Dataset Information

Noninvasive cardiac output monitoring in a porcine model using the inspired sinewave technique: a proof-of-concept study.

ABSTRACT:

Background

Cardiac output (Q?) monitoring can support the management of high-risk surgical patients, but the pulmonary artery catheterisation required by the current 'gold standard'-bolus thermodilution (Q?_T)-has the potential to cause life-threatening complications. We present a novel noninvasive and fully automated method that uses the inspired sinewave technique to continuously monitor cardiac output (Q?_IST).

Methods

Over successive breaths the inspired nitrous oxide (N₂O) concentration was forced to oscillate sinusoidally with a fixed mean (4%), amplitude (3%), and period (60 s). Q?_IST was determined in a single-compartment tidal ventilation lung model that used the resulting amplitude/phase of the expired N₂O sinewave. The agreement and trending ability of Q?_IST were compared with Q?_T during pharmacologically induced haemodynamic changes, before and after repeated lung lavages, in eight anaesthetised pigs.

Results

Before lung lavage, changes in Q?_IST and Q?_T from baseline had a mean bias of -0.52 L min^-1 (95% confidence interval [CI], -0.41 to -0.63). The concordance between Q?_IST and Q?_T was 92.5% as assessed by four-quadrant analysis, and polar plot analysis revealed a mean angular bias of 5.98° (95% CI, -24.4°-36.3°). After lung lavage, concordance was slightly reduced (89.4%), and the mean angular bias widened to 21.8° (-4.2°, 47.6°). Impaired trending ability correlated with shunt fraction (r=0.79, P<0.05).

Conclusions

The inspired sinewave technique provides continuous and noninvasive monitoring of cardiac output, with a 'marginal-good' trending ability compared with cardiac output based on thermodilution. However, the trending ability can be reduced with increasing shunt fraction, such as in acute lung injury.

SUBMITTER: Bruce RM

PROVIDER: S-EPMC6676057 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Publications

Noninvasive cardiac output monitoring in a porcine model using the inspired sinewave technique: a proof-of-concept study.

Bruce Richard M RM Crockett Douglas C DC Morgan Anna A Tran Minh Cong MC Formenti Federico F Phan Phi Anh PA Farmery Andrew D AD

British journal of anaesthesia 20190404 2

<h4>Background</h4>Cardiac output (Q˙) monitoring can support the management of high-risk surgical patients, but the pulmonary artery catheterisation required by the current 'gold standard'-bolus thermodilution (Q˙<sub>T</sub>)-has the potential to cause life-threatening complications. We present a novel noninvasive and fully automated method that uses the inspired sinewave technique to continuously monitor cardiac output (Q˙<sub>IST</sub>).<h4>Methods</h4>Over successive breaths the inspired ni ...[more]

PMID: 30954237

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Dataset Information

Noninvasive cardiac output monitoring in a porcine model using the inspired sinewave technique: a proof-of-concept study.

Background

Methods

Results

Conclusions

Publications

Noninvasive cardiac output monitoring in a porcine model using the inspired sinewave technique: a proof-of-concept study.

Similar Datasets

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