Duane E. Dede

Predictors of Cognitive Dysfunction after Major Noncardiac Surgery

Background:The authors designed a prospective longitudinal study to investigate the hypothesis that advancing age is a risk factor for postoperative cognitive dysfunction (POCD) after major noncardiac surgery and the impact of POCD on mortality in the first year after surgery. Methods:One thousand sixty-four patients aged 18 yr or older completed neuropsychological tests before surgery, at hospital discharge, and 3 months after surgery. Patients were categorized as young (18–39 yr), middle-aged (40–59 yr), or elderly (60 yr or older). At 1 yr after surgery, patients were contacted to determine their survival status. Results:At hospital discharge, POCD was present in 117 (36.6%) young, 112 (30.4%) middle-aged, and 138 (41.4%) elderly patients. There was a significant difference between all age groups and the age-matched control subjects (P < 0.001). At 3 months after surgery, POCD was present in 16 (5.7%) young, 19 (5.6%) middle-aged, and 39 (12.7%) elderly patients. At this time point, the prevalence of cognitive dysfunction was similar between age-matched controls and young and middle-aged patients but significantly higher in elderly patients compared to elderly control subjects (P < 0.001). The independent risk factors for POCD at 3 months after surgery were increasing age, lower educational level, a history of previous cerebral vascular accident with no residual impairment, and POCD at hospital discharge. Patients with POCD at hospital discharge were more likely to die in the first 3 months after surgery (P = 0.02). Likewise, patients who had POCD at both hospital discharge and 3 months after surgery were more likely to die in the first year after surgery (P = 0.02). Conclusions:Cognitive dysfunction is common in adult patients of all ages at hospital discharge after major noncardiac surgery, but only the elderly (aged 60 yr or older) are at significant risk for long-term cognitive problems. Patients with POCD are at an increased risk of death in the first year after surgery.

Molar Tooth Sign in Joubert Syndrome: Clinical, Radiologic, and Pathologic Significance:

Joubert syndrome is a rare autosomal-recessive condition characterized by early hyperpnea and apnea, developmental delay, and truncal ataxia. We previously described key ocular motor signs in Joubert syndrome and the molar tooth sign resulting from dysplasia of the isthmic segment of the brain stem, superior cerebellar peduncles, and vermis. In this study, we obtained clinical and developmental data in 61 cases, and radiologic data in 46 of these, to determine the prevalence of the molar tooth sign in a large sample, and to ensure that magnetic resonance images obtained for study were representative of the Joubert syndrome population at large. We studied the morphology of the isthmic segment of the pontomesencephalic junction, the segment of the brain stem derived from the primitive isthmus. Portions of the cerebellum analyzed included the superior cerebellar peduncles, the anterior and posterior lobes of the vermis, and the flocculonodular lobe. In one case, autopsy of the brain was performed. The average age at diagnosis was 33 months. All patients were hypo-tonic and developmentally delayed. The molar tooth sign was present in 85% of cases with 13% of these showing additional malformations. All patients without the molar tooth sign had other mimicking conditions such as neocerebellar dysgenesis, isolated vermian atrophy, cerebellar aplasia, and cystic dilation of the cisterna magna. Autopsy showed aplasia of the cerebellar vermis with dysplasia of the dentate nucleus, elongated locus coeruleus, and marked dysplasia of the caudal medulla. A better understanding of the clinical, radiologic, and pathologic features of Joubert syndrome should help uncover the genetic basis for the syndrome. (J Child Neurol 1999;14:368-376).

Neurobehavioral Development in Joubert Syndrome

Research on children with Joubert syndrome has focused on brain structural abnormalities and associated clinical symptoms. The degree of developmental delay has not been objectively reported. We investigated the neurobehavioral development of children with Joubert syndrome through neurobehavioral assessment in the largest sample to date. Thirty-two parents of children with Joubert syndrome completed the Child Development Inventory and magnetic resonance imaging (MRI) data was gathered on 17 of these children. Results indicate that 94% were severely impaired according to the Child Development Inventory, with age being positively correlated with degree of neurobehavioral impairment. The average developmental age of our sample was 19 months (63% below chronological age). Severity of illness as measured by the General Development scale of the Child Development Inventory and severity of illness as measured by MRI (overall severity rating) did not yield consistent data regarding severity of the midbrain and cerebellar malformations. Similarly, markers of abnormal cerebral development such as cortical atrophy and delayed myelination were independent of severity of illness ratings on the Child Development Inventory. The degree of developmental delay in Joubert syndrome and the severity of gross central nervous system malformations appear independent. (J Child Neurol 1998;13:391-397).

Cognition, Behavior, and Development in Joubert Syndrome

This article reports on a series of studies of children with Joubert syndrome who were examined in three investigations from 1994 through 1998. Neuropsychologic screening of 10 of 40 children showed a variety of deficits in cognition, verbal memory, visuomotor, motor, and language-related tasks. Parent report of developmental attainments revealed only 3 of 40 children functioning in the borderline range, with the rest scoring in the severely impaired range. Parent reports of behaviors revealed problems in temperament, hyperactivity, aggressiveness, and dependency, as well as problems in physical development and care that were felt to be related to their neurologic handicaps. Future directions of research with this rare disorder are suggested. (J Child Neurol 1999;14:592-596).

Cardiac Resynchronization Therapy: A Pilot Study Examining Cognitive Change in Patients Before and After Treatment

Cardiovascular patients with reduced cardiovascular output and capacity such as those with congestive heart failure (CHF) have demonstrated cognitive‐related dysfunction. The use of cardiac resynchronization therapy (CRT) is considered standard care for CHF patients who do not improve despite optimal medical therapy. Cardiac resynchronization therapy may improve neurocognitive and psychosocial functioning in patients by increasing cardiac output and cerebral perfusion.

Factors Influencing Clinical Correlates of Chronic Traumatic Encephalopathy (CTE): a Review.

Chronic traumatic encephalopathy (CTE) is a neuropathologically defined disease reportedly linked to a history of repetitive brain trauma. As such, retired collision sport athletes are likely at heightened risk for developing CTE. Researchers have described distinct pathological features of CTE as well a wide range of clinical symptom presentations, recently termed traumatic encephalopathy syndrome (TES). These clinical symptoms are highly variable, non-specific to individuals described as having CTE pathology in case reports, and are often associated with many other factors. This review describes the cognitive, emotional, and behavioral changes associated with 1) developmental and demographic factors, 2) neurodevelopmental disorders, 3) normal aging, 4) adjusting to retirement, 5) drug and alcohol abuse, 6) surgeries and anesthesia, and 7) sleep difficulties, as well as the relationship between these factors and risk for developing dementia-related neurodegenerative disease. We discuss why some professional athletes may be particularly susceptible to many of these effects and the importance of choosing appropriate controls groups when designing research protocols. We conclude that these factors should be considered as modifiers predominantly of the clinical outcomes associated with repetitive brain trauma within a broader biopsychosocial framework when interpreting and attributing symptom development, though also note potential effects on neuropathological outcomes. Importantly, this could have significant treatment implications for improving quality of life.

Continued caregiver burden: Seizure-free may not equal burden-free

While caregiver burden has been studied in various patient populations, it has not been addressed in caregivers of patients with epilepsy. This study investigated the incidence of perceived caregiver burden in caregivers of patients following surgical treatment for epilepsy, usually temporal lobectomy. The extent to which caregiver and patient variables were related to burden was explored. Data were collected on caregiver depression, caregiver coping skills, the caregivers evaluation of the patients functioning, demographic information, and the patients seizure control for 34 caregiver-patient dyads. The occurrence of significant burden in this population was comparable with the literature for other populations; however, the frequency of item endorsement varied. Regression analysis suggests that depression and patient functioning, separate from seizure control, predicted caregiver burden. The use of emotion-focused coping styles predicted depression. There were no differences in the levels of burden or depression in caregivers over time. Additional research is required to evaluate whether these relationships reflect presurgical functioning or an adjustment to the postsurgical state. Aspects of patient functioning that are important in caregiver burden also need to be clarified. This research may lead to the development of intervention strategies designed to prevent or reduce caregiver burden.

Differential effects of right hemisphere injection during the wada procedure on the primary and secondary languages in a bilingual speaker

Abstract A Wada procedure was performed on a bilingual seizure surgery candidate. Immediately after the injection of barbiturate into the right internal carotid artery the patient spontaneously switched from counting in English (the language he indicated that he used most often) to Spanish (the language he learned first). He named in Spanish spontaneously as well. After injection of the left ICA the patient exhibited a global aphasia, with no evidence for differential recovery of language as the aphasia cleared. These observations are discussed in relation to the hypothesis that a language learned later in life may be more likely to be bilaterally represented than the first language learned.