Authors: Enrico M. Camporesi, M.D. et al
Anesthesia Research Institute & University of South Florida, Tampa, Florida, United States
Introduction: Opioids produce many undesirable side effects such as respiratory depression, sedation, nausea/vomiting, constipation, and ileus. Short-acting opioid used during anesthesia may lead to acute opioid-induced tolerance and hyperalgesia . Furthermore, opioid addiction and overdosing are recognized as national problems. Most overdose deaths result from access to prescription opioids . Multimodal opioid-sparing analgesia has become an alternative to managing post-surgical pain in the last two decades . One of the anesthesiologists in our practice (DS) provided anesthesia services to 19 surgeons for 1,009 consecutive patients without the use of opioids for a variety of procedures.
Materials & Methods: We were granted IRB-approval from the University of South Florida’s IRB to retrospectively review surgical cases of patients with a single anesthesiologist at an outpatient surgery center. Surgical procedures included direct laryngoscopy, complex facial plastics, skin lesions, middle ear procedure, nasal/sinus procedures, and tonsillectomy and adenoidectomy
Opioid-Free Intraoperative Anesthesia Protocol: All adult patients received 1000mg of P.O. acetaminophen and pediatric patients receive 10-15mg/kg per rectum. If patients had obstructive sleep apnea, they received IV acetaminophen. All patients received magnesium 60mg/kg while patients over the age of 65 or having kidney disease received 30mg/kg. Ketamine (0.3mg/kg) and lidocaine (1.5mg/kg) was also given. Adult patients received 30mg Ketorolac (15mg if the patient is over 65 years of age) if the surgeon allowed it. Middle ear surgery patients received gabapentin 300mg P.O. All patients received Deacadron 10mg (peds 0.1mg/kg) and Zofran 4mg. All patients received supplemental Sevoflurane.
PACU Management: Patients were given oral hydrocodone or oxycodone for complaints of pain in the PACU and intravenous lidocaine/magnesium for complaints of intractable, unremitting pain in the PACU. If patients complained of nausea they were given 4mg Zofran. Patients received Phenergan if nausea persisted or vomiting ensued.
Statistical analysis involved logarithmic regressions between different procedural groups.
Results: Patients and surgeons declared satisfaction with this anesthesia protocol and post-operative pain management was well-tolerated. Only 36% of patients requested oral opioid medications in the PACU despite having received opioid-free anesthesia, with certain procedures such as complex facial plastics and nasal/sinus surgeries with longer case lengths requiring notably more pain medications than other surgical procedures. Patients in these two procedural groups also required more nausea medication (Table).
Discussion: The study shows that a general anesthetic can be provided safely without opioids, suggesting that multimodal analgesics are acting preemptively. Future prospective studies can elucidate which medications utilized during the OFA regimen are essential. Patients can also be monitored post-operatively to understand opioid needs for at-home pain. Our surgeons agreed to prescribe on average only 15 PO opioid tablets post-operatively for each patient, in lieu of the usual 50, thus decreasing unused pills leftover for possible diversion.
Conclusion: In conclusion, safe anesthesia for multiple procedures varying in duration from an hour to several hours while using minimal opioids is possible.
References: Angst, C. Anesthesiology 2006; 104:570-87  Rudd et al. CDC MMWR 2016; 64(50);1378-82  Kehlet, D. Anesth Analg 1993; 77:1048-1056