Bedside Ultrasound for the diagnosis of ALI ARDS Chief of Medicine Conference 10/29/2013 Cameron Bass, MD
Disclosures Mobisante ™ provided me with one of their smartphone based ultrasound devices for use in the study The UWMC pays my salary, so I suppose I’m less likely to say bad things about them publically I haven’t brushed my hair in almost a full year
Outline Background on Cameron Critical Illness in the resource limited setting ARDS review Ultrasound – Basic review – Pulmonary ultrasound Pulse oximetry Bedside Ultrasound for the diagnosis of ARDS – Methods – Challenges – Future directions Brilliant and incisive Q&A
A Brief Introduction to Cameron Engineering Rwanda
Critical Illness in the Resource Limited Setting Resource allocation – Cost of Critical Care – Faith in the system 1 – A lack of knowledge 2
Critical Illness in the Resource Limited Setting Appropriate use of technology – Ventilators – Ultrasound 3
Critical Illness in the Resource Limited Setting Developing vs third world vs resource limited
Brief Introduction to ARDS Initial description in 1967 by Ashbaugh 4 New definition in 1994 by AECCC 5 – P:F ratio – Bilateral infiltrates on CXR (“A pulmonary Edema pattern”) – PCWP < 18mm Hg Berlin definition in – Risk factors – Timing
Prevalence of ARDS In the united states – >150,000 cases per year 7 In the resource limited setting – Challenges to diagnosis – Differences in etiology
1540 m/s You know what happens when you make an assumption? (Samuel L Jackson) Reverberation artifact Comet tail artifact How ultrasound works cartoon
Pulmonary Ultrasound Lung Sliding Videos courtesy
Pulmonary Ultrasound A lack of Lung Sliding Videos courtesy
Pulmonary Ultrasound A lines 8 Videos courtesy
Pulmonary Ultrasound B lines 8 Videos courtesy
Thoracic Ultrasound Ease of teaching 9
Thoracic Ultrasound Lichtenstein and the Blue protocol 8
BLUE protocol 8
Thoracic Ultrasound Specific studies for ARDS – BLUE protocol 8 – FALLS protocol – ARDS vs Acute Pulmonary Edema 10
Arterial Blood Gasses Cost of performing – Estimated at $110 cost to patient SpO 2 to ABG – In adults 11 S/F = x (P/F) [p < ; r = 0.89) S/F of 235 ≈ P/F of 200 S/F of 315 ≈ P/F of 300 – In pediatrics 12 S/F = x PF (p < , R 2 = 0.61) S/F 201 ≈ P/F of 200 S/F 263 ≈ P/F of 300
Bedside Ultrasound for the diagnosis of ARDS Study Design
Bedside Ultrasound for the diagnosis of ARDS Scanning – Technique – Mobisante
Bedside Ultrasound for the diagnosis of ARDS Reviewing Data – Chest Radiographs – Ultrasound scans
Bedside Ultrasound for the diagnosis of ARDS Statistical Analysis – Lack of a Gold Standard PPA NPA Kappa
Challenges Identifying Patients Prevalence Positioning SpO2 measurements IRB/HIPAA
Future Directions Cambodia/Rwanda
Citations 1.Neill KJ Adhikari, Robert A Fowler, Satish Bhagwanjee, Gordon D Rubenfeld, Critical care and the global burden of critical illness in adults, The Lancet, Volume 376, Issue 9749, 16–22 October 2010, Pages Dünser MW, Baelani I, Ganbold L. “A review and analysis of intensive care medicine in the least developed countries.“Crit Care Med Apr;34(4): Sippel S, Muruganandan K, Levine A, Shah S. “Review article: Use of ultrasound in the developing world.” Int J Emerg Med Dec 7;4:72. doi: / Ashbaugh D, Bigelow D, Petty T, Levine B (1967). "Acute respiratory distress in adults". Lancet 2 (7511): 319–23. 5.Bernard G, Artigas A, Brigham K, Carlet J, Falke K, Hudson L, Lamy M, Legall J, Morris A, Spragg R (1994). "The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial 6.CV. Marco Ranieri, MD (2012). "The ARDS Definition Task Force*. Acute Respiratory Distress Syndrome: The Berlin Definition". JAMA 307 (23): 2526– Gordon D. Rubenfeld, MD, MSc; Margaret S. Herridge, MD, MPH, FCCP. “Epidemiology and Outcomes of Acute Lung Injury” Chest. 2007;131(2): doi: /chest Lichtenstein et al. Relevance of lung ultrasound in the diagnosis of acute respiratory failure. The BLUE-protocol. Chest 2008;134: G Bedetti 1, L Gargani 2, A Corbisiero 3, F Frassi 2, E Poggianti 2 and G Mottola*“Evaluation of ultrasound lung comets by hand-held echocardiography“ Cardiovascular Ultrasound 10.Roberto Copetti* 1, Gino Soldati 2 and Paolo Copetti. Chest sonography: a useful tool to differentiate acute cardiogenic pulmonary edema from acute respiratory distress syndrome. Cardiovascular Medicine. 29 April Rice, Wheeler, bernard et al. ARDSNET “Comparison of the Sp O 2 /F IO 2 Ratio and the Pa O 2 /F IO 2 Ratio in Patients With Acute Lung Injury or ARDS” CHEST 2007; 132:410– Robinder G. Khemani, MD, MSCI; Neal R. Patel, MD, MPH; Robert D. Bart, III, MD; and Christopher J. L. Newth, MD “Comparison of the Pulse Oximetric Saturation/Fraction of Inspired Oxygen Ratio and the Pa O 2 /Fraction of Inspired Oxygen Ratio in Children* CHEST 2009; 135: