Impact of Ketamine on Analgosedative Consumption in Critically Ill Patients: A Systematic Review and Meta-Analysis

Comparing the hemodynamic effects of ketamine versus fentanyl bolus in patients with septic shock: a randomized controlled trial

BACKGROUND

Ketamine and fentanyl are commonly used for sedation and induction of anesthesia in critically ill patients. This study aimed to compare the hemodynamic effects of ketamine versus fentanyl bolus in patients with septic shock.

METHODS

This randomized controlled trial included mechanically ventilated adults with septic shock receiving sedation. Patients were randomized to receive either 1 mg/kg ketamine bolus or 1 mcg/kg fentanyl bolus. Cardiac output (CO), stroke volume (SV), heart rate (HR), and mean arterial pressure (MAP) were measured at the baseline, 3, 6, 10, and 15 min after the intervention. Delta CO was calculated as the change in CO at each time point in relation to baseline measurement. The primary outcome was delta CO 6 min after administration of the study drug. Other outcomes included CO, SV, HR, and MAP.

RESULTS

Eighty-six patients were analyzed. The median (quartiles) delta CO 6 min after drug injection was 71(37, 116)% in the ketamine group versus - 31(- 43, - 12)% in the fentanyl group, P value < 0.001. The CO, SV, HR, and MAP increased in the ketamine group and decreased in the fentanyl group in relation to the baseline reading; and all were higher in the ketamine group than the fentanyl group.

CONCLUSION

In patients with septic shock, ketamine bolus was associated with higher CO and SV compared to fentanyl bolus.

CLINICAL TRIAL REGISTRATION

Date of registration: 24/07/2023.

CLINICALTRIALS

gov Identifier: NCT05957302. URL: https://clinicaltrials.gov/study/NCT05957302 .

Sedation in the ICU

AbstractSedation practices are key to improving intensive care unit (ICU) outcomes. Adequate treatment of pain, minimization of sedation, delirium prevention, and improved patient interaction to ensure early rehabilitation and faster ventilator liberation are evidenced-based components of ICU care. Here we review components of appropriate ICU sedation including the use of multicomponent care bundles such as the ABCDEF bundle with a focus on changes in ICU practice that followed the Covid-19 pandemic.

Ketamine analgo-sedation for mechanically ventilated critically ill adults: A rapid practice guideline from the Saudi Critical Care Society and the Scandinavian Society of Anesthesiology and Intensive Care Medicine

BACKGROUND

This Rapid Practice Guideline (RPG) aimed to provide evidence-based recommendations for ketamine analgo-sedation (monotherapy and adjunct) versus non-ketamine sedatives or usual care in adult intensive care unit (ICU) patients on invasive mechanical ventilation (iMV) and to identify knowledge gaps for future research.

METHODS

The RPG panel comprised 23 multinational multidisciplinary panelists, including a patient representative. An up-to-date systematic review and meta-analysis constituted the evidence base. The Grading Recommendations, Assessment, Development, and Evaluation approach, and the evidence-to-decision framework were used to assess the certainty of evidence and to move from evidence to decision/recommendation. The panel provided input on the balance of the desirable and undesirable effects, certainty of evidence, patients' values and preferences, costs, resources, equity, feasibility, acceptability, and research priorities.

RESULTS

Data from 17 randomized clinical trials (n = 898) and nine observational studies (n = 1934) were included. There was considerable uncertainty about the desirable and undesirable effects of ketamine monotherapy for analgo-sedation. The evidence was very low certainty and downgraded for risk of bias, indirectness, and inconsistency. Uncertainty or variability in values and preferences were identified. Costs, resources, equity, and acceptability were considered varied. Adjunctive ketamine therapy had no effect on mortality (within 28 days) (relative risk [RR] 0.99; 95% confidence interval [CI] 0.76 to 1.27; low certainty), and may slightly reduce iMV duration (days) (mean difference [MD] -0.05 days; 95% CI -0.07 to -0.03; low certainty), and uncertain effect on the cumulative dose of opioids (mcg/kg/h morphine equivalent) (MD -11.6; 95% CI -20.4 to -2.7; very low certainty). Uncertain desirable effects (cumulative dose of sedatives and vasopressors) and undesirable effects (adverse event rate, delirium, arrhythmia, hepatotoxicity, hypersalivation, use of physical restraints) were also identified. A possibility of important uncertainty or variability in patient-important outcomes led to a balanced effect that favored neither the intervention nor the comparison. Cost, resources, and equity were considered varied.

CONCLUSION

The RPG panel provided two conditional recommendations and suggested (1) against using ketamine as monotherapy analgo-sedation in critically ill adults on iMV when other analgo-sedatives are available; and (2) using ketamine as an adjunct to non-ketamine usual care sedatives (e.g., opioids, propofol, dexmedetomidine) or continuing with non-ketamine usual care sedatives alone. Large-scale trials should provide additional evidence.

Impact of Prolonged Continuous Ketamine Infusions in Critically Ill Children: A Prospective Cohort Study

BACKGROUND

Ketamine has been considered as an adjunct for children who do not reach their predefined target sedation depth. However, there is limited evidence regarding the use of ketamine as a prolonged infusion (i.e., >24 hours) in the pediatric intensive care unit (PICU).

OBJECTIVE

We sought to evaluate the safety and effectiveness of continuous ketamine infusion for >24 hours in mechanically ventilated children.

METHODS

We conducted a prospective cohort study in a tertiary PICU from January 2020 to December 2022. The primary outcome was the incidence of adverse events (AEs) after ketamine initiation. The secondary outcome included assessing the median proportion of time the patient spent on the Richmond Agitation-Sedation Scale (RASS) goal after ketamine infusion. Patients were also divided into two groups based on the sedative regimen, ketamine-based or non-ketamine-based, to assess the incidence of delirium.

RESULTS

A total of 269 patients were enrolled: 73 in the ketamine group and 196 in the non-ketamine group. The median infusion rate of ketamine was 1.4 mg/kg/h. Delirium occurred in 16 (22%) patients with ketamine and 15 (7.6%) patients without ketamine (p = 0.006). After adjusting for covariates, logistic regression showed that delirium was associated with comorbidities (odds ratio [OR] 4.2), neurodevelopmental delay (OR 0.23), fentanyl use (OR 7.35), and ketamine use (OR 4.17). Thirty-one (42%) of the patients experienced at least one AE following ketamine infusion. Other AEs likely related to ketamine were hypertension (n = 4), hypersecretion (n = 14), tachycardia (n = 6), and nystagmus (n = 2). There were no significant changes in hemodynamic variables 24 h after the initiation of ketamine. Regarding the secondary outcomes, patients were at their goal RASS level for a median of 76% (range 68-80.5%) of the time in the 24 hours before ketamine initiation, compared with 84% (range 74.5-90%) of the time during the 24 h after ketamine initiation (p < 0.001). The infusion rate of ketamine did not significantly affect concomitant analgesic and sedative infusions. The ketamine group experienced a longer duration of mechanical ventilation and a longer length of stay in the PICU and hospital than the non-ketamine group.

CONCLUSION

The use of ketamine infusion in PICU patients may be associated with an increased rate of adverse events, especially delirium. High-quality studies are needed before ketamine can be broadly recommended or adopted earlier in the sedation protocol.

Ketamine Analgo-sedation for Mechanically Ventilated Critically Ill Adults: A Rapid Practice Guideline from the Saudi Critical Care Society and the Scandinavian Society of Anesthesiology and Intensive Care Medicine

BACKGROUND

This Rapid Practice Guideline (RPG) aimed to provide evidence‑based recommendations for ketamine analgo-sedation (monotherapy and adjunct) versus non-ketamine sedatives or usual care in adult intensive care unit (ICU) patients on invasive mechanical ventilation (iMV) and to identify knowledge gaps for future research.

METHODS

The RPG panel comprised 23 multinational multidisciplinary panelists, including a patient representative. An up-to-date systematic review and meta-analysis constituted the evidence base. The Grading Recommendations, Assessment, Development, and Evaluation approach, and the evidence-to-decision framework were used to assess the certainty of evidence and to move from evidence to decision/recommendation. The panel provided input on the balance of the desirable and undesirable effects, certainty of evidence, patients' values and preferences, costs, resources, equity, feasibility, acceptability, and research priorities.

RESULTS

Data from 17 randomized clinical trials (n=898) and 9 observational studies (n=1934) were included. There was considerable uncertainty about the desirable and undesirable effects of ketamine monotherapy for analgo-sedation. The evidence was very low certainty and downgraded for risk of bias, indirectness, and inconsistency. Uncertainty or variability in values and preferences were identified. Costs, resources, equity, and acceptability were considered varied. Adjunctive ketamine therapy had no effect on mortality (within 28 days) (relative risk [RR] 0.99; 95% confidence interval [CI] 0.76 to 1.27; low certainty), and may slightly reduce iMV duration (days) (mean difference [MD] -0.05 days; 95% CI -0.07 to -0.03; low certainty), and uncertain effect on the cumulative dose of opioids (mcg/kg/h morphine equivalent) (MD -11.6; 95% CI -20.4 to -2.7; very low certainty). Uncertain desirable effects (cumulative dose of sedatives and vasopressors) and undesirable effects (adverse event rate, delirium, arrhythmia, hepatotoxicity, hypersalivation, use of physical restraints) were also identified. A possibility of important uncertainty or variability in patient-important outcomes led to a balanced effect that favored neither the intervention nor the comparison. Cost, resources, and equity were considered varied.

CONCLUSION

The RPG panel provided two conditional recommendations and suggested (1) against using ketamine as monotherapy analgo-sedation in critically ill adults on iMV when other analgo-sedatives are available; and (2) using ketamine as an adjunct to non-ketamine usual care sedatives (e.g., opioids, propofol, dexmedetomidine) or continuing with non-ketamine usual care sedatives alone. Large-scale trials should provide additional evidence.

Use of Early Ketamine Sedation and Association With Clinical and Cost Outcomes Among Mechanically Ventilated Patients With COVID-19: A Retrospective Cohort Study

OBJECTIVES

To describe the utilization of early ketamine use among patients mechanically ventilated for COVID-19, and examine associations with in-hospital mortality and other clinical outcomes.

DESIGN

Retrospective cohort study.

SETTING

Six hundred ten hospitals contributing data to the Premier Healthcare Database between April 2020 and June 2021.

PATIENTS

Adults with COVID-19 and greater than or equal to 2 consecutive days of mechanical ventilation within 5 days of hospitalization.

INTERVENTION

The exposures were early ketamine use initiated within 2 days of intubation and continued for greater than 1 day.

MEASUREMENTS

Primary was hospital mortality. Secondary outcomes included length of stay (LOS) in the hospital and ICUs, ventilator days, vasopressor days, renal replacement therapy (RRT), and total hospital cost. The propensity score matching analysis was used to adjust for confounders.

MAIN RESULTS

Among 42,954 patients, 1,423 (3.3%) were exposed to early ketamine use. After propensity score matching including 1,390 patients in each group, recipients of ketamine infusions were associated with higher hospital mortality (52.5% vs. 45.9%, risk ratio: 1.14, [1.06-1.23]), longer median ICU stay (13 vs. 12 d, mean ratio [MR]: 1.15 [1.08-1.23]), and longer ventilator days (12 vs. 11 d, MR: 1.19 [1.12-1.27]). There were no associations for hospital LOS (17 [10-27] vs. 17 [9-28], MR: 1.05 [0.99-1.12]), vasopressor days (4 vs. 4, MR: 1.04 [0.95-1.14]), and RRT (22.9% vs. 21.7%, RR: 1.05 [0.92-1.21]). Total hospital cost was higher (median $72,481 vs. $65,584, MR: 1.11 [1.05-1.19]).

CONCLUSIONS

In a diverse sample of U.S. hospitals, about one in 30 patients mechanically ventilated with COVID-19 received ketamine infusions. Early ketamine may have an association with higher hospital mortality, increased total cost, ICU stay, and ventilator days, but no associations for hospital LOS, vasopressor days, and RRT. However, confounding by the severity of illness might occur due to higher extracorporeal membrane oxygenation and RRT use in the ketamine group. Further randomized trials are needed to better understand the role of ketamine infusions in the management of critically ill patients.

Experiential Learning with Ketamine: A Mixed-Methods Exploratory Study on Prescription and Perception

Background

Incorporating unfamiliar therapies into practice requires effective longitudinal learning and the optimal way to achieve this is debated. Though not a novel therapy, ketamine in critical care has a paucity of data and variable acceptance, with limited research describing intensivist perceptions and utilization. The Coronavirus-19 pandemic presented a particular crisis where providers rapidly adapted analgosedation strategies to achieve prolonged, deep sedation due to a surge of severe acute respiratory distress syndrome (ARDS).

Question

How does clinical experience with ketamine impact the perception and attitude of clinicians toward this therapy?

Methods

We conducted a mixed-methods study using quantitative ketamine prescription data and qualitative focus group data. We analyzed prescription patterns of ketamine in a tertiary academic ICU during two different time points: pre-COVID-19 (March 1-June 30, 2019) and during the COVID-19 surge (March 1-June 30, 2020). Two focus groups (FG) of critical care attendings were held, and data were analyzed using the Framework Method for content analysis.

Results

Four-hundred forty-six medical ICU patients were mechanically ventilated (195 pre-COVID-19 and 251 during COVID-19). The COVID-19 population was more likely to receive ketamine (81[32.3%] vs 4 [2.1%], p < 0.001). Thirteen respondents participated across two FG sessions (Pre-COVID = 8, Post-COVID=5). The most prevalent attitude among our respondents was discomfort, with three key themes identified as follows: 1) lack of evidence regarding ketamine, 2) lack of personal experience, and 3) desire for more education and protocols.

Conclusion

Despite a substantial increase in ketamine prescription during COVID-19, intensivists continued to feel discomfort with utilization. Factors contributing to this discomfort include a lack of evidence, a lack of experience, and a desire for more education and protocols. Increase in experience with ketamine alone was not sufficient to minimize provider discomfort. These findings should inform future curricula and call for process improvement to optimize continuing education.

Ketamine-based Sedation Use in Mechanically Ventilated Critically Ill Patients with COVID-19: A Multicenter Cohort Study

Backgrounds

Ketamine possesses analgesia, anti-inflammation, anticonvulsant, and neuroprotection properties. However, the evidence that supports its use in mechanically ventilated critically ill patients with COVID-19 is insufficient. The study's goal was to assess ketamine's effectiveness and safety in critically ill, mechanically ventilated (MV) patients with COVID-19.

Methods

Adult critically ill patients with COVID-19 were included in a multicenter retrospective-prospective cohort study. Patients admitted between March 1, 2020, and July 31, 2021, to five ICUs in Saudi Arabia were included. Eligible patients who required MV within 24 hours of ICU admission were divided into two sub-cohort groups based on their use of ketamine (Control vs. Ketamine). The primary outcome was the length of stay (LOS) in the hospital. P/F ratio differences, lactic acid normalization, MV duration, and mortality were considered secondary outcomes. Propensity score (PS) matching was used (1:2 ratio) based on the selected criteria.

Results

In total, 1,130 patients met the eligibility criteria. Among these, 1036 patients (91.7 %) were in the control group, whereas 94 patients (8.3 %) received ketamine. The total number of patients after PS matching, was 264 patients, including 88 patients (33.3 %) who received ketamine. The ketamine group's LOS was significantly lower (beta coefficient (95 % CI): -0.26 (-0.45, -0.07), P = 0.008). Furthermore, the PaO2/FiO2 ratio significantly improved 24 hours after the start of ketamine treatment compared to the pre-treatment period (6 hours) (124.9 (92.1, 184.5) vs. 106 (73.1, 129.3; P = 0.002). Additionally, the ketamine group had a substantially shorter mean time for lactic acid normalization (beta coefficient (95 % CI): -1.55 (-2.42, -0.69), P 0.01). However, there were no significant differences in the duration of MV or mortality.

Conclusions

Ketamine-based sedation was associated with lower hospital LOS and faster lactic acid normalization but no mortality benefits in critically ill patients with COVID-19. Thus, larger prospective studies are recommended to assess the safety and effectiveness of ketamine as a sedative in critically ill adult patients.

Pain Management Strategies in Intensive Care Unit: Challenges and Best Practice

Pain management in the ICU (intensive care unit) is a very complex problem which involves a wide variety of conditions, lack of sufficient tools for use, and high personnel to patient ratio. In the last three decades, pain as a clinical issue has become well analyzed, and treatment protocols based on scientific evidence have been established. Besides medication, some non-pharmacological methods such as music therapy, relaxation, and massage have been proven to be very much practical and manageable in pain management of ICU. The main opioids are utilized predominantly due to their power but NSAIDs and local anesthesia are combined with opioids with the aim to reduce the pain as much as possible. Yet more research now has to prove that pain evaluation and management is effective. This article discusses on the issues and the best approaches to solving them when managing pain in ICU patients.

The impact of ketamine on outcomes in critically ill patients: a systematic review with meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND

This meta-analysis aims to evaluate the effects of ketamine in critically ill intensive care unit (ICU) patients.

METHODS

We searched for randomized controlled trials (RCTs) in PubMed, Scopus, and the Cochrane Library; the search was performed initially in January but was repeated in December of 2023. We focused on ICU patients of any age. We included studies that compared ketamine with other traditional agents used in the ICU. We synthesized evidence using RevMan v5.4 and presented the results as forest plots. We also used trial sequential analysis (TSA) software v. 0.9.5.10 Beta and presented results as TSA plots. For synthesizing results, we used a random-effects model and reported differences in outcomes of two groups in terms of mean difference (MD), standardized MD, and risk ratio with 95% confidence interval. We assessed the risk of bias using the Cochrane RoB tool for RCTs. Our outcomes were mortality, pain, opioid and midazolam requirements, delirium rates, and ICU length of stay.

RESULTS

Twelve RCTs involving 805 ICU patients (ketamine group, n=398; control group, n=407) were included in the meta-analysis. The ketamine group was not superior to the control group in terms of mortality (in five studies with 318 patients), pain (two studies with 129 patients), mean and cumulative opioid consumption (six studies with 494 patients), midazolam consumption (six studies with 304 patients), and ICU length of stay (three studies with 270 patients). However, the model favored the ketamine group over the control group in delirium rate (four studies with 358 patients). This result is significant in terms of conventional boundaries (alpha=5%) but is not robust in sequential analysis. The applicability of the findings is limited by the small number of patients pooled for each outcome.

CONCLUSIONS

Our meta-analysis did not demonstrate differences between ketamine and control groups regarding any outcome except delirium rate, where the model favored the ketamine group over the control group. However, this result is not robust as sensitivity analysis and trial sequential analysis suggest that more RCTs should be conducted in the future.

Ketamine as adjunctive or monotherapy for post-intubation sedation in patients with trauma on mechanical ventilation: A rapid review

Background

The effectiveness of ketamine as adjunctive or monotherapy for post-intubation sedation in adults with trauma on mechanical ventilation is unclear.

Methods

A rapid review of systematic reviews of randomized controlled trials, then randomized controlled trials or observational studies was conducted searching three electronic databases (PubMed, Embase, Cochrane Library) and one clinical trial registry on June 1, 2022. We used a prespecified protocol following Cochrane rapid review methods.

Results

We identified eight systematic reviews of randomized controlled trials and observational studies. Among the included reviews, only the most relevant, up to date, highest quality-assessed reviews and reviews that reported on critical outcomes were considered. Adjunctive ketamine showed a morphine sparing effect (MD -13.19 µmg kg-1 h-1, 95 % CI -22.10 to -4.28, moderate certainty of evidence, 6 RCTs), but no to little effect on midazolam sparing effect (MD 0.75 µmg kg-1 h-1, 95 % CI -1.11 to 2.61, low certainty of evidence, 6 RCTs) or duration of mechanical ventilation in days (MD -0.17 days, 95 % CI -3.03 to 2.69, moderate certainty of evidence, 3 RCTs).Adjunctive ketamine therapy may reduce mortality (OR 0.88, 95 % CI 0.54 to 1.43, P = 0.60, very low certainty of evidence, 5 RCTs, n = 3076 patients) resulting in 30 fewer deaths per 1000, ranging from 132 fewer to 87 more, but the evidence is very uncertain. Ketamine results in little to no difference in length of ICU stay (MD 0.04 days, 95 % CI -0.12 to 0.20, high certainty of evidence, 5 RCTs n = 390 patients) or length of hospital stay (MD -0.53 days, 95 % CI -1.36 to 0.30, high certainty of evidence, 5 RCTs, n = 277 patients).Monotherapy may have a positive effect on respiratory and haemodynamic outcomes, however the evidence is very uncertain.

Conclusion

Adjunctive ketamine for post-intubation analgosedation results in a moderate meaningful net benefit but there is uncertainty for benefit and harms as monotherapy.

Early Sedation Depth and Clinical Outcomes in Mechanically Ventilated Patients in a Hospital: Retrospective Cohort Study

PURPOSE

This study aimed to identify the early sedation depth in the first 48 hours of mechanical ventilation and its relationship to clinical outcomes to promote the transition to light sedation.

METHODS

This retrospective single-center cohort study was conducted in two medical intensive care units (MICUs) at a general tertiary hospital, using a standardized sedation protocol. To investigate the early sedation depth, the Sedation Index was used, which can indicate changes over the first 48 hours. Patients were divided into three groups based on tertiles of Sedation Index. The primary outcome was mortality at 30, 90, and 180 days. The secondary outcomes included length of stay in the ICU and ventilator-free days. Kaplan-Meier analysis and multivariable Cox regression were conducted to compare factors influencing mortality.

RESULTS

This study included 394 patients. The deepest sedation group showed more severe illness, delirium, and deeper sedation at admission (p < .001). The survival curve decreased as sedation increased, even within the light sedation levels. In the deepest sedation group, 30-day mortality (hazard ratio [HR] 2.11, 95% confidence interval [CI] 1.33-3.34), 90-day mortality (HR 2.00, 95% CI 1.31-3.06), and 180-day mortality (HR 1.77, 95% CI 1.17-2.67) increased. The length of stay in the ICU and ventilator-free days did not show statistical differences.

CONCLUSIONS

These results indicate that early deep sedation is a modifiable factor that can potentially affect mortality. The protocol for inducing the transition into light sedation must comply with recommendations to improve clinical outcomes.

Prospective multicenter study of heart rate variability with ANI monitor as predictor of mortality in critically ill patients with COVID-19

The purpose of this study is to demonstrate that the most critically ill patients with COVID-19 have greater autonomic nervous system dysregulation and assessing the heart rate variability, allows us to predict severity and 30-day mortality. This was a multicentre, prospective, cohort study. Patients were divided into two groups depending on the 30-day mortality. The heart rate variability and more specifically the relative parasympathetic activity (ANIm), and the SDNN (Energy), were measured. To predict severity and mortality multivariate analyses of ANIm, Energy, SOFA score, and RASS scales were conducted. 112 patients were collected, the survival group (n = 55) and the deceased group (n = 57). The ANIm value was higher (p = 0.013) and the Energy was lower in the deceased group (p = 0.001); Higher Energy was correlated with higher survival days (p = 0.009), and a limit value of 0.31 s predicted mortalities with a sensitivity of 71.9% and a specificity of 74.5%. Autonomic nervous system and heart rate variability monitoring in critically ill patients with COVID-19 allows for predicting survival days and 30-day mortality through the Energy value. Those patients with greater severity and mortality showed higher sympathetic depletion with a predominance of relative parasympathetic activity.