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

Rapid Sequence Intubation, is it Time to Find an Alternative Induction Agent? A Narrative Review

Objective: To review the efficacy, safety, and place in therapy of fentanyl as an induction agent for rapid sequence intubation (RSI) in critically ill patients. Data Sources: A comprehensive search of PubMed, EMBASE, and clinical trial registries (1964-June 2021) was performed utilizing the keywords fentanyl, rapid sequence intubation, intubation, induction, anesthesia, hemodynamics, operating room (OR), and emergency. Study Selection and Data Extraction: Only primary literature evaluating fentanyl in combination with a sedative or as the sole induction agent was included in the final analysis. Primary literature included peer-reviewed publications and results posted on ClinicalTrials.gov actively recruiting participants. Data Synthesis: Fentanyl has been used for decades as an adjunct, and sole induction agent in the OR. Questions surrounding the use of fentanyl as a sole induction agent include optimal dosing and safety in critically ill patients as evaluation in non-OR settings remain limited. Relevance to Patient Care and Clinical Practice: Commonly used induction agents (eg, etomidate and ketamine) are associated with adverse events that may increase risk of morbidity and mortality. Fentanyl, a high-potency opioid could serve as an alternative induction agent for RSI due to its neutral hemodynamic response and fast onset of action. This paper compiles and describes existing data on the use of fentanyl as an induction agent for RSI. Conclusion: Fentanyl in combination with sedatives provides optimal intubating conditions with minimal impact on hemodynamic parameters. Future studies should focus on safety and impact of awareness during paralysis before fentanyl can be considered as a sole induction agent.

Alfentanil versus fentanyl for emergency department rapid sequence induction with ketamine: A-FAKT, a pilot randomized trial

BACKGROUND

Fentanyl is often administered during rapid sequence induction of anesthesia (RSI) in the emergency department (ED) to ameliorate the hypertensive response that may occur. Due to its more rapid onset, the use of alfentanil may be more consistent with both the onset time of the sedative and the commencement of laryngoscopy. As such, we compared the effect of alfentanil and fentanyl on post-induction hemodynamic changes when administered as part of a standardized induction regimen including ketamine and rocuronium in ED RSI.

METHODS

This was a double-blind pilot randomized controlled trial of adult patients requiring RSI in the ED of three urban Australian hospitals. Patients were randomized to receive either alfentanil or fentanyl in addition to ketamine and rocuronium for RSI. Non-invasive blood pressure and heart rate were measured immediately before and at two, four, and six minutes after induction. The primary outcome was the occurrence of at least one post-induction systolic blood pressure outside the pre-specified range of 100-160mmHg (with adjustment for patients with baseline hypertension). Secondary outcomes included hypertension, hypotension, hypoxia, first-pass intubation success, 30-day mortality, and the pattern of hemodynamic changes.

RESULTS

A total of 61 patients were included in the final analysis (31 in the alfentanil group and 30 in the fentanyl group). The primary outcome was met in 58% of the alfentanil group and 50% of the fentanyl group (difference 8%, 95% confidence interval: -17% to 33%). The 30-day mortality rate, first-pass success rate, and incidences of hypertension, hypotension, and hypoxia were similar between the groups. There were no significant differences in systolic blood pressure or heart rate between the groups at any of the measured time-points.

CONCLUSION

Alfentanil and fentanyl produced comparable post-induction hemodynamic changes when used as adjuncts to ketamine in ED RSI. Future studies could consider comparing different dosages of these opioids.

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.

[Prehospital postcardiac-arrest-sedation and -care in the Federal Republic of Germany-a web-based survey of emergency physicians]

BACKGROUND

This study evaluates the implementation of postcardiac-arrest-sedation (PCAS) and -care (PRC) by prehospital emergency physicians in Germany.

MATERIALS AND METHODS

Analysis of a web-based survey from October to November 2022. Questions were asked about implementation, medications used, complications, motivation for implementing or not implementing PCAS, and measures and target parameters of PRC.

RESULTS

A total of 500 emergency physicians participated in the survey. In all, 73.4% stated that they regularly performed PCAS (hypnotics: 84.7%; analgesics: 71.1%; relaxants: 29.7%). Indications were pressing against the respirator (88.3%), analgesia (74.1%), synchronization to respirator (59.5%), and change of airway device (52.6%). Reasons for not performing PCAS (26.6%) included unconscious patients (73.7%); concern about hypotension (31.6%), re-arrest (26.3%), and worsening neurological assessment (22.5%). Complications of PCAS were observed by 19.3% of participants (acute hypotension [74.6%]); (re-arrest [32.4%]). In addition to baseline monitoring, PRC included 12-lead-electrocardiogram (96.6%); capnography (91.6%); catecholamine therapy (77.6%); focused echocardiography (20.6%), lung ultrasound (12.0%) and abdominal ultrasound (5.6%); induction of hypothermia (13.6%) and blood gas analysis (7.4%). An etCO2 of 35-45 mm Hg was targeted by 40.6%, while 9.0% of participants targeted an SpO2 of 94-98% and 19.2% of participants targeted a systolic blood pressure of ≥ 100 mm Hg.

CONCLUSIONS

Prehospital PRC in Germany is heterogeneous and deviations from its target parameters are frequent. PCAS is frequent and associated with relevant complications. The development of preclinical care algorithms for PCAS and PRC within preclinical care seems urgently needed.

Prehospital anesthesia in postcardiac arrest patients: a multicenter retrospective cohort study

BACKGROUND

Currently, the data regarding the impact of prehospital postcardiac arrest anesthesia on target hemodynamic and ventilatory parameters of early postresuscitation care and recommendations on its implementation are rare. The present study examines the incidence and impact of prehospital postcardiac arrest anesthesia on hemodynamic and ventilatory target parameters of postresuscitation care.

METHODS

In this multicentre observational study between 2019 and 2021 unconscious adult patients after out-of-hospital-cardiac arrest with the presence of a return-of-spontaneous circulation until hospital admission were included. Primary endpoint was the application of postarrest anesthesia. Secondary endpoints included the medication group used, predisposing factors to its implementation, and its influence on achieving target parameters of postresuscitation care (systolic blood pressure: ≥ 100 mmHg, etCO2:35-45 mmHg, SpO2: 94-98%) at hospital handover.

RESULTS

During the study period 2,335 out-of-hospital resuscitations out of 391,305 prehospital emergency operations (incidence: 0.58%; 95% CI 0.54-0.63) were observed with a return of spontaneous circulation to hospital admission in 706 patients (30.7%; 95% CI 28.8-32.6; female: 34.3%; age:68.3 ± 14.2 years). Postcardiac arrest anesthesia was performed in 482 patients (68.3%; 95% CI 64.7-71.7) with application of hypnotics in 93.4% (n = 451), analgesics in 53.7% (n = 259) and relaxants in 45.6% (n = 220). Factors influencing postcardiac arrest sedation were emergency care by an anesthetist (odds ratio: 2.10; 95% CI 1.34-3.30; P < 0.001) and treatment-free interval ≤ 5 min (odds ratio: 1.59; 95% CI 1.01-2.49; P = 0.04). Although there was no evidence of the impact of performing postcardiac arrest anesthesia on achieving a systolic blood pressure ≥ 100 mmHg at the end of operation (odds ratio: 1.14; 95% CI 0.78-1.68; P = 0.48), patients with postcardiac arrest anesthesia were significantly more likely to achieve the recommended ventilation (odds ratio: 1.59; 95% CI 1.06-2.40; P = 0.02) and oxygenation (odds ratio:1.56; 95% CI 1.04-2.35; P = 0.03) targets. Comparing the substance groups, the use of hypnotics significantly more often enabled the target values for etCO2 to be reached alone (odds ratio:2.79; 95% CI 1.04-7.50; P = 0.04) as well as in combination with a systolic blood pressure ≥ 100 mmHg (odds ratio:4.42; 95% CI 1.03-19.01; P = 0.04).

CONCLUSIONS

Postcardiac arrest anesthesia in out-of-hospital cardiac arrest is associated with early achievement of respiratory target parameters in prehospital postresuscitation care without evidence of more frequent hemodynamic complications.

Critical hypertension in trauma patients following prehospital emergency anaesthesia: a multi-centre retrospective observational study

BACKGROUND

Critical hypertension in major trauma patients is associated with increased mortality. Prehospital emergency anaesthesia (PHEA) is performed for 10% of the most seriously injured patients. Optimising oxygenation, ventilation, and cerebral perfusion, whilst avoiding extreme haemodynamic fluctuations are the cornerstones of reducing secondary brain injury. The aim of this study was to report the differential determinants of post-PHEA critical hypertension in a large regional dataset of trauma patients across three Helicopter Emergency Medical Service (HEMS) organisations.

METHODS

A multi-centre retrospective observational study of consecutive adult trauma patients undergoing PHEA across three HEMS in the United Kingdom; 2015-2022. Critical hypertension was defined as a new systolic blood pressure (SBP) > 180mmHg within 10 min of induction of anaesthesia, or > 10% increase if the baseline SBP was > 180mmHg prior to induction. Purposeful logistical regression was used to explore variables associated with post-PHEA critical hypertension in a multivariable model. Data are reported as number (percentage), and odds ratio (OR) with 95% confidence interval (95%CI).

RESULTS

30,744 patients were attended by HEMS during the study period; 2161 received PHEA and 1355 patients were included in the final analysis. 161 (11.9%) patients had one or more new episode(s) of critical hypertension ≤ 10 min post-PHEA. Increasing age (compared with 16-34 years): 35-54 years (OR 1.76, 95%CI 1.03-3.06); 55-74 years (OR 2.00, 95%CI 1.19-3.44); ≥75 years (OR 2.38, 95%CI 1.31-4.35), pre-PHEA Glasgow Coma Scale (GCS) motor score four (OR 2.17, 95%CI 1.19-4.01) and five (OR 2.82, 95%CI 1.60-7.09), patients with a pre-PHEA SBP > 140mmHg (OR 6.72, 95%CI 4.38-10.54), and more than one intubation attempt (OR 1.75, 95%CI 1.01-2.96) were associated with post-PHEA critical hypertension.

CONCLUSION

Delivery of PHEA to seriously injured trauma patients risks haemodynamic fluctuation. In adult trauma patients undergoing PHEA, 11.9% of patients experienced post-PHEA critical hypertension. Increasing age, pre-PHEA GCS motor score four and five, patients with a pre-PHEA SBP > 140mmHg, and more than intubation attempt were independently associated with post-PHEA critical hypertension.

Molecular insights into GPCR mechanisms for drugs of abuse

Substance abuse is on the rise, and while many people may use illicit drugs mainly due to their rewarding effects, their societal impact can range from severe, as is the case for opioids, to promising, as is the case for psychedelics. Common with all these drugs' mechanisms of action are G protein-coupled receptors (GPCRs), which lie at the center of how these drugs mediate inebriation, lethality, and therapeutic effects. Opioids like fentanyl, cannabinoids like tetrahydrocannabinol, and psychedelics like lysergic acid diethylamide all directly bind to GPCRs to initiate signaling which elicits their physiological actions. We herein review recent structural studies and provide insights into the molecular mechanisms of opioids, cannabinoids, and psychedelics at their respective GPCR subtypes. We further discuss how such mechanistic insights facilitate drug discovery, either toward the development of novel therapies to combat drug abuse or toward harnessing therapeutic potential.

Predictors of post-intubation hypotension in trauma patients following prehospital emergency anaesthesia: a multi-centre observational study

BACKGROUND

Post-intubation hypotension (PIH) after prehospital emergency anaesthesia (PHEA) is prevalent and associated with increased mortality in trauma patients. The objective of this study was to compare the differential determinants of PIH in adult trauma patients undergoing PHEA.

METHODS

This multi-centre retrospective observational study was performed across three Helicopter Emergency Medical Services (HEMS) in the UK. Consecutive sampling of trauma patients who underwent PHEA using a fentanyl, ketamine, rocuronium drug regime were included, 2015-2020. Hypotension was defined as a new systolic blood pressure (SBP) < 90 mmHg within 10 min of induction, or > 10% reduction if SBP was < 90 mmHg before induction. A purposeful selection logistic regression model was used to determine pre-PHEA variables associated with PIH.

RESULTS

During the study period 21,848 patients were attended, and 1,583 trauma patients underwent PHEA. The final analysis included 998 patients. 218 (21.8%) patients had one or more episode(s) of hypotension ≤ 10 min of induction. Patients > 55 years old; pre-PHEA tachycardia; multi-system injuries; and intravenous crystalloid administration before arrival of the HEMS team were the variables significantly associated with PIH. Induction drug regimes in which fentanyl was omitted (0:1:1 and 0:0:1 (rocuronium-only)) were the determinants with the largest effect sizes associated with hypotension.

CONCLUSION

The variables significantly associated with PIH only account for a small proportion of the observed outcome. Clinician gestalt and provider intuition is likely to be the strongest predictor of PIH, suggested by the choice of a reduced dose induction and/or the omission of fentanyl during the anaesthetic for patients perceived to be at highest risk.

Intubation practices and outcomes for patients with suspected or confirmed COVID-19: a national observational study by the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN)

OBJECTIVE

Intubation practices changed during the COVID-19 pandemic to protect healthcare workers from transmission of disease. Our objectives were to describe intubation characteristics and outcomes for patients tested for SARS CoV-2 infection. We compared outcomes between patients testing SARS COV-2 positive with those testing negative.

METHODS

We conducted a health records review using the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) registry. We included consecutive eligible patients who presented to one of 47 EDs across Canada between March 1, 2020 and June 20, 2021, were tested for SARS-CoV-2 and intubated in the ED. The primary outcome was the proportion of patients experiencing a post-intubation adverse event during the ED stay. Secondary outcomes included first-pass success, intubation practices, and hospital mortality. We used descriptive statistics to summarize variables with subgroup differences examined using t tests, z tests, or chi-squared tests where appropriate with 95% CIs.

RESULTS

Of 1720 patients with suspected COVID-19 who were intubated in the ED during the study period, 337 (19.6%) tested SARS-CoV-2 positive and 1383 (80.4%) SARS-CoV-2 negative. SARS-CoV-2 positive patients presented to hospital with lower oxygen levels than SARS-CoV-2 negative patients (mean pulse oximeter SaO2 86 vs 94%, p < 0.001). In total, 8.5% of patients experienced an adverse event post-intubation. More patients in the SARS-CoV-2 positive subgroup experienced post-intubation hypoxemia (4.5 vs 2.2%, p = 0.019). In-hospital mortality was greater for patients who experienced intubation-related adverse events (43.2 vs 33.2%, p = 0.018). There was no significant difference in adverse event-associated mortality by SARS-CoV-2 status. First-pass success was achieved in 92.4% of all intubations, with no difference by SARS-CoV-2 status.

CONCLUSIONS

During the COVID-19 pandemic, we observed a low risk of adverse events associated with intubation, even though hypoxemia was common in patients with confirmed SARS-CoV-2. We observed high rates of first-pass success and low rates of inability to intubate. The limited number of adverse events precluded multivariate adjustments. Study findings should reassure emergency medicine practitioners that system modifications made to intubation processes in response to the COVID-19 pandemic do not appear to be associated with worse outcomes compared to pre-COVID-19 practices.

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.