From the Guidelines
Effect of Neuraxial Anesthesia on Heart Rate
Neuraxial anesthesia decreases heart rate due to the sympathetic blockade it induces, which reduces cardiac sympathetic drive and subsequently myocardial contractility and cardiac loading conditions 1.
- The reduction in heart rate is a result of the blockade reaching the thoracic dermatome level 4, affecting cardiac sympathetic drive.
- This effect is beneficial for patients with cardiovascular risk factors or diseases, as neuraxial anesthesia and analgesia may be considered for their management 1.
- The decrease in heart rate can vary depending on the dose and duration of the neuraxial anesthesia, but it is generally associated with a reduction in myocardial contractility and change in cardiac loading conditions 1.
- The use of neuraxial anesthesia, such as spinal or epidural anesthesia, can provide a reduction in cardiac complications and is considered a viable option for patients undergoing non-cardiac surgery, especially those with cardiovascular diseases 1.
From the FDA Drug Label
The most commonly encountered acute adverse experiences that demand immediate countermeasures are related to the central nervous system and the cardiovascular system These adverse experiences are generally dose-related and due to high plasma levels that may result from overdosage, rapid absorption from the injection site, diminished tolerance or from unintentional intravascular injection of the local anesthetic solution In addition to systemic dose-related toxicity, unintentional subarachnoid injection of drug during the intended performance of lumbar epidural block or nerve blocks near the vertebral column (especially in the head and neck region) may result in underventilation or apnea (“Total or High Spinal”) Also, hypotension due to loss of sympathetic tone and respiratory paralysis or underventilation due to cephalad extension of the motor level of anesthesia may occur. This may lead to secondary cardiac arrest if untreated Factors influencing plasma protein binding, such as acidosis, systemic diseases that alter protein production or competition with other drugs for protein binding sites, may diminish individual tolerance. If not treated immediately, convulsions with simultaneous hypoxia, hypercarbia, and acidosis plus myocardial depression from the direct effects of the local anesthetic may result in cardiac arrhythmias, bradycardia, asystole, ventricular fibrillation, or cardiac arrest.
The effect of neuraxial anesthesia on heart rate is that it may cause bradycardia due to hypotension and loss of sympathetic tone, as well as cardiac arrhythmias, asystole, ventricular fibrillation, or cardiac arrest if not treated immediately 2 3.
From the Research
Effect of Neuraxial Anesthesia on Heart Rate
- The provided studies do not directly address the effect of neuraxial anesthesia on heart rate.
- However, some studies mention the effects of neuraxial anesthesia on other hemodynamic parameters, such as blood pressure and hypotension 4, 5.
- One study found that the use of neuraxial neostigmine was not associated with an increase in the incidence of hypotension, dizziness, or sedation 4.
- Another study found that the use of low-dose sufentanil with local anesthetics in elderly patients undergoing lower limb surgery resulted in a lower incidence of hypotension and a more stable hemodynamic profile 5.
- There is no direct evidence in the provided studies to suggest a specific effect of neuraxial anesthesia on heart rate.
- Further research would be needed to determine the effects of neuraxial anesthesia on heart rate.