PubMed Health⌕ Search

Biomedical subjects

J Ponsky

Publications and source records attributed to J Ponsky.

24 records · Page 2Linked to original sources
PubMed1993

The management of common bile duct stones in patients undergoing laparoscopic cholecystectomy.

The management of suspected and/or unsuspected common bile duct (CBD) stones in patients undergoing laparoscopic cholecystectomy (LC) is controversial. Decisions on whether to perform an open CBD exploration versus employing therapeutic options such as preoperative/post-operative endoscopic retrograde cholangiography (ERCP) or endoscopic duct exploration are polemic. To determine indications, timing, benefits, and potential morbidity of these approaches, we gathered data on 401 patients undergoing LC within the last 18 months. Indications for preoperative ERCP included jaundice (40%), dilated ducts (28%), elevated amylase (19%) or alkaline phosphatase (21%), suspicion of CBD stones by ultrasound (17%) and "other" (17%). Indications for postoperative ERCP were retained stones (33%) and CBD evaluation (67%). Indications for CBD exploration included abnormal cholangiogram (64%), palpable stones (18%), and other (18%). A significant correlation was observed between suspected stones by ultrasound and stones found by ERCP (P < 0.01). For patients in the "other" category, preoperative ERCP was universally negative (P = 0.04). Overall ERCP morbidity was 4/59 (6.8%), and the overall failure rate for clearing CBD stones was 2/28 (7.1%). The timing of the ERCP did not affect morbidity/mortality. Multivariate analysis revealed that age (P << 0.001), the presence of pre-existing medical risk factors (P << 0.001), and duration of LC (P = 0.0034), but not ERCP (P = 0.08), were the important factors determining LC morbidity. In summary, common bile duct stones can be successfully cleared endoscopically in the majority of patients undergoing LC. Patients with suspected CBD stones should undergo pre-operative ERCP, and strict criteria should be applied in the selection of these patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Endoscopic stent configuration and bile flow rates in a variable diameter bile duct model.

Endoscopically placed biliary stents are used in the treatment of biliary strictures and obstruction. Patency of the stent is related to bile flow rate through the stent. The purpose of this study was to examine the influence of stent diameter, configuration, and common duct diameter on bile flow rates. Flow rates were examined in straight and pigtail stents, 7 Fr and 10 Fr, and in a 1 cm and 2.3 cm diameter CBD model. Bile-flow rates were greater in the straight and 10 Fr stents. Bile-duct diameter had no influence on flow rate in pigtail stents. Though flow rates decreased with straight stents in bile ducts of increasing diameter, the absolute flow rates always remained greater in the straight stents when compared to the pigtail stents. We conclude that straight stents, because of greater flow rates, are to be preferred over pigtail stents for the treatment of biliary obstruction in dilated and nondilated systems.

Bile Ducts↗
PubMed1988

Endoscopic and histologic correlates of intestinal ischemia in a canine model.

The purpose of this study was to correlate endoscopic, microscopic and gross changes in an isolated ischemic segment of canine jejunum. Three experiments were devised. The arterial and venous blood supply to a 20 cm segment of distal jejunum in mongrel dogs was isolated and the bowel divided. External and endoscopic photography and intestinal biopsies were obtained at 0, 5, 15, 30, 60, 120, 180 and 360 minutes after vascular occlusion. Arterial occlusion was characterized by initial blanching of the mucosa, hyperperistalsis, edema, spasm and serosal pallor within 5 minutes. Microscopically, capillaries became congested at 5 minutes; epithelial sloughing occurred in 1-2 hours; necrosis of the tips of the villi occurred at 4 hours; and necrosis of muscle fibers was observed at 18 hours. Venous occlusion was characterized by marked mucosal and edema and hemorrhages within 5 minutes. At 15 minutes serosal hemorrhages were observed. Mucosal sloughing with hemorrhage and infarction were observed at 3 hours. Microscopically, mucosal capillary congestion was severe at 5 minutes and widespread hemorrhages were seen at 15 minutes. Mucosal sloughing began at 30 minutes and was severe by 60 minutes. Complete mucosal necrosis occurred by 3 hours. Combined arterial and venous occlusion was similar to arterial occlusion alone except for the early appearance of punctate mucosal hemorrhages. Massive submucosal hemorrhages did not occur. Results demonstrate that arterial and venous occlusion can be differentiated endoscopically; venous occlusion appears to be more readily injurious; and endoscopy and biopsy are valuable in diagnosis and management.

Animals↗
PubMed1988

Effects of transient ischemia on the healing small bowel anastomosis.

The small bowel may be subjected to transient, yet reversible ischemia in situations such as volvulus, thromboembolism, and low flow states. The surgeon is frequently faced with the necessity of intestinal resection in treating such cases. The remaining bowel, while judged viable may have been exposed to significant ischemic injury. The surgeon must decide whether such bowel will heal satisfactorily if used in an anastomosis. This study was undertaken to determine the effect of transient ischemia on intestinal anastomotic healing in the rat. Male albino rats were subjected to superior mesenteric artery occlusion for periods of 30 minutes or 45 minutes. The circulation was then re-established. The small bowel was the transected and anastomosed. Animals in each group were sacrificed at 7 and 10 days and bursting pressures performed to test the healing of the anastomosis. Results were compared with a control group having an anastomosis without precedent ischemia. There were no significant differences among the groups. The data clearly indicate that if the bowel remains viable following an ischemic insult its healing is unimpaired.

Animals↗
PubMedDate not supplied

Endoscopic tonometric assessment of intestinal perfusion in a canine model.

In an anesthetized canine model tonometric balloons were colonoscopically placed into the right colon, left colon, and rectum. A femoral arterial line was established for the measurement of blood pressure and arterial bicarbonate. Laparotomy was performed and additional balloons were placed, via enterotomies, into the duodenum, jejunum, and ileum. Baseline measurements of intramural pH were obtained, and then the origin of the superior mesenteric artery was occluded. Additional measurements in all areas were made for two 1-hour intervals. Results showed rapid and marked acidosis as demonstrated by significant (p less than 0.001) pH changes in the jejunum, ileum, and right colon. There were no significant changes in the pH in the duodenum, left colon, or rectum. Systemic arterial pH remained normal. These data demonstrate that tonometric balloons endoscopically placed into the right colon will reflect superior mesenteric artery occlusion at an early stage, and that similar information is likely to be gained by endoscopic placement of these balloons into the jejunum.

Animals↗