Related Experiment Videos
Hormonal and electrolyte responses during and after open heart surgery
The Thoracic and Cardiovascular Surgeon
|December 1, 1984
Summary
Cardiopulmonary bypass can disrupt metabolic balance. This study found non-pulsatile bypass did not cause hypothalamo-pituitary-adrenal axis hypofunction when corrected for hemodilution, and PTH levels were linked to pH and hypothermia, not calcium.
Area of Science:
- Cardiovascular Surgery
- Endocrinology
- Metabolic Homeostasis
Background:
- Myocardial metabolism requires stable electrolytes and hormones.
- Open heart surgery with cardiopulmonary bypass disrupts metabolic homeostasis.
- Previous studies suggested non-pulsatile bypass causes pituitary-adrenal hypofunction.
Purpose of the Study:
- To investigate hypothalamo-pituitary-adrenal axis function during non-pulsatile cardiopulmonary bypass.
- To examine the relationship between parathyroid hormone (PTH), calcium, pH, and hypothermia during cardiopulmonary bypass.
Main Methods:
- Non-pulsatile cardiopulmonary bypass was employed.
- Hormonal levels (ACTH, cortisol, cortisone) were measured and corrected for hemodilution.
- Electrolyte levels, including ionized calcium, were monitored.
- Bioactive PTH levels were assessed in relation to calcium, pH, and temperature.
Main Results:
- No evidence of hypothalamo-pituitary-adrenal axis hypofunction was observed with non-pulsatile bypass after correcting for hemodilution.
- Significant increases in bioactive PTH during bypass were not correlated with calcium levels.
- PTH levels appeared influenced by low blood pH and degree of hypothermia.
Conclusions:
- Non-pulsatile cardiopulmonary bypass, when accounting for hemodilution, does not necessarily lead to hypothalamo-pituitary-adrenal axis hypofunction.
- The regulation of parathyroid hormone during cardiopulmonary bypass is complex, influenced by acid-base balance and temperature rather than solely by calcium concentration.