Bed-up-head-elevated Position versus Supine Sniffing Position in Patients Undergoing Rapid Sequence Intubation Using Direct Laryngoscopy in the Emergency Department – A Randomized Controlled Trial

Abstract

Introduction:

The objective of this study is to compare bed-up-head-elevated (BUHE) position with supine sniffing position (SSP) in patients undergoing rapid sequence intubation (RSI) using direct laryngoscopy in the emergency department (ED).

Methods:

This single-center randomized controlled superiority trial was carried out from September 2021 to December 2022 in an academic emergency medicine department. The patients undergoing RSI in ED were grouped into two arms, namely BUHE position and SSP. The primary outcome was the time taken for endotracheal intubation. The secondary outcomes were the first-pass success rates and postintubation complications.

Results:

A total of 136 patients were enrolled in the study. Time for intubation in the BUHE group was no different from SSP (32.09 s [interquartile range (IQR): 23.30–42.68] vs. 33.40 [IQR: 27.53–45.90], P = 0.17). There was a modest reduction in intubation time when performed by trained experts (22.5 s [IQR: 17.7–25.3] versus 30.3 s [IQR: 21.3–33.2], P = 0.04). The first-attempt success rate in the BUHE position was also similar to the SSP position ([91.18% vs. 90.91%] P = 0.958). Postintubation complications were lesser in BUHE compared to the SSP group ([7.4% vs. 19.7%] P = 0.04).

Conclusions:

In our study, BUHE position did not improve time to intubation and first-pass success rate in ED patients compared to SSP. A modest decrease in intubation time was noted while experts used the BUHE position. The postintubation complications were slightly lesser in the BUHE group.

INTRODUCTION

In the emergency department (ED), rapid sequence intubation (RSI) is a lifesaving and essential procedure performed on critically ill or injured patients who cannot maintain their airways or require mechanical ventilation.[1,2,3] RSI is an effective, controlled, and predictable airway management process in improving patient outcome.[4,5,6,7] However, emergency intubation is often performed under time pressure and in challenging clinical environments, which can increase the risk of adverse events. The potential complication includes hemodynamic instability, hypoxia, adverse drug reaction, delayed recognition of tube misplacement, and failed intubation.[8,9,10] The decision to perform intubation in the ED should be made carefully, weighing the potential benefits against the risks and the patient’s clinical status. To perform the procedure safely in such a scenario demands optimization of clinical circumstances such as patient conditions, devices, and human resources.[11,12,13]

The horizontal supine sniffing position (SSP) has traditionally been considered the optimal head position for direct laryngoscopy.[14] It is preferred with rationale that intubating person’s line of sight falls easily and comfortably on the glottic aperture.[15,16,17] In this position, the lower cervical spine is flexed, and the upper cervical spine is extended, with the patient supine on a flat bed with or without a pillow [Figure 1]. In 2007, Lee et al. introduced a novel bed-up-head-elevated (BUHE) technique during intubation associated with a superior laryngeal view.[16] Since then, multiple studies have shown the technique improved preoxygenation, decreased risk of aspiration, and improved laryngoscopic view.[17,18,19] In the BUHE position, the head of the bed is elevated to 25°–30° and a pillow is placed under the head so that the external auditory meatus is as high as the sternal notch. The neck is extended to make the face horizontal [Figure 2]. The impact of ramp angle and bed height on intubation outcome during simulated endotracheal intubation (ETI) was studied by Nikolla et al.[20] They proved a ramp angle of 45° with head end of the bed at the umbilical height of intubator was optimum with respect to the percentage of glottis opening. In a multicenter, randomized trial conducted in critically ill adults in the intensive care unit (ICU), the bed elevated position did not improve oxygenation during ETI. The position also increased the incidence of difficult intubation and decreased first-attempt intubation rate.[21]

Figure 1.

Supine sniffing position with head extended

Figure 2.

Bed-up-head-elevated position. Raise the back about 30°, then tilt the head section back to extend the neck

Till now, there is no predefined standard position for ETI in the ED, and most of the data regarding the positioning of the patient during intubation that we have today are extrapolated from the operating room and ICU which may not hold true for the patients coming to the ED. Henceforth, it is essential from the ED perspective to determine whether the appropriate position of the patient decreases the time for intubation and postintubation complications. To our knowledge, there are no randomized controlled trials (RCTs) on time taken for intubation during RSI in the bed-up-head elevation (BUHE) position in an academic ED.

We conducted the study to determine the effectiveness of BUHE position in time for successful intubation. We hypothesized that BUHE position is associated with improved glottic views that might decrease the intubation time and complication rates compared to SSP in emergency intubation. The primary outcome is to compare the time taken for ETI in a patient undergoing RSI using the direct laryngoscopy in BUHE versus SSP. The secondary outcomes included the first-pass success rate and postintubation complications.

METHODS

Study design and setting

We conducted the single-center RCT in the Department of Emergency Medicine and Trauma Care at JIPMER, a tertiary care hospital in Puducherry, South India, from September 2021 to December 2022. Being a tertiary care center, it caters to a large population and a referral unit for other peripheral centers. The department provides initial resuscitation and stabilization on an average of 60,000 cases annually. On average, 140 ETIs are done monthly in our resuscitation zone. The residents will manage the sickest patient rolled into the resuscitation zone under the guidance of consultants.

After a detailed review of the ethical aspects involved in the study, JIPMER Institute Ethics Committee approved the study protocol (JIP/IEC/2021/07) on July 10, 2021. The study is also registered under the Central Trials Registry-India (CTRI/2021/09/036576). All patient relatives gave informed oral consent before the intervention since there was no time to take written consent. Later, informed written consent was taken from the relative or the patient after stabilization.

Training environment

All intubations performed by residents in ED are supervised by board-certified emergency physicians. As an academic institute, residents perform intubation following department airway checklist. Majority of the intubations are performed using direct laryngoscope and video laryngoscopes are primarily opted in trauma patients. Bed elevated positions were previously used in suspected difficult intubation in obese patients. The proceduralist did not undergo a training for BUHE position before the study.

Participants

All patients undergoing RSI above 18 years of age in the ED were screened for the study. We excluded patients with trauma (suspected cervical and thoracolumbar vertebral fracture), airway obstruction secondary to advanced head-and-neck tumors or severe airway edema secondary to burns, injuries, and infections, contraindications to neck extension, history of the difficult airway from previous intubation history, crash intubation, and pregnant woman. The baseline characteristics included patient’s data on age, gender, weight, vital parameters on arrival, comorbidities, indication for intubation, induction, and paralytic agents used for intubation.

Randomization, intervention, and follow-up

Participants were randomized into arms in the ratio of 1:1 by block randomization. Randomization was done by random allocation using STATA 17 software with block sizes of 4. The allocation concealment in both arms was done by the sequentially numbered, opaque, sealed envelope technique. No blinding was done due to the nature of the study. All patients who presented to ED and required RSI were screened for the study. As the intubation done by experts and beginners differs, the emergency medicine residents and consultants who have performed at least 50 successful intubations were only included. Standard RSI technique was followed for all enrolled patients. The intubation was performed using direct laryngoscope with Macintosh blade. Both the groups in the preparation phase were assessed for any possible difficult airway and connected to a monitor for continuous recording of the heart rate, saturation, ECG, and blood pressure (BP). The identification of a difficult airway was performed by looking for external markers, assessing for upper airway obstructions, evaluating the ‘3-3-2 rule,’ and assessing neck mobility. The necessary equipment and drugs required for RSI were loaded and kept ready in the initial phase. The induction agents used were midazolam (0.1–0.3 mg/kg), ketamine (1–1.5 mg/kg), and propofol (1–1.5 mg/kg). The muscle relaxants employed were succinylcholine (1.5 mg/kg) and atracurium (0.3–0.5 mg/kg). Atracurium was preferred as a muscle relaxant when there is hyperkalemia and other contraindications to the use of succinylcholine. Then preoxygenation was done by administering 100% oxygen for 3 min or providing eight vital capacity breaths for both the groups.

Standard pretreatment agents used were based on the patient’s clinical scenario in both the groups of patients. Preoxygenation was performed using nonrebreather mask or bag-mask ventilation. This step was followed by giving a precalculated induction dose and paralytic agent simultaneously. The choice of the induction agent and paralytic agent used was decided by the emergency medicine resident or consultant, depending on the patient’s clinical scenario.

In the BUHE group, the head end of the bed is raised to an angle of 30° by flexion of bed at the hip level, which was measured and confirmed by a goniometer. Pillows or towels under the head were added or removed as needed to achieve the alignment of an imaginary line drawn through the external auditory meatus and sternal notch parallel to the ceiling. Once the desired position was completed, the total height of the bed was adjusted so that the top of the mattress at the head end of the bed was at the level of the umbilicus of the intubator [Figure 3].

Figure 3.

Resident performing intubation in bed-up-head-elevated position

In the SSP group, the patient is maintaining the supine position with flexion of the neck on the chest with a cushion under the occiput and extension (of 15°) of the head at the atlanto-occipital joint. This position was attained by adding or removing towels or pillows to achieve the alignment of the imaginary line drawn through the external auditory meatus and the sternal notch, and the patient’s face was parallel to the ceiling. Once the desired position is achieved, the total height of the bed is adjusted so that the top of the mattress at the head end of the bed is at the level of the umbilicus of the intubator. Based on expertise, we have classified residents with <3 years of experience as trainees and more than 3 years as trained experts (senior residents and consultants). After three intubation attempts in ETI, failed airway management protocol (American Society of Anesthesiologists difficult airway algorithm) would be done.

Outcome measurement

The time taken for ETI was measured in seconds, from when the tip of the laryngoscope blade passed through the incisor to the first detectable square wave end-tidal carbon dioxide level (ETCO₂) by the principal investigator. The waveform capnography was recorded in a spacelab health-care bedside monitor. The time taken for intubation was measured using stopwatch. During the procedure, the emergency medicine residents and consultants performing RSI recorded the Cormack–Lehane view. The first-pass success is defined as intubation with single laryngoscope insertion in the mouth. The principal investigator recorded data on baseline patient characteristics, pre- and postintubation vitals, complications, and management. All the patients were continuously monitored till 10 min postintubation, and vitals were recorded. The recorded ancillary maneuvers performed by assisting team members included backward, upward, rightward, and posterior pressure and external laryngeal manipulation. Postintubation complications were defined as peri-intubation hypoxia (saturation <90% or fall in >10%), airway trauma (bleeding from the oral cavity or loss of a tooth), bradycardia (heart rate <50 bpm), hypotension (systolic BP <90 mmHg or new or increased use of vasopressors), and cardiac arrest. The primary outcome is to compare the time taken for ETI in a patient using the direct laryngoscopy in BUHE versus SSP. The secondary outcomes included the first-pass success rate and postintubation complications.

Statistical analysis

The primary analysis was conducted on an intention-to-treat basis. On this basis, missed case sensitivity analysis is calculated by taking into account the best- and worst-case scenario. The sample size was calculated by assuming the minimal clinically significant difference in time to intubation between the two groups as 10s and pooled standard deviation of time to intubation derived from the previous study of 17s,[21] the sample size was estimated using a statistical formula for comparison of two independent means, calculated manually. A total of 122 patients (61 in each arm) with a 5% level of significance and 90% of power will be required. The initial estimate was 122. Considering a 10% loss per the previous studies,[22] the corrected sample size is 136. The distribution of categorical variables was expressed by frequency and percentages. The continuous variables were expressed by median with IQR. Comparison between the groups was done using an independent sample t-test or Mann–Whitney U test according to normality assumptions. All the statistical analysis will be carried out at a 5% significance level using statistical software SPSS 19 (United States), and P < 0.05 is considered significant.

RESULTS

Out of 1922 patients screened for eligibility during the study period, 136 patients were randomized for the study. Since being a high-volume ED with around 350 patients presenting per day, overcrowding is a major issue in patient randomization and inclusion in the study. Excluded patients were 420 patients with a history of trauma, 309 crash intubations since they presented in cardiac arrest, 27 patients with airway obstruction requiring intubation secondary to head-and-neck trauma, and 73 patients had a history of burns injuries and 76 with contraindication to neck extension. Being an academic ED, 236 patients were intubated by residents who performed <50 intubations in total. We could not recruit patients due to logistic issues like nonavailability of trolley beds (580) which could be height and angle adjustable and monitored beds with ETCO₂ (62). After recruitment and allocation, two patients had to be excluded from the study even before intervention. In the BUHE group, 68 patients and in the SSP group 66 patients received the intervention, and all were followed up till analysis [Figure 4]. Baseline characteristics are given in Table 1.

Figure 4.

Consolidated standards of reporting trial flow diagram

Table 1.

Baseline characteristics of patients stratified by study arm

Characteristics		BUHE (n=68), n (%)		SSP (n=66), n (%)		P
Age (year), mean±SD		51.83±12.58		49.91±13.87		0.62
Gender: Male, n (%)		45 (48.91)		47 (51.09)		0.53
Weight (kg), mean±SD		68.5±11.52		67.04±7.14		0.24
Vitals at presentation, mean±SD
Heart rate		97.7±15.3		93.8±17.9		0.43
Systolic blood pressure		121.3±21.8		122.8±21.4		0.81
Diastolic blood pressure		75.7±11.2		78.6±8.6		0.32
Respiratory rate		21.4±5.1		18.4±3.6		0.02
SpO2%		93.8±9.9		97.1±2.5		0.06
Comorbidities
Diabetic mellitus		17 (25)		18 (27.2)		0.84
Hypertension		26 (38.2)		20 (30.3)		0.36
CKD		7 (10.2)		4 (6.06)		0.53
Coronary artery disease		2 (2.9)		3 (4.5)		0.67
COPD		2 (2.9)		2 (3.03)		1.00
Malignancy		2 (2.9)		1 (1.51)		1.00
DCLD		2 (2.9)		3 (4.54)		0.67
CHF		1 (1.4)		2 (3.03)		0.61
Seizure		1 (1.4)		4 (6.06)		0.20
None		8 (11.7)		9 (13.6)		0.79
Diagnosis
Intracranial bleed/CVT/SAH		16 (23.53)		19 (28.79)		0.55
Acute respiratory distress syndrome		8 (11.76)		7 (10.61)		1.00
Poisoning		7 (10.29)		4 (6.06)		0.53
ICSOL		6 (8.82)		9 (13.64)		0.42
Status epilepticus		6 (8.82)		5 (7.58)		1.00
DKA		5 (7.35)		4 (6.06)		1.00
CHF		5 (7.35)		6 (9.09)		0.76
CKD		5 (7.35)		3 (4.55)		0.71
COPD		4 (5.88)		3 (4.55)		1.00
DCLD		3 (4.41)		4 (6.06)		0.71
Meningoencephalitis		2 (2.94)		1 (1.52)		1.00
Pancreatitis		1 (1.47)		1 (1.52)		1.00
Indication for intubation
AMS		34 (50)		43 (65.2)		0.08
Acidosis		12 (17.6)		11 (16.7)		1.00
Hypoxia		9 (13.2)		5 (7.6)		0.39
Seizure		7 (10.3)		6 (9.1)		1.00
Hypercarbia		5 (7.4)		1 (1.5)		0.20
Others		1 (1.5)		0 (0)		1.00
Induction agent
Midazolam		45 (66.18)		37 (56.06)		0.23
Ketamine		17 (25)		21 (31.82)		0.39
Propofol		6 (8.82)		8 (12.12)		0.54
Paralytic agent
Succinylcholine		65 (95.59)		61 (92.42)		0.48
Atracurium		3 (4.41)		5 (7.58)		0.48
Vecuronium		0		0

DCLD: Decompensated chronic liver disease, CHF: Congestive heart failure, CVT: Cerebral venous thrombosis, SAH: Subarachnoid hemorrhage, ICSOL: Intracranial space-occupying lesion, DKA: Diabetic ketoacidosis, CKD: Chronic kidney disease, COPD: Chronic obstructive pulmonary disease, AMS: Altered mental status, SD: Standard deviation, BUHE: Bed-up-head-elevated, SSP: Supine sniffing position

The median time for intubation in BUHE and in SSP was 32.09 s (IQR 23.30–42.68) vs. 33.40 s (IQR 27.53–45.90) respectively as per intention-to-treat analysis with best-case scenario in SSP considered. On similar analysis with worst-case scenario, values were 32.09 s (IQR: 23.30–42.68) and 34.33 s (IQR: 29.00–49.39), respectively. We performed intention-to-treat analysis considering the best- and worst-case scenario in the SSP group for dealing with the dropouts. The best- and worst-case scenario refers to minimum time and maximum taken for intubation in the SSP group. The median time for intubation in BUHE is 32.09 s (IQR: 23.30–42.68), and in SSP, it is 33.67 (IQR: 28.85–46.65) seconds as per protocol analysis. The first-pass success rate in BUHE is 91.18%, whereas in SSP, it is 90.91%. Successful intubation in the second attempt was in 5 patients each. Only one patient in SSP was intubated on the third attempt, and there was one failed airway incidence in the BUHE group. The total number of complications in the BUHE group was 5 (7.4%) and in the SSP group was 13 (19.7%), and the difference was statistically significant.

The median time to intubate based on operator expertise was calculated. In the BUHE group, trainees had a median time of 35.9 s compared to 22.5 s of trained experts. In the SSP group, trainees took a median time of 37.7 s whereas trained experts could perform in 30.3 s. A post hoc analysis was done to assess the improvement in saturation in both methods during preoxygenation. Preoxygenation improved oxygen saturation to more than 90% in among 17 of the 19 hypoxic patients. At the same time in the SSP group, only 13 out of 17 patients had SpO₂ improved to more than 90%. The ancillary maneurvers were performed lesser in BUHE group (11 patients) compared to the SSP group (18 patients). Ancillary equipment (bougie/alternate laryngoscopes) were used in 10 (14.7%) patients in BUHE and 6 (9.09%) patients in SSP. The primary and secondary outcomes are given in Table 2.

Table 2.

Primary and secondary outcome results

Outcomes		BUHE (n=68), n (%)		SSP (n=66), n (%)		P
Time to intubate (s)#, median (IQR)		32.09 (23.30–42.68)		33.40* (27.53–45.90)		0.17
Time to intubate (s)$, median (IQR)		32.09 (23.30–42.68)		34.33 (29–49.33)		0.05
Time to intubate (s), median (IQR)		32.09 (23.30–42.68)		33.67 (28.35–46.65)		0.09
First-pass success rate		62 (91.18)		60 (90.91)		0.95
Postintubation complications
Total		5 (7.4)		13 (19.7)		0.04
Hypoxia		1 (1.48)		2 (3.03)		0.61
Hypotension		3 (4.42)		7 (10.6)		0.20
Bradycardia		1 (1.48)		2 (3.03)		0.61
Airway trauma		0		1 (1.52)		0.30
Cardiac arrest		0		1 (1.52)		0.35
Time to intubate (s)
Trainees (n=110)		35.9 (27.29–56.25)		37.71 (30.75–51.75)		0.21
Trained experts’ number (n=24)		11		13
Trained experts (n=24)		22.5 (17.7–25.3)		30.3 (21.36–33.25)		0.04
Ancillary maneuver (BURP + ELM)		11 (16.7)		18 (27.27)		0.11
Ancillary equipment (Bougie/alternate laryngoscope)		10 (14.7)		6 (9.09)		0.31
Cormack–Lehane grading
1		53 (77.94)		48 (72.73)
2		12 (17.65)		13 (19.70)
3		3 (4.41)		4 (6.06)
4		0		1 (1.52)

*The results of time to intubate as per intention-to-treat analysis (best case scenario in SSP considered). Here the total sample size in the SSP group is 68, ^#Intention-to-treat analysis considering best case scenario of SSP, ^$Intention-to-treat analysis considering worst-case scenario of SSP. BUHE: Bed-up-head-elevated, SSP: Supine sniffing position, IQR: Interquartile range, BURP: Backward, upward, rightward, and posterior pressure, ELM: External laryngeal manipulation

DISCUSSION

We found the intubation time in the BUHE group comparable to the SSP group. Considering the worst-case scenario in the SSP group for intention-to-treat analysis also yielded a similar result. A difference of around 2 s between the two groups cannot be of a clinical significance. Time to intubation has been defined in multiple ways in various studies, and comparing it is difficult across studies. Our results were almost identical to the study conducted in operating room where they compared the time taken for intubation when done by trainees between the backup and the supine positions as 24 and 28 s, respectively.[22] We analyzed the level of expertise that would have affected the ease of laryngoscopy in our study. Trainees performed majority of the intubations with a difference in a median time of about 1.8 s. The difference between the two arms is more when intubation is performed by expert trainers (22.5 s vs. 30.3 s). However, for a method where the results are already skewed toward the left, even a difference of around 8 s from the total time of 32–33 s could be clinically significant, especially for patients who are critically ill and have a low functional residual capacity or are borderline hypoxic on presentation. The study done in operating room also noted a larger difference when performed by a senior anesthetist.[22] We found that experts had a significant difference of 13.4s compared to trainees in the BUHE group. This accounts for a 68% reduction in intubation time taking a median time of 32–34 s. The difference based on expertise is only 7.4s in the SSP group. When the provider’s experience level increased, BUHE might be a better method for RSI and could be chosen as the standard position for intubation. On another note, intubators’ experience would have affected the ease of laryngoscopy in the BUHE group. This could be the reason for not attaining a statistically significant difference since majority of intubations were done by junior residents with only 2 years of experience. In several other studies, intubations were done by only one or two physicians.[23,24,25,26]

In the present study, the first-pass success rate was more than 90%, much greater than the reported rate of 78.3%–85% in other studies.[24,25,26] The better laryngeal exposure in the BUHE position could be attributed as one reason. Head-end elevation has been suggested to reduce the directional force along the laryngoscope handle and also improve the line of sight.[27,28] Head elevation and neck flexion improved the full laryngeal exposure with less force.[27] Our study’s improved first-pass success rate could also be due to the practice of using stylet-assisted intubations. The ancillary equipment used in the present study were bougie and video laryngoscope in the present study, and fewer ancillary maneuvers were performed in BUHE when compared to the SSP. In a study conducted by Lee et al., the ancillary maneuvers used were lesser in the ramped-up position (7%) when compared to the sniffing position (42%).[29]

In a high-volume center like our ED, the trauma constitutes a larger proportion of intubation. We excluded 24% of the initial screened as applying the bed elevated position in trauma patients could not be assessed in our study. The suspected injury to the cervical and thoracolumbar spine is deemed unsafe to have BUHE position. In a busy and overcrowded ED, there were numerous logistic issues during study conduction. We could perform the randomization only upon availability of the appropriate beds, monitors with ETCO₂, and availability of residents with required intubations.

The incidence of complications during intubation may vary depending on patient factors, provider experience, and specific clinical situations. The BUHE group had fewer complications than the SSP group in our study. A similar reduced odds of airway complication was seen in emergency intubation performed by an anesthesiologist. The improved safety was also noted in low-risk critically ill adults.[7] We found that not only the incidence of hypoxia was lower in BUHE but also a better improvement in saturation after preoxygenation. This could be explained by improved ventilation-perfusion matching and functional residual capacity when head-elevated positioning is done. On supine position, it is more difficult to take full breaths and the posterior lung becomes prone to atelectatic collapse which reduces oxygen reservoir with reduced safe apnea time.[30] Our study also showed a lower incidence of hypotension when BUHE is employed (4.4% vs. 10.6%). However, this complication was not adjusted for the indication of intubation, proceduralist, and RSI medication. The head-elevated position is thought to potentially cause hypotension, as it may lead to blood pooling in the lower extremities and consequently reduce cardiac output. This concern is heightened during RSI, where the vasodilatory effects of induction agents could exacerbate these effects. The meta-analysis published by Tsan et al. which included 7 studies with 1917 patients reported no complications related to the ramping or sniffing position. There was also no report of occurrences of hypotension in the ramping group.[24] However, it is important to note that this area remains insufficiently explored, as most human studies including our study lack the statistical power to detect a difference. In our study, the choice of induction drugs, premedication agents such as fluids and push-dose pressors were based on patient’s clinical scenario and physician’s choice. We did not record the specific amount of fluid boluses and push-dose pressors in each group, and it is possible that physicians could have administered this anticipating hypotension in BUHE or based on the induction agents used. There was only one cardiac arrest noted in the SSP group. BUHE patient positioning is an easy maneuver to perform by hospital staff and requires no advanced technology and power source other than height-adjustable beds. Studies also mention BUHE as a suitable position optimizing a variety of airway management techniques, including ventilation by facemask, extraglottic airways, and video laryngoscopy.[7]

Limitation

It is a single-center study excluding multiple patients presenting to ED. One inevitable weakness was unblinded intubating physicians to the patient’s position and method of the study. This could have contributed to observer bias in the study. Since the intubating physicians knew that they were observed during the procedure, the Hawthorne effect cannot be ruled out. The investigator recording the outcome was also unblended. We enrolled only 7% of the patients screened. In retrospection, we can improve the RCT by solving the logistic issues like nonavailability of height adjustable beds in trial conduction. Most of the intubations were done by emergency medicine residents, and their level of experience and competence with prior intubations was not recorded. It could have led to interobserver variability and confounders.

CONCLUSIONS

In summary, we found that there was no decrease in time for intubation and first-pass success rate in the BUHE group compared to the SSP group. However, with higher expertise, there is a modest reduction in intubation time between both arms. Higher postintubation complications in the SSP group with apparent difference from BUHE were seen. Further multicenter academic ED-based RCTs are warranted to suggest BUHE as a standard position for RSI.

Research quality and ethics statement

The research was conducted after approval from IEC (IEC 2021/07). The study is registered with the CTRI-CTRI/2021/09/036576. The authors followed applicable EQUATOR Network (http://www.equator-network.org) guidelines for reporting the study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.