Preoperative management of asthma
Preoperative management of asthma
In patients with reversible airway obstruction and bronchial reactivity, preoperative treatment with β2-adrenergic agonists and corticosteroids should be considered. β2-adrenergic agonists have been shown to attenuate the reflex bronchoconstriction following endotracheal intubation. Even with this intervention, significant bronchoconstriction and wheezing occurs following intubation.
Combined treatment with corticosteroids and a β2-adrenergic agonist can improve preoperative lung function and decrease the incidence of wheezing following endotracheal intubation.
Concerns about negative effects of perioperative treatment with corticosteroids in terms of wound healing and infection were not supported by studies in asthmatic patients receiving prophylactic treatment with corticosteroids perioperatively, and there is evidence that asthmatic patients who are treated with corticosteroids can undergo surgical procedures with a low incidence of complications.
Thus, preoperative treatment struction or with a history of severe bronchial hyper-reactivwith combined corticosteroids [methylprednisolone (40 mg/day orally)] and salbutamol minimizes intubation-evoked bronchoconstriction in patients with reversible airway obity.
According to Enright, preoperative management in asthmatics should include the following
measures:
1. bronchospasm should be treated with inhaled β2-agonists;
2. if a patient is at risk for complications, pre-operative treatment with 40-60 mg of prednisone/day or hydrocortisone 100 mg every 8 h intravenously is suggested. Anyone with a preoperative FEV1<80% of predicted should receive steroids;
3. infections should be eradicated using antibiotics;
4. fluid and electrolyte imbalances should be corrected, given that high dose β2-agonists can
cause hypokalemia, hyperglycemia, and hypomagnesemia. In addition to that imbalance, there may
be a decreased response to β2-agonists and predisposition to cardiac arrhythmias;
5. prophylactic cromolyn treatment to prevent
degranulation of mast cells and release of mediators should be continued;
6. chest physiotherapy improves sputum clearance and bronchial drainage;
7. other conditions such as cor pulmonale should be treated;
8. the patient should stop smoking in order to reduce carboxyhemoglobin levels.