Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020440 (hypercapnia)
 7,939 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A peripheral neuropathy has been reported in patients with chronic respiratory insufficiency due to chronic obstructive pulmonary disease (COPD). It is mainly characterized by axonal degeneration, secondary demyelination and abnormal endoneurial vessels. The pathogenesis of these lesions remains obscure. To investigate whether relationships exist between neuritic and vascular lesions, a qualitative and quantitative ultrastructural study was performed on nerve biopsies in 13 patients with chronic respiratory insufficiency due to COPD, and in 9 normal controls without pulmonary lesions. A computer-assisted multiple regression analysis taking into account clinical, electrophysiological, biological and morphometric parameters was performed. Statistically significant differences in the endoneurial structure of microvessels were: (1) thickening of the basement membrane; (2) narrowing of the lumen; (3) mural pericytic debris deposits, occurring in the COPD group. In the latter, hypercapnia correlated positively with nerve fibers lesions (P = 0.03) and endothelial area (P = 0.03). No correlations were found between age and other parameters. These findings highlight the fact that the microangiopathy in peripheral nerves in patients with COPD may be diffuse and essentially due to hypoxia and reduction in blood flow, as in diabetic neuropathy.
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PMID:Microangiopathy of endoneurial vessels in hypoxemic chronic obstructive pulmonary disease (COPD). A quantitative ultrastructural study. 255 Nov 23

A 57-yr-old man with idiopathic central apnea is reported. He presented at our hospital complaining of excessive daytime sleepiness. Polysomnography, including esophageal pressure monitoring, confirmed central sleep apnea with an apnea index of 27/h. He had mild non-insulin-dependent diabetes mellitus (NIDDM) but no signs of diabetic neuropathy or other background diseases. The ventilatory responses to hypoxia and hypercapnia tested while he was awake indicated increased respiratory chemosensitivity. We applied nasal continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BPAP) in an attempt to compare the possible difference in therapeutic efficacy. Although nasal CPAP completely reversed central apnea, nasal BPAP adversely affected both apnea length and frequency in an applied pressure-dependent manner. Arterial blood gas analyses while he was being treated indicted alveolar hypoventilation with CPAP and hyperventilation with BPAP. Additionally, administration of a mixed gas containing 5% CO2 through a face mask had a significant effect on the disappearance of central apnea in this patient. These findings support the theory that the arterial PCO2 level is critical in generating idiopathic central apnea and that nasal CPAP therapy may be effective in eliminating central apnea by raising the PaCO2.
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PMID:Continuous versus bilevel positive airway pressure in a patient with idiopathic central sleep apnea. 910 99

We present a case of postural hypoxemia with a final diagnosis of myasthenia gravis (MG). A 62-year-old man experienced double vision in his left eye from December 2008 and received a diagnosis of diabetic neuropathy. From mid-December he began to experience breathing difficulties at night when in a supine position and was admitted to our hospital. Bilateral diaphragmatic elevation was observed on a chest X-ray film, and lower lung atelectasis and an anterior mediastinal tumor were observed on chest CT. However, his breathing difficulties only occurred when he was in a supine position. Therefore, we performed blood gas analysis in supine and sitting positions. Hypoxemia, hypercapnia and an increase in A-aDO2 were observed in the supine position, leading to a diagnosis of postural hypoxemia. Due to the exacerbation of his double vision, the patient was referred to the ophthalmology and neurology departments where he tested positive for anti-acetylcholine receptor antibodies and also on a tensilon test, resulting in a final diagnosis of MG. During the tensilon test, the patient's breathing difficulties in the supine position improved, and therefore his postural hypoxemia was thought to have resulted from diaphragmatic muscle weakness as a result of MG. MG respiratory failure is typically of the acute fulminating type and is considered to be a critical condition. However, it should be noted that there are cases, such as the present one, in which MG presents as postural hypoxemia.
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PMID:[A case of postural hypoxemia with a final diagnosis of myasthenia gravis]. 2235 50