Acute Breathlessness

Important Causes

1. Bronchial asthma - acute exacerbation
2. COPD - acute exacerbation
3. Cardiogenic pulmonary edema
4. Severe respiratory infection like pneumonia, bronchopneumonia
5. Pneumothorax
6. Pulmonary embolism
7. Upper airway obstruction by foreign body, tumor
8. Rapidly accumulating pleural effusion or hemothorax
9. Adult respiratory distress syndrome (non-cardiopulmonary edema)
10. Acute allergic alveolitis
11. Rapidly accumulating Pericardial effusion
12. Exclude tachypnoea due to other causes like—metabolic acidosis, hyperventilation due to anxiety.

Approach to a Patient with Acute Breathlessness

• Put the patient in propped up position, and re-assure
• Give oxygen inhalation when required (Bronchial asthma/ COPD/Pulmonary edema)
• Check pulse, blood pressure, respiratory rate, JVP, look for cyanosis
• Short relevant history and quick physical examination for the cause of breathlessness
• Fever and/or yellow sputum always suggest the presence of respiratory infection— as the only cause for breathlessness or cause for exacerbation of another potential cause
• Specific management according to the cause of breathlessness should be instituted without any delay.
• Physical Examination in Acute Asthma
• Respiratory rate, pulse, temperature, blood pressure (respiratory rate >32/mt, pulse rate >120/mt with pulsus paradoxus of >15 mm Hg with profuse sweating, apprehension, restlessness and inability to talk indicates a severe attack (Acute severe asthma)
• Presence of cyanosis, absence of breath sounds on auscultation indicate a more severe state
• Mild to moderate hypertension detected during an attack usually is reactive and subsides when the attack is controlled
• Fever and/or yellow sputum or even an increase in quantity of sputum indicates infection and requires antibiotics.
• Always look for pneumothorax, collapse or consolidation as the cause of acute exacerbation.
• All these can be missed by a casual physical examination since physical findings are subtle in the presence of grossly inflated lungs.
• Hence X-ray chest is indicated, when asthma is very severe and not improving or when we think that the expected findings in the X-ray will change the management (like pneumothorax, effusion, collapse).
• In any one with an apparent asthma-like attack, especially when there is no past history of breathlessness, consider the possibility of pulmonary edema, upper airway obstruction and mild pulmonary embolism.
• Presence of stridor always suggests upper airway obstruction. But classical stridor occurs only in obstruction at the level of larynx. In upper airway obstruction below that level one gets inspiratory rhonchi more than expiratory rhonchi.
• Confusions in differentiating asthma from upper airway obstruction can occur as the following case history illustrates

Management of Acute Asthma

Identify precipitating factors like

• Recent respiratory infection (upper respiratory/lower respiratory)
• Exposure to dust/pollen/other inhaled or ingested chemicals
• Emotional stress
• Change of drugs or stoppage of medicines for asthma
• Change of occupation, residence, place of work
• Drug induced - ingestion of aspirin or beta blockers
• Exercise, exposure to cold weather, cold food

Rarely, the cause of acute exacerbation of asthma can be pulmonary embolism, pneumothorax, pulmonary edema due to IHD or mitral stenosis

Guidelines for Treatment of Acute Severe Asthma

(Only adult doses are mentioned)

• Start oxygen inhalation
• Start an IV line, preferably with dextrose, if not contraindicated.
• Give Inj. Aminophylline 250 mg dissolved in 20 ml of 5% dextrose slow IV (Caution in patients taking theophylline preparation)
• Inj. Salbutamol or terbutaline SC dose 500 micrograms 6-8 hourly (if a nebulizer is available these drugs can be administered with the help of it)
• Ipratropium bromide inhalation (or nebulized) can also be added to the above, if not improving with other measures
• Inj Hyzonate (Hydrocortisone) 200 mg IV stat and 6th hourly. One must be liberal in the use of steroid in acute phase. It takes about 6 hours for its full action to be established, hence preferable to start as early as possible
• Give IV fluids to hydrate the patient, to reduce the viscidity of sputum and to supplement calories to prevent exhaustion of respiratory muscles (severe dyspnea prevents the patient from taking oral feeds. There is excessive loss of fluid through sweating and respiration and increased activity of respiratory muscles lead to exhaustion)
• If the patient is cyanosed it is an indication for ventilatory support. Give sodium bicarbonate 100 ml IV stat (ideally using blood gas analysis). Excess sodium bicarbonate can cause severe metabolic alkalosis on recovery/ ventilator therapy

Avoid Adrenaline in a patient with severe asthma and cyanosis. Cyanosis indicates respiratory failure and hence intubation and artificial ventilation are to be done especially if no improvement occurs with conservative measures

• Maintenance infusion of aminophylline can be started after loading dose at the rate of 0.6 mg/kg/hr (250 mg or 500 mg in 5% dextrose)
• Antibiotics if infection is present. Very often respiratory infection as the cause of acute exacerbation is over looked due to many reasons; hence it is preferable to add antibiotics early. Ampicillin or Amoxycillin is enough as these cover the common organisms. But modify the antibiotic regime when a serious respiratory infection is suspected
• Treat pneumothorax, if present
• Once the patient can take orally, start oral feeds, switch over to oral medications and taper steroid dose
• Erosive gastritis can develop in the acute phase. Liquid antacids or Ranitidine, may be used to prevent it.