Effect of intravenous antibiotics on exercise tolerance (3-min step test)) in cystic fibrosis.

Abstract

Most children with cystic fibrosis (CF) feel better and display more energy after a course of intravenous antibiotics (IVABs), but this is not always reflected by a satisfactory improvement in lung function. We assessed the change in exercise tolerance after treatment with IVABs using the 3-min step test, and compared it with changes in spirometric lung function and arterial oxygen saturation (SaO(2)). Thirty-six children (mean age, 13.8 years) were enrolled from two tertiary CF centers during an inpatient stay for IVABs. After 10-14 days of treatment, there was a significant improvement in median FEV(1) from 43% to 57% of predicted values (P < 0.0001), and median FVC from 66% to 73% of predicted values (P < 0.0001), while median SaO(2) significantly increased from 95% to 96.5% (P < 0.05). This was accompanied by a reduction in resting heart rate (median 118 bpm to 109 bpm, P < 0.005) and subjective breathlessness at rest (median visual analogue score 2.2 to 0.8, P < 0.005). All outcomes of exercise tolerance were improved after IVABs. There was a reduction in maximum heart rate (median 156 bpm to 150 bpm, P < 0.05) and an increase in minimum SaO(2) (median 93.5% to 94.5%, P = 0.08) measured during the step test. There was also a reduction in subjective breathlessness (median visual analogue score of 5.5 to 4.2, P < 0.005) and objective breathlessness (median 15-count score of 3 to 2, P < 0.0001) measured immediately after the step test. Exercise testing was a useful outcome measure for monitoring effectiveness of inpatient therapy, and complemented spirometry and SaO(2) monitoring. The simple ward-based 3-min step test was found to be a particularly suitable method for measuring changes in exercise tolerance in children with CF.

• Authors: S E Pike, S A Prasad, I M Balfour-Lynn
• Journal: Pediatric pulmonology (Pediatr Pulmonol) Vol. 32 Issue 1 Pg. 38-43 (Jul 2001) ISSN: 8755-6863 [Print] United States
• PMID: 11416874 (Publication Type: Clinical Trial, Journal Article)
• Copyright: Copyright 2001 Wiley-Liss, Inc.

Chemical References

• Anti-Bacterial Agents
• Oxygen

Topics

• Adolescent
• Anti-Bacterial Agents
• Child
• Cystic Fibrosis (drug therapy, physiopathology)
• Drug Therapy, Combination (administration & dosage, therapeutic use)
• Exercise Test
• Exercise Tolerance (drug effects)
• Female
• Forced Expiratory Volume (drug effects)
• Heart Rate (drug effects)
• Humans
• Injections, Intravenous
• Male
• Oxygen (blood)
• Prospective Studies
• Respiratory Function Tests
• Treatment Outcome