Effects of the addition of low-dose ketamine to propofol-fentanyl anaesthesia during diagnostic gynaecological laparoscopy

Effects of intra-operative administration of subanesthetic s-ketamine on emergence from sevoflurane anesthesia: a randomized double-blind placebo-controlled study

BACKGROUND

Ketamine is administered in the perioperative period for its benefits in analgesia, anti-agitation and anti-depression when administered at a small dose. However, it is not clear whether the intra-operative administration of ketamine would affect emergence under sevoflurane anesthesia. To investigate this effect, we designed this trial.

METHODS

In this randomized, double-blind, placebo-controlled study, we enrolled 44 female patients aged 18-60 who were scheduled to elective laparoscopic gynecological surgeries. All patients were randomly assigned to saline or s-ketamine group. In s-ketamine group, patients received 0.125 mg/kg s-ketamine 30 min after the start of surgery. In saline group, patients were administered the same volume of saline. Sevoflurane and remifentanil were used to maintain general anesthesia. The primary outcome was emergence time. We also assessed postoperative agitation, cognitive function, and delirium. In addition, we collected and analyzed prefrontal electroencephalogram (EEG) during and after general anesthesia.

RESULTS

There were no significant differences in emergence time between s-ketamine group and saline group (10.80 ± 3.77 min vs. 10.00 ± 2.78 min, P = 0.457). Neither postoperative agitation (4 [3, 4] vs. 4 [3, 4], P = 0.835) nor cognitive function (25.84 ± 2.69 vs. 25.55 ± 2.19, P = 0.412) differed between groups. No postoperative delirium was observed in either group. Subanesthetic s-ketamine resulted in active EEG with decreased power of slow (-0.35 ± 1.13 dB vs. -1.63 ± 1.03 dB, P = 0.003), delta (-0.22 ± 1.11 dB vs. -1.32 ± 1.09 dB, P = 0.011) and alpha (-0.31 ± 0.71 dB vs. -1.71 ± 1.34 dB, P = 0.0003) waves and increased power of beta-gamma bands (-0.30 ± 0.89 dB vs. 4.20 ± 2.08 dB, P < 0.0001) during sevoflurane anesthesia, as well as an increased alpha peak frequency (-0.16 ± 0.48 Hz vs. 0.31 ± 0.73 Hz, P = 0.026). EEG patterns did not differ during the recovery period after emergence between groups.

CONCLUSION

Ketamine administered during sevoflurane anesthesia had no apparent influence on emergence time in young and middle-aged female patients undergoing laparoscopic surgery. Subanesthetic s-ketamine induced an active prefrontal EEG pattern during sevoflurane anesthesia but did not raise neurological side effects after surgery.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2100046479 (date: 16/05/2021).

Monitored Anesthesia Care Using Remimazolam and Ketamine Combination for Brief Gynecological Surgeries: A Report for Four Cases

Remimazolam is a benzodiazepine with rapid onset and recovery time. Ketamine provides analgesia and sedation without compromising hemodynamics. Combining both agents may provide good anesthesia and analgesia with fewer complications. We report four cases of monitored anesthesia care with a combination of remimazolam and ketamine for brief gynecological surgeries. We applied 0.5 mg/kg bolus ketamine and infused patients with remimazolam at 6 mg/kg/h for induction and 1 mg/kg/h for maintenance. Then, 25 µg of fentanyl was administered for analgesia 4 min before the procedure, and additional fentanyl was administered as needed. Remimazolam was discontinued shortly after surgery. We conducted satisfactory monitored anesthesia care with a combination of remimazolam and ketamine in all four cases.

Comparison of haemodynamic changes between propofol and ketofol as induction agents in patients undergoing laparoscopic surgeries under general anaesthesia

Background and Aims:

Laparoscopic surgeries are more commonly performed procedure nowadays because of its advantages however generation of pneumoperitoneum causes significant physiological changes. Propofol is the most commonly used induction agent but its use is limited by its side effects like dose-dependent hypotension and myocardial depression. So by combining propofol with ketamine to form ketofol may result in better hemodynamic stability. The aim of this study was to compare the haemodynamic changes in patients undergoing laparoscopic surgery under general anesthesia using propofol and ketofol as induction agents.

Material and Methods:

In this prospective randomized double blind study, 80 patients of ASA I/II undergoing elective laparoscopic surgery were randomized into two Groups. Group A received 1 mg/kg of propofol + 1 mg/kg ketamine made up to a total volume of 20 ml with normal saline and Group B received 2 mg/kg propofol + normal saline to make up to an equal volume. Hemodynamic profiles like HR, SBP, DBP, and MAP were recorded at different time intervals until pneumoperitoneum. Postoperative recovery profile and complications were recorded. All data were entered in MS excel and analyzed using SPSS Version 20.0. Repeated measures ANOVA and Chi-square test were used to test the level of significance.

Results:

Demographic character and duration of surgery were comparable. SBP, DBP, MAP and HR showed statistically significant difference in both groups in various time intervals with P < 0.05 with Group A (ketofol ) having a better hemodynamic stability. Recovery profile in ketofol group took longer duration (4.95 min) compared to propofol group B (1.8 min). Postoperative nausea and vomiting were significant (P = 0.004) in ketofol group.

Conclusion:

We concluded that ketofol had a better hemodynamic stability compared to propofol as an induction agent, however time for recovery in ketofol group took a longer period compared to propofol group, with no complication in either groups.

Comparison of the Effect of Ketamine and Dexmedetomidine Combined with Total Intravenous Anesthesia in Laparoscopic Cholecystectomy Procedures: A Prospective Randomized Controlled Study

This randomized prospective clinical study aimed to investigate the effects of dexmedetomidine or ketamine administration to total intravenous anesthesia (TIVA) on postoperative analgesia in subjects undergoing elective laparoscopic cholecystectomy procedures. 90 adults, American Society of Anesthesiologists (ASA) physical status 1 and II patients, who underwent elective laparoscopic cholecystectomy procedures were included in the study and randomized into three groups equally. Remifentanil, propofol, and rocuronium infusions were used for TIVA guided by the bispectral index. In group KETA, 10 μg/kg/min ketamine was added to TIVA before surgery, and in group DEX, 0.5 μg/kg/h dexmedetomidine was added to TIVA before surgery. Normal saline infusions were infused in the control group. Postoperative analgesia was provided with intravenous patient-controlled analgesia (PCA) morphine (1 mg bolus morphine, 5 min lockout time). Hemodynamic parameters, scores of visual analogue scale (VAS) for pain, rescue morphine requirements, and side effects such as sedation, nausea, and vomiting were recorded for 48 hours after surgery. Postoperative first analgesic requirement time was longer in group KETA (P < 0.001), and it was longer in group DEX than in the control group (P < 0.001). Pain scores were lower in group KETA and group DEX than in the control group at all corresponding times throughout the 48 h period of observation. Intravenous PCA morphine consumptions were higher in the control group than in group KETA (P < 0.001 for all followed-up times), and they were higher in group DEX than in group KETA (P < 0.001 for all followed-up times). It is concluded that the use of dexmedetomidine or ketamine infusions can be suitable as an additive for TIVA in the intraoperative period. Furthermore, the addition of both drugs to the TIVA protocol may improve postoperative pain relief and decrease opioid consumption.

Comeback of ketamine: resurfacing facts and dispelling myths

Initially known as CI-581, ketamine was first synthesized in 1962 as a replacement from phencyclidine. It has since been used as an anesthetic and analgesic. In addition, it has bronchodilating, sedative, and amnestic properties, preserving airway reflexes and sympathetic nervous system tone. Since the discovery of ketamine, it has been a major topic of discussion due to controversies regarding its usage in particular sets of patients. In the past 50 years, despite its potential benefits, it is not commonly used because of concerns of "emergence phenomenon," its use as a substance of abuse, and its systemic side effects. Since 2012, three World Health Organization reviews on ketamine have addressed its international control. Researchers have been studying this wonder drug for a decade worldwide. Many myths of ketamine regarding emergence phenomenon and its use in traumatic brain injury and open eye injury have been disproved in recent times. It is becoming popular in pre-hospital settings, critical care, emergency medicine, low-dose acute pain services, and adjuvant in regional anesthesia techniques. This review highlights the current consensus on the various applications of ketamine in the literature.

Comparision of Dexmedetomidine and Propofol in Patients Undergoing Laparoscopic Cholecystectomy Under Spinal Anesthesia

Background:

Spinal anesthesia (SA) with sedation is considered to be an alternative to general anesthesia for laparoscopic cholecystectomy (LC) in high-risk patients. Ketamine in analgesic dose with propofol or dexmedetomidine infusion provides titratable sedation, hemodynamic stability, and minimum respiratory depression without psychomimetic effects.

Aim:

To compare the efficacy of ketamine–dexmedetomidine and ketamine-propofol combination in relation to sedation, analgesia, hemodynamic effects, and perioperative side effects.

Settings and Design:

This was a prospective, randomized single-blind comparative study comprising 100 American Society of Anesthesiologists I, II, and III patients posted for LC.

Materials and Methods:

Patients were randomized into two groups of 50 patients each. Group KP (ketamine + propofol) received intravenous (i.v.) bolus of injection ketamine 0.5 mg.kg ⁻¹ and propofol infusion at 3 mg.kg ⁻¹.h ⁻¹. Group KD (ketamine + dexmedetomidine) received i.v. bolus of injection ketamine 0.5 mg.kg ⁻¹ and dexmedetomidine infusion at 0.4 μg.kg ⁻¹.h ⁻¹. Parameters observed were vitals, perioperative side effects, time to first rescue analgesia, and return of consciousness.

Statistical Analysis:

Student's independent t-test was employed for comparing continuous variables. Chi-square test or Fisher's exact test, whichever appropriate, was applied for comparing categorical variables.

Results:

Duration of analgesia was longer in KD Group (191.2 vs. 173.5 min), and time to regain consciousness was faster in KP Group (14.9 vs. 20.4 min).

Conclusion:

Both the techniques of sedation are feasible, safe, and comparable, except the duration of analgesia and time to regain consciousness which was longer in KD Group.

Effects of the addition of low-dose ketamine to propofol anesthesia in the dental procedure for intellectually disabled patients

Background

This study aimed to examine whether the combination of low-dose ketamine and propofol in deep sedation is clinically useful in controlling the behavior in intellectually disabled patients who are typically extremely noncooperative during dental procedures.

Methods

A total of 107 extremely noncooperative intellectually disabled adult patients were analyzed. In all patients, deep sedation was performed using either propofol alone (group P) or using a combination of propofol and 0.2 mg/kg or 0.4 mg/kg ketamine (groups PK0.2 and PK0.4, respectively). The procedures were performed in the order of insertion of nasal cannula into the nostril, attachment of mouth gag, and mouth cleaning and scaling. The frequency of patient movement during the procedures, mean arterial pressure, heart rate, peripheral oxygen saturation, recovery time, discharge time, and postoperative nausea and vomiting were examined.

Results

The three groups were significantly different only in the frequency of patient movement upon stimulation during single intravenous injection of propofol and scaling.

Conclusion

For propofol deep sedation, in contrast to intravenous injection of propofol alone, prior intravenous injection of low-dose ketamine (0.4 mg/kg) is clinically useful because it neither affects recovery, nor causes side effects and can suppress patient movement and vascular pain during procedures.

Perioperative intravenous ketamine for acute postoperative pain in adults

BACKGROUND

Inadequate pain management after surgery increases the risk of postoperative complications and may predispose for chronic postsurgical pain. Perioperative ketamine may enhance conventional analgesics in the acute postoperative setting.

OBJECTIVES

To evaluate the efficacy and safety of perioperative intravenous ketamine in adult patients when used for the treatment or prevention of acute pain following general anaesthesia.

SEARCH METHODS

We searched CENTRAL, MEDLINE and Embase to July 2018 and three trials registers (metaRegister of controlled trials, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP)) together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials of adults undergoing surgery under general anaesthesia and being treated with perioperative intravenous ketamine. Studies compared ketamine with placebo, or compared ketamine plus a basic analgesic, such as morphine or non-steroidal anti-inflammatory drug (NSAID), with a basic analgesic alone.

DATA COLLECTION AND ANALYSIS

Two review authors searched for studies, extracted efficacy and adverse event data, examined issues of study quality and potential bias, and performed analyses. Primary outcomes were opioid consumption and pain intensity at rest and during movement at 24 and 48 hours postoperatively. Secondary outcomes were time to first analgesic request, assessment of postoperative hyperalgesia, central nervous system (CNS) adverse effects, and postoperative nausea and vomiting. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included 130 studies with 8341 participants. Ketamine was given to 4588 participants and 3753 participants served as controls. Types of surgery included ear, nose or throat surgery, wisdom tooth extraction, thoracotomy, lumbar fusion surgery, microdiscectomy, hip joint replacement surgery, knee joint replacement surgery, anterior cruciate ligament repair, knee arthroscopy, mastectomy, haemorrhoidectomy, abdominal surgery, radical prostatectomy, thyroid surgery, elective caesarean section, and laparoscopic surgery. Racemic ketamine bolus doses were predominantly 0.25 mg to 1 mg, and infusions 2 to 5 µg/kg/minute; 10 studies used only S-ketamine and one only R-ketamine. Risk of bias was generally low or uncertain, except for study size; most had fewer than 50 participants per treatment arm, resulting in high heterogeneity, as expected, for most analyses. We did not stratify the main analysis by type of surgery or any other factor, such as dose or timing of ketamine administration, and used a non-stratified analysis.Perioperative intravenous ketamine reduced postoperative opioid consumption over 24 hours by 8 mg morphine equivalents (95% CI 6 to 9; 19% from 42 mg consumed by participants given placebo, moderate-quality evidence; 65 studies, 4004 participants). Over 48 hours, opioid consumption was 13 mg lower (95% CI 10 to 15; 19% from 67 mg with placebo, moderate-quality evidence; 37 studies, 2449 participants).Perioperative intravenous ketamine reduced pain at rest at 24 hours by 5/100 mm on a visual analogue scale (95% CI 4 to 7; 19% lower from 26/100 mm with placebo, high-quality evidence; 82 studies, 5004 participants), and at 48 hours by 5/100 mm (95% CI 3 to 7; 22% lower from 23/100 mm, high-quality evidence; 49 studies, 2962 participants). Pain during movement was reduced at 24 hours (6/100 mm, 14% lower from 42/100 mm, moderate-quality evidence; 29 studies, 1806 participants), and 48 hours (6/100 mm, 16% lower from 37 mm, low-quality evidence; 23 studies, 1353 participants).Results for primary outcomes were consistent when analysed by pain at rest or on movement, operation type, and timing of administration, or sensitivity to study size and pain intensity. No analysis by dose was possible. There was no difference when nitrous oxide was used. We downgraded the quality of the evidence once if numbers of participants were large but small-study effects were present, or twice if numbers were small and small-study effects likely but testing not possible.Ketamine increased the time for the first postoperative analgesic request by 54 minutes (95% CI 37 to 71 minutes), from a mean of 39 minutes with placebo (moderate-quality evidence; 31 studies, 1678 participants). Ketamine reduced the area of postoperative hyperalgesia by 7 cm² (95% CI -11.9 to -2.2), compared with placebo (very low-quality evidence; 7 studies 333 participants). We downgraded the quality of evidence because of small-study effects or because the number of participants was below 400.CNS adverse events occurred in 52 studies, while 53 studies reported of absence of CNS adverse events. Overall, 187/3614 (5%) participants receiving ketamine and 122/2924 (4%) receiving control treatment experienced an adverse event (RR 1.2, 95% CI 0.95 to 1.4; high-quality evidence; 105 studies, 6538 participants). Ketamine reduced postoperative nausea and vomiting from 27% with placebo to 23% with ketamine (RR 0.88, 95% CI 0.81 to 0.96; the number needed to treat to prevent one episode of postoperative nausea and vomiting with perioperative intravenous ketamine administration was 24 (95% CI 16 to 54; high-quality evidence; 95 studies, 5965 participants).

AUTHORS' CONCLUSIONS

Perioperative intravenous ketamine probably reduces postoperative analgesic consumption and pain intensity. Results were consistent in different operation types or timing of ketamine administration, with larger and smaller studies, and by higher and lower pain intensity. CNS adverse events were little different with ketamine or control. Perioperative intravenous ketamine probably reduces postoperative nausea and vomiting by a small extent, of arguable clinical relevance.

Intranasal Ketamine Administration for Narcotic Dose Decrement in Patients Suffering from Acute Limb Trauma in Emergency Department: a Double-Blind Randomized Placebo-Controlled Trial

Introduction:

pain management is an important and challenging issue in emergency medicine. Despite the conduct of several studies on this topic, pain is still handled improperly in many cases.

Objective:

This study investigated the effectiveness of low-dose IN ketamine administration in reducing the need for opiates in patients in acute pain resulting from limb injury.

Method:

This randomized, double-blind, placebo-controlled trial was conducted to assess the possible effect of low-dose intranasal (IN) ketamine administration in decreasing patients' narcotic need. Patients in emergency department suffering from acute isolated limb trauma were included. One group of patients received 0.5 mg/kg intravenous morphine sulfate and 0.02 ml/kg IN ketamine. The other group received the same dose of morphine sulfate and 0.02 ml/kg IN distilled water. Pain severity was measured using the 11 points numerical rating scale at 0, 10, 30, 60, 120, and 180 minutes.

Results:

Ninety-one patients with mean age of 31.59 ± 11.33 years were enrolled (38.8% female). The number of requests for supplemental medication was significantly lower in patients who received ketamine (12 patients (30%)) than those who received placebo (27 patients (67.5%)) (p = 0.001).

Conclusion:

It is likely that low-dose IN ketamine is effective in reducing the narcotic need of patients suffering from acute limb trauma.

Efficacy of ketamine for postoperative pain following robotic thyroidectomy: A prospective randomised study

Objective

Although robotic thyroidectomy (RoT) is a minimally invasive surgery, percutaneous tunneling causes moderate to severe pain immediately postoperatively. We evaluated the efficacy of ketamine for postoperative pain management in patients following RoT.

Methods

Sixty-four patients scheduled for RoT were randomly divided into two groups. In the ketamine group (n = 32), ketamine was infused from induction of anaesthesia until the end of the procedure (0.15-mg/kg bolus with continuous infusion at 2 µg/kg/min). In the control group (n = 32), the same volume of saline was infused. Visual analogue scale (VAS) scores for acute and chronic pain, the incidence of hypoesthesia, postoperative analgesic requirements, and complications related to opioids or ketamine were compared between the two groups.

Results

The VAS pain scores were significantly lower in the ketamine group up to 24 h postoperatively. The VAS pain score when coughing was significantly higher in the control group than in the ketamine group at 24 h postoperatively. A significantly greater proportion of patients in the control group required rescue analgesics. Complications were comparable in both groups.

Conclusions

Ketamine infusion decreased pain scores for 24 h postoperatively and reduced analgesic requirements without serious complications in patients following RoT.

Trial Registration: Clinicaltrials.gov Identifier: NCT01997801

Efficacy of Low-dose Ketamine as Sole Analgesic Agent in Maintaining Analgesia and Intraoperative Hemodynamics During Laparoscopic Gynecological Surgeries

BACKGROUND

Ketamine, in low doses, is known to possess intense analgesic properties. The available literature shows wide variation regarding the time and dose of administration of ketamine during surgery.

AIM

The aim of this study was to evaluate the effect of intraoperative administration of ketamine when used as sole analgesic in low doses, on hemodynamics and postoperative analgesia in patients undergoing laparoscopic gynecological surgery and compared on the basis of duration of surgery.

SETTINGS AND DESIGN

This prospective, observational study was conducted from July to December 2015, over a period of 6 months in a tertiary care medical college and hospital.

MATERIALS AND METHODS

Seventy patients between 23 and 55 years planned for laparoscopic gynecological surgery were recruited. Ketamine was given in a dose of 0.5 mg/kg preoperatively and then repeated every ½ hourly in a dose of 0.25 mg/kg throughout the surgery. Hemodynamic parameters, time to the first rescue analgesia and complications were recorded for the first 8 h. Statistical evaluation was done and result expressed as percentage. Paired t-test was employed for the comparison of numerical variables within the group.

RESULTS

Seventy percent of the patients did not require any postoperative rescue analgesia during the first 8 h after surgery. None of the patients complained of pain immediately after extubation, and 16% of the patients had minor postoperative complications. The intraoperative hemodynamic profile was significantly altered. Duration of surgery and dose of ketamine required did not affect the duration of analgesia.

CONCLUSION

Ketamine in low dose proved to be an efficacious analgesic even in the long duration laparoscopic gynecological surgeries. It stabilizes intraoperative hemodynamics thereby reducing the requirement of other anesthetic and antihypertensive agents.

Combined Ketamine-Tramadol Subcutaneous Wound Infiltration for Multimodal Postoperative Analgesia: A Double-Blinded, Randomized Controlled Trial after Renal Surgery

Background

Pain is an important consideration after renal surgery. A multimodal approach to postoperative pain management could enhance analgesia by risking fewer side effects after surgery.

Objectives

The aim of this study was to evaluate the clinical efficacy of the subcutaneous infiltration of ketamine and tramadol at the incision site to reduce postoperative pain.

Methods

Sixty-four patients between 18 and 80 years old who were scheduled for elective renal surgery were enrolled in a double-blind randomized controlled study. At the end of the surgery, patients were divided into four groups with 16 patients in each group: the saline group, who were treated with 10 mL of saline solution; the K group, who were treated with 1 mg/kg etamine in 10 mL of saline solution; the T group, who were treated with 1 mg/kg tramadol in 10 mL of saline solution; and the K/T group, who were treated with 0.5 mg/kg ketamine with 0.5 mg/kg tramadol in 10 mL of saline solution. In each group, the solution was infiltrated subcutaneously at the incision site. The postoperative pain scores and rescue analgesic consumption of the patients in each group were recorded for 24 hours and compared. The primary goal of the study was to compare the results of patients treated with a combined ketamine and tramadol subcutaneous wound infiltration, patients treated with a tramadol subcutaneous wound infiltration, and patients treated with a ketamine subcutaneous wound infiltration.

Results

Sixty-four patients were enrolled in the study. Pain intensity and cumulative meperidine consumption were significantly lower in the K/T group (27 mg; 95% confidence interval, 25.2 - 53.2) in comparison with the group that received a saline infusion during the first 24 hours after surgery (P < 0.001). The sedation score of the K, T, and K/T groups were significantly higher than the saline group (P < 0.001).

Conclusions

The combined subcutaneous infiltration of ketamine and tramadol at the incision site produces better analgesia and an opioid-sparing effect during the first 24 hours when compared with the control group and the groups that received a subcutaneous infiltration of only ketamine or tramadol.

Ketamine use in current clinical practice

After nearly half a century on the market, ketamine still occupies a unique corner in the medical armamentarium of anesthesiologists or clinicians treating pain. Over the last two decades, much research has been conducted highlighting the drug's mechanisms of action, specifically those of its enantiomers. Nowadays, ketamine is also being utilized for pediatric pain control in emergency department, with its anti-hyperalgesic and anti-inflammatory effects being revealed in acute and chronic pain management. Recently, new insights have been gained on ketamine's potential anti-depressive and antisuicidal effects. This article provides an overview of the drug's pharmacokinetics and pharmacodynamics while also discussing the potential benefits and risks of ketamine administration in various clinical settings.

Ketamine: Current applications in anesthesia, pain, and critical care

Ketamine was introduced commercially in 1970 with the manufacturer's description as a "rapidly acting, nonbarbiturate general anesthetic" and a suggestion that it would be useful for short procedures. With the help of its old unique pharmacological properties and newly found beneficial clinical properties, ketamine has survived the strong winds of time, and it currently has a wide variety of clinical applications. It's newly found neuroprotective, antiinflammatory and antitumor effects, and the finding of the usefulness of low dose ketamine regimens have helped to widen the clinical application profile of ketamine. The present article attempts to review the current useful applications of ketamine in anesthesia, pain and critical care. It is based on scientific evidence gathered from textbooks, journals, and electronic databases.