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Non-Opioid Analgesics

Drug Dose Contraindication
Side Effect



C: renal failure, gi bleed, thrombic event
CABG, age >60, thrombocytopenia



S/E increased glucose levels

Dose dependent effect on pain and PONV



S/E: post-op sedation with higher doses

600 mg decreases PONV



S/E: angioedema, thrombocytopenia, rhabdomyolysis, increased pr interval

Faster absorption than Gabapentin



Do not need Versed at these doses

Prevents opioid tolerance & opioid induced hyperalgesia



C: Renal failure S/E: limitis ACh release, use caution in neuromuscular disease. Prolongs NMB

Labs not needed. Dose not correlated to analgesic effect

Nitrous Oxide


C: pul htn, B12 anemia, low O2 sat

50% ET=15mg morphine


2-5mcg/kg IV; 5-7mcg/kg PO; 0.2-0.5mcg/kg/hr

S/E: bradycardia, hypotension

Anxiolytic, prevent post-op shivering


1mcg/kg/10min 0.2-1mcg/kg/hr

S/E: bradycardia, hyper/hypotension, less severe than Clonidine


1G or 15mg/kg <50kg

C: liver failure/dysfunction

PO or IV



C: pediatrics, MAOI, linezolid, methylene blue


0.5-1mg/kg; 5-500mcg/kg/min

C: bradycardia, AV block


1.5mg/kg bolus; 2-3mg/kg/hr intra-op; 1.3mg/kg/hr post-op

C: AV block, seizures

1.5mg/kg/hr if concerned about metanbolism

Blue = Anti-inflammatory     Green = Glutamate    Red = Substance P    Orange = Miscellaneous

Protocol for Opioid Free Anesthesia for Spines

Pre-medicate in ASU with:

  • Acetaminophen 650-975 mg (repeat intraoperatively with rectal suppository at 6-8 hours or IV. Acetaminophen if available)
  • Gabapentin 600-1200mg
  • Celebrex 200-400mg (clear with surgeon)


  • Midazolam 1-2 mg
  • Dexmedetomidine 0.5-1 mg/kg over 10 minutes
  • Lidocaine 2 mg/kg
  • Ondansetron 4 mg
  • Dexamethasone 10 mg (please ensure that surgeon is okay with that)
  • Ketamine 0.5 mg/kg
  • Propofol 1 mg/kg


  • Ketamine 2-5 mcg/kg/min
  • Lidocaine 1.5-2 mg/kg/hr
  • Dexmedetomidine 0.15-0.3 mcg/kg/hr (If intra-op wakeup test likely, then low dose or eliminate infusion and then re-dose at the end)
  • Propofol 50-100 mcg/kg/min
  • Rocuronium 10-20 mg/hr
  • MgSO4 30-50 mg/kg
  • +/- Clonidine 2-5 mcg/kg earlier in the case (will help with lowering BP as often requested and longer acting analgesia than Dexmedetomidine)

This technique can be modified for essentially any general cases, and can be especially helpful for large abdominal cases (TAH/BSO, large hernias, bowel resections and lysis of adhesions), consider using regional (i.e. TAP blocks or similar) additionally for these large abdominal cases.

In patients with HIGH preoperative opioid tolerance consider adding opiates to the mix (remifentanil/sufentanil drips or front loading with Hydromorphone, Morphine, or Methadone) depending on length of surgery and opioid tolerance.

In patients who received pre-op Celecoxib, please keep in mind that an additional dose of Ketorolac at the end of surgery might be too much.

A few additional points to consider:

Ketamine can interfere with BIS/ Sedline monitoring. The machines will interpret the more “active” EEG as a patient, who is more awake and therefore one can get false high readings. Wake-up tests are not uncommon for large corrective spine surgeries. Consider not using Dexmedetomidine or using a lower dose to ensure prompt wake up if necessary. (We think it is Dex that keeps the patients asleep). 

Magnesium can interfere with neuro-monitoring, particularly MEP.  In large scoliosis correction surgeries, we see changes in evoked potentials quite often. While Magnesium infusion is still an option it might not be the best drug for these cases. It can be added to the anesthetic at the end of surgery once neuro-monitoring is complete to aid with post-operative pain control. As always close communication with the neurophysiologists is recommended.

If at all possible continue Ketamine infusion post-operatively to help with post-op pain treatment.