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.

Tube thoracostomy and trauma--antibiotics or not?

Controversy persists regarding the use of antibiotics in association with t tube thoracostomy for trauma patients. We conducted a prospective randomized study of patients requiring tube thoracostomy for pneumo- and/or hemothorax complicating blunt or penetrating thoracic trauma in an attempt to assess the efficacy of prophylactic antibiotic therapy. Fifty-eight patients were included in the study. The control group (Group I) included 28 patients who received no antibiotic therapy: the experimental group (Group II) included 30 patients who received cefoxitin (1.0 gm IV q 6 h) commencing before tube thoracostomy and terminating 12 hours after its removal. The incidence of infectious complications (pneumonia and/or empyema) was recorded. Among the patients not receiving antibiotics, eight of 28 (29%) developed infectious chest complications. Of the patients receiving antibiotics, there was one infectious complication (3%). This difference is statistically significant (p = 0.0227). Cultures demonstrated significant conversion from negative to positive both within each group and between groups. The organism most commonly recovered was S. aureus. Our findings strongly suggest that patients requiring tube thoracostomy for trauma, whether blunt or penetrating, should receive the benefit of systemic prophylactic antibiotic therapy.