Evaluation of the hemodynamic and respiratory effects of inverse ratio ventilation with a right ventricular ejection fraction catheter.
Pc-IRV has been shown to have respiratory advantages, compared with CPPV. However, the hemodynamic effects of this ventilation mode have not yet been fully elucidated. We used a REF catheter to monitor the hemodynamic changes in the RV. Fifteen ARDS patients were included in the study. The respiratory data showed a 35 percent decrease of PIP and a 32 percent decrease of VTi and VTe with Pc-IRV 4:1 compared with CPPV. Hemodynamic parameters showed a significant incrase in CI (17 percent) in Pc-IRV 4:1, without change in REF. Observing in retrospect the pressure-volume relationship of the RV, we could differentiate a preload (group 1) and an afterload dependent group of patients (group 2), CI was significantly different in the two groups as it rose only in the preload-dependent patients. RVEDVI showed a significant change in group 1, whereas this was absent in the second group. REF was maintained in switching ventilation from CPPV to Pc-IRV with increasing I:E ratio. Pc-IRV appears to be a good alternative ventilatory mode in comparison with CPPV in a selected group of patients with preload dependency (responders); in these patients with respiratory insufficiency, close hemodynamic monitoring is required to optimize ventilation, especially in relation to the hemodynamic effects.
Poelaert
J I
JI
Department of Intensive Care, University Hospital, Chent, Belgium.
Vogelaers
D P
DP
Colardyn
F A
FA
D000293:Adolescent; D000328:Adult; D002407:Catheterization, Swan-Ganz; D005069:Evaluation Studies as Topic; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000503:physiopathology / Q000628:therapy; D015656:Respiratory Mechanics; D013318:Stroke Volume