From the Guidelines
Rocuronium does not directly cause bradycardia as a typical side effect, and its use is not commonly associated with abnormally slow heart rates. This is based on the pharmacological profile of rocuronium, a nondepolarizing neuromuscular blocking agent (NMBA) with a monoquaternary steroidal chemistry, which has an intermediate duration of action and a very rapid onset 1. When given as a bolus dose of 0.6 –1.0 mg/kg, blockade is almost always achieved within two minutes, with maximum blockade occurring within three minutes, without significant direct effects on heart rate.
Some key points to consider about rocuronium include:
- Its rapid onset and intermediate duration of action make it a preferred choice in many clinical settings
- The drug's metabolite, 17-desacetylrocuronium, has only 5–10% activity compared with the parent compound, suggesting minimal metabolic contribution to potential side effects like bradycardia
- Continuous infusions of rocuronium are begun at 10 µg/kg/min, a dosage that is not typically associated with significant cardiovascular effects, including bradycardia
It's crucial to differentiate between the direct effects of rocuronium and other factors that may contribute to bradycardia during its use, such as:
- Histamine release, although this is uncommon
- Effects of anesthetic agents
- Surgical stimulation
- Pre-existing patient conditions
Monitoring vital signs, including heart rate, is standard practice when administering rocuronium, typically given in doses of 0.6-1.2 mg/kg for intubation. If bradycardia occurs, considering other potential causes and managing accordingly is essential, rather than attributing it solely to rocuronium 1. The lack of significant direct cardiovascular effects, including bradycardia, is a reason rocuronium is often preferred in situations where hemodynamic stability is crucial.
From the FDA Drug Label
Hemodynamics There were no dose-related effects on the incidence of changes from baseline (30% or greater) in mean arterial blood pressure (MAP) or heart rate associated with rocuronium bromide administration over the dose range of 0.12 to 1. 2 mg/kg (4 x ED95) within 5 minutes after rocuronium bromide administration and prior to intubation. Increases or decreases in MAP were observed in 2% to 5% of geriatric and other adult patients, and in about 1% of pediatric patients. Heart rate changes (30% or greater) occurred in 0% to 2% of geriatric and other adult patients.
Tachycardia (30% or greater) occurred in 12 of 127 pediatric patients Most of the pediatric patients developing tachycardia were from a single study where the patients were anesthetized with halothane and who did not receive atropine for induction
Rocuronium and Bradycardia: There is no direct information in the provided drug labels that supports the occurrence of bradycardia (abnormally slow heart rate) as an effect of rocuronium administration. The information provided discusses changes in heart rate, including tachycardia, but does not mention bradycardia. Therefore, based on the provided drug labels, no conclusion can be drawn regarding the potential of rocuronium to cause bradycardia 2.
From the Research
Rocuronium and Bradycardia
- Rocuronium is a nondepolarizing neuromuscular blocking agent that has been studied for its effects on heart rate and hemodynamics 3, 4.
- A study published in 1994 found no statistically significant hemodynamic effects, including heart rate, after administration of rocuronium 3.
- Another study published in 1997 noted that rocuronium does not produce active metabolites and has hemodynamic stability, allowing it to be used in high-risk patients 4.
- However, a study published in 1999 compared the effect of rocuronium and vecuronium on heart rate during gynaecological laparoscopy and found that patients given rocuronium had significantly fewer episodes of bradycardia than patients given vecuronium 5.
- A more recent study published in 2021 found that rocuronium dosed ≥1.4 mg/kg was associated with higher first-attempt success when using direct laryngoscopy, but did not specifically address the incidence of bradycardia 6.
- Another study published in 2014 found that high-dose rocuronium prolonged the QTc interval after intubation, which may be a concern in patients with existing myocardial damage, but did not specifically address the incidence of bradycardia 7.
Key Findings
- Rocuronium has been found to have minimal effects on heart rate in some studies 3, 4.
- However, one study found that rocuronium resulted in significantly fewer episodes of bradycardia compared to vecuronium 5.
- The relationship between rocuronium dosing and bradycardia is not fully understood and may require further study 6, 7.