Chest
clinical investigationsCardiac Augmentation By Phasic High Intrathoracic Pressure Support In Man
Section snippets
MATERIALS AND METHODS
Seven patients in the medical intensive care unit of Johns Hopkins University Hospital, Baltimore, served as our subjects for this study. All subjects were gravely ill with severe shock either due to sepsis (four) or myocardial infarction (three). All were being treated aggressively with conventional fluid resuscitation and vasoactive drugs. Profiles of the patients are shown in Table 1. Criteria for entrance into this study included the following: (1) severe hypotension secondary to depressed
RESULTS
The hemodynamic data for all seven subjects are summarized in Table 2. The PHIPS was associated with an increase in mean Pes of 6.6 ± 1.1 mm Hg (mean±SE) over the control states (p<0.001). There was no significant difference between the two control states in any of the hemodynamic variables, although the trend over time was to a lower cardiac output, mean arterial pressure, and Pes. This is consistent with the progressive hemodynamic deterioration that the subjects demonstrated both before and
DISCUSSION
Left ventricular function can be described by the relationship between cardiac output and left ventricular filling pressure.9 Our study demonstrates that in the setting of severe left ventricular dysfunction (ie, with an expanded intravascular blood volume), increasing intrathoracic pressure improves left ventricular performance. These results are in agreement with recent reports.4,10,11 Buda and co-workers4 found that with sustained increases in intrathoracic pressure, left ventricular
ACKNOWLEDGMENTS
We thank Ms. Nancy Gordon for secretarial assistance in preparing this manuscript.
REFERENCES (16)
- et al.
Multiple gated cardiac blood pool imaging for left ventricular ejection fraction: validation of the technique and assessment of variability
Am J Cardiol
(1979) Haemodynamic effects of pulmonary ventilation
Br J Anaesth
(1975)- et al.
Effects of spontaneous respiration on canine left ventricular function
Circ Res
(1979) - et al.
Effect of intrathoracic pressure on left ventricular performance
N Engl J Med
(1979) - et al.
Cough-induced cardiac compression
JAMA
(1976) - et al.
Augmentation of cardiac function by elevation of intrathoracic pressure
J Appl Physiol
(1983) - et al.
Improved technique for estimating pleural pressure from esophageal balloons
J Appl Physiol
(1974) Myocardial contractility as described by ventricular function curves: observations on Starlings law of the heart
Physiol Rev
(1955)
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Supported by National Research Service Award IF32HL-06238-01.
Manuscript received November 20; revision accepted April 28.