6 ADVERSE REACTIONS
The following clinically significant adverse reactions have been reported and described in other sections of the labeling:
- Allergic-Type Reactions [see Contraindications (4)]
- Dose-Related Toxicity [see Warnings and Precautions (5.3)]
- Systemic Toxicities with Unintended Intravascular Injection [see Warnings and Precautions (5.4)]
- Methemoglobinemia [see Warnings and Precautions (5.5)]
- Cardiac Arrest in Obstetrical Anesthesia [see Warnings and Precautions (5.6)]
- Chondrolysis with Intra-Articular Infusion [see Warnings and Precautions (5.7)]
- Cardiac Arrest with Intravenous Regional Anesthesia Use [see Contraindications (4), Warnings and Precautions (5.8)]
The following adverse reactions from voluntary reports or clinical studies have been reported with bupivacaine. Because many of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Adverse reactions to MARCAINE SPINAL are characteristic of those associated with other amide-type local anesthetics. A major cause of adverse reactions to MARCAINE SPINAL is due to cephalad extension of the motor level of anesthesia and/or excessive plasma levels, which may be due to overdosage, unintentional intravascular injection, or slow metabolic degradation.
The most commonly encountered acute adverse reactions that demand immediate counter-measures following the administration of spinal anesthesia were hypotension due to loss of sympathetic tone and respiratory paralysis or underventilation due to cephalad extension of the motor level of anesthesia. These have led to cardiac arrest if untreated. In addition, dose-related convulsions and cardiovascular collapse have resulted from diminished tolerance, rapid absorption from the injection site, or from unintentional intravascular injection of a local anesthetic solution.
Respiratory System: Respiratory paralysis or underventilation have been noted as a result of cephalad spread of spinal anesthesia and has led to secondary hypoxic cardiac arrest when untreated. Preanesthetic medication, intraoperative anesthetics, analgesics, and sedatives, as well as surgical manipulation, may contribute to underventilation. This has usually been noted within minutes of the injection of spinal anesthetic solution, but because of differing maximal onset times, differing intercurrent drug usage, and differing surgical manipulation, it may occur at any time during surgery or the immediate recovery period.
Cardiac Disorders: Hypotension due to loss of sympathetic tone has been commonly encountered following spinal anesthesia. This has been more commonly observed in elderly patients, particularly those with hypertension, and patients with reduced blood volume, reduced interstitial fluid volume, cephalad spread of the local anesthetic, and/or mechanical obstruction of venous return. Nausea and vomiting have been frequently associated with hypotensive episodes following the administration of spinal anesthesia. High doses, or inadvertent intravascular injection, have led to high plasma levels and related depression of the myocardium, decreased cardiac output, bradycardia, heart block, ventricular arrhythmias, and cardiac arrest [see Warnings and Precautions (5.4)].
Nervous System Disorders: Respiratory paralysis or underventilation secondary to cephalad spread of the level of spinal anesthesia (see Respiratory System) and hypotension for the same reason (see Cardiac Disorders) have been the two most commonly encountered CNS-related adverse observations which demand immediate counter-measures.
High doses or inadvertent intravascular injection have led to high plasma levels and related CNS toxicity. Adverse reactions were characterized by excitation and/or depression of the CNS and included restlessness, anxiety, dizziness, tinnitus, blurred vision, tremors, convulsions, drowsiness, unconsciousness, and respiratory arrest.
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.
Convulsions: Incidence varied 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. 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.
Neurologic effects following spinal anesthesia have included loss of perineal sensation and sexual function; persistent anesthesia, paresthesia, weakness and paralysis of the lower extremities, and loss of sphincter control with slow, incomplete, or no recovery; hypotension, high or total spinal block; urinary retention; headache; backache; septic meningitis, meningismus; arachnoiditis; slowing of labor; increased incidence of forceps delivery; shivering; cranial nerve palsies due to traction on nerves from loss of cerebrospinal fluid; and fecal and urinary incontinence.
Immune System Disorders: Allergic-type reactions have occurred as a result of sensitivity to bupivacaine. These reactions were characterized by signs such as urticaria, pruritus, erythema, angioneurotic edema (including laryngeal edema), tachycardia, sneezing, nausea, vomiting, dizziness, syncope, excessive sweating, elevated temperature, and severe hypotension. Cross sensitivity among members of the amide-type local anesthetic group has been reported.