Critical Care of the Chronic Lung Disease Patients Ivan Co, MD Assistant Professor, University of Michigan Department of Emergency Medicine- Emergency Critical Care Department of Internal Medicine- Pulmonary Critical Care Disclosures No Disclosures This lecture will not replace obtaining accurate history and physical exam to help guide you to the right diagnosis Once you get to the right diagnosis, this lecture will help you avoid common pitfalls and provide pointers that will help your practice. Thank you to the University of Michigan PCCM fellows for their input 1
Overview patients with chronic lung disease. Critical Care pearls for patients with Obstructive Lung Disease COPD Asthma Mechanical Ventilation Critical Care pearls for patients with Restrictive Lung Disease Critical Care pearls for patients with Pleural Disease patients with chronic lung disease. Right heart. Many pts with chronic lung disease have associated group 3 pulm htn so beware the right heart Hypoxic pulmonary vasoconstriction + vascular remodeling Worsens RV afterload Prevalence Pulmonary Hypertension between 20-90%. Acute on chronic hypoxic respiratory failure needs evaluation for cardiac contribution. Respect the already strained right heart especially with introduction of Positive Pressure Ventilation. Budev 2003 Klinger 2016 2
patients with chronic lung disease. If really questioning hypoxemia/hypercap nia, please put in some effort and get ABG and not just VBG. Please look at baseline serum HCO3 and past ABGs to see if they are chronic retainers before overventilating them https://lifeinthefastlane.com/investigations/acid-base/ patients with chronic lung disease. Take a quick peek at the PFTs. Getting a sense of how bad their FVC is (if restrictive disease) or FEV1 (obstructive), DLCO is helpful for determining their reserve if you need to intubate or god forbid, bronch. or hopefully inspire you to do goals of care before any of those things. 3
intubated patients with chronic lung disease. Don t wait until patients are maxed on 100% O2 to intubate if trajectory is poor. they often have poor reserve and will crash hard if you need multiple attempts intubated patients with chronic lung disease. Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy Frat et al. CCM 2018 Figure 2. Box plots showing the median delay (25-75th percentiles) in hours between noninvasive ventilation (NIV) initiation and intubation in survivors (white) and nonsurvivors (gray). This delay did not significantly differ between the two groups with a median delay of 16 hr (9-23) versus 16 (15-28) in NIV group (p = 0.40). 4
intubated patients with chronic lung disease. Biggest, most consistent error from ED is failing lung protective ventilation (6cc/kg or less to get Pplat< 30). RTs are busy and usually use TV 500cc for men, 400 for women. stop blasting fibrotic or delicate lung! LOV-ED 2017 intubated patients with chronic lung disease. Tidal Volume at 6cc/kg of IBW @ 5 feet 5 inch TV= 340 @ 5 feet 7 inch TV= 400 @ 6 feet 3 inch TV = 507 @ 7 feet TV = 630 5
Critical Care pearls for patients with Obstructive Lung Disease- COPD Mainstay treatment: Bronchodilators, Steroids and treatment of underlying cause resulting in exacerbation Keep in mind that PE is present in up to 25% of COPD exacerbations. Look at prior cultures/sensitivities -> high risk for pseudomonas, atypicals and increase abx resistance. No difference with Q6hr vs Daily Steroids for exacerbation 5 day steroid course non-inferior to 14 day course No absolute need to correct hypoxia in COPD patients beyond the 88-92% O2 saturation range. NIV is the preferred initial method of ventilatory support in COPD unless patient absolutely needs to be intubated. Woods 2014 Aleva 2017 Leuppi 2013 Critical Care pearls for patients with Obstructive Lung Disease -Asthma Mainstay treatment: Bronchodilators, Steroids and treatment of underlying cause resulting in exacerbation If possible, compared peak flows to patient's baseline peak flow Do not ignore normal ph/pco2 in a tachypneic patient in distress. Be extra vigilant in asthma patients without wheezing Kitchen sink therapeutic strategy in severe attack. Goal is to not get the patient intubated Ketamine, Epinephrine as adjust (+evidence). Magnesium, Heliox, terbutaline (+/- evidence) 6
Critical Care pearls for intubated patients with Obstructive Lung Disease Be cognizant of auto-peep. C = ΔV / ΔP Obstructive process: C = ΔV / ΔP as a result of increase ΔV (cannot exhale properly) secondary to lack of elastic recoil Increase FRC and TLC Results in airflow obstruction, incomplete exhalation, air trapping, poor gas exchange. Expiratory Hold to look for AutoPEEP (end expiratory air above set PEEP) Allow for permissive hypercapnia Air Trapping/AutoPEEP Figure 1. Relationship of auto positive endexpiratory pressure (AP) to PEEP, driving pressure, and terminal expiratory flow during pressure-controlled ventilation. Shaded areas indicate the flow driving pressure gradients during inspiration and expiration. When exhalation terminates before equilibration can be achieved between airway (Paw) and alveolar (Palv) pressures, end-expiratory flow (arrow) persists, and total PEEP exceeds the set value, producing dynamic hyperinflation that can be modified with changes of breathing pattern. Am J Respir Crit Care Med, https://www.atsjournals.org/doi/abs/10.1164/rccm.20110 2-0226PP Published in: John J. Marini; Am J Respir Crit Care Med 2011, 184, 756-762. DOI: 10.1164/rccm.201102-0226PP Copyright 2011 American Thoracic Society One PowerPoint slide of each figure may be downloaded and used for educational not promotional purposes by an author for slide presentations only. The ATS citation line must appear in at least 10-point type on all figures in all presentations. Pharmaceutical and Medical Education companies must request permission to download and use slides, and authors and/or publishing companies using the slides for new article creations for books or journals must apply for permission. For permission requests, please contact the Publisher at dgern@thoracic.org or 212-315-6441. Marini 2011 7
Critical Care pearls for intubated patients with Obstructive Lung Disease Calculate Δ P = Ppeak Pplat to understand lung physiology Δ P >10 for obstructive lung disease on ventilator Critical Care pearls for patients with Restrictive Lung Disease Manifest as Decreased FRC, TLC, FEV, FVC results high FEV/FVC ratio Can manifest as extrapulmonary, pleural, or parenchymal lung disease Look at DLCO In IPF/ILD, 3 additional investigative category for acute hypoxic respiratory failure: Opportunistic Infection (PCP) RV failure and fluid overload Pulmonary Embolism 8
Critical Care pearls for intubated patients with Restrictive Lung Disease Do not BVM ILD/IPF patients Low lung compliance causes airflow to go to path of least resistance. Gastric > pulmonary insufflation Only takes 20-25 cm H20 to open lower esophageal sphincter Mask, lung, and stomach tidal volume applied with an adult and paediatric self-inflatable bag at LESP levels of 15, 10, and 5 cm H 2 O. Bars representing lung (black columns) and stomach tidal volumes (grey columns) for a given self-inflatable bag size and LESP are superimposed on each other; mask tidal volumes (white columns) start from 0. Wenzel 2001 Critical Care pearls for patients with Pleural Disease Ultrasound is best tool to assess for pleural effusion and PTX (assess lung point However, US limited in chronic lung disease (prior pleurodesis, bullous emphysema, etc) and importance of cross-sectional imaging prior to CT insertion 100cc!! - Effusion needs diagnostic investigation especially if there is concern for infection or bleeding Feller-Kopman NEJM 2018 9
Critical Care pearls for patients with Pleural Disease Take a Timeout if you see a hydropneumothorax post thoracentesis in the ED Secondary to 2 common phenomenon: Pneumothorax Ex Vacuo- phenomenon occurs if underlying lung is unable to expand secondary to bronchial obstruction Trapped lung- inability of lung to expand due to restricting fibrous visceral pleural peel Neither will resolve with chest tube placement Heidecker Chest 2006 Doelken Semin Resp Crit Care Med 2001 Albores NEJM 2015 Trapped Lung Albores J, Wang T. N Engl J Med 2015;372:e25. 10
Questions Reference Budev MM, Arroliga AC, et al. Cor pulmonale: an overview. Semin Respir Crit Care Med. 2003;24(3):233. Klinger JR. Group III Pulmonary Hypertension: Pulmonary Hypertension Associated with Lung Disease: Epidemiology, Pathophysiology, and Treatments. Cardiol Clin. 2016 Aug;34(3):413-33. Fuller BM, Ferguson IT, et al. Lung-Protective Ventilation Initiated in the Emergency Department (LOV-ED): A Quasi-Experimental, Before-After Trial. Ann Emerg Med 2017 Sep;70(3):406-418. Frat JP, Ragot S, et al. Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy. Crit Care Med 2018 Feb;46(2):208-215. Woods JA, Wheeler J, et al. Corticosteroids in the treatment of acute exacerbations of chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2014 Sept; 421 430. Aleva FE, Voets JL, et al. Prevalence and Localization of Pulmonary Embolism in Unexplained Acute Exacerbations of COPD. Chest 2017 March;151(3):544-554. Leuppi JD, Schuetz P, et al. Short-term vs conventional glucocorticoid therapy in acute exacerbations of chronic obstructive pulmonary disease: the REDUCE trial. JAMA. 2013;309:2223-2231. Marini J. Dynamic Hyperinflation and Auto Positive End-Expiratory Pressure Lessons Learned over 30 Years. AJRCC 2011 October;184(7):756-62. Wenzel V, Idris A, et al. The respiratory system during resuscitation: a review of the history, risk of infection during assisted ventilation, respiratory mechanics, and ventilation strategies for patients with an unprotected airway Resus 2001 49;123-134. Feller-Kopman D, Light R. Pleural Disease NEJM 2018 ; 378:740-751. Heidecker J, Huggins JT, et al. Pathophysiology of pneumothorax following ultrasound-guided thoracentesis. Chest 2006;130:173-84. Albores J, Wang T. Trapped Lung NEJM 2015; 372:e25. Doelken P, Sahn SA. Trapped Lung Semin Respir Crit Care Med 2001; 22:631-36. 11