Arterial oxygenation changes in valvular heart disease patients with cardiomegaly in different recumbent positions.
OBJECTIVE
We studied the effect of different recumbent positions (supine, left and right lateral decubitus), on arterial oxygenation in 42 valvular heart disease patients planned for cardiac surgery. All patients had cardiomegaly (cardiothoracic ratio > or = 0.5) in their chest X-rays. Their left ventricular end-diastolic diameter was also noted from the preoperative echocardiogram.


METHODS
Arterial blood gas analysis was performed in supine, left and right lateral positions after keeping the patient in a given position for 15 min. During this period all patients received 35% oxygen supplementation.


RESULTS
Arterial oxygen tension and haemoglobin saturation were significantly higher in the right lateral position (PaO2 = 120.6 +/- 29.5 mmHg, SaO2 = 98.1 +/- 1.4%) than in supine (PaO2 = 111.0 +/- 30.6 mmHg, SaO2 = 97.6 +/- 2.2%) and left lateral positions (PaO2 = 109.7 +/- 32.0 mmHg, SaO2 = 97.6 +/- 1.7%; mean +/- SD; P 0.05). The change in PaO2 and SaO2 with change of posture from left to right was significantly related to left ventricular end-diastolic diameter (r = 0.50 and r = 0.63, respectively; Pearson correlation). Repeated measures of analysis of variance with left ventricular end-diastolic diameter as a covariate showed a significant change in arterial PaO2 with posture (P = 0.011).


CONCLUSIONS
Right lateral posture improves arterial oxygenation in the valvular heart disease patient with an enlarged left ventricle. In the preoperative period, these patients may benefit from a right lateral posture when lying in bed.
Puri
G D
GD
Post Graduate Institute of Medical Education and Research (PGIMER), Department of Anaesthesia and Intensive Care and Department of Cardiothoracic and Vascular Surgery, Chandigarh, India. gdpuri007@hotmail.com
Dutta
A
A
Chinnan
N K
NK
Thingnam
S K S
SK
Sharma
S K
SK
Chari
P
P
D000293:Adolescent; D000328:Adult; D001784:Blood Gas Analysis; D006332:Cardiomegaly / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D005260:Female; D006349:Heart Valve Diseases / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010100:Oxygen / Q000097:blood*; D011187:Posture; D011446:Prospective Studies; D017534:Radial Artery / Q000502:physiology; D012121:Respiration, Artificial; D016276:Ventricular Function
D010100:Oxygen