Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020672 (hypothermia)
 17,327 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We continuously monitored blood oxygen saturation in the internal jugular vein during selective cerebral perfusion for aortic arch operations and evaluated its efficacy as an indicator of cerebral oxygen metabolism. The selective cerebral perfusion method was applied in 11 patients who underwent operations for aortic arch replacement. Blood oxygen saturation in the internal jugular vein was continuously monitored at the bulbus jugularis with a fiberoptic catheter during the operation. Perfusion flow of 500 ml/min was continued for 134.7 +/- 14.9 minutes under moderate hypothermia at 25 degrees C, and bilateral temporal arterial pressure was 40 to 60 mm Hg. Blood gas data were used to estimate oxygen consumption, oxygen extraction ratio, and lactate uptake in the cerebrum. No patients had postoperative cerebral complications. Cerebral oxygen consumption was 2.93 +/- 0.4 ml/min/100 gm under general anesthesia at 36 degrees C. While selective cerebral perfusion at 25 degrees C decreased consumption to 0.92 +/- 0.39 ml/min/100 gm, it fell to about 30% of its former value. Blood oxygen tension in the internal jugular vein showed no significant correlation with rectal temperature. Selective cerebral perfusion did not significantly affect cerebral lactate uptake. In contrast, blood oxygen saturation in the internal jugular vein was significantly affected by temperature and cerebral flow during selective cerebral perfusion, and blood oxygen saturation in the internal jugular vein correlated closely with cerebral oxygen extraction ratio (r = 0.91). Cerebral oxygen metabolism was thus well maintained, and continuous monitoring of blood oxygen saturation in the internal jugular vein was found to serve as a useful indicator under selective cerebral perfusion during operations for aortic arch replacement.
 ...
PMID:Continuous monitoring of blood oxygen saturation of internal jugular vein as a useful indicator for selective cerebral perfusion during aortic arch replacement. 173 1

Sublingual body temperatures were measured before and at 0.5, 1, 2, 3, 4, 8, 12, and 24 hours after administration of epidural or subarachnoid morphine in four groups of patients (n = 15 in each group) undergoing cesarean delivery with regional anesthesia. All patients were acutely hydrated with 1200 ml warmed lactated Ringer's solution. Group 1 received 5 mg epidural morphine; Group 2, 5 ml epidural saline; Group 3, 0.5 mg subarachnoid morphine, and Group 4, 0.5 ml subarachnoid saline. The results were expressed as means +/- SEM and analyzed using analysis of variance at p less than 0.05. Body temperature decreased significantly in all the four groups after anesthesia. The maximum decreases in Groups 1, 2, 3, and 4, respectively, were 0.95 +/- 0.1, 0.9 +/- 0.1, 1.4 +/- 0.2, and 0.8 +/- 0.13 degrees C and occurred at 0.5, 1, 2, and 1 hour, respectively. The decrease was greater in the subarachnoid morphine group than in the other groups (p less than 0.03). At any of the measurement periods, the temperatures in the two epidural groups did not differ from each other. However, the temperature in the subarachnoid morphine group remained significantly lower than the corresponding temperature in the control group for up to 24 hours. It is concluded that subarachnoid morphine intensifies the hypothermic action of spinal anesthesia in parturients.
 ...
PMID:The hypothermic action of epidural and subarachnoid morphine in parturients. 177 16

Tympanic, rectal, and axillary temperatures were measured and compared in 12 ASA Physical Status I and II parturients during epidural anesthesia for cesarean delivery. Measurements were performed before (T0) and at 15 (T1), 30 (T2), 45 (T3), and 60 (T4) minutes after epidural anesthesia. At birth, rectal neonatal and maternal temperatures were measured. Before anesthesia, maternal tympanic and rectal temperatures were statistically not different but higher than axillary temperature (difference, 0.5 degrees C). During anesthesia, all three maternal temperatures decreased. There was no difference for the first 45 minutes between rectal and tympanic membrane temperatures and no difference between tympanic and axillary temperatures after 30 minutes. The difference between rectal and tympanic temperatures became significant at T4. During the same period, the difference between axillary and tympanic temperatures became nonsignificant at T3 and T4. At birth, both maternal and newborn rectal temperatures were similar at 36.0 +/- 0.2 degrees C. The relative hypothermia observed in the newborns at birth after regional anesthesia was well correlated with the decrease in maternal temperature. A decrease in tympanic temperature of 1.4 degrees C developed during the course of epidural anesthesia for cesarean delivery. This decrease was underestimated by the measurement of rectal and axillary temperatures.
 ...
PMID:Temperature monitoring during epidural anesthesia for cesarean delivery. 177 15

A case of urgent application of craniocerebral hypothermia (CCH) during correction of traumatic mitral insufficiency developing in the course of closed mitral commissurotomy is described. The occlusion duration was 46.5 min, with the temperature in the esophagus 30.2 degrees C. No postoperative neurological disturbances have been observed. Three years after surgery the patient was in a satisfactory condition. It is demonstrated that CCH is associated with a more marked antihypoxic effect, than it has been earlier believed, and that it is possible to use intravenous ketamine anesthesia during CCH in patients with low cardiac output syndrome.
 ...
PMID:[A case of long-term occlusion in craniocerebral hypothermia]. 178 92

The physiological response to body cooling may be regarded as a homeostatic response embracing the concept of negative feedback. The metabolic response to falling body temperature is normally both appropriate and adequate. However, there are reports of inadequate or absent responses to body cooling and of non-febrile animals shivering at elevated body temperature. The reasons for these paradoxical findings are not fully understood, particularly since the controller of body temperature receives the largest proportion of its thermal afferent information from temperature sensors located within the body core. During anaesthesia and certain phases of sleep the shivering response to hypothermia may be impaired. It also appears that other factors such as the rate of cooling and disturbances of the circadian machinery (altered light conditions, phase shifting of activity patterns) may be of importance. These factors are relevant for people working in the arctic, especially since many of them are shift workers.
 ...
PMID:The shivering response in animals and man. 181 73

Severe accidental hypothermia is often associated with global ischaemia due to cardiac arrest. The purpose of the present study was to evaluate whether rewarming on cardiopulmonary bypass (CPB) should be slow or as fast as possible. Pigs were cooled to 23 degrees C (rectum), subsequently followed by 1 h period of circulatory arrest, whereupon rewarming was started. Pigs were randomly allocated to 3 groups: slowly rewarmed (2 h), rapidly rewarmed (0.5 h) and a control group on CPB maintaining normothermia. EEG was continuously analyzed by means of Anesthesia-Brain-Monitor (ABM-system), which allows simultaneous monitoring of EEG, blood- and intracranial pressures, heart rate and capnogram as trend graphs. The ABM-system thus delivers a continuous on-line printout of all measured variables. Cooling resulted after about 30 min in electrocerebral inactivity (ECI) in all pigs. EEG reappeared in all animals regardless of the considerable long cardiocirculatory arrest, followed by nearly 3 hours of ECI! It would appear tempting to rewarm an accidentally cooled organism as fast as possible. The present study, however, indicate that the brain during rewarming seems to have its own speed for regeneration of the EEG. This speed showed to be slower than the steeply rising temperature during rapid rewarming. Furthermore, a too vigorous rewarming may jeopardize cerebral metabolism; 90 min after the start of rewarming the EEG had reappeared in 5 out of 8 pigs in slow group, but only in 2 out of 7 in rapidly rewarmed animals. In controls the EEG was continuously present throughout the experiments.
 ...
PMID:Neuromonitoring in hypothermia and in hypothermic hypoxia. 181 76

It has been proposed that lithium ion desensitizes neuronal receptors that function via the inositol phospholipid signaling mechanism. We examined the effects of lithium chloride on the morphologic outcome after 5 minutes of cerebral ischemia induced in gerbils by occluding both common carotid arteries under brief halothane anesthesia. In three treated groups of 10 gerbils each, 5 meq/kg i.p. lithium chloride was given 2 days, 1 day, and 2 hours before ischemia; 2 hours before ischemia; or immediately after the end of ischemia. Corresponding control groups of nine or 10 gerbils each received equivalent volumes of saline injected at comparable times. All gerbils were perfusion-fixed 1 week later, and neuronal density of the hippocampal CA1 pyramidal cells was determined. Lithium induced very mild intraischemic systemic hypothermia, but postischemic hyperthermia developed in both treated and control groups. Neuronal densities were equal in corresponding groups. The results indicate that our regimen of lithium administration provides no benefit in survival of hippocampal neurons, and intraischemic hypothermia of less than 0.8 degrees C is not protective. Other strategies to inactivate the signal transduction system that is specific for excitatory neurotransmission should be evaluated.
 ...
PMID:Lithium ion does not protect brain against transient ischemia in gerbils. 184 49

Few safe and effective anesthesia regimens have been described for use in rabbits, partially because of the susceptibility of this species to sometimes fatal respiratory depression. Although inhalant anesthetics are generally safer than injectable anesthetics, their use may be limited by lack of equipment or facilities. This study was conducted to compare effects of several injectable anesthetics in rabbits on response to noxious stimuli, heart rate, respiratory rate, and rectal temperature. Six injectable anesthetic combinations were administered to rabbits: xylazine-ethyl-(1-methyl-propyl) malonyl-thio-urea salt (EMTU), ketamine-EMTU, xylazine-pentobarbital, xylazine-acepromazine-ketamine (XAK), ketamine-chloral hydrate, and ketamine-xylazine. All combinations induced a depression of respiratory rate. Although rectal temperature values were reduced to some degree in each group, the most profound hypothermia was induced by XAK. The combination that induced the longest duration of anesthesia was XAK. It was concluded that XAK was preferable for longer periods of anesthesia (60 to 120 minutes), although it induces severe hypothermia. For short periods of anesthesia, xylazine-pentobarbital, xylazine-EMTU, or ketamine-xylazine were deemed adequate; however, xylazine-EMTU induced the best survivability and consistency.
 ...
PMID:Comparison of several combinations for anesthesia in rabbits. 185 90

The blood/gas solubility coefficient and blood concentration of enflurane were measured at intervals in 10 patients undergoing coronary artery revascularization with cardiopulmonary bypass (CPB) and moderate hypothermia. A constant end-tidal concentration of enflurane was maintained throughout the study. Blood/gas solubility coefficient was determined at 37 degrees C, which when combined with an initial single-step equilibration of the blood sample with air, permitted the accurate measurement of blood concentration. Blood/gas solubility coefficient and blood concentration both decreased significantly with the onset of CPB. During the period of hypothermia, blood/gas solubility as measured at 37 degrees C showed little change; however, there was a progressive, marked increase in blood concentration with a mean increase of 80% prior to rewarming. Therefore, the level of anesthesia provided by enflurane may lighten with the onset of CPB, and a deeper level will accompany any decrease in blood temperature. On rewarming, blood concentration levels rapidly returned to levels similar to those measured before cooling. The increased uptake and accumulation of volatile anesthetic agent that occurred as a result of the period of hypothermic CPB was rapidly cleared. The rapidity with which blood concentration responded to the changes occurring during CPB make it unlikely that there was any significant increase in myocardial depression in response to the raised blood concentration secondary to the hypothermia.
 ...
PMID:Blood/gas solubility coefficient and blood concentration of enflurane during normothermic and hypothermic cardiopulmonary bypass. 186 23

While the cause of postanesthesia shaking (PS) remains unknown, nurses traditionally believe that the etiology of PS is hypothermia. Two theoretical constructs have been proposed to describe the development of PS. The first is based on classic thermoregulation theory. The second is based on spinal reflex hyperactivity. The purpose of this comparison study was to determine if significant differences in postoperative temperature, as well as change in preoperative to postoperative temperature, exists between patients who develop and who do not develop PS. The study also examined the difference in postoperative temperature between women and men. Postoperative axillary temperature was measured on admission to the PACU. The nonprobability convenience sample consisted of patients between the ages of 18 and 89 years who were extubated and breathing spontaneously following general anesthesia. PS developed in 120 of 533 patients. By t-test analysis, there was no statistical significant difference between groups in postoperative mean temperature (P greater than .10) or in preoperative to postoperative mean temperature change (P greater than .40). The group that developed PS had a narrower and higher range of postoperative temperature and a smaller preoperative to postoperative temperature change than those who did not develop PS. In both groups, 52% of the patients were hypothermic (less than 35 degrees C[less than 95 degrees F]) on PACU admission. Women had lower postoperative mean temperature than men (P less than .05). Findings indicate that temperature on PACU admission is not a variable of difference between groups of patients who develop or who do not develop PS. As postoperative temperature decreases, the incidence of PS does not increase.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Patients who develop postanesthesia shaking show no difference in postoperative temperature from those who do not develop shaking. 186 76


<< Previous 1 2 3 4 5 6 7 8 9 10