The PAIN (Pelvic Area Injection for Numbness) Study

Overview

Postpartum pain can interfere with patient's ability to care for themselves, and their newborn, and untreated pain is associated with risk of greater opioid use, postpartum depression, and development of persistent pain. The research hypothesis of this study is that adding a locally injected analgesic, which will take effect once the epidural analgesia fades, may alleviate perineal pain and improve women's overall well-being and satisfaction. The objective of this study is to determine if prolonged analgesia and higher rate of maternal satisfaction are found when bupivacaine with epinephrine infiltration is used for perineal repair as compared to sham injection in patients with pre-existing effective epidural analgesia at time of perineal laceration repair.

Perineal lacerations, the disruption of the skin, mucosa and sometimes muscles that happen commonly during vaginal birth secondary to stretching of the introitus; are present in more than 75% of all vaginal deliveries. These lacerations can be classified based on the location and depth (layers injured). However, the classification of these lacerations does not correlate necessarily with postpartum pain. Severe lacerations, as those compromising the external or internal anal sphincter are less common and associated with more postpartum pain. It is common practice that only those lacerations causing bleeding, or distortion of normal pelvic anatomy are repaired. The repair of such lacerations at Montefiore Einstein is usually done using lidocaine for non-epiduralized patients; however, for patients with a functional epidural, no anesthetic agents are given locally to aid on long term pain control. The prevalence of perineal lacerations is more than 75% of all vaginal deliveries. The repair of such lacerations in the institution is usually done using lidocaine for non-epiduralized patients versus no local injection in patients with a pre-existing epidural analgesia. The prevalence of epidural analgesia use among women who underwent vaginal delivery in cross-sectional study of over 2 million deliveries in the United States was 71.1%. Once the analgesic effect of the epidural analgesia fades, the laceration may cause uncontrolled postpartum pain which can affect both the physical and mental recovery period, extend hospital stays, and increase the potential for serious adverse reactions with pain medications.