Ketamine Use in COPD Patients Requiring Rapid Sequence Intubation

Introduction to Ketamine Use in COPD

The American Society of Anesthesiologists recommends ketamine for COPD patients undergoing rapid sequence intubation (RSI) due to its bronchodilation benefits, but with caution due to potential downsides including increased upper airway secretions and paradoxical hypotension 1, 2

Ketamine significantly increases upper airway secretions in COPD patients, which can worsen dyspnea, and requires anticholinergic pretreatment with atropine or glycopyrrolate to attenuate these effects 1
The increased secretions require aggressive suctioning capability and preparation, as COPD patients already have compromised airway clearance mechanisms 3

Despite ketamine's sympathomimetic properties, paradoxical hypotension can occur in critically ill COPD patients with depleted catecholamine stores from prolonged respiratory distress, chronic hypoxemia, or concurrent sepsis 2, 4

The American College of Chest Physicians recommends using the lower end of ketamine dosing (1 mg/kg IV) in COPD patients with any hemodynamic compromise, chronic cor pulmonale, or signs of right ventricular dysfunction to minimize hypotension risk while maintaining adequate sedation 2, 4
Administer anticholinergic premedication (glycopyrrolate 0.2 mg or atropine 0.5 mg) 3-5 minutes before ketamine to prevent secretion-related complications 1, 2

No mortality difference exists between ketamine and etomidate in critically ill patients undergoing RSI, though etomidate causes transient adrenal suppression without demonstrated negative clinical outcomes 5, 4
Propofol and thiopental carry worse profiles for COPD patients: propofol causes profound myocardial depression and vasodilation, while thiopental can cause severe bronchoconstriction in the presence of cholinergic stimulation or preexisting reactive airway disease 1, 2

Never assume ketamine's sympathomimetic properties guarantee hemodynamic stability—COPD patients with chronic hypoxemia, cor pulmonale, or concurrent sepsis may have exhausted endogenous catecholamine stores 2
Ensure adequate preoxygenation before ketamine administration, as COPD patients have reduced functional residual capacity and desaturate rapidly despite ketamine's theoretical preservation of respiratory drive 6, 7

The Society of Critical Care Medicine found no mortality difference between ketamine and etomidate in critically ill patients undergoing RSI, despite etomidate causing transient adrenal suppression 8
The Society of Critical Care Medicine recommends preoxygenation with high-flow nasal oxygen (HFNO) when laryngoscopy is expected to be challenging, or noninvasive positive pressure ventilation (NIPPV) in patients with severe hypoxemia (PaO2/FiO2 < 150) 8

The Society of Critical Care Medicine found mixed results regarding peri-intubation hemodynamics between etomidate and ketamine, with no difference in duration of vasopressor use 8

Etomidate has no bronchodilatory properties and provides no respiratory advantage in obstructive lung disease, whereas ketamine offers a critical advantage in patients with baseline airflow obstruction 9

The Society of Critical Care Medicine's 2023 guidelines analyzed multiple studies showing no difference in 28-day mortality (OR 0.95; 95% CI: 0.72-1.25) or hospital mortality between ketamine and etomidate in critically ill patients undergoing RSI 9
No mortality difference exists between ketamine and etomidate in critically ill patients undergoing RSI, making the decision hinge on disease-specific advantages rather than survival outcomes 9

Midazolam has a longer onset of action compared to both ketamine and etomidate and is a potent venodilator at RSI doses, limiting its utility 9

Etomidate's hemodynamic neutrality is its only advantage, but this becomes irrelevant when compared to ketamine's disease-specific bronchodilation benefit in COPD patients 9
While etomidate causes transient adrenal suppression (OR: 2.43; 95% CI: 1.67-3.53 for adrenal insufficiency), this has not been demonstrated to cause negative clinical outcomes, and corticosteroid administration following etomidate is not recommended 9
The adrenal suppression concern has been extensively studied without demonstrating increased mortality or worse outcomes in critically ill patients 9

The Society of Critical Care Medicine guidelines suggest that ketamine is associated with mixed results regarding peri-intubation hemodynamics compared to etomidate, with no difference in vasopressor duration or mortality, in critically ill patients, including those with COPD 10, 11
Ensuring adequate preoxygenation with high-flow nasal oxygen (HFNO) or noninvasive positive pressure ventilation (NIPPV) if PaO₂/FiO₂ < 150 is crucial when laryngoscopy is expected to be challenging in COPD patients, as recommended by the Society of Critical Care Medicine 10, 11