Can Albumin Administration Cause Hypernatremia?
Albumin administration does not directly cause hypernatremia; in fact, in cirrhotic patients with ascites, long-term albumin therapy actually improves hyponatremia and reduces episodes of moderate hyponatremia.
Evidence from Cirrhosis and Ascites Management
The most robust evidence comes from the cirrhosis literature, where albumin is extensively studied:
Long-term albumin administration in cirrhotic patients with ascites significantly improves hyponatremia, with a normalization rate of 45% versus 28% with standard medical treatment at 1 month (P = 0.042) 1
Albumin reduces the incidence of moderate hyponatremia in outpatients with cirrhosis and ascites, with an incidence rate ratio of 0.245 (95% CI 0.167-0.359, P < 0.001) 1
In the ANSWER trial, patients randomized to weekly albumin infusions had less hyponatremia compared to controls, not more 2
Mechanism: Why Albumin Improves Rather Than Worsens Sodium Balance
Albumin improves effective circulating volume in cirrhotic patients, reducing non-osmotic vasopressin release and improving free water excretion 3
In severe hypoalbuminemia with hyponatremia, albumin infusion dramatically increases plasma sodium concentrations and serum osmolality, with concomitant fall in urinary osmolality 4
The oncotic properties of albumin help redistribute fluid from interstitial to intravascular space, improving renal perfusion and sodium handling 5
Clinical Context: When Hypernatremia Occurs in ICU Patients
While albumin itself does not cause hypernatremia, critically ill patients receiving albumin may develop hypernatremia through unrelated mechanisms:
Hypernatremia in ICU patients develops from excessive sodium administration (sodium bicarbonate, mannitol) combined with inadequate free water replacement 6
Risk factors for ICU-acquired hypernatremia include sepsis, renal dysfunction, hypoalbuminemia (91% versus 55% in controls), and use of sodium-containing medications 6
Hypoalbuminemia is associated with hypernatremia as a marker of critical illness, not as a cause-and-effect relationship with albumin therapy 6
Practical Implications
Albumin solutions contain sodium (20% albumin contains approximately 130-160 mEq/L sodium depending on formulation), but this is comparable to normal saline and does not independently drive hypernatremia 5
When hypernatremia develops in patients receiving albumin, look for other causes: excessive sodium bicarbonate, mannitol, inadequate free water replacement, or polyuria with hypotonic fluid losses 6, 7
Monitor sodium levels during albumin therapy, but recognize that albumin administration in cirrhotic patients typically improves rather than worsens sodium balance 1