Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Midmyocardial and subendocardial pH monitoring was used as an indirect method for continuous evaluation of regional canine myocardial ischemia. Left ventricular midmyocardial pH (pHm) at 4 mm. depth was monitored in 10 dogs, under resting conditions, by means of a 5 mm. Beckman pH probe. pHm was 6.96 +/- 0.03, recorded at myocardial temperatures of 35 to 37 degrees C. Ischemia was then produced by snare occlusion of the proximal left main coronary artery for 2 minutes. pHm decreased to 6.87 +/- 0.03 (p less than 0.01) at 1 minute and 6.80 +/- 0.04 (p less than 0.005) in 2 minutes. When flow was restored, pHm returned toward normal within 2 minutes (pH 6.86 +/- 0.03) and at 5 minutes had returned to control values (pH 6.93 +/- 0.03). In another 5 dogs under similar conditions, pHm at 4 mm. and subendocardial pH (pHe at 8 mm.) were measured. Baseline pHm (6.97 +/- 0.01) and pHe (6.84 +/- 0.02) levels were significantly different (p less than 0.0005). After 2 minutes of ischemia, pHm was 6.82 +/- 0.03, whereas pHe decreased to 6.78 +/- 0.04 (p less than 0.1). Five minutes after snare release, pHe remained at 6.73 +/- 0.07; pHm (6.93 +/- 0.03) returned to control values. Both pHm (6.93 +/- 0.02) and pHe (6.84 +/- 0.09) levels were normal 15 minutes after release of the snare. The midmyocardium and subendocardium have different pH levels which can be monitored. Ischemia produces different pH patterns in these layers. pHm returns to control values within 5 minutes after 2 minutes of ischemia, whereas pHe remains depressed for at least 5 minutes. pH monitoring provides an accurate and simple method for on-line evaluation of endocardial ischemia.
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PMID:Monitoring of midmyocardial and subendocardial pH in normal and ischemic ventricles. 0 26

An original procedure of extensive bloodless hepatectomy is described in the pig. Complete vascular liver isolation with aorta clamping up to 25 min allows 60-75% bloodless hepatectomy without any portal triad dissection. Perfect hemostasis and shortening of liver ischemia is obtained with the use of a gelatin-resorcin-formaldehyde adhesive. Hemodynamic tolerance is good, and liver regeneration appears to be as fast as in minor species.
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PMID:A simplified bloodless procedure for extensive hepatectomy. Experimental study in the pig. 0 61

France transplant was founded in order to organize rationally the cadaver kidneys transport and transplantation with is omogenous compatibility tests. 2143 hemodialysis patients have been presently (1-9-72) treated in 82 dialysis center in France; 964 of them are in the France Transplant waiting list. According with recent laws, nervous function cessation is synonimous of death. That made possible, by good resuscitation techniques, to maintain a good level of circulation and oxigenation of organs. Family permit is required for this purpose. 17 medical transporttion staffs are at work in 12 France towns and cooperate with 12 typing laboratoires working with the same techniques and reagents. One permanent secretariat in Paris is always telex connected with all staffs and mantains a continuous up to date patients waiting list. 415 cadaver kidneys were transplanted, 255 in the same town and 160 trabsported from a town another. A significative rise in cold ischemia times happened recently because of the increasing number of transported kidneys.
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PMID:[Organization and results of cadaver kidney transplantation from 1969 to 1973 (author's transl)]. 0 18

Percutaneous radial artery catheterization for blood gas monitoring and continuous arterial pressure recording has become a common place procedure in the management of critically ill patients. Five patients with severe ischemia after cannulation have been encountered in the past 20 months, four of whom lost segments of one or more digits. Review of the events preceding and during radial artery cannulation allowed elucidation of the following principles: radial artery catheterization should be preceded always by a negative Allen test; the catheter should be removed after 12 to 18 hours, especially if the patient is critically ill, is hypercoagulable, or has impaired tissue perfusion; the superficial temporal artery is safer to use and permits long-term cannulation (5 to 7 days) without ill effect; and agressive approach to assessing flow and arterial reconstruction is essential if severe ischemic symptoms occur during or after radial artery catheterization. Ancillary measures, including cervicodorsal sympathetic block, intravenous low molecular weight dextran and heparin, and intra-arterial reserpine and fibrinolysin, may improve palmar circulation but should not be substituted for both noninvasive and angiographic study of arterial flow, followed by surgical restoration of flow, when indicated.
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PMID:Severe ischemia of the hand following radial artery catheterization. 0 99

A 36 year old man with panarteriitis nodosa (PAN) presented over a certain period of time meinly with gastrointestinal symptoms. He was HBsAg positive and a "reactive" hepatitis with histologically demonstrated. Arterial microaneurysms and stenoses were detected by angiography in the liver, kidney and small intestine. These findings were confirmed by autopsy. Vascular occlusions had caused infarctions of the small intestine as well as necroses and ulcerations of the large bowel. Chronic ischemia is considered as cause of the patient's malabsorption-syndrome. It is suggested, that cachexia of PAN may be partly due to malabsorption.
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PMID:[Malabsorption caused by HBsAg-positive panareteritis nodosa]. 0 47

To assess possible coronary vasoconstriction in patients with ischemic heart disease, we measured coronary vascular resistance in 12 patients with normal hearts and 12 with coronary disease before and during the initial 50 seconds of cold pressor test, a stimulus known to produce systemic vasoconstriction. Control coronary vascular resistance was similar in the two groups, and although it did not change in patients with normal vessels, it rose by 27 per cent (P less than 0.005) in the group with coronary disease during the cold pressor test. In three of 12 patients with coronary disease coronary flow actually declined despite an increase in arterial pressure; in four, angina was precipitated. Phentolamine abolished increases in arterial pressure and coronary vascular resistance during the test in three patients with coronary disease. Adrenergically mediated coronary vascular tone may be an important determinant of coronary blood flow and may contribute to ischemia in patients with coronary disease.
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PMID:Reflex increase in coronary vascular resistance in patients with ischemic heart disease. 1 May 27

Treatment of ventricular arrhythmias at the present time is difficult and requires a strong commitment on the part of the physician and the patient. Adequate documentation of the arrhythmia with continuous ECG recordings (Holter recordings), preferably for 24 hours, should be performed in each case. Exercise testing can be utilized in selected patients, but is generally inferior to the Holter technique. Underlying cardiac pathology should be searched for, utilizing echocardiography in all patients and coronary angiography and left ventriculography in patients with more severe ventricular tachycardias. Estimation of the prognostic significance of the VPBs must be made in the context of the underlying disease, and goals for treatment must be set. Treatment in all cases first requires measures to avoid known precipitating factors. If antiarrhythmic therapy is utilized, a systematic empirical trial of available agents should be undertaken, utilizing repeated Holter monitoring to document effectiveness. Serum levels of the antiarrhythmic medications should be measured in most cases. Combinations of antiarrhythmic agents can be employed if the need is great, but the agents singly are ineffective. If treatment is determined to be ineffective, it should be discontinued. Surgical techniques may be useful in cases of refractory ventricular tachycardia, and they include overdrive pacing, surgical sympathectomy, or ventricular aneurysmectomy with or without coronary bypass. Coronary bypass alone or resection of a hypokinetic but not aneurysmal area of myocardium may be successful in some cases, but the results are less predictable than when a true aneurysm is resected. Electrophysiologic studies, performed as part of the preoperative evaluation and provoking a self-perpetuating ventricular tachycardia, may permit selection of patients suitable for ventriculotomy to interrupt the re-entry pathway. At present, this must be considered experimental and is performed in only a few centers equipped for the required complex epicardial mapping. Surgery has not been shown to affect complex VPBs outside the setting of acute ischemia. Control of ventricular arrhythmias requires a highly individualistic approach with documentation of effectiveness.
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PMID:Treatment of chronic ventricular arrhythmias [proceedings]. 1 53

As shown previously, the electrical function of the brain is critically dependent on cerebral blood flow in the sense that reduction beyond an ischemic threshold of approximately 15 ml/100 gm per minute (approximately 35% of control) in the baboon leads to complete failure of the somatosensory evoked response. This study tests the hypothesis that electrical failure in ischemia may be directly associated with a massive release of intracellular K+ or with a critical degree of extracellular acidosis. By microelectrode techniques, measurements of blood flow, extracellular activity of K+ and H+ as well as evoked potential were made in the baboon neocortex. Reductions in blood flow were obtained by occlusion of the middle cerebral artery and depression beyond the ischemic threshold of electrical function achieved by a reduction of systemic blood pressure which, in the ischemic zones, changed local cerebral blood flow proportionally. Abolition of evoked response could not be explained by depolarization by release of intracellular K+, nor was it critically dependent on cortical pH. However, the massive release of intracellular K+ was by itself critically dependent on cortical blood flow and occurred at 18 greater than 6 greater than 2 ml/100 gm per minute (median with 5% confidence limits). Thus a dual threshold in ischemia for neuronal function is described, the threshold for release of K+ being clearly lower than the threshold for complete electrical failure. Further, the findings support the concept of an ischemic penumbra during which the neurons remain structurally intact but functionally inactive. That neurons can survive for some time in this state of lethargy is evidenced by the observations that an increase in rCBF, if sufficient, can restore evoked potential and normalize extracellular K+ activity as well as pH.
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PMID:Cortical evoked potential and extracellular K+ and H+ at critical levels of brain ischemia. 1 21

Fifty dog kidneys had hypothermic perfusion for 12 to 72 hours and then were transplanted. Prior to perfusion the kidneys were subjected to 15, 30, 45, and 60 minutes of warm ischemia. Fifteen minutes of warm ischemia was well tolerated (successful 72 hour preservation), but after 30 minutes successful preservation could be achieved for 24 hours only. Enzyme release and lactate formation were related to the prolongation of warm ischemia, and the highly significant concentration differences of these substances, between well functioning kidneys and those with small or no function, indicated the viability of the organ.
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PMID:Relationship between the prolongation of warm ischemia and the maximum available preservation period. 1 28

Blood flow in the vertebral artery and the upper extremity was studied in five cases of Takayasu's arteritis with subclavian steal by use of ultrasonic Doppler flowmetry and finger plethysmography. The diagnosis of subclavian steal was made by observation of flow reversal in the vertebral artery on the subclavian steal side during grip exercise and, in addition, the vertebral flow change with brachial artery occlusion. The blood flow increase of both internal cartotid and non-affected (non-subclavian steal side) vertebral arteries during a common carotid compression was almost normal in patients with Takayasu's arteritis in this study. During carotid compression on the side of the subclavian steal, ipsilateral vertebral blood flow greatly decreased, and the amplitude the ipsilateral finger plethysmogram decreased slightly or moderately. It is suggested that there are significantly important factors in suppressing sumptoms of vertebrobasilar ischemia in these patients with Takayasu's arteritis with subclavian steal. These factors are believed to be (1) good function of the circle of Willis, (2) good blood supply to the brain stem, and (3) collateral circulation to the distal subclavian artery not via the vertebral artery.
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PMID:Subclavian steal in Takayasu's arteritis. A hemodynamic study by means of ultrasonic Doppler flowmetry. 1 35


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