A comparative study between Ultrasound Guided Continuous Femoral Nerve Block combined with Obturator Nerve block or Sciatic Nerve Block or Both for analgesia after Total Knee Arthroplasty under General Anesthesia

Abstract

When a noxious stimulus produces tissue injury, chemical mediators are released and stimulate nociceptors which in turn generate nerve impulses. Uncontrolled postoperative pain poses an adverse outcome of restricted mobility, delayed resumption of pulmonary function, nausea with vomiting, increase in cardiac work, systemic vascular resistance and myocardial oxygen consumption through an increase in the catecholamine release in response to stress response. Knee surgeries are associated with moderate to severe postoperative pain, so these procedures are better to be done under regional anesthesia which reduces neuroendocrinal stress response, central sensitization of the nervous system and muscle spasms which occur as a response to painful stimulus. Recently, among these regional anesthetic techniques peripheral nerve blocks are gaining popularity because they reduce the possibility of complications and adverse effects associated with central blocks. Multiple nerve blocks provide more effective anesthesia and analgesia in total knee arthroplasty than femoral nerve block alone.