In our study, we aimed to detect atelectasis developing in patients undergoing surgery under general anesthesia using transthoracic lung ultrasonography and to investigate the effect of ventilation methods used during recovery from anesthesia on the formation of postoperative atelectasis.

Postoperative atelectasis is one of the most common pulmonary complications seen in surgical patients. Postoperative pulmonary complications and possible respiratory side effects have long been associated with anesthesia. Pulmonary complications are an important cause of morbidity and mortality in the postoperative period. The incidence of postoperative pulmonary complications due to long-term anesthesia varies between 5% and 80%, depending on the patient population, the surgery performed, and the criteria used to define the complication. It is known that the recovery period makes a significant contribution to the total amount of postoperative atelectasis. Spontaneously breathing patients are under the influence of anesthetic agents and neuromuscular blockers and cannot regain their functional residual capacity. For this reason, it is emphasized that atelectasis may develop in the postoperative period in cases whose anesthesia application is terminated by applying a spontaneous breathing period. Pressure support ventilation (PSV) is widely used for ventilator weaning in the intensive care unit (ICU) and has recently been available on anesthesia machines.

It is expected that the use of lung ultrasonography in operating rooms can reduce the complications that may develop in the postoperative period with evidence-based detection and early postoperative detection of atelectasis in the early postoperative period.

In this study, it was aimed to compare the effect of pre-extubation ventilation mode applied by anesthesia practitioners with ultrasound in the postoperative period on the frequency of atelectasis in adult patients who underwent surgery and whose lungs were evaluated as normal by ultrasound in the preoperative observation room. Modified LUS scores were used as lung ultrasonography evaluation criteria in the study.

Inclusion Criteria:

• Patients undergoing general anesthesia with supine position
• Endotracheal intubations and mechanical ventilation during general anesthesia
• Operation time is more than 2 hours

Exclusion Criteria:

• Patients who will undergo surgical intervention under emergency conditions
• Pregnancy
• Upper respiratory tract disease in the last 3 weeks
• Previous lung surgery
• Advanced cardiac and/or pleural lung disease and chest wall deformity, and primary or metastatic lung cancer

The patients 18 years of age or older and American Society of Anesthesiologists (ASA) physical status I and III who were scheduled for general anesthesia were included in this prospective observational study.