title: End-tidal carbon dioxide concentration can estimate the appropriate timing for weaning off from extracorporeal membrane oxygenation for refractory circulatory failure.
abstract: Although extracorporeal membrane oxygenation (ECMO) is widely used as temporary circulation support, there are no reports of direct parameters indicating cardiac recovery to determine the timing of weaning off. Twenty-five patients supported by ECMO due to hemodynamic deterioration were divided into 2 groups according to their outcome: weaned ECMO (W: n = 18) or not (NW: n = 7). In the W group, we examined the differences in parameters between the 2 time points, ECMO introduction, and the reduction in ECMO flow to 40% of the initial setting known as the conventional recovery point (C-point). Significant differences were observed in systolic pulmonary artery pressure, the cardiac index measured by the thermodilution method, C-reactive protein, lactate, base excess, and the end-tidal CO(2) concentration (ETCO(2)). Next, by closely examining these 6 parameters measured every 12 hours, we found that only ETCO(2) had always changed steeply, like a 'flexion point' (E-point), in all W cases, but not in NW. The E-point was defined as an initial increase in ETCO(2) of >or= 5 mmHg over the preceding 12 hours with a continued rise over the next 12 hours. E-points appeared as much as 95 +/- 60 hours earlier than C-points and also preceded weaning off of ECMO. ETCO(2) can be a useful continuous parameter for predicting the adequate timing of weaning off of ECMO for circulatory failure at the bedside.
authors.affiliation: Department of Cardio-Angiology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Naruke
authors.forename: Takayuki
authors.initials: T
authors.lastname: Inomata
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imai
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Yanagisawa
authors.forename: Emi
authors.initials: E
authors.lastname: Maekawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Mizutani
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Osaka
authors.forename: Hisahito
authors.initials: H
authors.lastname: Shinagawa
authors.forename: Toshimi
authors.initials: T
authors.lastname: Koitabashi
authors.forename: Mototsugu
authors.initials: M
authors.lastname: Nishii
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takeuchi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Takehana
authors.forename: Naoyoshi
authors.initials: N
authors.lastname: Aoyama
authors.forename: Tohru
authors.initials: T
authors.lastname: Izumi
mesh_terms: D000328:Adult; D000368:Aged; D019296:Capnography; D002245:Carbon Dioxide / Q000378:metabolism*; D015331:Cohort Studies; D015199:Extracorporeal Membrane Oxygenation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D020127:Recovery of Function; D012189:Retrospective Studies; D012769:Shock / Q000378:metabolism* / Q000401:mortality / Q000628:therapy*; D013990:Tidal Volume / Q000502:physiology; D016896:Treatment Outcome; D015300:Ventilator Weaning
chemical_list: D002245:Carbon Dioxide