Elsevier

Journal of Critical Care

Volume 30, Issue 5, October 2015, Pages 1021-1024
Journal of Critical Care

Prediction
Preanesthetic mortality prediction in diabetics undergoing major lower limb amputation at a tertiary referral hospital: Implications of preoperative echocardiographic and laboratory values

https://doi.org/10.1016/j.jcrc.2015.04.122Get rights and content

Abstract

Purpose

Cardiac comorbidities in patients undergoing amputation due to diabetic foot ulcer are associated with high mortality rates. The authors investigated whether preanesthetic echocardiographic and laboratory values can predict inhospital mortality in type II diabetes patients undergoing major lower limb amputation under spinal anesthesia.

Methods

The archived medical records of 215 patients were retrospectively reviewed. Demographic data and preoperative laboratory and transthoracic echocardiographic values were analyzed by multivariate logistic regression for factors independently associated with inhospital mortality.

Results

Of the 215 patients, 12 died in hospital after amputation. Preoperative hemoglobin level (hazard ratio, 0.082; 95% confidence interval, 0.013-0.509; P = .007) and left ventricular ejection fraction (hazard ratio, 0.874; 95% confidence interval, 0.779- 0.981; P = .023) were found to be significant predictors of inhospital mortality.

Conclusions

Preoperative hemoglobin level and left ventricular ejection fraction are highly correlated with inhospital mortality in type II diabetes patients undergoing major lower extremity amputation under spinal anesthesia.

Introduction

In diabetes, the prevalence of lower extremity amputation is high at 0.21% to 1.37% and that of foot ulcer is 1.0% to 4.1% [1]. Patients who undergo amputation for diabetic foot ulcer have an exceptionally low 5-year survival rate (up to 23%), and survival in this patient population is highly correlated with previous cardiac comorbidity (hazard ratio, 2.16) [2], [3]. Studies on the topic have reported that advanced age, comorbid cardiovascular disease, absence of revascularization, and renal impairment are major determinants of survival after amputation for a foot ulcer in diabetic patients [2], [4]. However, few studies have addressed prognostic factors other than the aforementioned clinical histories after major lower limb amputation in this population. Considering the fact that cardiovascular mortality is 4.4-fold higher in diabetic patients than in nondiabetic subjects [5], it is somewhat surprising that no prognostic factors that predict mortality and morbidities have been suggested in diabetic patients undergoing major lower limb amputation.

Echocardiographic findings regarding cardiac anatomy and function have been suggested to be good predictors of 30-day and long-term cardiovascular outcome after open vascular surgery in patients with asymptomatic left ventricular (LV) dysfunction [6]. In addition, some perioperative laboratory findings aid the management of diabetic foot amputation [7], [8].

We conducted this retrospective analysis to access the abilities of preanesthetic echocardiographic and laboratory values to predict mortality and cardiovascular morbidity in type II diabetes patients undergoing major lower limb amputation under spinal anesthesia.

Section snippets

Data collection

After obtaining approval from our ethics committee, we retrospectively reviewed the medical records of 310 patients archived at the Gachon University Gil Medical Center, a 1400-bed tertiary referral hospital. Records were searched using the keywords “diabetes mellitus plus amputation.” Of the 310 patients initially identified, 95 subjects were excluded from the analysis due to traumatic amputation, minor amputation, or wound dressing under local anesthesia. Accordingly, the records of 215

Demographic data, preoperative histories, and postoperative outcomes

Patient demographic data are presented in Table 1. Mean duration of diabetes was 186 months, and all 215 patients had at least 1 comorbidity. Of the 79 CAOD patients, 49 were incidentally diagnosed during a preoperative evaluation. Nine patients had a history of myocardial infarction (MI), and 21 patients had a history of angina pectoris. Three patients had experienced an ischemic heart attack within 3 months before operation. Nine patients had been diagnosed with congestive heart disease. One

Discussion

In the present study, we found the mortality rate after major lower limb amputation for a diabetic foot ulcer in a tertiary referral hospital was 5.6% (12/215) and that preoperative hemoglobin and LVEF predicted inhospital mortality. In particular, a hemoglobin level of 9.55 g/dL and an LVEF of 52% were found to be optimal threshold values for predicting mortality after major lower limb amputation in type II diabetes. To the best of our knowledge, this is the first study conducted on the

No external funding was received for this study, and the authors have no potential conflict of interest to declare.

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