Importance of black carbon to sorption of native PAHs, PCBs, and PCDDs in Boston and New York harbor sediments.

The solid-water distribution ratios (Kd values) of "native" PAHs, PCBs, and PCDDs in Boston and New York Harbor sediments were determined using small passive polyethylene samplers incubated for extended times in sediment-water suspensions. Observed solid-water distribution coefficients exceeded the corresponding f(oc)Koc products by 1-2 orders of magnitude. It was hypothesized that black carbon (fBC), measured in the Boston harbor sediment at about 0.6% and in the New York harbor sediment at about 0.3%, was responsible for the additional sorption. The overall partitioning was then attributed to absorption into the organic carbon and to adsorption onto the black carbon via Kd = f(oc)Koc + f(BC)K(BC)C(w)n-1 with Cw in microg/L. Predictions based on published Koc, K(BC), and n values for phenanthrene and pyrene showed good agreement with observed Kd,obs values. Thus, assuming this dual sorption model applied to the other native PAHs, PCBs, and PCDDs, black carbon-normalized adsorption coefficients, K(BC)S, were deduced forthese contaminants. Log K(BC) values correlated with sorbate hydrophobicity for PAHs in Boston harbor (log K(BC) approximately 0.83 log gamma w(sat) - 1.6; R2 = 0.99, N= 8). The inferred sorption to the sedimentary BC phase dominated the solid-water partitioning of these compound classes, and its inclusion in these sediments is necessary to make accurate estimates of the mobility and bioavailability of PAHs, PCBs, and PCDDs.

Rectal cancer: the Basingstoke experience of total mesorectal excision, 1978-1997.

OBJECTIVE: To examine the role of total mesorectal excision in the management of rectal cancer. DESIGN: A prospective consecutive case series. SETTING: A district hospital and referral center in Basingstoke, England. PATIENTS: Five hundred nineteen surgical patients with adenocarcinoma of the rectum treated for cure or palliation. INTERVENTIONS: Anterior resections (n = 465) with low stapled anastomoses (407 total mesorectal excisions), abdominoperineal resections (n = 37), Hartmann resections (n = 10), local excisions (n = 4), and laparotomy only (n = 3). Preoperative radiotherapy was used in 49 patients (7 with abdominoperineal resections, 38 with anterior resections, 3 with Hartmann resections, and 1 with laparotomy). MAIN OUTCOME MEASURES: Local recurrence and cancer-specific survival. RESULTS: Cancer-specific survival of all surgically treated patients was 68% at 5 years and 66% at 10 years. The local recurrence rate was 6% (95% confidence interval, 2%-10%) at 5 years and 8% (95% confidence interval, 2%-14%) at 10 years. In 405 "curative" resections, the local recurrence rate was 3% (95% confidence interval, 0%-5%) at 5 years and 4% (95% confidence interval, 0%-8%) at 10 years. Disease-free survival in this group was 80% at 5 years and 78% at 10 years. An analysis of histopathological risk factors for recurrence indicates only the Dukes stage, extramural vascular invasion, and tumor differentiation as variables in these results. CONCLUSIONS: Rectal cancer can be cured by surgical therapy alone in 2 of 3 patients undergoing surgical excision in all stages and in 4 of 5 patients having curative resections. In future clinical trials of adjuvant chemotherapy and radiotherapy, strategies should incorporate total mesorectal excision as the surgical procedure of choice.

Recent trends in diagnosis and treatment of Clostridium difficile in a tertiary care facility.

BACKGROUND: With the prevalence of antibiotic use, the diagnosis and management of Clostridium difficile disease requires assessment. METHODS: In a retrospective review, patients with a positive culture, toxin, or both during 1 year were identified. Recent literature was reviewed. Results of culture and toxin, prior antibiotic use, antibiotic treatment history and cost were analyzed. RESULTS: Of 592 patients tested, 101 were positive; 96 of 101 were available for review. Of those positive tested for both, 45% were positive for toxin and culture. Sixty-two of 96 were treated with antibiotics; metronidazole was used in 90%. Ten of 62 antibiotic treatments were changed (mean 3 days). Ten days of metronidazole is 1/200th the cost of vancomycin. CONCLUSIONS: In 55% of the positive cases in which culture and toxin were obtained, one test was negative. As metronidazole's efficacy and cost compares favorably with vancomycin, metronidazole is the drug of choice. Any changes made to antibiotic regimens occurred prior to the 6 days recommended in the literature.

An alternative approach to acute cholecystitis. Percutaneous cholecystostomy and interval laparoscopic cholecystectomy.

BACKGROUND: The mainstay of therapy for acute cholecystitis is cholecystectomy, which has a mortality of 5-30% in high-risk patients such as the elderly or critically ill. An alternative treatment option in patients suffering from acute cholecystitis with contraindications to emergency surgery is percutaneous cholecystostomy (PC) followed by interval laparoscopic cholecystectomy. Percutaneous cholecystostomy yields 10-12% mortality in high-risk patients and is therefore a safe temporizing measure, allowing delayed, elective cholecystectomy when the patient is in better condition for surgery. METHODS: Hospital charts and radiology films were reviewed for all 50 patients who underwent PC for acute cholecystitis between January 1990 and September 1993. Most patients were high risk for emergency cholecystectomy by virtue of their critical illness or underlying medical condition. Twenty-five patients went on to have interval cholecystectomies. We recorded whether they underwent laparoscopic or open cholecystectomy, as elective or emergency procedures, and we recorded direct complications, mortality, and postoperative length of hospital stay. RESULTS: Relief of symptoms occurred within 48 h of PC in 90% of patients, and two patients had complications of PC. Laparoscopic cholecystectomy was attempted in 13 patients and competed in nine. Four patients (31%) required conversion from laparoscopic to open cholecystectomies due to extensive adhesions (3) or bleeding (1). Three patients had direct complications of laparoscopic cholecystectomy. There was no mortality or major bile duct injury. CONCLUSION: Percutaneous cholecystostomy followed by interval laparoscopic cholecystectomy is a safe, minimally invasive approach which can be employed safely in the critically ill patient when contraindications to emergency surgery exist.

Peritoneal abscesses due to bowel perforation: effect of extent on outcome after percutaneous drainage.

PURPOSE: To determine the effect of extent of peritoneal contamination in enteric abscesses on final outcome and duration of percutaneous drainage. PATIENTS AND METHODS: Results were retrospectively reviewed for 11 patients with varying degrees of peritoneal contamination secondary to subacute bowel perforation who were primarily treated with percutaneous drainage. Stepwise linear regression analysis of duration of drainage was performed with use of patient age and immune status, the site of bowel perforation, and the number of peritoneal compartments involved in the resultant contamination as independent variables. RESULTS: In 10 of 11 patients (91%) treatment of the resultant intraperitoneal collections with percutaneous drainage was successful irrespective of the extent of peritoneal contamination. There was no correlation between duration of drainage and extent of peritoneal contamination but good correlation with patient age and site of bowel perforation (r = 0.82, P = .02). CONCLUSION: In patients with enteric abscesses due to subacute bowel perforation, the duration of drainage and final outcome after percutaneous drainage are independent of the extent of peritoneal contamination.

Radiologically guided percutaneous cholecystostomy for acute cholecystitis: long-term outcome in 50 patients.

To assess the long-term outcome in patients with acute cholecystitis treated initially by percutaneous cholecystostomy, the authors reviewed the medical and radiology records of all such patients treated at their hospital from January 1990 to September 1993. Of the 50 patients, 29 had calculous and 21 had acalculous cholecystitis. In the group with calculous cholecystitis, 1 of the patients required no further treatment, 3 subsequently underwent percutaneous stone removal, 14 underwent elective cholecystectomy, 6 underwent emergency cholecystectomy and 5 died of the underlying condition shortly after cholecystostomy. In the group with acalculous cholecystitis, 12 of the patients needed no further treatment after a mean follow-up period of 12 months; 8 of these underwent follow-up ultrasound examination, which revealed gallbladder calculi in only 1 patient. Four patients underwent elective cholecystectomy, 1 underwent emergency cholecystectomy, and 4 died of the underlying condition shortly after cholecystostomy. Over the long term, 23 (79%) of the 29 patients with calculous cholecystitis underwent surgery or removal of calculi. In the other group surgery was required in only 5 (24%) of the 21 patients. The authors conclude that percutaneous cholecystostomy is a useful temporizing measure, which allows patients with calculous cholecystitis to undergo elective cholecystectomy. In most cases of acalculous cholecystitis the procedure is curative, obviating the need for cholecystectomy.

Malignant obstruction of the common bile duct: long-term results of Gianturco-Rosch metal stents used as initial treatment.

PURPOSE: To determine how long Gianturco-Rosch metal stents remain patent when used as the initial treatment for malignant obstruction of the common bile duct. MATERIALS AND METHODS: The patency of Gianturco-Rosch metal stents was prospectively studied in 26 patients with malignant obstructive jaundice. Biliary obstruction was caused by pancreatic carcinoma (n = 15), cholangiocarcinoma (n = 10), or metastatic lymphadenopathy (n = 1). Follow-up information was obtained every 3-4 months until death. RESULTS: Stent insertion was successful in all patients. Stent occlusion occurred in nine patients (35%). The overall mean patency period was 39.9 weeks. Adequate biliary drainage for a minimum of 80 weeks or until death was achieved in 19 patients (73%). Life-table analysis predicted stent patency rates of 86%, 75%, and 69% at 12, 24, and 48 weeks, respectively. CONCLUSION: These results are better than those previously reported in patients with plastic endoprostheses. The authors believe that insertion of the metal stent is the procedure of choice in patients with inoperable malignant biliary obstruction.

Percutaneous cholecystostomy: safety of the transperitoneal route.

PURPOSE: The authors analyzed the safety and efficacy of transperitoneal percutaneous cholecystostomy (PC) in patients with acute cholecystitis. PATIENTS AND METHODS: Thirty-four consecutive patients underwent transperitoneal PC for treatment of acute cholecystitis. A trocar technique was used for placement of the drainage catheter. RESULTS: PC was technically successful in all patients. In 27 (79%) of 34 patients, symptoms of acute cholecystitis resolved within 7 days. Minor complications occurred in two patients (5%). Both patients developed a hematoma adjacent to the gallbladder; these resolved without treatment. No cases of bile leak or bile peritonitis occurred. CONCLUSION: The transperitoneal route is safe and effective for PC.