LAUSR

BACKGROUND Lactate dehydrogenase (LDH) is a non-specific inflammatory biomarker, and has been reported to be a useful predictor of community acquired pneumonia and mycoplasma pneumoniae pneumonia. However, the connection between LDH level and postoperative pneumonia (POP) in patients with aneurysmal subarachnoid hemorrhage (aSAH) is still unclear. OBJECTIVE To assess if it is feasible to predict occurrence of POP in aSAH patients using LDH level. METHODS 647 aSAH patients were enrolled into a prospective observational study and had admission serum LDH level taken. The relationship between LDH level and POP was analyzed. RESULTS POP occurred in 187 patients (28.90%) of this cohort. Patients with POP had significantly higher LDH level than those without (261.26±126.51 U/L vs. 189.00±69.20 U/L, P<0.001). Multivariate analysis showed that LDH level remained a significant independent factor associated with POP in aSAH patients, even after adjusting for possible confounding factors. Receiver operating characteristic curve analysis showed that LDH level had a sensitivity of 63.6% and a specificity of 71.3% for predicting POP based on the best threshold of 203.5U/L. There were additive interactions between elevated LDH level and the World Federation of Neurosurgical Societies (WFNS) grade, or mechanical ventilator (MV) use. When patients were classified by WFNS grade or MV use, regardless the WFNS grade (WFNS<3 or ≥3) or length of MV use (0-24 hours or ≥24 hours), the POP-free rate of patients having admission LDH>=250U/L was significantly worse than those with LDH<250 UL. CONCLUSIONS LDH might be a helpful predictor of POP occurrence in aSAH patients.