The Effects of Small-Dose Ketamine on Propofol Sedation: Respiration, Postoperative Mood, Perception, Cognition, and Pain

Comparison of airway collapsibility following single induction dose ketamine with propofol versus propofol sedation in children undergoing magnetic resonance imaging: A randomised controlled study

Background and Aims

Adequate sedation is essential for children undergoing magnetic resonance imaging (MRI) console. Propofol is commonly used for sedation, but it has the drawback of upper airway collapse at higher doses, which may be overcome by ketamine. This study was designed to evaluate the beneficial effect of ketamine on propofol in preventing airway collapse.

Methods

Fifty-eight children undergoing MRI were randomised to Group P (propofol bolus dose followed by infusion or Group KP (bolus dose of ketamine and propofol followed by propofol infusion). The primary aim is to compare the upper airway cross-sectional area (CSA) and diameters (transverse diameter [TD] and anteroposterior diameter [APD]) obtained from MRI during inspiration and expiration.

Results

Upper airway collapse as measured by delta CSA in mean (SD) [95% confidence interval] was statistically more significant between the two groups [at the soft palate level, 16.9 mm2 (19.8) [9.3-24.4] versus 9.0 mm2 (5.50) [6.9-11.1] (P = 0.043); at the base of the tongue level, 15.4 mm2 (11.03) [11.2-19.6] versus 7.48 mm2 (4.83) [5.64-9.32] (P < 0.001); at the epiglottis level, 23.9 (26.05) [14.0-33.8] versus 10.9 mm2 (9.47) [7.35-14.5] (P = 0.014)]. A significant difference was obtained for TD at all levels and for APD at the soft palate and base of tongue level.

Conclusion

Adding a single dose of ketamine to propofol reduced the upper airway collapse significantly, as evidenced by the MRI-based measurements of upper airway dimensions, compared to propofol alone.

Randomized trial of ketamine masked by surgical anesthesia in patients with depression

Ketamine may have antidepressant properties, but its acute psychoactive effects complicate successful masking in placebo-controlled trials. We present a single-center, parallel-arm, triple-masked, randomized, placebo-controlled trial assessing the antidepressant efficacy of intravenous ketamine masked by surgical anesthesia (ClinicalTrials.gov, NCT03861988). Forty adult patients with major depressive disorder who were scheduled for routine surgery were randomized to a single infusion of ketamine (0.5 mg/kg) or placebo (saline) during usual anesthesia. All participants, investigators, and direct patient care staff were masked to treatment allocation. The primary outcome was depression severity measured by the Montgomery-Åsberg Depression Rating Scale (MADRS) at 1, 2, and 3 days post-infusion. After all follow-up visits, participants were asked to guess which intervention they received. A mixed-effects model showed no evidence of effect of treatment assignment on the primary outcome (-5.82, 95% CI -13.3 to 1.64, p=0.13). 36.8% of participants guessed their treatment assignment correctly; both groups allocated their guesses in similar proportions. In conclusion, a single dose of intravenous ketamine delivered during surgical anesthesia had no greater effect than placebo in acutely reducing the severity of depressive symptoms in adults with major depressive disorder. This trial successfully masked treatment allocation in moderate-to-severely depressed patients using surgical anesthesia. Although this masking strategy is impractical for most placebo-controlled trials, future studies of novel antidepressants with acute psychoactive effects should make efforts to fully mask treatment assignment in order to minimize subject-expectancy bias.

Randomized Trial of Ketamine Masked by Surgical Anesthesia in Depressed Patients

BACKGROUND

Ketamine may have antidepressant properties, but its acute psychoactive effects complicate successful masking in placebo-controlled trials.

METHODS

In a triple-masked, randomized, placebo-controlled trial, 40 adult patients with major depressive disorder were randomized to a single infusion of ketamine (0.5 mg/kg) or placebo (saline) during anesthesia as usual for routine surgery. The primary outcome was depression severity measured by the Montgomery-Åsberg Depression Rating Scale (MADRS) at 1, 2, and 3 days post-infusion. The secondary outcome was the proportion of participants with clinical response (≥50% reduction in MADRS scores) at 1, 2, and 3 days post-infusion. After all follow-up visits, participants were asked to guess which intervention they received.

RESULTS

Mean MADRS scores did not differ between groups at screening or pre-infusion baseline. The mixed-effects model showed no evidence of effect of group assignment on post-infusion MADRS scores at 1 to 3 days post-infusion (-5.82, 95% CI -13.3 to 1.64, p=0.13). Clinical response rates were similar between groups (60% versus 50% on day 1) and comparable to previous studies of ketamine in depressed populations. Secondary and exploratory outcomes did not find statistical separation of ketamine from placebo. 36.8% of participants guessed their treatment assignment correctly; both groups allocated their guesses in similar proportions. One serious adverse event occurred in each group, unrelated to ketamine administration.

CONCLUSION

In adults with major depressive disorder, a single dose of intravenous ketamine delivered during surgical anesthesia had no greater effect than placebo in acutely reducing the severity of depressive symptoms. This trial successfully masked treatment allocation in moderate-to-severely depressed patients using surgical anesthesia. While it is impractical to use surgical anesthesia for most placebo-controlled trials, future studies of novel antidepressants with acute psychoactive effects should make efforts to fully mask treatment assignment in order to minimize subject-expectancy bias. (ClinicalTrials.gov number, NCT03861988).

Ketamine-propofol (ketofol) in procedural sedation: a narrative review

Sedation methods for dental treatment are increasingly explored. Recently, ketofol, which is a combination of ketamine and propofol, has been increasingly used because the advantages and disadvantages of propofol and ketamine complement each other and increase their effectiveness. In this review, we discuss the pharmacology of ketamine and propofol, use of ketofol in various clinical situations, and differences in efficacy between ketofol and other sedatives.

The Effect of Preoperative Combined with Intravenous Lidocaine and Ketamine vs. Intravenous Ketamine on Pediatric Patients Undergoing Upper Gastrointestinal Endoscopy

Background

Ketamine is widely used in pediatric sedation. New studies have recommended combination therapy to reduce the side effects of ketamine.

Objectives

This study investigated the effect of adding intravenous (IV) lidocaine to ketamine on hemodynamic parameters, endoscopist satisfaction, and recovery time of children undergoing gastrointestinal endoscopy.

Methods

This triple-blind, randomized, controlled clinical trial was conducted in Isfahan, Iran (2021). One hundred twenty children between the ages of 1 and 6 were enrolled. Patients were divided into 2 groups. The intervention group received 1.0 mg/kg of IV lidocaine and 1.0 mg/kg of IV ketamine, and the placebo group received 1.0 mg/kg of IV ketamine and placebo 2 minutes before entering the endoscopic room. Patients in both groups were sedated with 1.0 mg/kg of propofol, 0.1 mg/kg of midazolam, and 2.0 ug/kg of fentanyl for the procedure. The pulse rate, mean arterial pressure (MAP), respiratory rate, and oxygen saturation were recorded 1 minute before injection and every 5 minutes afterward.

Results

The mean (SD) ages of the intervention and control groups were 3.4 (1.5) and 3.4 (1.7), respectively. The mean difference in hemodynamic parameters between the 2 groups was insignificant during the investigation (P > 0.05). Furthermore, no significant differences were found regarding endoscopist satisfaction scores and length of recovery room stay (P > 0.05).

Conclusions

Adding low-dose IV lidocaine to ketamine for pediatric sedation does not significantly affect the hemodynamic status, endoscopist satisfaction, and recovery time.

Efficacy and safety of subanesthetic doses of esketamine combined with propofol in painless gastrointestinal endoscopy: a prospective, double-blind, randomized controlled trial

Background

Painless gastrointestinal endoscopy is widely used for the diagnosis and treatment of digestive diseases. At present, propofol is commonly used to perform painless gastrointestinal endoscopy, but the high dose of propofol often leads to a higher incidence of cardiovascular and respiratory complications. Studies have shown that the application of propofol combined with ketamine in painless gastrointestinal endoscopy is beneficial to reduce the dosage of propofol and the incidence of related complications. Esketamine is dextrorotatory structure of ketamine with a twice as great anesthetic effect as normal ketamine but fewer side effects. We hypothesized that esketamine may reduce the consumption of propofol and to investigate the safety of coadministration during gastrointestinal endoscopy.

Methods

A total of 260 patients undergoing painless gastrointestinal endoscopy (gastroscope and colonoscopy) were randomly divided into P group (propofol + saline), PK1 group (propofol + esketamine 0.05 mg/kg), PK2 group (propofol + esketamine 0.1 mg/kg), and PK3 group (propofol + esketamine 0.2 mg/kg). Anesthesia was achieved by 1.5 mg/kg propofol with different doses of esketamine. Propofol consumption per minute was recorded. Hemodynamic index, pulse oxygen saturation, operative time, induction time, awakening status, orientation recovery time, adverse events, and Mini-Mental State Examination (MMSE) were also recorded during gastrointestinal endoscopy.

Results

Propofol consumption per minute was 11.78, 10.56, 10.14, and 9.57 (mg/min) in groups P, PK1, PK2, and PK3, respectively; compared with group P, groups PK2 and PK3 showed a decrease of 13.92% (P = 0.021) and 18.76% (P = 0.000), respectively. In all four groups, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), but not pulse oxygen saturation (SpO₂) significantly decreased (P = 0.000) immediately after administration of induction, but there were no significant differences between the groups. The induction time of groups P, PK1, PK2, and PK3 was 68.52 ± 18.394, 64.83 ± 13.543, 62.23 ± 15.197, and 61.35 ± 14.470 s, respectively (P = 0.041). Adverse events and psychotomimetic effects were observed but without significant differences between the groups.

Conclusions

The combination of 0.2 mg/kg esketamine and propofol was effective and safe in painless gastrointestinal endoscopy as evidenced by less propofol consumption per minute, shorter induction time, and lower incidence of cough and body movement relative to propofol alone. The lack of significant differences in hemodynamic results, anesthesia-related indices, adverse events, and MMSE results showed the safety to apply this combination for painless gastrointestinal endoscopy.

Trial registration This study was registered with China Clinical Trial Registration on 07/11/2020 (registration website: chictr.org.cn; registration numbers: ChiCTR https://clinicaltrials.gov/ct2/show/2000039750).

Intravenous Lidocaine Significantly Reduces the Propofol Dose in Elderly Patients Undergoing Gastroscopy: A Randomized Controlled Trial

Objective

Propofol-based sedation has been widely used for gastroscopy, but the risk of respiratory suppression in elderly patients should not be overlooked. Intravenous (IV) lidocaine during surgery can reduce the demand for propofol and the incidence of cardiopulmonary complications. We examined whether IV lidocaine reduces the dose of propofol and the occurrence of adverse events during gastroscopy in elderly patients.

Methods

We conducted a prospective, single-center, double-blind randomized controlled trial in elderly patients aged ≥65 years with ASA I-II. Subjects were randomly assigned to the lidocaine group (Group L, n=70), who received IV 1.5 mg kg⁻¹ lidocaine followed by a continuous infusion of 4 mg kg⁻¹ h⁻¹ lidocaine, or the normal saline group (Group N, n=70), who received an equal volume of saline in the same way.

Results

IV lidocaine reduced the total and maintenance propofol dose in Group L (p<0.001), with no significant effect on the induction dose. The incidence of intraoperative hypoxia (p=0.035), emergency airway management events (p=0.005), duration of gastroscopy (p<0.05), consciousness recovery time (p<0.001), and postoperative pain (p=0.009) were all reduced in Group L. Patient (p=0.025) and gastroscopist (p=0.031) satisfaction was higher in Group L. Intraoperative hemodynamic parameters, the respiratory rate, the incidence of sedation-related events and anesthesiologist satisfaction were similar between the two groups.

Conclusion

IV lidocaine can significantly reduce the amount of propofol, the incidence of hypoxia and postoperative pain during gastroscopy in elderly patients, with a higher patient and gastroscopist satisfaction.

The effectiveness of esketamine and propofol versus dezocine and propofol sedation during gastroscopy: A randomized controlled study

WHAT IS KNOWN AND OBJECTIVE

Propofol is widely used in painless gastroscopy. However, sedation with propofol alone might increase the risk of respiratory and circulatory complications. This randomized clinical study compares the efficacy and safety of esketamine or dezocine combined with intravenous (IV) propofol in patients undergoing gastroscopy.

METHODS

A total of 102 patients were enrolled in this study and randomized into two groups. All patients were adults aged 18-64 years who underwent upper gastrointestinal gastroscopy. Patients were randomly assigned to two groups to receive esketamine (0.3 mg/kg) combined with propofol (group E) or dezocine (0.05 mg/kg) combined with propofol (group D). In both groups, the drugs were administered intravenously. The primary outcome was the dose of propofol which provided a satisfactory sedative effect, both to the endoscopist and the patients. Secondary outcomes included recovery time, side effects (such as hypotension, nausea and vomiting and agitation), and the number of adverse circulatory and respiratory events.

RESULTS

Data of 83 patients were analysed in the present study. Dosage of propofol required in group E (1.44 mg/kg ± 0.67 mg/kg) was significantly lower compared with that in group D (2.12 mg/kg ± 0.37 mg/kg) (p < 0.0001). There was no statistically significant difference in recovery time, side effects, and the frequency of sedation-related adverse events between the two groups.

WHAT IS NEW AND CONCLUSION

The study indicates that intravenous injection of propofol and esmketamine is more effective for gastroscopy. Use of esketamine reduces the total amount of propofol required in ASA I-II patients undergoing gastroscopy compared with single use of dezocine. It also provides more stable hemodynamics, without affecting the recovery time and side effects such as respiratory and circulatory adverse events.

TRIAL REGISTRATION

The study was registered at the Chinese Clinical Trial Registry (www.chictr.org.cn; registration number: ChiCTR2100051814) on 05/10/2021.

Use of intravenous lidocaine for dose reduction of propofol in paediatric colonoscopy patients: a randomised placebo-controlled study

BACKGROUND

Propofol, a widely used sedative in endoscopic procedures, sometimes causes cardiopulmonary complications. Intravenous lidocaine can diminish visceral pain and decrease the dose of propofol. The purpose of this study was to assess the efficacy and safety of intravenous lidocaine in reducing propofol dosage during paediatric colonoscopy.

METHODS

Forty children who underwent colonoscopy were divided into two groups. Lidocaine hydrochloride (1.5 mg/kg induction and 2 mg/kg/h maintenance) was given intravenously to the lidocaine group, and the same amount of saline was given to the control group after they received lidocaine induction. Propofol initial plasma concentration of 5 μg/mL was targeted, and the procedure was performed after the bispectral index value reached 55. The primary outcome was propofol requirement.

RESULTS

The propofol requirement in the lidocaine group was decreased by 35.5% (128.6 ± 30.4 mg vs. 199.4 ± 57.6 mg; p < 0.001; 95%CI: - 100.60, - 41.02). The incidence of involuntary body movements was significantly lower in the lidocaine group (p = 0.028; OR = 0.17; 95%CI: 0.03, 0.92). The awakening time (p < 0.001; 95%CI: - 7.67, - 5.13) and recovery times (p < 0.001; 95%CI: - 7.45, - 4.35) were significantly lower in the lidocaine group. Pain was significantly less at 30 min and 60 min after the procedure in the lidocaine group (0 [0-4] vs. 3 [0-5], p < 0. 001; 0 [0-2] vs. 1 [0-3], p = 0.001). There was no difference in the incidence of bradycardia, hypotension, or hypoxia between the two groups.

CONCLUSIONS

For colonoscopy procedures in paediatric patients, intravenous lidocaine reduces the amount of propofol needed, provides better sedation and postprocedural pain management, as well as a reduction in recovery time.

TRIAL REGISTRATION

The trial was registered on November 6, 2020 at China Clinical Trials Registration Center ( www.chictr.org.cn ) ref.: ChiCTR 2,000,039,706.

Breathing variability during propofol/remifentanil procedural sedation with a single additional dose of midazolam or s-ketamine: a prospective observational study

Purpose

Regulation of spontaneous breathing is highly complex and may be influenced by drugs administered during the perioperative period. Because of their different pharmacological properties we hypothesized that midazolam and s-ketamine exert different effects on the variability of minute ventilation (MV), tidal volume (TV) and respiratory rate (RR).

Methods

Patients undergoing procedural sedation (PSA) with propofol and remifentanil received a single dose of midazolam (1–3 mg, n = 10) or s-ketamine (10–25 mg, n = 10). We used non-invasive impedance-based respiratory volume monitoring to record RR as well as changes in TV and MV. Variability of these three parameters was calculated as coefficients of variation.

Results

TV and MV decreased during PSA to a comparable extent in both groups, whereas there was no significant change in RR. In line with our hypothesis we observed marked differences in breathing variability. The variability of MV (– 47.5% ± 24.8%, p = 0.011), TV (– 42.1% ± 30.2%, p = 0.003), and RR (– 28.5% ± 29.3%, p = 0.011) was significantly reduced in patients receiving midazolam. In contrast, variability remained unchanged in patients receiving s-ketamine (MV + 16% ± 45.2%, p = 0.182; TV +12% ± 47.7%, p = 0.390; RR +39% ± 65.2%, p = 0.129). After termination of PSA breathing variables returned to baseline values.

Conclusions

While midazolam reduces respiratory variability in spontaneously breathing patients undergoing procedural sedation, s-ketamine preserves variability suggesting different effects on the regulation of spontaneous breathing.

Clinical Knowledge and Practice of "Ketofol" at University of Gondar Comprehensive Specialized Hospital

Background: Ketamine and propofol in a single syringe are reported to create an admixture used for balancing cardiorespiratory effects during induction of general anesthesia. This study aimed to assess the clinical practice and knowledge of “ketofol” among anesthesia providers.

Methods: A cross-sectional institutional-based study was conducted among anesthesia providers. Data abstracted format was prepared and distributed to senior anesthetists, junior anesthetist postgraduate students, and undergraduate students. The study was conducted from January 1, 2019, to January 30, 2019. Descriptive statistics and binary logistic regression were performed for frequency distribution and to determine the association, respectively.

Result: From a total of 133 participants included in the study, the majority, 88 (66.2%), were men and 75 (56.9%) had 0–2 years of experience. More than two-thirds of participants, 105 (78.9%), have never had a seminar or educational session about combined use. Lack of experience among 11 participants (8.3%) was one of the reasons for not using “ketofol” followed by lack of knowledge among three (2.3%) participants. The majority of participants, 112 (84.2%), prefer ketamine and propofol to be administered one right after the other with separate syringes and the ratio to be 1:2, 64 (48.2). There was no significant association observed between sociodemographic and other characteristics and the practice of “ketofol.”

Conclusion: In this study, nearly half of the participants rated their knowledge at the average level, and the study identifies that there is clinical knowledge and practice gap among anesthesia providers working in the University of Gondar Comprehensive Specialized Hospital (UOGCSH). Preparing educational sessions regarding “ketofol” for addressing identified barriers is among the recommendations forwarded to UOGCSH.

The median effective concentration of propofol with different doses of esketamine during gastrointestinal endoscopy in elderly patients: A randomized controlled trial

AIMS

Propofol may result in hypotension, bradycardia and loss of protective reflexes, especially in elderly patients, while esketamine, a N-methyl-D-aspartate receptor antagonist, has analgesic, anaesthetic and sympathomimetic properties and is known to cause less cardiorespiratory depression. We hypothesized that esketamine may reduce the median effective concentration (EC₅₀ ) of propofol and coadministration is less likely to produce hypotension during gastrointestinal endoscopy in elderly patients.

METHODS

Ninety elderly patients, aged 65-89 years, undergoing gastrointestinal endoscopy were randomly assigned into 3 groups: SK0 (control) group (0 mg/kg esketamine); SK0.25 group (0.25 mg/kg esketamine); and SK0.5 group (0.5 mg/kg esketamine). Anaesthesia was achieved by plasma target-controlled infusion of propofol with different bolus doses of esketamine. The EC₅₀ of propofol for gastrointestinal endoscopy was determined by using the up-and-down method of Dixon. The initial plasma target concentration is 2.5 μg/mL and the adjacent concentration gradient is 0.5 μg/mL. Cardiovascular variables were also measured.

RESULTS

Propofol EC₅₀ s and its 95% confidence interval for gastrointestinal endoscopy in elderly patients were 3.69 (2.59-4.78), 2.45 (1.85-3.05) and 1.71 (1.15-2.27) μg/mL in the SK0, SK0.25 and SK0.5 groups, respectively (P < .05). The average percent change from baseline mean arterial pressure was -19.7 (7.55), -15.2 (7.14) and -10.1 (6.73), in the SK0, SK0.25 and SK0.5 groups, respectively (P < .001).

CONCLUSION

Combination medication of propofol with esketamine reduced the propofol EC₅₀ during gastrointestinal endoscopy in elderly patients compared with administration of propofol without esketamine. Increasing doses of SK with propofol are less likely to produce hypotension with shorter recovery time.

Breathing variability-implications for anaesthesiology and intensive care

The respiratory system reacts instantaneously to intrinsic and extrinsic inputs. This adaptability results in significant fluctuations in breathing parameters, such as respiratory rate, tidal volume, and inspiratory flow profiles. Breathing variability is influenced by several conditions, including sleep, various pulmonary diseases, hypoxia, and anxiety disorders. Recent studies have suggested that weaning failure during mechanical ventilation may be predicted by low respiratory variability. This review describes methods for quantifying breathing variability, summarises the conditions and comorbidities that affect breathing variability, and discusses the potential implications of breathing variability for anaesthesia and intensive care.

Effect of Perioperative Ketamine on Postoperative Mood and Depression: A Review of the Literature

Introduction: Ketamine is being increasingly utilized in a variety of patient care settings, ranging from high acuity inpatient scenarios to the outpatient management of select mental health diagnoses. Postoperative patients are at an increased risk of developing a depressed state, and though ketamine's ability to improve mood is well documented in the literature, the relationship between perioperative ketamine and postoperative mood has not been fully elucidated. Areas covered: The purpose of this review was to determine ketamine's ability to improve mood and depression scores in the perioperative setting. A comprehensive literature review was conducted using PubMed, MEDLINE, Scopus, ProQuest, Web of Science, and CINAHL using the following search terminology: 'ketamine' AND 'perioperative' OR 'surgery' AND 'mood' OR 'depression.' Seven clinical trials are evaluated in this review. Expert opinion: As the use of ketamine continues to expand, clinicians must be cognizant of the fact that many of its desired effects are likely to overlap. Patients outside of the perioperative setting may benefit from using ketamine as an analgesic or sedative, as appropriate, to mitigate mood and depression. Ketamine, when administered as an anesthetic in the perioperative setting, seemingly has effect on postoperative mood and depression. Further studies that are sufficient.

Ketofol performance to reduce postoperative emergence agitation in children undergoing adenotonsillectomy

Background: Emergence agitation is a reformed state of mindfulness, which starts with a sudden form of anesthesia and progresses through the early repossession age. Thus, the purpose of this study is to evaluate 1:3 ketofol performance on children 3–15 years old undergoing adenotonsillectomy.Methods: A total of 60 children aged 3–15 years undergoing adenotonsillectomy were randomly allocated to receive low-dose ketamine 0.15 mg/kg followed by propofol 0.45 mg/kg i.v. ketofol (1:3) about 10 min before the end of surgery in comparison to 60 children aged 3–15 years who received only normal saline and dextrose. Anesthesia was induced and maintained with sevoflurane. Postoperative pain and EA were assessed with objective pain score (OPS) and the Pediatric Anesthesia Emergence Delirium (PAED) scale, respectively. EA was defined as a PAED 10 points. Recovery profile and postoperative complications were also recorded.Results: The incidence and severity of EA were found significantly lower in the ketofol group in comparison to the control group with a percentage of (13.33% vs 48.33%) (8% vs 15%) respectively (P < 0.05). Also, the time for interaction from anesthetic tainted to extubating in the ketofol set was significantly less than in the control group (P < 0.05). Interestingly, there are no opposing events such as nausea, laryngospasm, bronchospasm, hypotension, bradycardia, bleeding, or postoperative respiratory depression (respiratory rate: <16) were noticed in the ketofol supervision (P > 0.05). Moreover, the heart rate was meaningfully higher in the control group starting at the time of tracheal extubating in comparison to the children undergone ketofol (P < 0.05). Alert score and time from painkilling tainted till liberation from PACU showed substantial significant changes at ketofol set (P < 0.05).Conclusion: Ketofol (1:3) shows significant performance to reduce postoperative agitation in the children undergone adenotonsillectomy.

The effects of obesity on sedation-related outcomes of advanced endoscopic procedures

OBJECTIVE

Current literature covers limited data on the safety of sedation in advanced endoscopic procedures in obese patients. The present study aims to evaluate the association between obesity and the frequency of sedation-related complications in patients who were undergoing advanced endoscopic procedures.

METHODS

A retrospective chart analysis of 1172 consecutive patients, meeting the inclusion and exclusion criteria for this study and undergoing intravenous ketamine-propofol (ketofol) sedation for endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) procedures were evaluated. The patients were classified into three groups according to their body mass index (BMI) (kg/m2). Group I comprised patients with a BMI between 25 and 30, group II with a BMI between 30 and 35, and group III with a BMI between 35-40. The sedation-related outcomes in the form of adverse events, and airway interventions were compared between the groups.

RESULTS

For analysis, out of the 1172 available records, 289 patients had a BMI between 35-40 and were predominantly male patients. The total adverse events were more common in obese patients, with apnea (in 5.5% patients in group I, 5.7% in group II, 22.8% in group III p<0.000), oxygen desaturation (in 7.7% patients in group I, 9.4% in group II, and 27.7% in group III p<0.000), and airway obstruction (in 4.9% patients in group I, 5.4% in group II, 22.8% in group III, p<0.000). Moreover, the obese patients more frequently required airway interventions, including airway placement, suctioning and bag-mask ventilation.

CONCLUSION

Higher BMI was associated with an increased frequency of sedation-related complications. However, we concluded that ketofol sedation regimen could be used safely in obese patients during advanced endoscopic procedures by skilled anesthesia providers.

Comparison of ketamine-propofol mixture (ketofol) and midazolam-meperidine in endoscopic retrograde cholangiopancretography (ERCP) for oldest old patients

Background and aim: Endoscopic retrograde cholangiopancreatography (ERCP) requires moderate-to-deep conscious sedation. Combinations of ketamine and propofol (ketofol) and of midazolam and meperidine were analyzed using the bispectral index (BIS). There is no research on the use of ketofol on very elderly patients. The aim of this study is to use BIS and offer insight into the use and safety of ketofol sedation for oldest old patients undergoing ERCP.

Materials and methods: For the ERCP procedure, 168 patients aged 85+ years were enrolled in a 2-year retrospective single center study. Seventy-five patients received midazolam-meperidine (MM) sedation in 2016, while 75 patients received ketofol (KP) sedation in 2018.

The two groups were compared for patient data, procedure duration, Ramsay Sedation Score (RSS), heart rate (HR), blood pressure (BP), and pulse oximetry (SpO₂), BIS, facial pain score (FPS), time to achieve BIS, recovery time, and complications. The total amount of rescue medication was recorded.

Results: The two groups did not differ by patient data or procedure duration (p>0.05). Group KP had significantly higher systolic and diastolic BP, HR, and SpO₂ values and lower BIS scores than Group MM (p=0.0001). The two groups did not differ by time to achieve BIS scores (p>0.05). Group KP had significantly fewer complications and a shorter recovery time than Group MM (p<0.001).

Conclusion: Ketofol induced sedation results in more stable vital signs and fewer complications than the midazolam-meperidine sedation regimen during ERCP in oldest old patients, indicating that ketofol can be an alternative to midazolam-meperidine.

Safety and Efficacy of a Propofol and Ketamine Based Procedural Sedation Protocol in Children with Cerebral Palsy Undergoing Botulinum Toxin A Injections

BACKGROUND

Pediatric patients with cerebral palsy often undergo intramuscular botulinum toxin (BoNT-A) injections. These injections can be painful and may require procedural sedation. An ideal sedation protocol has yet to be elucidated.

OBJECTIVE

To investigate the safety and efficacy of a propofol and ketamine based sedation protocol in pediatric patients with cerebral palsy requiring BoNT-A injections.

DESIGN

Retrospective chart review.

SETTING

The sedations took place in a procedural sedation suite at a tertiary children's hospital from February 2013 through September 2017.

PATIENTS

164 patients with diagnoses of cerebral palsy undergoing propofol and ketamine based sedation for injections with botulinum toxin A.

METHODS

An initial bolus of 0.5 mg/kg ketamine followed by a 2 mg/kg bolus of propofol was administered with supplemental boluses of propofol as needed to achieve deep sedation during the intramuscular BoNT-A injections.

MAIN OUTCOME MEASUREMENTS

Propofol dosages, adverse events, serious adverse events, and sedation time parameters were reviewed.

RESULTS

345 sedations were successfully performed on 164 patients. The median total dose of propofol was 4.7 mg/kg (interquartile range [IQR]: 3.5, 6.3). Adverse events were encountered in 10.1% of procedures including hypoxemia responsive to supplemental oxygen (9.6%) and transient apnea (1.4%). The mean procedure time, recovery time, and total sedation time were 10, 11 and 33 minutes, respectively. With regard to patient variables, including age, weight, dose of propofol, sedation time, and Gross Motor Function Classification System classification, there was no association with increased incidence of adverse events.

CONCLUSION

Our sedation protocol of propofol and ketamine is safe and effective in children with cerebral palsy undergoing procedural sedation for intramuscular injections with BoNT-A. The adverse events encountered appeared to be related to airway and respiratory complications secondary to musculoskeletal deformities, emphasizing the importance of airway monitoring and management in these patients.

LEVEL

IV.

Opioid-induced respiratory depression in humans: a review of pharmacokinetic-pharmacodynamic modelling of reversal

BACKGROUND

Opioids are potent painkillers but come with serious adverse effects ranging from addiction to potentially lethal respiratory depression. A variety of drugs with separate mechanisms of action are available to prevent or reverse opioid-induced respiratory depression (OIRD).

METHODS

The authors reviewed human studies on reversal of OIRD using models that describe and predict the time course of pharmacokinetics (PK) and pharmacodynamics (PD) of opioids and reversal agents and link PK to PD.

RESULTS

The PKPD models differ in their basic structure to capture the specific pharmacological mechanisms by which reversal agents interact with opioid effects on breathing. The effect of naloxone, a competitive opioid receptor antagonist, is described by the combined effect-compartment receptor-binding model to quantify rate limitation at the level of drug distribution and receptor kinetics. The effects of reversal agents that act through non-opioidergic pathways, such as ketamine and the experimental drug GAL021, are described by physiological models, in which stimulants act at CO₂ chemosensitivity, CO₂-independent ventilation, or both. The PKPD analyses show that although all reversal strategies may be effective under certain circumstances, there are conditions at which reversal is less efficacious and sometimes even impossible.

CONCLUSIONS

Model-based drug development is needed to design an 'ideal' reversal agent-that is, one that is not influenced by opioid receptor kinetics, does not interfere with opioid analgesia, has a rapid onset of action with long-lasting effects, and is devoid of adverse effects.

Dexmedetomidine versus ketofol sedation for outpatient diagnostic transesophageal echocardiography: A randomized controlled study

Background

Moderate sedation is required for out-patient transesophageal echocardiography (TEE). Our objective was to compare the effect of Ketofol and dexmedetomidine for outpatient procedural sedation in diagnostic TEE with a hypothesis that Ketofol would be as effective as dexmedetomidine. Patients and.

Methods

Fifty adult patients of age group 18-60 years with atrial septal defect, rheumatic valvular heart disease undergoing diagnostic TEE in the outpatient echocardiography laboratory were randomized into two groups, group D and group KF. GROUP D: Dexmedetomidine infusion -200 μg in 20 ml normal saline. GROUP KF: Ketofol infusion: (ketamine: propofol, 1mg: 3 mg in 20 ml syringe). Loading dose of drug at 1ml/kg/hour IV till Ramsay sedation score (RSS) ≥ 3 achieved followed by maintenance infusion at 0.05 ml/kg/hour till end of procedure.

Results

The primary outcome - time to achieve Ramsay sedation score ≥ 3 was significantly lesser with Ketofol as compared to Dexmedetomidine 260[69] seconds vs 460 [137], (p value<0.05).

Conclusion

In out-patient setting, ketofol is favourable over dexmedetomidine for sedation regimen for diagnostic TEE as lesser time is taken to achieve optimal sedation with lesser hemodynamic perturbations, post procedure complications and better cardiologist satisfaction.

Anesthetic Pump Techniques Versus the Intermittent Bolus: What the Oral Surgeon Needs to Know

The most popular agents in use for office-based anesthesia are propofol, ketamine, and remifentanil, which have the desirable properties of rapid onset and short duration of action. A useful parameter in assessing these agents is the context-sensitive half-time. These anesthetic agents demonstrate relatively low, flat plots compared with older agents. For delivery of intravenous anesthetics, oral and maxillofacial surgeons have relied small incremental boluses with great success. However, relatively simple syringe infusion pumps can provide an even "smoother" anesthetic. This article familiarizes oral and maxillofacial surgeons with the advantages of infusion pumps and provides examples of their use.

Neurocognitive and behavioural performance of healthy volunteers receiving an increasing analgesic-range infusion of ketamine

BACKGROUND

The acute and delayed effect of analgesic-range doses of ketamine on neurocognitive and behavioural outcomes is understudied. Using a non-controlled open-labelled design, three (1-h duration) increasing intravenous (IV) ketamine infusions comprising (i) 30 mg bolus of ketamine + 8 mg/h IV infusion, (ii) 12 mg/h IV infusion and (iii) 20 mg/h infusion were administered to 20 participants (15 male, 5 female, mean age = 30.8 years). Whole-blood ketamine and norketamine concentrations were determined at each treatment step and post-infusion.

METHODS

The Cambridge Neuropsychological Test Automated Battery (CANTAB) was used to assess reaction/movement time (RTI, Simple and 5-Choice), visuospatial working memory (SWM), spatial planning (SOC) and subjective effects (visual analogue scale; VAS) during treatment and at post-treatment.

RESULTS

Significant main effects were reported for time (dose) on CANTAB RTI 5-Choice reaction (F(4,18) = 3.41, p = 0.029) and movement time (F(4,18) = 4.42, p = 0.011), SWM (F(4,18) = 4.19, p = 0.014) and SOC (F(4,18) = 4.13, p = 0.015), but not RTI Simple reaction or movement time. Post hoc analyses revealed dose-dependent effects for both RTI 5-Choice reaction and movement time (all p < 0.05). Post-treatment performance on all neurocognitive and behavioural tasks returned to baseline levels. Regression analyses revealed a weak positive linear association between SWM 'strategy' score (R² = 0.103, p < 0.001), all performance-based CANTAB VAS items (R² range 0.005-0.137, all p < 0.05) and ketamine blood concentrations.

DISCUSSION

The open-label, non-controlled trial design somewhat precludes the ability to adequately account for random treatment effects. Notwithstanding, these results suggest that analgesic doses of ketamine produce acute, selective, dose-dependent deficits in higher-order neurocognitive and behavioural domains.

Efficacy of Dexmedetomidine versus Ketofol for Sedation of Postoperative Mechanically Ventilated Patients with Obstructive Sleep Apnea

Patients with sleep apnea are prone to postoperative respiratory complications, requiring restriction of sedatives during perioperative care. We performed a prospective randomized study on 24 patients with obstructive sleep apnea (OSA) who underwent elective surgery under general anesthesia. The patients were equally divided into two groups: Group Dex: received dexmedetomidine loading dose 1 mcg/kg IV over 10 min followed by infusion of 0.2–0.7 mcg/kg/hr; Group KFL: received ketofol as an initial bolus dose 500 mcg/kg IV (ketamine/propofol 1 : 1) and maintenance dose of 5–10 mcg/kg/min. Sedation level (Ramsay sedation score), bispectral index (BIS), duration of mechanical ventilation, surgical intensive care unit (SICU) stay, and mean time to extubation were evaluated. Complications (hypotension, hypertension, bradycardia, postextubation apnea, respiratory depression, and desaturation) and number of patients requiring reintubation were recorded. There was a statistically significant difference between the two groups in BIS at the third hour only (Group DEX 63.00 ± 3.542 and Group KFL 66.42 ± 4.010, p value = 0.036). Duration of mechanical ventilation, SICU stay, and extubation time showed no statistically significant differences. No complications were recorded in both groups. Thus, dexmedetomidine was associated with lesser duration of mechanical ventilation and time to extubation than ketofol, but these differences were not statistically significant.

Post-Operative Cognitive Dysfunction: An exploration of the inflammatory hypothesis and novel therapies

Post-Operative Cognitive Dysfunction (POCD) is a highly prevalent condition with significant clinical, social and financial impacts for patients and their communities. The underlying pathophysiology is becoming increasingly understood, with the role of neuroinflammation and oxidative stress secondary to surgery and anaesthesia strongly implicated. This review aims to describe the putative mechanisms by which surgery-induced inflammation produces cognitive sequelae, with a focus on identifying potential novel therapies based upon their ability to modify these pathways.

Sedation with propofol during ERCP: is the combination with esketamine more effective and safer than with alfentanil? Study protocol for a randomized controlled trial

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is a gastrointestinal procedure that requires a relatively motionless patient during the intervention. Deep sedation by intravenous propofol combined with an opioid has recently become the preferred sedation technique. However, when high doses of propofol are used, side effects, namely respiratory depression, may occur. Esketamine has hypnotic, analgesic, and sympathomimetic effects. Our assumption is that a combination of propofol with esketamine reduces the dosage of individual drugs, thereby minimizing sedation side effects while keeping the same satisfaction level of patients and endoscopists.

Methods/design

The study will be performed as a randomized controlled multicenter trial. Patients undergoing ERCP, ≥ 18 years old, with American Society of Anesthesiologists (ASA) classification I–III will be randomized after written informed consent to group K (propofol/esketamine) or to group A (propofol/alfentanil). The primary outcome, reflecting effectiveness of sedation, is the total dose of propofol. Secondary outcome parameters are patients’ and endoscopists’ satisfaction with the procedure and the number of sedation-related pulmonary and cardiovascular events. Data on sedation-related events are collected by recording of oxygen saturation (SpO₂), respiratory rate (RR), end-tidal CO₂ (etCO₂), heart rate (HR), arrhythmias (electrocardiogram (ECG)), and non-invasive blood pressure (NIBP) measurements. Satisfaction parameters are collected by means of questionnaires before and after the procedure and on the following day.

Discussion

Esketamine is known for its effective anesthetic and analgesic effects maintaining spontaneous breathing and airway reflexes. Due to an increase in sympathetic tone, hypotension and cardiac depression is less common. Unfortunately esketamine is also known for its psychotomimetic effects. We aim to demonstrate that the combination of esketamine with propofol for sedation in patients subjected to ERCP interventions is nevertheless superior to a combination of propofol with an opioid.

Trial registration

Nederland’s Trial Register, NTR5486. Registered on 17 September 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2197-8) contains supplementary material, which is available to authorized users.

Moderate-to-deep sedation technique, using propofol and ketamine, allowing synchronised breathing for magnetic resonance high-intensity focused ultrasound (MR-HIFU) treatment for uterine fibroids: a pilot study

Background

Magnetic resonance high-intensity focused ultrasound (MR-HIFU) treatment for uterine fibroids is rapidly gaining popularity as a treatment modality. This procedure is generally uncomfortable, painful, and requires minimal or absence of movement and an MR-HIFU synchronised breathing pattern of the patient. Procedural sedation and analgesia protocols have become the standard practice in interventional radiology departments worldwide. The aim of this study was to explore if a sedation regimen with low-dose propofol and ketamine performed by trained non-medical sedation practitioners could result in relief of discomfort for the patient and in adequate working conditions for MR-HIFU treatment for uterine fibroids.

Methods

In this study, conducted from August 2013 until November 2014, 20 patients were subjected to MR-HIFU treatment of uterine fibroids. Patients were deeply sedated using intravenous propofol and esketamine according to a standardised hospital protocol to allow synchronisation of the breathing pattern to the MR-HIFU. The quality of sedation for MR-HIFU and complications were recorded and analysed. The side effects of the sedation technique, the propofol and esketamine consumption rate, the duration of recovery, and patient satisfaction after 24 h were examined.

Results

A total of 20 female patients (mean age 42.4 [range 32–53] years) were enrolled. Mean propofol/esketamine dose was 1309 mg/39.5 mg (range 692–1970 mg/ 23.6–87.9 mg). Mean procedure time was 269 min (range 140–295 min). Application of the sedation protocol resulted in a regular breathing pattern, which could be synchronised with the MR-HIFU procedures without delay. The required treatment was completed in all cases. There were no major adverse events. Hypoxemia (oxygen desaturation <92%) and hallucinations were not observed.

Conclusions

The use of a specific combination of IV propofol and esketamine for procedural sedation and analgesia reduced the discomfort and pain during MR-guided HIFU treatments of uterine fibroids. The resulting regular breathing pattern allowed for easy synchronisation of the MR-HIFU procedure. Based on our results, esketamine and propofol sedation performed by trained non-medical sedation practitioners is feasible and safe, has a low risk of major adverse events, and has a short recovery time, avoiding a session of general anaesthesia.

Electronic supplementary material

The online version of this article (doi:10.1186/s40349-017-0088-9) contains supplementary material, which is available to authorized users.

The effect of ketamine on hypoventilation during deep sedation with midazolam and propofol: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Hypoventilation is a major cause of morbidity and mortality in patients having procedures under sedation. Few clinical strategies have been evaluated to reduce intraoperative hypoventilation during surgical procedures under deep sedation.

OBJECTIVE

The primary objective of this investigation was to examine the effect of ketamine on hypoventilation in patients receiving deep sedation for surgery with midazolam and propofol.

DESIGN

The study was a randomised, placebo-controlled, double-blind clinical trial.

SETTING

Intraoperative.

PATIENTS

Healthy women undergoing breast surgery.

INTERVENTION

Randomised to receive ketamine (0.5 mg kg bolus, followed by an infusion of 1.5 μg kg min) or isotonic saline.

MAIN OUTCOME MEASURE

Duration of hypercapnia measured continuously with a transcutaneous carbon dioxide (TCO2) monitor.

RESULTS

Fifty-four participants were recruited. Patient and surgical characteristics were similar between the study groups. The median percentage of the sedation time with TCO2 more than 6.7 kPa in participants in the ketamine group, 1.2% (95% confidence interval, CI, 0 to 83), was less than that in the isotonic saline group (65%, 95% CI, 0 to 88; P = 0.01). Severe hypoventilation (TCO2 >8.0 kPa) was also less in the ketamine group, median 0% (95% CI, 0 to 11.7) compared with 28% (95% CI, 0 to 79.3; P = 0.0002) for the isotonic saline group. The ketamine group required less airway manoeuvres (chin lift) to keep the SaO2 greater than 95% median (95% CI) [0 (0 to 3) compared with 3 (0 to 16) in the isotonic saline group] (P = 0.004).

CONCLUSION

Ketamine decreased the duration and severity of hypercapnia in patients undergoing deep sedation with propofol. The addition of ketamine may reduce hypoventilation and adverse effects in patients having procedures under sedation.

TRIAL REGISTRATION

clinicaltrials.gov identifier: NCT01535976.

A comparative study on monitored anesthesia care

Aim:

The aim of this study is to compare the effectiveness, hemodynamic changes and duration of sedation and analgesia between combinations of fortwin-phenergan-midazolam (FPM) and ketamine - midazolam (KM) along with local anesthesia for the surgeries done under the umbrella of monitored anesthesia care.

Materials and Methods:

A total of 50 patients undergoing surgeries as tympanoplasty, septoplasty, lip repair, dacrocystectomy and cataract under local anesthesia, randomly received either intravenous (IV) fortwin 0.3 mg/kg over 1 min followed by IV midazolam 0.04 mg/kg plus IV phenergan 12.5 mg (Group FPM) or IV ketamine 0.3 mg/kg over 1 min plus IV midazolam 0.04 mg/kg (Group KM). Sedation was titrated to Ramsay sedation score (RSS) of 3. Patients’ mean arterial pressure (MAP), heart rate (HR), saturation peripheral pulse, duration of sedation and need for intraoperative rescue sedation/analgesic were recorded and compared. Satisfaction of patients (using a 1-7 point Likert verbal rating scale) and readiness for discharge towards (time to Aldrete score of 10) were also determined.

Result:

Group KM had significant rise in HR (20-25%) and MAP (25-30%) from 30 min after the bolus dose given until the end of the surgery in contrast to Group FPM. The target sedation level (RSS ≥ 3) was higher in Group FPM (n = 23 [92%]) as compared with Group KM (n = 12 [48%]). Time until need for rescue sedation was 66.96 ± 17.19 min in FPM and 32.80 ± 8.90 min in KM group. The patient satisfaction (Likert scale) is more with the FPM group (6.12 ± 0.83 vs. 4.40 ± 1.20).

Conclusion:

We found that the combination of FPM is superior to the KM combination as per the hemodynamic changes, duration of analgesia, patients’ satisfaction and efficacy of the drugs are concerned.

A clinical comparison of ketofol (ketamine and propofol admixture) versus propofol as an induction agent on quality of laryngeal mask airway insertion and hemodynamic stability in children

Background:

In spite of being the preferred induction agent for LMA insertion, propofol has many undesirable side effects including dose-related cardiorespiratory depression and local pain at injection site. Ketofol as a novel induction agent has been introduced recently with comparable efficacy and improved hemodynamic control

Objective:

To investigate ketofol as a suitable induction agent alternative to propofol for insertion of LMA in children considering insertion conditions, hemodynamic stability, local pain at injection site, and recovery.

Materials and Methods:

In this randomized, double-blind study, 100 children were randomly assigned into two groups of 50 patients each in which induction was performed with either propofol or ketofol. Providers were given one 20 ml syringe [represent either 2 mg/kg of propofol (P group) or 0.75 mg/kg of ketamine and 1.5 mg/kg of propofol (KP group)] and one 10 ml syringe for rescue if needed [represent 1 mg/kg of propofol (P group) or 0.25 mg/kg of ketamine and 0.5 mg/kg of propofol (KP group)]. After monitoring with bispectral index (BIS), general anesthesia was induced by infusion with a syringe perfuser at a constant rate of 250 ml/h with either of the two agents till the BIS values decreased to 40. Mean arterial pressure (MAP), heart rate (HR) were measured every 30 seconds up to 5 minutes after LMA placement. The time till BIS values decreased to 40 was measured. All children were evaluated for incidence of apnea, pain on injection, jaw relaxation, conditions for LMA insertion, and complications such as muscle rigidity, hallucinations, and excessive secretions.

Results:

Induction time (time to reach BIS of 40) was faster in the KP group (150 ± 23.5 seconds) than in the P group (205 ± 37.4 seconds). The incidence of injection pain was significantly lower in the KP group (10%) than in the P group (80%). Excellent jaw relaxation and full mouth opening were higher in the KP group [45 patients (90%)] than in the P group [38 patients (76%)]. Excellent LMA insertion conditions were observed in 45 patients (90%) in the KP group and 38 patients (76%) in the P group. The KP group showed preserved hemodynamic stability (mean blood pressure, heart rate) with less incidence and duration of apnea compared to the P group.

Conclusion:

ketofol is a safe and effective alternative induction agent for LMA insertion in children with rapid onset of action and lower incidence of injection pain. It provided better LMA insertion conditions, improved hemodynamic stability with less prolonged apnea when compared with propofol.

The Comparison of Infusion of Two Different Sedation Regimens with Propofol and Ketamine Combination During Plastic and Reconstructive Surgery

OBJECTIVE

Anesthetic agents are often combined to enhance their therapeutic effects while minimizing adverse events. The aim of this study was to evaluate the effects of two different sedation regimens of ketamine and propofol combination via infusion on perioperative variables in patients who underwent plastic and reconstructive surgery.

METHODS

This randomized double-blind clinical trial was done on 80 patients who were randomized to two groups; group 1 (n = 40) received a 2:1 mixture of 9 mg/ml propofol and 4.5 mg/ml ketamine, and group 2 (n = 40) received a 4:1 mixture of 9 mg/ml propofol and 2.25 mg/ml ketamine. After premedication and before local anesthetic injection, the infusion of mixtures was adjusted to attain the Ramsay sedation scores of 5 in both groups. We recorded induction time, sedation efficacy, cardiovascular and respiratory events, recovery time, and incidence of adverse events during and after the procedure.

RESULTS

The mean of volume infusion of mixtures in the beginning of the procedure was higher in group 2 (3.2 ± 1. 2 ml) than in group 1 (2.4 ± 0.8 ml) (p < 0.001). The induction time for sedation was 2.8 ± 0.8 min and 2.6 ± 0.4 min in group 1 and group 2, respectively (p = 0. 92). The number of oversedated patients was greater in group 2 compared to group 1 but not statistically significant (p = 0. 80). The sedation efficacy was similar between the two groups. The hemodynamic changes during the procedure were greater in group 2 compared to group 1 (p = 0. 001). The recovery time was not significantly different between the two groups (p = 0.43). The mean pain score in the recovery room was lower in group 1 than group 2 (1.2 ± 0.8 vs 2.8 ± 1.8, p = 0. 01). Moreover, 4 (10 %) patients in group 1 and 10 (25 %) patients in group 2 needed opioid administration (p = 0. 02). Other postoperative adverse events were similar between the two groups.

CONCLUSION

We recommend the use of a 2:1 combination of propofol-ketamine, because it reduced the rescue propofol requirement and consequently produced lower cardiovascular and respiratory depression effects and also less postoperative pain.

A randomized trial evaluating low doses of propofol infusion after intravenous ketamine for ambulatory pediatric magnetic resonance imaging

Objective:

Our study compared the discharge time after pediatric magnetic resonance imaging (MRI) following sedation with propofol infusion dose of 100, 75 and 50 mcg/kg/min given after a bolus dose of ketamine and propofol.

Materials and Methods:

One hundred children of American Society of Anesthesiologists status 1/2, aged 6 months to 8 years, scheduled for elective MRI were enrolled and randomized to three groups to receive propofol infusion of 100, 75 or 50 mcg/kg/min (Groups A, B, and C, respectively). After premedicating children with midazolam 0.05 mg/kg intravenous (i.v.), sedation was induced with bolus dose of ketamine and propofol (1 mg/kg each) and the propofol infusion was connected. During the scan, heart rate, noninvasive blood pressure, respiratory rate, and oxygen saturation were monitored.

Results:

The primary outcome that is, discharge time was shortest for Group C (44.06 ± 18.64 min) and longest for Group A (60.00 ± 18.66 min), the difference being statistically and clinically significant. The secondary outcomes that is, additional propofol boluses, scan quality and awakening time were comparable for the three groups. The systolic blood pressure at 20, 25 and 30 min was significantly lower in Groups A and B compared with Group C. The incidence of sedation related adverse events was highest in Group A and least in Group C.

Conclusion:

After a bolus dose of ketamine and propofol (1 mg/kg each), propofol infusion of 50 mcg/kg/min provided sedation with shortest discharge time for MRI in children premedicated with midazolam 0.05 mg/kg i.v. It also enabled stable hemodynamics with less adverse events.

A clinical pathway for total shoulder arthroplasty-a pilot study

BACKGROUND

Appropriate pain management after total shoulder arthroplasty (TSA) facilitates rehabilitation and may improve clinical outcomes.

QUESTIONS/PURPOSES

This prospective, observational study evaluated a multimodal analgesia clinical pathway for TSA.

METHODS

Ten TSA patients received an interscalene nerve block (25 cm(3) 0.375% ropivacaine) with intraoperative general anesthesia. Postoperative analgesia included regularly scheduled non-opioid analgesics (meloxicam, acetaminophen, and pregabalin) and opioids on demand (oral oxycodone and intravenous patient-controlled hydromorphone). Patients were evaluated twice daily to assess pain, anterior deltoid strength, handgrip strength, and sensory function.

RESULTS

The nerve block lasted an average of 18 h. Patients had minimal pain after surgery; 0 (median score on a 0-10 scale) in the Post-Anesthesia Care Unit (PACU) but increased on postoperative day (POD) 1 to 2.3 (0.0, 3.8; median (25%, 75%)) at rest and 3.8 (2.1, 6.1) with movement. Half of the patients activated the patient-controlled analgesia four or fewer times in the first 24 h after surgery. Operative anterior deltoid strength was 0 in the PACU but returned to 68% by POD 1. Operative hand strength was 0 (median) in the PACU, but the third quartile (75%) had normalized strength 49% of preoperative value.

CONCLUSIONS

Patients did well with this multimodal analgesic protocol. Pain scores were low, half of the patients used little or no intravenous opiate, and some patients had good handgrip strength. Future research can focus on increasing duration of analgesia from the nerve block, minimizing motor block, lowering pain scores, and avoiding intravenous opioids.

A comparison of ketamine-midazolam and ketamine-propofol combinations used for sedation in the endobronchial ultrasound-guided transbronchial needle aspiration: a prospective, single-blind, randomized study

OBJECTIVE

We aimed to compare the effectiveness and safety of ketamine-midazolam and ketamine-propofol combinations for procedural sedation in endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA).

METHODS

Sixty patients who were undergoing EBUS-TBNA were included in this study. Patients were randomly divided into two groups. Group 1 was given 0.25 mg/kg intravenous (iv) ketamine, 2 min later than 0.05 mg/kg iv midazolam. Group 2 received 0.125 mg/kg ketamine-propofol mixture (ketofol), 2 min subsequent to injection of 0.25 mg/kg each. Sedation was maintained with additional doses of ketamine 0.25 mg/kg, and ketofol 0.125 mg/kg each in Group 1 and Group 2, respectively. Blood pressure, heart rate (HR), peripheral oxygen saturation, respiratory rate (RR), Ramsay Sedation Score (RSS), and severity of cough were recorded prior to and after administration of sedation agent in the beginning of fiberoptic bronchoscopy (FOB) and every 5 min of the procedure. The consumption of the agents, the satisfactions of the bronchoscopist and the patients, and the recovery time were also recorded.

RESULTS

HR in the 10(th) min and RSS value in the 35(th) min of induction in Group 1 were higher than the other group (P<0.05). The recovery time in Group 1 was statistically longer than Group 2 (P<0.05). There was no statistically significant difference between groups with respect to other parameters (P>0.05).

CONCLUSIONS

It was concluded that both ketamine-midazolam and ketamine-propofol combinations for sedation during EBUS-TBNA were similarly effective and safe without remarkable side effects.

Comparison of Propofol and Ketamine versus Propofol and Fentanyl for Puerperal Sterilization, A Randomized Clinical Trial

BACKGROUND

Puerperal sterilization requires a rapid recovery of the mother so that she can take care of her child. Propofol with fentanyl (PF) is an option, but is associated with intraoperative hypotension, respiratory depression and an unsatisfactory postoperative recovery profile. Propofol with ketamine (PK) appears to be an alternative in terms of haemodynamic stability and analgesia.

MATERIALS AND METHODS

This randomized clinical trial involved 60 patients who were scheduled to undergo puerperal sterilization, who belonged to American society of anaesthesiologists (ASA) physical status 1. Patients were randomly allocated to receive either ketamine - propofol infusion in a concentration of 8mg/ml each (group PK) or fentanyl 2μg/kg intravenously, followed by an infusion of propofol in a concentration of 8mg/ml (group PF). In both the groups, the infusion was started at 300ml/hr till patient lost consciousness. Subsequently, the rate was set at 1.5ml/kg/hr for group PF and at 0.75ml/kg/hr for group PK. After the initial 10 minutes, the infusion rate was reduced to 1ml/kg/hr for group PF and to 0.5ml/kg/hr for group PK. Blood pressure and saturation were the primary outcomes which were measured.

RESULTS

Patients from group PF recorded a significant drop in the systolic blood pressure from the 5(th) minute, in diastolic pressure from the 10(th) minute and transient oxygen desaturation, as compared to group PK. Patients in group PK had adequate surgical conditions and better recovery profiles in terms of pain and sedation.

CONCLUSION

The combination of ketamine and propofol is a safe and possibly superior alternative to propofol - fentanyl combination in patients who undergo puerperal sterilization, in terms of haemodynamic stability and respiratory depression.

Immediate ketamine treatment does not prevent posttraumatic stress responses in an animal model for PTSD

Clinical studies suggest that administration of ketamine hydrochloride-an antagonist at the N-methyl-d-aspartate ionophore-provides short-term amelioration for depressive symptoms. The effects of a brief course of ketamine given immediately following exposure to psychogenic stress on the behavioral stress responses were assessed in an animal model of posttraumatic stress disorder. Animals exposed to stress were treated 1h later with ketamine (0.5, 5, and 15 mg/kg) or vehicle for three days (N = 107). Outcome measures included behavior in the elevated plus maze (EPM) and acoustic startle response (ASR) tests 30 days after initial exposure and freezing behavior upon exposure to a trauma-cue on day 31. Pre-set cut-off behavioral criteria classified exposed animals according to their EPM and ASR response-patterns into "extreme," "minimal," or "partial" behavioral response for analysis of prevalence rates of "PTSD-like behavior." Circulating corticosterone levels were assessed 20 min after injection of ketamine in exposed and unexposed animals (N = 62). The dexamethasone suppression test was used to assess negative feedback inhibition of the HPA axis. Prevalence rates of extremely-, partially-, or minimally-disrupted behavior demonstrated that ketamine administered immediately following stress exposure was ineffective in alleviating "PTSD-like behavior" at day 30 after exposure. Administration of ketamine was associated with increase in freezing behavior after exposure to a trauma-cue on day 31. Corticosterone levels were significantly suppressed by ketamine only in the exposed animals. Administration of ketamine immediately following trauma-exposure may not only be ineffective but actually detrimental in the long term. A disruption of the post-stress HPA-response has been raised as a contributing factor.

Effects of anesthetics, sedatives, and opioids on ventilatory control

This article provides a comprehensive, up to date summary of the effects of volatile, gaseous, and intravenous anesthetics and opioid agonists on ventilatory control. Emphasis is placed on data from human studies. Further mechanistic insights are provided by in vivo and in vitro data from other mammalian species. The focus is on the effects of clinically relevant agonist concentrations and studies using pharmacological, that is, supraclinical agonist concentrations are de-emphasized or excluded.

Hemodynamic responses with different dose of ketamine and propofol in day care gynecological surgeries

BACKGROUND

Day care gynaecological surgeries mandate use of hemodynamically stable combination of commonly used intravenous agents, propofol & ketamine. Hence we proposed to evaluate the hemodynamic profile of different dose combination of propofol & ketamine as induction agents in ambulatory gynecological surgeries.

MATERIAL & METHODS

Thirty adult patients scheduled for day care gynecological surgeries were randomly divided into five Groups. Group I received inj. propofol 2mg/kg i.v + inj. Normal saline (NS); Group II received ketamine 2mg/kg i.v + inj. NS; Group III was given inj. Propofol 2mg/kg i.v followed by inj. Ketamine 1 mg/kg i.v.; Group IV received inj. Ketamine 2 mg/kg i.v followed by inj. propofol 1 mg/kg i.v; Group V received combination of inj. Propofol 1 mg/kg i.v and inj. Ketamine 1 mg/kg i.v. After administration of the drug, non invasive systolic, diastolic and mean arterial pressures, heart rate, respiratory rate, arterial oxygen saturation and ECG were recorded every minute for five minutes.

RESULTS

Statistically significant hemodynamic alterations were observed in Group I & II, with Group I having the highest incidence of apnea (23.3%). No significant changes in hemodynamics were seen in Group V.

CONCLUSION

We conclude that the combination of 1mg Propofol and 1mg ketamine produced better hemodynamic stability in comparison to other Groups.

Lidocaine administration before tracheal extubation cannot reduce post-operative cognition disorders in elderly patients

Background:

Cognitive dysfunction after surgery is common in elderly patients. Many factors such as anesthetic drugs can cause complication in this surgery. Lidocaine is one of the drugs commonly used during anesthesia. So, we designed this study to find out cognitive effect of lidocaine in elderly patients undergoing non-cardiac surgeries.

Materials and Methods:

In this double-blinded clinical trial, we enrolled 70 patients older than 65 years age undergoing urologic or orthopedic surgeries, were divided in two groups. Patients randomly received intravenous lidocaine (1.5 mg/kg) or normal saline in the same volume immediately before extubation. Mini mental state examination (MMSE) test was used to evaluate cognitive state at discharge time, 6 and 24 h after surgery.

Results:

Mean MMSE scores at the time of discharge from recovery room in lidocaine and saline groups were 22.4 ± 4.5 vs. 22.1 ± 4.4, P = 0.755, respectively. It was significantly lower than MMSE before surgery, 6 and 24 h after the operation. The mean MMSE scores and frequency distribution of intensity of cognitive impairments were not significantly different between two groups at different times.

Conclusion:

Bolus intravenous lidocaine before extubation, did not affect cognitive states in elders undergoing non-cardiac surgery. Effect of lidocaine on cardiac surgeries is clear, but in non-cardiac surgeries, lidocaine has no clinical effects. So, more studies with different doses of lidocaine and different assessment methods are recommended.

An effective dose of ketamine for eliminating pain during injection of propofol: a dose response study

BACKGROUND AND PURPOSE

Ketamine can completely eliminate pain associated with propofol injection. However, the effective dose of ketamine to eliminate propofol injection pain has not been determined. The purpose of this study was to determine the effective dose of ketamine needed to eliminate pain in 50% and 95% of patients (ED50 and ED95, respectively) during propofol injections.

METHODS

This study was conducted in a double-blinded fashion and included 50 patients scheduled for elective gynecological laparoscopy under general anesthesia. The initial dose of ketamine used in the first patient was 0.25mg/kg. The dosing modifications were in increments or decrements of 0.025 mg/kg. Ketamine was administered 15 seconds before injecting propofol (2.5mg/kg), which was injected at a rate of 1mL/s. Patients were asked to rate their pain during propofol injection every 5s econds using a 0-3 pain scale. The highest pain score was recorded. The ED50, ED95 and 95% confidence intervals (CI) were determined by probit analyses.

RESULTS

The dose of ketamine ranged from 0.175 to 0.275 mg/kg. The ED50 and ED95 of ketamine for eliminating pain during propofol injection were 0.227 mg/kg and 0.283 mg/kg, respectively (95%CI: 0.211-0.243 mg/kg and 0.26-0.364 mg/kg, respectively).

CONCLUSION

Ketamine at an approximate dose of 0.3mg/kg was effective in eliminating pain during propofol injection.

Evaluation of a ketamine-propofol drug combination with or without dexmedetomidine for intravenous anesthesia in cats undergoing ovariectomy

OBJECTIVE

To evaluate the use of a ketamine-propofol combination, with or without dexmedetomidine, in cats undergoing ovariectomy and to assess Heinz body formation following administration of these drugs.

DESIGN

Randomized clinical trial.

ANIMALS

15 client-owned female cats.

PROCEDURES

Anesthesia was induced with a ketamine (2.0 mg/kg [0.91 mg/lb])-propofol (2.0 mg/kg) combination with (n = 7) or without (8) dexmedetomidine (0.003 mg/kg [0.0013 mg/lb]) and was maintained via continuous IV infusion of a 1:1 ketamine-propofol combination (administration rate for each drug, 10.0 mg/kg/h [4.54 mg/lb/h]). Cats underwent ovariectomy; duration of infusion was 25 minutes. Physiologic variables were measured at predetermined time points. Heinz bodies were quantified via examination of blood smears. Numeric scales were used to assess quality of recovery, degree of sedation, and signs of pain after surgery.

RESULTS

The ketamine-propofol group had a significantly higher mean heart rate at several time points during drug infusion, a significantly shorter time from the end of infusion to extubation (7 vs 29 minutes), and significantly lower sedation scores for the first hour after surgery than did the ketamine-propofol-dexmedetomidine group. Other variables were similar between groups; recovery was smooth, and anesthesia and postoperative analgesia were deemed adequate for all cats. The number of RBCs with Heinz bodies was not increased after surgery, compared with values immediately after anesthetic induction.

CONCLUSIONS AND CLINICAL RELEVANCE

Total IV anesthesia with a ketamine-propofol combination, with or without dexmedetomidine, appeared to be effective in healthy cats. These short-term infusions produced smooth recovery and adequate analgesia during the postoperative period.

Intravenous infusion of ketamine-propofol can be an alternative to intravenous infusion of fentanyl-propofol for deep sedation and analgesia in paediatric patients undergoing emergency short surgical procedures

Background:

Paediatric patients often present with different painful conditions that require immediate surgical interventions. Despite a plethora of articles on the ketamine–propofol combination, comprehensive evidence regarding the suitable sedoanalgesia regime is lacking due to heterogeneity in study designs.

Methods:

This prospective, randomized, double-blind, active–controlled trial was conducted in 100 children, of age 3–14 years, American Society of Anesthesiologist physical status IE-IIE, posted for emergency short surgical procedures. Patients were randomly allocated to receive either 2 mL of normal saline (pre-induction) plus calculated volume of drug from the 11 mL of ketamine–propofol solution for induction (group PK, n=50) or fentanyl 1.5 μg/kg diluted to 2 mL with normal saline (pre-induction) plus calculated volume of drug from the 11 mL of propofol solution for induction (group PF, n=50). In both the groups, the initial bolus propofol 1 mg/kg i.v. (assuming the syringes contained only propofol, for simplicity) was followed by adjusted infusion to achieve a Ramsay Sedation Scale score of six. Mean arterial pressure (MAP) was the primary outcome measurement.

Results:

Data from 48 patients in group PK and 44 patients in group PF were available for analysis. Hypotension was found in seven patients (14.6%) in group PK compared with 17 (38.6%) patients in group PF (P=0.009). Intraoperative MAP was significantly lower in group PF than group PK when compared with baseline.

Conclusion:

The combination of low-dose ketamine and propofol is more effective and a safer sedoanalgesia regimen than the propofol–fentanyl combination in paediatric emergency short surgical procedures in terms of haemodynamic stability and lesser incidence of apnoea.