Administration Of Low-dose Ketamine Research Articles

Efficacy of prophylactic use of hydrocortisone and low dose ketamine for prevention of shivering during spinal anesthesia

BackgroundSpinal anesthesia is commonly associated with shivering. The aim of this study was to compare the efficacy of i.v. hydrocortisone with i.v. low dose ketamine or placebo for prevention of shivering during spinal anesthesia.MethodIn this prospective, randomized, double-blind study, 90 female patients ASA I–II age 30–60 years old, undergoing posterior vaginal repair surgeries under spinal anesthesia with 3 ml heavy bupivacaine 0.5% (15 mg), patients were randomly allocated into one of three groups, (Group S, n = 30) (control) received saline, (Group K, n = 30) received ketamine 0.25 mg kg−1 or (Group H, n = 30) received hydrocortisone 2 mg kg−1, the drugs were given i.v. just after spinal anesthesia with recording of vital signs, and core temperature every 15 min intraoperative and every 10 min in recovery room. The incidence and intensity of shivering, number of patients received meperidine, sensory level, motor block grade, and side effects (hypotension, hypertension, tachycardia, nausea and vomiting, sedation and hallucinations) were also recorded.ResultsIncidence of shivering were significantly reduced in k and H groups being 20% and 23.3% respectively compared to S group (p < 0.05). Patients received meperidine to control shivering were significantly low in Groups K and H compared to group S (p < 0.05), with no difference between Groups K and H.ConclusionsThe prophylactic administration of low dose ketamine (0.25 mg kg−1) and hydrocortisone (2 mg kg−1) were comparable in reducing the incidence of shivering and both had significant antishivering effect compared to placebo, in female patients under spinal anesthesia for posterior vaginal repair surgeries.

Analgesic Effect of Subanesthetic Intravenous Ketamine in Refractory Neuropathic Pain: A Case Report

A 59-year-old male patient with progressive neuropathic pain secondary to chronic idiopathic axonal polyneuropathy responded poorly to conventional therapies including gabapentin, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors and opioids. Following continuous intravenous administration of low dose ketamine, an N-methyl-D-aspartic acid receptor antagonist, 20 mg/h for 5 days, almost complete pain relief was obtained without significant side effects. The analgesic effect lasted 10-12 weeks and the ketamine infusion was repeated, with this pattern being maintained for 3.5 years. This supports the growing body of evidence that ketamine may be useful in the management of refractory chronic neuropathic pain. We discuss chronic idiopathic axonal polyneuropathy, neuropathic pain mechanisms, and the use of ketamine in this report.

Evaluation of a combination of low-dose ketamine and low-dose midazolam in terminal dyspnea-attenuation of "double-effect"

Aim: Of all symptoms in palliative medicine those concerning respiration are most excruciating and difficult to treat. Reticence about the use of morphine for palliation of dyspnea is common, especially in nonmalignant diseases, as there is a fear of causing respiratory depression, particularly where Chronic Obstructive Pulmonary Disease (COPD) exists. This factor is also compounded by the lack of availability of morphine in parts of developing countries. Ketamine has excellent anesthetic and analgesic effects in addition to being easily available. It produces bronchodilatation and does not produce respiratory or cardiovascular depression. The author seeks to evaluate the role of low-dose (0.2 mg/kg) ketamine and midazolam (0.02 mg/kg) in the attenuation of terminal dyspnea. Methods: Sixteen patients with terminal dyspnea, admitted to the Critical Care Unit (CCU) with cancer and other noncancer diagnoses were recruited. The subjective component of dyspnea was assessed using the Graphic Rating Scale (GRS), which has values from 0 - 10, 10 being maximum dyspnea. Each patient received a low-dose of ketamine and midazolam for relief of dyspnea. All the patients received low-flow (2 L/min.) oxygen therapy via nasal cannula. Immediately after admission, all the patients were reassured and nursed in a decubitus position of their choice. The GRS was recorded at the point of admission, 10 minutes after starting oxygen therapy, and ten minutes after administration of low-dose ketamine and midazolam. Hemodynamic parameters were also recorded at these three points. Result: All the patients who enrolled in our study had significant dyspnea at admission, as was evident from the GRS scores of 8.250 (SD 0.91), respiratory rate of 28.56 (SD 5.0), mean arterial blood pressure (MABP) of 102.7 (SD 14.63), pulse rate of 115.62 (SD 23.3), and SpO2 of 92.43 (SD 2.38). All the patients benefited from the combination of ketamine and midazolam, as evidenced by the statistically significant ( P < 0.01) improvement in all monitored parameters. Conclusion: The author concludes that a combination of low-dose ketamine and midazolam can be safely used in the palliation of terminal dyspnea, with excellent results. The duration of action of this combination in providing symptomatic relief is however short-lived, being 36.7 minutes on an average (SD 5.23), thus necessitating intermittent IV top-ups. No adverse reports were obtained in the study.

Perioperative Uses of Low-Dose Ketamine for Pain Management

The purpose of this article is to explore the most current literature regarding perioperative pain management uses of low-dose ketamine. Research has demonstrated significant reductions in postoperative pain scores as well as opioid consumption with low-dose ketamine administration without side effects associated with its induction doses. The availability of S(+)-ketamine with double the analgesic potency of ketamine will create even more reason for its use.

Preoperative epidural administration of low-dose ketamine may provide more effective analgesia

Preoperative epidural administration of low-dose ketamine may provide more effective analgesia

Repeated administration of low dose ketamine for the treatment of monoarthritic pain in the rat

The aim of the present study was to observe the effect of repeated subcutaneous (sc) injections of low doses of ketamine for the treatment of acute inflammatory pain in a complete Freund's adjuvant-induced monoarthritic pain model in rats. The results show: (1) sc injection of ketamine at a dose of 2 mg·kg −1 or 10 mg·kg −1 produced significant analgesia ( P<0.01) in arthritic rats starting from the 2nd week and 3rd week, respectively. (2) Repeated administration of ketamine produced a significant reduction of the circumference of the arthritic ankle ( P<0.05 and P<0.01 with different doses). (3) The body weight of the rats was not affected by continuous administration of ketamine for 4 weeks. No abnormal locomotor behavior was observed (It was concerned but not systemically evaluated in this study). The results suggest that repeated sc injection of ketamine for 4 weeks significantly reduce inflammatory pain in monoarthritis without notable aversive side effects.