The prognostic value of peak arterial lactate levels within 72 h of lung transplantation in identifying patient outcome

BACKGROUND: Lactic acidosis is often seen in lung transplantation (LTx). Postoperative lactate is frequently associated with poor outcome in postoperative and critically ill patients. Our aim was to evaluate the predictive value of postoperative peak lactate levels within 72 h of LTx for 30-day and late mortality. METHODS: We evaluated patients who underwent LTx from January 2015 to September 2017. All admitted patients were classified according to the peak lactate level (PL) within 72 h of surgery: PL <5 mmol/L (Group 1); PL =5–10 mmol/L (Group 2), and PL >10 mmol/L (Group 3). We performed logistic regression analysis and used Cox regression models to identify the peak lactate level as a predictive factor for 30-day and late mortality, respectively. RESULTS: Of 255 eligible patients, mean age 55.61±12.16, mean lactate 4.99±2.93 and 80% male, and 40% had hyperlactatemia (PL >5 mmol/L) after LTx. The 30-day mortality rate was 17.9%, 28.9% and 68.8% in the three groups, respectively (P<0.05). Multivariate regression analyses revealed postoperative PL as a notable predictor of 30-day mortality [odds ratio =2.62 (1.42–4.84), P=0.002] as well as for late mortality [hazard ratio =2.70 (1.13–6.42), P=0.025]. CONCLUSIONS: The postoperative peak lactate level within 72 h of surgery was an independent predictor for 30-day and late mortality in LTx patients.