Ketamine Use in Pain Management – First Guidelines Published

Consensus guidelines for ketamine use in pain management have been developed jointly by the American Society of Regional Anesthesia and Pain Medicine, the American Academy of Pain Medicine, and the American Society of Anesthesiologists

Ketamine is a drug that is used for the initiation and maintenance of anesthesia during invasive or non-invasive procedures. It produces loss of consciousness and analgesia as well.

Ketamine is a potent drug and produces a temporary trance-like state and therefore has a great potential for abuse owing to its hallucinogenic, tranquilizing and dissociative effects.

Prolonged use can lead to tolerance and psychological addiction.

There is increasing evidence as indicated by the studies over the years that ketamine could have a role in pain management apart from being a potent anesthetic.

Ketamine is also increasingly being used in inpatient and outpatient settings to manage acute pain.

The first ever guidelines for use of ketamine in pain management have been recently published in journal Regional Anesthesia and Pain Management.

The guidelines suggestIntravenous [iv] ketamine for acute pain can be used in a variety of situations either alone or as complement to the opioids.

Another route, namely intranasal route has been included.

The aim of the guidelines is to provide a framework on the use of ketamine for acute pain.

Need for an Alternative to Opioid

Opioids are great pain relievers but there is a risk of addiction with prolonged use. There is an increased need to reduce the amount of opioids being consumed and the complications associated, including addiction.

The guidelines advise that subanesthetic ketamine infusions for patients undergoing painful surgery especially in opioid-dependent or opioid-tolerant patients.

The ketamine may be considered for opioid-dependent or opioid-tolerant patients with acute or chronic sickle cell pain.

In patients with sleep apnea, ketamine may be considered as an adjunct to decrease the need for opioids.

Dosages

For perioperative pain control

• Ketamine bolus doses should not exceed 0.35 mg/kg
• Infusions for acute pain generally do not exceed 1 mg/kg per hour in settings without intensive monitoring.
• The dosage can be altered in cases of prior ketamine exposure,

Where Not to Give Ketamine

Ketamine should be avoided in

• Poorly controlled cardiovascular disease
• Active psychosis,
• Pregnant women
• Severe liver disease
• Elevated intracranial pressure
• Elevated intraocular pressure
• Use with caution and monitoring in moderate liver disease
  • Liver function test results before and during infusions

Intranasal Ketamine and Its Use

Intranasal ketamine is beneficial for acute pain management. It provides effective analgesia, amnesia, and procedural sedation.

Intranasal ketamine can be considered in

• Difficult IV access
• Children undergoing procedures.

Oral Ketamine Use

Oral ketamine has not been found that effective but may provide short-term benefit in some individuals with acute pain.

Patient-controlled IV ketamine Analgesia

The studies suggest that there is only mild evidence for use of ketamine as sole analgesic for acute or periprocedural pain in patient controlled analgesia but there is moderate evidence of the benefit of the addition of ketamine to opioid-based IV patient-controlled analgesia.

More Research Needed

The authors have called ketamine a powerful and inexpensive tool for managing acute pain.

More research is suggested for increasing the scope of use of ketamine in

• Treatment of acute pain
• Possible prevention of chronic pain
• To determine the ideal dosing and treatment regimen
• To better understand the long-term risks

For complete text on the guidelines, follow the link in the references.

 References

Eric Schwenk, Eugene Viscusi, Asokumar Buvanendran, et al. Consensus Guidelines on the Use of Intravenous Ketamine Infusions for Acute Pain Management From the American Society of Regional Anesthesia and Pain Medicine, the American Academy of Pain Medicine, and the American Society of Anesthesiologists. Reg Anesth Pain Med. July 2018 – Volume 43 – Issue 5 – p 456–66.  doi: 10.1097/AAP.0000000000000806

Link