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)

In investigating the stress effects of chilling (2-3 degrees C) and hypothermia (2-3 degrees C drop in body core temperature mediated by exposure to hyperbaric helium-oxygen atmosphere) on mouse resistance to "influenza," it was noted that these stresses adversely affected the course of pulmonary infection produced by aerosols of the NWS strain of influenza virus. Comparatively, respiratory LD50 values for control animals were about 25 virus plaque-forming units (PFU) with median mortality occurring on day 13. The LD50 values for mice chilled at 2-3 degrees C were about 15 PFU with median mortality on day 7, and for mice exposed to hyperbaric helium, about 12 PFU with median mortality on day 6. Cold or hyperbaric stress impaired interferon production. Impairment was observed at 24 h but not at 12 h post-challenge and persisted for several days until mice became moribund.
 ...
PMID:Influence of cold or hyperbaric helium-oxygen environments on mouse response to a respiratory viral infection. 97 Nov 54

A 67-year-old man with symptomatic bilateral carotid artery obstructions and a large, friable atheromatous plaque of the transverse aortic arch required coronary artery bypass grafting for severe triple-vessel disease. An endarterectomy of the transverse arch and a left carotid endarterectomy were performed using deep hypothermic circulatory arrest concomitant with quadruple coronary artery bypass grafting. Recovery was uneventful. Hypothermic circulatory arrest provides adequate protection for this combined procedure and may eliminate cerebral embolization.
 ...
PMID:Carotid and aortic arch endarterectomy using hypothermic arrest with coronary bypass. 259 26

Two patients with clinically definite multiple sclerosis presented with acute hypothermia and on recovery were found to be chronically hypothermic. Thermoregulatory studies indicated a central, hypothalamic defect which is presumed to be due to a plaque of demyelination.
 ...
PMID:Chronic hypothermia in multiple sclerosis. 361 61

The experiments were carried out on normothermal rabbits and rabbits exposed to cold stress (hypothermia). The animals of the latter group were submerged in ice-water for 20 s and then placed in a freezer at -15 degrees C for 8 min until their body temperature dropped by 3 degrees C. Both the normothermal and hypothermal rabbits were immunized i.p. with 3 ml of 10% sheep red blood cells (SRBC). Levamisole (2 mg/kg), DTC (sodium diethyldithiocarbamate, 20 mg/kg) or mechlorethamine (mustine; 5 micrograms/kg) were injected i.v. three times at 24-h intervals. The number of PFC, total (19S + 7S) and 2-mercapthoethanol resistant (7S) serum haemagglutination titres were determined. It was found that, in normothermal rabbits, all three agents potentiated the number of plaque-forming cells (PFC); the impact of DTC was the strongest, while the weakest influence was observed for mechlorethamine. Furthermore, DTC increased anti-SRBC haemagglutinin titre, whereas mechlorethamine did not. Levamisole, on the other hand, reduced total serum haemagglutinin titre. Cold stress reduced humoral response to SRBC, which was reflected in the decreased number of PFC and serum haemagglutination titres (19S + 7S and 7S). Each agent showed a different way of action. Pretreatment with DTC prevented the immunosuppression caused by cold stress, while levamisole and mechlorethamine only reduced the immunosuppressive effect.
 ...
PMID:Effects of levamisole, DTC and low-dose mechlorethamine on humoral response of SRBC-immunized rabbits exposed to cold stress. 748 96

The application of a number of procedures that can be considered intraoperative endovascular neurosurgery has enhanced our ability to treat cerebral aneurysms from the abluminal surface. This study identifies a role for these techniques in the management of difficult aneurysms. A review of the last 1202 aneurysms undergoing direct clipping by the authors disclosed that these methods were used in 62 cases. Of these aneurysms, 36 arose from the internal carotid artery, 12 from the middle cerebral artery, eight from the vertebrobasilar distribution, and six from the anterior cerebral artery. The indications for applying these methods were large size (12-60 mm), intraluminal thrombus, broad neck, plaque at the neck, the potential compromise of branches at the base of the aneurysm, or a combination of these problems. The most frequently chosen intraoperative technique was suction decompression with direct removal of plaque and thrombus using suction, dissection, and/or ultrasonic aspiration. The application of temporary clips was required in all cases in which the aneurysm was opened before definitive clipping. No special pharmacological cerebral protective regimen was used. In one case in which a greater occlusion time was anticipated, cardiopulmonary bypass with profound hypothermia was performed. A favorable outcome was achieved in 73% of these difficult cases. An increased neurological deficit after surgery was seen in 11%, and the mortality rate was 8%. These methods should be considered and can be anticipated before surgery for unusual aneurysms. Many cases now being considered for embolization may be more suitable for definitive surgical obliteration.
 ...
PMID:Intraoperative endovascular surgery for cerebral aneurysms. 861 37

Hypothermic cardiopulmonary bypass alters platelet function and hypothermia is associated with postoperative myocardial ischemia. Thrombogenic surfaces such as extracorporeal circuits, vascular graft materials, and components of atherosclerotic plaque induce activation of platelets. The effects of human hemoglobin (Hb) covalently modified to carry S-nitric oxide (NO) functional groups (SNO-Hb), polyethylene glycol (PEG-Hb), and SNO-PEG-Hb on platelet activation were studied. Platelet activation was assessed by cytometric analysis of GPIIb-IIIa activation and P-selectin expression at hypothermic condition (22 degrees C) after stimulation with Hb derivatives. Platelet adhesion and aggregation were measured in a parallel glass plate chamber coated with unmodified Hb, SNO-Hb, PEG-Hb, SNO-PEG-Hb, and collagen. Platelet binding of antibodies to GPIIb-IIIa and P-selectin was significantly enhanced by hypothermic condition and by unmodified Hb. There was significantly less platelet binding of antibodies to GPIIb-IIIa and P-selectin with SNO-Hb, PEG-Hb, and SNO-PEG-Hb compared with unmodified Hb. There was significantly less platelet attachment, adhesion, and aggregation on the SNO-Hb, PEG-Hb and SNO-PEG-Hb coated surfaces compared with unmodified Hb-coated and -uncoated surfaces. SNO-Hb, PEG-Hb, and SNO-PEG-Hb induced less platelet activation at hypothermic temperature, and induced less platelet adhesion and aggregation on thrombogenic surfaces compared with unmodified Hb. The inhibitory effect may be derived from antiadhesive properties of Hb, antiplatelet actions of NO, and molecular barrier action of PEG.
 ...
PMID:Attenuation of hypothermia-induced platelet activation and platelet adhesion to artificial surfaces in vitro by modification of hemoglobin to carry S-nitric oxide and polyethylene glycol. 1115 32

Although the incidence of overt sequelae has traditionally been higher in patients undergoing isolated intracardiac procedures such as valve replacement or repair, recent studies show that the incidence of stroke for intracardiac procedures now approximates that for isolated coronary artery bypass grafting (CABG), in the range of 1 to 4%. In both intracardiac and extracardiac surgery, macroemboli (>200 microm in diameter) and microemboli (<40 microm in diameter) seem to be responsible for most neurologic complications. The risk of overt stroke is clearly increased in patients who undergo more complicated, combined procedures such as CABG plus valve replacement or CABG plus carotid endarterectomy. For isolated CABG, preoperative risk factors include advanced patient age, proximal aortic atherosclerosis, hypertension, previous stroke or transient ischemic attack, diabetes, and female gender. One area of controversy and current research concerns whether hypothermia is better than normothermia during cardiopulmonary bypass (CPB). Another debatable issue is whether CPB itself results in neurologic damage, owing to nonpulsatile perfusion, complement activation and the "inflammatory response," or a greater propensity for platelet activation and aggregation into microemboli in this setting. Strategies for preventing adverse neurologic outcome (new paradigms for managing intra-aortic plaque and controlling the cerebral reperfusion temperature) and for acute intervention (using specific cerebral protective agents) are under investigation. Further research into techniques for preventing or mitigating cerebral injury, particularly in high-risk patients, is clearly mandated.
 ...
PMID:A review of risk factors for adverse neurologic outcome after cardiac surgery. 1191 28

A 76-year-old woman presented with multiple brain infarctions in the right middle cerebral artery and vertebral artery area. Carotid sonography revealed a large mobile pedunculated mass in the brachiocephalic artery, which showed rapid growth despite treatment with heparin and aspirin. Graft replacement of the brachiocephalic artery was performed under selective cerebral perfusion with deep hypothermia. Histology of the resected specimen revealed aortic atherosclerotic plaque.
 ...
PMID:Graft replacement for massive mobile embolic source in brachiocephalic artery. 1898 48

Critical events during cardiopulmonary bypass (CPB) can challenge the most experienced perfusionists, anesthesiologists, and surgeons and can potentially lead to devastating outcomes. Much of the challenge of troubleshooting these events requires a key understanding of these situations and a well-defined strategy for early recognition and treatment. Adverse situations may be anticipated prior to going on CPB. Atherosclerosis is pervasive, and a high plaque burden may have implications in surgical technique modification and planning of CPB. Hematologic abnormalities such as cold agglutinins, antithrombin III deficiency, and hemoglobin S have been discussed with emphasis on managing complications arising from their altered pathophysiology. Jehovah's witness patients require appropriate techniques for cell salvage to minimize blood loss. During initiation of CPB, devastating situations leading to acute hypoperfusion and multiorgan failure may be encountered in patients undergoing surgery for aortic dissection. Massive air emboli during CPB, though rare, necessitate an urgent diagnosis to detect the source and prompt management to contain catastrophic outcomes. Gaseous microemboli remain ubiquitous and continue to be a major concern for neurocognitive impairment despite our best efforts to improve techniques and refine the CPB circuit. During maintenance of CPB, adverse events reflect inability to provide optimal perfusion and can be ascribed to CPB machine malfunction or physiological aberrations. We also discuss critical events that can occur during perfusion and the need to monitor for organ perfusion in altered physiologic states emanating from hemodilution, hypothermia, and acid-base alterations.
...
PMID:Overcoming Challenges in the Management of Critical Events During Cardiopulmonary Bypass. 2468 73

Gold standard for treatment of pathologies of the ascending aorta is still open surgery with extracorporal circulation in moderate to deep hypothermia. These procedures are associated with high morbidity and mortality, especially if performed in older patients or after previous cardiac surgery. Thoracic endovascular aortic repair (TEVAR) has become the preferred treatment option for thoracic aortic pathologies of the descending aorta even in high-risk patients with severe comorbidities resulting in reduced morbidity and mortality compared to open repair. Despite the continuous development of endograft technology an adequate arterial access still poses a relevant limitation of this treatment option accentuated in the proximal segments of the aorta. The transfemoral access may be limited due to severe kinking or arteriosclerotic plaque stenosis of femoral or iliac vessels. Furthermore, the long distance between femoral access vessels and the aortic lesion impairs device torsibility and exact deployment of the stent graft. To provide a practical alternative endovascular access to the ascending aorta, antegrade transcardiac access routes including transapical or transseptal techniques have recently gained increasing interest.
...
PMID:[Transcardiac Access Routes for Endovascular Treatment of Ascending Aortic Pathologies]. 2537 18


1 2 Next >>