Presentation on theme: "Management of Severe Obstructive Lung Disease"— Presentation transcript:
1 Management of Severe Obstructive Lung Disease Craig Rackley, MDAssistant Professor of MedicineDuke University Medical Center
2 Faculty Disclosures None Faculty notes: Please list on this slide any potential conflicts of interest (COI) you reported to the ACCP when agreeing to speak for this course or any new, previously not disclosed, potential COIs that you have .ORSimply type in “no potential conflicts of interest to disclose.”
3 Objectives Understand the anatomy of COPD Understand GOLD classification of COPDUnderstand basic pharmacologic treatment targets and goalsUnderstand when to use non-invasive ventilation for acute exacerbations of COPD/AsthmaUnderstand how to manage a patient with COPD or asthma requiring invasive ventilation
4 Clinical case69 yo man with a 90 pk-yr smoking history, FEV1/FVC ratio of .48 and an FEV1 of 26% predicted comes in for an initial evaluation in pulmonary clinic.
6 Causes of Airflow Obstruction Increased resistance and narrowing of airways due toAirway smooth muscle hypertrophy and contractionMucous cell hypertrophy, increased mucous production and impactionAirway inflammationAirway fibrosisExternal compression from hyper-inflated alveoli
8 Treatment goalsDecrease resistance and narrowing of airways by reversingAirway smooth muscle hypertrophy and contractionInhaled beta agonists, anticholinergics, Magnesium, theophyllineMucous cell hypertrophy, mucous production and impactionInhaled anticholinergics, corticosteroidsAirway inflammationCorticosteroids, antibiotics if indicatedAirway fibrosisIrreversibleExternal compression from hyper-inflated alveoliAllow for effective exhalation
11 GOLD classification of severity of airflow limitation in COPD Global Initiative for Chronic Obstructive Lung Disease
12 Combined Assessment of COPD FEV1≥50%FEV1<50%Global Initiative for Chronic Obstructive Lung Disease
13 Clinical case cont.He had an FEV1/FVC ratio of .48 and an FEV1 of 26% predicted. He had 2 exacerbations last year, one required hospitalization, and he is short of breath with minimal activity. He is on no medications other than prn albuterol, which he uses 5+ times/day..
14 GOLD recommended first choice therapy Global Initiative for Chronic Obstructive Lung Disease
15 Clinical case cont.Patient is started on an ICS + LABA and a LAMA with recommendation to use albuterol as needed. He has a walk in clinic that demonstrates he needs 2 LPM oxygen via nasal cannula with exertion, he is given appropriate immunizations, and he is referred to pulmonary rehab.
16 Clinic template Chronic Obstructive Pulmonary Disease: Based on the Global Initiative for Chronic Obstructive Lung Disease Combined Assessment of COPD, the patient is in risk category:A: FEV1 >/= 50% and </=1 exacerbation/yr and minimal/no symptoms or dyspneaB: FEV1 >/= 50% and </=1 exacerbation/yr and moderate/severe symptoms or dyspneaC: FEV1 <50% or >1 exacerbation/yr and minimal/no symptoms or dyspneaD: FEV1 <50% or >1 exacerbation/yr and moderate/severe symptoms or dyspneaRecommendation:-Tobacco dependence:-No longer smoking. Encouraged continued abstinence.-Currently smoking. Extensively discussed need for smoking cessation. Provided information on Quit Now. Offered nicotine replacement and pharmacotherapy. We will ***-Pulmonary rehab/exercise:-Patient currently in rehab or exercising regularly. Encouraged continued lifelong exercise.-Patient currently not exercising adequately. We discussed options for exercise and pulmonary rehab. We will ***-Oxygen:-Patient has an oxygen sat >/=88% on RA at rest and with walking. Therefore, supplemental oxygen is not indicated.-Patient has an oxygen sat <88% on RA at rest and/or with walking. Therefore, supplemental oxygen is required at *** LPM at rest, *** LPM with sleep, and *** LPM with exertion.-Pharmacotherapy:-GOLD A: Short acting bronchodilator as needed-GOLD B: Long acting bronchodilator-GOLD C: ICS + long acting bronchodilator-GOLD D: ICS + long acting beta agonist and/or long acting anticholinergic
17 Clinical case cont.He does well over the next 6 months until he gets an upper respiratory infection. This leads to significant increase in his shortness of breath and cough. His symptoms progress to where he is so short of breath he calls EMS and is taken to the ED.
18 Clinical case cont.On initial evaluation he has a temp of 38.2 C, HR of 108, BP of 95/60, RR of 26, and O2 sat on RA of 87%. He is alert and oriented, but speaking in 2-3 word sentences. He is using accessory muscles to breath and has very poor air movement.ABG on RA:pH: 7.30pCO2: 64pO2: 53
19 When to consider ventilatory support Evidence of respiratory muscle fatigue (clinical work of breathing, serum lactate)HypercarbiaRespiratory acidosis
20 What is the “best” way to provide ventilatory support?
21 NIV reduces need for intubation in COPD exacerbations Cochrane Database Syst Rev. 2004;(3):CD
25 How to initiate NPPVInitiate with oronasal facemask. If patients cannot tolerate then consider full face mask.Settings are adjusted toAchieve adequate oxygenationReduce work of breathingMaintain “adequate” pHProvide tolerable pressure that does not lead to worsened hyperinflationMaximize patient-ventilator synchrony
26 Clinical case cont. ABG on RA: pH: 7.22 pCO2: 74 pO2: 65 The patient is placed on bipap 12/5 and 40% FiO2. His RR decreased to 20 and his work of breathing improved. However, over the next several hours his work of breathing increased, and he became less alert despite adjustments to his bipap settings. A repeat ABG was sent.ABG on RA:pH: 7.22pCO2: 74pO2: 65
27 Indications for intubation Respiratory arrestAltered level of consciousnessExtreme exhaustionInability to adequately ventilate with NPPV
32 How to initiate mechanical ventilation Respiratory rate: adjusted to a rate that allows expiratory flow to reach zero prior to next breathTidal Volume: approximately 6-8 cc/Kg ideal body weightInspiratory time(PAC): adjusted to allow for adequate volume and to continue delivering breath with patient effort (i.e. inspiratory flow does not stop while patient is still wanting more air.)Inspiratory flow rate(VAC): adjusted to give adequate flow and allow for adequate exhalation (I:E ratio)PEEP: adjusted to the lowest level needed to ensure patient is able to trigger all breathsPlateau pressure: <30 cm H2OAppropriate level of sedation is key to ensure adequate patient-ventilator synchrony
33 Clinical case cont.He is sedated, paralyzed, and placed on mechanical ventilation: VAC with a Vt of 6 cc/kg, RR of 24, PEEP of 5, and an FiO2 of 40 %. After 20 min his HR is 120, BP is 80/45, and his sat is 90%. You send a stat ABG.ABG:pH: 7.18pCO2: 82pO2: 58
37 Consequences of hyperinflation or air trapping Barotrauma/volutraumaDecreased venous return, preload, and cardiac output
38 How to reduce hyperinflation or air trapping Reduce respiratory rateReduce tidal volumeIncrease expiratory timeIncrease inspiratory flow rate (VAC)Decrease inspiratory time (PAC)Tolerate increased PCO2
39 Clinical case cont.The patient’s RR is decreased to 16. His new settings are VAC with a Vt of 6 cc/kg, RR of 16, PEEP of 5, and an FiO2 of 40 %. After 30 min his HR is 80, BP is 110/65, and his sat is 98%. You send a repeat ABG.ABG:pH: 7.32pCO2: 56pO2: 84
40 Our patient after the vent changes PressureFlowVolumeTime
41 Clinical case cont.He remains stable overnight, so the paralytics are discontinued and his sedation is lightened. When you come back the next morning he is awake, alert, and following commands, but just doesn’t quite look comfortable.
43 Information from an end expiratory pause “Clamp” circuitPEEPi = 10Flow (L/s)Airway pressure (cm H2O)Volume (L)
44 Intrinsic PEEP is end expiratory alveolar pressure
45 PEEP can be increased until all patient efforts trigger the ventilator in assisted modes Hyperinflation will lead to increased Pplat in VAC or reduced tidal volumes with PAC
46 Why not increase extrinsic PEEP to match intrinsic PEEP?
47 Regional effects of positive pressure ventilation in obstructive lung disease Regional over-distention can lead to worsened V/Q matching, increased dead space ventilation, and increased lung injury.
48 Clinical case cont.His PEEP is increased to 8 cm H2O, and he is successfully triggering all breaths. Over the next 24 hours his sedation is further reduced, and the next morning he passes an SBT, but at the end of 30 min he appears to have a slight increase in his work of breathing. He is alert, cooperative and following all commands. What do you do??
50 Clinical case cont.He is extubated directly to bipap, does well for 6 hours, and is successfully weaned from bipap with improved work of breathing. He transfers out of the ICU the next morning.
51 SummaryAirflow obstruction has multiple components that should be adequately treated pharmacologicallyNPPV reduced mortality and reduces need for intubation in patients with COPD exacerbationsUnderstanding intrinsic PEEP and allowing for adequate exhalation are key to mechanical ventilation in obstructive lung diseaseExtubation to NIV may reduce risk of re-intubation
52 Questions?PowerPoint tip: End your presentation with a simple question slide to:Invite your audience to ask questions.Provide a visual aid during question period.Avoid ending a presentation abruptly.
53 Information from an end inspiratory pause Peak and Plateau similarLarge difference between Peak and PlateauFlow stops prior to next breathFlow does not reach zero prior to next breathInhaled volume = exhaled volumeInhaled volume > exhaled volumeNo obstructionObstruction