Ketorolac in Anesthesia

Ketorolac (Toradol) is a nonsteroidal anti-inflammatory analgesic used as an adjunct for general anesthesia. Specifically, ketorolac is especially effective at reducing pain related to inflammation and in the management of mild to moderate pain.

Common doses for ketorolac in anesthesia range from 15 to 30 mg. This said, however, recent studies have shown that therapeutic ceiling is achieved with only 10 mg. Higher doses tend to contribute to a higher incidence of side effects and may extend the duration of effect beyond what is optimal, so it is important to use the minimal effective dose for a patient. In anesthetic contexts, ketorolac is usually administered as an adjuvant to traditional opioids.

Ketorolac is advantageous as it works synergistically with opioids, with very little incidence of nausea and vomiting and no respiratory depression. It is thus ideal for use in cases in which it is important to avoid or minimize using opioids, such as in the context of laparoscopic and pediatric dental cases.

Interestingly, a recent prospective randomized controlled trial also found that ketorolac tromethamine can help suppress coughing. Coughing can increase discomfort during recovery and cause extra movements, so this finding has sparked interest. Study data demonstrated that intravenous ketorolac tromethamine pretreatment may significantly reduce the incidence of sufentanil-induced cough during general anesthesia induction and may also significantly reduce postoperative incision pain and restlessness during a patient’s recovery period.

A recent meta-analysis of randomized trials further found that a perioperative single dose ketorolac was effective for managing postoperative pain. Indeed, a single dose of ketorolac reduced post-operative pain as well as post-operative nausea and vomiting. Specifically, a dose of 60 mg ketorolac offered significant benefits, but a 30 mg dose did not demonstrate significant benefits. Regarding implications for practice, the authors recommended that anesthesia providers reconsider the routine use of 30 mg ketorolac.

There is still a need for large, randomized trials as well as for trials focusing lower doses. Future studies that directly compare various routes of administration will also help clarify the optimal uses of ketorolac in anesthesia.

Furthermore, it is important to note that ketorolac may cause a certain degree of ototoxicity by direct and indirect mechanisms. Reports are rare, but toxicity, should it occur, is often irreversible. In addition, ketorolac has an additive ototoxic effect when used in combination with other ototoxic drugs, such as aminoglycosides, vancomycin, erythromycin, loop diuretics, antineoplastic agents, salicylates, or other nonsteroidal anti-inflammatory drugs.

Ketorolac should not be used in patients with coagulopathies, renal failure, active peptic ulcer disease, a history of asthma, gastrointestinal bleeding, or a high risk for bleeding. In addition, it should not be administered to parturients that are past their first trimester since it can cause the fetal ductus arteriosus to close. Finally, it should be avoided in pediatric patients undergoing a tonsillectomy since it can increase postoperative bleeding complications; acetaminophen or tramadol should be used instead.

References

1. Schoneboom, B. A. Ketorolac tromethamine: A nonsteroidal anti-inflammatory analgesic used as an adjunct for general anesthesia. J. Am. Assoc. Nurse Anesth. (1992).

2. Ketorolac (Toradol) – Master Anesthesia. Available at: https://masteranesthesia.com/ketorolac-toradol/. (Accessed: 28th September 2023)

3. Tian, Z. et al. Ketorolac tromethamine pretreatment suppresses sufentanil-induced cough during general anesthesia induction: A prospective randomized controlled trial. BMC Anesthesiol. (2020). doi:10.1186/s12871-020-01124-5

4. De Oliveira, G. S., Agarwal, D. & Benzon, H. T. Perioperative single dose ketorolac to prevent postoperative pain: a meta-analysis of randomized trials. Anesth. Analg. 114, 424–433 (2012). doi: 10.1213/ANE.0b013e3182334d68.