The effects of a single dose preemptive pregabalin on acute and chronic pain after inguinal hernia repair with mesh under spinal anesthesia

Postoperative pain is an acute pain, accompanied by the inflammatory process manifested due to the surgical trauma and progressively decreasing with ongoing tissue healing. A successful postoperative analgesia is well known to prevent many adverse effects of pain such as inability to breathe comfortably, increased workload of cardiovascular system, development of thromboembolic events due to delayed mobilization, increased stress response due to the activation of neuroendocrine and sympathetic nervous systems. In experimental studies, it has been shown that implementation of analgesia prior to surgical trauma might have reduced the posttraumatic sensitivity of the spinal cord and secondary hyperalgesia. Since peripheral hypersensitivity and central nervous system hyperexcitability might have developed if analgesic treatment is initiated after the painful stimulus, difficulties may be encountered in postoperative pain management in such cases. Pregabalin is a structural gamma-aminobutyric acid (GABA) analog. Its mechanism of action is not fully understood. Pregabalin is suggested to modulate the presynaptic release of excitatory neurotransmitters by binding to the a2-d protein subunit of voltage-sensitive calcium channels in the central nervous system. Pregabalin reduces the release of numerous neurotransmitters, including glutamate, noradrenaline, substance P, and calcitonin gene-related peptide. Conducted studies have shown that pregabalin might have a role in postoperative pain management. In many countries, inguinal hernia repair is the most frequently performed operation in general surgery. Each year, approximately 20.000.000 inguinal hernia repairs are made worldwide. Meshes, which are used in hernia repair, may lead to both acute and chronic pain development by increasing the inflammatory response. The incidence of postoperative chronic pain is estimated to be between 6 to 54%. The primary aim of this study was to investigate the effects of a single dose preemptive pregabalin on the duration of postoperative analgesia and opioid consumption in patients who had undergone inguinal hernia repair with mesh under spinal anesthesia. Our secondary aim was to determine the effect of pregabalin on chronic pain.