Outcomes and Practices of Endotracheal Intubation Using the Glasgow Coma Scale in Acute Non-Traumatic Poisoning: A Systematic Review and Meta-Analysis of Proportions
Restricted accessReview articleFirst published online November, 2025
Outcomes and Practices of Endotracheal Intubation Using the Glasgow Coma Scale in Acute Non-Traumatic Poisoning: A Systematic Review and Meta-Analysis of Proportions
Acute poisoning often results in decreased consciousness, necessitating airway assessment and management. Existing literature in the trauma setting suggests the importance of airway protection in unconscious patients to prevent complications, including aspiration. Practices for endotracheal intubation in non-traumatic acute poisoning are poorly described and variable, particularly regarding the use of a Glasgow Coma Scale (GCS) ≤ 8 threshold for intubation.
Methods
A systematic review and meta-analysis of proportions was conducted to evaluate intubation rates and outcomes in patients presenting for acute non-traumatic poisoning. Studies were excluded if the primary indication for intubation was not airway protection. We analyzed rates of intubation, mortality, and aspiration by subgrouping patients into GCS ≤ 8, GCS 9–15, or mixed GCS. Common and random-effects analysis were used, supplemented by subgroup analyses.
Results
39 studies were included in the analysis, involving 15,959 patients. Random-effects pooled intubation rates varied significantly across GCS categories: GCS ≤ 8 (30.0%, I2 = 92%, p < 0.01), GCS 9–15 (1.0%, I2 = 0%, p = 0.91), and mixed GCS (11.0%, I2 = 94%, p < 0.01), p-value <0.01 for subgroup difference. Aspiration rates also varied: GCS ≤ 8 (19.0%, I2 = 84%, p < 0.01), GCS 9–15 (4.0%, I2 = 78%, p < 0.01), and mixed group (5.0%, I2 = 72%, p < 0.01), p-value <0.01 for subgroup difference. Mortality rates remained low across all groups: GCS ≤ 8 (1.0%, I2 = 0%, p = 0.62), GCS 9–15 (1.0%, I2 = 0%, p = 0.99), and mixed group (2.0%, I2 = 68%, p < 0.01).
Conclusion
The conventional “less than 8, intubate” approach may not be directly applicable to acute poisoning patients due to heterogeneity in patient presentation, intubation practices, and low mortality. Therefore, a nuanced approach is warranted to optimize airway management strategies tailored to individual patient needs.
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