Behavioral analysis of predictive saccade tracking as studied by countermanding

The ability to make predictive saccadic eye movements is dependent on neural signals that anticipate the onset of a visual target. We used a novel paradigm—based on the saccade-countermanding task—as a tool to investigate rhythm saccade pacing and to provide information on the mechanisms of predictive timing. In particular, we examined the ability of normal subjects to stop a sequence of periodically paced eye movements when cued by a stop signal that was presented at different times with respect to the last target of the sequence (stop signal delay, SSD). The timing of the stop signal affected the ability to stop the saccadic sequence (make a saccade to a central target rather than to the peripheral alternating targets) in different ways, depending on the preceding tracking behavior. For the same SSD, subjects cancelled fewer trials during predictive tracking (promoted by tracking targets alternating at a fast pacing rate, 1.0 Hz) than during reactive tracking (tracking alternating targets at a low pacing rate, 0.2 Hz). In addition, on non-canceled trials, there was an increase in the delay of the corrective saccade to the central target with increasing SSD for pacing at 0.2 Hz, but the timing of the corrective saccade remained near constant for 1.0 Hz pacing. In examining the timing between movements, we estimate that the repetitive GO process that drives the saccades during predictive tracking begins earlier and has a shorter duration than the repetitive GO process during reactive tracking. These behavioral results provide further insight into the initiation process of predictive responses. In particular, the reduced reaction time and the corresponding short duration of the predictive process may result from a faster accumulation of neuronal discharge to a relatively fixed threshold.     

An oral hygiene brochure for your implant overdenture patients

Although there may not be a direct association between oral hygiene and implant failure, oral hygiene must be maintained around implants in the edentulous mouth. Bacterial plaque on dentures can act as a reservoir for pathogens that cause respiratory disease. Unfortunately, many edentulous patients have poor oral hygiene. In this article, we describe the development of a brochure to educate patients wearing mandibular overdentures supported by 2 implants as a supplement to the dentist"s verbal instructions. Dental literature and several specialists were consulted during preparation of the brochure, which contains photographs accompanying oral hygiene instructions. It was sent to 25 participants who were subsequently called and questioned regarding its content and their oral hygiene habits. The 24 respondents found the brochure useful; most reported that they would keep the brochure for future reference and that they learned something new about how to maintain their implants properly. No one found the brochure too long or unclear. Most participants read the brochure entirely, rather than skimming it. The brochure is available to all clinicians who wish to incorporate this tool into their implant overdenture therapeutic approach.     

Predictors of mortality and cost among surgical patients requiring rapid response team activation

BackgroundPrior studies of rapid response team (RRT) implementation for surgical patients have demonstrated mixed results with respect to reductions in poor outcomes. The aim of this study was to identify predictors of in-hospital mortality and hospital costs among surgical inpatients requiring RRT activation.MethodsWe analyzed data prospectively collected from May 2012 to May 2016 at The Ottawa Hospital. We included patients who were at least 18 years of age, who were admitted to hospital, who received either preoperative or postoperative care, and and who required RRT activation. We created a multivariable logistic regression model to describe mortality predictors and a multivariable generalized linear model to describe cost predictors.ResultsWe included 1507 patients. The in-hospital mortality rate was 15.9%. The patient-related factors most strongly associated with mortality included an Elixhauser Comorbidity Index score of 20 or higher (odds ratio [OR] 3.60, 95% confidence interval [CI] 1.96–6.60) and care designations excluding admission to the intensive care unit and cardiopulmonary resuscitation (OR 3.52, 95% CI 2.25–5.52). The strongest surgical predictors included neurosurgical admission (OR 2.09, 95% CI 1.17–3.75), emergent surgery (OR 2.04, 95% CI 1.37–3.03) and occurrence of 2 or more operations (OR 1.73, 95% CI 1.21–2.46). Among RRT factors, occurrence of 2 or more RRT assessments (OR 2.01, 95% CI 1.44–2.80) conferred the highest mortality. Increased cost was strongly associated with admitting service, multiple surgeries, multiple RRT assessments and medical comorbidity.ConclusionRRT activation among surgical inpatients identifies a population at high risk of death. We identified several predictors of mortality and cost, which represent opportunities for future quality improvement and patient safety initiatives.     

Time to Administration of Antibiotics among Inpatients with Severe Sepsis or Septic Shock

Background

Current evidence suggests that administration of appropriate antibiotic therapy within 1 h after the onset of hypotension significantly improves mortality rates among patients with severe sepsis and septic shock.

Objectives:

To determine the interval from recognition of severe sepsis or septic shock in inpatients to initial administration of antibiotic and to assess institutional compliance with the Surviving Sepsis Campaign’s recommendation for early antibiotic therapy.

Methods:

A 6-month retrospective chart analysis was conducted to determine the interval from documented onset of hypotension to initial administration of antibiotic for patients with severe sepsis or septic shock. Patients who were admitted to a general medicine ward, a surgery ward, or the intensive care unit (ICU) of a 475-bed university-affiliated hospital and who met the criteria for severe sepsis or septic shock were eligible for inclusion. Patients who received antibiotics before meeting the criteria for severe sepsis or septic shock were excluded.

Results:

Charts for 100 patients with severe sepsis or septic shock were reviewed. The mean age was 69.0 years (standard deviation 18.7 years), and 56% were men. The median interval from onset of severe sepsis or septic shock to administration of antibiotic was 4.00 h (interquartile range [IQR] 1.80–6.45 h). The median interval from the time a physician ordered an antibiotic to administration of the drug was 1.28 h (IQR 0.57–3.05 h). The interval between ordering and administration differed significantly for patients on the wards (5.67 h), those with onset in the ICU (4.00 h), and those with onset in the emergency department (3.28 h) (p = 0.039). The overall survival rate was 56%.

Conclusion:

At the study hospital, the interval from onset of severe sepsis or septic shock to initial administration of antibiotic to inpatients exceeded the 1-h period recommended by the Surviving Sepsis Campaign. These results will be used as a baseline for future quality assurance and improvement initiatives aimed at minimizing the time to antibiotic administration for this group of patients, who are at high risk of death.     

Risk factors for avascular bone necrosis in systemic lupus erythematosus

OBJECTIVE: To study the predictive factors for avascular necrosis (AVN) of bone in patients with systemic lupus erythematosus (SLE). METHOD: The records of 38 SLE patients who developed clinically apparent AVN during the course of their disease were reviewed. Information on clinical presentation, corticosteroid usage and autoantibody profiles was obtained, and comparison was made between these patients and 143 consecutive control SLE patients who did not have AVN. RESULTS: The point prevalence of AVN in our SLE population was 12%. Patients with AVN, when compared with controls, had a significantly higher incidence of neurological disease (39% vs 14%; P < 0.001) and Cushingoid body habitus after steroid treatment (79% vs 53%; P = 0.004). The highest cumulative prednisolone dose in 1 and 4 months was significantly higher in the AVN group than the controls (1.8 vs 1.1 and 4.5 vs 2.8 g, respectively; P < 0.01 in both) and showed a linear trend with the incidence of AVN (chi2 test for trend, P < 0.01 in both). Lupus anticoagulant was associated with AVN (P = 0.02, odds ratio 2.88 [1.14- 7.28]). Logistic regression analysis revealed that the highest cumulative prednisolone dose administered in 4 months, the maximum and mean daily prednisolone dosage, and the lupus anticoagulant were independent risk factors for AVN. CONCLUSIONS: Corticosteroid remains the major predisposing factor for AVN in SLE. Patients who require an initial high-dose steroid for disease control are at risk of AVN, especially if they are positive for the lupus anticoagulant or develop Cushingoid habitus after steroid treatment. High-risk patients should be closely monitored so that early AVN can be diagnosed by sensitive techniques such as magnetic resonance imaging and radioisotope bone scanning.      

Frontal and temporal contributions to understanding the iconic co‐speech gestures that accompany speech

In everyday conversation, listeners often rely on a speaker's gestures to clarify any ambiguities in the verbal message. Using fMRI during naturalistic story comprehension, we examined which brain regions in the listener are sensitive to speakers' iconic gestures. We focused on iconic gestures that contribute information not found in the speaker's talk, compared with those that convey information redundant with the speaker's talk. We found that three regions—left inferior frontal gyrus triangular (IFGTr) and opercular (IFGOp) portions, and left posterior middle temporal gyrus (MTGp)—responded more strongly when gestures added information to nonspecific language, compared with when they conveyed the same information in more specific language; in other words, when gesture disambiguated speech as opposed to reinforced it. An increased BOLD response was not found in these regions when the nonspecific language was produced without gesture, suggesting that IFGTr, IFGOp, and MTGp are involved in integrating semantic information across gesture and speech. In addition, we found that activity in the posterior superior temporal sulcus (STSp), previously thought to be involved in gesture‐speech integration, was not sensitive to the gesture‐speech relation. Together, these findings clarify the neurobiology of gesture‐speech integration and contribute to an emerging picture of how listeners glean meaning from gestures that accompany speech. Hum Brain Mapp 35:900–917, 2014. © 2012 Wiley Periodicals, Inc.     

Primary alveolar soft part sarcoma arising from the cerebellopontine angle

Introduction

Alveolar soft part sarcoma (ASPS), a rare soft tissue malignant neoplasm, frequently metastasizes to the brain. However, primary intracranial ASPS is extremely rare. We present a case of primary intracranial ASPS arising from the cerebellopontine angle (CPA) without demonstrable systemic lesions.

Case report

An 11-year-old girl presented with a recurrent tumor in the right CPA after a partial resection and radiation therapy (RT). Near-total resection with a minimal tumor left in the jugular foramen was performed. The pathological diagnosis was ASPS. There was no evidence of primary extracranial tumors. She underwent adjuvant chemotherapy and gamma knife surgery. At 29 months after the second surgery, magnetic resonance imaging revealed multifocal enhancing lesions at the prepontine cistern, right CPA and medulla oblongata, despite intensive treatment. However, extracranial metastasis was not noted. This case suggested a poor outcome of primary intracranial ASPS, similar to extracranial ASPS.