Lung Ventilation During Cardiopulmonary Resuscitation

The authors to measure passive tidal volumes generated during external chest compressions in order to determine whether chest compressions alone without any mechanical ventilatory support in cardiopulmonary resuscitation can provide adequate ventilation. The authors will study 25 volunteers who meet the following inclusion criteria: age 18-55 years, ASA I-II, candidates for surgical operation, who will receive general anesthesia. Patients who will be operated in the chest, who present musculoskeletal diseases, cardiopulmonary or vascular acute or chronic diseases, who had history of pneumothorax, of thromboembolism, osteoporosis, menopause, history of current rib or sternal or clavicle fractures, will be excluded. All eligible patients will enter the study and will receive general anesthesia and intubation according to treating doctors' decision.

Patients will be ventilated mechanically for 5 minutes to establish stable conditions. A pneumotachograph will be then connected to the ventilatory circuit so that respiratory efforts (volume, airway pressure and flow) can be continuously monitored at real time.

An esophageal catheter will be then inserted to monitor esophageal pressures and to provide data for lung mechanics calculation. Following the above procedures and before any surgical procedure, chest compressions will be performed to the patient by a senior anesthesiologist according to ERC guidelines of 2010 for 30 seconds.

Following chest compressions, patients will be evaluated for possible complications and after the establishment of stable conditions surgical procedures will follow. After the end of the surgical operation clinical and chest ultrasound evaluation will be performed.

Written inform consent will be obtained by all patients before procedures.