Effects of fenoterol and ipratropium on respiratory resistance of asthmatics after tracheal intubation

Acute Severe Asthma in Adolescent and Adult Patients: Current Perspectives on Assessment and Management

Asthma is a chronic airway inflammatory disease that is associated with variable expiratory flow, variable respiratory symptoms, and exacerbations which sometimes require hospitalization or may be fatal. It is not only patients with severe and poorly controlled asthma that are at risk for an acute severe exacerbation, but this has also been observed in patients with otherwise mild or moderate asthma. This review discusses current aspects on the pathogenesis and pathophysiology of acute severe asthma exacerbations and provides the current perspectives on the management of acute severe asthma attacks in the emergency department and the intensive care unit.

Essentials of Pulmonology

Pulmonary complications are a major cause of perioperative morbidity in the pediatric population. Although preexisting pulmonary pathologic processes in children can present significant challenges to anesthetic delivery, a thorough assessment of the problem combined with meticulous anesthetic management allows most children to undergo surgical interventions without long-term adverse sequelae. Asthma, cystic fibrosis and sickle cell disease continue to pose challenges during anesthesiology. Consultation with a pediatric pulmonologist is indicated when appropriate for specific problems as outlined in this chapter; a team approach may markedly improve operative and postoperative outcomes.

Perioperative Evaluation of Patients with Pulmonary Conditions Undergoing Non-Cardiothoracic Surgery

This review describes the perioperative management of patients with suspected or established pulmonary conditions undergoing non-cardiothoracic surgery, with a focus on common pulmonary conditions such as obstructive airway disease, pulmonary hypertension, obstructive sleep apnea, and chronic hypoxic respiratory conditions. Considering that postoperative pulmonary complications are common and given the increasing number of surgical procedures and the size of the aging population, familiarity with current guidelines for preoperative risk assessment and intra- and postoperative patient management is recommended to decrease the morbidity and mortality. In particular, smoking cessation and pulmonary rehabilitation are perioperative strategies for improving patients’ short- and long-term outcomes. Understanding the potential risk for pulmonary complications allows the medical team to appropriately plan the intra- and postoperative care of each patient.

Anesthesia and ventilation strategies in children with asthma: part I - preoperative assessment

PURPOSE OF REVIEW

Asthma is a common disease in the pediatric population, and anesthetists are increasingly confronted with asthmatic children undergoing elective surgery. This first of this two-part review provides a brief overview of the current knowledge on the underlying physiology and pathophysiology of asthma and focuses on the preoperative assessment and management in children with asthma. This also includes preoperative strategies to optimize lung function of asthmatic children undergoing surgery. The second part of this review focuses on the immediate perioperative anesthetic management including ventilation strategies.

RECENT FINDINGS

Multiple observational trials assessing perioperative respiratory adverse events in healthy and asthmatic children provide the basis for identifying risk factors in the patient's (family) history that aid the preoperative identification of at-risk children. Asthma treatment outside anesthesia is well founded on a large body of evidence. Optimization and to some extent intensifying asthma treatment can optimize lung function, reduce bronchial hyperreactivity, and minimize the risk of perioperative respiratory adverse events.

SUMMARY

To minimize the considerable risk of perioperative respiratory adverse events in asthmatic children, a good understanding of the underlying physiology is vital. Furthermore, a thorough preoperative assessment to identify children who may benefit of an intensified medical treatment thereby minimizing airflow obstruction and bronchial hyperreactivity is the first pillar of a preventive perioperative management of asthmatic children. The second pillar, an individually adjusted anesthesia management aiming to reduce perioperative adverse events, is discussed in the second part of this review.

Guideline-oriented perioperative management of patients with bronchial asthma and chronic obstructive pulmonary disease

Increased airway hyperresponsiveness is a major concern in the perioperative management of patients with bronchial asthma and chronic obstructive pulmonary disease. Guidelines using evidence-based medicine are continually being updated and published regarding the diagnosis, treatment, and prevention of these respiratory disorders. Perioperative management in these patients involves: (1) adequate control of airway hyperresponsiveness, including detection of purulent sputum and infection before surgery; (2) evidence-based control of anesthesia; and (3) the aggressive use of beta-2 adrenergic stimulants and the systemic administration of steroids for the treatment of acute attacks. Good preoperative control, including the use of leukotriene antagonists, can reduce the incidence of life-threatening perioperative complications. Awareness of recent guidelines is thus important in the management of patients with airway hyperresponsiveness. This review covers the most recent guidelines for the perioperative management of patients with bronchial asthma and chronic obstructive pulmonary disease.

Salbutamol prevents the increase of respiratory resistance caused by tracheal intubation during sevoflurane anesthesia in asthmatic children

Asthmatic children having their tracheas intubated with sevoflurane often have an increase in respiratory system resistance (Rrs). In this randomized, placebo-controlled, double-blinded study, we investigated the protective effect of an inhaled beta2-adrenergic agonist. Either salbutamol or placebo was administered 30 to 60 min before anesthesia to 30 mildly to moderately asthmatic children scheduled for elective surgery. Induction was performed with sevoflurane in a mixture of 50% nitrous oxide in oxygen and maintained at 3%, with children breathing spontaneously via a face mask and Jackson-Rees modification of the T-piece. Airway opening pressure and flow were measured before and after insertion of an oral endotracheal tube. Rrs and respiratory system compliance were calculated with multilinear regression analysis. The groups were comparable with respect to age, weight, asthma history, and breathing pattern. Intubation induced a different Rrs response in the two groups: children treated with salbutamol showed a 6.0% (-25.2% to +13.2%) decrease (mean, 95% confidence interval), whereas in the Placebo group there was a 17.7% (+4.4% to +30.9%) increase (P = 0.04). Neither asthma history nor the serum inflammation marker eosinophilic cationic protein was predictive for this response. We conclude that when using sevoflurane in mildly to moderately asthmatic children, a preanesthetic treatment with inhaled salbutamol is protective of an increase in Rrs.

IMPLICATIONS

Tracheal intubation with sevoflurane as the sole anesthetic is now often performed in children. It can induce an increase in respiratory system resistance in children with asthma. This study shows that in children with mild to moderate asthma, a preanesthetic treatment with inhaled salbutamol can prevent the increase of respiratory system resistance.