Comparative efficacy of Supraclavicular versus Infraclavicular approach of Subclavian vein cannulation under ultrasound guidance: A randomized clinical trial

Patients who are undergoing elective and emergency surgeries requiring central venous catheterization under general anaesthesia will be scanned for eligibility criteria, those fulfilling eligibility criteria, after explaining the procedure and purpose of the study ,written informed consent will be obtained and will be randomized into 2 groups by using computer generated random number technique.

Upon arrival in the operating room, standard monitoring including electrocardiogram (ECG), Non-invasive arterial blood pressure (NIBP), heart rate (HR) and pulse oximetry (SpO2) will be applied and adequate peripheral venous access will be established. General Anesthesia will be induced and after administration of muscle relaxant and patient will be intubated and  mechanically ventilated. Anesthesia will be maintained with inhalational agents. All procedures will be performed on the right subclavian vein by a qualified anesthesiologist with an experience of at least 25 procedures using both the approaches for ultrasound guided subclavian vein catheterization. A post graduate junior resident will be recorded the puncture time, number of attempts, catheter insertion time and incidence complications. All times will be measured in seconds.Ultrasound with linear probe will be used for this study.

In supraclavicular long axis approach, the internal jugular vein will be traced down the neck under ultrasound guidance and after reaching the internal jugular vein-subclavian vein junction, the probe will be turned laterally to obtain the longitudinal images of the subclavian vein.

In infraclavicular long axis approach, ultrasound probe will be positioned almost parallel moving away from the clavicle and the entry point of the needle will be in plane with the probe. With this approach, only the subclavian visible on the  screen.

The needle will be hold at 45 degree angle, will be oriented in plane with transducer and the skin will be punctured at the base of the transducer. The vein alignment will be maintained during the procedure and the entire length of the needle will be visible during the progression through the tissues. Entry of the tip into the vein will be confirmed by blood aspiration.