The fraction of nitrous oxide in oxygen for facilitating lung collapse during one-lung ventilation with double lumen tube

Abstract

Background: The ideal fraction of nitrous oxide (N 2 O) in oxygen (O 2) for rapid lung collapse remains unclear. Accordingly, this prospective trial aimed to determine the 50% effective concentration (EC 50) and 95% effective concentration (EC 95) of N 2 O in O 2 for rapid lung collapse. Methods: This study included 38 consecutive patients undergoing video-assisted thoracoscopic surgery (VATS). The lung collapse score (LCS) of each patient during one-lung ventilation was evaluated by the same surgeon. The first patient received 30% N 2 O in O 2 , and the subsequent N 2 O fraction in O 2 was determined by the LCS of the previous patient using the Dixon up-and-down method. The testing interval was set at 10%, and the lowest concentration was 10% (10, 20, 30, 40%, or 50%). The EC 50 and EC 95 of N 2 O in O 2 for rapid lung collapse were analyzed using a probit test. Results: According to the up-and-down method, the N 2 O fraction in O 2 at which all patients exhibited successful lung collapse was 50%. The EC 50 and EC 95 of N 2 O in O 2 for rapid lung collapse were 27.7% (95% confidence interval 19.9-35.7%) and 48.7% (95% confidence interval 39.0-96.3%), respectively. Conclusions: In patients undergoing VATS, the EC 50 and EC 95 of N 2 O in O 2 for rapid lung collapse were 27.7 and 48.7%, respectively.

Combination of nitrous oxide and the modified inflation‐deflation method for identifying the intersegmental plane in segmentectomy: A randomized controlled trial

“…Several lines of evidence have reported that inspired mixture gas containing N 2 O could significantly accelerate the rate of gas absorption, thereby rapidly resulting in lung collapse. [12][13][14] In this regard, we performed a prospective randomized trial to investigate the efficacy and safety of the combined modified inflation-deflation method with N 2 O mixture inspired gas on the appearance time of the ISP (T ISP ) during segmentectomy.…”

The anesthesia management of totally thoracoscopic cardiac surgery: A single-center retrospective study

“… pre-operative respiratory muscle endurance training (RMET): Patients undergoing cardiac surgery are at risk of pulmonary complications, which leads to increased intra- and post-operative morbidity and mortality. Because of CPB [ 36 ] and OLV [ 37 ], patients who undergo TTCS are more likely to develop perioperative pulmonary complications. Currently, studies have shown that pre-operative respiratory training can reduce pulmonary complications and shorten the LOS for POD [ 14 , 16 , 17 ].…”

Prediction of Left Double-Lumen Tube Size by Measurement of Cricoid Cartilage Transverse Diameter by Ultrasound and CT Multi-Planar Reconstruction

“…Objective criteria were injected air into the cuff. When the pressure inside the LDLT was 25 mmHg, it was stopped and connected to the anesthesia machine, when the peak pressure of positive pressure ventilation airway was below 30 cm H 2 O, the air leakage phenomenon was adjusted ( 13 ).…”

“…There was obvious resistance when the LDLT entered the trachea or bronchus, or the LDLT tip could not enter the bronchus after being guided by a fiberoptic bronchoscope. Good pulmonary isolation could be achieved by injecting <1 ml of air into the bronchial cuff and <2 ml of air into the main tracheal cuff ( 13 ).…”

“…When the cuff pressure was adjusted to the standard value with the manometer after the LDLT was inserted successfully, the two lungs of the patients with airway leakage who needed injection of more than 3 or 6 ml of air into the two cuff could be satisfactorily isolated, and the LDLT size was considered to be too small ( 13 ).…”