Trajectories of hypoxemia and pulmonary mechanics of COVID-19 ARDS in the NorthCARDS dataset.

BACKGROUND: Understanding heterogeneity seen in patients with COVIDARDS and comparing to non-COVIDARDS may inform tailored treatments. METHODS: A multidisciplinary team of frontline clinicians and data scientists worked to create the Northwell COVIDARDS dataset (NorthCARDS) leveraging over 11,542 COVID-19 hospital admissions. The data was then summarized to examine descriptive differences based on clinically meaningful categories of lung compliance, and to examine trends in oxygenation. FINDINGS: Of the 1536 COVIDARDS patients in the NorthCARDS dataset, there were 531 (34.6%) who had very low lung compliance (< 20 ml/cmH2O), 970 (63.2%) with low-normal compliance (20-50 ml/cmH2O), and 35 (2.2%) with high lung compliance (> 50 ml/cmH2O). The very low compliance group had double the median time to intubation compared to the low-normal group (107.3 h (IQR 25.8, 239.2) vs. 39.5 h (IQR 5.4, 91.6)). Overall, 68.8% (n = 1057) of the patients died during hospitalization. In comparison to non-COVIDARDS reports, there were less patients in the high compliance category (2.2% vs. 12%, compliance ≥ 50 mL/cmH20), and more patients with P/F ≤ 150 (59.8% vs. 45.6%). There is a statistically significant correlation between compliance and P/F ratio. The Oxygenation Index is the highest in the very low compliance group (12.51, SD(6.15)), and lowest in high compliance group (8.78, SD(4.93)). CONCLUSIONS: The respiratory system compliance distribution of COVIDARDS is similar to non-COVIDARDS. In some patients, there may be a relation between time to intubation and duration of high levels of supplemental oxygen treatment on trajectory of lung compliance.

Assessment of Diaphragm Function and Pleural Pressures During Thoracentesis.

BACKGROUND: This prospective observational study reports on diaphragm excursion, velocity of diaphragm contraction, and changes in pleural pressure that occur with thoracentesis. METHODS: Twenty-eight patients with pleural effusion underwent therapeutic thoracentesis. Diaphragm excursion and velocity of diaphragm contraction were measured with M-mode ultrasonography of the affected hemidiaphragm. Pleural pressure was measured at each aliquot of 250 mL of fluid removal. Fluid removal was continued until no more fluid could be withdrawn, unless there was evidence of nonexpandable lung defined as a pleural elastance greater > 14.5 cm H2O/L and/or ipsilateral anterior chest discomfort. RESULTS: Twenty-three patients had expandable lung, and five patients had nonexpandable lung. Velocity of diaphragm contraction (mean ± SD) increased from 1.5 ± 0.4 cm/s to 2.8 ± 0.4 cm/s pre-thoracentesis and post-thoracentesis, respectively (CI, 0.93-1.61; P < .001) in subjects with expandable lung. Velocity of diaphragm contraction (mean ± SD) increased from 2.0 ± 0.4 cm/s to 2.3 ± 0.4 cm/s pre-thoracentesis and post-thoracentesis (P = .45) in subjects with nonexpandable lung. Diaphragm excursion was significantly increased in subjects with expandable lung at the end of thoracentesis; diaphragm excursion did not increase to a significant extent in patients with nonexpandable lung. CONCLUSIONS: The velocity of diaphragm contraction and diaphragm excursion increased in association with fluid removal with thoracentesis in patients with expandable lung, whereas it did not significantly change in patients with nonexpandable lung. This may derive from improvement in loading conditions of the diaphragm in patients with expandable lung related to its preload and length-tension characteristics.

Critical Care Airway Management.

Critical care airway management is associated with a variety of complications, including severe oxygen desaturation, life-threatening hypotension, and death. This article reviews aspects of airway management that are relevant to intensivists and emergency medicine clinicians tasked with improving the quality of urgent endotracheal intubation in the critically ill patient.

Defining a Ventilation Strategy for Flexible Bronchoscopy on Mechanically Ventilated Patients in the Medical Intensive Care Unit.

BACKGROUND: Flexible bronchoscopy (FB) in intubated patients on mechanical ventilation increases airway resistance. During FB, two ventilatory strategies are possible: maintaining tidal volume (VT) while maintaining baseline CO2 or allowing reduction of VT. The former strategy carries risk of hyperinflation due to expiratory flow limitation with FB. The aim of the authors was too study end expiratory lung volume (EELV) during FB of intubated subjects while limiting VT. METHODS: We studied 16 subjects who were intubated on mechanical ventilation and required FB. Changes in EELV were measured by respiratory inductance plethysmography. Ventilator mechanics, EELV, and arterial blood gases, were measured. RESULTS: FB insertions decreased EELV in 64% of cases (-325±371 mL) and increased it in 32% of cases (65±59 mL). Suctioning decreased EELV in 76% of cases (-120±104 mL) and increased it in 16% of cases (29±33 mL). Respiratory mechanics were unchanged. Pre-FB and post-FB, PaO2 decreased by 61±96 mm Hg and PaCO2 increased by 15±7 mm Hg. CONCLUSIONS: There was no clinically significant increase in EELV in any subject during FB. Decreases in EELV coincided with FB-suctioning maneuvers. Peak pressure limiting ventilation protected the subject against hyperinflation with a consequent, well-tolerated reduction in VT, and hypercapnea. Suctioning should be limited, especially in patients vulnerable to derecruitment effect.

Ultrasonography in the emergency department.

Point-of-care ultrasonography (POCUS) is a useful imaging technique for the emergency medicine (EM) physician. Because of its growing use in EM, this article will summarize the historical development, the scope of practice, and some evidence supporting the current applications of POCUS in the adult emergency department. Bedside ultrasonography in the emergency department shares clinical applications with critical care ultrasonography, including goal-directed echocardiography, echocardiography during cardiac arrest, thoracic ultrasonography, evaluation for deep vein thrombosis and pulmonary embolism, screening abdominal ultrasonography, ultrasonography in trauma, and guidance of procedures with ultrasonography. Some applications of POCUS unique to the emergency department include abdominal ultrasonography of the right upper quadrant and appendix, obstetric, testicular, soft tissue/musculoskeletal, and ocular ultrasonography. Ultrasonography has become an integral part of EM over the past two decades, and it is an important skill which positively influences patient outcomes.

Simulation for Skills-based Education in Pulmonary and Critical Care Medicine.

The clinical practice of pulmonary and critical care medicine requires procedural competence in many technical domains, including vascular access, airway management, basic and advanced bronchoscopy, pleural procedures, and critical care ultrasonography. Simulation provides opportunities for standardized training and assessment in procedures without placing patients at undue risk. A growing body of literature supports the use and effectiveness of low-fidelity and high-fidelity simulators for procedural training and assessment. In this manuscript by the Skills-based Working Group of the American Thoracic Society Education Committee, we describe the background, available technology, and current evidence related to simulation-based skills training within pulmonary and critical care medicine. We outline working group recommendations for key procedural domains.

Video laryngoscopy is associated with increased first pass success and decreased rate of esophageal intubations during urgent endotracheal intubation in a medical intensive care unit when compared to direct laryngoscopy.

BACKGROUND: To compare the complication rates of urgent endotracheal intubation (UEI) performed by pulmonary critical care medicine (PCCM) fellows and attending intensivists using a direct laryngoscope (DL) versus a video laryngoscope (VL) in a medical intensive care unit (MICU). METHODS: We studied all UEIs performed from November 2008 through July 2012 in an 18-bed MICU in a university-affiliated hospital. All UEIs were performed by 15 PCCM fellows or attending intensivists using only the DL from November 2008 through February 2010 and the VL from March 2010 to July 2012. Throughout the entire study period, the UEI team leader recorded complications of the procedure using a standard data collection form immediately following the completion of the procedure. This permitted a comparison of complication rates between the DL and the VL. RESULTS: A total of 140 UEIs were performed using the DL and 252 using the VL. Using the DL, the esophageal intubation rate was 19% and the difficult intubation rate was 22%; using the VL, the esophageal intubation rate was 0.4% and the difficult intubation rate was 7%. There was no significant difference in the rate of severe hypotension, severe desaturation, aspiration, dental injury, airway injury, or death between the 2 groups. CONCLUSION: The use of the VL for UEI performed by PCCM fellows is associated with a reduction in the rate of esophageal intubation and difficult endotracheal intubation when compared to the use of the DL.

The impact of video laryngoscopy use during urgent endotracheal intubation in the critically ill.

BACKGROUND: The video laryngoscope (VL) has been shown to improve laryngoscopic views and first-attempt success rates in elective operating room and simulated tracheal intubations compared with the direct laryngoscope (DL). However, there are limited data on the effectiveness of the VL compared with the DL in urgent endotracheal intubations (UEIs) in the critically ill. We assessed the effectiveness of using a VL as the primary intubating device during UEI in critically ill patients when performed by less experienced operators. METHODS: We compared success rates of UEIs performed by Pulmonary and Critical Care Medicine (PCCM) fellows in the medical intensive care unit and medical or surgical wards. A cohort of PCCM fellows using GlideScope VL as the primary intubating device was compared with a historical cohort of PCCM fellows using a traditional Macintosh or Miller blade DL. The primary measured outcome was first-attempt intubation success rate. Secondary outcomes included total number of attempts required for successful tracheal intubation, rate of esophageal intubation, need for supervising attending intervention, duration of intubation sequence, and incidence of hypoxemia and hypotension. RESULTS: There were 138 UEIs, with 78 using a VL and 50 using a DL as the primary intubating device. The rate of first-attempt success was superior with the VL as compared with the DL (91% vs 68%, P < 0.01). The rate of intubations requiring ≥3 attempts (4% vs 20%, P < 0.01), unintended esophageal intubations (0% vs 14%, P < 0.01), and the average number of attempts required for successful tracheal intubation (1.2 ± 0.56 vs 1.7 ± 1.1, P < 0.01) all improved significantly with use of the VL compared with the DL. CONCLUSIONS: UEI using a VL as the primary device improved intubation success and decreased complications compared with a DL when PCCM fellows were the primary operators. These data suggest that the VL should be used as the primary device when urgent intubations are performed by less experienced operators.

Thoracic ultrasonography for the pulmonary specialist.

Thoracic ultrasonography is a noninvasive and readily available imaging modality that has important applications in pulmonary medicine outside of the ICU. It allows the clinician to diagnose a variety of thoracic disorders at the point of care. Ultrasonography is useful in imaging lung consolidation, pleural-based masses and effusions, pneumothorax, and diaphragmatic dysfunction. It can identify complex or loculated effusions and be useful in planning treatment. Identifying intrathoracic mass lesions can guide sampling by aspiration and biopsy. This article summarizes thoracic ultrasonography applications for the pulmonary specialist, related procedural codes, and reimbursement. The major concepts are illustrated with cases. These case summaries are enhanced with online supplemental videos and chest radiograph, chest CT scan, and ultrasound correlation.

ACCF/ASE/ACEP/AHA/ASNC/SCAI/SCCT/SCMR 2008 appropriateness criteria for stress echocardiography: a report of the American College of Cardiology Foundation Appropriateness Criteria Task Force, American Society of Echocardiography, American College of Emergency Physicians, American Heart Association, American Society of Nuclear Cardiology, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance: endorsed by the Heart Rhythm Society and the Society of Critical Care Medicine.

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.

ACCF/ASE/ACEP/AHA/ASNC/SCAI/SCCT/SCMR 2008 appropriateness criteria for stress echocardiography: a report of the American College of Cardiology Foundation Appropriateness Criteria Task Force, American Society of Echocardiography, American College of Emergency Physicians, American Heart Association, American Society of Nuclear Cardiology, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance endorsed by the Heart Rhythm Society and the Society of Critical Care Medicine.

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.

Effect of thoracentesis on respiratory mechanics and gas exchange in the patient receiving mechanical ventilation.

BACKGROUND: This study reports the effect of thoracentesis on respiratory mechanics and gas exchange in patients receiving mechanical ventilation. STUDY DESIGN: Prospective. SETTING: University hospital. PATIENTS: Eight patient receiving mechanical ventilation with unilateral (n = 7) or bilateral (n = 1) large pleural effusions. INTERVENTION: Therapeutic thoracentesis (n = 9). MEASUREMENTS: Resistances of the respiratory system measured with the constant inspiratory flow interrupter method measuring peak pressure and plateau pressure, effective static compliance of the respiratory system (Cst,rs), work performed by the ventilator (Wv), arterial blood gases, mixed exhaled Pco2, and pleural liquid pressure (Pliq). RESULTS: Thoracentesis resulted in a significant decrease in Wv and Pliq. Thoracentesis had no significant effect on dynamic compliance of the respiratory system; Cst,rs; effective interrupter resistance of the respiratory system, or its subcomponents, ohmic resistance of the respiratory system and additional (non-ohmic) resistance of the respiratory system; or intrinsic positive end-expiratory pressure (PEEPi). Indices of gas exchange were not significantly changed by thoracentesis. CONCLUSIONS: Thoracentesis in patients receiving mechanical ventilatory support results in significant reductions of Pliq and Wv. These changes were not accompanied by significant changes of resistance or compliance or by significant changes in gas exchange immediately after thoracentesis. The reduction of Wv after thoracentesis in patients receiving mechanical ventilation is not accompanied by predictable changes in inspiratory resistance and static compliance measured with routine clinical methods. The benefit of thoracentesis may be most pronounced in patients with high levels of PEEPi.