Prolonging paracervical block anesthesia: addition of dextran to 2-chloroprocaine

Forty parturient women received paracervical block (PCB) anesthetics during labor with 2-chloroprocaine (2-CP) and epinephrine in either normal saline or dextran. Thirty-six patients were though to have adequate anesthesia. Nineteen patients who recived 2-CP in saline had a mean duration of anesthesia lasting 55.4 min; one fetus developed post-PCB bradycardia. Seventeen patients who received 2-CP in dextran had a mean duration of anesthesia lasting 72.7 min; no fetal bradycardia was observed following PCB. Neonatal depression, expressed by 1 and 5 min Apgar scores below seven, was not observed in either group. The addition of dextran to 2-CP significantly prolongs the duration of PCB anesthesia and does not appear to compromise the fetus. The pain relief provided by a single PCB with 2-CP in dextran is still relatively short and would not persist throughout the active phase of labor in most parturient women.