Integrating Rapid Cardiopulmonary and Gastric Ultrasound for Emergency Airway Management in Critically Ill Patients: A Case Series of Resident-Performed Echocardiographic Assessment Using Subcostal-Only-View in Physiologically Difficult Airway

Abstract

OBJECTIVES:

Tracheal intubation in critically ill patients is associated with significant morbidity and mortality. Point-of-care ultrasound (POCUS) may help with hemodynamic optimization and customization of management plans to the patient’s tenuous physiology to prevent cardiopulmonary collapse. We report the integration of POCUS in the emergency airway management (EAM) of critically ill patients at a tertiary care academic medical center.

DESIGN:

Our study is a retrospective, exploratory research project. We evaluated the feasibility of using Echocardiography Assessment using Subcostal-only-view in Physiologically Difficult Airway (EASy-PDA) protocol to prevent peri-intubation hemodynamic compromise during EAM.

SETTING:

This study took place at a tertiary academic medical center where requests for EAM were answered by anesthesiologists.

SUBJECTS:

The EASy-PDA protocol was performed on 30 patients with PDA outside of the operating room in need of EAM.

INTERVENTIONS:

The EASy-PDA protocol included the acquisition of subcostal four-chamber (SC4C) and inferior vena cava (IVC) images, supplemented by focused lung and gastric ultrasonography. Trained anesthesiology residents performed EASy-PDA examinations before airway management, and subsequently assigned hemodynamic phenotypes based on qualitative assessment of biventricular chamber size, myocardial wall thickness and function, and IVC size and collapsibility. Management was then tailored based on hemodynamic phenotyping.

MEASUREMENTS AND MAIN RESULTS:

The mean time to complete the EASy-PDA examination was 2.40 minutes. SC4C image could not be obtained in one patient due to severe abdominal pain. Images obtained solely via the EASy-PDA examination were sufficient to inform further patient management in 26 patients (86.7%), with one patient requiring emergent pericardial window creation and two patients requiring gastric decompression before intubation based on examination findings.

CONCLUSIONS:

We were able to show the feasibility of integrating the EASy-PDA protocol into the management of emergent airways. In our case series, we observed that the EASy-PDA examination findings guided hemodynamic optimization before EAM in critically ill patients. This approach may help reduce intubation-associated morbidity and mortality. Further studies are needed to assess the impact of integration of EASy protocol during EAM on patient outcomes.

KEY POINTS

Question: We investigated the feasibility of integrating a novel point-of-care ultrasound protocol into emergency airway management (EAM) and its impact on hemodynamic management.

Findings: In this retrospective pilot evaluation of a novel diagnostic process, we found that ultrasound images obtained solely via our Echocardiography Assessment using Subcostal-only-view in Physiologically Difficult Airway (EASy-PDA) protocol were sufficient to inform interventions in most patients.

Meanings: Our findings demonstrate the feasibility of implementing the EASy-PDA protocol during EAM to optimize patient hemodynamics and provide a basis for future studies evaluating the effectiveness of the EASy-PDA protocol in the management of a PDA.

Tracheal intubation is one of the most frequently performed procedures in critically ill patients and is associated with significant morbidity and mortality. The International Observational Study To Understand The Impact And Best Practices Of Airway Management In Critically Ill Patients (INTUBE) study found that peri-intubation cardiovascular instability occurred in 43% of patients, and 3% of the patients suffered a cardiac arrest. The 28-day mortality rate for patients who experienced peri-intubation hemodynamic instability was higher at 37.5% compared with 24.6% for those without hemodynamic instability (1). Most critically ill patients tend to have a physiologically difficult airway (PDA), wherein their physiologic derangements predispose them to an increased risk of complications and poor outcomes during intubation and initiation of positive pressure ventilation (2, 3). The lack of sufficient diagnostic information for such patients often hampers hemodynamic optimization before and during this high-risk procedure.

Point-of-care ultrasound (POCUS) has become increasingly common in the management of acutely ill patients over the last decades and has shown promising results in identifying causes of respiratory and circulatory failure (4, 5), decreasing the time to administration of treatment, and possibly improving survival of patients on the wards who develop acute respiratory or circulatory failure (6–9). The potential role of POCUS in optimizing patients before emergency airway management (EAM) has recently been reviewed (10). The time-sensitivity in these settings and the inability to obtain certain echocardiographic views require an algorithmic approach to POCUS assessment that is efficient and easy to interpret. The Echocardiography Assessment using Subcostal-only-view in PDA (EASy-PDA) examination protocol is a novel ultrasonographic assessment method that consists of a subxiphoid four-chamber cardiac and inferior vena cava (IVC) view, supplemented with examination of the upper lung fields, pleural spaces, and gastric antrum. This allows for hemodynamic phenotyping as well as assessment for a full stomach before intubation. The EASy-PDA examination can be used in time-sensitive settings or when multiple echocardiographic views are unobtainable, with interpretation guided by recognizing certain hemodynamic patterns (phenotypes). The EASy-PDA examination provides sufficient information in most patients to narrow the differential diagnosis of hemodynamic instability via the determination of biventricular function and intravascular volume status (10, 11).

We have previously shown that diagnostic information to assess patients’ hemodynamic instability or to define volume status in the perioperative setting is comparable between the EASy examination and the more extensive focused transthoracic echocardiography (FTTE) (11). We have also demonstrated that residents were able to perform the EASy examination in a short time (12). Additionally, we described the feasibility of integrating the EASy examination in the Advanced Life Support algorithm during the pulse and rhythm check to help perform targeted interventions during the resuscitation process (13). These preceding studies demonstrated the success of the EASy protocol for rapid cardiopulmonary assessment in time-sensitive settings. However, a knowledge gap exists regarding the use of the EASy examination in the pre-tracheal intubation setting to optimize patients’ hemodynamic status. This EASy-PDA study was conducted to assess the feasibility of integrating POCUS into the workflow of EAM at a tertiary care academic medical center through identification of high-risk cardiopulmonary phenotypes and subsequent hemodynamic optimization.

METHODS

In this exploratory research project, we assessed the feasibility of integrating the EASy examination during EAM in critically ill patients. We reviewed the records of all patients who had the EASy-PDA examination performed before EAM between the dates from June 1, 2019, to March 1, 2023. The Institutional Review Board (No. 6504) approved this study, Pre-Induction Hemodynamic Phenotyping of Patients using the Echocardiographic Assessment with Subxiphoid only (EASy) Exam on April 21, 2022. The requirement for written informed consent was waived. Procedures were followed in accordance with the ethical standards of our institutional committee for human experimentation and the Helsinki Declaration of 1975.

Clinical Setting

At the study institution, requests for EAM in the ICU or medical and surgical floors are made to an airway team. This team is comprised of an attending anesthesiologist, anesthesiology resident or certified registered nurse anesthetist, respiratory therapist, and critical care nurse. The EASy-PDA examination was performed on patients requiring EAM outside of the operating room. The examination was performed by residents only when specific attendings with expertise in POCUS (N.F.B., A.R.) were the responding anesthesiologists and bedside ultrasound was available.

At this study institution, the standard of care for EAM is induction using propofol without preemptive IV fluid bolus or vasopressor administration. For patients with known cardiac systolic dysfunction, induction was performed using etomidate without preemptive IV fluid bolus or vasopressors. Vasopressors are only used in response to hemodynamic instability. During the study period, the EASy-PDA examination was performed while the patient was being preoxygenated via bag-mask ventilation and intubation equipment were being prepared. Tracheal intubation was not delayed for the performance of POCUS. The examination was performed either by faculty experts in POCUS or a POCUS-trained anesthesiology resident under the direct supervision of a faculty physician.

Training Process for Residents Performing POCUS During EAM

At the study institution, all first-year anesthesiology residents undergo a 1-day POCUS training course. The didactic session is a 2-hour web-based curriculum led by a POCUS expert, a 1-hour question and answer session, and a 1-hour interactive presentation to provide structured training on the EASy phenotypes outlined below. During the hands-on training, residents complete ten EASy examinations under faculty supervision on ICU patients as part of their routine care, with an emphasis on image acquisition. Authorization to obtain POCUS images during patient care following course completion demonstrated a trainee’s proficiency in obtaining interpretable POCUS images and is not an indicator of full sonographic competency or ability to appropriately interpret images. In a previous study, we demonstrated that this training course was feasible in teaching residents to obtain images of adequate quality in 87% of examinations (12).

EASy Examination

The EASy examination primarily uses the subcostal window to capture views of the heart and the IVC, with supplemental assessment of the anterior lung field views, posterolateral diaphragmatic pleural recess, and gastric antrum (Fig. 1). POCUS examinations were performed using an XPorte ultrasound machine (FUJIFILM Sonosite, Bothell, WA) with a phased array transducer, with the depth set to 21 cm. This depth was standard for cardiac, IVC, and lung visualization and interpretation to minimize variability due to depth-related distortion in appearance. The examination was performed with patients in the supine position with the head of bed elevated to approximately 30°. This head-up position has been recommended for the management of a PDA (3) and also allows for safe and consistent POCUS image acquisition. The protocol begins with obtaining a subcostal four-chamber (SC4C) view of the heart, visualization of the IVC and the aorta, and rotation of the probe to obtain the midpapillary short-axis view of the heart (14) (Video 1; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567). While examining the aorta, the gastric antrum is viewed by rocking the probe tail up. Qualitative evaluation of the gastric antrum enables the user to identify significant antral content (Video 2; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567) that could impact airway safety if aspirated. Last, anterior lung images are obtained by placing the probe in the second intercostal space at the midclavicular line, and pleural images are obtained by placing the probe in the subcostal plane at right midaxillary and left posterior axillary lines (Video 1; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567). Studies were interpreted by the attending or by the resident under direct supervision of a POCUS-trained faculty member (Video 3; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567), and the findings were used in real time to guide hemodynamic management during EAM.

Figure 1.

Point-of-care ultrasound probe placement in Echocardiography Assessment using Subcostal-only-view (EASy) examinations. The EASy examination is comprised of views to perform cardiac, inferior vena cava, gastric, and pulmonary assessment. A, Subcostal four-chamber heart, inferior vena cava/aorta, and gastric antrum. B, Midpapillary short-axis heart. C and D, Apical lung. E and F, Posterolateral diaphragmatic pleural recess. Courtesy of N. Bughrara, MD, Albany, NY.

Hemodynamic Phenotyping

POCUS findings were characterized based on hemodynamic phenotypes with an emphasis on cardiac performance and fluid responsiveness, such as assessment of biventricular chamber size, thickness, and function, as well as IVC size and collapsibility as a surrogate for volume status. Patients were grouped into four primary clusters, which were further divided into ten distinct phenotypes, each suggesting a specific approach to clinical management (Figs. 2 and 3). Cluster 1 included phenotypes with normal or hyperdynamic left ventricular (LV) systolic function (Video 4; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567). Cluster 2 comprised of phenotypes indicating severe LV systolic dysfunction and dilation, with or without right ventricular (RV) dysfunction (Video 5; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567). Cluster 3 was associated with phenotypes including acute or acute on chronic severe, isolated RV dysfunction and dilation, where the RV is larger than the LV (Video 6; caption in the Supplemental Digital Content, https://links.lww.com/CCX/B567). In our protocol, cluster 3 classification requires both echocardiographic evidence of severe RV dilation (RV > LV in size) and a plethoric, noncollapsing IVC indicating elevated right-sided pressures and impaired RV forward flow. Cluster 3 reflects specific underlying pathophysiology and carries distinct management implications. Notably, these patients have demonstrated higher mortality in our institutional experience (15) and warrant tailored management strategies that emphasize preload optimization, careful afterload reduction, and avoidance of high intrathoracic pressures (Fig. 4). Patients who do not meet the explicit criteria for clusters 2 and 3, including those with normal, hyperdynamic, or mildly to moderately reduced LV dysfunction, and those with mildly enlarged RV, are classified under cluster 1 (Fig. 2). This is an intentional safeguard to avoid over-triaging patients with only borderline or uncertain reductions in function. Last, less common phenotypes of obstructive shock that require emergent surgical or procedural intervention, such as cardiac tamponade, large pleural effusion, catastrophic valvular pathologies, and tension pneumothorax or auto positive end-expiratory pressure, were categorized separately in cluster 4 (Fig. 3). Phenotype reference cards were placed directly on ultrasound machines for access.

Figure 2.

Common phenotypes found on Echocardiography Assessment using Subcostal-only-view (EASy) examination. EASy phenotypes are based on the subcostal four-chamber view (first row), subcostal inferior vena cava (IVC) view (second row), and lung evaluation in the upper lung fields (third row). Cardiac assessment assesses myocardial performance, IVC evaluation provides an estimate of fluid responsiveness, and lung examination defines fluid tolerance (A pattern) and intolerance (B pattern). Each phenotype is associated with a suspected underlying pathology (bottom row). Courtesy of N. Bughrara, MD, Albany, NY. ARDS = acute respiratory distress syndrome, Bi A = biatrial, Bi V = biventricular, HTN = hypertension, LA = left atrium, LV = left ventricle, LVH = left ventricular hypertrophy, RA = right atrium, RV = right ventricle, RVH = right ventricular hypertrophy.

Figure 3.

Less common phenotypes found on Echocardiography Assessment using Subcostal-only-view (EASy) examination. EASy phenotypes are based on the subcostal four-chamber view (first row), subcostal inferior vena cava (IVC) view (second row), and lung evaluation in the upper lung fields or lower lung fields for phenotype 8 (third row). Cardiac assessment assesses myocardial performance, IVC evaluation provides an estimate of fluid responsiveness, and lung examination defines fluid tolerance (A pattern), fluid intolerance (B pattern), or absent pleural sliding (phenotype 10). Each phenotype is associated with a suspected underlying pathology (bottom row). Courtesy of N. Bughrara, MD, Albany, NY. PEEP = positive end-expiratory pressure, RA = right atrium.

Figure 4.

Example of resuscitation of a patient with preexisting pulmonary hypertension (HTN) with right ventricular (RV) hypertrophy who developed acute respiratory distress syndrome (ARDS) and septic shock requiring tracheal intubation (cluster 3, phenotype 7). Initially, small fluid boluses 2.5 mL/kg at a time were provided until the inferior vena cava (IVC) became fuller and systemic mean arterial pressure (MAP) improved to greater than 65 mm Hg. On induction of anesthesia, intubation, and initiation of positive pressure ventilation (PPV) using a protective strategy with low tidal volumes (TVs) and titrated positive end-expiratory pressure (PEEP) and Fio₂, RV function became decompensated with bowing of the interventricular septum through the cardiac cycle toward the left ventricle (LV). At this point, vasoactive (vasopressin) and inotropic (epinephrine and milrinone) medications were added, and patient was started on a pulmonary vasodilator (inhaled prostacyclin). Pulse pressure variation readings are inaccurate in a patient with decompensated RV function and were not followed. In accordance with Surviving Sepsis Guidelines tissue, perfusion markers were followed throughout the case, and goals of resuscitation are stated in the box on the far right. Courtesy of N. Bughrara, MD, Albany, NY. FRC = functional residual capacity, iNO = inhaled nitric oxide, IVF = IV fluids, LA = left atrium, RA = right atrium, Svo₂ = mixed venous oxygen saturation, U/O = urine output.

Residents were responsible for obtaining images, while faculty proficient in POCUS were present at the bedside to review the images and lead interpretation and management. This setup was done to mitigate cognitive biases, including the Dunning-Kruger effect (16), where less experienced individuals may overestimate their abilities. Management decisions were based on phenotype identification and clinical context (Fig. 5). Once a decision was reached, findings were communicated to the team. This follows the I-AIM protocol of Indication, Acquisition, Interpretation, and Medical decision-making (17). This collaborative model emphasized team-based decision-making to ensure diagnostic accuracy, safety, and meaningful educational feedback for trainees.

Figure 5.

A systematic approach to patient optimization immediately before induction of anesthesia based on organization of ultrasound findings into phenotypes and clusters. The mainstay therapy for patients in cluster 1 includes fluid resuscitation, and as the inferior vena cava (IVC) becomes fuller, the therapy shifts toward vasoactive medications. These patients could be followed using serial Echocardiography Assessment using Subcostal-only-view examination and pulse pressure variation. Depending on IVC evaluation, patients in cluster 2 may benefit from small titrated fluid boluses 2.5–5 mL/kg (under conditions of collapsible IVC); however, the mainstay therapy usually consists of using vasoactive medications and occasionally inotropic agents when end-organ perfusion is not restored. In these patients, pulse pressure variation is of value, and additional evaluation of left ventricular (LV) diastolic function is appropriate if an expert is available. Patients in cluster 3 present particular challenges, and assessment of septal shift is required to establish whether right ventricular (RV) function is compensated or not (septum bows into the LV during diastole preventing adequate LV filling). Gentle fluid loading on a scale of 2.5 mL/kg can be provided when function is compensated, and measures such as diuresis or renal-replacement therapy when RV function is decompensated. The mainstay therapy includes maintenance of systemic blood pressure with vasoactive medications and inotropic support, and minimizing increases in pulmonary pressures by avoiding hypoxemia/hypercapnia and through the use of pulmonary vasodilators. Courtesy of N. Bughrara, MD, Albany, NY. IVF = IV fluid, LA = left atrium, NE = norepinephrine, PPV = positive pressure ventilation, RA = right atrium, RR = respiratory rate, TV = tidal volume.

IVC Assessment

IVC assessment was qualitative but guided by strict three-tiered classification to reduce subjectivity (Fig. 2). IVC type 1 represented a flat and collapsing IVC, with a maximal diameter less than 1 cm—indicative of hypovolemia in the absence of external IVC compression or abdominal hypertension. IVC type 3 represented a plethoric, dilated IVC with no respiratory variation—suggesting volume overload or elevated right-sided pressures. IVC type 2 represented any intermediate appearance that did not clearly meet criteria for type 1 or 3.

Our three-tier IVC classification system was used in conjunction with cardiac assessment to reduce the risk of oversimplification of physiologic variations in IVC size and collapsibility particularly in patients with respiratory failure. This enables a nuanced interpretation that accounts for the complex and overlapping physiologic states seen in critically ill patients. This rapid screening tool is meant to inform not replace clinical judgment and comprehensive evaluation.

Lung and Gastric Assessment

Lungs were evaluated based on the presence of lung sliding and A or B lines. For patients without lung sliding on lung examination, a clinical diagnosis of pneumothorax was considered. Gastric antrum assessment in the EASy examination is simplified to qualitatively assess for a grossly full stomach (Video 2).

Evaluation of Image Quality

All ultrasound images were saved and later reviewed by the supervising attending anesthesiologist proficient in POCUS to ensure proper image quality and consistency in phenotype classification. This post hoc review allowed for quality assurance to validate image adequacy and appropriateness of real-time decisions and to provide feedback to residents. Images were independently reviewed post hoc by a blinded POCUS expert (A.P.) to ensure consistency and to assess inter-rater reliability.

Subcostal cardiac image quality was evaluated based on a 12-point scoring system in which 0–2 points were assigned for each of the following six components of the examination: pericardium, RV size, RV function, interventricular septum, LV size, and LV function. Zero points were assigned if the evaluator was unable to assess the component. One point was given if the anatomy was not well visualized, additional views were required for evaluation, or if a pathology could otherwise not be ruled in or out. Two points were assigned if the anatomy was well visualized. The studies were graded as good (score 10–12), adequate (score 7–9), or poor (score 0–6) (11).

Image quality of the anterior lung and pleura was qualitative based on either the ability to view lung sliding and A or B lines, or the inability to obtain images. Gastric image quality was based on the ability to visualize the gastric antrum at the level of the descending aorta.

Data Collection and Outcomes of Interest

Patient demographics (height, weight, sex), Sequential Organ Failure Assessment score, indication for intubation (respiratory failure, neurologic impairment, cardiovascular instability, or emergent procedure), and assessment of hypotension following intubation were collected. Severe hypotension following intubation is defined as a mean arterial pressure of less than 55 mm Hg recorded within 15 minutes after the intubation procedure. The EASy-PDA Examination Report Sheet (Appendix 1, https://links.lww.com/CCX/B567) was used to document examination indication, image quality, hemodynamic phenotype identified, and clinical management and outcomes. The time required to complete EASy examination (time elapsed between first and last images) was also collected. Data for the report sheet were entered immediately post-intubation or during the initial stabilization phase.

RESULTS

EASy examinations were performed on 30 patients before EAM during the study period (Table 1). The mean time to complete the examination was 2.40 minutes (sd = 1.23 min), 1.89 minutes (sd = 0.76 min) for the faculty, and 3.17 minutes (sd = 1.40 min) for the residents. There were no significant discrepancies between the bedside phenotype classification, the post hoc supervisor classification, and the independent expert review, with a Cohen’s kappa of 0.9, indicating an almost perfect level of agreement among the evaluators.

TABLE 1.

Characteristics and Reasons for Intubation of the 30 Patients Who Received the Echocardiography Assessment Using Subcostal-Only-View Examination

Variable	n (%), n = 30
Age, median (IQR), yr	59.5 (52–77)
Men	18 (60)
Women	12 (40)
Weight, median (IQR), kg	76.5 (63.5–100.2)
Body mass index, median (IQR), kg/m2	27.6 (24–34.2)
Sequential Organ Failure Assessment score, median (IQR)a	5 (3–6)
Reason for intubation, n (%)
Respiratory failure	16 (53.3)
Neurologic impairment	9 (30.0)
Emergent procedure	3 (10.0)
Cardiovascular instability	2 (6.7)

IQR = interquartile range.

^aScores calculated using patients’ most recent values before intubation; if incomplete or unavailable, first values following intubation were used.

Image Quality

Of the SC4C images obtained, 11 were of good quality, 15 were of adequate quality, and three were of poor quality requiring a supporting parasternal long axis view. SC4C image could not be obtained in one patient due to severe abdominal pain. Of the IVC images obtained, 28 were of adequate quality. Two were unobtainable via the subxiphoid EASy examination and were obtained using a transhepatic anterior axillary approach. EASy examination alone without supporting views was successful in 26 of 30 patients. Anterior lung and pleural views were obtained in all 30 patients. Gastric antrum assessment was achieved in all 30 patients.

EASy Phenotypes

The EASy phenotypes identified, and the interventions performed before tracheal intubation (Fig. 5) are summarized in eTable 1 (https://links.lww.com/CCX/B567). Eighteen patients were characterized under cluster 1 (phenotypes 1, 2, and 3) with small or normal LV cavity size, and normal or increased LV myocardial contractility; 16 received a 10 mL/kg fluid bolus before tracheal intubation. One patient with phenotype 3 did not receive a fluid bolus due to the presence of pulmonary edema secondary to suspected diastolic dysfunction due to thickened LV, and one was already receiving fluids for hypotension before intubation request. Thirteen patients from cluster 1 received push doses of IV phenylephrine, while four received push doses of IV norepinephrine before induction of anesthesia for tracheal intubation; propofol was given for induction in all patients except one that received etomidate and another that received propofol with ketamine. Two patients were found to have a full gastric antrum on examination, and the decision was made to place a nasogastric tube for decompression before intubation.

Nine patients had severe systolic dysfunction and were characterized under cluster 2 (phenotype 4 and 5). Six of them received inotropic agents (norepinephrine or epinephrine) without a fluid bolus before induction of anesthesia; one received norepinephrine with a fluid bolus. Additionally, in all these patients, the decision was made to use etomidate or ketamine over propofol for induction of anesthesia.

Two patients were found to have severely enlarged RV with normal or increased LV contractility and were characterized under cluster 3 (phenotypes 6 and 7). Both received etomidate over propofol along with norepinephrine without a fluid bolus before induction of anesthesia. For one of these patients, a decision was made to try high-flow nasal oxygenation and avoid tracheal intubation until a workup for RV enlargement was completed, after which anesthesia returned to intubate the patient.

One patient was found to have a large pericardial effusion and was characterized under cluster 4 (phenotype 8). This patient had RV collapse during diastole and right atrium collapse during systole, thus contraindicating intubation. The patient was instead taken emergently to the operating room for a pericardial window.

DISCUSSION

We describe the successful integration of EASy-PDA as a part of bedside POCUS in the EAM of critically ill patients at a tertiary care academic medical center. We were able to train anesthesia residents to efficiently perform the examination and identify its phenotypes under supervision. We demonstrate changes in medical management based on bedside POCUS findings. Since tracheal intubation in critically ill patients is a high-risk procedure, routine use of POCUS before intubation may help optimize the patient’s cardiorespiratory status and tailor treatment.

Pre-intubation hypotension has been identified as a predictor for hemodynamic collapse in critically ill adults undergoing tracheal intubation (18). Preemptive fluid administration to improve hemodynamics has shown mixed results and the use of vasopressors as push-dose or infusions, although routinely used, is still being examined (19–23). Emerging evidence suggests that empiric vasopressors or fluid boluses for all patients before intubation is not associated with improved outcomes and can lead to harm when not tailored to the patient’s underlying physiology (20, 21). The identification of patients most likely to benefit from these interventions is important and can be guided by POCUS. Integration of POCUS with minimal delay informs targeted interventions based on real-time hemodynamic phenotyping.

For a majority of patients, POCUS influenced the choice and timing of vasopressor administration, fluid management, selection of induction agents, and decision to delay intubation. Critical examination findings—such as the presence of cardiac tamponade or a full gastric antrum—led to the appropriate management, sparing patients the risk of cardiopulmonary collapse or aspiration had they been intubated without timely assessment. Although thorough assessment of hemodynamic profiles is possible through other modalities and conventional POCUS, our EASy protocol offers an easy-to-learn, rapid diagnostic tool, which may broaden the accessibility of bedside POCUS without significant time and resource burden.

In our study, the EASy-PDA protocol was intentionally not applied to specific patient populations. This approach allowed us to assess the feasibility and clinical utility of the protocol across a diverse group of critically ill patients. For most patients in our study, POCUS examinations influenced management. We believe this structured, image-guided approach provides a meaningful improvement over empiric strategies by enabling patient-specific management.

Acute respiratory failure was the most common indication for tracheal intubation in our study. Depending on the presence and quality of pulmonary disease, parasternal and apical views may be difficult to obtain. Thus, the subxiphoid costal window used in the EASy examination may be the only option. The examination uses subcostal and subxiphoid windows to provide information regarding the pericardium, heart chambers, and IVC (10). The advantage of EASy over FTTE is the minimal training it requires, and time needed to perform the examination (11, 24). This study supports the routine integration of POCUS during EAM. The ability of our residents to rapidly deploy the EASy examination demonstrates that it can be an entry point to bedside echocardiography for novice users.

Our study is limited in generalizability given that it was a single-site study. Integration of POCUS into routine management of EAM needs further evaluation. Another limitation is the small number of patients included in the study and the retrospective nature of the study. The lack of a control group results in the inability to accurately assess the impact of POCUS on peri-intubation complications and patient outcomes. This limitation needs to be addressed in a multicenter, prospective study that explores differences in hemodynamic stability among patients receiving care based on EASy examination findings compared with patients receiving routine care. Barriers to implementation in larger cohorts exist and include training gaps, limited probe access, and cultural resistance within airway teams. We have demonstrated that the EASy examination takes minimal time to complete and requires minimal training, therefore, suggesting ease of implementation. The primary objective of this study was to assess the feasibility of POCUS deployment before EAM, which was achieved.

CONCLUSIONS

This study demonstrates that POCUS via our novel EASy-PDA protocol can be efficiently integrated into the performance of emergent tracheal intubation in critically ill patients with a PDA to assess hemodynamic stability. Using a limited number of high-yield views, the EASy-PDA examination can provide a quick and effective assessment to optimize hemodynamic management before EAM in critically ill patients. Further studies are needed to confirm and validate our findings in a larger and institutionally diverse patient cohort.