Chronic pain after cesarean section. Influence of anesthetic/surgical technique and postoperative analgesia

Brazil ranks second among countries with the highest rates of cesarean section in the world. Little is known about the future consequences of this procedure on maternal health. This study investigated the influence of anesthetic/surgical technique and postoperative analgesia on the onset of chronic pain after three months of cesarean section.

This is a prospective randomized study of 443 patients undergoing cesarean section (elective and emergency), with different doses of hyperbaric bupivacaine 0.5% and opioids in spinal anesthesia. Patients were alocated into five groups as follow: G1 received hyperbaric bupivacaine (8 mg), sufentanil (2.5 μg), and morphine (100 μg); G2 received hyperbaric bupivacaine (10 mg), sufentanil (2.5 μg), and morphine (100 μg); G3 received hyperbaric bupivacaine (12.5 mg) and morphine (100 μg); G4 received hyperbaric bupivacaine (15 mg) and morphine (100 μg); G5 received hyperbaric bupivacaine (12.5 mg) and morphine (100 μg), without perioperative anti-inflammatory. Pain at rest and in movement were evaluated in the immediate postoperative period. Phone contact was made after three months of surgery for identification of patients with chronic pain.

The incidence of chronic pain in the groups was G1=20%; G2=13%; G3=7.1%; G4=2.2%, and G5=20.3%. Patients who reported higher pain scores in the postoperative period had a higher incidence of chronic pain (p<0.05).

The incidence of chronic pain decreases with higher doses of local anesthetics and use of anti-inflammatory drugs. The higher pain scores in the postoperative period were associated with chronic pain development after three months of cesarean section.