Vascular Surgery Unit Research Articles

Postoperative haemorrhage following aortic aneurysm repair

Between 1988 and 1993, 17 (3%) out of a total 654 patients underwent reoperation for control of haemorrhage following repair of abdominal aortic aneurysm in a vascular surgery unit. The first operation was performed for rupture in 12 cases and electively in five. The incidence of reoperation for postoperative bleeding was 1.7% following elective operation and 3.3% following emergency operation. Case-controls, matched for sex and primary operation, were identified. The mortality rate in those requiring reoperation was 58% compared with 23% in the control group (p = 0.037). Seven patients suffered progressive deterioration and died in the early postoperative period. Of the remaining ten patients, four suffered unexpected serious complications; two a fatal cerebro-vascular accident (CVA), one a fatal myocardial infarction (MI) and the fourth a non-fatal CVA. The patients requiring reoperation had greater blood loss (p < 0.05), greater transfusion requirements and lower core temperatures (p < 0.05) at the end of their first operation than the control group. All except one of the patients who bled had evidence of coagulopathy and had lower platelet counts than the control group both before and after the first operation. At reoperation there were multiple minor bleeding points in 11 patients, no active bleeding points in two patients and a discrete bleeding point in four patients. In conclusion, re-operation for control of postoperative haemorrhage is an uncommon complication which is strongly associated with coagulopathy, may predispose to "rebound" postoperative thrombotic episodes, and carries a poor prognosis.

Morphological Study of the Valvular Distribution in the Long Saphenous Vein

Objective: To measure the distribution of valves in the long saphenous vein. Design: Morphological study of the intervalvular distance of the long saphenous vein. Setting: Department of Morfología, Facultad de Ciencias de la Salud (Universidad de Las Palmas de Gran Canaria, Spain) and Academic Vascular Surgery Unit, St Mary's Hospital, London, UK. Material: Twenty lower extremities from adult cadavers with no evidence of lower limb venous disease. Methods: Anatomical dissection of the long saphenous vein, with accurate measurement of valve distribution. Results: There were on average 8.7 valves in the long saphenous vein, with 6.3 above the knee and 2.4 below the knee. Conclusion: Contrary to classical anatomical texts on this subject there are more valves in the long saphenous vein in the thigh than in the calf.

Detection of intracranial emboli in patients with carotid disease

Transcranial Doppler emboli signal detection has been reported in several patient groups, including patients with symptomatic internal carotid artery stenosis. The potential of this technique in assessing embolic risk and selecting patients for surgery was examined in this study. Selected patients with symptomatic internal carotid artery stenosis underwent combined extracranial and transcranial Doppler study in the Vascular Surgery and Neurovascular Unit. Patients and normal controls were monitored with transcranial Doppler over both middle cerebral arteries. Severity of carotid disease was diagnosed with colour Duplex ultrasound examination or angiography. Selected patients underwent cranial computed tomography and transthoracic echocardiography. Patients undergoing carotid endarterectomy were re-examined one month after surgery. Fifty symptomatic patients, six asymptomatic patients and 30 normal controls were examined. Carotid disease was unilateral in 34 and bilateral in 22 cases. Emboli signals were detected in 94% of patients. The emboli signal count in patients with unilateral carotid stenosis was significantly higher in the middle cerebral artery distal to the stenosed internal carotid compared to the contralateral middle cerebral artery [14 (10-22) versus 2 (0-7) signals per hour, median and 95% confidence intervals, p < 0.001] and in symptomatic compared to asymptomatic cerebral hemispheres [15 (11-21) versus 4 (2-9) signals per hour, p < 0.001]. Emboli were detected in the contralateral middle cerebral artery in 40% of patients with unilateral carotid disease, in 85% of whom an additional embolic source was identified. No emboli signals were detected after carotid endarterectomy distal to the operated internal carotid, or in any of the normal controls. In conclusion, intracranial emboli signals are common in patients with carotid stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Nosocomial Infection Surveillance in a Vascular Surgery Unit

An epidemiological nosocomial infection surveillance program was conducted in the Vascular Surgery Unit of Purpan University Hospital, Toulouse, France, involving 389 patients hospitalized between June 1 and November 30, 1988. The methodology and inclusion criteria used were those of the Centers for Disease Control of Atlanta. Twenty-six patients had 30 nosocomial infections according to these criteria, a prevalence of 6.7% and an incidence of 5.6%. These patients were hospitalized for 485 of a total of 4317 days; bed occupation due to infection was 11.23%. Of the 30 infections, the most common were 13 (43.5%) urinary tract infections and six (20%) operative wound infections. E. coli (8 isolates) and Staphylococcus aureus (7 isolates) were the most frequently encountered offending microorganisms. A case-control study showed that mean hospitalization time was increased by 11 days (p less than 0.001) in infected patients and that antibiotics were used four times as often in these patients (p less than 0.001). Urinary tract infection represented 50% of nosocomial infections in our study. The prevalence and incidence of wound infection was 20% and 8%, respectively. Nosocomial infection always occurred in patients already infected or who were debilitated. Nosocomial infections prolonged hospitalization by 57%.