Development of a total colonoscopy rat model with endoscopic submucosal injection of the cecal wall.

BACKGROUND: Experimental models of colorectal tumor require either laparotomy for induction or anastomosis following resection. The long murine cecum avoids the need for an anastomosis, making the cecum the preferred site for induction. This study aimed to evaluate total colonoscopy with submucosal injection of cecal wall (TCWI) in rats in terms of failure rate (FR), complication rate (CR), and reproducibility (R). METHODS: A bolus of bowel prep was given. Anesthesia was injected intraperitoneally. A video fiberscope (5.9 mm outer diameter, 180/90 degrees up/down bending, 100/100 degrees right/left bending, 103 cm working length, 120 degrees view field, and 2.0 mm channel) allowed for irrigation and suction. Saline 1 ml was injected in the cecal wall through a 4-mm-long, 23-gauge needle placed on a 3-mm wire, resulting in a blister. FR was a failure to reach and inject the cecum. Rats were allowed to recover. CR was measured at necropsy. R was assessed by comparing TCWI time, FR, and CR for three investigators. Sample size of 120 (type I error, 0.05; power, 80%) was based on a pilot study. Data are presented as median (range). RESULTS: A total of two of 122 rats (1.6%) died after prep or anesthesia. Bowel prep resulted in 99.1% evacuation of solid feces. A total of 120 male Sprague-Dawley retired breeders weighing 592 g (range, 349-780) underwent TCWI. Scope depth was 28 cm (range, 20-36). Irrigating fluid was 290 ml (range, 100-600). TCWI time was 7 min (range, 4-28). FR was 4%. In three failed cases, the scope reached the ascending colon. CR was 2%. There were two perforations in the ascending colon. All three operators had similar TCWI time (p = 0.673), FR (p > 0.1), and CR (p > 0.1). A total of 98.3% of rats survived to planned sacrifice. At 48-h necropsy, the injection site was macroscopically identified in 118 rats. CONCLUSIONS: A safe and reproducible TCWI rat model has been achieved, which may provide a valuable tool in the future for studies of solid colorectal tumors.

In vitro evaluation of the susceptibility of Edwardsiella ictaluri, etiological agent of enteric septicemia in channel catfish, Ictalurus punctatus (Rafinesque), to florfenicol.

In vitro studies were conducted to assess the sensitivity of Edwardsiella ictaluri, the etiological agent of enteric septicemia of catfish (ESC), to the antibacterial drug florfenicol (FFC). Twelve different E. ictaluri isolates from cases submitted between 1994 and 1997 to the Thad Cochran National Warmwater Aquaculture Center fish diagnostic laboratory (Stoneville, MS) were used for testing. These isolates originated from channel catfish (Ictalurus punctatus) infected with E. ictaluri through natural outbreaks of ESC in the commercial catfish ponds in Mississippi. Seven hundred sixty-seven additional cultures of E. ictaluri were obtained from channel catfish infected experimentally with E. ictaluri. In some of these experimental infections, FFC was used for treatment. These cultures of E. ictaluri were identified by morphological and biochemical tests. Kirby-Bauer zones of inhibition (in mm) for FFC against E. ictaluri were determined using standard methods. The minimum inhibitory concentration (MIC) of FFC was determined for the natural outbreak E. ictaluri isolates and arbitrarily selected experimental cultures. The zones of inhibition for FFC tested with E. ictaluri ranged from 31 to 51 mm. The MIC for FFC tested with E. ictaluri was consistently 0.25 microg/ml. Edwardsiella ictaluri tested in these studies were highly sensitive to FFC in vitro.

The presence of colorectal hepatic metastases does not preclude pulmonary metastasectomy.

Hepatic metastases due to colorectal carcinoma have often been felt to preclude pulmonary metastasectomy. With the recent advances in surgical options, should patients with both liver and lung metastases be considered for surgical resection? The current study reviews the impact of such aggressive management on disease-free and overall survival (OS). The clinical course of 63 patients presenting with colorectal metastasis to the lung alone (group 1, n = 45) or combined hepatic and lung metastases (group 2, n = 18) were reviewed. All patients underwent complete resection of their lung metastases. Surgical control of hepatic tumor burden was achieved by tumor ablation, intra-arterial therapy, and/or resection. All patients in group 1 and group 2 were available for a mean follow-up of 27 and 24 months, respectively. The presence of hepatic metastases, the resectability of hepatic tumor burden, and the disease-free interval after pulmonary metastasectomy did not significantly influence survival. These findings demonstrate that aggressive surgical management of pulmonary metastases in the presence of liver metastases offers a similar benefit as compared to patients with pulmonary metastases alone. Therefore, hepatic metastatic disease does not preclude an attempt at pulmonary metastasectomy if hepatic metastases can be resected or remains responsive to therapy. Such an approach achieves comparable OS and mean survival when compared to pulmonary metastasectomy alone.

Bilateral anterior minithoracotomy with video assistance for lung volume reduction surgery and pulmonary metastasectomy.

Incisional access to pulmonary pathology involving both lungs has often involved bilateral standard thoracotomies, median sternotomy, and, recently, sequential lateral video-assisted thoracic surgical approaches. Significant problems are inherent to each of these approaches. We introduce a hybrid technique of bilateral simultaneous minithoracotomy with video assistance as an alternative to these other surgical approaches.

Immediate radiographic assessment following laparoscopic antireflux operations is unnecessary.

BACKGROUND: Laparoscopic antireflux operations (LAP) have become increasingly common for the treatment of gastroesophageal reflux disease (GERD). We sought to determine if routine postoperative barium contrast studies following LAP were clinically efficacious in identifying technical problems and life-threatening complications related to the surgical intervention. METHODS: From January 1996 to December 1997, 112 barium studies were performed following 112 LAP procedures (47 male/65 female patients; mean age, 51 years) (group I). This group was compared to a subsequent cohort of 67 patients who underwent LAP between January 1998 and July 1998 without routine early postoperative barium contrast study (group II). RESULTS: In 111/112 of the barium studies of group I, no radiographic abnormality was identified. The average length of stay (LOS) for these patients was 2.6 days. Routine barium studies were not utilized in group II. The average length of stay for patients in group II was 1.4 days. Twelve group II patients underwent early postoperative barium studies to evaluate suspicious clinical symptoms. None of these 12 postoperative studies identified important problems, nor did they alter the patients' clinical management. However, because of the barium study, their LOS was equivalent to those patients who had undergone routine barium study (2.4 days). There was an increase of $1451.80 in hospital charges in the group of patients who had a barium study, largely as a result of the increased LOS. CONCLUSION: The routine use of these studies results in increased patient charges and a prolongation in the length of hospital stay. Immediate postoperative barium studies following laparoscopic antireflux operations are of little value in determining important postoperative problems among patients undergoing LAO.

Laparoscopic management of giant paraesophageal herniation.

BACKGROUND: Many surgeons have found laparoscopic fundoplication effective management of medically recalcitrant gastroesophageal reflux disease (GERD) associated with sliding type I hiatal hernias. The anatomic distortion and technical difficulty inherent with repair has limited the use of laparoscopy for repair of "giant" paraesophageal hernias (gPH). METHODS: Since July 1993, we have accomplished laparoscopic repair of paraesophageal hiatal hernias in 54 of 60 (90%) patients. Five patients had classic type II hernias with total intrathoracic stomachs, and 53 patients had large sliding/paraesophageal type III herniation. Two patients had true parahiatal hernias. None had gastric incarceration. Median age was 53 years and 28 of 60 (47%) were women. Chest pain and dysphagia were primary complaints from 39 of 60 (65%). Heartburn with or without regurgitation was present in 52 of 60 (85%). Preoperative manometry and prolonged pH testing were obtained on 43 of 60 (72%) and 44 of 60 (73%) patients, respectively. Principles of repair included reduction of the hernia, excision of the sac, crural approximation, and fundoplication over a 54F bougie (Nissen, 41; Dor, 1; Toupet, 18) to "pexy" the stomach within the abdomen and to control postoperative reflux. RESULTS: Mean operative time was 202+/-81 minutes. Conversion to "open" repair was required in 6 patients (iatrogenic esophageal injury in 2 patients and difficult hernia sac dissection in 4 patients). One postoperative mortality occurred as a result of sepsis and multiorgan failure after an intraoperative esophageal perforation. Follow-up barium swallow performed in 44 of 60 patients demonstrated recurrent hiatal hernias in 3 patients. Preoperative symptoms have been relieved in all but 3 patients. Reoperation for recurrent paraesophageal herniation has been required in these latter 3 patients. CONCLUSIONS: Although technically challenging, laparoscopic repair of paraesophageal hiatal hernias is a viable alternative to "open" surgical approaches. Control of the herniation and the patient's symptoms are equivalent and hospitalization and return to full activity are shorter.

Experience and technique of stapled mechanical cervical esophagogastric anastomosis.

BACKGROUND: Anastomotic leak from cervical esophagogastric anastomoses is a serious problem after esophagectomy. We explored the efficacy of partial or total mechanical anastomoses accomplished with the endoscopic linear cutting and stapling device as an alternative to hand-sewn anastomotic techniques. METHODS: During a 42-month period, 93 patients undergoing either transhiatal esophagectomy or a three-incisional approach to esophagectomy underwent either hand-sewn (n = 43), partial mechanical (n = 16), or totally mechanical (n = 34) cervical esophagogastric anastomoses. The occurrence of postoperative anastomotic leak and the development of postoperative anastomotic stricturing requiring dilation therapy were analyzed between these groups using chi2. RESULTS: All patients survived esophagectomy and were available for postoperative follow-up. Anastomotic leak developed in 10 patients (23%) with hand-sewn, 1 patient (6%) with partial mechanical, and 1 patient (3%) with total mechanical anastomoses (p < 0.05). Anastomotic stricture development paralleled the occurrence of anastomotic leak rate with 25 patients (58%) with hand-sewn, 3 patients (19%) with partial mechanical, and 6 patients (18%) with total mechanical anastomoses experiencing strictures requiring dilation therapy (p < 0.05). CONCLUSIONS: These results suggest that partial or mechanical cervical esophagogastric anastomoses created with the endoscopic stapling device may be superior to hand-sewn anastomotic techniques.

A comparative study of buttressed versus nonbuttressed staple line in pulmonary resections.

BACKGROUND: Prolonged air leak is the major limiting factor in early hospital discharge following pulmonary resection. The purpose of this study was to determine whether the use of bovine pericardial strips as a buttress along the lung staple line would decrease air leaks and hospital stay after lobectomy and segmentectomy. METHODS: This was a multicenter trial consisting of 80 patients undergoing pulmonary resection, randomly assigned to the control group (40 patients) or treatment group (40 patients). The treatment group had reinforcement with bovine pericardium. RESULTS: No statistical differences were noted in the mean intensive care unit length of stay (p = 0.9), number of days with a chest tube (p = 0.6), or total length of stay (p = 0.24). Increased air leak duration was associated with assignment to the control group (r = 0.27, p = 0.02). The mean duration of air leak was 2 days and the mean time to chest tube removal was 5.9 days in patients with a buttressed staple line compared to 3 days and 6.3 days, respectively, for patients with nonbuttressed staple lines. CONCLUSIONS: Within the data of this study, no statistical differences were noted between buttressed and nonbuttressed patients. However, the trend toward shortened air leak time and tube removal time was apparent in the buttressed group. With greater number of patients studied, it is likely that the cost of bovine pericardium would be justified by shorter air leak duration and hospitalization.

Vascular endothelial growth factor expression in stage I non-small cell lung cancer correlates with neoangiogenesis and a poor prognosis.

BACKGROUND: Vascular endothelial growth factor (VEGF) plays an important role in tumor growth and metastasis. We investigated the prognostic significance of VEGF overexpression, intratumoral microvessel density (MVD), and angiolymphatic invasion in stage Ia-b non-small cell lung cancer (NSCLC). METHODS: Eighty-five patients undergoing complete surgical resection of pathologic stage Ia-b NSCLC were evaluated. The mean and median clinical follow-up were 37.1 and 39.0 months (range, 30-44 months), respectively. Paraffin-embedded tumor specimens were stained with VEGF and CD31 (a specific endothelial marker) using immunohistochemical methods. VEGF staining was evaluated, by combining both percentage of positive tumor cells and staining intensity, as low (negative and < 20% of tumor cells showing weak positivity), or high (> 20% of tumor cells showing strong positivity). CD31 staining was expressed as MVD per high power field at 400x magnification. Angiolymphatic invasion was expressed as either presence or absence. RESULTS: Low VEGF expression was seen in 25 (29%) patients, and high VEGF expression was seen in 60 (71%) patients. The survival rate in patients with low VEGF expression was significantly higher (80%) than that in those with high VEGF expression (48%, P = .018). The mean MVD in the low VEGF group was 23.7 +/- 5.7 vs. 34.4 +/- 9.3 in the high VEGF group (P = .001). Patients with high MVD also had a significantly lower survival rate than did those with low MVD count (46% vs. 73%, P = .0053). Age, sex, tumor type, and tumor differentiation were not found to be associated with overall survival. The presence of angiolymphatic invasion and T2 stage (i.e., tumor size > 3 cm) were associated with decreased survival. High VEGF expression, tumor size, and angiolymphatic invasion emerged as three independent factors predicting worsening prognosis using multivariate analysis. CONCLUSION: High VEGF expression within stage I NSCLC is closely associated with high intratumoral angiogenesis and poor prognosis. Immunohistochemical evaluation of T stage and VEGF expression along with examination of angiolymphatic invasion perioperatively may aid in predicting prognosis. Adjuvant therapies aimed at retarding tumor angiogenesis may be considered for stage I NSCLC patients with high VEGF levels.

Reoperative laparoscopic antireflux surgery.

BACKGROUND: Laparoscopic antireflux surgery (LAP) is becoming increasingly used for the surgical treatment of medical recalcitrant gastroesophageal reflux disease (GERD). We sought to determine the utility of remedial LAP approaches to antireflux surgery. METHODS: From March 1996 to December 1998, 15 patients underwent remedial LAP to manage medically recalcitrant recurrent GERD after LAP (n = 8) or open antireflux procedure (n = 1) and/or troublesome postfundoplication complications (dysphagia 6, gas bloat 4). The remedial LAP surgery consisted of conversion from Nissen to Toupet fundoplication to manage dysphagia or gas bloat symptoms (n = 7), revision of IAP Nissen fundoplication (n = 7) and LAP revision of a failed open Nissen fundoplication (n = 1) for recurrent reflux. RESULTS: The remedial LAP repair was accomplished in all patients. Findings at operation included disrupted fundoplication (n = 6), incomplete or inappropriately positioned fundoplication (n = 2), paraesophageal hernia (n = 3), or a normal total fundoplication among patients with primary dysphagia (n = 4). Follow-up symptom scoring beyond 3 months of remedial surgery demonstrated a change from the preoperative mean dysphagia, heartburn, gas bloat, and regurgitation score (P < .05). Follow-up GERD testing (manometry, upper gastrointestinal tract, pH testing) was normal in 13 of the 15 patients. CONCLUSIONS: Reoperative antireflux surgery can be accomplished using LAP approaches without compromise of therapeutic intent or increased surgical morbidity. Surgeons sufficiently experienced with these LAP repairs may consider repeat LAP instead of open surgery for patients with recurrent GERD or postfundoplication problems.

Video-assisted surgical management of achalasia of the esophagus.

PURPOSE: Video-assisted surgical approaches to esophageal achalasia continue to be explored by many surgeons involved in the management of this motor disorder. We report our experience with thoracoscopic and laparoscopic esophagomyotomy to more clearly define the efficacy and safety of these approaches. PATIENTS: Over 73 months, 58 patients with achalasia underwent thoracoscopic myotomy (n = 19) alone or laparoscopic myotomy (n = 39) with partial fundoplication (anterior = 15; posterior = 24). Mean age was 47.2 years and average length of symptoms was 60 months. Primary symptoms were as follows: dysphagia, 100%; pulmonary abnormalities, 22%; weight loss; 47%, and pain, 45%. Mean esophageal diameter was 6 cm and tortuosity was present in 16% (9/58) of patients. Prior management consisted of dilation (n = 47), botulinum toxin injection (n = 8), and prior myotomy (n = 1). METHODS: In the operating room all patients underwent endoscopic examination and evacuation of retained esophageal contents. The esophagomyotomy was extended 4 cm superiorly and inferiorly to 1 cm beyond the lower esophageal sphincter. Thoracoscopic and laparoscopic procedures were completed in all patients without conversion to an open operation. Mean operative time was 183 minutes (+/-58.1) and hospital stay averaged 2.3 days (+/-0.8). There was no operative mortality. The 1 operative complication was a perforation that was identified during the operation and repaired thoracoscopically. RESULTS: Symptoms improved in 97% of patients. Mean dysphagia scores (range 0-10) decreased from 9.8 +/- 1.6 before the operation to 2.0 +/- 1.5 after the operation (P <.001) at a mean follow-up of 6 months. Postoperative reflux symptoms developed in 5% (1/19) of the thoracoscopy group and 8% (4/39) of the laparoscopy group. Nine patients have persistent or recurrent dysphagia (16%). Seven patients have successfully undergone Savary dilation, and 2 required esophagectomy to manage recalcitrant dysphagia. CONCLUSION: At this intermediate term analysis, video-assisted approaches for management of achalasia are a reasonable alternative to extended medical therapy or open operations.

Intraoperative 125I brachytherapy for high-risk stage I non-small cell lung carcinoma.

PURPOSE: Preliminary assessment of feasibility, efficacy, acute and chronic side effects associated with permanent intraoperative placement of 125I vicryl mesh brachytherapy in a select group of high-risk Stage I NSCLC who have undergone video-assisted thoracoscopic resection (VATR). METHODS AND MATERIALS: From January 8, 1997 to March 16, 1998, 23 patients with Stage I NSCLC at high risk for conventional surgery due to cardiopulmonary compromise underwent combined VATR and intraoperative placement of 125I seeds embedded in vicryl mesh. Seeds embedded in vicryl suture were attached with surgical clips to a sheet of vicryl mesh, and thoracoscopically inserted over the target area (tumor bed and staple line) with nonabsorbable suture or surgical clips. A total dose of 100-120 Gy prescribed to the periphery of the target area (defined as the staple line and tumor bed with a 1-cm margin) was delivered. RESULTS: The mean target area covered was 48 cm2 (range 40-72) and mean total activity was 22 mCi (range 17.2-28.2). The median length of postoperative stay was 7 days. The median follow-up was 11 months (range 2-20). Postoperative CT scans of the chest revealed no dislodgement of the seeds and no local recurrence in any patient. Three patients developed distant metastasis (1 died 6 months postoperatively; the other 2 are currently alive with disease). One patient developed an ipsilateral recurrence in the right lower lobe after having had a right upper lobe resection. There were 3 postoperative deaths due to medical comorbid conditions or surgical complications (1 in the immediate postoperative period). Pulmonary function testing performed 3 months after implantation revealed no significant difference between preoperative and postoperative values: mean preoperative FVC was 2.3 L (range 1.31-3.0) and postoperative FVC was 2.2 L (range 1.1-3.9), p = 0.42; mean preoperative FEV1 was 1.2 L (range 0.71-2.2), and postoperative FEV1 was 1.5 L (range 0.8-2.9), p = 0.28. CONCLUSION: Review of early data suggests that intraoperative 125I vicryl mesh brachytherapy in high-risk Stage I NSCLC is potentially effective and well tolerated, with no significant decline in measurable pulmonary function studies and no increase in postoperative complications. Longer follow-up is needed to determine ultimate local control and survival.

Success of laparoscopic fundoplication for gastroesophageal reflux disease.

BACKGROUND: We explored the efficacy of laparoscopic fundoplication (LF) in patients with uncomplicated, medically recalcitrant pathologic gastroesophageal reflux disease (GERD) for whom we previously would have recommended open surgical repair. METHODS: From January 1994 to January 1998, we performed LF on 150 patients (80 men and 70 women) with GERD recalcitrant to maximal medical therapy. No patient suffered from esophageal stricture or epithelial dysplasia; however 16% (24 of 150) had benign Barrett's mucosa. Preoperative esophageal manometry and 24-hour pH testing were obtained in 93% (139 of 150) and 89% (134 of 150) of patients, respectively. Nissen LF (n = 123), Toupet LF (n = 26), or Dor LF (n = 1) were accomplished over a large (54 F) intraesophageal bougie. Preoperative (1 month) and postoperative (>6 month) symptom scoring were assessed on a 0 to 10 scale. Thirty-eight patients with a greater than 6-month postoperative period had manometry and pH studies performed. RESULTS: The laparoscopic approach was successful in 99% (148 of 150) of patients, and there has been no mortality. Operative time was 160+/-59 minutes. Open conversion was required for 2 patients: because of difficulty with dissection owing to adhesions in 1 case and due to perforation in another. Reoperation was required for 5 patients (1 paraesophageal, 2 dysphagia, 2 recurrent reflux). Major postoperative complications involved stroke and pancreatitis in 1 patient each. Mean hospital stay was 2.6+/-1.2 days, full activity resumed by 7 days. Postoperative esophageal pH testing among 38 patients tested more than 6 months after operation demonstrated normal esophageal acid exposure in all but 2. GERD symptoms were relieved at 1 month, 6 months, and after 1 year in 95% (128 of 135), 94% (99 of 105), and 93% (65 of 70) of patients, respectively. CONCLUSIONS: Intermediate-term results with LF suggest this to be a reasonable approach to surgical management of medically recalcitrant uncomplicated GERD. Thoracic surgeons interested in GERD should become familiar with minimally invasive surgical approaches.

Hemitruncus presenting in an adult. A case report.

Hemitruncus is a rare congenital anomaly in which one pulmonary artery branch, usually the right, arises from the ascending aorta just above the aortic sinuses, whereas the main pulmonary artery and the other pulmonary branch arise in their normal position. The authors present a case in which the patient was diagnosed as having hemitruncus as an adult, and to the best of their knowledge only 7 similar cases have been reported in the medical literature.

Fish mortality in the Mississippi catfish farming industry in 1988: causes and treatments.

The 1988 fish mortality summary for the catfish (Ictalurus punctatus) industry in Mississippi is presented. In 1988, 2,456 cases were submitted to Mississippi Cooperative Extension Service fish disease laboratories at Belzoni and Stoneville. Bacterial infection caused by Edwardsiella ictaluri was the leading cause of catfish mortality. Descriptions and treatments are presented for bacterial, parasitic, viral and other diseases affecting Mississippi farm-raised catfish in 1988.

Naturally occurring antibodies in human sera that react with Haemophilus influenzae type b ribosomal vaccine.

Sera from populations of normal adults and children as well as sera from children with systemic Haemophilus influenzae type b disease were tested for antibodies reacting with ribosomes from H. influenzae type b. Adults generally had high titers of antibody, with 90% having titers greater than 1:64. The distribution of titers approximated a normal curve. Among normal children, there was more variability between individual titers, with the median titers ranging between 1:64 and 1:128. In contrast, acute-phase sera from children with systemic H. influenzae type b disease all had titers of 1:16 or less. Two convalescent-phase sera had high titers. Absorption experiments ruled out cross-reaction between ribosomes and type b capsular material. Ribosomes from two unrelated type b strains were completely cross-reactive, whereas absorption with ribosomes from a type c strain led to significantly decreased titers in three of four sera. Absorption of sera with ribosomes from Pseudomonas aeruginosa and Streptococcus pneumoniae also decreased titers, indicating that these antibodies may have been induced by ribosomes of other bacteria.