Lung deflation while placing a subclavian vein catheter: Our experience in minimizing the risk of pneumothorax

PURPOSE: Lung deflation may reduce the risk of pneumothorax based on the assumption that the distance between the subclavian vein and the lung pleura would increase as well as the diameter of the vein. We aim to provide evidence to support the suggested desideratum of deflation in adults. METHODS: A prospective database was created that included patients who underwent subclavian vein catheterization for monitoring and therapeutic reasons from January 2014 to January 2020. Measurements using ultrasonography of the diameter of the subclavian vein were taken while the patient’s breathing was controlled by a ventilator and then repeated after disconnecting the mechanical ventilation and opening the pressure relief valve. RESULTS: A total of 123 patients were enrolled, with an average age of 41.9 years. The subclavian vein diameter was measured during controlled breathing with a mean average of 8.1 ± 0.6mm in males and 7.1 ± 0.5mm in females. The average increase after lung deflation with the pressure relief valve closed was 8.0± 5.1mm in males and 13.9 ± 5.4mm in females. An increase was noticed after opening a pressure valve, and the means were 5.5 ± 2.8mm in males and 5.1 ± 3.3mm in females. The catheter malposition rate was 0.8% CONCLUSION: The benefit of interrupting mechanical ventilation and lung deflation lies within possibly avoiding pneumothorax as a complication of subclavian vein catheterization. These findings support the need for evidence regarding the curtailment of pneumothorax incidence in spontaneously breathing patients and the suggested increase in first-time punctures and success rates.