Q: How much is the average fluid deficit in Hyperosmolar hyperglycemic state (HHS), previously known as hyperosmolar hyperglycemic nonketotic coma (HHNK)?

Answer:  About 9 liters

According to the consensus statement published by the American Diabetes Association, diagnostic features of HHS may include

• Plasma glucose level of 600 mg/dL or greater
• Effective serum osmolality of 320 mOsm/kg or greater
• Profound dehydration, up to an average of 9L
• Serum pH greater than 7.30
• Bicarbonate concentration greater than 15 mEq/L
• Small ketonuria and absent-to-low ketonemia
• Some alteration in consciousness

Reference:

Kitabchi AE, Umpierrez GE, Murphy MB, Kreisberg RA. Hyperglycemic crises in adult patients with diabetes: a consensus statement from the American Diabetes Association. Diabetes Care. Dec 2006;29(12):2739-48