A comparison of the effects of lateral decubitus position and beach-chair position on airway pressure in arthroscopic shoulder surgery

The study was designed prospectively to evaluate two groups in fifty patients treated with shoulder arthroscopy, aged between 18-65 years and ASA I-II. Included patients were positioned according to the surgeon's choice. Patients positioned in lateral decubitus were considered as group L and beach chair positioned group was considered as group B. Induction anesthesia was performed with 1 µg/kg fentanyl, 1 mg/kg lidocaine, 2-3 mg/kg propofol in both group and then 0.6 mg/kg rocuronium was administered for neuromuscular blockade. Anesthesia maintenance was achieved with %50 oxygen, %50 nitrogen protoxide, %2-3 sevoflurane air mix in all patients. Heart rate, oxygen saturation, mean arterial pressure, BIS values, EtCO2, iPEEP, PAW, PVI, PI, body temperature were recorded before induction, after intubation at 5th, 15th, 30th, 45th, 60th, 75th, 90th, 105th, 120th, 135th minutes and after extubation. Neck, shoulder and chest circumference of the patients were measured preoperatively and postoperatively. Following extubation and in post anesthesia care unit, patients who achieved a modified Aldrete score >9 were evaluated whether they had dyspnea, chest pain, hoarseness, tachypnea, cyanosis, and desaturation. There was no difference between the groups regarding age, ASA, BMI, operation duration and totally replaced fluid. The mean total irrigation fluid volume used for patients in lateral decubitus position was higher than the other group. There was no significant difference in PAW measurements between the groups. Preoperative and postoperative measured mean neck circumferences were significantly higher in the L group. No significant difference was found in preoperative and postoperative chest and shoulder measurements between the groups. In conclusion, due to no difference of airway pressure increase between lateral decubitus and beach chair positions, both position can be applied safely. It is also concluded that the use of higher irrigation fluid can lead increased measurements in neck circumferences. Key Words: Shoulder Arthroscopy, Airway Pressure, İrrigation Fluid, Lateral Decubitus-Beach Chair Position.