Small Doses Of Ketamine Research Articles

Combined Spinal-Epidural (CSE) technique plus ketamine in research laparotomies with vertical incision: Case report

The combined spinal-epidural (CSE) technique, a comparatively new anesthetic choice, includes an initial subarachnoid injection followed by epidural catheter placement and subsequent administration of epidural medications. Clinical studies have demonstrated that the CSE technique provides excellent surgical conditions as quickly as with single-shot subarachnoid block conditions that are better than with epidural block alone. A 72-year-old man with pelvic tumor undergoing laparotomy surgery underwent combined regional anesthesia (Th12 - O1) plus small doses of Ketamine via intravenus infusion. The combined spinal-epidural technique along with intravenous Ketamine offers a better analgesic and hemodynamic result.

Effect of small dose ketamine on morphine requirement after intestinal surgery: A randomized controlled trial

ABSTRACT Background: N-methyl-D-aspartate (NMDA) receptors are thought to be for pain memory, and blocking them can help to reduce pain. We aimed to assess the preventive effects of small doses of ketamine administered prior to the skin incision in abdominal surgery, to assess analgesic efficacy and intra-operative and post-operative side effects. Methods: 60 adult patients with ASA I and II who were scheduled for abdominal surgery were randomly divided into two groups in a prospective, double-blind study. Before the skin incision, group K received 1 mg/kg ketamine intravenously, followed by a 0.12 mg/kg/h ketamine infusion till the skin was closed. Instead of ketamine, group C received normal saline. After extubation, both groups received morphine 5 mg IV. The visual analogue scale (VAS) was used to measure analgesic effectiveness at rest and after exercise, as well as the duration to the first analgesic and morphine intake in 24 h, and analyze changes in serum CRP and IL6 levels as indicators of its impact. Also, side effects of opioid or ketamine have been recorded. Results: Within 24 h, patients in the ketamine group had a significantly lower VAS score, a longer time to the first analgesic (326.3 ± 49.5 minutes), and lower morphine consumption (6.9 ± 2.91 mg). Also, postoperative interleukin 6 and CRP showed significant difference between the two groups (p ≤ 0.05). In group K, no side effects were detectable. Conclusion: Ketamine may be a promising drug in low doses that can limit and even prevent worsened inflammation. It also resulted in decreased postoperative opioid use, decreased pain rating, earlier retains of bowel motility, and decreased incidence of side effects.

TO EVALUATE SAFETY AND EFFECTIVENESS OF KETAMINE-PROPOFOL COMBINATION AND PROPOFOL ALONE IN DIAGNOSTIC RADIOLOGICAL PROCEDURES (MRI) IN PEDIATRIC PATIENTS.

Introduction: There is a growing need for magnetic resonance imaging (MRI) in children for accurate diagnosis and appropriate medical treatment. In recent times, small doses of ketamine have been used along with propofol for pediatric MRI sedation. Aims and objectives: to evaluate safety and effectiveness of Ketamine-propofol combination and propofol alone in diagnostic radiological procedures (MRI) in pediatric patients. Materials and methods: The present prospective randomized double blinded study was undertaken at Government General Hospital, Tirupati. Pediatric patients aged between 2 to 12 years of both sex, belonging to ASA grade I & II and posted for elective MRI Brain scan were included in the study. Results: KP group had significantly more reactions than P group. Recovery time (time taken to achieve modified aldrete recovery score of 9-10) was 37.33±2.88 min and 19.6±2.67 min in Ketofol group and propofol group respectively. Conclusion: Ketofol is an attractive combination for procedural sedation.

A game changer for antidepressants

When it comes to treating depression, Gerard Sanacora thinks ketamine is a game changer. A textbook changer, really. To illustrate his point during lectures, the Yale University neuroscientist likes to include a slide showing an excerpt from a 20-year-old psychiatry textbook. The book “has this whole section about how it’s well known and accepted that recovery from depression takes weeks, if not months, through treatment” with medication, Sanacora says. In contrast, studies run in the past 2 decades have demonstrated that small doses of ketamine can relieve depression symptoms in hours or days. The drug, originally used in humans as an anesthetic starting in the Vietnam War, not only acts fast but also works in people who don’t respond to other antidepressants. About one-third of people with depression today have treatment-resistant depression (TRD). Ketamine “has changed the expectations in the field,” Sanacora says. In March 2019, the US Food and

Effect of small-dose ketamine in the prevention of pain on propofol injection: A prospective randomized controlled study

Background: Propofol is a commonly used intravenous anesthetic agent that produces pain when used for induction. In this study, small doses of ketamine are being used in comparison with lignocaine and placebo for alleviating pain on propofol injection. Aims and Objectives: The aim is to assess the effect of ketamine to prevent the pain on injection of propofol and to establish an optimal dose for this purpose. Materials and Methods: We conducted a prospective randomized double-blinded study (placebo controlled) in 160 patients belonging to the American Society of Anaesthesiologists grade 1 and 2 who were posted for elective surgeries to be done under general anesthesia. They were allocated randomly into five groups. Patients were administered normal saline (NS) (Group NS), lignocaine 1.5 mg/kg (Group lignocaine), ketamine 0.1 mg/kg (Group KT1), ketamine 0.3 mg/kg (Group KT2), and ketamine 0.5 mg/kg (Group KT3) just before injection of 1% propofol in a dose of 2.5 mg/kg. Pain scores of patients were assessed at intervals of 10 s by an anesthesiologist who was blinded to the test drug. Efficacy of the pretreatment drug was assessed based on pain score and the occurrence of pain. Results: The occurrence and intensity of pain were significantly higher in the placebo group (Group NS) compared to other study groups. The occurrence of pain and pain scores were lower in the KT2 and KT3 groups compared with the KT1 and lignocaine groups. Conclusion: This study concluded that ketamine administration in a dose of 0.3 mg/kg before propofol injection is beneficial and safe in preventing pain caused by injection of propofol.

Postoperative analgesia in laparoscopic surgeries with small dose of preemptive ketamine: A comparative study of three small doses

Introduction: Preemptive N-methyl-D-aspartate (NMDA) receptor antagonist ketamine inhibits central sensitization in response to peripheral nociception. The purpose of our study was to compare efficacy of three small doses of ketamine for improving postoperative analgesia after laparoscopic surgeries. Materials and Methods: A total of 120 patients of American Society of Anesthesiologists physical status I–II undergoing laparoscopic surgeries were randomly allocated into four groups. Groups 1, 2, and 3 received intravenous ketamine in dose of 1, 0.75, and 0.5 mg/kg, respectively, and control Group 4 received isotonic saline 30 min before incision. Variations in heart rate and mean arterial pressure were noted, and response to pain at rest and at deep breathing was studied over 24 h. Fentanyl 0.5 μg/kg was used for rescue analgesia. Results: Visual analog scale score was significantly low in Groups 1, 2, and 3 as compared to control Group 4. 66.7% of patients in Group 4 required rescue analgesia at 24 h which was significantly higher ( P Conclusion: Preemptive administration of ketamine decreases postoperative analgesic requirement with satisfactory hemodynamic stability and no side effects in 0.5 mg/kg dose.

Preemptive analgesia of oral clonidine during subarachnoid block for laparoscopic gynecological procedures: A prospective study.

Background:Preemptive analgesia is known modality to control the peri-operative pain. The present study was aimed to evaluate the effects of oral clonidine on subarachnoid block characteristics, hemodynamic changes, sedation and respiratory efficiency in patients undergoing laparoscopic gynecological procedures.Patients and Methods:A total of 64 adult consenting females of American Society of Anesthesiologist physical status I and II were randomized double blindly into two groups of 32 patients each. Patients in the clonidine group received oral clonidine (100 μg) and patients of the control group received placebo capsule, 90 min before subarachnoid block with 0.5% hyperbaric bupivacaine (3.5 ml). The onset of sensory and motor block, maximum cephalic sensory level and regression times of sensory and motor blockade were assessed. Intra-operative hemodynamic changes, respiratory efficiency, shoulder pain and sedation score were recorded. The other side-effects, if any were noted and managed.Results:The onset of sensory blockade was earlier in patients of clonidine group with prolonged duration of analgesia (216.4 ± 23.3 min vs. 165.8 ± 37.2 min, P < 0.05), but no significant difference was observed on motor blockade between groups. The hemodynamic parameters and respiratory efficiency were maintained within physiological limits in patients of clonidine group and no patient experienced shoulder pain. The Ramsey sedation score was 2.96 ± 0.75. In the control group, 17 patients experienced shoulder pain, which was effectively managed with small doses of ketamine and 15 patients required midazolam for anxiety.Conclusion:Premedication with oral clonidine (100 μg) has enhanced the onset and prolonged the duration of spinal analgesia, provided sedation with no respiratory depression. The hemodynamic parameters remained stabilized during the pneumoperitoneum.

Prevention of propofol-induced pain in children: pretreatment with small doses of ketamine

Study ObjectiveTo evaluate the efficacy of ketamine in preventing propofol injection pain in children. DesignProspective, randomized, double-blinded, placebo-controlled study. SettingUniversity-affiliated hospital. Patients192 ASA physical status 1 and 2 pediatric patients. InterventionsPatients were randomly assigned to 4 groups. Group S (control) received normal saline as a placebo; Group K1, Group K3, and Group K5 received 0.1 mg/kg, 0.3 mg/kg, and 0.5 mg/kg of ketamine, respectively. Fifteen seconds after the ketamine injection, patients were injected with propofol at a rate of 12 mL/min until loss-of-eyelash reflex. MeasurementPain was evaluated blindly at the time of induction using a 4-point scale: 0 = no pain, 1 = mild pain, 2 = moderate pain, and 3 = severe pain. Adverse effects were recorded. Characteristics of induction of anesthesia, such as dose of propofol and time from propofol injection to loss of consciousness (induction duration), were noted. Main Results39 (84.8%) Group S (control) patients had pain. Pretreatment with ketamine reduced the frequency of pain significantly to 56.5%, 17.0%, and 14.9% in Groups K1, K3, and K5, respectively. Furthermore, the frequency of moderate and severe pain in Group K1 (21.8%), Group K3 (6.4%), and Group K5 (4.3%) was significantly (P < 0.001, respectively) reduced compared with Group S (76.1%). Moreover, the dose of propofol for induction in Group K5 was smaller than in Group S, Group K1, and Group K3 (P < 0.05). One patient in Group K5 had emergence agitation. ConclusionPretreatment with a small dose of ketamine (0.3 mg/kg) reduced the frequency and intensity of propofol injection pain without severe adverse effects.

Efficacy of thoracic epidural anesthesia for laparoscopic cholecystectomy.

Background:Laparoscopic cholecystectomy is performed to minimize the postoperative morbidity and early return to work. This study was planned to evaluate the efficacy and feasibility of thoracic epidural anesthesia for laparoscopic cholecystectomy, so that it can be later used as anesthetic technique in patients when general anesthesia is not feasible.Materials and Methods:Forty-eight adult consented patients of ASA grade I and II of either sex scheduled for elective laparoscopic cholecystectomy were enrolled for thoracic epidural anesthesia with 15 ml of 0.75% ropivacaine and 50 μg fentanyl. Intraoperative hemodynamic parameters and respiratory efficiency were recorded. Intra-operatively patient anxiety, pain, vomiting, hypotension or any other adverse event was managed with appropriate drug regime. Postoperative pain management with epidural analgesia, and bowel recovery were also recorded.Results:The thoracic epidural anesthesia was effective for laparoscopic cholecystectomy in all except in two patients where conversion to general anesthesia was required. The hemodynamic parameters and respiratory efficiency were maintained within physiological limits. Only 4 patients required treatment for hypotension with vasopressor and 15 patients experienced shoulder pain, which was effectively managed with small doses of ketamine. The midazolam was required only in 11 patients for anxiety. The mean surgical time was 56.8±51.6 min. The 24-hour postoperative epidural infusion for analgesia was effective with limited effects on bowel and bladder function. Postoperatively only 3 patients had an episode of vomiting. There was good surgeon and patient's satisfaction.Conclusions:The thoracic epidural anesthesia with 0.75% ropivacaine and fentanyl for elective laparoscopic cholecystectomy is efficacious and has preserved ventilation and hemodynamic changes within physiological limits during pneumoperitoneum with minimal treatable side effects.

Prevention of Emergence Agitation After Sevoflurane Anesthesia for Pediatric Cerebral Magnetic Resonance Imaging by Small Doses of Ketamine or Nalbuphine Administered Just Before Discontinuing Anesthesia

Prevention of Emergence Agitation After Sevoflurane Anesthesia for Pediatric Cerebral Magnetic Resonance Imaging by Small Doses of Ketamine or Nalbuphine Administered Just Before Discontinuing Anesthesia

Prevention of Emergence Agitation After Sevoflurane Anesthesia for Pediatric Cerebral Magnetic Resonance Imaging by Small Doses of Ketamine or Nalbuphine Administered Just Before Discontinuing Anesthesia

Magnetic resonance imaging (MRI) requires long-lasting immobilization that frequently can only be provided by general anesthesia in pediatric patients. Sevoflurane provides adequate anesthesia but many patients experience emergence agitation. Small doses of ketamine and nalbuphine provide moderate sedation but their benefits have subsided at the time of emergence. We hypothesized that delaying their administration until the end of the procedure would prevent emergence agitation without prolonging patient wake-up and discharge times from the postanesthesia care unit. We performed a double-blind study involving 90 patients (aged 6 mo to 8 yr) randomly allocated to 1 of 3 groups receiving either saline (S-group), ketamine (0.25 mg/kg) (K-group), or nalbuphine (0.1 mg/kg) (N-group) at the end of an MRI procedure under sevoflurane anesthesia. We evaluated emergence conditions, sedation/agitation status and completion of discharge criteria at 30 min. The three groups were comparable in age, sex ratio, physical status, and associated medical disorders. Emergence conditions did not differ significantly. There were significantly more agitated children, at all times, in the S-group and more obtunded patients at early times (5 and 10 min) in both K- and N-groups. All patients met discharge criteria at 30 min but significantly more children were awake and quiet in the K-group and still more in the N-group. In conclusion, small doses of ketamine or nalbuphine administered at the end of an MRI procedure under sevoflurane anesthesia reduce emergence agitation without delaying discharge. Nalbuphine provided better results than ketamine.

Anesthesia for electroconvulsive therapy.

Anesthesia for electroconvulsive therapy.

Cerebral blood flow and metabolism following ketamine administration.

The effects of ketamine on cerebral blood flow (CBF), cerebral metabolic rate (CMRO2) and intracranial pressure (ICP) were evaluated in ventilated or spontaneously breathing goats after peripheral administration of 5 mg . kg-1 and central administration of 0.1-2.0 mg. In mechanically ventilated normocarbic goats intravenous ketamine 5 mg . kg-1 had no effect on CBF, but did produce a significant reduction in CMRO2 (4.3 +/- 0.4 vs 3.7 +/- 0.3 ml O2 . min-1/100 g) five minutes after injection. However, in spontaneously breathing goats, ketamine caused a significant increase in CBF (77 +/- 7 vs 109 +/- 12 ml . min-1/100 g), a significant reduction in CMRO2 (4.3 +/- 0.3 vs 3.8 +/- 0.4) and an increase of PCO2 from 4.5 +/- 0.5 to 5.4 +/- 0.9 kPa (34 +/- 4 to 41 +/- 7 torr). Small doses of ketamine (0.1-2.0 mg) injected directly into the cerebral circulation failed to cause any significant change in CBF. Intracranial pressure showed a significant increase from 13 +/- 3 to 19 +/- 3 mm Hg in spontaneously breathing goats and no change in ventilated goats. These data suggest that ketamine is a mild depressant of cerebral metabolic rate and has no other cerebral vascular effects.

Cardiovascular effects of centrally administered ketamine in goats.

The cardiovascular effects of centrally and peripherally administered ketamine were evaluated in unanesthetized goats and in goats anesthetized with pentobarbital. Small doses of ketamine (0.1 to 4 mg.) were injected directly into the central nervous system (CNS) of the unanesthetized goats via a temporal artery catheter, while cerebral blood flow (CBF), cardiac output (C.O.), systemic blood pressure (B.P.), and heart rate (H.R.) were continuously monitored. Administered by this route, ketamine produced an immediate increase in mean systemic B.P., C.O., and H.R. Changes in CBF were variable, increasing on some occasions and decreasing on others. Cardiovascular changes were not the result of alterations in blood gases, since these remained unchanged. When ketamine, 0.1 to 4 mg., was injected into the temporal artery of goats anesthetized with pentobarbital, no changes were observed in B.P., C.O., H.R. or CBF. Ketamine (2 mg./kg.) intravenously administered to unanesthetized goats produced anesthesia and an increase in B.P., C.O., H.R., CBF, and arterial carbon dioxide (Paco2) levels. Administered by the same route and dosage in mechanically ventilated goats previously anesthetized with sodium pentobarbital, ketamine did not produce any changes in cardiovascular or blood-gas measurements. It was therefore concluded that ketamine produces peripheral sympathomimetic effects primarily by direct stimulation of CNS structures, and that when these structures are depressed by pentobarbital, the peripheral effects of ketamine are ameliorated.