A randomized controlled trial of ketamine/propofol versus propofol alone for emergency department procedural sedation

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.

[Ketamine-propofol sedation in circumcision]

BACKGROUND AND OBJECTIVE

to compare the therapeutic effects of ketamine alone or ketamine plus propofol on analgesia, sedation, recovery time, side effects in premedicated children with midazolam-ketamine-atropin who are prepared circumcision operation.

METHODS

60 American Society of Anaesthesiologists physical status I-II children, aged between 3 and 9 years, undergoing circumcision operations under sedation were recruited according to a randomize and double-blind institutional review board-approved protocol. Patients were randomized into two groups via sealed envelope assignment. Both groups were administered a mixture of midazolam 0.05mg/kg+ketamine 3mg/kg+atropine 0.02mg/kg intramuscularly in the presence of parents in the pre-operative holding area. Patients were induced with propofol-ketamine in Group I or ketamine alone in Group II.

RESULTS

in the between-group comparisons, age, weight, initial systolic blood pressure, a difference in terms of the initial pulse rate was observed (p>0.050). Initial diastolic blood pressure and subsequent serial measurements of 5, 10, 15, 20thmin, systolic blood pressure, diastolic blood pressure and pulse rate in ketamine group were significantly higher (p<0.050).

CONCLUSION

propofol-ketamine (Ketofol) provided better sedation quality and hemodynamy than ketamine alone in pediatric circumcision operations. We did not observe significant complications during sedation in these two groups. Therefore, ketofol appears to be an effective and safe sedation method for circumcision operation.

Ketofol dosing simulations for procedural sedation

BACKGROUND

Propofol mixed with racemic ketamine (or "ketofol") is popular for short procedural sedation and analgesia, yet the optimal combination is unknown. We aimed to determine a ketofol dosing regimen for short procedural sedation and analgesia of 5- to 20-minute duration in healthy patients (2-20 y).

METHODS

Pharmacokinetic-pharmacodynamic parameters were used to simulate drug concentration and effect profiles over time for different ketamine-to-propofol ratios (1:1-1:10). The target effect was a Children's Hospital of Wisconsin Sedation Scale score of less than 2. Combined effects were additive, with a propofol EC50 of 1.54 μg/mL (concentration required to produce hypnosis in 50% of patients), a ketamine EC50 of 0.44 μg/mL, and a slope of 5.3. Emergence threshold concentrations for propofol were 2.0 μg/mL in children and 1.8 μg/mL in adults as well as 0.5 μg/mL for ketamine (children and adults). The EC50 for propofol antiemesis was 0.343 μg/mL.

RESULTS

A ketamine-to-propofol ratio of 1:3 was the best combination for intermittent dosing, achieving a rapid onset of a Children's Hospital of Wisconsin Sedation Scale score of less than 2 within 1 minute and a time to emergence of 9 to 19 minutes in all ages after a 10-minute sedation. The optimal ketofol dosing in children (2-11 y) was 0.1 mL/kg initially followed by 0.05 mL/kg at 2 minutes and then 0.025 mL/kg for the subsequent doses. The adults (12-20 y) received 0.05 mL/kg of ketofol initially followed by 0.025 mL/kg for the subsequent doses. These regimens maintain a propofol antiemesis for 30 to 40 minutes after the last dose.

CONCLUSIONS

We suggest an optimal ratio of racemic ketamine to propofol of 1:3 for boluses during short procedures (5-20 minutes). A short ketofol infusion, ratio 1:4, is a suitable alternative to intermittent boluses. Ratios greater than 1:3 result in delayed recovery after 20 minutes.

Ketamine-propofol sedation in circumcision

BACKGROUND AND OBJECTIVE

To compare the therapeutic effects of ketamine alone or ketamine plus propofol on analgesia, sedation, recovery time, side effects in premedicated children with midazolam-ketamine-atropin who are prepared circumcision operation.

METHODS

60 American Society of Anaesthesiologists physical status I-II children, aged between 3 and 9 years, undergoing circumcision operations under sedation were recruited according to a randomize and double-blind institutional review board-approved protocol. Patients were randomized into two groups via sealed envelope assignment. Both groups were administered a mixture of midazolam 0.05mg/kg+ketamine 3mg/kg+atropine 0.02mg/kg intramuscularly in the presence of parents in the pre-operative holding area. Patients were induced with propofol-ketamine in Group I or ketamine alone in Group II.

RESULTS

In the between-group comparisons, age, weight, initial systolic blood pressure, a difference in terms of the initial pulse rate was observed (p>0.050). Initial diastolic blood pressure and subsequent serial measurements of 5, 10, 15, 20thmin, systolic blood pressure, diastolic blood pressure and pulse rate in ketamine group were significantly higher (p<0.050).

CONCLUSION

Propofol-ketamine (Ketofol) provided better sedation quality and hemodynamy than ketamine alone in pediatric circumcision operations. We did not observe significant complications during sedation in these two groups. Therefore, ketofol appears to be an effective and safe sedation method for circumcision operation.

An update on pediatric hospital-based sedation

PURPOSE OF REVIEW

The need for sedation for procedures performed outside the operating room has increased dramatically, and pediatric procedural sedation (PPS) is increasingly performed by practitioners who are not anesthesiologists. With 'sedationists' emerging from various specialties, there are differences in practice and guidelines with regards to presedation assessment, targeted depths of sedation, monitoring requirements, and the training required. Our aim is to identify some of the recent advances in PPS and to describe progress towards greater standardization of practice.

RECENT FINDINGS

Several studies report attempts to optimize the efficacy of specific pharmaceuticals used in PPS. Ketamine, a dissociative agent, functions uniquely and requires its own sedation practice guidelines. Utilizing less invasive administration of sedation via transmucosal and inhaled routes is gaining popularity. Additionally, replacing subjective measurement of depths of the sedation continuum and the nonstandardized definitions of adverse events with alternatives based on physiological parameters and/or required rescue interventions is underway. Finally, the use of presedation family-centered counseling and adjuncts that provide visual and auditory distraction are enhancing pharmaceutical methods.

SUMMARY

Further multispecialty collaboration and formation of greater consensus with regards to sedation practice are essential to the development of universal guidelines that optimize patient care.

Propofol for Procedural Sedation in the Emergency Department: A Qualitative Systematic Review

OBJECTIVE:

To evaluate the efficacy and safety of propofol compared to other agents for procedural sedation of adults in the emergency department (ED) and to review the use of opioids in conjunction with propofol for procedural sedation in the ED.

DATA SOURCES:

PubMed (1949-December 2012) and EMBASE (1980-December 2012) were searched using combinations of the following search terms: (procedural sedation or conscious sedation [MESH]) and propofol. A manual search of references was also performed.

STUDY SELECTION AND DATA EXTRACTION:

English-language, full reports of randomized controlled trials (RCTs) and observational studies evaluating propofol use in adults undergoing procedural sedation in the ED were included if they reported efficacy or safety outcomes. Two reviewers independently assessed each article for inclusion, data extraction, and study limitations.

DATA SYNTHESIS:

Thirteen RCTs and 20 observational studies meeting our inclusion criteria were retrieved. Regardless of the agent used for sedation, procedural success was greater than 80% and most trials demonstrated no statistically significant difference in the incidence of respiratory depression with propofol compared to alternatives. One RCT showed a significantly greater percent decrease in systolic blood pressure from baseline in those who received propofol compared to ketamine. Where reported, no significant difference was found in patient recall, pain, and satisfaction when opioids were added to propofol compared to propofol alone; the addition of opioids may have resulted in a higher incidence of respiratory adverse events.

CONCLUSIONS:

Propofol for procedural sedation is a reasonable alternative for use in the ED, with comparative efficacy and safety to other alternatives. Use of opioids in addition to propofol may not provide added benefit but does contribute to increased rates of adverse events.

Ketamine: use in anesthesia

The role of ketamine anesthesia in the prehospital, emergency department and operating theater settings is not well defined. A nonsystematic review of ketamine was performed by authors from Australia, Europe, and North America. Results were discussed among authors and the final manuscript accepted. Ketamine is a useful agent for induction of anesthesia, procedural sedation, and analgesia. Its properties are appealing in many awkward clinical scenarios. Practitioners need to be cognizant of its side effects and limitations.

Sedation-assisted Orthopedic Reduction in Emergency Medicine: The Safety and Success of a One Physician/One Nurse Model

Introduction

Much of the emergency medical research on sedation-assisted orthopedic reductions has been undertaken with two physicians––one dedicated to the sedation and one to the procedure. Clinical practice in community emergency departments (EDs), however, often involves only one physician, who both performs the procedure and simultaneously oversees the crendentialed registered nurse who administers the sedation medication and monitors the patient. Although the dual-physician model is advocated by some, evidence in support of its superiority is lacking.

Methods:

In this electronic health records review we describe sedation-assisted closed reductions of major joints and forearm fractures in three suburban community EDs. The type of procedure and sedation medication, need for specialty assistance, success rates, and intervention-requiring adverse events are reported.

Results:

During the 18-month study period, procedural sedation was performed 457 times on 442 patients undergoing closed reduction for shoulder dislocations (n = 111), elbow dislocations (n = 29), hip dislocations (n = 101), and forearm fractures (n = 201). In the vast majority of this cohort (98.4% [435/442]), a single emergency physician simultaneously managed both the procedural sedation and the initial orthopedic reduction without the assistance of a second physician. The reduction was successful or satisfactory in 96.6% (425/435; 95% confidence interval [CI], 95.8–98.8%) of these cases, with a low incidence of intervention-requiring adverse events (2.8% [12/435]; 95% CI, 1.5–4.8%).

Conclusion:

Sedation-assisted closed reduction of major joint dislocations and forearm fractures can be performed effectively and safely in the ED using a one physician/one nurse model. A policy that requires a separate physician (or nurse anesthetist) to administer medications for all sedation-assisted ED procedures appears unwarranted. Further research is needed to determine which specific clinical scenarios might benefit from a dual-physician approach.

Clinical implications of pharmacokinetics and pharmacodynamics of procedural sedation agents in children

PURPOSE OF REVIEW

Procedural sedation has become the standard of care for managing pain and anxiety in children in the emergency department.

RECENT FINDINGS

Numerous articles have been published on pediatric procedural sedation with, however, little in-depth discussion of the pharmacodynamics and pharmacokinetics of the sedation agents utilized.

SUMMARY

We review the pharmacokinetics and pharmacodynamics of the pediatric procedural sedation pharmacopeia from a clinical perspective with emphasis on the practical implications for drug titration and dosing.

Ketamine-propofol combination (ketofol) versus propofol alone for emergency department procedural sedation and analgesia: a randomized double-blind trial

STUDY OBJECTIVE

We determine whether a 1:1 mixture of ketamine and propofol (ketofol) for emergency department (ED) procedural sedation results in a 13% or more absolute reduction in adverse respiratory events compared with propofol alone.

METHODS

Participants were randomized to receive either ketofol or propofol in a double-blind fashion. Inclusion criteria were aged 14 years or older and American Society of Anesthesiology class 1 to 3 status. The primary outcome was the number and proportion of patients experiencing an adverse respiratory event as defined by the Quebec Criteria. Secondary outcomes were sedation consistency, efficacy, and time; induction time; and adverse events.

RESULTS

A total of 284 patients were enrolled, 142 per group. Forty-three (30%) patients experienced an adverse respiratory event in the ketofol group compared with 46 (32%) in the propofol group (difference 2%; 95% confidence interval -9% to 13%; P=.80). Three ketofol patients and 1 propofol patient received bag-valve-mask ventilation. Sixty-five (46%) patients receiving ketofol and 93 (65%) patients receiving propofol required repeated medication dosing or progressed to a Ramsay Sedation Score of 4 or less during their procedure (difference 19%; 95% confidence interval 8% to 31%; P=.001). Six patients receiving ketofol were treated for recovery agitation. Other secondary outcomes were similar between the groups. Patients and staff were highly satisfied with both agents.

CONCLUSION

Ketofol for ED procedural sedation does not result in a reduced incidence of adverse respiratory events compared with propofol alone. Induction time, efficacy, and sedation time were similar; however, sedation depth appeared to be more consistent with ketofol.

Combination of ketamine and propofol versus either agent alone for procedural sedation in the emergency department

PURPOSE

The safety of using ketamine-propofol combinations as an alternative to using either agent alone for procedural sedation is discussed.

SUMMARY

A total of 10 trials comparing the combination of ketamine and propofol with either agent alone for procedural sedation in the emergency department were examined. The evidence reviewed suggests that combining these agents may help to minimize adverse effects such as hypotension and respiratory depression. Ketamine is not commonly used as a single agent in adults because of the risk for emergence reactions; however, when combined with propofol, no significant increase in this adverse effect was found compared with propofol monotherapy. Administering ketamine and propofol can be accomplished by using a two-syringe technique or combining both medications into a single syringe. When two syringes are used, a ketamine 0.3-0.5-mg/kg i.v. bolus dose is administered, followed by a propofol 0.4-1-mg/kg i.v. bolus dose. Sedation is maintained with intermittent i.v. boluses of propofol 0.1-0.5 mg/kg. A 1:1 ratio of ketamine and propofol can also be combined into a single syringe by using the same concentration (10 mg/mL) and equal volumes of each drug, yielding a final concentration of 5 mg/mL for each component.

CONCLUSION

The combined use of ketamine and propofol is a reasonable alternative to propofol alone for procedural sedation in patients at higher risk for respiratory depression or hypotension. Use of the combination requires the development of standardized protocols for drug preparation and dosage to minimize the potential for errors.

Ketamine in Adult Emergency Medicine: Controversies and Recent Advances

Objective:

To review the evidence for the use of ketamine in adult emergency medicine for procedural sedation and analgesia (PSA) and rapid sequence intubation (RSI), as well as to focus on the issues of recovery agitation, combination with propofol for PSA, and the use of ketamine as an induction agent in patients with acute head injury in need of definitive airway management.

Data Sources:

PubMed (1949-July 2011), EMBASE (1980-July 2011), Google Scholar (to July 2011), International Pharmaceutical Abstracts (1964-July 2011), and Cochrane databases were searched independently. A manual search of references was also performed,

Study Selection:

English-language, full reports of experimental and observational studies evaluating ketamine in adults undergoing PSA and RSI in the emergency department (ED) were Included if they reported efficacy or safety outcomes.

Data Extraction:

Two reviewers independently assessed each article for inclusion, data extraction, and study limitations.

Data Synthesis:

Six studies that used ketamine for PSA were included. The majority reported adequate sedation with high patient satisfaction and lack of pain and procedural recall. There is no evidence to support the superiority of a combination of ketamine and propofol compared to propofol alone for PSA in adults. Recovery agitation is common but can be minimized with premedication with midazolam (number needed to treat 6). Two studies were identified that evaluated the role of ketamine for induction during RSI in the ED, Although ketamine is not a first-line agent for RSI, it is an alternative and may be used as an induction agent in patients requiring endotracheal intubation.

Conclusions:

Ketamine is an effective agent in adults undergoing PSA and RSI in the ED. The best available evidence provides sufficient confidence to consider use of this agent in the ED.