0.2 mg/kg of methadone (based on ideal body weight, up to a maximal dose of 20 mg)250 mg of ketamine was added to the dextrose 5% in water bag (total volume 500 ml). 500 ml bags were connected to a pump that was programed to deliver an infusion of ketamine dosed at ideal body weight (or an equal volume of dextrose 5% in water) at a rate of 0.3 mg · kg−1 · h−1 from induction of anesthesia until surgical closure, at which time the infusion was decreased to 0.1 mg · kg−1 · h−1. The infusion was maintained at a rate of 0.1 mg · kg−1 · h−1 in the postanesthesia care unit (PACU) and for the next 48 postoperative hours. Dosing of ketamine was based on recommendations in the literature17,18 and from clinical experience at our institution.
Consider continuing current or decreased buprenorphine dose
Consider non-opioid therapies: ketamine, gabapentin, acetaminophen, regional, lidocaine infusions, etc.
Team management with pain physician, surgeon, anesthesiologist, nurses, and patient
When mild to moderate acute pain is anticipated for a short period of time (e.g. dental extraction), consider treating the pain with buprenorphine and nonopioid analgesics such as NSAIDs. The total daily dose of buprenorphine can be increased (to a maximum of 32 mg sublingual/day); it should be given in divided doses every 6-8 hours.
When opioid analgesic therapy is expected to be required for a short period of time for moderate to severe pain, federal guidelines recommend holding the buprenorphine and starting short acting opioid agonists. While the buprenorphine’s effects diminish (20-60 hours), the patient should be monitored carefully for the first several days as higher opioid doses may be needed to compete with the presence of buprenorphine on mu-opioid receptors. Before restarting buprenorphine, the patient should be opioid-free for 12-24 hours, otherwise the reinitiation of buprenorphine could precipitate withdrawal. This process should be overseen by an approved buprenorphine provider.
Another option is to continue buprenorphine and use short-acting opioid agonists at high enough doses to overcome buprenorphine’s partial agonism. One retrospective chart review found decreased opioid requirements in patients who were continued on buprenorphine during and after surgery. Opioids that have a higher intrinsic activity at the mu-opioid receptor, including morphine, fentanyl, or hydromorphone, are all options, while opioids with less efficacy such as hydrocodone or codeine should be avoided.
If a patient is expected to have an ongoing, long-term need for opioid analgesia (e.g. cancer progression), consider replacing buprenorphine with methadone. Then, other as needed ‘full’ mu-opioid receptor agonists can be added for breakthrough pain without problems related to use of a partial opioid agonist.
Nov 2021: (includes Oct ASA annual mtg recommendations)
Buprenorphine is a good analgesic. Some patients prefer it to other opioids, even post-op. It is not recommended to stop buprenorphine, which can lead to relapse in 50% of patients. There is a significant increase in mortality in patients in the first month after buprenorphine is stopped.
Regional Anesthesia & Pain Medicine journal recommends no weaning.
Mass General considers high dose to be more than 16 mg daily.
Different approach suggested in Anesthesiology 2016 paper.
If patient is on 32 mg, only 5% of mu receptors are left for anesthesiologist to work with. If patient is on 16 mg, 20% of mu receptors are available. If patient is on 8-10-12 mg, 50% of mu receptors are available, which is why this is considered optimal by some. Need to overcome receptors with opioids that are high potency, high affinity and titratable, fentanyl and hydromorphone.
With an opioid crisis at its peak, physicians need to be more cognizant of the various pain modalities available to patients. Gabapentinoids are one of the many non-opioid options to help with acute and chronic pain.
Methadone for perioperative pain #methadone #pain #ERAS
There’s a lot of great data that methadone use decreases postoperative narcotics use in cardiac surgery patients, and I believe it would really be a beneficial drug in an ERAS pathway for early extubation, decreased LOS in ICU and hospital, and better patient satisfaction. Please see the articles below/attached for references.
OVERALL: A variety of doses have been used in clinical trials, ranging from 0.1 to 0.3 mg/kg, with the majority of studies using a dose of either 0.2 mg/kg or a fixed dose of 20 mg.
Cardiac: Ketamine current pt weight (non-adjusted) 0.2mg/kg/hr start after induction (after lines placed) + 0.35 mg/kg 5-10 minutes prior to incison. Change from 0.2mg/kg/hr to 0.1mg/kg/hr when rewarming. Infusion off when driving sternal wires. Methadone currently not available.
Non-cardiac (cases 2+ hours duration) Ketamine: 0.3mg/kg (non-adjusted, current weight) at induction. Methadone currently not available.
Outpatient: ketamine not currently available for use.
July 2020
Cardiac: Ketamine IBW 0.3mg/kg total: 0.2mg/kg prior to incision + 0.1mg/kg when separate from CPB
0.2 mg/kg of methadone (based on ideal body weight, up to a maximal dose of 20 mg)
250 mg of ketamine was added to the dextrose 5% in water bag (total volume 500 ml). 500 ml bags were connected to a pump that was programed to deliver an infusion of ketamine dosed at ideal body weight (or an equal volume of dextrose 5% in water) at a rate of 0.3 mg · kg−1 · h−1 from induction of anesthesia until surgical closure, at which time the infusion was decreased to 0.1 mg · kg−1 · h−1. The infusion was maintained at a rate of 0.1 mg · kg−1 · h−1 in the postanesthesia care unit (PACU) and for the next 48 postoperative hours. Dosing of ketamine was based on recommendations in the literature17,18 and from clinical experience at our institution.
I’m always looking for ways to improve myself. Lately, I’m looking at various clinical elements of my practice and select certain endpoints that will better my practice of medicine.
This time, I’ve focused on cutting back on opioids intraoperatively for pain. I’m looking specifically at ketamine, an old drug with multiple benefits (and some downsides). Not only does ketamine help with intraoperative pain, but it also helps with postoperative pain. I’d like to incorporate some type of ERAS model for all of my patients and surgeries.
Ketamine: (different doses I’ve seen in the literature below)
• Induction: 0.2-0.5 mg/kg
• Infusion: 0.1mg/kg/hr before incision
◦ 2mcg/kg/hr x 24hr (spine)
◦ 0.1-0.15mg/kg/hr x 24-72hrs (UW)
◦ 2mcg/kg/min
◦ 2-8mcg/kg/min
Overall, moderate evidence supports use of subanesthetic IV ketamine bolus doses (up to 0.35 mg/kg) and infusions (up to 1 mg/kg per hour) as adjuncts to opioids for perioperative analgesia (grade B recommendation, moder- ate level of certainty).
From Regional Anesthesia and Pain Medicine • Volume 43, Number 5, July 2018
What I’m using nowadays:
Oct 2017:
Cardiac open hearts: induction bolus=0.5mg/kg; infusion=0.1mg/kg/hr and stopping when last stitch placed. Patients seem to require less postoperative narcotics. Looking at time to extubation to see if this is improved. Time to extubation seems the same as my prior non-ketamine patients because RT and RNs follow a weaning protocol. Patients are more comfortable and require less pain medication.
Dec 2018:
Cardiac open hearts: induction bolus = 0.5 mg/kg + another 0.5 mg/kg bolus when re-warming.
July 2020:
Cardiac open hearts: induction infusion 0.3mg/kg/hr + 0.5mg/kg right before incision. 0.2mg/kg/hr when commence CPB. 0.1mg/kg/hr when re-warming. Stop infusion when driving wires.
Main OR: induction 0.35mg/kg + 0.2mg/kg/hr or 3mcg/kg/min = extubate patient in OR. Stop infusion when closing.
Cardiac open hearts: induction infusion 0.2mg/kg/hr + 0.35mg/kg right before incision. 0.1mg/kg/hr when re-warming. Stop infusion when driving wires.
Main OR: induction 0.35mg/kg + 0.1mg/kg/hr = extubate patient in OR. Stop infusion when starting to close. If fast closure, consider stopping infusion 30min to 1 hour prior to end of case.
March 2021:
Cardiac: 0.2mg/kg/hr after induction and lines placed + 0.35mg/kg 5-10 minutes before incision. 0.1 mg/kg/hr when re-warming. Stop infusion when placing sternal wires.
Non-cardiac (2+ hr duration case): 0.3mg/kg at induction.
Question 1: Which patients and acute pain conditions should be considered for ketamine treatment? Conclusion: For patients undergoing painful surgery, subanesthetic ketamine infusions should be considered. Ketamine also may be warranted for opioid-dependent or opioid-tolerant patients undergoing surgery, or with acute or chronic sickle cell pain. For patients with sleep apnea, ketamine may be appropriate as an adjunct to limit opioid use.
Question 2: What dose range is considered subanesthetic, and does the evidence support dosing in this range for acute pain? Conclusion: Ketamine bolus doses should not exceed 0.35 mg/kg, whereas infusions for acute pain generally should not exceed 1 mg/kg per hour in settings lacking intensive monitoring. However, dosing outside this range may be indicated because of an individual patient’s pharmacokinetic and pharmacodynamic factors and other considerations, such as prior ketamine exposure. However, ketamine’s adverse effects prevent some patients from tolerating higher doses for acute pain; therefore, unlike for chronic pain management, lower doses in the range of 0.1 to 0.5 mg/kg per hour may be necessary to achieve an acceptable balance between analgesia and adverse events.
Question 3: What is the evidence to support ketamine infusions as an adjunct to opioids and other analgesic therapies for perioperative analgesia? Conclusion: There is moderate evidence to support using subanesthetic IV ketamine bolus doses up to 0.35 mg/kg and infusions up to 1 mg/kg per hour as adjuncts to opioids for perioperative analgesia.
Question 4: What are the contraindications to ketamine infusions in the setting of acute pain management, and do they differ from chronic pain settings? Conclusion: Patients with poorly controlled cardiovascular disease or who are pregnant or have active psychosis should avoid ketamine. Similarly, for hepatic dysfunction, patients with severe disease, such as cirrhosis, should not take the medicine; however, ketamine can be given with caution for moderate disease by monitoring liver function tests before infusion and during infusions in surveillance of elevations. On the other hand, ketamine should not be given to patients with elevated intracranial pressure or elevated intraocular pressure.
Question 5: What is the evidence to support nonparenteral ketamine for acute pain management? Conclusion: Intranasal ketamine is beneficial for acute pain management by achieving effective analgesia and amnesia/procedural sedation. Patients for whom IV access is difficult and in children undergoing procedures are likely candidates. But for oral ketamine, the evidence is less convincing, although anecdotal reports suggest this route may provide short-term advantages in some patients with acute pain.
Question 6: Does any evidence support IV ketamine patient-controlled analgesia (PCA) for acute pain? Conclusion: The evidence is limited to support IV ketamine PCA as the sole analgesic for acute or periprocedural pain. There is moderate evidence, however, to support the addition of ketamine to an opioid-based IV PCA regimen for acute and perioperative pain therapy.
The guidelines were jointly developed by the American Society of Regional Anesthesia and Pain Medicine (ASRA), the American Academy of Pain Medicine and the American Society of Anesthesiologists.
Methadone: 0.2 mg/kg of methadone (based on ideal body weight, up to a maximal dose of 20 mg)
Ketamine: 250 mg of ketamine was added to the dextrose 5% in water bag (total volume 500 ml). 500 ml bags were connected to a pump that was programed to deliver an infusion of ketamine dosed at ideal body weight (or an equal volume of dextrose 5% in water) at a rate of 0.3 mg · kg−1 · h−1 from induction of anesthesia until surgical closure, at which time the infusion was decreased to 0.1 mg · kg−1 · h−1. The infusion was maintained at a rate of 0.1 mg · kg−1 · h−1 in the postanesthesia care unit (PACU) and for the next 48 postoperative hours. Dosing of ketamine was based on recommendations in the literature and from clinical experience at our institution.
Sleepy Time 