Systolic blood pressure and short-term mortality in the emergency department and prehospital setting: a hospital-based cohort study

IntroductionSystolic blood pressure is a widely used tool to assess circulatory function in acutely ill patients. The systolic blood pressure limit where a given patient should be considered hypotensive is the subject of debate and recent studies have advocated higher systolic blood pressure thresholds than the traditional 90 mmHg. The aim of this study was to identify the best performing systolic blood pressure thresholds with regards to predicting 7-day mortality and to evaluate the applicability of these in the emergency department as well as in the prehospital setting.MethodsA retrospective, hospital-based cohort study was performed at Odense University Hospital that included all adult patients in the emergency department between 1995 and 2011, all patients transported to the emergency department in ambulances in the period 2012 to 2013, and all patients serviced by the physician-staffed mobile emergency care unit (MECU) in Odense between 2007 and 2013. We used the first recorded systolic blood pressure and the main outcome was 7-day mortality. Best performing thresholds were identified with methods based on receiver operating characteristics (ROC) and multivariate regression. The performance of systolic blood pressure thresholds was evaluated with standard summary statistics for diagnostic tests.ResultsSeven-day mortality rates varied from 1.8 % (95 % CI (1.7, 1.9)) of 112,727 patients in the emergency department to 2.2 % (95 % CI (2.0, 2.5)) of 15,862 patients in the ambulance and 5.7 % (95 % CI (5.3, 6.2)) of 12,270 patients in the mobile emergency care units. Best performing thresholds ranged from 95 to 119 mmHg in the emergency department, 103 to 120 mmHg in the ambulance, and 101 to 115 mmHg in the MECU but area under the ROC curve indicated poor overall discriminatory performance of SBP thresholds in all cohorts.ConclusionsSystolic blood pressure alone is not sufficient to identify patients at risk regardless of the defined threshold for hypotension. If, however, a threshold is to be defined, a systolic blood pressure threshold of 100 to 110 mmHg is probably more relevant than the traditional 90 mmHg.

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Electrocortical evidence for rapid allocation of attention to threat in the dot-probe task

Threatening stimuli have been shown to preferentially capture attention using a range of tasks and measures. However, attentional bias to threat has not typically been found in unselected individuals using behavioral measures in the dot-probe task, one of the most common ways of examining attention to threat. The present study leveraged event-related potentials (ERPs) in conjunction with behavioral measures in the dot-probe task to examine whether more direct measures of attention might reveal an attentional bias to threat in unselected individuals. As in previous dot-probe studies, we found no evidence of an attentional bias to threat using reaction time; additionally, this measure exhibited poor internal reliability. In contrast, ERPs revealed an initial shift of attention to threat-related stimuli, reflected by the N2pc, which showed moderate internal reliability. However, there was no evidence of sustained engagement with the threat-related stimuli, as measured by the late positive potential (LPP). Together, these results demonstrate that unselected individuals do initially allocate attention to threat in the dot-probe task, and further, that this bias is better characterized by neural measures of attention than traditional behavioral measures. These results have implications for the study of attention to threat in both unselected and anxious populations.     

Adult sexual abuse is associated with elevated neurohormone levels among women with PTSD due to childhood sexual abuse

Posttraumatic stress disorder (PTSD) has been associated with reduced, similar, or increased urinary cortisol levels. The authors identified a factor that might contribute to such variability when they obtained 24-hour urinary neurohormone profiles on 69 women with PTSD due to childhood sexual abuse. Half (n = 35) had subsequently experienced adult sexual abuse (ASA) while the other half (n = 34) had not. The ASA group had significantly elevated urinary cortisol, norepinephrine and dopamine levels in comparison to the non-ASA group. Neither a history of childhood or adult physical abuse nor other variables contributed to this finding. The results suggest that the psychobiological consequences of exposure to the same traumatic event may differ as a result of an interaction between age and the composite history of trauma exposure.     

Does C‐reactive protein independently predict mortality in adult community‐acquired bacteremia patients with known sepsis severity?

We evaluated whether sepsis severity and C‐reactive protein (CRP) level on admission prognostically corroborated or annulled each other in adult patients with incident community‐acquired bacteremia (Funen, Denmark, 2000–2008). We used logistic regression and area under the receiver operating characteristic curve (AUC) to evaluate 30‐day mortality in four models: (i) age, gender, comorbidity, bacteria, and ward. (ii) Model 1 and sepsis severity. (iii) Model 1 and CRP. (iv) Model 1, sepsis severity, and CRP. Altogether, 416 of 1999 patients died within 30 days. CRP independently predicted 30‐day mortality [Model 4, odds ratio (95% CIs) for 100 mg/L: 1.16 (1.06–1.27)], but it did not contribute to the AUC (Model 2 vs Model 4: p = 0.31). In the 963 non‐severe sepsis patients, CRP independently predicted 30‐day mortality [Model 4: 1.42 (1.20–1.69)] and it increased the AUC (Model 2 vs Model 4: p = 0.06), thus CRP contributed as much as sepsis severity to prognosis.     

Electrocortical and ocular indices of attention to fearful and neutral faces presented under high and low working memory load

Working memory load reduces the late positive potential (LPP), consistent with the notion that functional activation of the DLPFC attenuates neural indices of sustained attention. Visual attention also modulates the LPP. In the present study, we sought to determine whether working memory load might exert its influence on ERPs by reducing fixations to arousing picture regions. We simultaneously recorded eye-tracking and EEG while participants performed a working memory task interspersed with the presentation of task-irrelevant fearful and neutral faces. As expected, fearful compared to neutral faces elicited larger N170 and LPP amplitudes; in addition, working memory load reduced the N170 and the LPP. Participants made more fixations to arousing regions of neutral faces and faces presented under high working memory load. Therefore, working memory load did not induce avoidance of arousing picture regions and visual attention cannot explain load effects on the N170 and LPP.