Partial versus complete arterial transection, fact versus fancy.

Traditionally, hemorrhage from the partially transected artery exceeds that from its completely divided counterpart. The clinical significance of this distinction is pertinent to the control of the hemorrhage in the field as well as in the operating room. To test the hypothesis the femoral arterial blood flow (Q) of seven anesthetized (pentobarbital, 30 mg/kg, IV) dogs, whose average weight was 19.5 +/- 0.9 kg, was measured before and after partial (25%, 75%) and complete transection of the artery distal to the transducer of an electromagnetic blood flow meter amplifier. Systemic arterial pressure (P) was recorded. Control Q was 72 +/- 14 (S.E.) ml/min, control P was 119 +/- 9 mmHg. Flow increased to 369 +/- 24 ml/min when partial laceration (25% lumenal diameter) was accomplished sharply; this increase was significant (P = 1.7 X 10(-6]. When the arterial division was near completion (75% lumenal transection), Q was 358 +/- 30 ml/min. This value was not significantly different (P = 0.80) from the value that resulted from complete transection of the femoral artery (320 +/- 41 ml/min). Arterial pressure fell transiently (11.5 +/- 1.7, 13.5 +/- 1.6, and 13.9 +/- 2.1 mmHg respectively) as a result of each injury but the apparent differences were not significant (P = 0.25). These observations from canine experimentation indicate that hemorrhage from the partially severed femoral artery is indistinguishable from that which results from its complete transection. In view of these findings in dogs, traditional concepts regarding such injuries in man should be viewed as unproven speculation.

A nonheparinized muscle model for studies of ischemia-reperfusion injury.

An understanding of the basic metabolic, functional, and histologic features of skeletal muscle injury secondary to ischemia and reperfusion has thus far been hampered by the lack of an adequate animal model. We have developed an in vivo isolated skeletal muscle preparation amenable to ischemia-reperfusion studies and the investigation of therapeutic modalities. The model is autoperfused and, most importantly, nonheparinized. The use of a nonheparinized model is essential following the work of Hardaway, recently confirmed by Fry, showing that alterations of flow in the shock state occur when heparin is used, invalidating other models as true replicas of clinical situations. The gracilis muscle in the canine hindlimb and its contralateral control are isolated on their neurovascular pedicles after detachment of fascial boundaries and meticulous ligation of all collateral vascular supply. Prolonged arterial occlusion can be accomplished by clamping proximal and distal to the point of origin of the gracilis artery from the superficial femoral artery. In a similar fashion, occlusion above and below the gracilis vein is effected intermittently to collect venous efluent during reperfusion. Preliminary studies of 100 muscle preparations subjected to 3 or 15 hr of ischemia, followed by 2 hr of reperfusion, demonstrate depression of oxygen utilization of 5% of control values during early reperfusion with improvement to 30% of control values over 2 hr. Contractility, abolished during ischemia, returns to 20% of control values after 2 hr of reperfusion.

A comparison of isobutyl 2-cyanoacrylate glue, fibrin adhesive, and oxidized regenerated cellulose for control of needle hole bleeding from polytetrafluoroethylene vascular prostheses.

Prolonged anastomotic and needle hole bleeding from synthetic vascular prostheses is a common surgical problem in heparinized patients and in the patient with a coagulopathy. The relative effectiveness of various hemostatic agents has not previously been determined by controlled comparisons. In this study 6 mm polytetrafluoroethylene (PTFE) vascular prostheses were used to perform carotid-carotid and femorofemoral bypasses in eight heparinized dogs. The relative effectiveness of isobutyl 2-cyanoacrylate, fibrin adhesive, and oxidized regenerated cellulose was determined by application of these hemostatic agents to three sources of bleeding: arterial-PTFE anastomoses, PTFE-PTFE anastomoses, and 18-gauge needle holes in PTFE vascular prostheses. The mean time to hemostasis (MTH) was determined for each hemostatic agent. Although application of isobutyl 2-cyanoacrylate resulted in the shortest MTH in each experimental group, the reported inflammatory response that it induces and its possible carcinogenicity limits its availability for clinical use. Application of fibrin adhesive prepared from single-donor hepatitis-screened plasma resulted in a significantly shorter MTH in each experimental group when compared with oxidized regenerated cellulose. We recommend clinical use of fibrin adhesive to control needle hole and anastomotic bleeding from PTFE vascular prostheses.

Tuberculous retroperitoneal lymphadenopathy mimicking metastatic pancreatic carcinoma.

A case of retroperitoneal lymphadenopathy of tuberculous origin is reported. Despite clear representation of retroperitoneal lym-phadenopathy by abdominal ultrasonography and computerized tomography (CT), fine-needle aspiration was inconclusive. Exploratory laparotomy was necessary to make the diagnosis. Nonsurgical diagnosis of this entity continues to be a challenge.