Airway management is a cornerstone in the prehospital care of critically ill or injured patients. Surgical cricothyrotomy offers a rapid and effective solution when oxygenation and ventilation fail using less-invasive techniques. However, the exact indications, incidence, and success of prehospital surgical cricothyrotomy are unknown, with variable rates reported in the literature. This study aimed to examine prehospital indications and success rates for surgical cricothyrotomy within a large, suburban, ground-based Emergency Medical Services (EMS) system.

This is a retrospective analysis of 31 patients who underwent paramedic performed surgical cricothyrotomy from 2012 through 2022. Key demographic parameters were analyzed, including the incidence of cardiac arrest, call type (trauma versus medical), initial airway management attempts, number of endotracheal intubation (ETI) attempts before surgical airway, and average time to the establishment of a surgical airway in relation to the number of ETI attempts. Surgical cricothyrotomy success was defined as the acquisition of four-phase end-tidal capnography reading. The primary data sources were the EMS electronic medical records, and descriptive statistics were calculated.

A total of 31 patients were included in the final analysis. Of those who received a surgical cricothyrotomy, 42% (13/31) occurred in the trauma setting, while 58% (18/31) were medical calls. In all patients who underwent surgical cricothyrotomy, the median (IQR) time to the procedure was 17 minutes (IQR = 11-24). In trauma patients, the median time to surgical cricothyrotomy was 12 minutes (IQR = 9-19) versus 19 minutes (IQR = 14-33) in medical patients. End-tidal carbon dioxide (ETCO2) detection and placement success was confirmed in 94% (29/31) of patients. Endotracheal intubation was attempted in 55% (17/31) before subsequent surgical cricothyrotomy, with 29% (9/31) receiving more than one ETI attempt. The median time to surgical cricothyrotomy when multiple prior intubation attempts occurred was 33 minutes (IQR = 23-36) compared to 14.5 minutes (IQR = 6-19) in patients without a preceding intubation attempt.

Prehospital surgical airway can be performed by paramedics with a high degree of success. Identification of the need for surgical cricothyrotomy should be determined as soon as possible to allow for rapid securement of the airway and to ensure adequate oxygenation and ventilation.

Prehospital pediatric intubation is a potentially life-saving procedure in which paramedics are relied upon. However, due to the anatomical nature of pediatrics and associated adverse events, it is more challenging compared to adult intubation. In this study, the knowledge and attitude of paramedics was assessed by measuring their overall success rate and associated complications.

An online search using PubMed, Scopus, Web of Science, and Cochrane CENTRAL was conducted using relevant keywords to include studies that assess success rates and associated complications. Studies for eligibility were screened. Data were extracted from eligible studies and pooled as risk ratio (RR) with a 95% confidence interval (CI).

Thirty-eight studies involving 14,207 pediatrics undergoing intubation by paramedics were included in this study. The prevalence of success rate was 82.5% (95% CI, 0.745-0.832) for overall trials and 77.2% (95% CI, 0.713-0.832) success rate after the first attempt. By subgrouping the patients according to using muscle relaxants during intubation, the group that used muscle relaxants showed a high overall successful rate of 92.5% (95% CI, 0.877-0.973) and 79.9% (95% CI, 0.715-0.994) success rate after the first attempt, more than the group without muscle relaxant which represent 78.9% (95% CI, 0.745-0.832) overall success rate and 73.3% (95% CI, 0.616-0.950) success rate after first attempt.

Paramedics have a good overall successful rate of pediatric intubation with a lower complication rate, especially when using muscle relaxants.

Hypoxia is a frequently reported complication during the intubation procedure in the emergency department (ED) and may cause bad outcomes. Therefore, oxygenation plays an important role in emergency airway management. The efficacy of oxygenation with high-flow nasal cannula (HFNC) in the ED has been studied, though the evidence is limited. The study aim was to compare two methods of preoxygenation in patients undergoing rapid sequence intubation (RSI) in the ED: (1) HFNC and (2) bag-valve mask (BVM) oxygenation.

This is a single-center, prospective, randomized controlled trial (RCT) in adult ED patients requiring RSI. Patients were randomized to receive preoxygenation with either HFNC or BVM. While HFNC therapy was continued during the intubation procedure, BVM oxygenation was interrupted for laryngoscopy. The primary outcome was the lowest peripheral oxygen saturation (SpO2) level during intubation. Secondary outcomes were incidence of desaturation (SpO2<90%) and severe hypoxemia (SpO2<80%) throughout the procedure, intubation time, rate of failed intubation, and 30-day survival rates.

A total of 135 patients were randomized into two groups (HFNC n = 68; BVM n = 67). The median lowest SpO2 value measured during intubation was 96% (88.8%-99.0%) in the HFNC group and 92% (86.0%-97.5%) in the BVM group (P = .161). During the intubation procedure, severe hypoxemia occurred in 13.2% (n = 9) of patients in the HFNC group and 8.9% (n = 6) in the BVM group, while mild hypoxemia was observed in 35.8% (n = 24) of the BVM group and 26.5% (n = 18) of the HFNC group. However, there was no statistically significant difference between the groups in terms of hypoxemia development (P = .429 and P = .241, respectively). No significant difference was reported in the rate of failed intubation between the groups. Thirty-day mortality was observed in 73.1% of the BVM group and 57.4% of the HFNC group, with a borderline statistically significant difference (difference 15.7; 95% CI of the difference: −0.4 to 30.7; P = .054).

The use of HFNC for preoxygenation, when compared to standard care with BVM oxygenation, did not improve the lowest SpO2 levels during intubation. Also, the use of HFNC during intubation did not provide benefits in reducing the incidence of severe hypoxemia. However, the 30-day survival rates were slightly better in the HFNC group compared to the BVM group.

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.

The management of out-of-hospital traumatic cardiac arrest (TCA) for professional rescuers entails Advanced Life Support (ALS) with specific actions to treat the potential reversible causes of the arrest: hypovolemia, hypoxemia, tension pneumothorax (TPx), and tamponade. The aim of this study was to assess the impact of specific rescue measures on short-term outcomes in the context of resuscitating patients with a TCA.

This retrospective study concerns all TCA patients treated in two emergency medical units, which are part of the Northern French Alps Emergency Network (RENAU), from January 2004 through December 2017. Utstein variables and specific rescue measures in TCA were compiled: fluid expansion, pelvic stabilization, tourniquet application, bilateral thoracostomy, and thoracotomy procedures. The primary endpoint was survival rate at Day 30 with good neurological status (Cerebral Performance Category [CPC] score CPC 1 and CPC 2).

In total, 287 resuscitation attempts in TCA were included and 279 specific interventions were identified: 262 fluid expansions, 41 pelvic stabilizations, five tourniquets, and 175 bilateral thoracostomies (including 44 with TPx).

Among the standard resuscitation measures to treat the reversible causes of cardiac arrest, this study found that bilateral thoracostomy and tourniquet application on a limb hemorrhage improve survival in TCA. A larger sample for pelvic stabilization is needed.

Securing the airway is a crucial stage of trauma care. Cricothyroidotomy (CRIC) is often addressed as a salvage procedure in complicated cases or following a failed endotracheal intubation (ETI). Nevertheless, it is a very important skill in prehospital settings, such as on the battlefield.

This study aimed to review the Israel Defense Forces (IDF) experience with CRIC over the past two decades.

The IDF Trauma Registry (IDF-TR) holds data on all trauma casualties (civilian and military) cared for by military medical teams since 1997. Data of all casualties treated by IDF from 1998 through 2018 were extracted and analyzed to identify all patients who underwent CRIC procedures.

Variables describing the incident scenario, patient’s characteristics, injury pattern, treatment, and outcome were extracted. The success rate of the procedure was described, and selected variables were further analyzed and compared using the Fisher’s-exact test to identify their effect on the success and failure rates. Odds Ratio (OR) was further calculated for the effect of different body part involvement on success and for the mortality after failed ETI.

One hundred fifty-three casualties on which a CRIC attempt was made were identified from the IDF-TR records. The overall success rate of CRIC was reported at 88%. In patients who underwent one or two attempts, the success rate was 86%. No difference was found across providers (physician versus paramedic). The CRIC success rates for casualties with and without head trauma were 80% and 92%, respectively (P = .06). Overall mortality was 33%.

This study shows that CRIC is of merit in airway management as it has shown to have consistently high success rates throughout different levels of training, injuries, and previous attempts with ETI. Care providers should be encouraged to retain and develop this skill as part of their tool box.

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.

The 2017 International Liaison Committee on Resuscitation (ILCOR) guideline recommends that Emergency Medical Service (EMS) providers can perform cardiopulmonary resuscitation (CPR) with synchronous or asynchronous ventilation until an advanced airway has been placed. In the current literature, limited data on CPR performed with continuous compressions and asynchronous ventilation with bag-valve-mask (BVM) are available.

In this study, researchers aimed to compare the effectiveness of asynchronous BVM and laryngeal mask airway (LMA) ventilation during CPR with continuous chest compressions.

Emergency medicine residents and interns were included in the study. The participants were randomly assigned to resuscitation teams with two rescuers. The cross-over simulation study was conducted on two CPR scenarios: asynchronous ventilation via BVM during a continuous chest compression and asynchronous ventilation via LMA during a continuous chest compression in cardiac arrest patient with asystole. The primary endpoints were the ventilation-related measurements.

A total of 92 volunteers were included in the study and 46 CPRs were performed in each group. The mean rate of ventilations of the LMA group was significantly higher than that of the BVM group (13.7 [11.7-15.7] versus 8.9 [7.5-10.3] breaths/minute; P <.001). The mean volume of ventilations of the LMA group was significantly higher than that of the BVM group (358.4 [342.3-374.4] ml versus 321.5 [303.9-339.0] ml; P = .002). The mean minute ventilation volume of the LMA group was significantly higher than that of the BVM group (4.88 [4.15-5.61] versus 2.99 [2.41-3.57] L/minute; P <.001). Ventilations exceeding the maximum volume limit occurred in two (4.3%) CPRs in the BVM group and in 11 (23.9%) CPRs in the LMA group (P = .008).

The results of this study show that asynchronous BVM ventilation with continuous chest compressions is a reliable and effective strategy during CPR under simulation conditions. The clinical impact of these findings in actual cardiac arrest patients should be evaluated with further studies at real-life scenes.

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.

The primary goal of this study was to compare paramedic first pass success rate between two different video laryngoscopes and direct laryngoscopy (DL) under simulated prehospital conditions in a cadaveric model.

This was a non-randomized, group-controlled trial in which five non-embalmed, non-frozen cadavers were intubated under prehospital spinal immobilization conditions using DL and with both the GlideScope Ranger (GL; Verathon Inc, Bothell, Washington USA) and the VividTrac VT-A100 (VT; Vivid Medical, Palo Alto, California USA). Participants had to intubate each cadaver with each of the three devices (DL, GL, or VT) in a randomly assigned order. Paramedics were given 31 seconds for an intubation attempt and a maximum of three attempts per device to successfully intubate each cadaver. Confirmation of successful endotracheal intubation (ETI) was confirmed by one of the six on-site physicians.

Successful ETI within three attempts across all devices occurred 99.5% of the time overall and individually 98.5% of the time for VT, 100.0% of the time for GL, and 100.0% of the time for DL. First pass success overall was 64.4%. Individually, first pass success was 60.0% for VT, 68.8% for GL, and 64.5% for DL. A chi-square test revealed no statistically significant difference amongst the three devices for first pass success rates (P=.583). Average time to successful intubation was 42.2 seconds for VT, 38.0 seconds for GL, and 33.7 for seconds for DL. The average number of intubation attempts for each device were as follows: 1.48 for VT, 1.40 for GL, and 1.42 for DL.

The was no statistically significant difference in first pass or overall successful ETI rates between DL and video laryngoscopy (VL) with either the GL or VT (adult).

HodnickR, ZitekT, GalsterK, JohnsonS, BledsoeB, EbbsD. A Comparison of Paramedic First Pass Endotracheal Intubation Success Rate of the VividTrac VT-A 100, GlideScope Ranger, and Direct Laryngoscopy Under Simulated Prehospital Cervical Spinal Immobilization Conditions in a Cadaveric Model. Prehosp Disaster Med. 2017;32(6):621–624.

The goal of this study was to compare the relative effectiveness of three adjunctive maneuvers – head elevation (HE), forward laryngoscope traction (FT), and external laryngeal manipulation (ELM) – on laryngoscopic view, intubation time, and intubation success performed by a sample of novice intubators using a simulated airway.

Twenty-two second year university paramedic students were required to perform laryngoscopy and intubation on a simulator four times on two separate days. The first day involved intubation using no adjunctive maneuvers (control) plus HE, FT, and ELM in random order in a normal simulated airway. A similar approach was used on the second day, but the simulator was configured to have a difficult airway. Percentage of glottic opening (POGO) scores, intubation time, and intubation success were measured for all intubation attempts.

Head elevation was found to be the most effective adjunctive maneuver in the normal airway, increasing the mean POGO score from control by 27% (P=.002), while ELM was most effective in the difficult airway, increasing the mean POGO score by 21% (P=.009) and the proportion of successful intubations by 41% (P<.001). All maneuvers decreased intubation time in the normal and difficult airway and were associated with significant differences in intubation success compared to control in the difficult airway.

This study identified HE as the most effective maneuver for improving laryngoscopic view in a normal airway and ELM as the most effective in a difficult airway in a group of novice intubators.

SteinC, GerberL, CurtinD, OberemN, WellsM. A Comparison of Three Maneuvers and Their Effect on Laryngoscopic View, Time to Intubate, and Intubation Outcome by Novice Intubators in a Simulated Airway. Prehosp Disaster Med. 2017;32(4):419–423.

Vasopressors are associated with return of spontaneous circulation (ROSC), but no long-term benefit has been demonstrated in randomized trials. However, these trials did not control for the timing of vasopressor administration which may influence outcomes. Consequently, the objective of this study was to develop a model describing the likelihood of favorable neurological outcome (cerebral performance category [CPC] 1 or 2) as a function of the public safety answering point call receipt (PSAP)-to-pressor-interval (PPI) in prolonged out-of-hospital cardiac arrest.

The likelihood of favorable neurological outcome declines with increasing PPI.

This investigation was a retrospective study of cardiac arrest using linked data from the Cardiac Arrest Registry to Enhance Survival (CARES) database (Centers for Disease Control and Prevention [Atlanta, Georgia USA]; American Heart Association [Dallas, Texas USA]; and Emory University Department of Emergency Medicine [Atlanta, Georgia USA]) and the North Carolina (USA) Prehospital Medical Information System. Adult patients suffering a bystander-witnessed, non-traumatic cardiac arrest between January 2012 and June 2014 were included. Logistic regression was used to calculate the adjusted odds ratio (OR) of neurological outcome as a function of PPI, while controlling for patient age, gender, and race; endotracheal intubation (ETI); shockable rhythm; layperson cardiopulmonary resuscitation (CPR); and field hypothermia.

Of the 2,100 patients meeting inclusion criteria, 913 (43.5%) experienced ROSC, 618 (29.4%) survived to hospital admission, 187 (8.9%) survived to hospital discharge, and 155 (7.4%) were discharged with favorable neurological outcomes (CPC 1 or 2). Favorable neurological outcome was less likely with increasing PPI (OR=0.90; P<.01) and increasing age (OR=0.97; P<.01). Compared to patients with non-shockable rhythms, patients with shockable rhythms were more likely to have favorable neurological outcomes (OR=7.61; P<.01) as were patients receiving field hypothermia (OR=2.13; P<.01). Patient gender, non-Caucasian race, layperson CPR, and ETI were not independent predictors of favorable neurological outcome.

In this evaluation, time to vasopressor administration was significantly associated with favorable neurological outcome. Among adult, witnessed, non-traumatic arrests, the odds of hospital discharge with CPC 1 or 2 declined by 10% for every one-minute delay between PSAP call-receipt and vasopressor administration. These retrospective observations support the notion of a time-dependent function of vasopressor effectiveness on favorable neurological outcome. Large, prospective studies are needed to verify this relationship.

HubbleMW, TysonC. Impact of Early Vasopressor Administration on Neurological Outcomes after Prolonged Out-of-Hospital Cardiac Arrest. Prehosp Disaster Med. 2017; 32(3):297–304.

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.

To evaluate the effect of body mass index and neck length on endotracheal tube movement during neck extension in thyroidectomy.

A prospective study was conducted of 30 patients undergoing thyroidectomy during an 8-month period. Patient characteristics were recorded and endotracheal tube displacement was determined.

Mean body mass index was 27.8 kg/m2 (range, 17.5–34.7 kg/m2) and mean neck circumference was 43.2 cm (range, 28–56 cm). The mean (± standard deviation) upward displacement of the endotracheal tube during neck extension was 7.17 ± 5.87 mm. Patients with a larger body mass index had a significantly greater amount of tube displacement (R2 = 0.67, p < 0.0001), as did patients with a smaller neck length (R2 = 0.48, p < 0.0001).

Neck extension results in upward displacement of the endotracheal tube. The amount of displacement is significantly higher in patients with a larger body mass index or shorter neck length. This has particular relevance for nerve monitoring in thyroidectomy.