Perioperative Pain Management for Thyroidectomy

Ketamine Administration

The American Society of Anesthesiologists recommends administering ketamine after anesthesia induction to prevent psychodysleptic side effects, with a bolus dose of 0.5 mg/kg (maximum) and a continuous infusion at 0.125-0.25 mg/kg/h throughout the procedure, stopping 30 minutes before the end of surgery 1, 2, 3
Ketamine is the first-line anti-hyperalgesic agent for patients on remifentanil-based anesthesia, reducing 24-hour morphine consumption by approximately 15mg and decreasing acute pain intensity 1, 2
The regimen reduces chronic postoperative pain incidence by 30% at 3 months, with moderate evidence quality 1

The American Pain Society recommends not administering morphine intraoperatively, instead using remifentanil infusion for intraoperative analgesia, and initiating morphine in the PACU with an initial dose of 0.025-0.1 mg/kg IV, titrated to effect based on pain scores 1, 4, 5
Morphine remains the reference opioid for postoperative pain management, with administration in small increments of 2-3mg IV every 5-10 minutes until pain is controlled (VAS <4/10) 1, 5

The American Society of Anesthesiologists recommends using dexamethasone 8mg IV at induction to reduce postoperative pain and PONV, and IV lidocaine as an adjunct to reduce morphine requirements and improve recovery 1, 2, 3
NSAIDs, if not contraindicated, reduce opioid consumption significantly, and local wound infiltration with bupivacaine 0.5% reduces opioid requirements 6

The American Society of Anesthesiologists recommends continuous pulse oximetry until the patient is mobile postoperatively, observing for apnea/hypopnea episodes while unstimulated before PACU discharge, and ensuring respiratory rate is normal with no hypopnea for at least 1 hour before ward transfer 4
Approximately 10% of patients receiving higher opioid doses develop persistent postoperative respiratory depression, according to the World Health Organization 7, 8