Passive leg raising performed before a spontaneous breathing trial predicts weaning-induced cardiac dysfunction
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Weaning-induced cardiac dysfunction is more likely to occur if the heart does not tolerate the changes in loading conditions induced by spontaneous breathing trial (SBT). We hypothesized that the presence of cardiac preload independence before an SBT is associated with weaning failure related to cardiac dysfunction.
We included 30 patients after a first failed 1-h T-tube SBT who had a transpulmonary thermodilution already in place. Preload independence [no increase in the pulse contour analysis-derived cardiac index ≥10 % during passive leg raising (PLR)] was assessed before the second SBT. Failure of the SBT related to cardiac dysfunction was defined by an increase in pulmonary artery occlusion pressure above 18 mmHg at the end of the SBT associated with clinical intolerance.
Fifty-seven SBTs were analyzed. The SBT failed in 46 cases. Overall, 31 failed SBTs were associated with weaning-induced cardiac dysfunction. During PLR, the cardiac index did not change in cases of failed SBTs with cardiac dysfunction, whereas it significantly increased in the other cases: 4 % (interquartile range, IQR 0–5) vs. 12 % (IQR 11–15), respectively. If PLR did not increase the cardiac index by more than 10 % before the SBT, the occurrence of SBT failure related to cardiac dysfunction was predicted with a sensitivity of 97 % [95 % confidence interval (CI) 83–100], specificity of 81 % (95 % CI 61–93) and area under the receiver-operating characteristic curve of 0.88 (95 % CI 0.78–0.98).
Preload independence assessed by a negative PLR test performed before an SBT predicts weaning failure related to cardiac dysfunction.
KeywordsMechanical ventilation Weaning Pulmonary edema Passive leg raising
Conflicts of interest
Jean-Louis Teboul and Xavier Monnet are members of the Medical Advisory Board of Pulsion Medical Systems. Martin Dres received honoraria for lectures from Pulsion Medical Systems. The other authors have no financial interest to disclose.
- 9.Dres M, Teboul J-L, Anguel N et al (2013) Preload independency as detected by passive leg raising is associated with weaning-induced pulmonary edema. In: Oral presentation at the ESCIM LIVES congress 2013Google Scholar
- 15.Moschietto S, Doyen D, Grech L et al (2012) Transthoracic echocardiography with Doppler tissue imaging predicts weaning failure from mechanical ventilation: evolution of the left ventricle relaxation rate during a spontaneous breathing trial is the key factor in weaning outcome. Crit Care 16:R81CrossRefPubMedCentralPubMedGoogle Scholar