Nebulised salbutamol does have a protective effect on airways in children under 1 year old.

Abstract

SUMMARY Ten infants under the age of 1 year each of whom gave a history of recurrent wheezing attacks were studied with a total body plethysmograph. All the infants were free of wheeze when studied and were sedated with chloral hydrate. All 10 showed a significant deterioration in lung function when given nebulised water for two minutes with an increase in airways resistance and a decrease in specific conductance at one and five minutes after nebulisation compared with baseline readings. Measurements returned to baseline values within 15 minutes. When the same amount of nebulised water was given 20 minutes after nebulised salbutamol, however, there was no significant deterioration in lung function at one and five minutes after administration of nebulised water.We conclude that the airways were protected against the bronchoconstricting effect of nebulised water by the 12 adrenoreceptor stimulant salbutamol.Many doctors believe that (32 adrenoreceptor stimulants have little or no effect on the airways of infants under the age of 1 year. These children do, however, have (2 adrenoreceptors' and smooth muscle2 in their airways and theoretically should respond to (32 adrenergic stimulants. Nebulised water has a bronchoconstricting effect on asthmatic children and adults,37 and we have found that it also causes bronchoconstriction in wheezy infants (unpublished data).The present study was designed to find out if nebulised salbutamol protects the airways of wheezy infants. Nebulised water was used as a bronchoconstricting challenge. Patients and methodsPatients studied were under 1 year old and attending this hospital for routine assessment. All had had more than two wheezy episodes in the preceding months. Table 1 shows their age, sex, and history of bronchiolitis. At the time of the study all were clinically well and at least four months had elapsed since their bronchiolitic illnesses. Each study was done in the outpatient clinic, all patients were awake, and allowed home within three hours of arrival.The infants were sedated with chloral hydrate (120 mg/kg), and thoracic gas volume and airways resistance were measured with total body plethysmography.i" The total body plethysmograph had a capacity of 260 litres, and a servo controlled heating system maintained the face mask, shutter system, and rebreathing bag at 36°C. Thoracic gas volume was measured at the end of inspiration, and the tidal volume was subtracted before calculation. The children were nursed supine and firm latex masks applied to their faces. The dead space of each mask was 88 ml. There was a bias flow of air at 5 1/minute to the face mask. Signals were relayed to the axis of a cathode ray oscilloscope, all readings were made by the same observer,

Inhaled salbutamol for wheezy infants: a randomised controlled trial

“…14 20 21 We could not show this benefit being carried over to protection against (probable) virus induced wheeze as our infants did not show any reduction in “exacerbations” (defined as days with high symptom score). This may indicate that the mechanisms behind naturally triggered wheeze in infancy are different from wheeze induced by chemical challenge.…”

“…Documented adverse responses to a single dose of salbutamol include hypoxaemia,7 8increased airways resistance,9 10 and a decline in forced expiratory flow 611 12 The most repeatable beneficial effect of salbutamol has been to abolish or reduce the bronchoconstrictor response to histamine13 or water 14. One problem of single dose studies is that the infant is often asymptomatic on the day of testing, which may mask any response.…”

Corticosteroids do not affect the clinical or physiological status of infants with bronchiolitis

“…*' Lower than expected TGV values in postbronchiolitic infants were apparent in the studies of at least two other groups. O'Callaghan et al , 21 reporting the response to ultrasonically nebulized water in ten infants with a history of wheezing, showed TGV in three infants to be less than 25 mL/kg. Seidenberg et reported the changes in pulmonary function in 14 infants with bronchiolitis.…”

A comparison between nebulized terbutaline, nebulized corticosteroid and systemic corticosteroid for acute wheezing in children up to 18 months of age

“…Several studies have evaluated the clinical effect of these drugs using a score system (1 -9). Some investigators have tried to evaluate the effect using pulmonary function tests (3,(10)(11)(12)(13)(14)(15)(16). The results are conflicting, and therefore there is no commonly accepted treatment for acute wheezing in young children.…”