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1.
PURPOSE: In patients with septic shock, the cardiac index is often increased. Maldistribution of blood flow and regional hypoperfusion has been implicated as a key factor in the pathogenesis of organ dysfunction in these patients. We have investigated the relationship between cerebral blood flow and cardiac index in patients with septic shock. MATERIALS AND METHODS: We used Doppler ultrasound techniques to investigate limb and carotid blood flow in 15 patients with septic shock and 9 nonseptic controls. RESULTS: In the nonseptic control patients, common femoral and brachial blood flow were proportional to cardiac index (r=0.73 and 0.76; P=.038 and .017, respectively) reflecting a protective redistribution of flow to more vital organs. However, this relationship was absent in patients with septic shock (r=0.23 and 0.21). Furthermore, in the septic patients but not the nonseptic controls, cerebral blood flow was correlated with the cardiac index (r=0.66, P < .05 vs r=-0.36, NS in nonseptic controls). Carotid flow was independent of mean arterial pressure, PaCO2 and PaO2 in patients with septic shock. CONCLUSIONS: These data are consistent with a loss of autoregulation of cerebral blood flow and a change in the control of limb blood flow in humans with septic shock.  相似文献   

2.
Generalized myoclonus status is common in comatose patients after cardiac resuscitation, but its prognostic value is uncertain. We studied the clinical, radiologic, and pathologic findings in 107 consecutive patients who remained comatose after cardiac resuscitation. Myoclonus status was present in 40 patients (37%). Features more prevalent in patients with myoclonus status were burst suppression on electroencephalograms, cerebral edema or cerebral infarcts on computed tomography scans, and acute ischemic neuronal change in all cortical laminae. All patients with myoclonus status died. Of 67 patients without myoclonus, 20 awakened. We conclude that myoclonus status in postanoxic coma should be considered an agonal phenomenon that indicates devastating neocortical damage. Its presence in comatose patients after cardiac arrest must strongly influence the decision to withdraw life support.  相似文献   

3.
The one-year survival, functional and cerebral capacity and patient management following out-of-hospital cardiac arrest were examined in a follow-up study of 143 prospectively identified patients discharged from a West Yorkshire hospital between January 1987 and July 1993. One-year survival was 87%; 13 of the 18 deaths were cardiac related; 89% of survivors had no further cardiac related admissions; 98% of patients surviving to one year were capable of independent daily activities. There was low utilisation of simple drug therapy: 23% of patients were discharged taking beta-blockers and 52% aspirin; 50% of patients discharged after a primary arrhythmic event were taking antiarrhythmic therapy or were given an implantable defibrillator. Irrespective of the availability of invasive cardiac facilities, there was underutilisation of investigations: only 39% of patients were seen by a cardiologist and 54% were not evaluated for ischaemic risk. Significant improvements in patient management could probably be achieved quickly without substantial increases in resources.  相似文献   

4.
Serum lipid profile is, total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL) and triglycerides and serum cardiac enzymes ie, creatinine phosphokinase (CPK), creatinine phosphokinase isoenzyme MB (CPK-MB), lactate dehydrogenase (LDH) and serum aspartate aminotransferase (AST/SGOT) levels were estimated in 50 cases of cerebrovascular accidents (CVA) consisting of 26 cases of cerebral haemorrhage and 24 cases of cerebral thrombosis. All analyses were made on day 1 and day 7. Serum cholesterol, LDL and triglycerides levels were significantly higher in CVA patients on day 1. Lipid level fell significantly on day 7 in respect to day 1. On comparing the lipid levels between cerebral haemorrhage and cerebral thrombosis, no significant difference was observed. Cardiac enzymes like CPK and CPK-MB were significantly raised whereas, AST/SGOT and LDH were marginally raised on day 1 in CVA patients. However, there was no change in cardiac enzyme levels between cerebral haemorrhage and cerebral thrombosis patients.  相似文献   

5.
Novalvular (nonrheumatic) atrial fibrillation (NVAF) is the most common cardiac condition associated with presumed embolic stroke, accounting for approximately half of the cardiogenic embolic infarctions. Of autopsied stroke patients in the Tokyo Metropolitan Geriatric Hospital, cerebral infarction was found in 75%, intracranial hemorrhage in 19%, and coexisting cerebral hemorrhage and cerebral infarction in 6%. Twenty-eight percent of the cerebral infarctions were embolic infarctions of cardiac origin, 56% of which were caused by NVAF. The incidence of cardiogenic brain embolism ranged from 6 to 23% of the ischemic strokes, and NVAF is the most frequent substrate for brain embolism. Atrial fibrillation increases in its incidence with increasing age. Chronic AF was observed in 10%, and paroxysmal AF in 7% of the autopsied elderly patients. Most of them were nonrheumatic AF. Twenty-two percent of the AF patients had large cerebral infarction, and 15% had medium-sized cortical infarction at the autopsy. NVAF is a very important cause of fatal massive cerebral infarction in the elderly. Of 56 patients with fatal massive cerebral infarction who died within 2 weeks after the strokes, 25 (45%) had embolic stroke associated with NVAF. Anticoagulant therapy prevents recurrent cerebral embolism of cardiac origin. The proper time to initiate anticoagulant therapy following cardiac brain embolism is controversial. Immediate initiation of anticoagulant therapy can reduce the early recurrence, but can result in secondary brain hemorrhage or hemorrhatic transformation. Patients with NVAF may have a lower risk of recurrence during the first 2 to 4 weeks following the initial embolic stroke compared with other cardioembolic sources. Cerebral embolism with NVAF can recur during a long period.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
The cerebral outcome of 100 consecutive patients who had cardiac valvular replacement was evaluated by comparing the results of prospective neurological examination with retrospective data. The latter showed that the overall prevalence of cerebral abnormalities was 6% (4% among survivors) up to ten days postoperatively and 9% thereafter. This contrasts with the 35% (37% among survivors) obtained by careful neurological investigations that showed five patients with residual signs one year after operation. Electroencephalographic and neuropsychological studies disclosed additional patients who had subclinical involvement. The results question the reportedly ever-falling cerebral complication values claimed particularly in retrospective studies and reflect what is missed when using rough clinical criteria. There is no justification in overlooking slight clinical or even subclinical dysfunction, since the elimination of them is the only acceptable criterion of cerebral safety in cardiac operations.  相似文献   

7.
BACKGROUND AND PURPOSE: The rationale behind early aneurysm surgery in patients with subarachnoid hemorrhage (SAH) is the prevention of rebleeding as early as possible after SAH. In addition, by clipping the aneurysm as early as possible, one can apply treatment for cerebral ischemia more vigorously (induced hypertension) without the risk of rebleeding. Hypervolemic hemodilution is now a well-accepted treatment for delayed cerebral ischemia. We compared the prospectively collected clinical data and outcome of patients admitted to the intensive care unit in the period 1977 to 1982 with those of patients admitted in the period 1989 to 1992 to measure the effect of the change in medical management procedures on patients admitted in our hospital with SAH. METHODS: We studied 348 patients admitted within 72 hours after aneurysmal SAH. Patients with negative angiography results and those in whom death appeared imminent on admission were excluded. The first group (group A) consisted of 176 consecutive patients admitted from 1977 through 1982. Maximum daily fluid intake was 1.5 to 2 L. Hyponatremia was treated with fluid restriction (<1 L/24 h). Antihypertensive treatment with diuretic agents was given if diastolic blood pressure was >110 mm Hg. Patients in the second group (172 consecutive patients; group B) were admitted from 1989 through 1992. Daily fluid intake was at least 3 L, unless cardiac failure occurred. Diuretic agents and antihypertensive medications were avoided. Cerebral ischemia was treated with vigorous plasma volume expansion under intermittent monitoring of pulmonary wedge pressure, cardiac output, and arterial blood pressure, aiming for a hematocrit of 0.29 to 0.33. Aneurysm surgery was planned for day 12. RESULTS: Patients admitted in group B had less favorable characteristics for the development of cerebral ischemia and for good outcome when compared with patients in group A. Despite this, we found a significant decrease in the frequency of delayed cerebral ischemia in patients of group B treated with tranexamic acid (P=0.00005 by log rank test) and significantly improved outcomes among patients with delayed cerebral ischemia (P=0.006 by chi2 test) and among patients with deterioration from hydrocephalus (P=0.001 by chi2 test). This resulted in a significant improvement of the overall outcome of patients in group B when compared with those in group A (P=0.006 by chi2 test). The major cause of death in group B was rebleeding (P=0.011 by chi2 test). CONCLUSIONS: We conclude that the outcome in our patients with aneurysmal SAH was improved but that rebleeding remains a major cause of death. Patient outcome can be further improved if we can increase the efficacy of preventive measures against rebleeding by performing early aneurysm surgery.  相似文献   

8.
BACKGROUND: Stroke complicates cardiac surgical procedures in a substantial number of patients. The mechanism of stroke is predominantly embolic, although hypoperfusion may play a role. The aim of this study was to determine whether radiologic appearances in this population were consistent with an embolic cause. METHODS: We reviewed computed tomographic scans and medical records in 24 patients who suffered stroke after cardiac operation. Stroke was evident at 24 hours in 19 patients (79%). Infarcts were multiple in 16 and single in 3 patients (group 1). The remaining 5 patients suffered stroke beyond 24 hours and had single infarcts on computed tomographic scan (group 2). RESULTS: In group 1, 15 patients (79%) had bilateral cerebellar infarcts, 4 (74%) had posterior cerebral artery infarcts, 10 (53%) had posterior watershed infarcts, and 11 patients (58%) had middle cerebral artery branch infarcts. The mean number of vascular territories involved was 5.1 (range, 1 to 10). Mobile atheromatous plaque was present in the ascending aorta or arch in 5 of 9 patients (56%) in group 1. In group 2, stroke occurred in close association with atrial or ventricular fibrillation in 3 of 5 patients (60%). CONCLUSIONS: In patients with radiologic evidence of infarction, perioperative strokes after cardiac operation are typically multiple, and involve the posterior parts of the brain, consistent with atheroembolization. Delayed strokes may be attributable to cardiogenic embolism.  相似文献   

9.
Three patients with left atrial myxoma presented with prominent neurologic symptoms and signs (cerebrovascular disease and/or syncope) within the past year. Two patients died because antemortem diagnosis was late or missed. One patient was successfully treated. Cardiac myxoma produces protean clinical manifestations that do not always include cardiac signs and symptoms. Neurologists may be called on for diagnostic consultation in patients who will prove to have cardiac myxoma. Unexplained transient ischemic attacks, cerebral infarction, or syncope (with possible features of seizure activity) are common neurologic manifestations of this disease. Additionally, systemic symptoms, signs, and laboratory data suggestive of collagen vascular disease or vasculitis are also often present. Echocardiography is a dependable noninvasive procedure for a confirmation of diagnosis in suspected cases.  相似文献   

10.
OBJECTIVE: To illustrate the possible role of cerebral oximetry and stroke distance as measured by Doppler ultrasound in monitoring the critically ill patient non-invasively in the emergency department. METHODS: Five critically ill patients were monitored with either cerebral oximetry or both cerebral oximetry and stroke distance (the distance travelled by blood in the aorta with each ventricular contraction), as measured by Doppler ultrasound of the aortic arch. CONCLUSIONS: Stroke distance as measured by Doppler ultrasound was a good clinical indication of reduced stroke volume and hence of cardiac output. Cerebral oximetry appears to be a useful measure of tissue hypoxia in patients in whom pulse oximetry is either unrecordable or unreliable.  相似文献   

11.
Incidence and clinical significance of cardiopulmonary complications of acute cerebral lesions are still unclear. Neurogenic pulmonary edema (NPE) is characterized as an acute, protein-rich lung edema occurring shortly after cerebral lesions associated with an acute rise of intracranial pressure. NPE is infrequently diagnosed, usually in association with head trauma. Pathophysiological mechanisms include a rise of the pulmonary vascular hydrostatic pressure either due to sympathetic innervation with pulmonary vasoconstriction or increased left-atrial pressure following systemic arterial hypertension or an increase in pulmonary capillary permeability. In contrast to NPE, cardiac complications are frequently observed, most consistently in patients with subarachnoid hemorrhage. Typical ECG changes are repolarization abnormalities, similar to those observed in coronary heart disease, and cardiac arrhythmias. The CK-MB may be slightly elevated; echocardiographic findings show a depressed left-ventricular function. Pathological examination reveals myofibrillar necrosis. Cardiac complications are explained with overactivity of the sympathetic innervation and high levels of circulating catecholamines. For adequate treatment, close cardiac monitoring is required in all patients with acute cerebral lesions.  相似文献   

12.
IR Rise  OJ Kirkeby 《Canadian Metallurgical Quarterly》1998,140(7):699-705; discussion 705-6
Reports studying the combination of low blood pressure and cerebral ischaemia are few, and it remains to be determined how cerebral circulatory insufficiency modifies the cerebral perfusion and the central haemodynamic response to blood loss. We hypothesised that occlusion of arteries to the brain modifies the cerebrovascular and cardiovascular responses to blood loss. Continuous measurements of the cerebral microcirculation with laser Doppler microprobes in the cerebral cortex were performed in anaesthetised pigs during cerebral ischaemia and haemorrhagic hypotension. The response to rapid bleeding (25% of the blood volume) was recorded during normal conditions and during cerebral ischaemia induced by bilateral occlusion of the common carotid arteries. During normal conditions haemorrhage caused insignificant decreases in cerebral microcirculation. Haemorrhage during bilateral carotid artery occlusion, however, caused significantly greater changes in cerebral microcirculation and a greater posthaemorrhagic increase in cerebrovascular resistance shortly after the blood loss. Haemorrhage during bilateral carotid artery occlusion also caused greater reductions in cardiac output and arterial pressure than similar blood loss caused during normal conditions. This study showed a disproportionate decrease in cerebral blood flow with haemorrhage during bilateral carotid occlusion, caused by an immediate increase in cerebrovascular resistance. The results suggest that even a moderate blood loss in patients with impaired cerebral circulation could be dangerous, because normal compensatory mechanisms to haemorrhage are impaired.  相似文献   

13.
STUDY OBJECTIVE: To establish the quantitative effects on the diameter of cerebral arteries following controlled changes in arterial carbon dioxide tension (PaCO2). DESIGN: Nonrandomized interventional study. SETTING: Angiography suite of a tertiary referral hospital. PATIENTS: 12 anesthetized patients suffering from a cerebral arteriovenous malformation undergoing endovascular treatment. INTERVENTION: Induced hypocapnia by hyperventilation and induced graded hypercapnia by the administration of carbon dioxide to the anesthetized patient's breathing circuit. MEASUREMENTS AND MAIN RESULTS: A digital angiography computer was used to make computerized measurements and calculations of the diameter of deep and small cortical arteries outside the vascular territory of cerebral arteriovenous malformations following controlled and standardized changes in PaCO2. Cardiovascular parameters were simultaneously measured and cardiac output (CO) calculated. No statistically significant changes in the diameter of cerebral arteries down to a size of 0.57 mm, which was the smallest artery studied, could be observed following changes in PaCO2 in the range between 28 +/- 4 mmHg and 74 +/- 4 mmHg. However, there was a 64% change in cardiac index following the above change in PaCO2. CONCLUSION: Deep cortical cerebral arteries down to a diameter of 0.57 mm seem to act merely as conductance vessels. The observed dramatic increase in CO following an increase in PaCO2 may offer an explanation for the changes in cerebral blood flow and cerebral flow velocity recorded by others and usually attributed to cerebral vasodilatation, which we were unable to demonstrate in this study.  相似文献   

14.
BACKGROUND: The indication for urgent cardiac surgical interventions in patients with active infective endocarditis has to be considered carefully following thromboembolic events, because of the high recurrence rate of such complications. In the case of brain embolisms the prognostic benefit of urgent surgery has been discussed controversially as effective anticoagulation during open heart surgery may result in secondary cerebral hemorrhages. PATIENTS AND METHODS: Between 1978 and 1993 infective endocarditis (IE) was proven in 288 consecutive and prospectively followed patients (131 females, 157 males; mean age 53.6 +/- 8.7 [9 to 81] years). To analyze potential benefits and risks of an urgent surgical intervention early after embolic cerebral infarction, cumulated survival rates were calculated for patients with and without surgical intervention with special reference to incremental risk factors and the timing of surgery. RESULTS: In 50 patients (17.4%) the clinical course was complicated by one, and in 58 patients (20.2%) by recurrent embolic events. In 80% the first embolism occurred within 33 days following the first manifestation of typical signs and symptoms of IE. 80% of recurrent events were observed within 32 days following the initial embolism. 71% of all embolic events were cerebral. In patients with cerebral embolism corroborated by computed tomography (CCT), the clinical course was complicated by intracranial hemorrhage in 12.5% while it was only 1.5% for patients without cerebral embolism. Because of a lack of therapeutic alternatives, 22 of 49 patients with recurrent embolic events, of which at least one was cerebral, underwent urgent cardiac surgery within 4 to 366 hours after the first cerebral manifestation. The cumulated survival rate of patients operated within 72 hours after the initial cerebral embolism was significantly more favorable (p < or = 0.000) than for unoperated patients or those who were operated after more than 8 days. CONCLUSION: An embolic event during IE carries a more than 50% risk of recurrence. In patients with short duration of signs and symptoms of IE and postembolic echocardiographic demonstration of persistent vegetations the probability is > 80%. At least for those patients urgent surgical intervention to remove the source of infection and embolic hazard seems to be beneficial. Surgical intervention using the heart-lung-machine should be performed within 72 hours. Such early timing results in a significant lower rate of secondary cerebral hemorrhages (p < or = 0.00) than a postponed operation. To exclude early reperfusion hemorrhage due to spontaneous thrombus fragmentation, CCT should be repeated directly preoperatively.  相似文献   

15.
OBJECTIVES: To investigate the value of extracorporeal circulatory life support (ECLS) in paediatric patients with severe Bordetella pertussis infection. DESIGN: Single case report and a review of the ECLS database. SETTING: Tertiary referral hospital paediatric intensive care unit. PATIENTS AND PARTICIPANTS: A single case report of an infant with B. pertussis infection is described. Despite receiving ECLS, this infant died from overwhelming cardiac and cerebral insults. Outcome for children receiving ECLS registered on the Extracorporeal Life Support Organization database is reviewed. MEASUREMENTS AND RESULTS: The mortality of infants receiving ECLS for B. pertussis infection is high, with only 5 survivors reported among 22 registered cases. The majority of nonsurvivors had evidence of circulatory collapse in addition to severe respiratory failure, and these patients commonly died of hypoxic-ischaemic cerebral insult. These data suggest the existence of a subgroup of patients with respiratory failure only, who may benefit from ECLS, and a larger subgroup who suffer ischaemic cardiac and cerebral insults which are unlikely to be improved by ECLS. CONCLUSIONS: The value of ECLS in patients with B. pertussis infection who present with major cardiac dysfunction is questionable. Such patients almost invariably have a poor outcome despite maximal therapy.  相似文献   

16.
The symptoms of 100 patients with chronic cardiac sinoatrial disorder were analysed. The most common presenting features were syncope in 34 cases and dizziness in 22 cases. Over three-quarters of the patients had cerebral ischaemic symptoms at some stage of the disease. Diagnostic difficulties are often encountered and are illustrated by two case histories. Although sinoatrial disorder has been described in association with neuromuscular diseases, only one such example was found in this series. The patient had a limb girdle dystrophy with cardiomyopathy and diffuse disease of the cardiac conducting system. Muscle biopsy samples taken from 11 patients with idiopathic sinoatrial disorder were normal showing no evidence of subclinical muscular disease.  相似文献   

17.
OBJECTIVE: We previously established the ability of intra-aortic balloon counterpulsation (IABC) to improve cerebral blood flow (CBF) significantly in a canine model of cerebral vasospasm. This study was performed to assess the efficacy of IABC in a patient with cardiac dysfunction and severe cerebral vasospasm that was refractory to traditional treatment measures. METHODS: We report our experience with the clinical use of IABC to treat cerebral vasospasm in a patient who suffered subarachnoid hemorrhage and concomitant myocardial infarction. Hypertensive, hypervolemic, hemodilution therapy was ineffective, and IABC was instituted. Xenon-enhanced computed tomography (Xe-CT) was utilized to obtain serial measurements of CBF with and without IABC over a 4-day period. RESULTS: IABC dramatically improved cardiac function in this patient, and Xe-CT demonstrated significant improvement in CBF with IABC. The average global CBF was 20.5 +/- 4.4 ml/100g/min before versus 34.7 +/- 3.8 ml/100g/min after IABC (p < 0.0001, paired student's t-test). The lower the CBF before IABC, the greater the improvement with IABC (correlation coefficient r = 0.83, p = 0.0007). CBF improvement ranged from 33% to 161% above baseline, average 69.3%. No complications of IABC were observed. CONCLUSIONS: This is the first report demonstrating the ability of IABC to improve CBF in a patient with vasospasm. We suggest that IABC is a rational treatment option in select patients with refractory cerebral vasospasm who do not respond to traditional treatment measures.  相似文献   

18.
Cerebral ischemic events associated with prolapsing mitral valve   总被引:1,自引:0,他引:1  
Twelve patients who had no evidence of arteriosclerotic cerebral vascular disease, lacked hypertension or coagulation defect, and had not been receiving contraceptive therapy had recurrent transient cerebral ischemic attacks (TIAs) and partial nonprogressive strokes. All had prolapsing mitral valve proved by angiocardiography. The average age was 38 years, compared with 62 years in a larger series of patients with TIA associated with arteriosclerosis. We propose that the ischemic events are related to emboli emanating from the abnormal mitral valve with or without an associated paroxysmal cardiac arrhythmia.  相似文献   

19.
BACKGROUND/AIMS: Patients with cirrhosis and ascites usually show alterations of systemic hemodynamics and are thus prone to develop arterial hypotension, which might result in cerebral hypoperfusion if cerebral autoregulation is impaired. METHODS: We evaluated cerebral autoregulation in 15 patients with cirrhosis and ascites and 15 healthy subjects by monitoring mean blood flow velocity in the middle cerebral artery and arterial pressure during supine rest and passive tilting. RESULTS: Tilt provoked a drop of arterial pressure in both groups. Control subjects had a prompt recovery of mean flow velocity and a progressive recovery of arterial pressure, so that, after 120 s, both parameters had returned to baseline: at 20 s the recovery of flow velocity was faster (p<0.01) than that of blood pressure. By contrast, patients with cirrhosis had a delayed and incomplete recovery of both parameters (p<0.01 vs healthy subjects). In eight patients, the recovery of mean flow velocity paralleled that of arterial pressure, indicating an impaired cerebral autoregulation. These patients had a worse liver function, a higher cardiac index and lower peripheral resistance. CONCLUSIONS: Cerebral autoregulation is often impaired in patients with cirrhosis and ascites. These patients can develop cerebral hypoperfusion if arterial pressure falls abruptly.  相似文献   

20.
Twelve consecutive patients requiring surgery for replacement of ascending aortic aneurysms (n = 3), ascending arch aortic aneurysms (n = 2), or type A aortic dissections (n = 7) were treated without aortic cross clamping. Retrograde cerebral perfusion (RCP) with circulatory arrest (mean RCP time: 46.0 +/- 15.9 minutes, range 20 to 65 minutes) and continuous retrograde cardioplegia (mean cardiac ischemic time: 134.4 +/- 39.7 minutes, range: 40 to 180 minutes) were employed. In the patients with aortic dissection, the intimal tear at the origin of the brachiocephalic artery (BCA) was resected completely, the aortic wall was trimmed and closed with Teflon felt. The distal anastomosis was created using an open technique. Air and debris were completely evacuated by returning blood from the cerebral vessels and femoral artery. Then the artificial graft was clamped, and cardiopulmonary bypass resumed. The proximal anastomosis was performed during rewarming. The operations were elective in seven cases, and emergent in five cases. Graft replacement of the ascending aorta was performed in ten patients (including two BCA reconstructions). The remaining two patients were treated by patch repair (n = 1), primary anastomosis (n = 1). There were no perioperative deaths. One patient had a transient neurological deficit. The distal false lumen was occluded completely in five of seven patients with aortic dissections. The other two patients had a secondary tears in the descending aorta. Thus retrograde cerebral perfusion and continuous retrograde cardioplegia without aortic cross clamping is an effective technique in the replacement of the ascending and arch aorta.  相似文献   

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