ICU sedation

In two pivotal Phase III clinical trials of ICU patients treated with Precedex, the largest mean decrease in heart rate was approximately 7% and the largest mean decreases in systolic and diastolic blood pressures were 10% and 11%, respectively.13

Procedural sedation

Precedex has been studied in two pivotal Phase III clinical trials of nonintubated patients receiving monitored anesthesia care (MAC) sedation for a variety of surgical procedures as well as in patients undergoing awake fiberoptic intubation.1

The table below shows the frequency at which Precedex-sedated patients undergoing MAC sedation may experience hypotension or bradycardia and the frequency at which certain types of interventions may be needed to manage these adverse events.

Incidence and interventions for hypotension, bradycardia in patients undergoing procedural sedation15

Treatment options for drug-induced bradycardia or hypotension

In Precedex clinical trials, atropine, glycopyrrolate and ephedrine were effective in the treatment of most episodes of Precedex-induced bradycardia. However, in some patients with significant cardiovascular dysfunction, more advanced resuscitative measures were required.1,15

Glycopyrrolate dosing for drug-induced bradycardia or hypotension

Glycopyrrolate Injection may be used during surgery to counteract drug-induced or vagal reflexes and their associated arrhythmias (e.g., bradycardia). It should be administered intravenously as single doses of 0.1 mg (0.5 mL) and repeated, as needed, at intervals of 2 to 3 minutes.16

Atropine dosing for drug-induced bradycardia or hypotension

Initial single doses in adults vary from around 0.5 to 1 mg (5-10 mL of a 0.1 mg/mL solution). Administration of less than 0.5 mg can produce a paradoxical bradycardia because of the central or peripheral parasympathomimetic effects of low doses in adults.17

When the recurrent use of atropine is essential in patients with coronary artery disease, the total dose should be restricted to 2 to 3 mg (maximum 0.03-0.04 mg/kg) to avoid the detrimental effects of atropine-induced tachycardia on myocardial oxygen demand. For patients with bradyasystolic cardiac arrest, a 1 mg dose of atropine is administered intravenously and is repeated every 3 to 5 minutes if asystole persists. Three milligrams (0.04 mg/kg) given IV is a fully vagolytic dose in most patients. The administration of this dose of atropine should be reserved for patients with bradyasystolic cardiac arrest. Endotracheal administration of atropine can be used in patients without IV access. The recommended adult dose of atropine for endotracheal administration is 1 to 2 mg diluted to a total not to exceed 10 mL of sterile water or normal saline.17

Ephedrine dosing for drug-induced bradycardia or hypotension

Ephedrine is indicated to counteract the hypotensive effects of spinal or other types of nontopical conduction anesthesia. Depending on the clinical circumstances, Ephedrine Sulfate Injection may be given subcutaneously, intramuscularly or intravenously. Usual adult dose: 25 to 50 mg (range 10 to 50 mg) injected subcutaneously or intramuscularly (equivalent to 0.2 to 1 mL of 5% solution) is usually adequate to prevent or minimize hypotension secondary to spinal anesthesia. Repeat doses should be governed by blood pressure responses. Absorption (onset of action) by the intramuscular route is more rapid (within 10 to 20 minutes) than by subcutaneous injection. The intravenous route may be used if an immediate effect is desired.18