Acute lower limb ischemia is a frequent complication of severe diabetic hyperosmolarity

Abstract

Aim To describe the outcome of intensive care unit (ICU) patients admitted with a hyperglycaemic hyperosmolar non-ketotic syndrome (HHNS), with a specific analysis of precipitating conditions and complications including lower limb ischemia. Methods Retrospective review of patients admitted in a university-hospital ICU for HHNS. Results Seventeen consecutive patients (9F/8M, age: 75 years [57–81] (median [25–75% percentiles], Glasgow Coma score: 13 [12–14]) were admitted for HHNS over an 8-year period (1998–2005). On admission, the blood glucose level was 40.0 mmol/l [26.3–60.8], the corrected serum sodium concentration 167 mmol/l [158–174], and the calculated plasma osmolarity 384 mosmol/l [365–405]. All the patients presented with renal failure due to severe dehydration. An infection was identified as the precipitating factor in 8/17 cases. Three (18%) patients died in the ICU. Non-survivors were significantly older than survivors ( P = 0.02). Using univariate analysis, no other parameter measured on admission was related to mortality. Four patients (24%) presented with lower limb ischemia. They had a significantly more elevated blood urea nitrogen ( P = 0.03), creatinine phosphokinase level ( P = 0.04), and leukocyte count ( P = 0.02). The bilateral, symmetrical, and distal extremity involvement suggested diminished blood flow due to hyperviscosity, hypotension, vasoconstrictors, or cholesterol emboli rather than a proximal arterial obstruction as causative mechanisms. No patient was treated surgically. Ischemia reversed with fluid loading and resulted in toe dry digital necrosis. Conclusion HHNS is a rare but life-threatening cause of ICU admission. There is a high incidence of lower limb ischemia in HHNS patients, which may be related to dehydration and blood hyperviscosity.