Catheterization of the subclavian vein and the risk of pneumothorax. Mechanical ventilation increases the risk of pneumothorax during infraclavicular landmark-guided subclavian vein puncture: a prospective randomized study

BackgroundInfraclavicular subclavian vein (SCV) catheterization is astandard procedure in anesthesia and intensive care. There is alack of evidence on how mechanical ventilation during venipuncture of the SCV influences pneumothorax rates.ObjectivePrimary hypothesis: non-inferiority of continuing vs. discontinuing mechanical ventilation during infraclavicular puncture of the SCV with respect to the pneumothorax rate.Material and methodsThis prospective, randomized and single-blinded study was approved by the local ethics committee. Atotal of 1021 eligible patients who underwent cranial neurosurgery in 2 different university hospitals were assessed between August 2014 and October 2017. Patients were randomly assigned to two groups directly before induction of anesthesia. Intervention groups for venipuncture of the SCV were mechanical ventilation: tidal volume 7ml/kg ideal body weight, positive end expiratory pressure (PEEP) ideal body weight/10, n=535, or apnea: manual/spontaneous, APL valve 0mbar, n=486. Patients and the physicians who assessed pneumothorax rates were blinded to the intervention group. Venipuncture was carried out by both inexperienced and experienced physicians.ResultsThe pneumothorax rate was significantly higher in the mechanical ventilation group (2.2% vs. 0.4%; p=0.012) with an odds ratio (OR) of 5.63 (95% confidence interval, CI: 1.17-27.2; p=0.031). Alower body mass index (BMI) was associated with ahigher pneumothorax rate, OR 0.89 (95% CI: 0.70-0.96; p=0.013).ConclusionIn this study landmark-guided infraclavicular SCV catheterization was associated with asignificantly higher rate of pneumothorax when venipuncture was performed during mechanical ventilation and not in apnea. If ashort phase of apnea is justifiable in the patient, mechanical ventilation should be discontinued during the venipuncture procedure.