The Lung Cancer Prediction Model "Stress Test": Assessment of Models' Performance in a High-Risk Prospective Pulmonary Nodule Cohort

BACKGROUND

Pulmonary nodules represent a growing health care burden because of delayed diagnosis of malignant lesions and overtesting for benign processes. Clinical prediction models were developed to inform physician assessment of pretest probability of nodule malignancy but have not been validated in a high-risk cohort of nodules for which biopsy was ultimately performed.

RESEARCH QUESTION

Do guideline-recommended prediction models sufficiently discriminate between benign and malignant nodules when applied to cases referred for biopsy by navigational bronchoscopy?

STUDY DESIGN AND METHODS

We assembled a prospective cohort of 322 indeterminate pulmonary nodules in 282 patients referred to a tertiary medical center for diagnostic navigational bronchoscopy between 2017 and 2019. We calculated the probability of malignancy for each nodule using the Brock model, Mayo Clinic model, and Veterans Affairs (VA) model. On a subset of 168 patients who also had PET-CT scans before biopsy, we also calculated the probability of malignancy using the Herder model. The performance of the models was evaluated by calculating the area under the receiver operating characteristic curves (AUCs) for each model.

RESULTS

The study cohort contained 185 malignant and 137 benign nodules (57% prevalence of malignancy). The malignant and benign cohorts were similar in terms of size, with a median longest diameter for benign and malignant nodules of 15 and 16 mm, respectively. The Brock model, Mayo Clinic model, and VA model showed similar performance in the entire cohort (Brock AUC, 0.70; 95% CI, 0.64-0.76; Mayo Clinic AUC, 0.70; 95% CI, 0.64-0.76; VA AUC, 0.67; 95% CI, 0.62-0.74). For 168 nodules with available PET-CT scans, the Herder model had an AUC of 0.77 (95% CI, 0.68-0.85).

INTERPRETATION

Currently available clinical models provide insufficient discrimination between benign and malignant nodules in the common clinical scenario in which a patient is being referred for biopsy, especially when PET-CT scan information is not available.

Robotic versus Electromagnetic bronchoscopy for pulmonary LesIon AssessmeNT: the RELIANT pragmatic randomized trial

BACKGROUND

Robotic-assisted bronchoscopy has recently emerged as an alternative to electromagnetic navigational bronchoscopy for the evaluation of peripheral pulmonary lesions. While robotic-assisted bronchoscopy is proposed to have several advantages, such as an easier learning curve, it is unclear if it has comparable diagnostic utility as electromagnetic navigational bronchoscopy.

METHODS

Robotic versus Electromagnetic bronchoscopy for pulmonary LesIon AssessmeNT (RELIANT) is an investigator-initiated, single-center, open label, noninferiority, cluster randomized controlled trial conducted in two operating rooms at Vanderbilt University Medical Center. Each operating room (OR) is assigned to either robotic-assisted or electromagnetic navigational bronchoscopy each morning, with each OR day considered one cluster. All patients undergoing diagnostic bronchoscopy for evaluation of a peripheral pulmonary lesion in one of the two operating rooms are eligible. Schedulers, patients, and proceduralists are blinded to daily group allocations until randomization is revealed for each operating room each morning. The primary endpoint is the diagnostic yield defined as the proportion of cases yielding lesional tissue. Secondary and safety endpoints include procedure duration and procedural complications. Enrolment began on March 6, 2023, and will continue until 202 clusters have been accrued, with expected enrolment of approximately 400 patients by the time of completion in March of 2024.

DISCUSSION

RELIANT is a pragmatic randomized controlled trial that will compare the diagnostic yield of the two most commonly used bronchoscopic approaches for sampling peripheral pulmonary lesions. This will be the first known cluster randomized pragmatic trial in the interventional pulmonology field and the first randomized controlled trial of robotic-assisted bronchoscopy.

TRIAL REGISTRATION

ClinicalTrials.gov registration (NCT05705544) on January 30, 2023.

Spray Cryotherapy for Benign Large Airway Stenosis: A Multicenter Retrospective Cohort Study of Safety and Practice Patterns

BACKGROUND

Benign airway stenosis (BAS) represents a significant burden on patients, providers, and healthcare systems. Spray cryotherapy (SCT) has been proposed as an adjunctive treatment to reduce BAS recurrence. We sought to examine safety and practice variations of the latest SCT system when used for BAS.

METHODS

We conducted a retrospective multicenter cohort study in seven academic institutions within the Interventional Pulmonary Outcomes Group. All patients who underwent at least one SCT session with a diagnosis of BAS at the time of procedure at these institutions were included. Demographics, procedure characteristics, and adverse events were captured through each center's procedural database and electronic health record.

RESULTS

A total of 102 patients underwent 165 procedures involving SCT from 2013 to 2022. The most frequent etiology of BAS was iatrogenic (n = 36, 35%). In most cases, SCT was used prior to other standard BAS interventions (n = 125; 75%). The most frequent SCT actuation time per cycle was five seconds. Pneumothorax complicated four procedures, requiring tube thoracostomy in two. Significant post-SCT hypoxemia was noted in one case, with recovery by case conclusion and no long-term effects. There were no instances of air embolism, hemodynamic compromise, or procedural or in-hospital mortality.

CONCLUSION

SCT as an adjunctive treatment for BAS was associated with a low rate of complications in this retrospective multicenter cohort study. SCT-related procedural aspects varied widely in examined cases, including actuation duration, number of actuations, and timing of actuations relative to other interventions.

Diagnostic Yield vs Diagnostic Accuracy for Peripheral Lung Biopsy Evaluation: Evidence Supporting a Future Pragmatic End Point

BACKGROUND

Diagnostic yield and accuracy endpoints have been used inconsistently in the evaluation of advanced diagnostic bronchoscopy devices and techniques, limiting between-study comparisons. In addition, diagnostic accuracy can be adjudicated only after prolonged clinical follow-up, which delays reporting on the performance of novel devices.

RESEARCH QUESTION

Will a conservative diagnostic yield definition result in few false-negative initial results to closely approximate diagnostic accuracy and represent a useful outcome for future studies of diagnostic utility?

METHODS

Commonly used definitions of diagnostic yield were applied to a prospective data set of consecutive peripheral pulmonary lesions sampled by navigational bronchoscopy from 2017 to 2019. All consider malignancy to be diagnostic but differ in their classification of nonmalignant biopsy findings, which were subcategorized as specific benign, nonspecific benign, or normal lung. Diagnostic yield calculations were also compared with diagnostic accuracy, defined as the proportion of biopsy specimens deemed diagnostic by each definition that were confirmed accurate through 2 years of follow-up.

RESULTS

A total of 450 biopsy specimens of lesions were analyzed. The prevalence of malignancy was 60.9% (274 of 450). On initial bronchoscopy pathology, there were 227 malignant diagnoses (50.4%), with a single false positive (0.4%). Among 104 biopsy specimens with specific benign findings, only two were false negative for malignancy (1.9%). There were 119 nonspecific benign biopsy specimens, with 46 false negatives for malignancy (38.7%). The discrepancy between diagnostic yield and accuracy was 0.7% for the conservative definition, which only considered malignant or specific benign findings as diagnostic.

INTERPRETATION

A conservative diagnostic yield definition excluding nonspecific benign diagnoses closely approximated diagnostic accuracy through 2 years' follow-up, with a less than 1% discrepancy. Using this conservative yield definition may allow for dissemination of reliable diagnostic utility data without protracted delays needed for follow-up data in this era of rapid technological change in advanced diagnostic bronchoscopy.

Navigational Bronchoscopy versus Computed Tomography-guided Transthoracic Needle Biopsy for the Diagnosis of Indeterminate Lung Nodules: protocol and rationale for the VERITAS multicenter randomized trial

Background

Lung nodule incidence is increasing. Many nodules require biopsy to discriminate between benign and malignant etiologies. The gold-standard for minimally invasive biopsy, computed tomography-guided transthoracic needle biopsy (CT-TTNB), has never been directly compared to navigational bronchoscopy, a modality which has recently seen rapid technological innovation and is associated with improving diagnostic yield and lower complication rate. Current estimates of the diagnostic utility of both modalities are based largely on non-comparative data with significant risk for selection, referral, and publication biases.

Methods

The VERITAS trial (na V igation E ndoscopy to R each Indeterminate lung nodules versus T ransthoracic needle A spiration, a randomized controlled S tudy) is a multicenter, 1:1 randomized, parallel-group trial designed to ascertain whether electromagnetic navigational bronchoscopy with integrated digital tomosynthesis is noninferior to CT-TTNB for the diagnosis of peripheral lung nodules 10-30 mm in diameter with pre-test probability of malignancy of at least 10%. The primary endpoint is diagnostic accuracy through 12 months follow-up. Secondary endpoints include diagnostic yield, complication rate, procedure duration, need for additional invasive diagnostic procedures, and radiation exposure.

Discussion

The results of this rigorously designed trial will provide high-quality data regarding the management of lung nodules, a common clinical entity which often represents the earliest and most treatable stage of lung cancer. Several design challenges are described. Notably, all nodules are centrally reviewed by an independent interventional pulmonology and radiology adjudication panel relying on pre-specified exclusions to ensure enrolled nodules are amenable to sampling by both modalities while simultaneously protecting against selection bias favoring either modality. Conservative diagnostic yield and accuracy definitions with pre-specified criteria for what non-malignant findings may be considered diagnostic were chosen to avoid inflation of estimates of diagnostic utility.

Trial registration

ClinicalTrials.gov NCT04250194.

Inter-rater reliability of a novel objective endpoint for benign central airway stenosis interventions: Segmentation-based volume rendering of computed tomography scans

OBJECTIVES

To evaluate the reliability of a novel segmentation-based volume rendering approach for quantification of benign central airway obstruction (BCAO).

DESIGN

A retrospective single-center cohort study.

SETTING

Data were ascertained using electronic health records at a tertiary academic medical center in the United States.

PARTICIPANTS AND INCLUSION

Patients with airway stenosis located within the trachea on two-dimensional (2D) computed tomography (CT) imaging and documentation of suspected benign etiology were included. Four readers with varying expertise in quantifying tracheal stenosis severity were selected to manually segment each CT using a volume rendering approach with the available free tools in the medical imaging viewing software OsiriX (Bernex, Switzerland). Three expert thoracic radiologists were recruited to quantify the same CTs using traditional subjective methods on a continuous and categorical scale.

OUTCOME MEASURES

The interrater reliability for continuous variables was calculated by the intraclass correlation coefficient (ICC) using a two-way mixed model with 95% confidence intervals (CI).

RESULTS

Thirty-eight patients met the inclusion criteria, and fifty CT scans were selected for measurement. The most common etiology of BCAO was iatrogenic in 22 patients (58%). There was an even distribution of chest and neck CT imaging within our cohort. The average ICC across all four readers for the volume rendering approach was 0.88 (95% CI, 0.84 to 0.93), suggesting good to excellent agreement. The average ICC for thoracic radiologists for subjective methods on the continuous scale was 0.38 (95% CI, 0.20 to 0.55), suggesting poor to fair agreement. The kappa for the categorical approach was 0.26, suggesting a slight to fair agreement amongst the raters.

CONCLUSION

In this retrospective cohort study, agreement was good to excellent for raters with varying expertise in airway cross-sectional imaging using a novel segmentation-based volume rendering approach to quantify BCAO. This proposed measurement outperformed our expert thoracic radiologists using conventional subjective grading methods.

Safety and utility of indwelling pleural catheters in lung transplant recipients

INTRODUCTION

The safety and efficacy of indwelling pleural catheters (IPCs) in lung allograft recipients is under-reported.

METHODS

We performed a multicenter, retrospective analysis between 1/1/2010 and 6/1/2022 of consecutive IPCs placed in lung transplant recipients. Outcomes included incidence of infectious and non-infectious complications and rate of auto-pleurodesis.

RESULTS

Seventy-one IPCs placed in 61 lung transplant patients at eight centers were included. The most common indication for IPC placement was recurrent post-operative effusion. IPCs were placed at a median of 59 days (IQR 40-203) post-transplant and remained for 43 days (IQR 25-88). There was a total of eight (11%) complications. Infection occurred in five patients (7%); four had empyema and one had a catheter tract infection. IPCs did not cause death or critical illness in our cohort. Auto-pleurodesis leading to the removal of the IPC occurred in 63 (89%) instances. None of the patients in this cohort required subsequent surgical decortication.

CONCLUSIONS

The use of IPCs in lung transplant patients was associated with an infectious complication rate comparable to other populations previously studied. A high rate of auto-pleurodesis was observed. This work suggests that IPCs may be considered for the management of recurrent pleural effusions in lung allograft recipients.

Robotic versus Electromagnetic Bronchoscopy for Pulmonary LesIon AssessmeNT: the RELIANT pragmatic randomized trial

Background

Robotic assisted bronchoscopy has recently emerged as an alternative to electromagnetic navigational bronchoscopy for the evaluation of peripheral pulmonary lesions. While robotic assisted bronchoscopy is proposed to have several advantages, such as an easier learning curve, it is unclear if it has comparable diagnostic utility as electromagnetic navigational bronchoscopy.

Methods

Robotic versus Electromagnetic Bronchoscopy for Pulmonary LesIon AssessmeNT (RELIANT) is an investigator-initiated, single-center, open label, noninferiority, cluster randomized controlled trial conducted in two operating rooms at Vanderbilt University Medical Center. Each operating room is assigned to either robotic assisted or electromagnetic navigational bronchoscopy each morning, with each OR day considered one cluster. All patients undergoing diagnostic bronchoscopy for evaluation of a peripheral pulmonary lesion in one of the two operating rooms are eligible. Schedulers, patients and proceduralists are blinded to daily group allocations until randomization is revealed for each operating room each morning. The primary endpoint is the diagnostic yield defined as the proportion of cases yielding lesional tissue. Secondary and safety endpoints include procedure duration and procedural complications. Enrolment began on March 6, 2023, and will continue until 202 clusters have been accrued, with expected enrolment of approximately 400 patients by the time of completion in March of 2024.

Discussion

RELIANT is a pragmatic randomized controlled trial that will compare the diagnostic yield of the two most commonly used bronchoscopic approaches for sampling peripheral pulmonary lesions. This will be the first known cluster randomized pragmatic trial in the interventional pulmonology field and the first randomized controlled trial of robotic assisted bronchoscopy.

Trial registration

ClinicalTrials.gov registration (NCT05705544) on January 30, 2023.

Comparative Treatment Outcomes for Idiopathic Subglottic Stenosis: 5-Year Update

The North American Airway Collaborative (NoAAC) previously published a 3-year multi-institutional prospective cohort study showing variation in treatment effectiveness between 3 primary surgical techniques for idiopathic subglottic stenosis (iSGS). In this report, we update these findings to include 5 years of data evaluating treatment effectiveness. Patients in the NoAAC cohort were re-enrolled for 2 additional years and followed using the prespecified published protocol. Consistent with prior data, prospective observation of 487 iSGS patients for 5 years showed treatment effectiveness differed by modality. Cricotracheal resection maintained the lowest rate of recurrent operation (5%), followed by endoscopic resection with adjuvant medical therapy (30%) and endoscopic dilation (50%). These data support the initial observations and continue to provide value to providers and patients navigating longitudinal decision-making. Level of evidence: 2-prospective cohort study.

Shape-Sensing Robotic-Assisted Bronchoscopy vs Digital Tomosynthesis-Corrected Electromagnetic Navigation Bronchoscopy: A Comparative Cohort Study of Diagnostic Performance

BACKGROUND

Electromagnetic navigational bronchoscopy has been the dominant bronchoscopic technology for targeting small peripheral lesions and now includes digital tomosynthesis-electromagnetic navigational bronchoscopy (DT-ENB), allowing near-real-time intraprocedural nodule visualization. Shape-sensing robotic-assisted bronchoscopy (ssRAB), with improved catheter stability and articulation recently became available. Although the diagnostic performance of these two methods seems higher than that of legacy systems, data remain limited. We sought to compare the diagnostic yield of these two novel platforms after their introduction at our institution.

RESEARCH QUESTION

Does the diagnostic yield of ssRAB differ significantly from that of DT-ENB in patients undergoing biopsy of peripheral pulmonary lesions (PPLs)?

STUDY DESIGN AND METHODS

This retrospective comparative cohort study analyzed prospectively collected data on consecutive procedures performed with DT-ENB and ssRAB in their first 6 months of use at our institution. Biopsies were considered diagnostic if histopathologic analysis revealed malignancy or specific benign features that readily explained the presence of a PPL. Nonspecific inflammation, normal lung or airway, and atypia not diagnostic of malignancy were considered nondiagnostic.

RESULTS

SSRAB was used to biopsy 143 PPLs in 133 patients and DT-ENB was used to biopsy 197 PPLs in 170 patients. Diagnostic yield was 77% for ssRAB (110 of 143 PPLs) and 80% (158 of 197 PPLs) for DT-ENB (OR, 0.8; 95% CI, 0.5-1.4; P = .4). Median lesion diameters were 17 and 19 mm, respectively. No difference in diagnostic yield was found after adjustment for lesion size, bronchus sign, peripheral vs middle third location, and sex. Pneumothorax complicated 1.5% of ssRAB and 1.8% of DT-ENB procedures (P = .86).

INTERPRETATION

SSRAB and DT-ENB showed comparable diagnostic yields and safety profiles in this comparative cohort study.

Safety and Feasibility of a Sheath Cryoprobe for Bronchoscopic Transbronchial Biopsy: The FROSTBITE Trial

BACKGROUND

Bronchoscopic lung biopsy is typically performed using transbronchial forceps. However, this method is limited by small sample size and presence of crush artifact. Cryobiopsy offers the potential to overcome these limitations with larger artifact-free samples but has not been widely adopted due to concerns over increased rates of bleeding and pneumothorax. A new, smaller 1.1-mm cryoprobe has been developed that operates in a similar fashion to forceps, though the safety profile of this cryoprobe has not yet been prospectively studied.

OBJECTIVE

The aim of this study was to investigate the safety of transbronchial biopsy using a novel 1.1-mm cryoprobe.

METHODS

This prospective, single-arm study enrolled patients referred for transbronchial biopsy. All procedures were performed using the 1.1-mm cryoprobe with oversheath. The primary outcome was the composite of significant complications related to the cryobiopsy procedure (bleeding Grade ≥3, pneumothorax Grade ≥2, and respiratory failure). Bleeding and pneumothorax were graded according to previously published scales.

RESULTS

Fifty participants from two academic medical centers underwent transbronchial cryobiopsy. Indications for biopsy included evaluation of lung transplant allograft (50%), diffuse lung disease (44%), and pulmonary parenchymal lesion (6%). There were two pneumothoraces (4%), neither of which required aspiration or chest tube placement. There were no Grade 3 or 4 bleeding events. Mild bleeding (Grade ≤2) was observed in 25 cases (50%). No complications occurred that met the a priori primary outcome of bleeding Grade ≥3, pneumothorax Grade ≥2, and respiratory failure.

CONCLUSIONS

Transbronchial cryobiopsy using a 1.1-mm cryoprobe is feasible with an acceptable safety profile.

Association between terminal pleural elastance and radiographic lung re-expansion after therapeutic thoracentesis in patients with symptomatic pleural effusion: a post-hoc analysis of a randomised trial

OBJECTIVES

Recurrent symptomatic effusions can be durably managed with pleurodesis or placement of indwelling pleural catheters. Recent pleurodesis trials have largely relied on lung re-expansion on post-thoracentesis radiograph as an inclusion criterion rather than pleural elastance as determined by manometry, which is an important predictor of successful pleurodesis. We investigated the association between lung re-expansion on post-pleural drainage chest imaging and pleural physiology, with particular attention to pleural elastance over the final 200 mL aspirated.

DESIGN

Post-hoc analysis of a recent randomised trial.

SETTING AND PARTICIPANTS

Post-results analysis of 61 subjects at least 18 years old with symptomatic pleural effusions estimated to be at least of 0.5 L in volume allocated to manometry-guided therapeutic thoracentesis in a recent randomised trial conducted at two major university hospitals in the USA.

PRIMARY OUTCOME MEASURES

The primary outcome was concordance of radiographic with normal terminal pleural elastance over the final 200 mL aspirated. We label this terminal elastance 'visceral pleural recoil', or the tendency of the maximally expanded lung to withdraw from the chest wall.

RESULTS

Post-thoracentesis chest radiograph and thoracic ultrasound indicated successful lung re-expansion in 69% and 56% of cases, respectively. Despite successful radiographic lung re-expansion, visceral pleural recoil was abnormal in 71% of subjects expandable by radiograph and 77% expandable by ultrasound. The sensitivity and positive predictive value of radiographic lung re-expansion for normal visceral pleural recoil were 44% and 24%, respectively.

CONCLUSION

Radiographic lung re-expansion by post-thoracentesis chest radiograph or thoracic ultrasound is a poor surrogate for normal terminal pleural elastance. Clinical management of patients with recurrent symptomatic pleural effusions guided by manometry rather than post-thoracentesis imaging might produce better outcomes, which should be investigated by future clinical trials.

TRIAL REGISTRATION NUMBER

NCT02677883; Post-results.

Bronchoscopy in Patients With Known or Suspected COVID-19: Results From the Global Pandemic SARS-CoV-2 Bronchoscopy Database (GPS-BD)

BACKGROUND

Amid the Coronavirus Disease 2019 (COVID-19) pandemic, the benefits and risks of bronchoscopy remain uncertain. This study was designed to characterize bronchoscopy-related practice patterns, diagnostic yields, and adverse events involving patients with known or suspected COVID-19.

METHODS

An online survey tool retrospectively queried bronchoscopists about their experiences with patients with known or suspected COVID-19 between March 20 and August 20, 2020. Collected data comprised the Global Pandemic SARS-CoV-2 Bronchoscopy Database (GPS-BD). All bronchoscopists and patients were anonymous with no direct investigator-to-respondent contact.

RESULTS

Bronchoscopy procedures involving 289 patients from 26 countries were analyzed. One-half of patients had known COVID-19. Most (82%) had at least 1 pre-existing comorbidity, 80% had at least 1 organ failure, 51% were critically ill, and 37% were intubated at the time of the procedure. Bronchoscopy was performed with diagnostic intent in 166 (57%) patients, yielding a diagnosis in 86 (52%). and management changes in 80 (48%). Bronchoscopy was performed with therapeutic intent in 71 (25%) patients, mostly for secretion clearance (87%). Complications attributed to bronchoscopy or significant clinical decline within 12 hours of the procedure occurred in 24 (8%) cases, with 1 death.

CONCLUSION

Results from this international database provide a widely generalizable characterization of the benefits and risks of bronchoscopy in patients with known or suspected COVID-19. Bronchoscopy in this setting has reasonable clinical benefit, with diagnosis and/or management change resulting from about half of the diagnostic cases. However, it is not without risk, especially in patients with limited physiological reserve.

Diagnostic Yield of Digital Tomosynthesis-assisted Navigational Bronchoscopy for Indeterminate Lung Nodules

BACKGROUND

Navigational bronchoscopy is commonly used to sample lung nodules, with a better safety profile but lower diagnostic yield than computerized tomography-guided transthoracic needle biopsy. The addition of digital tomosynthesis to electromagnetic navigation, using intraprocedural images obtained from a C-arm fluoroscope to identify target lesion location and update navigational guidance, may improve diagnostic yield.

METHODS

Consecutive bronchoscopies using tomosynthesis-assisted fluoroscopic electromagnetic navigational bronchoscopy (F-ENB) at a single institution over a 1-year period were included. The primary outcome was diagnostic yield. A bronchoscopy was defined as diagnostic if pathologic examination revealed malignancy or specific histological findings indicative of lesional sampling with confirmatory 6-month follow-up for benign lesions.

RESULTS

A total of 324 patients with 363 nodules underwent F-ENB between April 25, 2018 and April 29, 2019. The average nodule size was 1.9±1.1 cm, 65% of the nodules were located in the peripheral third of the lung. A bronchus sign was present in 24% of cases. Of the 363 nodules, 299 (82.4%) had lesional findings. At 6-month follow-up, among these 299 nodules, 6 were found to be false negatives and 12 nodules were lost to follow-up. Considering all nodules lost to follow-up as false negatives, the 6-month diagnostic yield was 77.4%. Pneumothorax complicated 8 (2.5%) of cases. There was 1 episode of respiratory failure.

CONCLUSION

This retrospective study suggests the diagnostic yield of F-ENB may exceed that of traditional ENB. Future prospective and comparative studies are needed to confirm these promising data.

Sight Unseen: Diagnostic Yield and Safety Outcomes of a Novel Multimodality Navigation Bronchoscopy Platform with Real-Time Target Acquisition

BACKGROUND

Several advanced bronchoscopy platforms are currently available, but the clinical data supporting their use vary. Electromagnetic navigation bronchoscopy (ENB) remains the dominant technology; it is limited by its reliance on preoperative computed tomography, which only approximates patient anatomy during the procedure. Recently, ENB was enhanced with the (1) addition of digital tomosynthesis-based navigation correction, (2) improvements in planning algorithms, and (3) continuous real-time guidance (Illumisite™; Medtronic, Minneapolis, MN, USA). There are currently no clinical data on the diagnostic yield and safety profile of this system.

OBJECTIVES

The primary objective of this study is to describe the diagnostic yield of the first 100 pulmonary parenchymal lesions sampled using the multimodality navigation bronchoscopy (MNB) platform. The secondary objective is to describe safety.

METHODS

In this single-center prospective observational study, a database was maintained to track patient, procedural, and outcome data for the first 100 consecutive lesions sampled using the MNB platform at an academic quaternary referral center. Descriptive statistics and univariate and multivariate analyses are reported.

RESULTS

The overall diagnostic yield of samples acquired was 79% (79/100). In the cohort where digital tomosynthesis was used, the diagnostic yield was 83% (69/83). Sensitivity for malignancy was 71% (52/73). Overall complication rates were low: pneumothorax (n = 3, 3%) and bleeding requiring intervention (n = 2, 2%). There were no procedural-related hospital admissions.

CONCLUSIONS

The MNB system performed favorably. Platform superiority cannot be established without future prospective and comparative studies.

Venovenous extracorporeal membrane oxygenation during high-risk airway interventions

OBJECTIVES

Practice patterns for the use of extracorporeal membrane oxygenation (ECMO) during high-risk airway interventions vary, and data are limited. We aim to characterize our recent experience using ECMO for procedural support during whole-lung lavage (WLL) and high-risk bronchoscopy for central airway obstruction (CAO).

METHODS

We performed a retrospective cohort study of adults who received ECMO during WLL and high-risk bronchoscopy from 1 July 2018 to 30 March 2020. Our primary end point was successful completion of the intervention. Secondary end points included ECMO-associated complications and hospital survival.

RESULTS

Eight patients received venovenous ECMO for respiratory support during 9 interventions; 3 WLLs for pulmonary alveolar proteinosis were performed in 2 patients, and 6 patients underwent 6 bronchoscopic interventions for CAO. We initiated ECMO prior to the intervention in 8 cases and during the intervention in 1 case for respiratory decompensation. All 9 interventions were successfully completed. Median ECMO duration was 17.8 h (interquartile range, 15.9-26.6) for the pulmonary alveolar proteinosis group and 1.9 h (interquartile range, 1.4-8.1) for the CAO group. There was 1 cannula-associated deep vein thrombosis; there were no other ECMO complications. Seven patients (87.5%) and 4 (50.0%) patients survived to discharge and 1 year postintervention, respectively.

CONCLUSIONS

Use of venovenous ECMO to facilitate high-risk airway interventions is safe and feasible. Planned preprocedural ECMO initiation may prevent avoidable respiratory emergencies and extend therapeutic airway interventions to patients otherwise considered too high risk to treat. Guidelines are needed to inform the utilization of ECMO during high-risk bronchoscopy and other airway interventions.

A 56-Year-Old Man With Chronic Cough, Hemoptysis, and a Left Lower Lobe Infiltrate

CASE PRESENTATION

A 56-year-old man presented to the lung nodule clinic with abnormal chest imaging prompted by a chronic cough and hemoptysis. Approximately 2.5 years earlier, while kneeling beside his car fixing a flat tire, he fell backwards while holding the tire cap in his mouth, causing him to inhale sharply and aspirate the cap. He immediately developed an intractable cough productive of flecks of blood. He presented to an emergency room but left before being seen because of a long wait time and his lack of health-care insurance. He self-medicated for severe cough and chest discomfort with codeine, eventually developing a dependency. Approximately 3 weeks after aspirating the tire cap, his cough became productive, and he developed fever and chills. His symptoms improved transiently with antibiotics and additional narcotics. Ultimately, his chronic cough with intermittent hemoptysis affected his ability to work, and 30 months later he sought medical attention and was diagnosed with pneumonia and reactive airway disease. He was prescribed doxycycline, steroids, inhaled albuterol, and dextromethorphan, with initial improvement, but his symptoms recurred multiple times despite quitting smoking, leading to repeated medication courses.

Association of Social Determinants of Health with Time to Diagnosis and Treatment Outcomes in Idiopathic Subglottic Stenosis

OBJECTIVES

To examine whether social determinants of health (SDH) factors are associated with time to diagnosis, treatment selection, and time to recurrent surgical intervention in idiopathic subglottic stenosis (iSGS) patients.

METHODS

Adult patients with diagnosed iSGS were recruited prospectively (2015-2017) via clinical providers as part of the North American Airway Collaborative (NoAAC) and via an online iSGS support community on Facebook. Patient-specific SDH factors included highest educational attainment (self-reported), median household income (matched from home zip code via U.S. Census data), and number of close friends (self-reported) as a measure of social support. Main outcomes of interest were time to disease diagnosis (years from symptom onset), treatment selection (endoscopic dilation [ED] vs cricotracheal resection [CTR] vs endoscopic resection with adjuvant medical therapy [ERMT]), and time to recurrent surgical intervention (number of days from initial surgical procedure) as a surrogate for disease recurrence.

RESULTS

The total 810 participants were 98.5% female, 97.2% Caucasian, and had a median age of 50 years (IQR, 43-58). The cohort had a median household income of $62 307 (IQR, $50 345-$79 773), a median of 7 close friends (IQR, 4-10), and 64.7% of patients completed college or graduate school. Education, income, and number of friends were not associated with time to diagnosis via multivariable linear regression modeling. Univariable multinominal logistic regression demonstrated an association between education and income for selecting ED versus ERMT, but no associations were noted for CTR. No associations were noted for time to recurrent surgical procedure via Kaplan Meier modeling and Cox proportional hazards regression.

CONCLUSIONS

Patient education, income, and social support were not associated with time to diagnosis or time to disease recurrence. This suggests additional patient, procedure, or disease-specific factors contribute to the observed variations in iSGS surgical outcomes.

Comparative Treatment Outcomes for Patients With Idiopathic Subglottic Stenosis

Question

What are the outcomes of the 3 most common surgical approaches for idiopathic subglottic stenosis (iSGS)?

Findings

In this cohort study of 810 patients with iSGS who underwent 1 of the 3 most common surgical treatments, 23% of patients underwent a recurrent surgical procedure during the 3-year study period, but recurrence differed by modality (cricotracheal resection, 1%; endoscopic resection with adjuvant medical therapy, 12%; and endoscopic dilation, 28%). Among successfully treated patients, those who underwent cricotracheal resection reported the highest quality of life but the greatest perioperative risk and worst long-term voice outcomes.

Meaning

These results show the feasibility of integrating an engaged rare disease community with a network of surgeons to facilitate rapid and nuanced treatment comparisons; findings may help inform treatment decision-making in iSGS.

Importance

Surgical treatment comparisons in rare diseases are difficult secondary to the geographic distribution of patients. Fortunately, emerging technologies offer promise to reduce these barriers for research.

Objective

To prospectively compare the outcomes of the 3 most common surgical approaches for idiopathic subglottic stenosis (iSGS), a rare airway disease.

Design, Setting, and Participants

In this international, prospective, 3-year multicenter cohort study, 810 patients with untreated, newly diagnosed, or previously treated iSGS were enrolled after undergoing a surgical procedure (endoscopic dilation [ED], endoscopic resection with adjuvant medical therapy [ERMT], or cricotracheal resection [CTR]). Patients were recruited from clinician practices in the North American Airway Collaborative and an online iSGS community on Facebook.

Main Outcomes and Measures

The primary end point was days from initial surgical procedure to recurrent surgical procedure. Secondary end points included quality of life using the Clinical COPD (chronic obstructive pulmonary disease) Questionnaire (CCQ), Voice Handicap Index-10 (VHI-10), Eating Assessment Test-10 (EAT-10), the 12-Item Short-Form Version 2 (SF-12v2), and postoperative complications.

Results

Of 810 patients in this cohort, 798 (98.5%) were female and 787 (97.2%) were white, with a median age of 50 years (interquartile range, 43-58 years). Index surgical procedures were ED (n = 603; 74.4%), ERMT (n = 121; 14.9%), and CTR (n = 86; 10.6%). Overall, 185 patients (22.8%) had a recurrent surgical procedure during the 3-year study, but recurrence differed by modality (CTR, 1 patient [1.2%]; ERMT, 15 [12.4%]; and ED, 169 [28.0%]). Weighted, propensity score–matched, Cox proportional hazards regression models showed ED was inferior to ERMT (hazard ratio [HR], 3.16; 95% CI, 1.8-5.5). Among successfully treated patients without recurrence, those treated with CTR had the best CCQ (0.75 points) and SF-12v2 (54 points) scores and worst VHI-10 score (13 points) 360 days after enrollment as well as the greatest perioperative risk.

Conclusions and Relevance

In this cohort study of 810 patients with iSGS, endoscopic dilation, the most popular surgical approach for iSGS, was associated with a higher recurrence rate compared with other procedures. Cricotracheal resection offered the most durable results but showed the greatest perioperative risk and the worst long-term voice outcomes. Endoscopic resection with medical therapy was associated with better disease control compared with ED and had minimal association with vocal function. These results may be used to inform individual patient treatment decision-making.

Cryobiopsy With Radial UltraSound Guidance (CYRUS): A Pilot Randomized Controlled Study

BACKGROUND

Major airway bleeding is the most feared complication of transbronchial cryobiopsy (TBC). Radial endobronchial ultrasound (REBUS) has been used to assess the peripheral lung, primarily to identify pulmonary nodules, and also peripheral blood vessels. Using REBUS-guided TBC to avoid peripheral vasculature might reduce bleeding risk. This prospective randomized double-blind pilot trial was designed to investigate the feasibility of study procedures and inform the power calculation and clinical significance of a future large randomized trial.

METHODS

Consecutive TBCs were randomized to be performed with or without REBUS guidance in the same patient. A nonblinded operator obtained each biopsy while a blinded second operator managed the bleeding after each biopsy and determined when hemostasis had been obtained. Feasibility of study procedures and the ability to recruit patients were of primary interest. Time to hemostasis after each biopsy was also examined.

RESULTS

Forty TBCs were performed in 10 patients (4 biopsies per patient) over an enrollment period of 6 months. The time to control bleeding between biopsies was not statistically different between intervention and control arms [-14.3 (-120.1 to 92.0) s, P=0.7878]. Mean bleeding time was 139.4±59.895 seconds (REBUS 132.25± 89.305 s, non-REBUS 146.55±82.043 s). A trend towards the decreased grade of bleeding and less need for additional interventions was observed with REBUS use, but this difference did not reach statistical significance in this pilot investigation.

CONCLUSION

Our findings suggest that REBUS-guided TBC is feasible. We did not observe any statistically significant difference in time to hemostasis or bleeding grade in this pilot study.

Medical thoracoscopy in the diagnosis of pleural disease: a guide for the clinician

INTRODUCTION

Developing a feasible and accurate means of evaluating pleural pathology has been an ongoing effort for over 150 years. Pleural fluid cellular and biomarker analyses are simple ways of characterizing and uncovering pathologic entities of pleural disease. However, obtaining samples of pleural tissue has become increasingly important. In cases of suspected malignancy and certain infections histopathology, culture, and molecular testing are necessary to profile diseases more effectively. The pleura is sampled via several techniques including blind transthoracic biopsy, image-guided biopsy, and surgical thoracotomy. Given the heterogeneity of pleural disease, low diagnostic yields, or invasiveness no procedural gold standard has been established in pleural diagnostics.

AREAS COVERED

Herein, we provide a review of the literature on medical thoracoscopy (MT), its development, technical approach, indications, risks, current and future role in the evaluation of thoracic disease. Pubmed was searched for articles published on MT, awake thoracoscopy, and pleuroscopy with a focus on reviewing literature published in the past 5 years.

EXPERT OPINION

As the proficiency and number of interventional pulmonologists continues to grow, MT is ideally positioned to become a front-line diagnostic tool in pleural disease and play an increasingly prominent role in the treatment algorithm of various pleural pathologies.

Bronchoscopic biopsy of peripheral pulmonary lesions in 2020: a review of existing technologies

There are over 200,000 new cases of lung cancer diagnosed annually in the United States resulting in nearly 150,000 deaths, making lung cancer the most lethal of all forms of cancer. Only 1 in 6 lung cancers are diagnosed at an early stage an over half are diagnosed with distant metastasis. Despite advances in screening and treatment, the 5-year survival rate for all lung cancers remains low, around 20%. The advent of effective lung cancer screening with low-dose computed tomography has started to shift diagnosis to earlier stages. Screening, along with the ever-increasing use of chest CT, have led to an exponential increase in the detection of indeterminate lung nodules. For many nodules, effective diagnosis relies on invasive tissue sample collection. Advances in bronchoscopic technology have allowed for safe and increasingly effective tissue diagnosis of these nodules; however, inconsistencies across studies evaluating diagnostic yield remain. This review will provide an overview of the advanced bronchoscopic technologies currently in wide use, the quality of data supporting their use, some of the perceived weaknesses and strengths of each technology, and introduce promising emerging diagnostic platforms poised to advance the field. Ultimately, quality comparative research is needed to accurately characterize the diagnostic test performance of currently available bronchoscopic platforms, improve the efficacy of bronchoscopy-generated diagnostic yields while maintaining, their strong safety profile.

Standardized Definitions of Bleeding After Transbronchial Lung Biopsy: A Delphi Consensus Statement From the Nashville Working Group

BACKGROUND

Transbronchial lung biopsies are commonly performed for a variety of indications. Although generally well tolerated, complications such as bleeding do occur. Description of bleeding severity is crucial both clinically and in research trials; to date, there is no validated scale that is widely accepted for this purpose. Can a simple, reproducible tool for categorizing the severity of bleeding after transbronchial biopsy be created?

METHODS

Using the modified Delphi method, an international group of bronchoscopists sought to create a new scale tailored to assess bleeding severity among patients undergoing flexible bronchoscopy with transbronchial lung biopsies. Cessation criteria were specified a priori and included reaching > 80% consensus among the experts or three rounds, whichever occurred first.

RESULTS

Thirty-six expert bronchoscopists from eight countries, both in academic and community practice settings, participated in the creation of the scale. After the live meeting, two iterations were made. The second and final scale was vetted by all 36 participants, with a weighted average of 4.47/5; 53% were satisfied, and 47% were very satisfied. The panel reached a consensus and proposes the Nashville Bleeding Scale.

CONCLUSIONS

The use of a simplified airway bleeding scale that can be applied at bedside is an important, necessary tool for categorizing the severity of bleeding. Uniformity in reporting clinically significant airway bleeding during bronchoscopic procedures will improve the quality of the information derived and could lead to standardization of management. In addition to transbronchial biopsies, this scale could also be applied to other bronchoscopic procedures, such as endobronchial biopsy or endobronchial ultrasound-guided needle aspiration.

The Impact of Gravity vs Suction-driven Therapeutic Thoracentesis on Pressure-related Complications: The GRAVITAS Multicenter Randomized Controlled Trial

BACKGROUND

Thoracentesis can be accomplished by active aspiration or drainage with gravity. This trial investigated whether gravity drainage could protect against negative pressure-related complications such as chest discomfort, re-expansion pulmonary edema, or pneumothorax compared with active aspiration.

METHODS

This prospective, multicenter, single-blind, randomized controlled trial allocated patients with large free-flowing effusions estimated ≥ 500 mL 1:1 to undergo active aspiration or gravity drainage. Patients rated chest discomfort on 100-mm visual analog scales prior to, during, and following drainage. Thoracentesis was halted at complete evacuation or for persistent chest discomfort, intractable cough, or other complication. The primary outcome was overall procedural chest discomfort scored 5 min following the procedure. Secondary outcomes included measures of discomfort and breathlessness through 48 h postprocedure.

RESULTS

A total of 142 patients were randomized to undergo treatment, with 140 in the final analysis. Groups did not differ for the primary outcome (mean visual analog scale score difference, 5.3 mm; 95% CI, -2.4 to 13.0; P = .17). Secondary outcomes of discomfort and dyspnea did not differ between groups. Comparable volumes were drained in both groups, but the procedure duration was significantly longer in the gravity arm (mean difference, 7.4 min; 95% CI, 10.2 to 4.6; P < .001). There were no serious complications.

CONCLUSIONS

Thoracentesis via active aspiration and gravity drainage are both safe and result in comparable levels of procedural comfort and dyspnea improvement. Active aspiration requires less total procedural time.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03591952; URL: www.clinicaltrials.gov.

Improved diagnostic yield for lung nodules with digital tomosynthesis-corrected navigational bronchoscopy: Initial experience with a novel adjunct

BACKGROUND AND OBJECTIVE

The diagnostic yield of electromagnetic navigation bronchoscopy (ENB) is inferior to that of computed tomography (CT)-guided needle biopsy for pulmonary nodules. One explanation for this is divergence between the nodule location on the pre-procedure CT scan and its actual location during the procedure. Fluoroscopic ENB (F-ENB) consists of digital tomosynthesis using a conventional C-arm to re-register the target lesion based on near real-time imaging. We performed a retrospective review of ENB cases at our institution before and after introduction of F-ENB to assess diagnostic yield.

METHODS

All consecutive ENB procedures performed at our institution from 25 December 2017 to 25 August 2018 were reviewed. F-ENB was introduced on 25 April 2018. Two cohorts were analysed: standard ENB (S-ENB) from 25 December 2017 to 24 April 2018 and F-ENB from 25 April 2018 to 25 August 2018. All procedural, demographic and diagnostic data were collected. Descriptive statistics, chi-square, Wilcoxon test and Student's t-test were used where appropriate. A multivariable regression analysis was performed to assess factors associated with diagnostic yield.

RESULTS

A total of 101 and 67 nodules were biopsied in the S-ENB and F-ENB groups, respectively. Diagnostic yield was 54% in S-ENB cohort and 79% in the F-ENB group (P = 0.0019). Factors independently associated with a positive diagnosis were F-ENB and a positive radial ultrasound view (odds ratio (OR): 3.57, 95% CI: 1.56-8.18 and OR: 3.74, 95% CI: 1.37-11.05, respectively). Complications were minimal (pneumothorax: 1.5%).

CONCLUSION

The use of F-ENB may increase the diagnostic yield of ENB and has a low complication rate.

Interstitial Pneumonia With Autoimmune Features: An Emerging Challenge at the Intersection of Rheumatology and Pulmonology

Interstitial lung disease (ILD) remains a cause of significant morbidity and mortality in patients with connective tissue disease (CTD)-associated ILD. While some patients meet clear classification criteria for a systemic rheumatic disease, a subset of patients do not meet classification criteria but still benefit from immunosuppressive therapy. In 2015, the American Thoracic Society and European Respiratory Society described classification criteria for interstitial pneumonia with autoimmune features (IPAF) to identify patients with lung-predominant CTD who lack sufficient features of a systemic rheumatic disease to meet classification criteria. Although these criteria are imperfect, they are an important attempt to classify the patient with undifferentiated disease for future study. Rheumatologists play a key role in the evaluation of potential IPAF in patients, especially as many patients with a myositis-spectrum disease (e.g., non-Jo-1 antisynthetase syndrome, anti-melanoma differentiation-associated protein 5 antibody inflammatory myositis, or anti-PM/Scl antibody-associated inflammatory myositis) would be classified under IPAF using the currently available criteria for inflammatory myositis, and would therefore benefit from rheumatologic comanagement. The aim of this review was to describe the historical context that led to the development of these criteria and to discuss the limitations of the current criteria, diagnostic challenges, treatment options, and strategies for disease monitoring.

Two cases of Dieulafoy lesions of the bronchus with novel comorbid associations and endobronchial ablative management

RATIONALE

Dieulafoy lesions are aberrantly large submucosal arteries most frequently associated with gastrointestinal hemorrhage. They are rarely identified in the bronchial submucosa and can cause massive hemoptysis.

PATIENT CONCERNS

We present three episodes of massive hemoptysis in two patients, the first with comorbid Alagille syndrome including multiple cardiac and pulmonary vascular abnormalities and the second with thyroid cancer metastatic to the mediastinum.

DIAGNOSES

All episodes were due to Dieulafoy lesions of the bronchus based on bronchoscopic appearance.

INTERVENTIONS

Bronchoscopic ablation using Nd:YAP laser was attempted both patients.

OUTCOMES

Nd:YAP laser successfully ablated the Dieulafoy lesion in the first case with long-term relief from recurrent hemoptysis. The first episode in the second patient responded to bronchial artery embolization; laser ablation of a different Dieulafoy lesion responsible for the second episode was unsuccessful but additional bronchial artery embolization has provided relief from further episodes.

LESSONS

Bronchoscopic ablation of Dieulafoy lesions of the bronchus can provide durable relief from recurrent symptoms. Clinical and anatomical features should be considered carefully before intervention, which should only be attempted by experienced operators with appropriate ancillary support available.

A Multicenter Randomized Trial of a Checklist for Endotracheal Intubation of Critically Ill Adults

BACKGROUND

Hypoxemia and hypotension are common complications during endotracheal intubation of critically ill adults. Verbal performance of a written, preintubation checklist may prevent these complications. We compared a written, verbally performed, preintubation checklist with usual care regarding lowest arterial oxygen saturation or lowest systolic BP experienced by critically ill adults undergoing endotracheal intubation.

METHODS

A multicenter trial in which 262 adults undergoing endotracheal intubation were randomized to a written, verbally performed, preintubation checklist (checklist) or no preintubation checklist (usual care). The coprimary outcomes were lowest arterial oxygen saturation and lowest systolic BP between the time of procedural medication administration and 2 min after endotracheal intubation.

RESULTS

The median lowest arterial oxygen saturation was 92% (interquartile range [IQR], 79-98) in the checklist group vs 93% (IQR, 84-100) with usual care (P = .34). The median lowest systolic BP was 112 mm Hg (IQR, 94-133) in the checklist group vs 108 mm Hg (IQR, 90-132) in the usual care group (P = .61). There was no difference between the checklist and usual care in procedure duration (120 vs 118 s; P = .49), number of laryngoscopy attempts (one vs one attempt; P = .42), or severe life-threatening procedural complications (40.8% vs 32.6%; P = .20).

CONCLUSIONS

The verbal performance of a written, preprocedure checklist does not increase the lowest arterial oxygen saturation or lowest systolic BP during endotracheal intubation of critically ill adults compared with usual care.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02497729; URL: www.clinicaltrials.gov.

Foreign body aspiration in adult airways: therapeutic approach

Tracheobronchial foreign body (FB) aspiration is an uncommon but potentially life-threatening event in adults. Symptoms typically consist of a choking event followed by cough and dyspnea, however, these findings are inconsistent and symptoms may mimic more chronic lung diseases such as asthma or chronic obstructive pulmonary disease. Chest radiography and computed tomography can provide information regarding the location and characteristics of foreign bodies and aid in diagnosis. Bronchoscopy remains the gold standard for diagnosis and management of FB aspiration. The authors describe the typical clinical presentation, diagnostic evaluation, and bronchoscopic management of foreign bodies in adult airways with a focus on bronchoscopic techniques and potential complications of FB extraction.

Diagnostic approach to pleural diseases: new tricks for an old trade

The burden of pleural diseases has substantially increased in the past decade because of a rise in the incidence of pleural space infections and pleural malignancies in a patient population that is older and more immunocompromised and has more comorbidities. This complexity increasingly requires minimally invasive diagnostic options and tailored management. Implications for patients are such that the limitations of current diagnostic methods need to be addressed by multidisciplinary teams of investigators from the fields of imaging, biology, and engineering. Ignored for a long time as an epiphenomenon at the crossroad of many unrelated medical problems, pleural diseases are finally getting the attention they deserve and have spurred a vibrant and exciting field of research.

Transbronchial cryobiopsy for diffuse parenchymal lung disease: a state-of-the-art review of procedural techniques, current evidence, and future challenges

Transbronchial lung biopsy with a cryoprobe, or cryobiopsy, is a promising new bronchoscopic biopsy technique capable of obtaining larger and better-preserved samples than previously possible using traditional biopsy forceps. Over two dozen case series and several small randomized trials are now available describing experiences with this technique, largely for the diagnosis of diffuse parenchymal lung disease (DPLD), in which the reported diagnostic yield is typically 70% to 80%. Cryobiopsy technique varies widely between centers and this predominantly single center-based retrospective literature heterogeneously defines diagnostic yield and complications, limiting the degree to which this technique can be compared between centers or to surgical lung biopsy (SLB). This review explores the broad range of cryobiopsy techniques currently in use, their rationale, the current state of the literature, and suggestions for the direction of future study into this promising but unproven procedure.

A Multicenter, Randomized Trial of Ramped Position vs Sniffing Position During Endotracheal Intubation of Critically Ill Adults

BACKGROUND

Hypoxemia is the most common complication during endotracheal intubation of critically ill adults. Intubation in the ramped position has been hypothesized to prevent hypoxemia by increasing functional residual capacity and decreasing the duration of intubation, but has never been studied outside of the operating room.

METHODS

Multicenter, randomized trial comparing the ramped position (head of the bed elevated to 25°) with the sniffing position (torso supine, neck flexed, and head extended) among 260 adults undergoing endotracheal intubation by pulmonary and critical care medicine fellows in four ICUs between July 22, 2015, and July 19, 2016. The primary outcome was lowest arterial oxygen saturation between induction and 2 minutes after intubation. Secondary outcomes included Cormack-Lehane grade of glottic view, difficulty of intubation, and number of laryngoscopy attempts.

RESULTS

The median lowest arterial oxygen saturation was 93% (interquartile range [IQR], 84%-99%) with the ramped position vs 92% (IQR, 79%-98%) with the sniffing position (P = .27). The ramped position appeared to increase the incidence of grade III or IV view (25.4% vs 11.5%, P = .01), increase the incidence of difficult intubation (12.3% vs 4.6%, P = .04), and decrease the rate of intubation on the first attempt (76.2% vs 85.4%, P = .02), respectively.

CONCLUSIONS

In this multicenter trial, the ramped position did not improve oxygenation during endotracheal intubation of critically ill adults compared with the sniffing position. The ramped position may worsen glottic view and increase the number of laryngoscopy attempts required for successful intubation.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02497729; URL: www.clinicaltrials.gov.

Randomized Trial of Apneic Oxygenation during Endotracheal Intubation of the Critically Ill

RATIONALE

Hypoxemia is common during endotracheal intubation of critically ill patients and may predispose to cardiac arrest and death. Administration of supplemental oxygen during laryngoscopy (apneic oxygenation) may prevent hypoxemia.

OBJECTIVES

To determine if apneic oxygenation increases the lowest arterial oxygen saturation experienced by patients undergoing endotracheal intubation in the intensive care unit.

METHODS

This was a randomized, open-label, pragmatic trial in which 150 adults undergoing endotracheal intubation in a medical intensive care unit were randomized to receive 15 L/min of 100% oxygen via high-flow nasal cannula during laryngoscopy (apneic oxygenation) or no supplemental oxygen during laryngoscopy (usual care). The primary outcome was lowest arterial oxygen saturation between induction and 2 minutes after completion of endotracheal intubation.

MEASUREMENTS AND MAIN RESULTS

Median lowest arterial oxygen saturation was 92% with apneic oxygenation versus 90% with usual care (95% confidence interval for the difference, -1.6 to 7.4%; P = 0.16). There was no difference between apneic oxygenation and usual care in incidence of oxygen saturation less than 90% (44.7 vs. 47.2%; P = 0.87), oxygen saturation less than 80% (15.8 vs. 25.0%; P = 0.22), or decrease in oxygen saturation greater than 3% (53.9 vs. 55.6%; P = 0.87). Duration of mechanical ventilation, intensive care unit length of stay, and in-hospital mortality were similar between study groups.

CONCLUSIONS

Apneic oxygenation does not seem to increase lowest arterial oxygen saturation during endotracheal intubation of critically ill patients compared with usual care. These findings do not support routine use of apneic oxygenation during endotracheal intubation of critically ill adults. Clinical trial registered with www.clinicaltrials.gov (NCT 02051816).