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)

Acute postoperative hypertension (APH) has been documented in the PACU. Over half of the patients who exhibit APH have pre-existing primary hypertension. Sustained blood pressure (BP) elevation increases the risk of myocardial ischemia, infarction, surgical site bleeding, or cerebral hemorrhage in these patients. Following surgery and anesthesia, increased sympathetic stimulation caused by a high level of circulating catecholamines can lead to APH. Some direct perioperative stimulants include pain, anxiety, hypoxia, hypercapnia, hypothermia, shivering, volume overload, and bladder distension. Nursing interventions are directed toward identifying and relieving the cause of APH. Antihypertensive drug therapy with vasodilators or adrenergic inhibitors is used if initial nursing interventions are not effective. Vasodilators frequently used are hydralazine, sodium nitroprusside, and nitroglycerin. Nicardipine has recently been introduced as an intravenous calcium channel blocker. Vasodilators are effective in BP reduction but may cause reflex tachycardia when used alone. Adrenergic inhibitors, such as esmolol and labetalol, block alpha and/or beta receptors to decrease heart rate and BP. Labetalol's effectiveness, relative freedom from side effects, and ease of administration have made it a useful drug in the treatment of APH.
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PMID:Acute postoperative hypertension in the hypertensive patient. 173 70

We investigated the ventilatory responses to hypoxia and hypercapnia in patients with essential hypertension (HT) as compared with healthy subjects (NV). Further, to evaluate the contribution of the peripheral chemoreceptors to ventilatory response, we used a withdrawal test. Hypoxic ventilatory drive (HVR) was measured as the parameter A denoting the shape of VI (inspiratory minute ventilation)-PETO2 (end-tidal PO2) curve which was calculated by the empirical equation: VI = V0 + A/(PETO2-32). Hypercapnic ventilatory drive (HCVR) was measured as the parameter S denoting the shape of the VI-PETCO2 (end-tidal PCO2) relation which was calculated by the empirical equation: VI = S(PETCO2-B). There were no significant differences in the parameters of HVR and HCVR between NV and HT. A positive correlation between A/BSA and S/BSA was found to be significant in NV (r = 0.873, p less than 0.05). Conversely, there was no significant correlation between A/BSA and S/BSA (r = 0.547) in HT. On the other hand, the withdrawal responses (delta VI/BSA and % delta VI:delta VI/VI x 100%) were obtained from the magnitude of depression in ventilation caused by two breaths of O2 in hypoxic hypercapnia. In the withdrawal responses, delta VI/BSA and % delta VI in HT were significantly higher than those in NV. A/BSA significantly correlated with delta VI/BSA (NV, r = 0.684, p less than 0.05; HT, r = 0.648, p less than 0.05) in both NV and HT. However, delta VI/BSA in HT tended to be higher than that in NV, under the same value of A/BSA. These results suggested that the peripheral chemoreceptor activity was augmented in HT.
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PMID:Ventilatory responses in patients with essential hypertension. 180 69

Primary hypertension is associated with decreased performance on neurocognitive testing and a blunted cerebrovascular reactivity to hypercapnia. Parents of 14 children with hypertension and prehypertension completed the Behavior Rating Inventory of Executive Functions. Children underwent 24-hour ambulatory blood pressure monitoring and transcranial Doppler with reactivity measurement using time-averaged maximum mean velocity and end-tidal carbon dioxide during hypercapnia-rebreathing test. Comparing the reactivity slope for the patients to historical controls showed a statistically significant difference (t = -5.19, df = 13, P < .001), with lower slopes. Pearson correlations of the Behavior Rating Inventory of Executive Functions scores with the reactivity slopes showed a statistically significant inverse relationship with Behavioral Regulation Index (r = -.60, P = .02), Metacognition Index (r = -.40, P = .05), and the Global Executive Component (r = -.53, P = .05). Children with hypertension have decreased executive function, and this correlates to low transcranial Doppler-reactivity slopes, suggesting that the brain is a target organ in hypertensive children.
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PMID:Executive function and cerebrovascular reactivity in pediatric hypertension. 2387 80