Physical exercise effect on certain acid-base equilibrium parameters in children with small ventricular septal...

Area of Science:

• Pediatric Cardiology
• Exercise Physiology
• Biochemistry

Background:

• Ventricular septum defects (VSDs) are common congenital heart abnormalities.
• Understanding the physiological responses to exercise in children with VSDs is crucial for management.
• Acid-base balance during exertion is a key indicator of cardiovascular and metabolic function.

Purpose of the Study:

• To investigate acid-base equilibrium in children with VSDs during varying physical exercise intensities.
• To compare the exercise-induced metabolic and respiratory responses between children with VSDs and healthy controls.

Main Methods:

• Studied 47 children (7-16 years): 28 with VSDs and 19 healthy controls.
• Measured blood pH, base excess (BE), and pCO2 using Astrup microapparatus on arterialized capillary blood.
• Assessed acid-base parameters during three exercise levels: normal locomotion, moderate (170-180 bpm), and high intensity (190 bpm).

Main Results:

• Children with VSDs showed a significantly greater tendency towards metabolic acidosis during all exercise workloads compared to controls.
• The difference in metabolic acidosis was more pronounced in children with VSDs during high-intensity exercise versus lower intensities.
• Respiratory parameters also showed differences, though the primary finding related to metabolic changes.

Conclusions:

• Children with small VSDs exhibit impaired metabolic compensation during physical exertion.
• Exercise testing can reveal subclinical metabolic disturbances in pediatric cardiac patients.
• These findings highlight the importance of considering exercise capacity and acid-base status in VSD management.