Cyclosporine toxicity associated with allopurinol.
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Biomedical subjects
Publications and source records attributed to S L Stevens.
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BACKGROUND: During a 6-year period, 349 in situ saphenous vein bypass grafts were performed for limb salvage by three surgeons. METHODS: Outflow anastomoses were constructed to the infrageniculate popliteal (25%), posterior tibial (20%), peroneal (20%), anterior tibial (19%), and dorsal pedal arteries (7%). Mean patient age was 70 1/2 years. RESULTS: The 30-day mortality rate was 3.2%, and 19% died during the ensuing 68-month interval. At 1, 24, and 60 months primary graft patency was 89%, 77%, and 74%, secondary graft patency was 91%, 80%, and 78%, and cumulative limb survival was 94%, 88%, and 84%, respectively. Cumulative patency rates at 60 months depending on outflow site were as follows: popliteal (85%), anterior tibial (80%), posterior tibial (70%), dorsal pedal (68%), and peroneal (60%). Patency at the peroneal position was significantly inferior to that of other infrapopliteal sites combined (p less than 0.05). Cumulative limb survival at 60 months, according to outflow site, was as follows: popliteal (95%), anterior tibial (85%), posterior tibial (78%), dorsal pedal (73%), and peroneal (67%). There was no significant difference in limb salvage among infrapopliteal outflow sites. However, patency rates and limb salvage were significantly better for the popliteal outflow site than the infrapopliteal outflow sites (p less than 0.01). CONCLUSIONS: (1) A 5-year graft patency rate of 78% and a limb salvage rate of 84% are achievable, (2) peroneal bypass is associated with a lower rate for graft patency but not limb salvage, and (3) popliteal bypass has the best graft patency and limb salvage rates.
To improve hemostasis and avoid the complications of perihepatic packing, a technique of hepatic tamponade using total mesh wrap is reported. The method is geometrically, technically and mechanically feasible and appears to be effective in controlling severe parenchymatous bleeding.
This study examined a mesh wrap technique that provides effective hepatic tamponade and clinical experience with the technique in 6 patients is reported. Technical feasibility and effectiveness were investigated in 8 miniature swine. The animals were divided into two groups: group A (n = 4), control animals; stellate liver lacerations without mesh wrap or other measures for hemostasis, and group B (n = 4); stellate liver laceration with synthetic absorbable mesh wrap applied for hepatic hemostasis. Except for mesh application, all variables were held constant for both groups. All animals in the control group died within 20 to 120 minutes (mean: 65 minutes). All animals in group B survived (p = 0.029). The livers were harvested for gross and microscopic examinations. No abscess, bile leak, or hematoma was noted. Clinically, total mesh wrapping was attempted in 6 patients with blunt exsanguinating liver injuries. The technique failed intraoperatively in two patients with juxtacaval lacerations and hepatic vein avulsion injuries. One patient with a bilobar gunshot wound died later of sepsis. In three patients with bursting injuries, the technique successfully controlled bleeding and resulted in long-term survival. In conclusion, the total hepatic mesh wrap (1) is geometrically, technically, and mechanically feasible, (2) was not associated with complications in this series, and (3) can effectively secure hemostasis following parenchymal liver injury.
Small bowel injuries are becoming more commonplace. Difficult to diagnose and treacherous when missed, small bowel injuries should be searched for assiduously in all patients at risk. Use of DPL or CT scanning, coupled with a low threshold for exploration, improves the diagnosis and treatment of small bowel injuries. A delayed diagnosis results in a progressive septic insult and markedly increased mortality. Early diagnosis is the key. After addressing life-threatening problems, the operation should include a thorough and systematic exploration to identify all injuries. Sound surgical technique includes debridement of nonviable tissue, restoration of small bowel continuity, generous irrigation, and placement of enteral feeding catheters. By adhering to the preceding principles and by exercising meticulous postoperative care and maintaining a low threshold to reoperate, catastrophic complications can be avoided.
In immunologically defined National Institutes of Health miniswine, a segment of internal jugular vein was anastomosed to the carotid artery as an interposition graft. Patency of swine major histocompatibility complex matched, one haplotype mismatched, and complete mismatched veins was 9.8, 6.3, and 3.0 weeks respectively (p = 0.009). More than 90% of mismatched and 20% of matched allografts developed a positive crossmatch before occlusion (p = 0.006). The mixed lymphocyte response did not predict graft occlusion. Treatment of 10 swine with cyclosporine (10 mg/kg/day) did not significantly improve patency for one haplotype mismatched grafts. In haplotype mismatched veins, cryopreserved grafts occluded more rapidly than noncryopreserved grafts: mean 2.4 versus 6.3 weeks, respectively (p = 0.002). In all cryopreserved vein grafts, alloantibody appeared at or after graft occlusion rather than before occlusion as seen with fresh allografts (p = 0.046). The mean patency of cryopreserved versus fresh autografts was 3.3 and greater than 32 weeks, respectively (p = 0.004). In summary, these results indicate that (1) allograft patency is related to the degree of swine major histocompatibility complex match and development of cytotoxic alloantibodies; (2) moderate-dose cyclosporine does not prolong allograft patency nor suppress development of antibody; (3) cryopreservation may accelerate graft occlusion through nonimmunologic mechanisms.
Rapid fluid administration is the cornerstone of successful trauma resuscitation. Percutaneous insertion of catheter introducers has gained wide acceptance as a quick and reliable means of rapid intravascular volume expansion. Factors that affect rapid fluid resuscitation with these devices include catheter introducer kinking, the type and temperature of infusate, and diameter of co-apted administration tubing. Rates of flow through 8.5 French catheters from 0 to 80 degrees of catheter angulation were determined in vitro for various fluids (crystalloid, whole blood, diluted packed cells) and administration tubing of different sizes (regular IV tubing, blood tubing, and large-bore trauma tubing). The flow rate of crystalloid infusion through blood tubing was found to be approximately double that of regular IV tubing (316 cc/min vs. 160 cc/min), and trauma tubing had approximately three times the flow rate of blood tubing (805 cc/min). Warmed diluted packed cells could be infused almost twice as fast as cold whole blood (642 cc/min vs. 340 cc/min). Kinking of the catheter introducer, a heretofore poorly described phenomenon, halved the flow rate of fluids through large-bore trauma tubing (805 cc/min vs 350 cc/min) but had no effect when standard IV tubing was utilized. Piggybacking blood into an existing IV line instead of infusing it directly into the catheter can decrease blood flow 94% (340 cc/min vs. 20 cc/min). It is concluded that a large-bore catheter, by itself, does not guarantee high flow rates. Physician recognition of these concepts can result in improved resuscitation of hypovolemic patients.
Disk diffusion susceptibility tests for enterococci are frequently modified by adding 5% sheep blood (SB) to Mueller-Hinton agar; the performance standards from the National Committee for Clinical Laboratory Standards sanction this addition. Susceptibility testing of aminoglycoside antibiotics is not recommended for enterococci; in actual practice, however, some laboratories do include aminoglycoside antibiotics routinely, and others may test upon request or in selected situations. In examining 50 clinical isolates of enterococci, SB-enriched Mueller-Hinton agar frequently gave enlarged zone sizes that falsely indicated susceptibility (72% for gentamicin and tobramycin), with the average increase in zone size being 6.3 and 7.6 mm, respectively. Comparison agar dilution MICs demonstrated uniform resistance, with or without added SB. The effect was shown to be caused by heme in concentrations as low as 0.03 micrograms/ml, which, when combined with aminoglycoside antibiotics, caused a synergistic growth inhibition of the enterococci, resulting in larger aminoglycoside antibiotic zones. We postulate that the heme effect is related to a catalytic cleavage of intracellular H2O2 and resultant lipid peroxidation. No other organism or antimicrobial agent tested demonstrated a similar effect, although other investigators have shown a similar phenomenon with the broad-spectrum cephalosporins. Because enterococci grow well and give accurate susceptibility results on Mueller-Hinton agar without SB supplementation and because of the spectrum of definable problems with a number of antimicrobial agents, we recommend that enterococci routinely be tested without SB.
Lasers have been used for endoscopic gastrointestinal surgery at our institution since 1977. The argon and Nd-YAG lasers are valuable for coagulating upper gastrointestinal hemorrhage, arteriovenous malformations, and benign and malignant lesions, as well as a variety of anatomic anomalies. Between December 1977 and September 1983, 222 procedures were performed in 122 patients. Hospital charts were reviewed and a scale constructed to assess the results of treatment. When information was available, a comparison of transfusion requirements before and after laser therapy was made. Success was achieved in 84 percent of the patients regardless of initial diagnosis. Laser therapy was not effective in 12 patients (10 percent). In 27 patients with gastrointestinal atrioventricular malformations, transfusion requirements fell from a mean of 17 +/- 5.9 units in the year before laser therapy to 1 +/- 0.8 units in the year after laser phototherapy (p less than 0.01). Complications rarely occurred (6 percent of all procedures). There were no perforations of the gastrointestinal tract and only one death (0.8 percent) partially attributable to laser application. Endoscopic laser surgery is minimally invasive and can be performed on an outpatient basis without anesthesia. It is especially valuable in patients with a high operative risk.
The different allelic forms of nine non-Mhc alloantigen systems of the chicken were examined for developmental expression on erythrocytes isolated from embryos and young chicks. Polyclonal alloantisera raised against the different antigens were used to detect these antigens on the cell surface by hemagglutination as well as by indirect immunofluorescence. The developmental stage of initial expression on erythrocytes for each of the genetic systems investigated (i.e., A, E, C, D, H, I, K, L and P) varied from day 4 to day 14 of incubation. The different antigens of each system appeared simultaneously at a particular stage of development except for those of the I system, where the I8 allelic form appeared earlier than I2.
Femoral arterial pseudoaneurysms or arteriovenous fistulae may sometimes complicate percutaneous femoral artery catheterization procedures. Most surgeons recommend prompt operative repair because of the unfavorable natural history of pseudoaneurysms or arteriovenous fistulae secondary to violent or accidental arterial trauma. However, the natural history of catheterization-induced pseudoaneurysms and arteriovenous fistulae has not been well documented. Accordingly, we prospectively studied the natural history of 22 pseudoaneurysms, 8 arteriovenous fistulae, and 3 combined lesions, identified by duplex scan in 32 patients following trans-femoral cardiac, peripheral vascular, or vascular access arterial catheterization procedures. Angiographic procedures were performed with the use of 5-8F introducer sheaths. A femoral artery complication was significantly more likely to result from coronary balloon angioplasty (9/304; 3.0%) than from diagnostic cardiac catheterization (21/2476; 0.8%) (p less than 0.003; chi square). Fourteen patients (13 pseudoaneurysms, 1 combined pseudoaneurysm/fistulae) underwent surgical repair. Pain and/or enlarging hematoma resulted in repair within two days of the diagnosis in 8 patients. The need for chronic anticoagulation prompted elective repair in 2 patients. A pseudoaneurysm was repaired in one patient five days following catheterization when it became painful. In three stable patients, asymptomatic pseudoaneurysms were repaired electively during another surgical procedure. There were no operative deaths. One patients (7%) developed a wound infection postoperatively. Eighteen patients (19 arterial lesions: 9 pseudoaneurysms, 8 arteriovenous fistulae, 2 combined pseudoaneurysms/arteriovenous fistulae) with improving symptoms and stable physical signs were followed by serial clinical evaluation and duplex scans. Seventeen of 19 (89%) of these lesions resolved spontaneously within 5-90 days (mean 30.7 days).(ABSTRACT TRUNCATED AT 250 WORDS)