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Forty-eight children (aged 9 to 15 years) with tonic-clonic seizures were administered a neuropsychological test battery. The children with seizures of early onset (before age 5) were significantly impaired relative to the children with later onset on 8 of the 14 measures in the battery. The deficits were seen on tasks whose requirements included the repetition of a simple motor act, attention and concentration, memory, and complex problem solving. These findings emphasize the need for further research to determine the causal factors of the greater dysfunction seen in the early onset group.

The role of thermoregulatory background in the baroreceptor reflex control of the tail circulation was investigated 1) in anesthetized rats with a constant flow technique and 2) in conscious rats by measuring tail blood flow (venous occlusion plethysmography). In series I, during normothermia, systemic intravenous phenylephrine infusion increased mean arterial pressure (MAP) by 61.0 +/- 3.6 mmHg and induced a reflex decrease in tail perfusion pressure (TPP) from 105.0 +/- 6.3 to 84.2 +/- 4.4 mmHg (P less than 0.005). Hyperthermia decreased TPP to 66.5 +/- 5.1 mmHg (P less than 0.001) and abolished the TPP response to increased MAP (P greater than 0.05). Increases in MAP via systemic infusion of whole blood caused reductions in TPP during normothermia but failed to reduce TPP further during hyperthermia. Graded decreases in MAP during both normothermia and hyperthermia caused tail vasoconstriction. The increase in TPP was greater (P less than 0.025) during hyperthermia. In series II, conscious animals showed similar responses to hemorrhage. Graded decreases in MAP produced graded decreases in tail vascular conductance (TVC, ml.100 ml-1.min-1.100 mmHg-1). The slope of the TVC-MAP relationship averaged 0.011 +/- 0.003 TVC U/mmHg during normothermia and was markedly steeper (P less than 0.01) during hyperthermia (1.99 +/- 0.39 TVC U/mmHg). Thus the participation of the cutaneous vasculature of the rat in baroreceptor reflexes depends on thermal status, probably through the level of background sympathetic vasoconstrictor nerve activity.

It has been suggested that the normal aging process is characterized by a pattern of neuropsychological performance decline that implies relatively greater vulnerability of right-hemisphere functions. This hypothesis was tested in a sample of 68 volunteers aged 20-75 who were free of systemic and neurologic illness. Neuropsychologic measures of lateralized and focal function were specifically selected to eliminate systematic procedural differences among tests (e.g., timed vs. untimed, overlearned vs. unfamiliar). Inferences about the localizing significance of each measure were based on previously demonstrated double dissociation of function in lesion studies. Results suggested that declines in cerebral efficiency are not differentially lateralized. Age correlated performance changes implied bilateral reduction that was significantly more pronounced on operations associated with frontal-lobe function. Anatomic and theoretical explanations for this pattern were discussed.

A number of recent studies have emphasized the role of practice effect on test-retest changes in performance often seen on neuropsychological tests. An attempt is made to separate the influence of practice effect from other functional changes in the test-retest differences observed on the WAIS for a sample of adult epilepsy patients. Fifty-eight epilepsy patients were divided into three groups based on their WAIS test-retest score changes. Their corresponding test-retest performance on the Halstead-Reitan Battery and changes in seizure frequency were compared and analyzed. Results indicated that there was a correspondence between improvement in neuropsychological test performance, reduced seizure frequency, and improvement on the WAIS. It was concluded that test-retest changes in neuropsychological test performance reflected changes in psychological functioning of these individuals rather than the influence of practice effect. Some general issues relating to the question of disentangling the influence of practice effect from other functional changes in status were raised and discussed.

The hypothesis that alexithymia reflects a functional disconnection between the two cerebral hemispheres was examined in 25 male combat veterans with posttraumatic stress disorder (PTSD). Multiple regression analysis revealed that the efficiency of interhemispheric communication, evaluated with a tactile finger localization task, was a significant predictor of the degree of alexithymia, as measured by the Toronto Alexithymia Scale, independent of PTSD severity and IQ. The PTSD subjects without alexithymia did not differ on the finger localization task from 10 male control subjects without alexithymia. These data suggest that at least some forms of alexithymia may be mediated by an interhemispheric communication deficit.

Test-retest performance on the Wechsler Adult Intelligence Scale (WAIS) of two groups of adult epilepsy patients are presented and compared. In one group, Seizures Improved (SI) group, seizure frequency had decreased during the test-retest interval, and in the other group, Seizures Unimproved (SU) group, the number of seizures had either increased or stayed the same over the test-retest interval. The SI group showed a significant test-retest improvement on WAIS Verbal IQ, Performance IQ, and Full Scale IQ, as well as on eight of 11 WAIS subtests. In comparison, the SU group showed significant increases only on the Performance IQ and Object Assembly subtest. Furthermore, differences between the two groups were observed in the pattern of test-retest changes seen on the Performance measures relative to the Verbal measures. The results suggest that change in seizure frequency is one of the factors associated with test-retest changes in the intellectual functioning of epilepsy patients.

Measurement of minimal vascular resistance has proved useful in quantifying structural changes in regional circulations. Accurate measurement of minimal vascular resistance requires full relaxation of all resistance vessels within the region under examination. The usual procedure in humans involves the measurement of maximal forearm blood-flow following 6-10 min of forearm ischaemia. We conducted this study to find whether forearm skin was fully vasodilated by this procedure. Peak forearm blood-flow was measured by plethysmography in six healthy subjects following 10 min of ischaemia while the arm was at a neutral temperature (33 degrees C) and while the arm was locally warmed to 42 degrees C. Peak reactive hyperaemia blood-flow was significantly elevated by local heating (P less than 0.001) to 79.6 ml 100 ml-1 min-1 from a value of 50.2 ml 100 ml-1 min-1 during normothermia. Peak reactive hyperaemia blood-flow in the contralateral unheated forearm showed no significant change between the two periods of ischaemia (P greater than 0.05). These findings were confirmed in four subjects by laser Doppler velocimetry, which gives a linear index of skin blood-flow. In normothermic conditions, this index rose to 0.89 V following 10 min of ischaemia and to 1.26 V with local warming to 42 degrees C (P less than 0.001). Ischaemia plus local warming did not cause a further significant rise in this index of skin blood-flow (1.35 V, P greater than 0.05). These data suggest that 10 min of ischaemia during normothermia is insufficient to relax fully cutaneous resistance vessels and that maximal forearm blood-flow is underestimated by this procedure.

Clinical indicators were developed and used to assess the quality of patient care resulting from the system of shared responsibility between emergency department (ED) and radiology department faculty physicians for interpretation of ED roentgenograms. The first indicator--all discrepancies in roentgenogram interpretation between ED and radiology department faculty--measured an overall discrepancy rate of 3.3% (776 films). Three hundred fifty-two apparent discrepancies were not related to the accuracy with which ED faculty interpreted films, resulting in a revised overall discrepancy rate of 1.8%. The second indicator--undesirable patient care outcomes as a result of delayed accurate radiological diagnosis--measured an occurrence rate of 0 after clinical reevaluation of more than 99% of patients within 24 hours of initial ED evaluation. Aspects of the development and use of clinical indicators are discussed in relationship to the broader monitoring and evaluating process necessary for the continuous improvement of patient care.

To find whether sweat rate (SR) and forearm skin blood flow ( SkBF ) were reflexly affected by skin temperature (Tsk) we used water-perfused suits to rapidly elevate Tsk during exercise. With this elevation in Tsk, there was a period of little net change in esophageal temperature (Tes) but marked responses in SR and SkBF . During this period a rise in Tsk of 4.2 +/- 0.3 degrees C was associated with an increase in SR of 0.44 +/- 0.09 mg X cm-2 X min-1 and an increase in SkBF of 3.27 +/- 0.42 ml X 100 ml-1 X min-1. Multiple linear regression analysis as well as comparison with control studies in which Tsk was kept cool also reveal a consistent role for Tsk in the reflex regulation of SR and SkBF . Responses in SR and FBF were much more marked at levels of Tsk below 33 degrees C. Below a Tsk of 33 degrees C, SR rose 0.30 +/- 0.06 mg X cm-2 X min-1 per degrees C rise in Tsk, whereas above 33 degrees SR rose only 0.05 +/- 0.01 mg X cm2 X min per degrees C. FBF rose 2.81 +/- 0.60 and 0.77 +/- 0.18 ml X 100 ml-1 X min-1 per degrees C rise in Tsk at the lower and upper ranges of Tsk, respectively.

This study examined how local forearm temperature (Tloc) affects the responsiveness of the cutaneous vasculature to a reflex drive for vasoconstriction. We observed responses in forearm blood flow (FBF) and arterial blood pressure to a 5-min bout of supine leg exercise of moderate intensity (125-175 W) after the forearm had been locally warmed to 36, 38, 40, or 42 degrees C for 48 min. With exercise, FBF fell by 1.82 +/- 0.23, 4.06 +/- 0.58, and 3.64 +/- 1.48 ml X 100 ml-1 X min-1 at 36, 38, and 40 degrees C, respectively, and rose by 2.16 +/- 0.57 ml X 100 ml X min-1 at a Tloc of 42 degrees C (mean +/- SE). Forearm vascular conductance (FVC) fell with the onset of exercise by averages of 2.77 +/- 0.57, 7.02 +/- 0.51, 5.36 +/- 0.85, and 4.17 +/- 0.79 ml X 100 ml-1 X min-1 X 100 mmHg-1 at 36, 38, 40, and 42 degrees C, respectively. Second-order polynomial regression analysis indicated that the reductions in FVC were greatest near a Tloc of 39 degrees C and that at a Tloc of 40 or 42 degrees C the cutaneous vasoconstrictor response to the onset of exercise is attenuated. Although elevated Tloc can be used to increase base-line FBF levels to make cutaneous vasoconstrictor responses more obvious, the direct effects of Tloc on this response must also be considered. We conclude that the optimum Tloc for observing reflex cutaneous vasoconstriction is near 39 degrees C.

Neuropsychological performance data from 106 children with epilepsy were evaluated to determine the effects of seizure type and age of onset. The performance of children with partial seizures (N = 49) was similar to that of children with generalized seizures (N = 57). Only one of 13 tests showed a significant difference between groups, with children with partial seizures performing better on that test. The effects of age of onset were also similar in the two seizure groups. Children whose seizures began before the age of 5 years performed significantly worse than children whose seizures began later on four measures (Verbal IQ, Performance IQ, Trails A, and Trails B) and performed more poorly, but not significantly so, on the other nine measures in the battery. A breakdown of the partial group into simple partial, complex partial, and secondarily generalized partial seizure groups found a significant difference between the groups on only one variable, but there were suggestions in the data that the performance of the partial secondarily generalized group was worse than the other two groups. These results indicate that variables associated with an early onset of seizures, regardless of type, place a child at risk for cognitive dysfunction.

In awake dogs with atrioventricular block, we examined the responses in total peripheral resistance and atrial rate to square-wave changes in mean arterial pressure or cardiac output. We compared the responses 2-3 min after a step change with the responses 19-20 min after a step. With resetting of arterial pressure control, the compensatory responses should decrease as the baroreceptors reset to the prevailing pressure. With step changes in mean arterial pressure or cardiac output, the responses in both peripheral resistance and atrial rate increased from minutes 2-3 to minutes 19-20. The responses in peripheral resistance also increased in animals studied after bilateral vagal block. All of the above changes were significant in the majority of cases. In another experiment, the animals were "conditioned" by 20 min at imposed high or low pressure. When control was returned to the animal after conditioning at high pressure, arterial pressure was not significantly different (P greater than 0.05) from the initial control levels. When control was returned after conditioning at low pressure, arterial pressure was significantly greater (P less than 0.05) than during the initial control period. These results indicate an absence of resetting of the entire arterial pressure control system.

The clinical and laboratory findings in a patient with uncontrolled gastrointestinal bleeding secondary to combined hemostatic defects (von Willebrand's disease and hemorrhagic telangiectasia) are described. Evidence for von Willebrand's disease was found in five family members, but no other affected relative was found to have hemorrhagic telangiectasia. Complete assestivity, factor VIII antigen and von Willebrand factor levels. The patient described also was evaluated for her response to transfusion utilizing these same measurements. Previous reports of the coexistence of hemostatic defects with hereditary hemorrhagic telangiectasia are reviewed. The importance of complete hemostatic evaluation of patients with mucocutaneous bleeding is stressed in light or current knowledge of the diagnostic specificity of available laboratory tests.

The intellectual performance of 350 patients with seizures was examined. Seizures were classified according to the revised International Classification of Epileptic Seizures as partial (simple or complex), generalized, or partial secondarily generalized. Performance on the Wechsler Intelligence subtests served to measure intellectual ability. Patients with partial seizures performed better on Digit Span, Digit Symbol, Block Design, and Object Assembly than those with either generalized or partial secondarily generalized seizures. These subtests are functionally associated with abilities such as attention, visuospatial problem-solving, and sequencing ability.

In light of anatomical evidence that the corpus callosum does not become fully mature until about age 10, the present study attempted to find evidence of a developmental increase in the efficiency with which information is transferred between the 2 hands (hemispheres). Children were tested at ages 5, 7, and 9 on a battery of 4 tasks which measured the interhemispheric transfer of information necessary to (1) perform a simple size discrimination, (2) reproduce a temporal pattern, (3) reproduce a linear motor movement, and (4) reconstruct a 2-dimensional spatial pattern. All tasks were performed without visual guidance and utilized unilateral tactual and/or kinesthetic input and a 1-handed response. 2 tasks--the motor movement task and the spatial pattern task--showed evidence of a developmental increase in interhemispheric transfer, but the developmental pattern seen on these 2 tasks differed. Possible reasons for the between-task differences are discussed as well as their possible developmental implications.

The purpose of this investigation was to delineate the mode of efferent neural control mediating rat tail vasodilation during body heating. Tail blood flow (venous occlusion plethysmography), tail skin temperature over the ventral vascular bundle, and arterial pressure were measured in Sprague-Dawley rats anesthetized with pentobarbital sodium (45 mg/kg). Three protocols were followed: anesthesia of the lumbar sympathetic chain, bilateral lumbar sympathectomy, and sympathetic nerve stimulation during varying degrees of alpha-adrenergic receptor blockade. Mean tail blood flow and tail vascular conductance (TVC) during body heating were 40.3 +/- 8.7 ml X 100 ml-1 X min-1 and 39.2 +/- 9.2 ml X 100 ml-1 X min-1 X 100 mmHg-1, respectively. Interruption of sympathetic nerve activity by sympathetic nerve anesthetization or sympathectomy during heat stress caused a nonsignificant increase in TVC to 112.7 +/- 1.8 and 121.12 +/- 6.3%, respectively, of the values achieved with body heating. Sympathectomy performed in normothermic animals that had recovered from prior heating caused an increase in TVC to 128.4 +/- 14.0% of the levels achieved during the previous heating period. In addition, sympathetic nerve stimulation after complete alpha-adrenergic receptor blockade failed to produce a vasodilation [control TVC = 10.2 +/- 3.9 vs. TVC during nerve stimulation = 10.4 +/- 3.9 (P greater than 0.05)]. It is concluded that the increase in TVC during body heating occurs solely via a reduction in vasoconstrictor nerve activity.

Considerable discussion concerning the fate of the internship within the postgraduate period of physicians' training has taken place. Some specialty boards have eliminated the requirement of a free-standing internship. However, no replicable study findings defining exactly what an intern does have been reported in the literature. By analyzing the patient experiences that a straight medical intern encountered, the authors of this paper illustrate what many persons have previously said: the traditional internship is unrealistic with respect to the practice of medicine. The intern described here assumed care for acutely ill persons to the exclusion of all other responsibilities. The importance of objective and reproducible record-keeping is emphasized for both established and newly created programs in the primary care specialties.

We studied reflex responses to pressure changes at arterial and cardiopulmonary baroreceptors in five awake dogs with atrioventricular block before and after baroreceptor denervation. We changed ventricular pacing rate and blood volume to vary cardiac output and arterial (MAP) and central venous pressure (CVP). We determined peripheral resistance (TPR) and atrial rate (HRA) as responses. In the intact animal, regression analysis showed an average relationship across dogs of TPR = 169-0.69 MAP-1.952 CVP + error. Correlation (r) between observed and predicted TPR was 0.83. For HRA, regression indicated HRA = 291.66-2.319 MAP + 8.144 CVP + error (r = 0.899). TPR and MAP are percent of control at 90 beats/min; CVP is in mmHg; HRA, in beats/min. Although its coefficient is smaller, MAP explains approximately 69% of the variation in TPR. After arterial baroreceptor denervation, effects of MAP on TPR were insignificant and the coefficient for CVP increased. Subsequent vagal block eliminated all reflex responses. Effects from the two receptor sites sum linearly. They act cooperatively with changes in blood volume, but oppose one another with cardiac output changes.

Disasters involving multiple casualties or the injury or illness of a prominent person can push the hospital into the public relations spotlight. How the physician who is cast into the role of spokesman responds to the press can have significant ramifications for the hospital, the patient, and the public as well.

This study examines the control of arterial blood pressure in conscious, instrumented dogs with atrioventricular block before and greater than or equal to 9 days after carotid sinus baroreceptor denervation. Strength of reflex control of blood pressure was quantitated by measuring the changes in peripheral resistance and atrial rate after square wave changes in cardiac output. Surprisingly, nine or more days after carotid denervation, the strength of baroreflex control of peripheral resistance and atrial rate were not different (P greater than 0.05) from the values before denervation. This was not due to a change in the base-line levels of arterial pressure, atrial rate, cardiac output, or peripheral resistance. Bilateral vagal block after carotid denervation removed reflex effects from remaining baroreceptors and virtually eliminated changes in peripheral resistance in response to changes in arterial pressure. Therefore, the compensatory responses observed after carotid denervation were mediated by the remaining baroreceptors. Thus, after chronic carotid sinus denervation, there is no decrease in the strength of baroreflex control of peripheral resistance or heart rate.