Table 1.
List of the studies included in the systematic review and their characteristics
| Study | Population | Method | Enrollment | Sampling | Setting | Sample size | Inclusion criteria | Operators | Outcome | Results |
|---|---|---|---|---|---|---|---|---|---|---|
| Non-traumatic patients | ||||||||||
| Donald [16] 2009 | Poisoned patients | Observational | Prospective | Non consecutive | ED | 26 | GCS ≤ 8 | ED physicians |
- Aspiration - Hospital LOS - Mortality |
- Aspiration: none - Hospital LOS: non-intubated group vs. intubated group (26 h vs. 5.4 days) - Mortality: non-intubated group vs. intubated group (0 vs 1) |
| Duncan [8] 2009 | Poisoned patients | Observational | Prospective | Consecutive | ED | 73 | GCS ≤ 15 | ED physicians |
- Aspiration - Admission to ICU |
- Aspiration: none - ICU admission: 1 in GCS ≤ 8 group - Hospital LOS: GCS ≤ 8 vs GCS > 8 (26 h vs 14 h) |
| Eizadi-Mood [17] 2009 | Poisoned patients | Observational | Retrospective | n.a. | ED | 155 | GCS ≤ 12 | ED physician | - Aspiration pneumonitis |
- Aspiration pneumonitis: intubation (OR = 0.07; 95%CI = 0.01–0.49) [GCS (OR = 0.43; 95%CI = 0.30–0.62)] |
| Montassier [18] 2012 | Poisoned patients | Observational | Prospective | Consecutive? | PH and ED | 72 | GCS ≤ 8 | PH and ED physicians | - Aspiration pneumonia |
- Aspiration pneumonia: 9/13 (69.2%) in delayed ED intubation group vs. 6/34 (17.7%) ED intubation group (p = 0.002). [GCS > 8 group vs GCS ≤ 8 group (6 [24%] vs 15 [31.9%]; p = 0.48)] |
| Nielsen [6] 2012 | Non-traumatic unconscious patients | Observational | Retrospective | n.a. | PH | 557 | GCS < 9 | PH physicians | - Intubation during hospitalization | - 64/557 (11%) patients remained unconscious to ED; 12 (2%) of these were intubated in the ED |
| Dietze [19] 2014 | Gamma-hydroxybutyric acid overdose patients | Observational | Retrospective | n.a. | ED | 335 | GCS ≤ 8 | ED physicians |
- ED LOS - Admission status |
- ED LOS: intubated vs. non-intubated group + 41% (Exp B = 1.41, 95%CI = 1.19 to 1.65) - Probability of hospital admission: intubated vs. non-intubated group (OR = 0.10, 95%CI = 0.02 to 0.65) |
| van Helmond [20] 2019 | Gamma-hydroxybutyric acid overdose patients | Observational | Retrospective | n.a. | ED | 158 | GCS < 9 | PH and ED physicians? | - Aspiration |
- Major aspiration events were reported in 5 patients (2.4%; 95%CI: 0.8–5.5) [2 required intubation (16.7%; 95%CI: 2.1–48.4)] |
| Trauma patients | ||||||||||
| Davis [21] 2005 | TBI | Observational | Prospective | Consecutive? | PH | 412 | GCS ≤ 8 | EMS providers |
- Pre-RSI hypoxia - Aspiration - Mortality |
- Hypoxia: before RSI vs. after RSI (23.9% vs. 5.9%, OR 4.97, 95%CI = 3.07–8.07, p = 0.001) - Aspiration: GCS ≤8 (χ2 p = 0.14; AUC = 0.55) - Mortality: GCS ≤8 (χ2 p < 0.001 AUC = 0.58) |
| Irvin11 2010 | TBI | Observational | Retrospective | n.a. | PH | 10,948 | GCS = 3 | EMS providers? | - Mortality | - Mortality rate: hospital intubated vs. prehospital intubated group (35% vs. 62%; p < 0.0001) |
| Evans [22] 2011 | TBI | Observational | Retrospective | n.a. | PH | 197 | TBI needed intubation | EMS providers? | - Pneumonia |
- GCS score in pneumonia group vs. non-pneumonia group (7.9 ± 0.9 vs 9.9 ± 0.4 p = 0.04) - Use of BVM in pneumonia group vs. non-pneumonia group (18 [56.3%] vs. 56 [34.0%]; p = 0.02) |
| Emami [23] 2019 | TBI | Observational | Retrospective | n.a. | PH | 21,242 | GCS < 9 | PH physicians | - Mortality | - Mortality: intubated vs. non-intubated group (42.2% vs. 30.0%, respectively). In patients < 15 years old (42.2% vs. 33.4%; p = 0.03) |
| Adult Mixed cases | ||||||||||
|
Steuerwald [24] 2018 |
Mixed adult patients | Observational | Retrospective | n.a. | PH | 161 | Adults patients who required airways management | EMS providers | - Aspiration | - Aspiration: 59 cases (8%) in supraglottic device group vs. 91 cases (12%) in endotracheal tube group (p value = .359; relative risk = .841; 95%CI .329–2.152) |
| Pediatric Mixed cases | ||||||||||
| Tweed [12] 2018 | Pediatric unconsciuous patients | Observational | Retrospective | n.a. | PH | 104 | Unconscious pediatric patients | EMS providers |
- Oxygenation - Mortality |
- Inadequate oxygenation: 4% in intubated group; 9% in BVM patients; 32% in only oxygen group. - Mortality: Trauma patients: intubated vs. non-intubated group (RR 0.61 [95% CI, 0.35–1.06]; P = .082). Non-traumatic patients: intubated vs. non-intubated group (RR 2.98 [95% CI, 1.18–7.56]; P = .021) |
N.a. Not available, ED Emergency Department, n.s. Not specified, TBI Traumatic brain injury, PH Pre-hospital, RSI Rapid sequence intubation, ICU Intensive care unit, LOS Length of stay, EMS Emergency medical system, GCS Glasgow Coma Scale, χ2 Chi-square, p p-value, OR Odds ratio, CI Confidence interval, AUC Area under the curve, h Hours, BVM Bag valve mask, Exp B Coefficient for the linear regression