Evaluation of Physiologic Alterations during Prehospital Paramedic-Performed Rapid Sequence Intubation

Figures & data

Figure 1. Flow diagram of cases analyzed in the study.

Table 1. Patient and airway management process characteristics, grouped by paramedic-assigned prehospital diagnostic impression category^*

	All Cases (n = 134)	Neurologic (n = 56)	Respiratory (n = 35)	Toxicologic (n = 30)	Trauma (n = 12)	Cardiac (n = 1)
Patient
Male sex	68 (51%)	24 (43%)	20 (57%)	16 (53%)	8 (67%)	—
Age (y)	55 (36, 68)	60 (39, 71)	64 (56, 70)	42 (31, 50)	32 (29, 40)	62
Weight (kg)	80 (68, 100)	80 (70, 100)	80 (63, 100)	80 (69, 100)	80 (64, 100)	82
RSI location
On scene	101 (75%)	40 (71%)	29 (83%)	24 (80%)	8 (67%)	—
During transport	33 (25%)	16 (29%)	6 (17%)	6 (20%)	4 (33%)	1
RSI Indication
Airway protection	97 (72%)	52 (93%)	7 (20%)	29 (97%)	9 (75%)	—
Respiratory failure	35 (26%)	3 (5%)	27 (77%)	1 (3%)	3 (25%)	1
None documented	2 (1%)	1 (2%)	1 (3%)	0 (0%)	0 (0%)	—
Induction agent
Etomidate	91 (68%)	39 (70%)	23 (66%)	21 (70%)	8 (67%)	—
Dose (mg/kg)	0.3 (0.3, 0.3)	0.3 (0.3, 0.3)	0.3 (0.3, 0.3)	0.3 (0.3, 0.4)	0.3 (0.3, 0.4)	—
Midazolam	37 (28%)	16 (29%)	10 (28%)	7 (23%)	3 (25%)	1
Dose (mg)	5 (3, 5)	5 (2, 5)	5 (4, 5)	4 (2, 5)	5 (4, 5)	5
None documented	6 (4%)	1 (1%)	2 (6%)	2 (7%)	1 (8%)	—
Paralytic agent
Succinylcholine	129 (96%)	52 (93%)	35 (100%)	29 (97%)	12 (100%)	1
Dose (mg/kg)	1.6 (1.5, 1.9)	1.6 (1.5, 1.9)	1.6 (1.5, 1.9)	1.6 (1.5, 1.8)	1.7 (1.6, 2.0)	1.7
Rocuronium	5 (4%)	4 (7%)	0 (0%)	1 (3%)	0 (0%)	—
Dose (mg/kg)	0.7 (0.6, 0.9)	0.7 (0.6, 0.8)	—	0.9	—	—
Pretreatment
Lidocaine	16 (12%)	7 (13%)	0 (0%)	1 (3%)	8 (67%)	—
Intubation success rate
First attempt	110 (82%)	44 (79%)	29 (83%)	25 (83%)	11 (92%)	1 (100%)
Overall	127 (95%)	52 (93%)	34 (97%)	28 (93%)	12 (100%)	1 (100%)

^* Data are reported as n (%) or median (25th, 75th percentile).

Figure 2. Percentage of cases (with 95% confidence interval) in each prehospital diagnostic impression category with any desaturation (light grey) and severe desaturation (dark grey). Median (25th, 75th percentile) pre-intubation SpO₂ maximum is indicated below each category. There was loss of SpO₂ data in the 1 cardiac case; thus, results are only depicted for the remaining 4 categories.

Figure 3. Probability (with 95% confidence interval) of any desaturation (light grey) and severe desaturation (dark grey) associated with different ranges of maximum pre-intubation SpO₂. Median (25th, 75th percentile) change in SpO₂ from pre-intubation maximum to nadir during intubation is indicated below each SpO₂ range.

Figure 4. SpO₂ nadir and desaturation duration for all desaturation events, grouped by prehospital diagnostic impression category.

Figure 5. Paired maximum pre-intubation SpO₂ and nadir SpO₂ during intubation for (A) cases with first-attempt intubation success and (B) cases with multiple intubation attempts. Some paired values represent multiple cases with the same maximum and nadir SpO₂ measurements.