Mechanism of Action
CLINICAL PHARMACOLOGY Local anesthetics block the generation and the conduction of nerve impulses, presumably by increasing the threshold for electrical excitation in the nerve, by slowing the propagation of the nerve impulse, and by reducing the rate of rise of the action potential. In general, the progression of anesthesia is related to the diameter, myelination, and conduction velocity of affected nerve fibers. Clinically, the order of loss of nerve function is as follows: (1) pain, (2) temperature, (3) touch, (4) proprioception, and (5) skeletal muscle tone. Systemic absorption of local anesthetics produces effects on the cardiovascular and central nervous systems (CNS).
Indications
- INDICATIONS & USAGE Sensorcaine (bupivacaine HCl) is indicated for the production of local or regional anesthesia or analgesia for surgery, dental and oral surgery procedures, diagnostic and therapeutic procedures, and for obstetrical procedures. Only the 0.25% and 0.5% concentrations are indicated for obstetrical anesthesia (see WARNINGS ). Experience with nonobstetrical surgical procedures in pregnant patients is not sufficient to recommend use of the 0.75% concentration of bupivacaine HCl in these patients.
Common Doses
- DOSAGE & ADMINISTRATION The dose of any local anesthetic administered varies with the anesthetic procedure, the area to be anesthetized, the vascularity of the tissues, the number of neuronal segments to be blocked, the depth of anesthesia and degree of muscle relaxation required, the duration of anesthesia desired, individual tolerance, and the physical condition of the patient. The smallest dose and concentration required to produce the desired result should be administered.
Contraindications
- CONTRAINDICATIONS Sensorcaine (bupivacaine HCl) is contraindicated in obstetrical paracervical block anesthesia. Its use in this technique has resulted in fetal bradycardia and death. Sensorcaine is contraindicated in patients with a known hypersensitivity to it or to any local anesthetic agent of the amide-type or to other components of bupivacaine solutions.
Side Effects
- 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.