From the FDA Drug Label
ADVERSE REACTIONS: ... Reactions to Sensorcaine (bupivacaine HCl) are characteristic of those associated with other amide-type local anesthetics. A major cause of adverse reactions to this group of drugs is excessive plasma levels, which may be due to overdosage, unintentional intravascular injection, or slow metabolic degradation The most commonly encountered acute adverse experiences which demand immediate counter-measures are related to the central nervous system and the cardiovascular system These adverse experiences are generally dose related and due to high plasma levels which 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 caudal or 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. Central Nervous System Reactions These are characterized by excitation and/or depression Restlessness, anxiety, dizziness, tinnitus, blurred vision, or tremors may occur, possibly proceeding to convulsions. However, excitement may be transient or absent, with depression being the first manifestation of an adverse reaction. This may quickly be followed by drowsiness merging into unconsciousness and respiratory arrest Other central nervous system effects may be nausea, vomiting, chills, and constriction of the pupils. The incidence of convulsions associated with the use of local anesthetics varies with the procedure used and the total dose administered. In a survey of studies of epidural anesthesia, overt toxicity progressing to convulsions occurred in approximately 0. 1% of local anesthetic administrations Cardiovascular System Reactions High doses or unintentional intravascular injection may lead to high plasma levels and related depression of the myocardium, decreased cardiac output, heartblock, hypotension, bradycardia, ventricular arrhythmias, including ventricular tachycardia and ventricular fibrillation, and cardiac arrest Allergic Allergic-type reactions are rare and may occur as a result of sensitivity to the local anesthetic or to other formulation ingredients, such as the sulfites in epinephrine-containing solutions These reactions are characterized by signs such as urticaria, pruritus, erythema, angioneurotic edema (including laryngeal edema), tachycardia, sneezing, nausea, vomiting, dizziness, syncope, excessive sweating, elevated temperature, and possibly, anaphylactoid-like symptomatology (including severe hypotension) Neurologic The incidences of adverse neurologic reactions associated with the use of local anesthetics may be related to the total dose of local anesthetic administered and are also dependent upon the particular drug used, the route of administration, and the physical status of the patient Many of these effects may be related to local anesthetic techniques, with or without a contribution from the drug. In the practice of caudal or lumbar epidural block, occasional unintentional penetration of the subarachnoid space by the catheter or needle may occur Subsequent adverse effects may depend partially on the amount of drug administered intrathecally and the physiological and physical effects of a dural puncture. A high spinal is characterized by paralysis of the legs, loss of consciousness, respiratory paralysis, and bradycardia Neurologic effects following epidural or caudal anesthesia may include spinal block of varying magnitude(including high or total spinal block); hypotension secondary to spinal block; urinary retention; fecal and urinary incontinence; loss of perineal sensation and sexual function; persistent anesthesia, paresthesia, weakness, paralysis of the lower extremities and loss of sphincter control all of which may have slow, incomplete, or no recovery; headache; backache; septic meningitis; meningismus; slowing of labor; increased incidence of forceps delivery; and cranial nerve palsies due to traction on nerves from loss of cerebrospinal fluid Neurologic effects following other procedures or routes of administration may include persistent anesthesia, paresthesia, weakness, paralysis, all of which may have slow, incomplete, or no recovery.
The side effects of intrathecal bupivacaine administration include:
- Central Nervous System Reactions:
- Restlessness
- Anxiety
- Dizziness
- Tinnitus
- Blurred vision
- Tremors
- Convulsions
- Nausea
- Vomiting
- Chills
- Constriction of the pupils
- Cardiovascular System Reactions:
- High plasma levels
- Depression of the myocardium
- Decreased cardiac output
- Heartblock
- Hypotension
- Bradycardia
- Ventricular arrhythmias
- Cardiac arrest
- Allergic Reactions:
- Urticaria
- Pruritus
- Erythema
- Angioneurotic edema
- Tachycardia
- Sneezing
- Nausea
- Vomiting
- Dizziness
- Syncope
- Excessive sweating
- Elevated temperature
- Neurologic Effects:
- Spinal block of varying magnitude
- Hypotension secondary to spinal block
- Urinary retention
- Fecal and urinary incontinence
- Loss of perineal sensation and sexual function
- Persistent anesthesia
- Paresthesia
- Weakness
- Paralysis of the lower extremities
- Loss of sphincter control
- Headache
- Backache
- Septic meningitis
- Meningismus
- Slowing of labor
- Increased incidence of forceps delivery
- Cranial nerve palsies due to traction on nerves from loss of cerebrospinal fluid 1
From the Research
Intrathecal bupivacaine administration can cause several side effects, including hypotension, bradycardia, nausea, vomiting, urinary retention, and pruritus, with the most recent and highest quality study suggesting that lower doses of bupivacaine are associated with less risk of hypotension and faster recovery 2.
Common Side Effects
- Hypotension (low blood pressure) due to sympathetic blockade, affecting 20-30% of patients
- Bradycardia (slow heart rate)
- Nausea and vomiting
- Urinary retention requiring catheterization in some cases
- Pruritus (itching)
Serious Complications
- High or total spinal anesthesia if the medication spreads too high, causing respiratory depression, unconsciousness, and cardiovascular collapse
- Neurological complications, including transient neurological symptoms (TNS) characterized by pain or dysesthesia in the buttocks, thighs, or calves, typically resolving within 72 hours
- Rarely, permanent neurological injury, cauda equina syndrome, or meningitis may occur
Risk Factors
- Dosage: lower doses are associated with less risk of hypotension and faster recovery 2
- Baricity of the solution
- Patient positioning
- Individual patient factors, such as age and comorbidities
Recommendations
- Proper technique, appropriate dosing (typically 10-15mg for surgical anesthesia), and vigilant monitoring are essential to minimize risks
- Initiating intrathecal bupivacaine at doses of 5 mg/day for catheter tips in the cervical spine, 8 mg/day for catheter tips at T1-4, and 10 mg/day for catheter tips at T5-8, with close follow-up of the patient, may allow for safe and effective analgesia 3