Effect of Intrathecally Administered Ketamine, Morphine, and Their Combination Added to Bupivacaine in Patients Undergoing Major Abdominal Cancer Surgery a Randomized, Double-Blind Study

Abstract

Adding intrathecal ketamine 0.1 mg/kg to morphine 0.3 mg in patients who underwent major abdominal cancer surgery reduced the total postoperative morphine consumption in comparison with either drug alone, with an overall good postoperative analgesia in all groups, with no side effects apart from sedation.

Continuous thoracic spinal anesthesia with local anesthetic plus midazolam and ketamine is superior to local anesthetic plus fentanyl in major abdominal surgery

“…Indeed, adverse effects of intratechal ketamine were reported in animal studies when doses of at least 0.7 mg/kg were applied and repeated for several days, and it was not clear if the neurotoxicity observed was related to preservatives contained in the solutions used or directly to the amount of ketamine used. Even if the dose applied in our study of 0.25 mg/kg is greater than that used in the cited study of 0.1 mg/kg [ 30 ], it is considerably inferior to that responsible for important adverse effects. Similarly, PONV might be directly related to the administration of intrathecal opioids [ 28 ].…”

“…Therefore, it can be helpful to develop a technique that allows sparing of the neuraxial opioid, replacing it with other adjuvants. This strategy was based on limited but encouraging evidences that midazolam and ketamine significantly improve the duration and quality of spinal anesthesia, reduce the onset time of sensory and motor block, provide a mild intraoperative sedative effect, ensure prolonged perioperative analgesia due to delayed recovery time of sensory block, and decrease the incidence of postoperative nausea and vomiting (PONV) without negative effects on perioperative hemodynamics, significant adverse effects, and neurotoxicity [ [29] , [30] , [31] ].…”

“…Likewise, the need for intraoperative sedation reached statistical significance, meaning that intravenous sedation drugs were administered to a significantly reduced number of patients in the LA + M + K group during surgery. This relationship between the type of spinal anesthesia and sedation is easy to explain because intrathecal midazolam and ketamine possess an intrinsic anxiolytic effect according to the literature [ [29] , [30] , [31] ]. This is another potential noteworthy benefit of this regimen because the elderly represents the group with the highest risk of serious adverse effects from systemic benzodiazepines, and the 2019 American Geriatrics Society’s updated Beers Criteria continue to list benzodiazepines and barbiturates as drugs to avoid in in patients more than 65 years of age with a strength of recommendation classified as strong in all ambulatory, acute, and institutionalized settings of care [ 33 ].…”

“…After analyzing the other complications, we noted an increasing trend of acute hypertension in the study group and of PONV in the control group, although it was not statistically significant. Acute hypertension might be related to the stimulant effect of ketamine on the orthosympathetic system even if low doses of intrathecal ketamine such those used in our series should not present systemic or neurologic toxicity according to literature [ 30 ]. Indeed, adverse effects of intratechal ketamine were reported in animal studies when doses of at least 0.7 mg/kg were applied and repeated for several days, and it was not clear if the neurotoxicity observed was related to preservatives contained in the solutions used or directly to the amount of ketamine used.…”

Paravertebral Block Versus Preemptive Ketamine Effect on Pain Intensity after Posterolateral Thoracotomies: A Randomized Controlled Trial

“…Its action is mediated via N-methyl-D-aspartate (NMDA)-receptors [10]. Many recent studies endorse the analgesic features of ketamine [11][12][13][14], but only a few trials directly compare ketamine with regional anesthesia techniques in patients undergoing thoracic surgery [15][16][17].…”