Simulation 04: 28 Year-Old Male in Respiratory Distress (Asthma)

Transcription

1 Simulation 04: 28 Year-Old Male in Respiratory Distress (Asthma) Flow Chart Opening Scenario 28 year-old man in respiratory distress - assess Section 1 Type: IG Anxious pt with asthma history; insp + exp wheezing; SpO2 = 88% (air); tachypnea/tachycardia Aerosol Rx + heliox equip Section 7 Type: DM Section 2 Type: DM Section 3 Type: IG Section 4 Type: DM Section 5 Type: DM Pt started on 4 L/min nasal O2; ABG on air = resp alkalosis + hypoxemia; recommend up to 3 albuterol Rx After 3 albuterol Rx pt lethargic; high HR+RR persist; SpO2 89% 4 L/min O2; breath sounds; ABG = resp acidosis + hypoxemia Recommend continuous albuterol nebulization and IV steroids Select between high volume, continuous medication nebulizer powered by 50% O2 or 70/30 heliox Section 6 Type: DM End Determine albuterol and solute volume for continuous nebulization according to prescription

2 Opening Scenario (Links to Section 1) You are the respiratory therapist in a 500-bed suburban hospital. At 8:30 PM you are called to the Emergency Department to assist in the management of a 28 year-old male with severe shortness of breath brought to the ED by his roommate. (Click the Start button when ready to begin) 2

3 Information-Gathering Section Simulation Section #: 1 Links from: Opening Scenario Links to Section #(s): 2 The patient appears in moderate to severe distress, and is unable to speak in complete sentences. Which of the following would you initially evaluate? (SELECT AS MANY as you consider indicated, then click the Go to Next Section button below to proceed) Requested Information Response Data Response Score Vital signs HR=110, RR=32, temp= 37.2 C, BP=125/80 +1 Mental status Anxious but alert +1 Pulse oximetry 88% on room air +1 CBC Pending +1 Medical history Asthma x 10 yrs with several prior +1 hospitalizations; roommate states patient has had head cold for past week and that his "puffer" ran out 3 days ago Peak expiratory flow Unable to perform +1 Gag reflex Not done Breath sounds Severe inspiratory and expiratory polyphonic +2 wheezing Arterial blood gas Pending +1 Bronchial provocation test Physician disagrees -2 Perfect Score: 9 Minimum Pass Score: 8 3

4 Decision-Making Section Simulation Section #: 2 Links from Section #: 1 Links to Section #(s): 3 After starting the patient on 4 L/min O2 via nasal cannula, you note an SpO2 of 90%, but otherwise the patient s condition is unchanged. Initial ABG results (room air): ph = 7.51, PCO2 = 31 torr; HCO3 = 24 meq/l, PO2 = 58 torr; SaO2 = 89%. CBC indicates eosinophilia. Which of the following would you recommend to the ED physician at this time? (CHOOSE ONLY ONE unless you are directed to Make another. ) Action/Recommendation Intubating the patient and initiating mechanical ventilation Ventilating with 100% O2 using a bag-valve-mask resuscitator, and auscultating the patient s chest Providing up to 3 successive aerosol treatments with 2.5 mg albuterol and 0.5 mg ipratropium (Atrovent) in 3 ml normal saline via SVN Initiating noninvasive ventilation via nasal mask, IPAP = 20 cm H2O, EPAP = 20 cm H2O, 50% O2 Providing up to 3 successive aerosol treatments with 0.5 mg ipratropium (Atrovent) in 3 ml normal saline via SVN Response to Selection Response Score -2 Done. Physician agrees Link to Section Perfect Score: 2 Minimum Pass Score: 1 4

5 Information-Gathering Section Simulation Section #:3 Links from Section #: 2 Links to Section #(s): 4 After administering 3 successive albuterol treatments over 30 minutes, the ED physician asks you to re-assess the patient and make further recommendations. Which of the following would you evaluate at this time? (SELECT AS MANY as you consider indicated, then click the Go to Next Section button below to proceed) Requested Information Response Data Response Score Vital signs (HR +RR) HR=122/min, RR=36/min +1 Skin color Dusky with slightly cyanotic lips +1 Mental status Lethargic but arousable +1 Pulse oximetry 89% on 4 L/min nasal cannula +1 Complete blood count (CBC) Not done Sputum sample Not done Bedside spirometry (FEV) Not done -2 Breath sounds Breath sounds markedly decreased throughout +1 both lung fields; wheezing persists Repeat arterial blood gas ph = 7.30, PCO2 = 51 torr, HCO3 = meq/l, PO2 = 58 torr, SaO2 = 88% Chest X-ray Hemidiaphragms low and flat; hyperlucency +1 with some increased bronchial wall markings in lung fields Perfect Score: 7 Minimum Pass Score: 5 5

6 Decision-Making Section Simulation Section #:4 Links from Section #: 3 Links to Section #(s): 5 Based on your current assessment of the patient, what additional therapy would you recommend be instituted? (CHOOSE ONLY ONE unless you are directed to Make another. ) Action/Recommendation Providing continuous albuterol nebulization and IV methylprednisolone (Solu-Medrol) Switching the patient to a nonrebreathing mask at 10 L/min and monitoring closely Intubating the patient and initiating mechanical ventilation VT = 8 ml/kg, 60% O2 Initiating noninvasive ventilation via nasal mask, IPAP = 20 cm H2O, EPAP = 20 cm H2O, 50% O2 Providing up to 3 additional aerosol treatments with 0.5 mg ipratropium (Atrovent) in 3 ml normal saline via SVN Response Link to Response to Selection Score Section Physician agrees; therapy initiated Perfect Score: 2 Minimum Pass Score: 1 6

7 Decision-Making Section Simulation Section #: 5 Links from Section #: 4 Links to Section #(s): 6,7 Which of the following approaches would you select to administer the continuous albuterol therapy? (CHOOSE ONLY ONE unless you are directed to Make another. ) Action/Recommendation A high volume, continuous medication nebulizer (e.g., HEART, Flo-Mist) powered by 50% O2 A standard large volume allpurpose nebulizer powered by 80% He/20% O2 with the air entrainment opening set to 40% A small particle aerosol generator (SPAG) powered by 50% O2 via a blender A high volume, continuous medication nebulizer (e.g., HEART, Flo-Mist) powered by 70% He/30% O2 A standard SVN powered by compressed air Response to Selection Physician agrees; therapy implemented.. Physician agrees; therapy implemented Response Link to Score Section Perfect Score: 2 Minimum Pass Score: +2 7

8 Decision-Making Section Simulation Section #: 7 Links from Section #: 5 Links to Section #(s): 6 The physician agrees to your continuous nebulization of albuterol using a 70% He/30% O2 mixture. Which of the following appliances would you select to deliver the drug aerosol to this patient? (CHOOSE ONLY ONE unless you are directed to Make another. ) Action/Recommendation Connect a high-flow nasal cannula to the medication nebulizer Response to Selection Response Score Link to Section Connect a standard aerosol mask with large bore tubing to the medication nebulizer Connect a nonrebreathing mask with small bore tubing to the medication nebulizer Connect a valved/sealed mask with large bore tubing to the medication nebulizer Connect a face tent with large bore tubing to the medication nebulizer Physician agrees; therapy implemented +1 6 Perfect Score: 1 Minimum Pass Score: 1 8

9 Decision-Making Section Simulation Section #: 6 Links from Section #: 5,6 Links to Section #(s): End The doctor orders continuous albuterol at 15 mg/hr for 3 hours. You have on hand a multidose 30 ml vial of 0.5% albuterol. The nebulizer you select has a capacity of 100 ml and has an output of 20 ml/hour at the recommended flow. Which of the following mixtures would you prepare for nebulization? (CHOOSE ONLY ONE unless you are directed to Make another. ) Action/Recommendation 50 ml normal saline mixed with 10 ml of 0.5% albuterol 30 ml normal saline mixed with 30 ml of 0.5% albuterol 45 ml normal saline mixed with 15 ml of 0.5% albuterol 90 ml normal saline mixed with 10 ml of 0.5% albuterol 80 ml normal saline mixed with 20 ml of 0.5% albuterol Response Link to Response to Selection Score Section Physician agrees. +2 End. in this section in this section -3-2 Perfect Score: +2 Minimum Pass Score: +1 Calculations: 15 mg/hr x 3 hrs = 45 mg albuterol 0.5% albuterol = 5 mg/ml 45 mg 5 mg/ml = 9 ml (required volume of albuterol solution to administer 45 mg) 3 hrs nebulization x 20 ml/hr = 60 ml total volume needed 60 ml 9 ml (albuterol solution) = 51 ml Answer: 51 ml saline + 9 ml 0.5% albuterol (choose closest answer) 9

10 RTBoardReview Simulation Year Old in Respiratory Distress Condition/Diagnosis: Asthma (Severe Exacerbation) Simulation Scoring Individual Response Scoring (Used for All RTBoardReview Simulations) Score Meaning +2 Essential/optimum to identifying or resolving problem +1 Likely helpful in identifying or resolving problem 0 Neither helpful nor harmful in identifying or resolving problem Unnecessary or potentially harmful in identifying or resolving problem -2 Wastes critical time in identifying problem or causes direct harm to patient -3 Results in life-threatening harm to patient Summary Scoring of Simulation 04 Grayed sections are branches off ideal pathway (may be equivalent or corrective) Section IG Max IG Min DM Max DM Min Equivalent DM from Section 5 TOTALS MPL% 81% 63% Cut Score = IG Min + DM Min = = 18 MPL% = Minimum Pass Level as a percent = (Min/Max) x 100 IG and DM MPL% vary by problem; typically ranges are 77-81% for IG and 60-70% for DM If the IG or DM raw score is negative (e.g., -2) then the reported % score = 0 The Cut Score for a problem is the sum of IG Min + DM min To pass a problem, the sum of one s IG + DM raw scores must be the Cut Score 10

11 Take-Home Points RTBoardReview Simulation Year Old Male in Respiratory Distress Condition/Diagnosis: Asthma (Severe Exacerbation) Asthma is a chronic inflammatory disorder of the airways that often begins in childhood and may be associated with a family history of the disease. An IgE-mediated response to certain allergens (atopy) is the most common predisposing factor, with viral infections being an important cause of exacerbations. Pathologically, it is characterized by airway infiltration of inflammatory cells (neutrophils, eosinophils), mast cell activation and epithelial cell injury, with the resulting inflammation causing airway hyperresponsiveness and airflow obstruction. Key pointers in the assessment and treatment of patients with asthma suffering an acute exacerbation requiring emergency treatment include the following: Assessment/Information Gathering Initial assessment should include a brief history, brief physical exam and objective measures of lung function (if obtainable - not indicated in severe or life-threatening exacerbations) The initial history should include 1) time of onset and likely causes of current exacerbation; 2) severity of symptoms, and response to any treatment given before admission to ED; 3) all current medications and time of last dose; 4) estimate of number of previous ED visits and hospitalizations; and 5) other potentially complicating illness, especially pulmonary or cardiac disorders The initial physical exam should assess 1) the severity of the exacerbation; 2) overall patient status, e.g., level of alertness, presence of cyanosis, respiratory distress, and wheezing (see following table). Note that severe obstruction may be accompanied by a 'silent chest'. Assessment Severity Moderate Severe Life-Threatening Breathlessness Dyspnea at rest; talks in phrases Dyspnea at rest; talks in words Limited effort indicating fatigue Sensorium/behavior Alert/may be agitated Alert/usually agitated Drowsy or confused Respiratory rate Tachypnea Tachypnea Bradypnea possible Work of breathing/ respiratory distress May show accessory muscle use with Usually shows accessory muscle use May exhibit thoracoabdominal paradox retractions with retractions Heart rate/pulse Tachycardia with Tachycardia with pulsus Bradycardia pulsus paradoxus paradoxus Breath sounds Prominent expiratory Prominent inspiratory + wheezing expiratory wheezes FEV 1 or PF (% pred) 40% < 40% (if able) < 25% (if able) PaO 2/SaO 2 (air) 60 torr/90% < 60 torr/90% < 60 torr/90% PaCO 2/pH < torr/ ph >40 torr/n or ph >45-50 torr/ ph (indicating fatigue) Absence of wheezing ( silent chest ) Pulse oximetry is indicated for any patient who is in severe distress; serial measurements are useful in assessing both the severity of the exacerbation and improvement with treatment Laboratory studies may be helpful, but they are not required for most patients, and they should not delay initiation treatment 11

12 CBC is not required routinely but may be useful in patients who have fever or purulent sputum Consider ABGs for evaluating PaCO2 levels in patients who have suspected hypoventilation, severe distress, or those with a FEV1 or PEF < 25 percent of predicted after initial treatment (note that respiratory alkalosis is common early in an attack, so a 'normal' PCO2 of torr may indicate worsening hypoventilation and an increased risk of respiratory failure) Chest radiography is not essential for routine assessment but should be obtained for patients suspected of a complicating cardiopulmonary process, such as congestive heart failure, pneumothorax, pneumonia, or lobar atelectasis. An ECG is not required routinely, but a baseline ECG may be appropriate in patients older than 50 years of age and in those who have coexistent heart disease or COPD pulmonary Differential diagnosis includes upper airway obstruction due to foreign body aspiration, hematomas, infection (e.g., epiglottitis), vocal cord dysfunction, tracheal narrowing or COPD Treatment/Decision-Making Treatment should begin immediately following recognition of a moderate, severe, or lifethreatening exacerbation Initial treatment should include: o O2 therapy to maintain SpO2 90% (monitor until a good bronchodilator response occurs) o Short-acting beta agonist (SABA) aerosol therapy, e.g., albuterol Repeat SABA treatments every minutes (x3) as needed Combine ipratropium bromide with the SABA for severe exacerbations Consider continuous SABA administration for severe exacerbations o Systemic corticosteroids to decrease airway inflammation Consider adjunct treatments such as heliox and/or IV magnesium sulfate for severe exacerbations unresponsive to these initial treatments (may decrease need for intubation) Do not recommend methylxanthines, antibiotics (except as needed for comorbid conditions), chest physical therapy, mucolytics, or sedation In the conscious and cooperative patient whose PaCO2 is rising (> torr), a trial of noninvasive positive pressure ventilation (NPPV) may prevent further deterioration If the patient already has progressed to life-threatening respiratory failure (ph < 7.25), application of NPPV may only delay needed intubation and invasive support Ventilator management of severe asthma involves low volumes (plateau pressures 30 cm H2O) and long expiratory times; use of extrinsic applied PEEP is not required; in the worst cases hypercapnia is allowed as long as the ph remains above 7.25; permissive hypercapnia may require heavy sedation. 12

13 Follow-up Resources Standard Text Resources: Des Jardins, T., & Burton, G.G. (2011). Asthma (Chapter 12). In Clinical Manifestations and Assessment of Respiratory Disease, 6th Ed. Maryland Heights, MO: Mosby-Elsevier. Wilkins, R.L., & Gold, P.M. (2007). Asthma. (Chapter 3). In Wilkins, R.L., Dexter, J.R., & Gold, P.M. (Eds). Respiratory Disease: A Case Study Approach to Patient Care. 3rd Edition. Philadelphia: F.A. Davis Useful Web Links: National Heart Lung & Blood Institute (2007). Expert Panel Report 3 (EPR): Guidelines for the Diagnosis & Management of Asthma. Section 5: Managing Exacerbations of Asthma. Bethesda. MD: US Department of Health and Human Services. Lugogo, NL, & MacIntyre, NR. (2008). Life-threatening asthma: Pathophysiology and management. Respir Care, 53, Brenner, BE. Asthma. E-Medicine/Medscape. overview Peters, SG. (2007). Continuous bronchodilator therapy. Chest, 131, Kim, IK, Saville, AL, Sikes, KL, & Corcoran, TE. (2006). Heliox-driven albuterol nebulization for asthma exacerbations: an overview. Respir Care, 51, Medoff, BD. (2008). Invasive and noninvasive ventilation in patients with asthma. Respir Care, 53, Oddo, M, Feihl, F, Schaller, M, & Perret, C. (2006). Management of mechanical ventilation in acute severe asthma: Practical aspects. Intensive Care Med, 32, acute%20severe%20asthma%20(Oct6-08).pdf Stather, DR, & Stewart, TE. (2005). Clinical review: Mechanical ventilation in severe asthma. Critical Care, 9,