Research in the zero point position of central venous pressure under 45° or 90° lateral position

Objective To discuss the zero point position of central venous pressure(CVP) by determining the difference of CVP under 45°,90°lateral position and supine position. Methods The CVP of 50 cases performed elective surgery undergoing tracheal intubation anesthesia were measured of lateral position and supine position at the same time,the position of the sensor in the chest wall was marked when the CVP values was the same in the two positions by means of moving the sensors,while changes of BP,HR,SpO2,RR were recorded. Results The CVP under right 45°,90° and left 90° lateral position were statistically significant than that under supine position,the CVP under left 45° lateral position was not significanfly different from that under supine position.The zero point under right 45°,90°and left 45°,90°lateral position situated at the left side of the right anterior axillary line (0.8 ± 0.4)cm,the upper side of the right sterna border line (0.8 ± 0.2)cm,the right side of the left anterior axillary line (0.3 ± 0.2)cm,the lower side of the left sternal border line (2.2 ± 0.3)cm. Conclusions The zero point position determined by monitoring the changes of CVP under lateral position can not only comfortably measure CVP but also avoid discomfort and complications in patients by forced supine position. Key words: Lateral position; Central venous pressure; Zero point position