Asthma

1. Asthma A Chronic disease of the airways that may cause: • Wheezing • Breathlessness • Chest tightness • Nighttime or early morning coughing

3. The bronchospasm characteristic of the acute asthmatic attack is typically reversible. (برونکواسپاسم که با درمان بهبود یابد کاراکتریک حمله آسم حاد است) It improves spontaneously or within minutes to hours of treatment

4. Asthma can exist by itself or coexist with: • chronic bronchitis, or • emphysema, or • bronchiectasis

5. Symptoms/Chief Complaint • Progressive dyspnea • Cough • Chest tightness • Wheezing/coughing

6. The rapidly reversible airflow obstruction of asthma is mainly due to bronchial smooth muscle contraction

7. Focus of Therapy • Pharmacologic manipulation of airway smooth muscle • Do not overlook physiologic impairment caused by mucous production and mucosal edema • Bronchospasm can be reversed in minutes • Airflow obstruction due to mucous plugging and inflammatory changes in bronchial walls may not resolve for days/weeks - • may lead to atelectasis, infectious bronchitis, pneumonitis

8. Asthma Triggers • Immunologic reaction • Viral respiratory/sinus infections • change in temperature/humidity • Drugs/Chemicals - • aspirin, NSAIDS • Exercise • GE Reflux • Laughing/coughing • Environmental factors - • strong odors, pollutants, dust, fumes

9. Patient Exam • Wheezing • may be audible w/o stethoscope • ویز در آسم معمولا بازدمی است (بازدم طولانی تر است) • شدت ویز با شدت آسم ارتباطی ندارد • Use of accessory muscles of inspiration • (رتراکسیون بین دنده ای و ...) • diaphragmatic fatigue • Paradoxical respirations • (شکم و قفسه سینه عکس هم حرکت میکنند) • خستگی عضلات تنفسی و احتمال آپنه تنفسی • Reflect impending ventilatory failure • Altered mental status - • lethargy, exhaustion, agitation, confusion

10. Patient Exam • Hyperrsonance to percussion • decreased intensity of breath sounds • prolongation of expiratory phase w or w/o wheezing • The intensity of the wheeze may not correlate with the severity of airflow obstruction • “quiet chest” - very severe airflow obstruction

11. Risk factors for death from asthma: • Past history of sudden severe exacerbations  • Prior intubation for asthma  • Prior admission for asthma to an intensive care unit   • Two or more hospitalizations for asthma in the past year  • Three or more emergency care visits for asthma in the past year   • Hospitalization or emergency care visit for asthma within the past month • Use of more than two canisters per month of inhaled short-acting 2-agonist • Current use of systemic corticosteroids or recent withdrawal from systemic corticosteroids  • Difficulty perceiving airflow obstruction or its severity  • Comorbidity, as from cardiovascular diseases or chronic obstructive pulmonary disease  • Serious psychiatric illness or psychosocial problems  • Low socioeconomic status in urban residents   • Illicit drug use

12. Asthma Treatment • Nebulized B-adrenergic drugs • Corticosteroids • Nebulized anticholinergics • Magnesium sulfate • Oxygen • Long acting beta-agonists • Inhaled steroids

13. Managing Asthma: Indications of a severe attack: • Breathless at rest(تنگی نفس در استراحت) • hunched forward(روی تخت خم شود) • talking in words rather than sentences(استفاده از کلمات بریده) • Agitated • (Peak flow rate) PFR< 60% of normal in Spirometry

14. Treatment Goals of Severe Asthma • Improve airway function rapidly • Avoid hypoxemia • Prevent respiratory failure and death

15. Symptoms Mild Moderate Severe Breathlessness walking talking at rest  Position Can lie down Prefers sitting upright   Talks inSentences Phrases Words Alertness May be agitated Usually agitated Usually agitated Classifying Severity of Asthma Exacerbations

16. Classifying Severity of Asthma Exacerbations Signs Mild Moderate Severe نکته: اختلاف فشارخون بین دم و بازدم بیمار = Pulsus Paradoxus

17. Classifying Severity of Asthma Exacerbations Functional assessmentMild Moderate Severe نکته: در اورژانس پالس اکسیمتری موجود است که میتوانیم بر اساس آن آسم را طبقه بندی کنیم

18. Respiratory Arrest Imminent • Drowsy or confused • Paradoxical thoracoabdominal movement • Absent Wheeze • Bradycardia • Absence Pulsus paradoxus suggests respiratory muscle fatigue 

19. Asthma Mimickersتشخیص افتراقی های آسم)) • Congestive heart failure ("cardiac asthma") • Upper airway obstruction • Aspiration of foreign body or gastric acid • Bronchogenic carcinoma with endobronchial obstruction • Metastatic carcinoma with lymphangitic metastasis • Sarcoidosis with endobronchial obstruction • Vocal cord dysfunction • Multiple pulmonary emboli (rare)

20. treatment of acute asthma Goal in the ED • reverse airflow obstruction rapidly by repetitive or continuous administration of inhaled 2-agonists • ensure adequate oxygenation • relieve inflammation

21. Initial Assessment • History • physical examination (auscultation use of accessory muscles, heart rate, respiratory rate) • PEFR or FEV • oxygen saturation • other tests as indicated

22. Diagnosis • Bedside spirometry • rapid, objective assessment ,guide to the effectiveness of therapy. • The forced expiratory volume in 1 s (FEV1) • peak expiratory flow rate (PEFR) • Sequential measurements • management decisions

23. Pulse oximetry • assessing oxygenation and monitoring oxygen saturation during treatment. • ABG is not indicated in most patients with mild to moderate asthma exacerbation (در همه بیماران آسمی ABG نیاز نیست مگر اینکه بخواهیم سطح PCO2را بدانیم)

24. ABG assess for hypoventilation with carbon dioxide retention and respiratory acidosis • clinical evidence of severe attacks • PEFR or FEV1 of less than 25 percent predicted • With acute attacks, ventilation is stimulated, resulting in a decrease in partial pressure of carbon dioxide (PaCO2) • normal or slightly elevated PaCO2 (e.g., 42 mm Hg) indicates extreme airway obstruction and fatigue and may herald the onset of acute ventilatory failure

25. Radiography CXR) کمک کننده نیست مگر برای پیداکردن تریگر و تشخیص افتراقی ها) • clinical indication of a complication • pneumothorax, pneumomediastinum, pneumonia, or other medical concern • one-third of asthma exacerbations requiring admission, will demonstrate an abnormality on chest radiograph

26. CBC اندیکاسیون ندارد • modest leukocytosis secondary to administration of: B -agonist therapy or corticosteroid treatment • In patients taking theophylline before ED presentation, a serum theophylline level بیماری که تئوفیلین میگرفته سطح تئوفیلین چک شود

27. ECG (EKG در بیمارانی که بیماری زمینه ای قلبی دارند میگیریم زیرا به طور روتین تغییرات غیر اختصاصی دیده میشوند که بادرمان آسم رفع میگردند) • Routine electrocardiogram is unnecessary which resolve with treatment: • right ventricular strain, or • abnormal P waves, or • nonspecific ST- and T-wave abnormalities Older patients, especially those with coexisting heart disease, should have cardiac monitoring during treatment

28. Impending or Actual Respiratory Arrest • Intubation and mechanical ventilation with 100% 02 • Nebulized B2 agonist and anticholinergic • Intravenous steroid • Admit to ICU

29. درمان بر اساس FEV1 یا PEFR • FEV1 or PEFR <50% • (Severe Exacerbation) • اکسیژن تا رساندن 90%≤So2 • استنشاق دوز زیاد ß2-agonist و آنتی کولینرژیک با نبولایزر هر 20دقیقه یا مداوم برای مدت یک ساعت. • استرویید خوراکی • FEV1 or PEFR >50% • اکسیژن تا رساندن 90%≤So2 • استنشاق ß2-agonist تا 3 بار در ساعت اول • استرویید خوراکی (اگر درمانهای بالا فورا جواب نداد یا اخیرا داروی استرویید خوراکی مصرف میکرده است) نکته: چون نبولایزر بتا 2 آگونیست (سالبوتامول) نداریم , از اسپری سالبوتامول 8 پاف هر 20 دقیقه میدهیم تا 3 بار و سپس ارزیابی مجدد

30. Repeat Assessment • Symptoms. • physical examination. • PEFR. • 02 saturation. • other test as needed

31. Severe Exacerbation

32. Moderate Exacerbation

33. Incomplete Response

34. Good Response

35. Discharge Home

36. Poor Response

37. Poor Response

38. Poor Response

39. medications are used in the treatment of acute asthma • adrenergic agonists • anticholinergics • glucocorticoids • Magnesium, heliox (mixture of helium and oxygen), and ketamine may be considered when the aforementioned medications fail to relieve bronchospasm. • Mast cell-stabilizing agents, methylxanthines, and leukotriene modifiers are currently reserved for maintenance therapy only

40. Adrenergic Agents • Adrenergic receptors • Stimulation of B 1-receptors increases rate and force of cardiac contraction and decreases small intestine motility and tone • B2-adrenergic stimulation promotes bronchodilation, vasodilation, uterine relaxation, and skeletal muscle tremor

41. Adrenergic Agents • stimulation of the enzyme adenyl cyclase, which converts intracellular adenosine triphosphate into cyclic adenosine monophosphate • enhances the binding of intracellular calcium to cell membranes, reducing the myoplasmic calcium concentration, and results in relaxation of bronchial smooth muscle • inhibit mediator release and promote mucociliary clearance.

42. side effect of B-adrenergic drugs: • skeletal muscle tremor (most common) • nervousness, anxiety, • insomnia, headache, • hyperglycemia, • palpitations, tachycardia, and hypertension • potential cardiotoxicity(combination with theophylline not significant problems) • Arrhythmias and evidence of myocardial ischemia(rare)

43. Inhaled short-acting B-2 agonists Albuterol •  Nebulizer solution (5 mg/mL) • 2.5–5.0 mg every 20 min for 3 doses • then 2.5–10 mg every 1–4 h as needed or 10–15 mg per h continuously • Only selective B-2 agonists are recommended • for optimal delivery, dilute aerosols to minimum of 4 mL at gas flow of 6–8 L per min

44. Albuterol •  (MDI) Meter Dose Inhalation (90μ/puff) • 4–8 puffs every 20 min up to 4 h • then every 1–4 h as needed • As effective as nebulized therapy if patient is able to coordinate inhalation maneuver; use spacer/holding chamber

45. Inhaled short-acting B-2 agonists •  Bitolterol  •  Nebulizer solution (2 mg/mL)   •   MDI (370 macg/puff)      • Pirbuterol • MDI (200 g/puff)

46. Inhaled short-acting B-2 agonists • Systemic (injected), B-2 agonists • Epinephrine (1:1000 or 1 mg/mL) • 0.3–0.5 mg SC every 20 min for 3 doses • Terbutaline (1 mg/mL) • 0.25 mg SC every 20 min for 3 doses No proven advantage of systemic therapy over aerosol

47. Anticholinergics • potent bronchodilators in patients with asthma and other forms of obstructive lung disease • anticholinergics affect large, central airways, • whereas B-adrenergic drugs dilate smaller airways • competitively antagonize acetylcholine at the postganglionic junction between the parasympathetic nerve terminal and effector cell • blocks the bronchoconstriction induced by vagal cholinergic-mediated innervation to the larger central airways • concentrations of cyclic guanosine monophosphate in airway smooth muscle are reduced,further promotin bronchodilation

48. Anticholinergics Ipratropium bromide •  Nebulizer solution (0.2 mg/mL) • 0.5 mg every 30 min for 3 doses • then every 2–4 h as needed • Should not be used as first-line therapy; • should be added to 2 agonist therapy; • may mix in same nebulizer with albuterol • MDI (18 g/puff) • 4–8 puffs every 6–8 h

49. side effects • dry mouth • Thirst • difficulty swallowing • Less commonly • tachycardia, restlessness, irritability, confusion, difficulty in micturition, ileus, blurring of vision, or an increase in intraocular pressure

50. Corticosteroids • highly effective drugs in asthma exacerbation • one of the cornerstones of treatment • mechanism of action is unknown(مکانیسم فعالیت نامشخص است) • Restoring B-adrenergic responsiveness • reducing inflammation • The onset of anti-inflammatory effect is delayed at least 4 to 8 h after intravenous or oral administration. 4) تا 8 ساعت بعد از مصرف خوراکی یا وریدی, اثرات آن شروع میشود)