Estado Hiperosmolar

Emerg Med Clin N Am 23 (2005) 629–648

Hyperosmolar Hyperglycemic State
Bruce W. Nugent, MD*
Division of Emergency Medicine, Spectrum Health-Butterworth, 100 Monroe NW, MC-49, Grand Rapids, MI 49503, USA

As the prevalence of diabetes mellitus escalates, emergency medicine practitioners will continue to see increasing numbers of patients with complications of uncontrolled hyperglycemia.Hyperosmolar hyperglycemic state (HHS) represents one of the two most serious acute metabolic complications of diabetes mellitus and is a life-threatening emergency. HHS is the end result of a sustained osmotic diuresis, and is characterized by severe hyperglycemia, hyperosmolarity, and dehydration, but without significant ketoacidosis. Less common than the other critical hyperglycemic diabeticemergency, diabetic ketoacidosis (DKA), HHS carries a higher mortality rate, associated with serious concurrent illness. It is usually seen in older type 2 diabetics, but can present at any age, and in patients with type 1 diabetes mellitus. Hyperosmolar hyperglycemic state first was described in 1957, and the literature since has referred to this syndrome by many terms, including hyperosmolar nonketoticstate, hyperosmolar coma, hyperglycemic hyperosmolar syndrome, or nonketotic hyperosmolar syndrome [1]. Hyperosmolar hyperglycemic state is the nomenclature recommended by the American Diabetes Association (ADA), used here to emphasize that varying alterations in sensorium less than coma are usually present and that HHS may occur with some degree of ketosis and acidosis [1–3]. Diagnostic featuresof HHS include the following [2]:  Plasma glucose level of 600 mg/dL or greater  Effective serum osmolality of 320 mOsm/kg or greater  Profound dehydration (typically 8 to 12 L) with elevated serum urea nitrogen (BUN):creatinine ratio  Small ketonuria, absent to low ketonemia  Bicarbonate greater than 15 mEq/L  Some alteration in consciousness
* 1792 Tahoe Pine Drive Southwest, GrandRapids, MI 49509, USA. E-mail address: nugentbw@cs.com 0733-8627/05/$ - see front matter Ó 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.emc.2005.03.006 emed.theclinics.com

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Hyperosmolar hyperglycemic state often is reviewed together with DKA because of similarities in pathogenesis and treatment approach. Many experts view these as two extremes on the spectrum ofdecompensated diabetes, differing from each other by the magnitude of hyperglycemia, the severity of acidosis/ketonemia, and the degree of dehydration [4–7]. Both disorders can occur in type 1 and type 2 diabetes mellitus, and up to one third of patients with decompensated diabetes share features of both DKA and HHS [4,5]. Important distinctions, however, exist in pathogenesis, clinical presentation, andtreatment between these disease states. This article focuses on the emergency department (ED) evaluation and management of HHS.

Emergency department presentation Epidemiology In 2002, an estimated 6.3% of the US population (about 18.2 million people) had diabetes. Type 2 diabetes mellitus accounts for 90% to 95% of cases, and people 65 years or older make up almost 40% of all persons with diabetes[8]. The prevalence of type 2 diabetes mellitus is increasing dramatically and parallels the epidemic of obesity. Blacks, Hispanics, and Native Americans are affected disproportionately. Type 2 diabetes mellitus now accounts for as much as half of newly diagnosed diabetes in children ages 10 to 21 years, depending on the socioeconomic and ethnic composition of the population [9,10]. Hyperosmolarhyperglycemic state occurs primarily in patients with type 2 diabetes mellitus, although that diagnosis may not have been known previously. In 30% to 40% of cases, HHS is the initial presentation of a patient’s diabetes [11,12]. HHS is significantly less common than DKA. The incidence of HHS is less than 1 case per 1000 person-years, compared with DKA, which occurs at a rate of 4.6 to 8 cases per...