Protective Analgesia in Caesarean Section Using Intravenous Paracetamol: A Prospective Randomised Controlled Trial

Cesarean section (CS) is one of most common surgical procedure in women. Parturients undergoing CS, experience severe to moderate postoperative pain. Pain after CS may impair the ability of mother to care and feed her child, early ambulation, and discharge. About 12.3% of parturients experience pain scores enough to affect infant care up to 6 months after CS.

All of perioperative stress effects, before delivery of the baby, such as, skin incision, need various approaches of treatment, which may include systemic and neuraxial analgesia.

Surgical trauma causes immediate changes in both peripheral and central nervous systems, leading to augmentation of pain perception in the final destination - the cerebral cortex. The surgical incision induces secretion of cyclooxygenase-2 (COX-2), which increases the production of prostaglandins (PGs), and which in turn excites peripheral nociceptors. These special pain fibers not only transmit the pain signal to the central nervous system, but also amplify tissue sensitivity to the surgical trauma, giving rise to the phenomenon known as "local hyperalgesia".

Improper pain control during the perioperative period leads to complications, which may affect the outcome of CS. Pain relief is very important to the patient as the pain causes discomfort which affects hemodynamic intraoperative and increases the risk of postoperative complications as atelectasis, ineffective, coughing and inadequate ventilation. Adequate pain control is essential not only intraoperatively, but also in immediate postoperative period to cover long time period postoperatively. The major role of intra- or post-operative management of pain is to reduce the dose of medication and to lessen side-effects, while providing adequate analgesia. This role may best be accomplished with multimodal protective analgesia or preemptive analgesia. Protective multimodal analgesia term is described as any intraoperative analgesic agents able to control pain-induced sensitization of the central nervous system. Preemptive analgesia had been defined as an antinociceptive treatment, starts before surgery that to prevent establishment of altered central afferent input from injuries and its goal is to decrease pain by timing the analgesic's peak pharmacodynamic effect with anticipated onset of pain or peak pain response.

Protective analgesia is distinguished from pre-emptive analgesia in that it focuses less on the treatment and on the relatively timing and the anesthetic intervention but rather more on the mechanisms of action. Protective analgesia aims to decrease the impact of the nociceptive barrage associated with noxious pre-operative, intra-operative, and/or post-operative events/stimuli.