Related Experiment Videos
Acute cardiovascular response to passive leg raising
D H Wong1, K K Tremper, J Zaccari
1Department of Anesthesiology, University of California, Irvine Medical Center, Orange.
Critical Care Medicine
|February 1, 1988
Summary
Passive leg raising (PLR) minimally increased cardiac index and transcutaneous oxygen tension, while slightly decreasing oxygen saturation in patients. Most patients did not show a significant hemodynamic response to PLR.
Area of Science:
- Cardiovascular Physiology
- Hemodynamics
- Critical Care Medicine
Background:
- Passive leg raising (PLR) is a maneuver used to assess fluid responsiveness.
- Understanding the hemodynamic effects of PLR is crucial for clinical decision-making.
Purpose of the Study:
- To evaluate the hemodynamic and oxygenation responses to passive leg raising (PLR) in a patient cohort.
- To determine the percentage of patients exhibiting a significant increase in cardiac index after PLR.
Main Methods:
- Measurements of cardiac output (thoracic bioimpedance), heart rate, blood pressure (BP), oxygen saturation, and transcutaneous oxygen tension were taken.
- Data were collected at 1-minute intervals before and after the PLR maneuver in 45 patients.
Main Results:
- Mean cardiac index showed a small but significant increase (0.09 L/min/m2, p < .001).
- Mean transcutaneous oxygen tension increased (1.6 torr, p < .01), while mean oxygen saturation decreased slightly (0.5%, p < .01).
- Only 16% of patients experienced a >10% increase in cardiac index; no significant changes in heart rate or systolic BP were observed.
Conclusions:
- Passive leg raising elicits a modest increase in cardiac index and oxygen tension, with a slight decrease in oxygen saturation.
- The majority of patients in this study did not demonstrate a substantial increase in cardiac index following PLR, suggesting limited predictive value for fluid responsiveness in this group.