med, the type and amount of drug used, and the technique
of drug administration. Adverse reactions in the parturient, fetus and neonate involve alterations of the central nervous system,
peripheral vascular tone and cardiac function.
Maternal hypotension has resulted from regional anesthesia. Local anesthetics produce vasodilation by blocking sympathetic nerves.
Elevating the patient’s legs and positioning her on her left side will help prevent decreases in blood pressure.
The fetal heart rate also should be monitored continuously, and electronic fetal monitoring is highly advisable.
Epidural, spinal, paracervical, or pudendal anesthesia may alter the forces of parturition through changes in uterine contractility or
maternal expulsive efforts. In one study, paracervical block anesthesia was associated with a decrease in the mean duration of first
stage labor and facilitation of cervical dilation. However, spinal and epidural anesthesia have also been reported to prolong the second
stage of labor by removing the parturient’s reflex urge to bear down or by interfering with motor function. The use of obstetrical
anesthesia may increase the need for forceps assistance.
The use of some local anesthetic drug products during labor and delivery may be followed by diminished muscle strength and tone
for the first day or two of life. The long-term significance of these observations is unknown. Fetal bradycardia may occur in 20 to
30 percent of patients receiving paracervical nerve block anesthesia with the amide-type local anesthetics and may be associated with
fetal acidosis. Fetal heart rate should always be monitored during paracervical anesthesia. The physician should weigh the possible
advantages against risks when considering a paracervical block in prematurity, toxemia of pregnancy, and fetal distress. Careful
adherence to recommended dosage is of the utmost importance in obstetrical paracervical block. Failure to achieve adequate analgesia
with recommended doses should arouse suspicion of intravascular or fetal intracranial injection. Cases compatible with unintended
fetal intracranial injection of local anesthetic solution have been reported following intended paracervical or pudendal block or both.
Babies so affected present with unexplained neonatal depression at birth, which correlates with high local anesthetic serum levels,
and often manifest seizures within six hours. Prompt use of supportive measures combined with forced urinary excretion of the local
anesthetic has been used successfully to manage this complication.
Case reports of maternal convulsions and cardiovascular collapse following use of some local anesthetics for paracervical block in
early pregnancy (as anesthesia for elective abortion) suggest that systemic absorption under these circumstances may be rapid. The
recommended maximum dose of each drug should not be exceeded. Injection should be made slowly and with frequent aspiration.
Allow a 5-minute interval between sides.
Nursing Mothers
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be
exercised when lidocaine HCl is administered to a nursing woman.
Pediatric Use
Dosages in children should be reduced, commensurate with age, body weight and physical condition, see DOSAGE AND
ADMINISTRATION.
ADVERSE REACTIONS
Systemic
A |
