Objectives: To determine incidence of hypophosphatemia (HP) among severe sepsis/septic shock patients admitted to ICU and its impact on morbidity and mortality rates and to evaluate the impact of phosphorous supplemental therapy (PST) on such outcomes.
Patients & Methods: 65 septic shock and 252 severe sepsis patients were categorized according to at-admission inorganic phosphate (Pi) level (T0)into normophosphatemia (NP; n=238) and mild, moderate and severe HP (n= 24, 38 and 17 patients, respectively). All patients were evaluated using sequential organ failure assessment (SOFA) and acute physiology and chronic health evaluation II score (APACHE II) and gave blood sample for T0 ELISA estimation of serum Pi, human C-reactive protein (CRP) and L-lactate. Sepsis was managed according to Surviving Sepsis Campaign guidelines and dose of PST was calculated and administered on 4-hourly divided doses. Serum Pi level was re-estimated immediate and 24-hr after full dose administration. Outcomes included the 28-day ICU morbidity and mortality rates and their relation to HP severity and PST administration.
Results: PST administration increased serum Pi levels by 73 (±44.5)% of T0 level and after 24-hr serum Pi level was re-dropped in 24 patients, but still higher than T0 level and was within normal range in 55 patients. Morbidity and mortality rates were non-significantly higher among HP than NP patients and were negatively correlated with the percentage of change in serum Pi estimated 24-hr after PST. Regression analysis defined low at admission serum Pi and high SOFA score as most significant predictors for development of morbidities and mortalities during ICU stay.
Conclusion: Sepsis induces decreased levels of serum Pi and the extent of decrease increases with sepsis severity. Early detection of HP and institution of PST is mandatory to reduce morbidity and mortality rates and this reduction correlates with Pi deficit improvement.