Carbon Monoxide-induced Coma: Prognostic Factors (Coma-CO)

Prognostic Factors of Carbon Monoxide-induced Coma Treated by Hyperbaric Oxygen: a Retrospective Study

The primary objective of the study is to determine prognostic factors for hospital-mortality following carbon monoxide (CO)-induced coma. The secondary objective is to determine prognostic factors of CO related cognitive sequelae, at the time of hospital discharge.

Study Overview

• Status: Completed
• Conditions: Coma; Carbon Monoxide Poisoning

Detailed Description

Carbon monoxide is a leading cause of poison related lethality in France. Moreover, survivors may develop severe neuro-cognitive sequelae. Few studies sought to determine prognostic factors related to CO induced coma.

Coma is defined as a Glasgow coma score of < 8. Neurological sequels will be considered persistent when present at hospital discharge.

This is a retrospective observational study. All comatose patients with Glasgow coma score < 8 due to carbon monoxide poisoning, treated by hyperbaric oxygen therapy in a tertiary hospital in the Île de France area, will be included in the study. Clinical, biological, iconographic and electrophysiological data collected from patient's medical files between January 2000 to December 2018 will be analysed retrospectively.

Statistics

Base-line characteristics will be summarized using tabulated Statistics, namely median [interquartile range, IQR] or percentages (*"Statistics") unless specified.

Exact Fisher tests will be used to compare distribution of binary outcomes, while nonparametric Wilcoxon rank sum tests will be used for comparison of continuous variables.

Logistic regression models will be used to measure the strength of association of the variables with the outcomes, by odds ratio (OR), either unadjusted or adjusted in multivariable models.

Multivariate imputation by chained equations (MICE) will be used as the method of dealing with missing data in covariates. It operates under the assumption that given the variables used in the imputation procedure, the missing data are Missing At Random (MAR), which means that the probability that a value is missing depends only on observed values and not on unobserved values. A total of m = 30 imputed datasets will be generated, with Rubin's rules applied thereafter to provide mean estimates of the ORs. The package mice implemented the MICE procedure within R.

All tests are 2-sided with p-values of 0.05 or less denoting statistical significance. Statistical analysis will be performed on R 3.5.1

• Study Type: Observational
• Enrollment (Actual): 212

Contacts and Locations

Study Locations

• France
  • Garches, France, 92380
    • Intensive Care Unit, Raymond Poincaré hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

All comatose patients (Glasgow coma score <8) due to carbon monoxide poisoning, treated by hyperbaric oxygen therapy in a tertiary hospital in the greater Paris area were included in the current study

Description

Inclusion Criteria:

• All comatose patients (Glasgow coma score <8) due to carbon monoxide poisoning, treated by hyperbaric oxygen therapy in a tertiary hospital in Île de France area;
• Aged ≥ 18 years;
• Hospitalized in hyperbaric medicine unity of Raymond Poincaré hospital in Garches.

Exclusion Criteria:

• Pregnant woman;
• Patient present clinical signes of stroke and without CO detection.

In case of unusable data, patient will be excluded from study.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mortality rate	Mortality rate during the stay in hospital: patient alive or not at discharge or death	28-day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cognitive sequelae at hospital discharge	Assessment of neurological sequelae at hospital discharge: epilepsia or abnormal movements recorded in files	28-day
Cognitive sequelae at hospital discharge	Assessment of neurological sequelae at hospital discharge: motor deficit recorded in files	28-day
Cognitive sequelae at hospital discharge	Assessment of neurological sequelae at hospital discharge: disorders of consciousness recorded in files	28-day
Cognitive sequelae at hospital discharge	Assessment of neurological sequelae at hospital discharge: cognitive and psychological disorders recorded in files	28-day

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Investigators: Principal Investigator: Paris Meng, MD, Intensive Care Unit, Raymond Poincaré hospital; Study Director: Djillali ANNANE, MD, PhD, Intensive Care Unit, Raymond Poincaré hospital

Publications and helpful links

General Publications

• Resche-Rigon M, White IR. Multiple imputation by chained equations for systematically and sporadically missing multilevel data. Stat Methods Med Res. 2018 Jun;27(6):1634-1649. doi: 10.1177/0962280216666564. Epub 2016 Sep 19.

Helpful Links

• Mice : Multivariate Imputation by Chained Equations in R.
• R Development Core Team (2008). R: A language and environment for statistical computing. R Foundation for Statistical Computing
• R Development Core Team (2008)

Study record dates

Study Major Dates

• Study Start (ACTUAL): May 1, 2019
• Primary Completion (ACTUAL): June 30, 2019
• Study Completion (ACTUAL): June 30, 2019

Study Registration Dates

• First Submitted: April 15, 2019
• First Submitted That Met QC Criteria: April 23, 2019
• First Posted (ACTUAL): April 24, 2019

Study Record Updates

• Last Update Posted (ACTUAL): July 7, 2020
• Last Update Submitted That Met QC Criteria: July 1, 2020
• Last Verified: November 1, 2019

More Information

Terms related to this study

• Keywords: Hyperbaric oxygen; Oxygen; Coma; Carbon monoxide poisoning
• Additional Relevant MeSH Terms: Chemically-Induced Disorders; Nervous System Diseases; Neurologic Manifestations; Neurobehavioral Manifestations; Unconsciousness; Consciousness Disorders; Gas Poisoning; Poisoning; Carbon Monoxide Poisoning; Coma
• Other Study ID Numbers: 18PMG-COMA-CO

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No