Ketamine use for rapid sequence intubation in Australian and New Zealand emergency departments from 2010 to 2015: A registry study

Does the choice of induction agent in rapid sequence intubation in the emergency department influence the incidence of post-induction hypotension?

OBJECTIVE

To describe the effects of different induction agents on the incidence of post-induction hypotension (PIH) and its associated interventions during rapid sequence intubation (RSI) in the ED.

METHODS

A single centre retrospective study of patients intubated between 2018 and 2021 was conducted in a regional Australian ED. The impact of induction agent choice, in addition to demographic and clinical factors on the incidence of PIH were determined using descriptive statistics and a multivariate analysis presented as adjusted odds ratios (aORs) and their 95% confidence intervals (CIs).

RESULTS

Ketamine and propofol, used either individually or in conjunction with fentanyl, were significantly associated with PIH (ketamine aOR 4.5, 95% CI 1.35-14.96; propofol aOR 4.88, 95% CI 1.46-16.29). Age >60 years was associated with a greater requirement for vasopressors (aOR 4.46, 95% CI 2.49-7.97) and a higher risk of mortality after RSI (aOR 4.2, 95% CI 1.87-9.40). Patients with a shock index >1.0 were significantly more likely to require vasopressors (aOR 5.13, 95% CI 2.35-11.2) and have a cardiac arrest within 15 min of RSI (aOR 3.56, 95% CI 1.07-11.8).

CONCLUSIONS

Exposure to both propofol and ketamine is significantly associated with PIH after RSI, alongside age and shock index. PIH is likely multifactorial in nature, and this data supports the sympatholytic effect of induction agents as the underlying cause of PIH rather than the choice of agent itself. Further prospective work including a randomised controlled trial between induction agents is justified to further clarify this important clinical question.

The effect of ketamine and fentanyl on haemodynamics during intubation in pre-hospital and retrieval medicine

BACKGROUND

Ketamine use for rapid sequence intubation (RSI) is frequent in pre-hospital and retrieval medicine (PHARM) and is associated with potentially deleterious haemodynamic changes, which may be ameliorated by concurrent use of fentanyl.

OBJECTIVES

To describe the frequency with which fentanyl is used in conjunction with ketamine in a system where its use is discretionary, and to explore any observed changes in haemodynamics with its use.

METHODS

A retrospective observational study of over 800 patients undergoing RSI with ketamine ± fentanyl in the PHARM setting between 2015 and 2019. The primary outcome was the proportion of patients in each group who had a systolic blood pressure (SBP) outside a pre-specified target range, with adjustment for baseline abnormality, within 10 min of anaesthetic induction.

RESULTS

Eight hundred and seventy-six patients were anaesthetised with ketamine, of whom 804 were included in the analysis. 669 (83%, 95% CI 80%-86%) received ketamine alone, and 135 (17%, 95% CI 14%-20%) received both fentanyl and ketamine. Median fentanyl dose was 1.1 mcg/kg (IQR 0.75-1.5 mcg/kg). Systolic blood pressure (SBP) at induction was consistently associated with SBP after intubation in multivariable logistic regression, but fentanyl use was not associated with a change in odds of meeting the primary outcome (OR 1.08; 95% CI 0.72-1.60), becoming hypertensive (OR 1.35; 95% CI 0.88-2.07) or hypotensive (OR 0.76; 95% CI 0.47-1.21).

CONCLUSIONS

The addition of fentanyl to ketamine for RSI was not associated with an alteration of the odds of post-induction haemodynamic stability, although the doses used were low. These findings justify further study into the optimal dosing of fentanyl during RSI in pre-hospital and retrieval medicine.

Fentanyl versus placebo with ketamine and rocuronium for patients undergoing rapid sequence intubation in the emergency department: The FAKT study-A randomized clinical trial

Objective

The objective was to determine whether the use of fentanyl with ketamine for emergency department (ED) rapid sequence intubation (RSI) results in fewer patients with systolic blood pressure (SBP) measurements outside the pre‐specified target range of 100–150 mm Hg following the induction of anesthesia.

Methods

This study was conducted in the ED of five Australian hospitals. A total of 290 participants were randomized to receive either fentanyl or 0.9% saline (placebo) in combination with ketamine and rocuronium, according to a weight‐based dosing schedule. The primary outcome was the proportion of patients in each group with at least one SBP measurement outside the prespecified range of 100–150 mm Hg (with adjustment for baseline abnormality). Secondary outcomes included first‐pass intubation success, hypotension, hypertension and hypoxia, mortality, and ventilator‐free days 30 days following enrollment.

Results

A total of 142 in the fentanyl group and 148 in the placebo group commenced the protocol. A total of 66% of patients receiving fentanyl and 65% of patients receiving placebo met the primary outcome (difference = 1%, 95% CI = −10 to 12). Hypotension (SBP ≤ 99 mm Hg) was more common with fentanyl (29% vs. 16%; difference = 13%, 95% CI = 3% to 23%), while hypertension (≥150 mm Hg) occurred more with placebo (69% vs. 55%; difference = 14%, 95% CI = 3 to 24). First‐pass success rate, 30 day mortality, and ventilator‐free days were similar.

Conclusions and Relevance

There was no difference in the primary outcome between groups, although lower blood pressures were more common with fentanyl. Clinicians should consider baseline hemodynamics and postinduction targets when deciding whether to use fentanyl as a coinduction agent with ketamine.

Mapping haemodynamic changes with rapid sequence induction agents in the emergency department

OBJECTIVE

Patients intubated in the ED are at an increased risk of post-intubation hypotension. However, evidence regarding the most appropriate induction agent is lacking. The present study aims to describe and compare the haemodynamic effect of propofol, ketamine and thiopentone during rapid sequence induction.

METHODS

This is an observational study using data prospectively collected from the Australian and New Zealand Emergency Department Airway Registry between June 2012 and March 2019. The distribution of induction agents across medical and trauma patients were obtained with descriptive statistics. The relationship between induction agent, dose and change in pre- and post-intubation systolic blood pressure (SBP) was described using multivariable logistic regression. The SBP pre- and post-intubation was the primary measure of haemodynamic stability.

RESULTS

From the 5063 intubation episodes, 2229 met the inclusion criteria. Of those, 785 (35.2%) patients were induced with thiopentone, 773 (34.7%) with propofol and 671 (30.1%) with ketamine. Of the included population, 396 (17.8%) patients experienced a reduction in pre-intubation SBP exceeding 20%. Both propofol (P = 0.01) and ketamine (P = 0.01) had an independent and dose-dependent association with hypotension, noting that a higher proportion of patients induced with ketamine had a shock index exceeding 0.9.

CONCLUSION

Propofol was associated with post-intubation hypotension and it is recommended clinicians consider using the lowest effective dose to reduce this risk. Reflecting its perceived haemodynamic stability, patients who received ketamine were more likely to have a higher shock index; however, there was also an association with post-intubation hypotension.

Current airway management practices after a failed intubation attempt in Australian and New Zealand emergency departments

OBJECTIVE

The aims of the present study were to describe current airway management practices after a failed intubation attempt in Australian and New Zealand EDs and to explore factors associated with second attempt success.

METHODS

Data were collected from a multicentre airway registry (The Australian and New Zealand Emergency Department Airway Registry). All intubation episodes that required a second attempt between March 2010 and November 2015 were analysed. Analysis for association with success at the second attempt was undertaken for patient factors including predicted difficulty of laryngoscopy, as well as for changes in laryngoscope type, adjunct devices, intubator and intubating manoeuvres.

RESULTS

Of the 762 patients with a failed first intubation attempt, 603 (79.1%) were intubated successfully at the second attempt. The majority of second attempts were undertaken by emergency consultants (36.8%) and emergency registrars (34.2%). A change in intubator occurred in 56.5% of intubation episodes and was associated with higher second attempt success (unadjusted odds ratio [OR] 1.85; 95% confidence interval [CI] 1.29-2.65). In 69.7% of second attempts at intubation, there was no change in laryngoscope type. Changes in laryngoscope type, adjunct devices and intubation manoeuvres were not significantly associated with success at the second attempt. In adjusted analyses, second attempt success was higher for a change from a non-consultant intubator to a consultant intubator from any specialty (adjusted OR 2.31; 95% CI 1.35-3.95) and where laryngoscopy was not predicted to be difficult (adjusted OR 2.58; 95% CI 1.58-4.21).

CONCLUSIONS

The majority of second intubation attempts were undertaken by emergency consultants and registrars. A change from a non-consultant intubator to a consultant intubator of any specialty for the second attempt and intubation episodes where laryngoscopy was predicted to be non-difficult were associated with a higher success rate at intubation. Participation in routine collection and monitoring of airway management practices via a Registry may enable the introduction of appropriate improvements in airway procedures and reduce complication rates.

Ketamine for rapid sequence intubation in adult trauma patients: A retrospective observational study

BACKGROUND

In the trauma population, ketamine is commonly used during rapid sequence induction. However, as ketamine has been associated with important side effects, this study sought to compare in-hospital mortality in trauma patients after induction with ketamine versus other induction agents.

METHODS

We retrospectively identified adult trauma patients intubated in the pre-hospital phase or initially in the trauma bay at two urban level-1 trauma centers during a 2-year period using local trauma registries and medical records. In-hospital mortality was compared for patients intubated with ketamine versus other agents using logistic regression with adjustment for age, gender, Injury Severity Score (ISS), systolic blood pressure (SBP) < 90 mm Hg, and pre-hospital Glasgow Coma Scale (GCS) score.

RESULTS

A total of 343 trauma patients were included with a median ISS of 25 [17-34]. The most frequently used induction agents were ketamine (36%) and propofol (36%) followed by etomidate (9%) and midazolam (5%). There was no difference in ISS or the presence of SBP <90 mm Hg according to the agent of choice, but the pre-hospital GCS score was higher for patients intubated with ketamine (median 8 vs 5, P = .001). The mortality for patients intubated with ketamine was 18% vs 27% for patients intubated with other agents (P = .14). This remained statistically insignificant in the multivariable logistic regression analysis (odds ratio 0.68 [0.33-1.41], P = .30).

CONCLUSIONS

We found no statistically significant difference in mortality among patients intubated in the initial phase post-trauma with the use of ketamine compared with other agents (propofol, etomidate, or midazolam).

FentAnyl or placebo with KeTamine for emergency department rapid sequence intubation: The FAKT study protocol

BACKGROUND

Some critically ill patients require rapid sequence intubation in the emergency department, and ketamine is one sedative agent employed, due to its relative haemodynamic stability. Tachycardia and hypertension are frequent side effects, and in less stable patients, shock can be unmasked or exacerbated. The use of fentanyl as a co-induction agent may lead to a smoother haemodynamic profile post-induction, which may lead to reduced mortality in this critically ill cohort. This randomised controlled trial aims to compare the effect of administering fentanyl vs placebo in a standardised induction regimen with ketamine and rocuronium on (a) the percentage of patients in each group with a systolic blood pressure outside the range of 100-150 mm Hg within 10 minutes of induction, (b) the laryngoscopic view, and (c) 30-day mortality.

METHODS/DESIGN

Three hundred patients requiring rapid sequence intubation in participating emergency departments will be randomised to receive either fentanyl or placebo (0.9% saline) in addition to ketamine and rocuronium according to a standardised, weight-based induction regimen. The primary outcome measure is the percentage of patients in each group with a systolic blood pressure outside the range of 100-150 mm Hg within 10 minutes of induction. Secondary outcome measures include the laryngoscopic view, percentage of first pass success, 30-day mortality and number of ventilator-free days at 30 days.

DISCUSSION

The effect of adding fentanyl to an induction regimen of ketamine and rocuronium will be evaluated, both in terms of post-intubation physiology, the effect on intubating conditions, and 30-day mortality.