Placing an endotracheal tube is a life-saving measure. Direct laryngoscopy (DL) is traditionally the default method. Video laryngoscopy (VL) has been shown to improve efficiency, but there is insufficient evidence comparing VL versus DL in the prehospital settings. This study, comprising a systematic review and random-effects meta-analysis, assesses current literature for the efficacy of VL in prehospital settings.

PubMed and Scopus databases were searched from their beginnings through March 1, 2022 for eligible studies. Outcomes were the first successful intubation, overall success rate, and number of total DL versus VL attempts in real-life clinical situations. Cochrane’s Risk of Bias (RoB) tool and the Newcastle-Ottawa Scale (NOS) were applied to assess risk of bias and study quality; Q-statistics and I2 values were used to assess heterogeneity.

The search yielded seven studies involving 23,953 patients, 6,674 (28%) of whom underwent intubation via VL. Compared to DL, VL was associated with a statistically higher risk ratio for first-pass success (Risk Ratio [RR] = 1.116; 95% CI, 1.005-1.239; P = .041; I2 = 87%). The I2 value for the subgroup of prospective studies was 0% compared to 89% for retrospective studies. In addition, VL was associated with higher likelihood of overall success rate (RR = 1.097; 95% CI, 1.01-1.18; P = .021; I2 = 85%) and lower mean number of attempts (Mean Difference = -0.529; 95% CI, -0.922 to -0.137; P = .008).

The meta-analysis suggested that VL was associated with higher likelihood of achieving first-pass success, greater overall success rate, and lower number of intubation attempts for adults in the prehospital settings. This study had high heterogeneity, likely presenced by the inclusion of retrospective observational studies. Further studies with more rigorous methodology are needed to confirm these results.

Airway management is a controversial topic in modern Emergency Medical Services (EMS) systems. Among many concerns regarding endotracheal intubation (ETI), unrecognized esophageal intubation and observations of unfavorable neurologic outcomes in some studies raise the question of whether alternative airway techniques should be first-line in EMS airway management protocols. Supraglottic airway devices (SADs) are simpler to use, provide reliable oxygenation and ventilation, and may thus be an alternative first-line airway device for paramedics. In 2019, Alachua County Fire Rescue (ACFR; Alachua, Florida USA) introduced a novel protocol for advanced airway management emphasizing first-line use of a second-generation SAD (i-gel) for patients requiring medication-facilitated airway management (referred to as “rapid sequence airway” [RSA] protocol).

This was a one-year quality assurance review of care provided under the RSA protocol looking at compliance and first-pass success rate of first-line SAD use.

Records were obtained from the agency’s electronic medical record (EMR), searching for the use of the RSA protocol, advanced airway devices, or either ketamine or rocuronium. If available, hospital follow-up data regarding patient condition and emergency department (ED) airway exchange were obtained.

During the first year, 33 advanced airway attempts were made under the protocol by 23 paramedics. Overall, compliance with the airway device sequence as specified in the protocol was 72.7%. When ETI was non-compliantly used as first-line airway device, the first-pass success rate was 44.4% compared to 87.5% with adherence to first-line SAD use. All prehospital SADs were exchanged in the ED in a delayed fashion and almost exclusively per physician preference alone. In no case was the SAD exchanged for suspected dislodgement evidenced by lack of capnography.

First-line use of a SAD was associated with a high first-pass attempt success rate in a real-life cohort of prehospital advanced airway encounters. No SAD required emergent exchange upon hospital arrival.

Hazardous material (HAZMAT) protocols require health care providers to wear personal protective equipment (PPE) when caring for contaminated patients. Multiple levels of PPE exist (level D - level A), providing progressively more protection. Emergent endotracheal intubation (ETI) of victims can become complicated by the cumbersome nature of PPE.

The null hypothesis was tested that there would be no difference in time to successful ETI between providers in different types of PPE.

This randomized controlled trial assessed time to ETI with differing levels of PPE. Participants included 18 senior US Emergency Medicine (EM) residents and attendings, and nine US senior Anesthesiology residents. Each individual performed ETI on a mannequin (Laerdal SimMan Essential; Stavanger, Sweden) wearing the following levels of PPE: universal precautions (UP) controls (nitrile gloves and facemask with shield); partial level C (PC; rubber gloves and a passive air-purifying respirator [APR]); and complete level C (CC; passive APR with an anti-chemical suit). Primary outcome measures were the time in seconds (s) to successful intubation: Time 1 (T1) = inflation of the endotracheal tube (ETT) balloon; Time 2 (T2) = first ventilation. Data were reported as medians with Interquartile Ranges (IQR, 25%-75%) or percentages with 95% Confidence Intervals (95%, CI). Group comparisons were analyzed by Fisher’s Exact Test or Kruskal-Wallis, as appropriate (alpha = 0.017 [three groups], two-tails). Sample size analysis was based upon the power of 80% to detect a difference of 10 seconds between groups at a P = .017; 27 subjects per group would be needed.

All 27 participants completed the study. At T1, there was no statistically significant difference (P = .27) among UP 18.0s (11.5s-19.0s), PC 21.0s (14.0s-23.5s), or CC 17.0s (13.5s-27.5s). For T2, there was also no significant (P = .25) differences among UP 24.0s (17.5s-27.0s), PC 26.0s (21.0s-32.0s), or CC 24.0s (19.5s-33.5s).

There were no statistically significant differences in time to balloon inflation or ventilation. Higher levels of PPE do not appear to increase time to ETI.

Emergency Medical Services (EMS) providers are trained to place endotracheal tubes (ETTs) in the prehospital setting when indicated. Endotracheal tube cuffs are traditionally inflated with 10cc of air to provide adequate seal against the tracheal lumen. There is literature suggesting that many ETTs are inflated well beyond the accepted safe pressures of 20-30cmH2O, leading to potential complications including ischemia, necrosis, scarring, and stenosis of the tracheal wall. Currently, EMS providers do not routinely check ETT cuff pressures. It was hypothesized that the average ETT cuff pressure of patients arriving at the study site who were intubated by EMS exceeds the safe pressure range of 20-30cmH2O.

While ETT cuff inflation is necessary to close the respiratory system, thus preventing air leaks and aspiration, there is evidence to suggest that over-inflated ETT cuffs can cause long-term complications. The purpose of this study is to characterize the cuff pressures of ETTs placed by EMS providers.

This project was a single center, prospective observational study. Endotracheal tube cuff pressures were measured and recorded for adult patients intubated by EMS providers prior to arrival at a large, urban, tertiary care center over a nine-month period. All data were collected by respiratory therapists utilizing a cuff pressure measurement device which had a detectable range of 0-100cmH2O and was designed as a syringe. Results including basic patient demographics, cuff pressure, tube size, and EMS service were recorded.

In total, 45 measurements from six EMS services were included with ETT sizes ranging from 6.5-8.0mm. Mean patient age was 52.2 years (67.7% male). Mean cuff pressure was 81.8cmH2O with a range of 15 to 100 and a median of 100. The mode was 100cmH2O; 40 out of 45 (88.9%) cuff pressures were above 30cmH2O. Linear regression showed no correlation between age and ETT cuff pressure or between ETT size and cuff pressure. Two-tailed T tests did not show a significant difference in the mean cuff pressure between female versus male patients.

An overwhelming majority of prehospital intubations are associated with elevated cuff pressures, and cuff pressure monitoring education is indicated to address this phenomenon.

The Advanced Cardiac Life Support (ACLS) guidelines were recently updated to include ultrasound confirmation of endotracheal tube (ETT) location as an adjunctive tool to verify placement. While this method is employed in the emergency department under the guidance of the most recent American College of Emergency Physicians (ACEP; Irving, Texas USA) guidelines, it has yet to gain wide acceptance in the prehospital setting where it has the potential for greater impact. The objective of this study to is determine if training critical care medics using simulation was a feasible and reliable method to learn this skill.

Twenty critical care paramedics with no previous experience with point-of-care ultrasound volunteered for advanced training in prehospital ultrasound. Four ultrasound fellowship trained emergency physicians proctored two three-hour training sessions. Each session included a brief introduction to ultrasound “knobology,” normal sonographic neck and lung anatomy, and how to identify ETT placement within the trachea or esophagus. Immediately following this, the paramedics were tested with five simulated case scenarios using pre-obtained images that demonstrated a correctly placed ETT, an esophageal intubation, a bronchial intubation, and an improperly functioning ETT. Their accuracy, length of time to respond, and comfort with using ultrasound were all assessed.

All 20 critical care medics completed the training and testing session. During the five scenarios, 37/40 (92.5%) identified the correct endotracheal placements, 18/20 (90.0%) identified the esophageal intubations, 18/20 (90.0%) identified the bronchial intubation, and 20/20 (100.0%) identified the ETT malfunctions correctly. The average time to diagnosis was 10.6 seconds for proper placement, 15.5 seconds for esophageal, 15.6 seconds for bronchial intubation, and 11.8 seconds for ETT malfunction.

The use of ultrasound to confirm ETT placement can be effectively taught to critical care medics using a short, simulation-based training session. Further studies on implementation into patient care scenarios are needed.

Routine advanced airway usage by Emergency Medical Services (EMS) has had conflicting reports of being the secure airway of choice in pediatric patients.

The primary objective was to describe a pediatric cohort requiring airway management upon their arrival directly from the scene to two pediatric emergency departments (PEDs). A secondary objective included assessing for associations in EMS airway management and patient outcomes.

Retrospective data from the health record were reviewed, including EMS reports, for all arrivals less than 18 years old to two PEDs who required airway support between May 2015 and July 2016. The EMS management was classified as basic (oxygen, continuous positive airway pressure [CPAP], or bag-valve-mask [BVM]) or advanced (supraglottic or endotracheal intubation [ETI]) based on EMS documentation. Outcomes included oxygenation as documented by receiving PED and hospital mortality.

In total, 104 patients with an average age 5.9 (SD=5.1) years and median EMS Glasgow Coma Scale (GCS) of nine (IQR 3-14) were enrolled. Basic management was utilized in 70% of patients (passive: n=49; CPAP: n=2; BVM: n=22). Advanced management was utilized in 30% of patients (supraglottic: n=4; ETI: n=27). Proper ETI placement was achieved in 48% of attempted patients, with 41% of patients undergoing multiple attempts. Inadequate oxygenation occurred in 18% of patients, including four percent of ETI attempts, nine percent of BVM patients, and 32% of passively managed patients. Adjusted for EMS GCS, medical patients undergoing advanced airway management experienced higher risk of mortality (risk-ratio [RR] 2.98; 95% CI, 1.18-7.56; P=.021).

With exception to instances where ETI is clearly indicated, BVM management is effective in pediatric patients who required airway support, with ETI providing no definitive protective factors. Most of the patients who exhibited inadequate oxygenation upon arrival to the PED received only passive oxygenation by EMS.

TweedJ, GeorgeT, GreenwellC, VinsonL.Prehospital Airway Management Examined at Two Pediatric Emergency Centers. Prehosp Disaster Med. 2018;33(5):532–538.

Rapid identification of esophageal intubations is critical to avoid patient morbidity and mortality. Continuous waveform capnography remains the gold standard for endotracheal tube (ETT) confirmation, but it has limitations. Point-of-care ultrasound (POCUS) may be a useful alternative for confirming ETT placement. The objective of this study was to determine the accuracy of paramedic-performed POCUS identification of esophageal intubations with and without ETT manipulation.

A prospective, observational study using a cadaver model was conducted. Local paramedics were recruited as subjects and each completed a survey of their demographics, employment history, intubation experience, and prior POCUS training. Subjects participated in a didactic session in which they learned POCUS identification of ETT location. During each study session, investigators randomly placed an ETT in either the trachea or esophagus of four cadavers, confirmed with direct laryngoscopy. Subjects then attempted to determine position using POCUS both without and with manipulation of the ETT. Manipulation of the tube was performed by twisting the tube. Descriptive statistics and logistic regression were used to assess the results and the effects of previous paramedic experience.

During 12 study sessions, from March 2014 through December 2015, 57 subjects participated, evaluating a total of 228 intubations: 113 tracheal and 115 esophageal. Subjects were 84.0% male, mean age of 39 years (range: 22 - 62 years), with median experience of seven years (range: 0.6 - 39 years). Paramedics correctly identified ETT location in 158 (69.3%) cases without and 194 (85.1%) with ETT manipulation. The sensitivity and specificity of identifying esophageal location without ETT manipulation increased from 52.2% (95% confidence interval [CI], 43.0-61.0) and 86.7% (95% CI, 81.0-93.0) to 87.0% (95% CI, 81.0-93.0) and 83.2% (95% CI, 0.76-0.90) after manipulation (P<.0001), without affecting specificity (P=.45). Subjects correctly identified 41 previously incorrectly identified esophageal intubations. Paramedic experience, previous intubations, and POCUS experience did not correlate with ability to identify tube location.

Paramedics can accurately identify esophageal intubations with POCUS, and manipulation improves identification. Further studies of paramedic use of dynamic POCUS to identify inadvertent esophageal intubations are needed.

LemaPC, O’BrienM, WilsonJ, St. JamesE, LindstromH, DeAngelisJ, CaldwellJ, MayP, ClemencyB.Avoid the Goose! Paramedic Identification of Esophageal Intubation by Ultrasound. Prehosp Disaster Med.2018;33(4):406–410

Endotracheal intubation (ETI) is a complex clinical skill complicated by the inherent challenge of providing care in the prehospital setting. Literature reports a low success rate of prehospital ETI attempts, partly due to the care environment and partly to the lack of consistent standardized training opportunities of prehospital providers in ETI.

The availability of a mobile simulation laboratory (MSL) to study clinically critical interventions is needed in the prehospital setting to enhance instruction and maintain proficiency. This report is on the development and validation of a prehospital airway simulator and MSL that mimics in situ care provided in an ambulance.

The MSL was a Type 3 ambulance with four cameras allowing audio-video recordings of observable behaviors. The prehospital airway simulator is a modified airway mannequin with increased static tongue pressure and a rigid cervical collar. Airway experts validated the model in a static setting through ETI at varying tongue pressures with a goal of a Grade 3 Cormack-Lehane (CL) laryngeal view. Following completion of this development, the MSL was launched with the prehospital airway simulator to distant communities utilizing a single facilitator/driver. Paramedics were recruited to perform ETI in the MSL, and the detailed airway management observations were stored for further analysis.

Nineteen airway experts performed 57 ETI attempts at varying tongue pressures demonstrating increased CL views at higher tongue pressures. Tongue pressure of 60 mm Hg generated 31% Grade 3/4 CL view and was chosen for the prehospital trials. The MSL was launched and tested by 18 paramedics. First pass success was 33% with another 33% failing to intubate within three attempts.

The MSL created was configured to deliver, record, and assess intubator behaviors with a difficult airway simulation. The MSL created a reproducible, high fidelity, mobile learning environment for assessment of simulated ETI performance by prehospital providers.

BischofJJ, PanchalAR, FinneganGI, TerndrupTE. Creation and Validation of a Novel Mobile Simulation Laboratory for High Fidelity, Prehospital, Difficult Airway Simulation. Prehosp Disaster Med. 2016;31(5):465–470.