Substrate utilization in leg muscle of men after heat acclimation.

Eight men were heat acclimated (39.6 degrees C and 29.2% rh) for 8 days to examine changes in substrate utilization. A heat exercise test (HET), (cycling for 60 min; 50% maximal O2 consumption) was performed before (UN-HET) and after (ACC-HET) the acclimation period. Muscle glycogen utilization (67.0 vs. 37.6 mmol/kg wet wt), respiratory exchange ratio (0.85 +/- 0.002 vs. 0.83 +/- 0.001), and calculated rate of carbohydrate oxidation (75.15 +/- 1.38 vs. 64.80 +/- 1.52 g/h) were significantly reduced (P less than 0.05) during the ACC-HET. Significantly lower (P less than 0.05) femoral venous glucose (15, 30, and 45 min) and lactate (15 min) levels were observed during the ACC-HET. No differences were observed in plasma free fatty acid (FFA) and glycerol concentrations or glucose, lactate and glycerol arteriovenous uptake/release between tests. A small but significant increase (P less than 0.05) above resting levels in FFA uptake was observed during the ACC-HET. Leg blood flow was slightly greater (P greater than 0.05) during the ACC-HET (4.64 +/- 0.13 vs. 4.80 +/- 0.13 l/min). These findings indicate a reduced use of muscle glycogen following heat acclimation. However, the decrease is not completely explained by a shift toward greater lipid oxidation or increased blood flow.

Surgical implications of fibrinolytic therapy.

Intraarterial fibrinolytic therapy was used in 37 cases (34 patients) of severe peripheral ischemia. Nineteen patients (56 percent) required surgical intervention (5 amputations and 14 successful reconstructive procedures). Twenty-four patients (71 percent) were significantly improved (average ankle-to-arm index 0.84), whereas only 5 patients (15 percent) lost their limbs. Five patients were angiographically unchanged with no or slight improvement in the ankle-to-arm index (0.22 to 0.32) and were discharged on anticoagulant therapy. One death and two cerebrovascular accidents occurred. The usefulness of intraarterial fibrinolytic therapy needs to be evaluated within the total realm of vascular surgery. It offers options for therapy where previously none existed. Some situations might be treated equally well with either intraarterial fibrinolytic therapy or surgery. Finally, surgery might be required to maintain initial successful results with intraarterial fibrinolytic therapy or to rescue intraarterial fibrinolytic therapy failures in striving to achieve superior results in limb salvage.

Cholecystectomy concomitant with other intra-abdominal operations. Assessment of risk.

In a retrospective study, 1,416 cholecystectomies performed during a three-year period were reviewed to define the risk of cholecystectomy when combined with another intra-abdominal procedure. Group 1, cholecystectomy alone (1,148 patients), with subsets of cholangiography and/or common bile duct exploration, had a complication rate of 14.29% and a mortality of 0.52%. Group 2, primary cholecystectomy combined with secondary intra-abdominal surgery (214 patients), had a complication rate of 19.63%. Group 3, primary intra-abdominal surgical procedure with incidental cholecystectomy (54 patients), had a complication rate of 20.37%. Mortality for groups 2 and 3 was 2.24%. The rate of nonfatal complications was increased slightly when a second surgical procedure was performed (14.29% v 19.78%). Pairing cholecystectomy with other intra-abdominal surgery is advised only when surgical exposure is adequate, the patient's condition is satisfactory, and operating time is not prolonged greatly.

Axillofemoral bypass: a ten-year review.

During a ten-year period (1969-1980), 106 grafts were implanted in the axillofemoral and axillobifemoral positions. This retrospective study is based on life table analysis of cumulative patency rates in both axillofemoral and axillobifemoral grafts, with and without thrombectomy. Dacron grafts were used exclusively from 1969 to 1979, and PTFE from 1979 to 1980. Cumulative patency for Dacron axillobifemoral grafts was 97 +/- 3% at 32 months (73 +/- 21% at 42 months). Patency in both unilateral and bifemoral grafts was significantly increased by thrombectomy. Dacron and PTFE axillobifemoral graft patency was not significantly different. Perioperative mortality was 8% in a group of patients whose survival rate at four years was only 50 +/- 10% from associated disease. Axillobifemoral grafting presents an alternative to aortoiliac reconstruction in elderly patients with severe associated disease in whom the risk of anatomic bypass is prohibitive.