Hypophosphatemia after nontraumatic intracranial hemorrhage.

BACKGROUND: The aim of this study was to assess the incidence and contributing factors of hypophosphatemia and the association with poor long-term outcome after nontraumatic intracranial hemorrhage.

METHODS: This was a prospective, observational study of patients with nontraumatic intracranial hemorrhage (i.e., aneurysmal or perimesencephalic subarachnoid hemorrhage, or spontaneous intracerebral or intraventricular hemorrhage) treated in the intensive care unit (ICU) at our university hospital. Plasma phosphate concentrations were measured serially in 2-day sections during the 6 day study period. The ICU mortality was recorded, 3-month and 1-year outcomes were assessed using the Glasgow Outcome Scale.

RESULTS: One hundred patients were enrolled. The frequency of hypophosphatemia (Pi ≤ 0.65 mmol/l) was 70%. Chronic hypertension, acute hydrocephalus, and diffuse brain edema were more common in patients with hypophosphatemia compared with normophosphatemics (44% vs. 21%, P = 0.021; 59% vs. 33%, P = 0.021; and 43% vs. 13%, P = 0.004, respectively). Hypophosphatemic patients had higher maximum SOFA scores [10 (7-11) vs. 7.5 (5.75-10), P = 0.024]. Initial phosphate concentration correlated inversely with APACHE II score on admission (ρ = -0.304, P = 0.002) and SOFA score on the first ICU day (ρ = -0.269, P = 0.008). There was no difference in outcome between hypophosphatemic and normophosphatemic patients. In all five patients with severe hypophosphatemia (Pi < 0.32 mmol/l) the functional outcome was good.

CONCLUSION: Hypophosphatemia was common in this patient population. The outcome was similar between hypophosphatemic and normophosphatemic patients. Chronic hypertension, acute hydrocephalus, diffuse brain edema and higher SOFA scores were more common in patients with hypophosphatemia.