Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085383 (hypocapnia)
 1,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to study the effects of PaCO2 and PaO2 on the laryngeal closure reflex, changes in laryngeal resistance of the isolated cat larynx were measured before and during the stimulation of the superior laryngeal nerve (SLN) at various levels of PaCO2 and PaO2. The results showed that laryngeal resistance before SLN stimulation [LR (baseline)] increased slightly during hypocapnia. SLN stimulation produced laryngospasm which was defined as a sharp rise in the laryngeal resistance. Hypercapnia alone and hypoxia alone increased ventilation but decreased the degree and duration of laryngospasm due to SLN stimulation. On the other hand, hypocapnia augmented and prolonged the duration of this laryngospasm. These results suggest that PaCO2 and PaO2 regulate the laryngeal closure reflex in a way such that the degree of laryngospasm changes in inverse proportion to the activity of the respiratory center.
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PMID:Modification of laryngospasm in response to changes in PaCO2 and PaO2 in the cat. 679 29

We present a woman with heterozygous carnitine palmitoyl transferase 2 (CPT-2) deficiency who in the last 6 months suffered from episodic dyspnea and choking. Symptoms could not be attributed to her muscular energy defect, since heterozygous CPT-2 deficiency is usually asymptomatic or causes only mild muscle fatigability. Myopathy is usually triggered by concurrent factors, either genetic (additional muscle enzymes defects) or acquired (metabolic stress). The patient was referred to our respiratory clinic for suspect bronchial asthma. Spirometry showed mild decrease in inspiratory flows. Methacholine challenge was negative. Dyspnea was triggered by hyperventilation-induced hypocapnia, which produced marked decrease in airflow rates, particularly in inspiratory flows, consistent with laryngospasm. Nutritional assessment of the patient showed low serum level of calcium and vitamin D, attributable to avoidance of milk and dairy products for lactose intolerance and to insufficient sunlight exposure. After calcium and vitamin D supplementation episodic laryngospasm disappeared and hypocapnic hyperventilation test induced very mild change in airflow rates. Calcium and vitamin D deficiency may favour laryngeal spasm mimicking asthma, particularly in subjects with underlying myopathy.
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PMID:Laryngeal spasm mimicking asthma and vitamin d deficiency. 2484 4