The prevalence and prognosis of minimally elevated creatine kinase-myocardial band activity in elderly patients with syncope.

Syncope in elderly patients is often the initial manifestation of myocardial infarction (MI). Small elevations in creatine kinase-myocardial band (CK-MB) activity following syncope may represent MI, transient myocardial hypoperfusion, or insignificant background activity. To determine the prevalence and prognostic significance of minimal CK-MB elevations in elderly patients with syncope, serial serum CK-MB activities and subsequent survival experiences were determined for elderly syncope patients with and without MI, and for age-matched nonsyncopal controls. While all syncope patients with MI by specific clinical criteria had one or more abnormal CK-MB levels (greater than 5 U/L) and died within 31 months, 10% of syncope patients without MI and 10% of controls had abnormal CK-MB with no impact on mortality. Using standard clinical laboratory techniques, minimal elevation in CK-MB was found in 10% of elderly subjects with and without syncope and probably had no prognostic significance.

Impaired heart rate responses to cough and deep breathing in elderly patients with unexplained syncope.

To test the hypothesis that elderly patients with unexplained syncope have impaired autonomic control of heart rate, chronotropic responses to deep breathing and cough were studied in 12 elderly patients (85 +/- 4 years), 14 elderly control subjects (82 +/- 7 years) and 10 young subjects (26 +/- 5 years). There was no difference in resting RR interval between elderly patients with syncope and control subjects. However, the ratio of the maximum RR/minimum RR (an index of heart rate variability) during deep breathing was significantly lower in patients than in control subjects (p less than 0.005). In the minute following cough, there was no difference in initial reflex tachycardia, but subsequent rebound bradycardia was blunted in the elderly patients with syncope. The predominant impairment in elderly patients with unexplained syncope was the bradycardia component of the responses to deep breathing and cough, suggesting that these patients may have impaired parasympathetic modulation of heart rate. Although not likely to be the cause of syncope in these patients, these findings may reflect an underlying autonomic defect.

Cardiovascular and norepinephrine responses after meal consumption in elderly (older than 75 years) persons with postprandial hypotension and syncope.

Aging is associated with alterations in cardiovascular homeostasis that impair adaptation to common hypotensive stresses. Postprandial blood pressure (BP) reduction has been described in elderly subjects, but its clinical significance and pathophysiologic mechanisms are unknown. We have identified 8 elderly patients with meal-related syncope and large postprandial BP declines. To evaluate the role of sympathetic nervous system activity and insulin in the development of postprandial BP reduction, mean arterial BP, heart rate, plasma catecholamine and insulin responses to a high carbohydrate meal in these 8 syncope patients were compared with those of 7 young and 12 old nonsyncopal controls. By 60 minutes after the meal, mean arterial BP declined an average of 26 mm Hg (p = 0.001) in old syncope patients, in contrast to a decline of 9 mm Hg (p = 0.1) in elderly controls and no change in young controls. Young and old controls had significant, sustained increases in heart rate or plasma norepinephrine levels, or both, throughout the 90-minute postprandial period. However, elderly syncope patients had no significant change in heart rate and only an initial increase but subsequent sustained decrease in plasma norepinephrine levels that paralleled the marked mean arterial BP reduction. Insulin and glucose responses were not significantly correlated with mean arterial BP reduction. These findings demonstrate that compared with old and young controls, elderly patients with meal-related syncope have marked sustained declines in postprandial mean arterial BP associated with a failure to maintain compensatory norepinephrine levels and cardioacceleratory responses.

Biomedical research in the nursing home: methodological issues and subject recruitment results.

Although nursing homes are potentially important sites for geriatric research, previous reports have identified impediments to subject recruitment in this setting. We are conducting five simultaneous clinical studies in a 725-bed nursing home. Utilizing a systematic subject recruitment methodology designed to minimize patient and staff burden, we have recruited over 100 subjects. The average recruitment rate over two years from nursing home residents meeting study entry criteria was 43%. The rate was highest (81%) for a study of urinary incontinence offering direct benefit to participants, and lowest (28% and 14% respectively) for physiologic studies of vasopressin regulation and dermal vitamin D production, offering no direct benefit. Studies of syncope and dementia which benefitted groups affected by these problems but not controls, had intermediate recruitment rates (46 and 44%, respectively, P less than .002 compared to incontinence). Thus, clinically relevant projects, sensitive to the needs of the patient and institution, can recruit subjects from the nursing home.

Subarachnoid hemorrhage of unexplained cause.

During a 7-year period, we observed 58 patients with signs and symptoms of subarachnoid hemorrhage (SAH) in whom clinical and neuroradiological investigations failed to reveal a reasonable cause of the bleeding. Repeat panangiography was negative in the 2 patients with spasm. Rebleeding episodes soon after admission were rare, and the overall rebleeding rate was 3.4% (equivalent to an annual recurrence of 0.6%). In 1 case, a second extensive angiographic evaluation showed a small cerebral arteriovenous malformation, which was successfully treated surgically. On follow-up, 89% of the patients experienced a good outcome, with return to normal activities. This study confirms a good prognosis for patients with SAH of unknown cause. The necessity of performing a second angiographic study and the role of small infundibular dilations of the cerebral arteries are discussed.

Positive end-expiratory pressure in supine and sitting positions: its effects on intrathoracic and intracranial pressures.

The effects of positive end-expiratory pressure (PEEP) on central venous and intracranial (ICP) pressures were evaluated in 10 patients with posterior fossa tumors, in both supine and sitting positions. With patients in the supine position, intrathoracic PEEP-dependent venous hypertension was clearly transmitted to the intracranial compartment but without intracranial hypertension. On the contrary, with patients in the sitting position PEEP had no influence in almost half of our patients. In patients with radiological or clinical signs of increased ICP, however, the combination of head flexion and rotation with institution of PEEP caused a dangerous increase in ICP, even when the patients were in the sitting position. The need for early withdrawal of cerebrospinal fluid in these patients is stressed.

Spinal meningiomas: review of 174 operated cases.

The long-term results obtained in a series of 174 patients operated on for spinal meningiomas are critically analyzed. This series was similar to those of other authors with regard to age, sex, location of the tumors, and clinical presentation. Before surgery, about 70% of the patients were included in Groups I and II (mild neurological impairment), and about 30% of the patients were classified in Groups III and IV (significant to severe neurological impairment, up to paraplegia). Complete tumor removal was achieved in 96.5% of the patients, and surgical mortality was about 1%. Microsurgical technique, which was adopted in the last 29 cases, proved to be very effective in reducing undue damage to the spinal cord and in minimizing the postoperative neurological deficits. Of the 174 patients who underwent surgery, 156 underwent late follow-up study for an average of 15 years (2 patients died in the immediate postoperative period, and 16 patients were lost to follow-up). Twenty-nine patients died of causes unrelated to the spinal meningioma; of the remaining 126 patients, 92% were categorized in Groups I and II, and only 8% in Groups III and IV. The rate of recurrence was 6% (9 patients) among the 150 patients who had complete tumor removal, and the rate of regrowth was 17% (1 patient with anaplastic meningioma) among the 6 patients treated by subtotal removal. The early diagnosis of the disease and the use of microsurgical technique appeared as the most relevant factors for further improvement of the surgical results.

Hemangioblastomas: clinical characteristics, surgical results and immunohistochemical studies.

A surgical series of 59 patients with cerebellar or spinal cord hemangioblastomas or von Hippel-Lindau's (VHL) syndrome is analyzed. The presence of the tumor is easily detected by Computerized Tomography (CT) and Nuclear Magnetic Resonance (NMR), but angiography is still necessary for a correct surgical planning. The value of a sharp distinction among patients with single hemangioblastomas and the ones with Lindau's disease and VHL syndrome is stressed. In fact patients with single cerebellar or spinal hemangioblastomas have a good prognosis, while patients with disseminated hemangioblastomas have a rather poor outlook. Neuropathological studies with immunohistochemical techniques have been performed to identify the nature of the stromal cells of the hemangioblastomas: their origin from glial, endothelial and monociticphagocitic elements seems excluded.

Complete removal of a huge olfactory grooves meningioma in a child. Case report.

The clinical, radiological and histological findings of a huge olfactory grooves meningioma in a 14 years-old girl are described. Good result after complete removal is stressed and concerning literature is reviewed.

Computer assisted analysis of neuroradiological data in planning neurosurgical procedures.

A surgical graphic console is presented. It allows the display of multimodal images (CT, MR and digital angiography), and the identification of tridimensional outlines of structures of surgical relevance, within a surgical reference system, together with the trajectory of surgical approach.

Surgical management of giant anterior aneurysm.

BACKGROUND: Patients with intracranial anterior circulation aneurysms are subjected to surgical operation because of rupturing of the sac of the aneurysm leading to spontaneous subarachnoid hemorrhage (which occurs in most of the cases) or because of the neurological complaints caused by the mass or pulsation effect of the aneurysms against the surrounding brain structures. Direct surgical treatment of these giant aneurysms is always a challenging procedure but it makes feasible both the clipping of the neck of the aneurysm and the reduction of its mass effect. METHODS: A case series of 47 giant anterior circulation aneurysms, operated during a time span of 23 years (1972-1994) in our Institution is presented. RESULTS: In 31 cases the occlusion of the neck of the aneurysm could be achieved by applying single or multiple clips; in the remaining 16 cases the occlusion of the aneurysm was obtained by the aid of different methods. The operative mortality was 12.7%. CONCLUSIONS: Endovascular techniques for giant aneurysms occlusion are extremely useful in a combined approach. Due to their low morbidity these treatments can achieve a major role although some long term follow-up studies are still needed for a better understanding of their role.

The surgical approach to intraorbital tumors in children.

A series of 20 children operated for intraorbital tumors is presented. Ten of the patients were operated by the lateral approach, requiring orbitotomy in only 4 cases. Ten patients were operated by the medial transcranial transfrontal exposure. The surgical approach is mainly related to the location of the tumor, regardless of its malignancy. The relevance of the different neuroradiological procedures and the advantages of the different surgical approach are discussed.

Patient characteristics and pre-operative therapeutic modalities.

The International Cooperative Study on the Timing of Aneurysm Surgery included 68 participating centers from 16 different countries. Eight Italian neurosurgical units participated in the Study: Bellaria Hospital, Bologna; Neurological Institute of Milan, Milan; University Hospital, Brescia; University of Milan, Milan; University of Padova, Padova; University of Rome, Rome; Civil Hospital, Verona; and Civil Hospital, Vicenza. The overall case contribution from the Italian centers was 485 cases, 14.1% of the total study population. As compared to the other centers included in the Study, the Italian centers exhibited a higher percentage of patients with impaired consciousness; a later interval of planned surgery from SAH; frequent use of preoperative lumbar drainage, as well as antihypertensives, anticonvulsants, antifibrinolytics, steroids, diuretics and LMW dextran; and less frequent use of sedatives and narcotics. The individual Italian centers differed significantly in regard to patient characteristics and preoperative therapeutic modalities. There was a relatively high number of stuporous or comatose patients admitted to Centers 1, 7 and 8, very few admitted to Centers 5 and 6, and none admitted to Center 2. The different distribution of key prognostic factors prevents a direct comparison of the overall management results of the centers. A stratification of the patients according to a risk scale and/or a prognostic model is required for comparison of the management results.

Surgical findings and postoperative therapeutic modalities.

The 8 Italian centers participating in the International Cooperative Study on Timing of Aneurysm Surgery operated upon 68% of their patients eligible for the study. This low operative rate is mainly explained by the prevailing use of a delayed surgical policy. Only 28% of cases were operated on within 3 days of hemorrhage. Although early surgery was applied in more than 50% of patients from Centers 2, 6 and 7, most other centers operated on approximately 10% of patients within this time interval. Italian centers exhibited a wide variation in planned and actual surgery interval, with only 48% of their patients eventually operated on at the planned time. Differences from planned and actual timing of surgery were less consistent in the units performing early surgery. Preoperative conditions were different between the individual centers. The percent of patients alert at the time of surgery varied from approximately 50% in Centers 3 and 7 to 90% in Center 5. Centers 2 and 6 never operated on comatose patients and rarely stuporous patients. During surgery, induced hypotension was used in 67% of Italian patients. The brain was tight at exposure in 42% of patients from Italian centers; the difference from the other study centers was very significant (p = 0.0009). Consequently major brain resection was more frequently performed in Italy than in the other centers. Brain conditions depended mainly upon timing of surgery and preoperative grade (except for comatose patients) and varied accordingly between the individual centers. Temporary arterial occlusion was rarely used in Italian centers. Intraoperative bleeding from the aneurysm was slightly more frequent than in the other centers. The overall incidence of intraoperative complications was unremarkable. There were significant differences between the Italian and the other centers regarding the use of postoperative routines and medications. In Italian centers ventricular CSF drainage, shunt insertion, ICP monitoring, sedatives and analgesics were less frequently used; lumbar CSF drainage, anticonvulsants, steroids, and diuretics were applied more frequently. In the individual centers the major differences were in the use of antihypertensives, vasopressor agents, diuretics, hypervolemia, and low-molecular weight dextran.

Results of treatment.

Overall results of management in patients admitted to the 8 Italian centers participating in the International Cooperative Study on Timing of Aneurysm Surgery were rather unsatisfactory, with good recovery in only 42% of patients, and death in 45% of patients. As compared to the other centers included in the Study, Italian centers exhibited a significantly lower recovery rate and a significantly higher mortality rate. There were significant differences also between the individual Italian centers; independently of admission neurological status and timing of surgery, the outcome was better in centers 2 and 6 (a mortality rate under 20%) and worse in centers 1 and 8 (a mortality rate around 60%). Using prognostic factor models, higher than expected mortality rates were observed in 4 centers, and lower than expected good recovery rates in 3 centers. In Italian centers vasospasm accounted for the highest morbidity and mortality rate; the difference in mortality rate from vasospasm between Italian and other centers was very significant. Other important causes of death and disability were constituted by direct effect of the initial bleed and by recurrent hemorrhage. Patients operated on in Italian centers exhibited a good recovery in 57% of cases; the mortality was 27%. Differences from the other centers were less marked than for the overall management results. Mortality rates from vasospasm and from surgical complications were significantly higher in Italian than in the other study centers. Between the individual Italian centers, vasospasm accounted for the highest mortality rate in centers 7 and 8 (17% and 28% respectively). Postoperative pneumonia was significantly more frequent in Italian than in the other centers. In regard to timing of surgery, the differences in results between Italian and other centers were less marked when surgery was performed after 10 days from hemorrhage. In Italian centers as a whole, a delayed operation was linked with a better outcome than an early or subacute operation. The lowest recovery rate was observed in drowsy patients operated on between 4 and 10 days from the hemorrhage. Focal ischemic deficits and pneumonia were prevalent after an operation within 3 days of hemorrhage, while postoperative brain swelling was most frequent in patients operated on between 4 and 10 days from hemorrhage. The differences in results between Italian and other centers and among the individual Italian centers are widely discussed; possible explanations include inadequate modalities of treatment (especially inadequate management of vasospasm) and structural deficiencies of intensive care management in seriously ill patients.

A computer assisted toolholder to guide surgery in stereotactic space.

A computer assisted toolholder, integrated with an anatomical graphic 3-D rendering programme, is presented. Stereotactic neuroanatomical images are acquired, and the same reference system is employed to represent the position of the toolholder on the monitor. The surgeon can check the orientation of different approach trajectories, moving the toolholder in a situation of virtual reality. Angular values expressed by high precision encoders on the five joints of the toolholder modify "on line" the representation of the configuration of the toolholder within the three dimensional representation of the patient's anatomy.