Table 2. Characteristics of the Tracheal Intubation Procedures.
| Characteristic | Fluid bolus (n = 538) | No fluid bolus (n = 527) | Difference (95% CI)a |
|---|---|---|---|
| Intravenous fluids | |||
| Fluid bolus initiated prior to induction of anesthesia, No. (%) | 535 (99.4) | 6 (1.1) | Absolute, 98.3 (97.0 to 99.6) |
| Volume of fluid infused between enrollment and 2 minutes after tracheal intubation | (n = 536) | (n = 526) | |
| Median (IQR), mL | 500 (300 to 500) | 0 (0 to 0) | Median, 500 (450 to 500) |
| Per body weight, median (IQR), mL/kg | 5.0 (3.5 to 6.8) | 0 (0 to 0) | Median, 5.0 (4.8 to 5.3) |
| New or additional fluid bolus initiated after induction of anesthesia for the treatment of hypotension, No. (%) | 20 (3.7) | 31 (5.9) | Absolute, −2.2 (−4.9 to 0.6) |
| Management of tracheal intubation | |||
| Preoxygenation method, No. (%)b | |||
| Bilevel positive airway pressure | 161 (29.9) | 148 (28.1) | Absolute, 1.8 (−3.8 to 7.5) |
| Bag-mask device | 151 (28.1) | 173 (32.8) | Absolute, −4.8 (−10.5 to 0.9) |
| Nonrebreather mask | 133 (24.7) | 129 (24.5) | Absolute, 0.2 (−5.1 to 5.6) |
| High-flow nasal cannula | 102 (19.0) | 95 (18.0) | Absolute, 0.9 (−3.9 to 5.8) |
| Standard nasal cannula | 55 (10.2) | 43 (8.2) | Absolute, 2.1 (−1.6 to 5.7) |
| Did not receive preoxygenation | 4 (0.7) | 2 (0.4) | Absolute, 0.4 (−0.7 to 1.4) |
| Vasopressor bolus or infusion administered between enrollment and induction of anesthesia for prevention of hypotension, No. (%)c | (n = 538) 66 (12.3) |
(n = 526) 62 (11.8) |
Absolute, 0.5 (−3.6 to 4.6) |
| Oxygen saturation at induction of anesthesia, median (IQR), % | (n = 531) 99 (96 to 100) |
(n = 521) 99 (96 to 100) |
Median, 0 (−0 to 1.0) |
| Systolic blood pressure at induction of anesthesia, median (IQR), mm Hg | (n = 538) 128 (110 to 147) |
(n = 526) 126 (110 to 145) |
Median, 2.0 (−2.0 to 6.5) |
| Induction agent, No. (%)d | 536 (99.6) | 526 (99.8) | Absolute, −0.2 (−1.0 to 0.6) |
| Etomidate | 413 (76.8) | 416 (78.9) | Absolute, −2.2 (−7.3 to 3.0) |
| Ketamine | 66 (12.3) | 55 (10.4) | Absolute, 1.8 (−2.2 to 5.8) |
| Propofol | 53 (9.9) | 57 (10.8) | Absolute, −1.0 (−4.8 to 2.9) |
| Neuromuscular blocking agent, No. (%)e | 509 (94.6) | 492 (93.4) | Absolute, 1.3 (−1.8 to 4.3) |
| Rocuronium | 402 (74.7) | 378 (71.7) | Absolute, 3.0 (−2.5 to 8.5) |
| Succinylcholine | 105 (19.5) | 109 (20.7) | Absolute, −1.2 (−6.2 to 3.8) |
| Positive pressure ventilation delivered between induction of anesthesia and laryngoscopy, No. (%)f | 526 (97.8) | 513 (97.3) | Absolute, 0.4 (−1.6 to 2.5) |
a
The absolute differences are expressed as percentages.
b
Patients could receive more than 1. Preoxygenation via bag mask with concurrent ventilation and noninvasive ventilation were considered positive pressure ventilation mechanisms, whereas provision of bag-mask preoxygenation without ventilation was not (eFigure 4 in Supplement 2).
c
As either a 1-time bolus, a new infusion, or an increased rate of infusion for the purpose of preventing procedural hypotension.
d
Patients could receive more than 1. A complete list and the dosages appear in eTable 6 in Supplement 2.
e
A complete list and the dosages appear in eTable 6 in Supplement 2.
f
Included ventilation provided through a bag-mask device or a noninvasive ventilator.