Efectividad del uso de ketamina perioperatoria en pacientes sometidos a cirugía de raquis en tratamiento crónico con opioides

Introduction: The number of patients receiving chronic opioids undergoing spinal surgery has increased lately. Elevate records in visual analog scale (VAS) and opioid consumption are higher in this group of patients. Material and methods: Following the recommendations of the American Pain Society (APS), a new intra and postoperative analgesic protocol based on the use of ketamine was designed in 2018. Intraoperatively, a bolus of 0.5 mg/kg of ketamine was administered, followed by a dose infusion of 0.2 mg/kg/h until the surgical wound was closed. During the first 48 postoperative hours, a patient-controlled analgesia pump (PCA) of morphine-ketamine was maintained along with a multimodal analgesia regimen with paracetamol and dexketoprofen. An effectiveness analysis comparing the new protocol (ketamine group) with the previous one (control group), based on the use of tramadol 100 mg / 6h or PCA morphine, was done. During the first 48 postoperative hours, NVS records, need of rescue analgesia, morphine bolus or continuous morphine infusion (control group) or ketamine morphine infusion (ketamine group) were analyzed. Results: The patients in the ketamine group had lower NVS records than those in the control group during the first two postoperative hours (p = 0.001) and lower morphine rescues needs on the second postoperative day (p = 0.003). The need for continuous morphine-ketamine perfusion was significantly lower than the need for continuous morphine perfusion on the control group (p = 0.011). Conclusion: The protocol based on the use of ketamine, managed to improve the control of postoperative pain and significantly reduce the consumption of opioids in the first 48 hours after the intervention.