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253.e2 Diabetes, Hyperosmolar Hyperglycemic State

Diabetes, Hyperosmolar Hyperglycemic State Client Education
Sheet
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BASIC INFORMATION
• Altered neurologic status (e.g., convulsions,
hypophosphatemia, and hypernatremia) can
ataxia, muscle twitching, nystagmus, lethargy, abnormalities (hyperkalemia or hypokalemia,
Definition coma) be seen.
• A hyperosmolar hyperglycemic state (HSS) is • Decreased body condition score common • Urinalysis: ± ketones (ketones present in
a life-threatening but uncommon metabolic • Bradycardia if hyperkalemia is present ≈30%); may see pyuria, bacteriuria (cystitis)
state characterized by marked hyperglycemia • ± Fever • Ketones can be measured in serum, plasma,
and hyperosmolarity and resulting from or urine.
uncontrolled diabetes mellitus (DM). Etiology and Pathophysiology ○ Although two ketone bodies formed
• Although most often identified in animals • An absolute or relative reduction in circula- in DKA (acetone and acetoacetate) are
lacking ketone production (i.e., hyperosmolar ting insulin combined with increased coun- readily detected on a urine dipstick by the
nonketotic [HNK] diabetes), HHS can also terregulatory hormones is key to development nitroprusside reaction, the predominant
occur concurrently with diabetic ketoacidosis of HHS and DKA. ketone body (beta-hydroxybutyrate) is not
(DKA). In other words, animals with HSS • Ketones are not produced if sufficient insulin detected.
may or may not have ketosis. is present to inhibit lipolysis and ketogenesis • Urine culture and susceptibility: rule out
(as in type II DM) or when hyperosmolarity secondary urinary tract infection
Synonyms inhibits lipolysis, thereby limiting the amount • Additional diagnostics, including thoracic
Hyperosmolar nonketonuric (HNK or HONK) of free fatty acids available for ketogenesis. or abdominal imaging, may be necessary
diabetes mellitus, hyperosmolar nonketotic • In people, HNK is more common in type II based on clinical signs to rule out concurrent
diabetes DM; although insulin is deficient, there is diseases.
enough to inhibit lipolysis and ketogenesis
Epidemiology but not enough to prevent hyperglycemia. Advanced or Confirmatory Testing
SPECIES, AGE, SEX Cats are more likely than dogs to have • Marked increase in serum osmolality (usually
• More common in cats than dogs but occurs residual insulin secretion despite being > 340 mOsm/kg; typical reference range is
in both species. diabetic, perhaps explaining why HNK is 285-308 mOsm/kg for cats and dogs)
• Usually middle-aged to older pets more common in cats than dogs. ○ Can be measured or calculated
• Hyperosmolarity may decrease lipolysis, ○ Calculated: Osm = 2(Na + K) + [Glu/18]
GENETICS, BREED PREDISPOSITION limiting the amount of free fatty acids + [BUN/2.8]
Australian terrier, Samoyeds, Bichon frisé, available for ketogenesis.
standard and miniature schnauzers, miniature • Depressed mental status in HHS patients TREATMENT
and toy poodles, and spitz dogs are at increased is attributed to hypernatremia and hyperos-
risk for DM. molarity-induced dehydration of the brain Treatment Overview
parenchyma. Although measured sodium Rehydration and correction of electrolyte
RISK FACTORS levels are rarely dramatically increased with disturbances is the initial step in treating HHS
• Unregulated DM HHS, a corrected sodium level in relation patients. After this is accomplished, insulin
• Concurrent infection or illness in diabetic to hyperglycemia can be high enough to therapy is initiated to gradually decrease blood
patient indicate cellular dehydration and neurologic glucose (BG) concentrations.
disruption (see below).
ASSOCIATED DISORDERS Acute General Treatment
• DKA DIAGNOSIS • Rehydration with isotonic crystalloid fluids
• Kidney failure (acute or chronic) is essential. Isotonic saline (0.9% NaCl) is
• Cardiac disease, including congestive heart Diagnostic Overview typically used because it addresses fluid
failure Diagnosis of HHS is based on documenta- deficits and replaces glucose with sodium
• Neoplasia tion of hyperglycemia (typically extreme) and in the extracellular space, preventing a rapid
• Gastrointestinal (GI) disease hyperosmolarity; if ketones are absent, the term shift in osmolality. Isotonic saline can also
• Pancreatitis HNK also applies. HHS can occur in patients help prevent overly rapid reduction in serum
• Respiratory disease with newly recognized DM or in patients with sodium (do not lower Na by more than
• Acromegaly (cats) known DM. 1 mEq/L/h)
○ Can begin with fluid bolus of 20 mL/
Clinical Presentation Differential Diagnosis kg (cat) or 30 mL/kg (dog) to address
HISTORY/CHIEF COMPLAINT • Vomiting, inappetence, lethargy can be due to shock and hypovolemia. This bolus may
Animals may (≈50%) or may not have a a concurrent disease (e.g., DKA, pancreatitis, be repeated based on clinical response
history of previously recognized clinical signs severe infection) (e.g., capillary refill time, blood pressure,
of DM (i.e., polyuria/polydipsia, polyphagia, • Depressed mental status: intracranial disease mentation status)
and weight loss). Historical findings related (e.g., neoplasia, granulomatous inflamma- ○ After crisis of vascular volume is addressed,
specifically to HHS include: tion, infarct), hypoglycemia, other severe correct dehydration deficit. Dehydration
• Inappetence illness deficit is calculated as body weight (kg)
• Vomiting × % estimated dehydration (as decimal);
• Lethargy (often severe) Initial Database for example, a 10-kg animal that is 8%
• Behavioral changes • CBC: neutrophilia as part of stress leukogram dehydrated = 10 × 0.08 = 0.8 L deficit.
• Rarely, coma related to HHS or indication of a secondary ○ Correct one-half of deficit within 12 hours
infection. Moderate anemia if significant and remainder over the next 24 hours.
PHYSICAL EXAM FINDINGS hypophosphatemia is present. ○ After restoration of vascular volume,
• Severe dehydration (>8%) • Serum chemistry: hyperglycemia (often fluid type may be changed to a more
• Depressed or obtunded mentation > 800 mg/dL), azotemia, and electrolyte physiologic isotonic fluid (e.g., lactated
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