The effect of incremental positive end-expiratory pressure on right ventricular hemodynamics and ejection fraction.
The effects of incremental positive end-expiratory pressure (PEEP) on right ventricular (RV) function were evaluated in 36 (n = 36) ventilated patients. Positive end-expiratory pressure was increased from 0 (baseline) to 20 cm H2O in 5-cm H2O increments and RV hemodynamics and thermally derived right ventricular ejection fraction (RVEF), right ventricular end-diastolic volume index (RVEDVI), and right ventricular end-systolic volume index (RVESVI) were computed. Right ventricular contractility was determined from the analysis of RV systolic pressure-volume relations. Right ventricular ejection fraction declined from 42 +/- 8% at baseline to 30 +/- 9% at 20 cm H2O PEEP. Right ventricular end-diastolic volume index declined between 0 and 5 cm H2O PEEP (103 +/- 42 to 92 +/- 34 ml.m-2) and then increased to 113 +/- 40 at 20 cm H2O PEEP. Right ventricular end-systolic volume index increased from 60 +/- 31 ml.m-2 at baseline to 79 +/- 34 ml.m-2 at 20 cm H2O PEEP. The slope (E) of the relation of RV peak systolic pressure to RV end-systolic volume index decreased from 0.26 mm Hg.m2.ml-1 between PEEP of 0-15 cm H2O to 0.05 mm Hg.m2.m-1 at PEEP greater than 15 cm H2O. It is concluded that low levels of PEEP have a predominant preload reducing effect on the RV. Above 15 cm H2O PEEP, RV volumes increase and E decreases, consistent with increased RV afterload and a decline in RV contractility.
Biondi
J W
JW
Department of Anesthesiology, Yale University School of Medicine, New Haven, Connecticut 06510.
Schulman
D S
DS
Soufer
R
R
Matthay
R A
RA
Hines
R L
RL
Kay
H R
HR
Barash
P G
PG
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002302:Cardiac Output; D002306:Cardiac Volume; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000628:therapy; D007385:Intermittent Positive-Pressure Ventilation; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011175:Positive-Pressure Respiration; D011183:Postoperative Complications / Q000628:therapy; D013318:Stroke Volume