Postoperative Delirium and Postoperative Cognitive Dysfunction: Overlap and Divergence.

BACKGROUND: Postoperative delirium and postoperative cognitive dysfunction share risk factors and may co-occur, but their relationship is not well established. The primary goals of this study were to describe the prevalence of postoperative cognitive dysfunction and to investigate its association with in-hospital delirium. The authors hypothesized that delirium would be a significant risk factor for postoperative cognitive dysfunction during follow-up. METHODS: This study used data from an observational study of cognitive outcomes after major noncardiac surgery, the Successful Aging after Elective Surgery study. Postoperative delirium was evaluated each hospital day with confusion assessment method-based interviews supplemented by chart reviews. Postoperative cognitive dysfunction was determined using methods adapted from the International Study of Postoperative Cognitive Dysfunction. Associations between delirium and postoperative cognitive dysfunction were examined at 1, 2, and 6 months. RESULTS: One hundred thirty-four of 560 participants (24%) developed delirium during hospitalization. Slightly fewer than half (47%, 256 of 548) met the International Study of Postoperative Cognitive Dysfunction-defined threshold for postoperative cognitive dysfunction at 1 month, but this proportion decreased at 2 months (23%, 123 of 536) and 6 months (16%, 85 of 528). At each follow-up, the level of agreement between delirium and postoperative cognitive dysfunction was poor (kappa less than .08) and correlations were small (r less than .16). The relative risk of postoperative cognitive dysfunction was significantly elevated for patients with a history of postoperative delirium at 1 month (relative risk = 1.34; 95% CI, 1.07-1.67), but not 2 months (relative risk = 1.08; 95% CI, 0.72-1.64), or 6 months (relative risk = 1.21; 95% CI, 0.71-2.09). CONCLUSIONS: Delirium significantly increased the risk of postoperative cognitive dysfunction in the first postoperative month; this relationship did not hold in longer-term follow-up. At each evaluation, postoperative cognitive dysfunction was more common among patients without delirium. Postoperative delirium and postoperative cognitive dysfunction may be distinct manifestations of perioperative neurocognitive deficits.

Phase I study of low-dose metronomic temozolomide for recurrent malignant gliomas.

BACKGROUND: The treatment goal for recurrent malignant gliomas centers on disease stabilization while minimizing therapy-related side effects. Metronomic dosing of cytotoxic chemotherapy has emerged as a promising option to achieve this objective. METHODS: This phase I study was performed using metronomic temozolomide (mTMZ) at 25 or 50 mg/m2/day continuously in 42-day cycles. Correlative studies were incorporated using arterial spin labeling MRI to assess tumor blood flow, analysis of matrix metalloproteinase-2 (MMP-2) and MMP-9 activities in the cerebrospinal fluid (CSF) as surrogates for tumor angiogenesis and invasion, as well as determination of CSF soluble interleukin-2 receptor alpha (sIL-2Rα) levels as a marker of immune modulation. RESULTS: Nine subjects were enrolled and toxicity consisted of primarily grade 1 or 2 hematological and gastrointestinal side effects; only one patient had a grade 3 elevated liver enzyme level that was reversible. Tumor blood flow was variable across subjects and time, with two experiencing a transient increase before a decrease to below baseline level while one exhibited a gradual drop in blood flow over time. MMP-2 activity correlated with overall survival but not with progression free survival, while MMP-9 activity did not correlate with either outcome parameters. Baseline CSF sIL-2Rα level was inversely correlated with time from initial diagnosis to first progression, suggesting that subjects with higher sIL-2Rα may have more aggressive disease. But they lived longer when treated with mTMZ, probably due to drug-related changes in T-cell constituency. CONCLUSIONS: mTMZ possesses efficacy against recurrent malignant gliomas by altering blood flow, slowing invasion and modulating antitumor immune function.

Factors Influencing Nurses' Use of Hazardous Drug Safe-Handling Precautions.

PURPOSE/OBJECTIVES: To identify factors associated with oncology nurses' use of hazardous drug (HD) safe-handling precautions in inpatient clinical research units.
. DESIGN: Descriptive, cross-sectional.
. SETTING: The National Institutes of Health Clinical Center in Bethesda, Maryland.
. SAMPLE: 115 RNs working on high-volume HD administration units. 
. METHODS: Survey data were collected online using the Hazardous Drug Handling Questionnaire. Data were analyzed using descriptive statistics and multiple regression analysis.
. MAIN RESEARCH VARIABLES: Exposure knowledge, self-efficacy, barriers to personal protective equipment use, perceived risk, conflict of interest, interpersonal influences, workplace safety climate, and total mean HD precaution use.
. FINDINGS: Participants demonstrated high exposure knowledge, self-efficacy, perceived risk, interpersonal influences, and workplace safety climate. Participants demonstrated moderate barriers and conflict of interest. Total mean HD precaution use proved highest during HD administration and lowest for handling excreta at 48 hours. Average patients per day significantly influenced total HD precaution. CONCLUSIONS: Despite high exposure knowledge, barriers to personal protective equipment use and conflict of interest may contribute to reduced adoption of personal protective practices among oncology nurses.
. IMPLICATIONS FOR NURSING: Hospital and unit-specific factors captured by the predictor variables could contribute to institutional HD policy.

Neural substrates of vulnerability to postsurgical delirium as revealed by presurgical diffusion MRI.

Despite the significant impact of postoperative delirium on surgical outcomes and the long-term prognosis of older patients, its neural basis has not yet been clarified. In this study we investigated the impact of premorbid brain microstructural integrity, as measured by diffusion tensor imaging before surgery, on postoperative delirium incidence and severity, as well as the relationship among presurgical cognitive performance, diffusion tensor imaging abnormalities and postoperative delirium. Presurgical diffusion tensor imaging scans of 136 older (≥70 years), dementia-free subjects from the prospective Successful Aging after Elective Surgery study were analysed blind to the clinical data and delirium status. Primary outcomes were postoperative delirium incidence and severity during the hospital stay, as assessed by the Confusion Assessment Method. We measured cognition before surgery using general cognitive performance, a composite score based on a battery of neuropsychological tests. We investigated the association between presurgical diffusion tensor imaging parameters of brain microstructural integrity (i.e. fractional anisotropy, axial, mean and radial diffusivity) with postoperative delirium incidence and severity. Analyses were adjusted for the following potential confounders: age, gender, vascular comorbidity status, and general cognitive performance. Postoperative delirium occurred in 29 of 136 subjects (21%) during hospitalization. Presurgical diffusion tensor imaging abnormalities of the cerebellum, cingulum, corpus callosum, internal capsule, thalamus, basal forebrain, occipital, parietal and temporal lobes, including the hippocampus, were associated with delirium incidence and severity, after controlling for age, gender and vascular comorbidities. After further controlling for general cognitive performance, diffusion tensor imaging abnormalities of the cerebellum, hippocampus, thalamus and basal forebrain still remained associated with delirium incidence and severity. This study raises the intriguing possibility that structural dysconnectivity involving interhemispheric and fronto-thalamo-cerebellar networks, as well as microstructural changes of structures involved in limbic and memory functions predispose to delirium under the stress of surgery. While the diffusion tensor imaging abnormalities observed in the corpus callosum, cingulum, and temporal lobe likely constitute the neural substrate for the association between premorbid cognition, as measured by general cognitive performance, and postoperative delirium, the microstructural changes observed in the cerebellum, hippocampus, thalamus and basal forebrain seem to constitute a separate phenomenon that predisposes to postsurgical delirium independent of presurgical cognitive status.

Multidisciplinary family meetings in the ICU facilitate end-of-life decision making.

OBJECTIVE: The aim of this study was to assess the feasibility of establishing a multi-disciplinary family meeting (MDFM) program and the impact of such a program on the end-of-life decision making in the setting of an ICU. METHODS: During the study period MDFMs were scheduled for patients requiring mechanical ventilation for 5 or more days. The meeting followed a structured format. The pertinent details of the meeting as well as the treatment goals were recorded. RESULTS: Twenty-nine patients were enrolled in this study. Thirty-five MDFM's were held on 24 patients. A meeting could not be arranged for four patients. All meetings addressed patient's diagnosis, prognosis and goals of care. Fifteen (52%) patients (9 of whom had metastatic malignancy) had life support withdrawal and died a mean of 4.8 + 4.2 days after the first family meeting. In the remaining 9 patients (3 with localized cancer and 6 with non-cancer diagnoses), the plan following the family meeting was to continue supportive care; all of these patients survived to hospital discharge. CONCLUSIONS: Proactive MDFM's improve communication and understanding between patients' family and the treating team and facilitates end-of-life decision making.