range, 23-48 years) underwent laparoscopic adjustable gastric banding to treat morbid obesity. Considerable co-existing diseases were present in 90% of the cases. We instituted a team approach that allowed every patient to see our dietitian, physician, psychiatrist (if necessary), and surgeon prior to deciding on the procedure to be used. MAIN OUTCOME MEASURES: Excessive body weight loss, quality-of-life score (SF36), and co-morbidities improvement. RESULTS: The 10 patients had a median weight of 127 kg (range, 115-196 kg) and median body mass index of 47 kg/m(2) (range, 38-67 kg/m(2)). The operation was successful in all patients with a median operating time of 110 minutes (range, 75-240 minutes). The median hospital stay was 3 days (range, 3-4 days) and three of the patients required overnight observation in the intensive care unit because of severe sleep apnoea and asthma. The median follow-up period was 12 months (range, 1-18 months). The mean weight loss at 6, 12, and 18 months was 19.3, 22.4, and 25.9 kg, respectively. Mean percentage of excessive weight loss at 6, 12, and 18 months was 34.9%, 36.5%, and 40.5%, respectively. Unsatisfactory weight loss (<20 kg) occurred in three patients because of poor dietary compliance and non-follow-up. Surgery also considerably improved the patients' co-morbidities (hypertension, diabetes, and obstructive sleep apnoea) and the quality of life. CONCLUSION: In the short term, laparoscopic adjustable gastric banding is certainly an effective procedure for morbid obesity, which results in a substantial weight loss and improvement of co-existing morbidities. Longer follow-up will show whether this weight loss is maintainable.

Serum LD1 isoenzyme and blood lymphocyte subsets as prognostic indicators for severe acute respiratory syndrome.

BACKGROUND: The pathophysiology of severe acute respiratory syndrome (SARS) is at present poorly understood, but advanced age and serum total lactate dehydrogenase (LD) activity >300 U L(-1) have been associated with adverse clinical outcomes. Blood leucocytes and lymphocyte subsets were reported to decrease, respectively, in 47% and up to 100% of 38 patients in Beijing. However, their prognostic implications have not been thoroughly investigated. OBJECTIVE: To investigate serum total LD, LD isoenzymes, and other parameters including blood lymphocyte subsets as prognostic indicators in SARS patients for adverse clinical outcomes in terms of admission to intensive care unit (ICU) and death. DESIGN: Retrospective analysis. SUBJECTS AND METHODS: A total of 109 patients with a clinical diagnosis of SARS according to the modified World Health Organization case definition of SARS were recruited from two major acute hospitals in Hong Kong. They were either involved in the initial outbreak of SARS, or cases from the community outbreak of Amoy Gardens between 10 March and 5 May 2003. The clinical diagnosis was subsequently confirmed by serological test and/or molecular analysis. Serum total LD and LD isoenzyme activities, complete blood picture with total leucocyte count and differential counts, absolute counts of CD3+, CD4+, CD8+, natural killer cells and B lymphocytes were measured daily upon admission. Receiver operating characteristic curve analysis was used to determine and compare different cut-offs for various biochemical and immunological parameters at peak serum total LD concentration in predicting adverse clinical outcomes. RESULTS: Of a total of 109 patients, 41 were admitted to ICU and 42 died. Of 42 fatal patients, 24 died in ICU and 18 died in general medical wards. Age was found to be an independent prognostic indicator for death with an area under curve (AUC) of 0.96 [95% confidence interval (CI) = 0.90-0.99] but not for admission to ICU [AUC = 0.61 (CI = 0.51-0.70)]. Whilst serum total LD could only achieve AUC of 0.68 (CI = 0.59-0.77) for predicting death, LD1 isoenzyme was found to be the best biochemical prognostic indicator with AUC of 0.84 (CI = 0.75-0.90), sensitivity of 62% (CI = 46-76%), specificity of 93% (CI = 83-98%) at cut-off activity of > or =80 U L(-1). CD3+, CD4+, CD8+ and natural killer cell counts were promising immunological prognostic indicators for predicting admission to ICU with AUC of 0.94 (CI = 0.86-0.98), 0.91 (CI = 0.81-0.96), 0.93 (CI = 0.85-0.98), and 0.87 (CI = 0.76-0.94), respectively. CONCLUSIONS: Apart from age, serum LD1 activity was the best prognostic indicator for predicting death in patients with SARS compared with serum total LD activity, haemoglobin concentration, leucocyte and lymphocyte counts. Its release could possibly be from blood erythrocytes and body tissues other than the myocardium. Blood CD3+, CD4+, CD8+ and natural killer cell counts were found to be good prognostic indicators for predicting admission to ICU in patients with SARS compared with age, leucocyte count and LD isoenzymes. The suppressed CD3+, CD4+, CD8+, and natural killer cell counts were also implicated in the pathophysiology of SARS. Patients with increased serum LD1 should be closely monitored to ensure prompt management, and preparation for admission to ICU could be planned ahead for patients with suppressed lymphocyte subsets.

Comparison of breath-hold 2D phase-contrast with non breath-hold cine phase-contrast MRA in the assessment of azygos venous blood flow in portal hypertension.

Azygos venous blood flow as an index of blood flow through the gastroesophageal collaterals and varices is of value in the prediction of gastrointestinal bleeding. Measurement of azygos venous blood flow has been achieved by non breath-hold (NBH) cine phase-contrast magnetic resonance imaging. The objective of this study was to compare the faster breath-hold (BH) phase-contrast technique with the standard (NBH) cine phase-contrast technique in the measurement of azygos blood flow. Thirty-two cirrhotic patients with esophageal varices were examined by magnetic resonance imaging using a BH technique and a NBH cine phase-contrast technique to measure the flow velocity, flow volume and calibre of the azygos vein at the mid-right atrial level. The flow values were obtained on the velocity image of the phase-contrast study. Values obtained from the two methods were evaluated statistically for the strength and significance of correlation by the Pearson test. Measurement by the BH method performed at full-inspiration as well as end-expiration was also obtained in 15 healthy volunteers. The breath-hold phase-contrast method has significant but weak correlation with non BH cine phase-contrast method in the measurement of azygos venous blood flow volume (r = 0.55, p < 0.01) and flow velocity (r = 0.43, p = 0.01). However, the calibre of the azygos vein gave a strong correlation in these two methods (0.82). In the subgroup of patients whose azygos blood flow velocity was greater than 7.4 cm/s, the correlation of azygos blood flow volume is strong (r = 0.80, p < 0.01). The azygos vein calibre remains highly correlated between the BH and NBH method, in both high flow velocity (r = 0.73) and low flow velocity (r = 0.83) groups. Breath-hold sequence leads to higher values for flow velocity and flow volume in the cirrhotic patients and also the control group. In patients with portal hypertension, BH 2D phase-contrast (PC) magnetic resonance angiography (MRA) could give a comparable estimation of the calibre of the azygos vein as the NBH 2D cine PC MRA but not for azygos flow volume. In patients with high azygos flow velocity, the strong correlation in flow volume between the BH and NBH method suggests that the BH method may be a time-saving alternative to the NBH method.

Plasma inflammatory cytokines and chemokines in severe acute respiratory syndrome.

Severe acute respiratory syndrome (SARS) is a recently emerged infectious disease caused by a novel coronavirus, but its immunopathological mechanisms have not yet been fully elucidated. We investigated changes in plasma T helper (Th) cell cytokines, inflammatory cytokines and chemokines in 20 patients diagnosed with SARS. Cytokine profile of SARS patients showed marked elevation of Th1 cytokine interferon (IFN)-gamma, inflammatory cytokines interleukin (IL)-1, IL-6 and IL-12 for at least 2 weeks after disease onset, but there was no significant elevation of inflammatory cytokine tumour necrosis factor (TNF)-alpha, anti-inflammatory cytokine IL-10, Th1 cytokine IL-2 and Th2 cytokine IL-4. The chemokine profile demonstrated significant elevation of neutrophil chemokine IL-8, monocyte chemoattractant protein-1 (MCP-1), and Th1 chemokine IFN-gamma-inducible protein-10 (IP-10). Corticosteroid reduced significantly IL-8, MCP-1 and IP-10 concentrations from 5 to 8 days after treatment (all P < 0.001). Together, the elevation of Th1 cytokine IFN-gamma, inflammatory cytokines IL-1, IL-6 and IL-12 and chemokines IL-8, MCP-1 and IP-10 confirmed the activation of Th1 cell-mediated immunity and hyperinnate inflammatory response in SARS through the accumulation of monocytes/macrophages and neutrophils.

Imaging in severe acute respiratory syndrome (SARS).

Severe acute respiratory syndrome (SARS) is a highly infectious disease caused by a novel coronavirus, and has become pandemic within a short period of time. Imaging plays an important role in the diagnosis, management and follow-up of patients with SARS. The current status of imaging in SARS is presented in this review.

Early extubation after transthoracic oesophagectomy.

OBJECTIVES: To assess patient outcome following transthoracic (Ivor-Lewis) oesophagectomy and the effects of epidural analgesia and early extubation compared with overnight sedation and ventilation. DESIGN: Retrospective study. SETTING: University teaching hospital, Hong Kong. SUBJECTS AND METHODS: A retrospective review of patients undergoing oesophagectomy during two periods, 1990 to 1994 (n=65) and 1995 to 1998 (n=83), was completed. In the latter period, factors associated with early extubation were also evaluated. RESULTS: Between 1990 and 1994, only three (4.6%) of 65 patients were extubated early compared with 34 (41.0%) of 83 patients between 1995 and 1998 (P<0.001). Comparing these two periods, there were no differences in respiratory complications or hospital mortality. In the period 1995 to 1998, more patients who were extubated early had received epidural analgesia (85% versus 41%, P<0.001). There were no differences between the early and late extubation groups in terms of respiratory complications and hospital mortality. Patients extubated early had shorter stays in the intensive care unit (1 versus 2 days, P=0.005). Epidural analgesia was an independent factor associated with early extubation (odds ratio=9.4; 95% confidence interval, 2.8-31.2). CONCLUSION: After transthoracic oesophagectomy, early extubation is safe and can lead to a shorter stay in the intensive care unit. Epidural analgesia appears to facilitate early extubation.