Approach
• Careful hx: Understand whether pt has had excessive fluid loss or inadequate intake
• Attempt to quantify fluid deficit
• Check fingerstick blood sugar to r/o hypoglycemia, electrolytes
History
• Excessive fluid loss (V/D, sweating, polyuria, diuretic/laxatives, bowel regimen), inadequate intake (debilitated, institutionalized, NM d/o, H&N pathology), altered thirst mechanism (intoxication, systemic illness, malignancy, antipsychotic use)
Findings
• ↑ HR w/ standing (Δ >20 beats/min lying → standing); 75% sens & spec
Evaluation
• CBC (hemoconcentration), Chem 7 (↓ bicarb, ↑ BUN/Cr, abnl Na, K), ECG abnl
• UA: Ketones, hyaline casts, spec grav >1.02: Uroconcentration, >1.03: Severe dehydration
Treatment
• Initial fluid resuscitation w/ NS or LR (avoid NS if concern for hyponatremia), then tailor to electrolyte abnlty/pathology (labor: Nonglucose IVF, malnourishment: D5 NS)
• nl LV fxn: 2–3 L NS, follow clinical sxs, VS, UOP
• Compromised LV fxn: 500 cc/h, watch pulmonary status (O2 sat, SOB)
• Consider antiemetic if N/V is contributing to dehydration
Disposition
• Home once dehydration adequately treated unless concerning electrolyte abnormalities, pt able to maintain hydration status
• Consider care coordination/placement if pt lives alone & unable to hydrate self
Pearls
• Up to 30% of healthy pts are orthostatic w/o dehydration (βBs, autonomic Dysfxn (DM))
• Oral rehydration w/ glucose to facilitate intestinal absorption of Na & water if pt tolerates, “recipe” is 2 tbl sugar : 0.5 tsp salt : 1 quart water
• Healthy adults tolerating PO rarely require IVF & PO rehydration is usually adequate
