Management of lower limb ischemia during operative repair of acute type a aortic dissection by distal crossover grafts: a case series

Abstract Objective: To describe our experience of nine patients with extra-anatomical bypass for clinically ischemic distal limb during repair of acute Type A aortic dissection (ATAAD). Methods: We retrospectively examined a series of nine patients who underwent surgery for ATAAD. We identified a subset of the patients who presented with concomitant radiographic and clinical signs of lower limb ischemia. All but one patient (axillobifemoral bypass) underwent femorofemoral crossover grafting by the cardiac surgeon during cooling. Results: One hundred eighty-one cases of ATAAD underwent surgery during the study period with a mortality of 19.3%. Nine patients had persistent clinical evidence of lower limb ischemia (4.9%) and underwent extra-anatomical bypass during cooling. Two patients underwent additional fasciotomies. Mean delay from symptoms to surgery in these nine patients was 9.5 hours. Two patients had bilateral amputations despite revascularisation and, of note, had long delays in presentation for surgery (> 12 hours). There were no mortalities during these inpatient episodes. Outpatient radiographic follow-up at the first opportunity demonstrated 100% patency. Conclusion: Our experience suggests that, during complicated aortic dissection, limb ischemia may have a devastating outcome including amputation when diagnosis and referral are delayed. Early diagnosis and surgery are crucial in preventing this potentially devastating complication.

Public misperceptions about transmission of hepatitis B virus in Singapore

<p><b>INTRODUCTION</b>Hepatitis B virus (HBV) infection is endemic in Asia. Good public knowledge on disease transmission is one way of controlling spread of HBV. We aimed to study the general knowledge on HBV among the general public in Singapore, which is moderately prevalent with HBV.</p><p><b>MATERIALS AND METHODS</b>Before conducting a public education seminar on liver diseases, a 16-point questionnaire survey was conducted among the participants. Misperceptions (if any) were identified, and factors associated with knowledge score were analysed by multivariate analysis.</p><p><b>RESULTS</b>One hundred and ninety-two subjects completed the questionnaire. The mean age was 52 years, 78 (41%) were male, 183 (95%) were Chinese, 17 (9%) were known hepatitis B carriers and 73 (38%) had completed college education. The mean knowledge score was 10.7 (out of a maximum of 16). Most misperceptions were in the category of HBV transmission. At multivariate analysis, having college education was the only independent factor associated with a high knowledge score.</p><p><b>CONCLUSION</b>Although HBV infection is moderately prevalent in Singapore, many misperceptions existed among the general public, especially on the mode of transmission. Better education was related to better knowledge of HBV. Further public education should be targeted to clear the misperceptions identified, and be specifically targeted to the less educated.</p>