Effect of the 30 degree lateral recumbent position on pulmonary artery and pulmonary artery wedge pressures in critically ill adult cardiac surgery patients.
BACKGROUND
Despite demonstrated benefits of lateral positioning, critically ill patients may require prolonged supine positioning to obtain reproducible hemodynamic measurements.


OBJECTIVE
TO determine the effect of 30 degree right and left lateral positions on pulmonary artery and pulmonary artery wedge pressures after cardiac surgery in critically ill adult patients.


METHODS
An experimental repeated-measures design was used to study 35 patients with stable hemodynamics after cardiac surgery. Subjects were randomly assigned to 1 of 2 position sequences. Pulmonary artery and pulmonary artery wedge pressures were measured in each position.


RESULTS
Measurements obtained from patients in the 30 degree left lateral position differed significantly (all Ps < .05) from measurements obtained from patients in the supine position for pulmonary artery systolic, end-diastolic, and mean pressures. Pulmonary artery wedge pressures did not differ significantly; however, data were available from only 17 subjects. The largest mean difference in pressures between the 2 positions was 2.0 +/- 2.1 mm Hg for pulmonary artery systolic pressures, whereas maximum differences for end-diastolic and pulmonary artery wedge pressures were 1.4 +/- 2.7 mm Hg and 1.6 +/- 2.4 mm Hg, respectively. Clinically significant position-related changes in pressure occurred in 12 (2.1%) of 581 pressure pairs. Clinically significant changes occurred in end-diastolic pressure in 2 subjects and in pulmonary artery wedge pressure in 1 subject.


CONCLUSIONS
In patients with stable hemodynamics during the first 12 to 24 hours after cardiac surgery, measurements of pulmonary artery and pulmonary artery wedge pressures obtained in the 30 degree lateral and supine positions are clinically interchangeable.
Bridges
E J
EJ
Nursing Research, 59th Medical Wing, Lackland, AFB, Tex, USA.
Woods
S L
SL
Brengelmann
G L
GL
Mitchell
P
P
Laurent-Bopp
D
D
D000328:Adult; D006348:Cardiac Surgical Procedures / Q000451:nursing; D015400:Clinical Nursing Research; D003422:Critical Care / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods* / Q000451:nursing; D011182:Postoperative Care / Q000379:methods / Q000451:nursing; D011187:Posture / Q000502:physiology*; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D013318:Stroke Volume / Q000502:physiology; D016683:Supine Position / Q000502:physiology; D013997:Time Factors