Dosage
Dosage of lidocaine hydrochloride varies with the anesthetic procedure, the degree of anesthesia required, and individual patient response. The usual dosages should generally be reduced in children, geriatric patients, debilitated or acutely ill patients, and patients with cardiac and/or hepatic disease. The smallest dose and lowest concentration required to produce the desired effect should be used. Use of dilute solutions (i.e., 0.25-0.5%) and total dosages not to exceed 3 mg/kg are recommended for induction of IV regional anesthesia in children.
Single doses of lidocaine hydrochloride (for anesthesia other than spinal) should not exceed 4.5 mg/kg (or 300 mg) in healthy adults or 4.5 mg/kg in children younger than 10 years of age. When administered with epinephrine, lidocaine hydrochloride doses should not exceed 7 mg/kg (or 500 mg) in healthy adults or 7 mg/kg in children younger than 10 years of age. For spinal anesthesia, up to 100 mg of the drug may be given. For continuous epidural or caudal anesthesia, the maximum dose should not be repeated at intervals of less than 1.5 hours. When continuous lumbar or caudal epidural anesthesia is used for nonobstetric procedures, additional drug may be administered if necessary to attain adequate anesthesia. For paracervical block for nonobstetric and obstetric analgesia (including abortion), the maximum recommended dosage (200 mg) should not be repeated at intervals of less than 1.5 hours. For IV regional anesthesia in adults using a 0.5% solution without epinephrine, the dose administered should not exceed 4 mg/kg.
Solutions of 1-2% lidocaine hydrochloride with or without epinephrine and containing no preservatives are used for epidural or caudal anesthesia. To prevent intravascular or subarachnoid injection of a large epidural dose of lidocaine, a test dose (e.g., 2-3 mL of a 1.5% solution) of anesthetic solution should be injected at least 5 minutes prior to administering the total dose. When clinical conditions permit, use of a test dose solution that contains epinephrine (e.g., 10-15 mcg) should be considered to detect inadvertent intravascular injection. The test dose should be repeated if the patient is moved such that the epidural catheter may have been displaced. Rapid injection of a large, single dose through a catheter should be avoided; instead, the drug should be administered, when feasible, in fractional doses. In epidural anesthesia, 2-3 mL of the indicated solution is usually required for each dermatome to be anesthetized. In caudal block for production of obstetric analgesia or in epidural thoracic block, 20-30 mL of a 1% solution (200-300 mg) of the drug may be used. For surgical anesthesia with caudal block, 15-20 mL of a 1.5% solution (225-300 mg) is given. For epidural lumbar analgesia, the dose is 25-30 mL (250-300 mg) of a 1% solution, and for epidural lumbar anesthesia, the recommended dose is 15-20 mL of a 1.5% solution (225-300 mg) or 10-15 mL of a 2% solution (200-300 mg).
A solution of 5% lidocaine hydrochloride with 7.5% dextrose is used for spinal anesthesia in adults and adolescents 16 years of age or older. For obstetric low spinal or saddle-block anesthesia in a normal vaginal delivery, the dose is approximately 1 mL (50 mg). For cesarean section or deliveries which require intrauterine manipulations, 1.5 mL of the 5% solution (75 mg) may be given. For surgical anesthesia, 1.5-2 mL of the 5% solution (75-100 mg) may be administered.
The following doses of lidocaine hydrochloride have been suggested for various nerve blocks: brachial nerve block, 15-20 mL of a 1.5% solution (225-300 mg); dental nerve block, 1-5 mL of a 2% solution (20-100 mg); intercostal nerve block, 3 mL of a 1% solution (30 mg); paravertebral nerve block, 3-5 mL of a 1% solution (30-50 mg); pudendal nerve block (each side), 10 mL of a 1% solution (100 mg); and paracervical nerve block (each side) for obstetric analgesia, 10 mL of a 1% solution (100 mg). For sympathetic nerve blocks, the following doses may be used: cervical (stellate ganglion) nerve block, 5 mL of a 1% solution (50 mg), and lumbar nerve block, 5-10 mL of a 1% solution (50-100 mg). For percutaneous infiltration anesthesia, the dose of lidocaine hydrochloride is 1-60 mL of a 0.5 or 1% solution (5-300 mg). For IV regional anesthesia, 10-60 mL of a 0.5% solution (50-300 mg) may be employed.
For retrobulbar injection, 3-5 mL of a 4% sterile solution (120-200 mg) or 1.7-3 mg/kg is suggested; a portion of the dose is injected retrobulbarly and the remainder may be used to block the facial nerve.
For transtracheal injection, 2-3 mL of a 4% solution (80-120 mg) is administered rapidly. When both transtracheal injection and topical application (oropharyngeal spray) of a 4% solution are needed to achieve complete analgesia, the combined total dose of lidocaine hydrochloride administered by injection and by oropharyngeal spray should not exceed 5 mL of a 4% solution (200 mg) or 3 mg/kg.
Lidocaine hydrochloride with or without epinephrine is used for various dental procedures by infiltration injection or nerve block. In oral infiltration and/or mandibular block, initial doses of 1-5 mL of 2% lidocaine hydrochloride (20-100 mg) with epinephrine 1:100,000 are usually effective. If greater hemostasis is required, epinephrine 1:50,000 may be used. In children younger than 10 years of age, 0.9-1 mL of 2% lidocaine hydrochloride (18-20 mg) is adequate for a procedure involving 1 tooth (local infiltration), 2-3 teeth (maxillary infiltration), or teeth in an entire quadrant (mandibular block).