Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020672 (hypothermia)
 17,327 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

The spontaneously hypertensive rat (SHR) is a widely used animal model for essential hypertension, and is less susceptible to cold restraint stress in gastric ulcer formation. We previously reported that acid secretion is low in SHR due to sympathetic facilitation compared with normotensive Wistar-Kyoto rats (WKY). The purpose of this study was to evaluate the autonomic nervous function and the gastric mucosal blood flow related to gastric motility during cold restraint stress in SHR. Male SHR and WKY, 24-28 weeks old, were used in this study. Noradrenergic innervation, noradrenaline and dopamine contents in the muscle layer were significantly greater in SHR than in WKY, and tissue choline acetyltransferase activity was significantly lower in SHR. Gastric motility was markedly enhanced by cold restraint stress in WKY. By contrast, SHR maintained the rhythmic and low amplitude contractions regardless of hypothermia. Mucosal blood flow decreased markedly during hypothermia in WKY but was well sustained in SHR. In conclusion, the increase in gastric motility associated with cold restraint stress was suppressed in SHR by sympathetic facilitation in the muscle layer, and this may have contributed to the prevention of ulcer formation by maintaining mucosal blood flow in SHR.
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PMID:Gastric mucosal blood flow in relation to stress-induced hypercontraction in spontaneously hypertensive rats. 776 May 25

The central autonomic network (CAN) is an integral component of an internal regulation system through which the brain controls visceromotor, neuroendocrine, pain, and behavioral responses essential for survival. It includes the insular cortex, amygdala, hypothalamus, periaqueductal gray matter, parabrachial complex, nucleus of the tractus solitarius, and ventrolateral medulla. Inputs to the CAN are multiple, including viscerosensory inputs relayed on the nucleus of the tractus solitarius and humoral inputs relayed through the circumventricular organs. The CAN controls preganglionic sympathetic and parasympathetic, neuroendocrine, respiratory, and sphincter motoneurons. The CAN is characterized by reciprocal interconnections, parallel organization, state-dependent activity, and neurochemical complexity. The insular cortex and amygdala mediate high-order autonomic control, and their involvement in seizures or stroke may produce severe cardiac arrhythmias and other autonomic manifestations. The paraventricular and other hypothalamic nuclei contain mixed neuronal populations that control specific subsets of preganglionic sympathetic and parasympathetic neurons. Hypothalamic autonomic disorders commonly produce hypothermia or hyperthermia. Hyperthermia and autonomic hyperactivity occur in patients with head trauma, hydrocephalus, neuroleptic malignant syndrome, and fatal familial insomnia. In the medulla, the nucleus of the tractus solitarius and ventrolateral medulla contain a network of respiratory, cardiovagal, and vasomotor neurons. Medullary autonomic disorders may cause orthostatic hypotension, paroxysmal hypertension, and sleep apnea. Neurologic catastrophes, such as subarachnoid hemorrhage, may produce cardiac arrhythmias, myocardial injury, hypertension, and pulmonary edema. Multiple system atrophy affects preganglionic autonomic, respiratory, and neuroendocrine outputs. The CAN may be critically involved in panic disorders, essential hypertension, obesity, and other medical conditions.
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PMID:The central autonomic network: functional organization, dysfunction, and perspective. 841 66

Abnormalities in autonomic activity resulting in disturbances of the diurnal rhythm of many physiologic processes were recently revealed in hypertensive patients. These findings suggest deteriorations in the functioning of the suprachiasmatic nucleus (SCN), which is known to be the biological clock of mammals. To test this hypothesis, we carried out an immunocytochemical study of the SCN of primary hypertension patients who had died due to myocardial infarction or brain hemorrhage, and compared them with those of individuals with a normal blood pressure who had never had any autonomic disturbances and died from myocardial infarction after chest trauma or from hypothermia. We found that the staining for the three main neuronal populations of the SCN; i.e., vasopressin, vasoactive intestinal polypeptide, and neurotensin, reduced by more than 50% in the hypertensives compared with controls. The present data indicate a serious dysregulation of the biological clock in hypertensive patients. Such a disturbance may cause a harmful hemodynamic imbalance with a negative effect on circulation, especially in the morning, when the inactivity-activity balance changes. The difficulty in adjusting from inactivity to activity might be involved in the morning clustering of cardiovascular events.
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PMID:Neuropeptide changes in the suprachiasmatic nucleus in primary hypertension indicate functional impairment of the biological clock. 1117 8