Association of Intraprocedural Blood Pressure and End Tidal Carbon Dioxide with Outcome After Acute Stroke Intervention

Background

General anesthesia (GA) for acute stroke interventions may be associated with inferior functional outcomes. Our goal was to identify physiologic parameters that mediate this association.

Methods

Consecutive patients treated at our institution between August 2007 and December 2010 were identified from a prospective database. Clinical data were then extracted by retrospective chart review. Variables significantly associated with outcome in univariate analysis were also examined in multivariate analysis, controlling for well-established prespecified predictors of functional outcome.

Results

Of the 106 patients identified, 20 were excluded (17 due to the absence of 90-day mRS and 3 due to insufficient anesthetic records). Blood pressure (BP) decreased significantly after induction of GA, but there was no association between BP and outcome. End tidal carbon dioxide values (ETCO2) at 60 and 90 min, however, were significantly associated with outcomes in both univariate and multivariate analyses. Mean ETCO2 in patients with favorable outcomes (modified Rankin Scale (mRS) 0–3) was higher than in those with unfavorable outcomes (mRS 4–6): 35.2 mmHg versus 32.2 (p = 0.03) at 60 min and 34.9 versus 31.9 (p = 0.04) at 90 min. The adjusted odds ratios for poor outcomes for each 1 mmHg decrease in ETCO2 were the same: 0.76 (95 % CI 0.65–0.92; p = 0.004) at 60 min and 0.76 (95 % CI 0.61–0.93; p = 0.01) at 90 min.

Conclusions

While BP decreased significantly in patients undergoing GA for acute stroke intervention, it did not correlate with patient outcome. Decreases in ETCO2 at 30 and 60 min, however, were associated with 90-day mRS.     

Experiences of community and parental violence among HIV-positive young racial/ethnic minority men who have sex with men

Adolescents and young adults (ages 13–24) in the USA are frequently exposed to violence in their community and home. While studies have examined the prevalence and impact of violence exposure among adolescents, there is a lack of data focusing specifically on adolescent men of color who have sex with men. Eight demonstration sites funded through a Special Projects of National Significance (SPNS) Initiative recruited 363 HIV-positive racial/ethnic minority young men who have sex with men (YMSM) for a longitudinal study between 2006 and 2009. Over two-thirds of participants (83.8%) had witnessed community violence, 55.1% in the prior three months. Witnessing violence committed with a deadly weapon was significantly associated with being African-American, having ever used drugs, and drinking alcohol in the prior two weeks. Fear of violence in the community was significantly associated with depressive symptomatology, having less than a high school degree, not possessing health insurance, and site of enrollment. Having been emotionally or physically abused by a parent or caretaker was significantly associated with depressive symptomatology, attempting suicide, site of enrollment, and increased age. Witnessing violence with a deadly weapon was significantly associated with alcohol and drug use but not with high-risk sexual behaviors. As this was one of the first studies on the prevalence and correlates of violence exposure among racial/ethnic minority YMSM living with HIV, the findings can be used to inform the development of culturally appropriate resilience-focused interventions to address the aftereffects of violence exposures and help develop social support systems outside of the family.     

Having your cake and eating it too: Flexibility and power with mass univariate statistics for ERP data

ERP studies produce large spatiotemporal data sets. These rich data sets are key to enabling us to understand cognitive and neural processes. However, they also present a massive multiple comparisons problem, potentially leading to a large number of studies with false positive effects (a high Type I error rate). Standard approaches to ERP statistical analysis, which average over time windows and regions of interest, do not always control for Type I error, and their inflexibility can lead to low power to detect true effects. Mass univariate approaches offer an alternative analytic method. However, they have thus far been viewed as appropriate primarily for exploratory statistical analysis and only applicable to simple designs. Here, we present new simulation studies showing that permutation-based mass univariate tests can be employed with complex factorial designs. Most importantly, we show that mass univariate approaches provide slightly greater power than traditional spatiotemporal averaging approaches when strong a priori time windows and spatial regions are used. Moreover, their power decreases only modestly when more exploratory spatiotemporal parameters are used. We argue that mass univariate approaches are preferable to traditional spatiotemporal averaging analysis approaches for many ERP studies.     

Multiple deficit theory of schizophrenia: Incidence of markers vs. symptoms

Forty schizophrenic, 20 affective-disordered, and 40 matched normal control subjects were compared on postulated marker and symptom measures of schizophrenic deficits in: (a) affect; (b) attention; (c) proprioception; and (d) thought. The schizophrenic group was significantly more impaired on all four vulnerability markers than were the other two groups, while the schizophrenic and affective-psychotic groups showed comparable impairments on three of the psychotic symptom deficits. The incidence of multiple marker deficits was significantly greater in the schizophrenic than in the affective group. The hypothesis of independence of marker deficits was supported by the absence of any significant correlations among markers in the schizophrenic sample. The data support the theory that independent markers of schizophrenic vulnerability may potentiate schizophrenic disorders when their incidence is concurrent and at deficit levels. © 1996 John Wiley & Sons, Inc.     

Accelerated loss of lean body mass in fasting rats due to activation of pyruvate dehydrogenase by dichloroacetate

In order to test the hypothesis that increased pyruvate dehydrogenase (PDH) activity during fasting will result in accelerated loss of lean body mass, we administered sodium dichloroacetate (DCA) intraperitoneally to eight rats during the last three days of a six-day fast, while fasting control rats were given normal saline. DCA treatment resulted in an increased proportion of PDH in the active form in liver (26.5 +/- 4.3% v 13.4 +/- 0.5%, P less than 0.01). During the three-day period of administration, DCA treated rats lost more weight than control animals (42 +/- 2 v 25 +/- 1 g, P less than 0.001) and excreted more nitrogen in the urine (18.1 +/- 1.0 v 6.8 +/- 0.6 mmol/d, P less than 0.001). Calculations from nitrogen balance data suggest that 85% of the increase in weight loss of DCA treated rats over that of control animals was attributable to loss of lean body mass. We conclude that increased flux of pyruvate through the PDH reaction in the DCA-treated animals resulted in increased protein catabolism.     

Ultrasonic Cavitation-Enabled Treatment for Therapy of Hypertrophic Cardiomyopathy: Proof of Principle

Ultrasound myocardial cavitation-enabled treatment was applied to the SS-16^BN rat model of hypertrophic cardiomyopathy for proof of the principle underlying myocardial reduction therapy. A focused ultrasound transducer was targeted using 10-MHz imaging (10 S, GE Vivid 7) to the left ventricular wall of anesthetized rats in a warmed water bath. Pulse bursts of 4-MPa peak rarefactional pressure amplitude were intermittently triggered 1:8 heartbeats during a 10-min infusion of a microbubble suspension. Methylprednisolone was given to reduce initial inflammation, and Losartan was given to reduce fibrosis in the healing tissue. At 28 d post therapy, myocardial cavitation-enabled treatment significantly reduced the targeted wall thickness by 16.2% (p?<0.01) relative to shams, with myocardial strain rate and endocardial displacement reduced by 34% and 29%, respectively, which are sufficient for therapeutic treatment. Premature electrocardiogram complexes and plasma troponin measurements were found to identify optimal and suboptimal treatment cohorts and would aid in achieving the desired impact. With clinical translation, myocardial cavitation-enabled treatment should fill the need for a new non-invasive hypertrophic cardiomyopathy therapy option.