Abstract
Objective The relationship of a preoperative Prognostic Nutritional Index (PNI) with perioperative
adverse events (PAEs) other than delirium has never been described in patients undergoing
spinal surgery. We aimed to evaluate the impact of admission PNI on the outcome of
patients undergoing spinal surgery.
Methods Medical records of 408 consecutive patients 50 years or older undergoing spinal surgery
were reviewed. Patients' information including demographic data, routine preoperative
laboratory tests, and PNI were collected to assess the association between these factors
and PAEs. The PNI was calculated from this formula: 10 × serum albumin (g/dL) + 0.005 × total
lymphocyte count/mm3. Receiver operating characteristic curve analysis was performed to determine the
cutoff value of the PNI.
Results PAEs occurred in 61 (14.9%) of the patients. Older patients and those with more comorbid
conditions such as atrial fibrillation, chronic renal failure, history of malignancy,
and diabetes mellitus tended to have a higher rate of PAEs. Patients with PAEs had
higher C-reactive protein (4.4 ± 5.4 vs 2.2 ± 3.0 mg/dL; p < 0.001) but had lower hemoglobin levels (12.2 ± 1.57 vs 13.1 ± 1.84 g/dL; p < 0.001) on admission. Patients who had PAEs had a significantly lower preoperative
PNI (46.1 ± 4.4 vs 51.9 ± 5.8; p < 0.001) compared with patients without a PAE. Multivariate analysis showed that
age (odds ratio [OR]: 1.23; 95% confidence interval [CI] 0.76–1.35; p < 0.04), PNI < 47.7 (OR: 2.51; 95% CI, 1.188–5.477; p = 0.008) and the presence of diabetes (OR: 3.23; 95% CI, 11.326–7.474; p = 0.004) were significant and independent predictors of PAEs.
Conclusion This study is the first to demonstrate that a lower preoperative PNI is associated
with PAEs in patients undergoing spinal surgery.
Keywords
Prognostic Nutritional Index - spinal surgery - perioperative adverse event
