Perioperative cardiac events in patients undergoing noncardiac surgery: a review of the magnitude of the problem, the pathophysiology of the events and methods to estimate and communicate risk

THIS IS THE FIRST OF 2 ARTICLES EVALUATING cardiac events in patients undergoing noncardiac surgery. In this article, we review the magnitude of the problem, the pathophysiology of these events, approaches to risk assessment and communication of risk. The number of patients undergoing noncardiac surgery worldwide is growing, and annually 500 000 to 900 000 of these patients experience perioperative cardiac death, nonfatal myocardial infarction (MI) or nonfatal cardiac arrest. Although the evidence is limited, a substantial proportion of fatal perioperative MIs may not share the same pathophysiology as nonoperative MIs. A clearer understanding of the pathophysiology is needed to direct future research evaluating prophylactic, acute and long-term interventions. Researchers have developed tools to facilitate the estimation of perioperative cardiac risk. Studies suggest that the Lee index is the most accurate generic perioperative cardiac risk index. The limitations of the studies evaluating the ability of noninvasive cardiac tests to predict perioperative cardiac risk reveals considerable uncertainty as to the role of these popular tests. Similarly, there is uncertainty as to the predictive accuracy of the American College of Cardiology / American Heart Association algorithm for cardiac risk assessment. Patients are likely to benefit from improved estimation and communication of cardiac risk because the majority of noncardiac surgeries are elective and accurate risk estimation is important to allow informed patient and physician decision-making.     

Measurement of maximum variability within event related potentials in schizophrenia.

One limitation of averaging individual late component event related potential (ERP) responses is that a single average ERP cannot reflect the variability of responses from epoch to epoch. In this article, we describe a method to quantify this variability and determine if any part of the overall ERP reflects a maximum variance through the use of response variance curves. We then apply this method to one disorder, schizophrenia, in which variability of information processing is hypothesized to underlie aspects of the symptomatology. Response variance curves in a group of unmedicated schizophrenic patients reveal systematic differences, maximal between 190 and 250 ms, compared with those in a group of medicated schizophrenic patients and normal control subjects.     

Resilience in Families with Children and Adult Members with Intellectual Disabilities: Tracing Elements of A Psycho‐Social Model

Aim This paper seeks to illumine how families with children and adult members with intellectual disabilities manage to manifest a buoyant and durable capacity over time. It is therefore concerned centrally with the idea of resilience. Method Drawing from diverse theoretical literatures from child development and protection and gerontology, the paper begins with a review of constructions of resilience. In an attempt to assess where there seems to be support for resilience in families, the core of the paper tests empirical evidence about positive experiences of families supporting children and adults with intellectual disabilities against the theoretical literature on resilience. Result and Conclusions The findings are used to suggest conditions under which resilience is produced and maintained, and to identify emergent elements of a psycho‐social model of resilience in families with children and adult members with intellectual disabilities.     

Metabolic fate of valproic acid in the rhesus monkey. Formation of a toxic metabolite, 2-n-propyl-4-pentenoic acid

The metabolic fate of an iv bolus dose (13.5 mg kg-1) of valproic acid (VPA) was studied in adult male rhesus monkeys. Renal excretion proved to be the major route of elimination of the drug and a total of 17 metabolites, accounting collectively for some 82% of the administered dose, were identified in urine by GC-MS techniques. Many of these metabolites were present largely in the form of glucuronide conjugates, as was VPA itself. The principal pathways of VPA biotransformation were, in order of decreasing quantitative importance, ester glucuronide formation, omega-oxidation, beta-oxidation and (omega-1)-hydroxylation. In addition, three mono-unsaturated metabolites, identified as (E)-delta 2-, (E)-delta 3-, and delta 4-VPA, were detected in both plasma and urine. Quantitative analysis of these unsaturated VPA metabolites indicated that the delta 4 olefin, which is known to be a potent hepatotoxic agent, was the predominant isomer of the group.