Dataset Information

Estimated Pao₂: A Continuous and Noninvasive Method to Estimate Pao₂ and Oxygenation Index.

ABSTRACT: Pao₂ is the gold standard to assess acute hypoxic respiratory failure, but it is only routinely available by intermittent spot checks, precluding any automatic continuous analysis for bedside tools.

Objective

To validate a continuous and noninvasive method to estimate hypoxemia severity for all Spo₂ values.

Derivation cohort

All patients who had an arterial blood gas and simultaneous continuous noninvasive monitoring from 2011 to 2019 at Boston Children's Hospital (Boston, MA) PICU.

Validation cohort

External cohort at Sainte-Justine Hospital PICU (Montreal, QC, Canada) from 2017 to 2020.

Prediction model

We estimated the Pao₂ using three kinds of neural networks and an empirically optimized mathematical model derived from known physiologic equations.

Results

We included 52,879 Pao₂ (3,252 patients) in the derivation dataset and 12,047 Pao₂ (926 patients) in the validation dataset. The mean function on the last minute before the arterial blood gas had the lowest bias (bias -0.1% validation cohort). A difference greater than or equal to 3% between pulse rate and electrical heart rate decreased the intraclass correlation coefficients (0.75 vs 0.44; p < 0.001) implying measurement noise. Our estimated Pao₂ equation had the highest intraclass correlation coefficient (0.38; 95% CI, 0.36-0.39; validation cohort) and outperformed neural networks and existing equations. Using the estimated Pao₂ to estimate the oxygenation index showed a significantly better hypoxemia classification (kappa) than oxygenation saturation index for both Spo₂ less than or equal to 97% (0.79 vs 0.60; p < 0.001) and Spo₂ greater than 97% (0.58 vs 0.52; p < 0.001).

Conclusion

The estimated Pao₂ using pulse rate and electrical heart rate Spo₂ validation allows a continuous and noninvasive estimation of the oxygenation index that is valid for Spo₂ less than or equal to 97% and for Spo₂ greater than 97%. Display of continuous analysis of estimated Pao₂ and estimated oxygenation index may provide decision support to assist with hypoxemia diagnosis and oxygen titration in critically ill patients.

SUBMITTER: Sauthier M

PROVIDER: S-EPMC8480940 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:Background & aimsSignificantly worse survival has been reported in patients with hepatopulmonary syndrome (HPS) and partial pressure of arterial oxygen (PaO2) <45 mmHg undergoing liver transplantation. Long-term pre- and post-transplant outcomes based on degree of hypoxaemia were re-examined.MethodsA retrospective analysis of 1,152 HPS candidates listed with an approved HPS model for end-stage liver disease (MELD) exception was performed. A Fine and Gray competing risks model was utilised to evaluate pre-transplant outcomes for PaO2 thresholds of <45, 45 to <60, and ≥60 mmHg. Post-transplant survival was analysed using the Kaplan-Meier method.ResultsPatients with a PaO2 <45 mmHg were significantly more likely to undergo transplantation (hazard ratio [HR] 1.51; 95% CI 1.12-2.03), whereas patients with higher MELD scores had lower hazard of transplant (HR 0.80, 95% CI 0.67-0.95, p = 0.011) and higher hazard of pre-transplant death (HR 2.29, 95% CI 1.55-3.37, p <0.001). Post-transplantation, patients with a PaO2 <45 mmHg had lower survival (p = 0.04) compared with patients with a PaO2 ≥45 to <50 mmHg, with survival curves significantly different at 2.6 years (75% survival compared with 86%) and median survival of 11.5 and 14.1 years, respectively. Cardiac arrest was a more likely (p = 0.025) cause of death for these patients. Cardiac arrest incidence in patients who died with a PaO2 >50 mmHg was 6.2%.ConclusionsPatients with a PaO2 <45 mmHg had a significantly higher rate of transplantation, and higher calculated MELD scores were associated with significantly higher pre-transplant mortality. Although post-transplant survival was lower in patients with a PaO2 <45 mmHg, the median survival was 11.5 years, and survival curves only became significantly different at 2.6 years. This suggests that patients with HPS do benefit from transplantation up to 2-3 years post-transplant regardless of the severity of pre-transplant hypoxaemia.Lay summaryA total of 1,152 patients with hepatopulmonary syndrome listed for liver transplant were analysed. Patients with a low PaO2 <45 mmHg had a high likelihood of transplantation. If associated with advanced liver disease, the mortality risk was higher for patients with hepatopulmonary syndrome on the wait list. After liver transplantation, patients with a PaO2 <45 mmHg had a lower survival, but this only became significant after 2.6 years, and the median survival was 11.5 years. This suggests that patients with hepatopulmonary syndrome do benefit from transplantation.

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Dataset Information

Estimated Pao₂: A Continuous and Noninvasive Method to Estimate Pao₂ and Oxygenation Index.

Objective

Derivation cohort

Validation cohort

Prediction model

Results

Conclusion

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Dataset Information

Estimated Pao2: A Continuous and Noninvasive Method to Estimate Pao2 and Oxygenation Index.

Objective

Derivation cohort

Validation cohort

Prediction model

Results

Conclusion

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Estimated Pao₂: A Continuous and Noninvasive Method to Estimate Pao₂ and Oxygenation Index.