A Retrospective Review of Hospitalized Patients Receiving a Higher than Maximum Dose of Acetaminophen.

BACKGROUND: Although the 3 to 4 gram per 24 hours dose recommended for daily use are generally safe, case reports and some series raise concerns about nonacute excessive doses in some individuals. OBJECTIVE: To assess the safety of dosing more than 4 grams of acetaminophen in a 24-hour period in hospitalized patients and develop a method to evaluate the ongoing practice of acetaminophen dosing. Methods: We performed a retrospective chart review of supratherapeutic doses of acetaminophen over a 2-year period. Outcomes included death and the need for liver transplant. A "best practices alert" (BPA) was then developed in our EMR when more than 4 grams of acetaminophen was either prescribed or administered in a 24- hour period. Twelve months of alerts were then retrospectively reviewed and evaluated. RESULTS: 152 cases of dosing more than 4 grams were initially identified. No cases of death related to liver failure or liver transplant were found in any of these patients. 482 cases were identified after a BPA was put in place where the alert was overridden. There were no deaths and no cases that required liver transplantation due to liver failure. The majority of overrides were due to the allowed window of timing for nursing administration of acetaminophen for scheduled doses and overlap with as needed dosing. CONCLUSION: Supratherapeutic dosing of acetaminophen in our patients did not lead to death or liver transplant. A BPA in our EMR has allowed better evaluation of patterns of acetaminophen use at our university health system.

Evaluation of Fossil Amber Birefringence and Inclusions Using Terahertz Time-Domain Spectroscopy.

Using a cross-polarization transmission geometry, stress maps for the normalized birefringence and intrinsic stress direction of polymeric materials may be obtained using terahertz nondestructive evaluation. The analysis method utilizes a deconvolution method to determine the arrival times and amplitude of the cross-polarized terahertz pulses through a birefringent material. Using amber (a naturally occurring polymer) as a material of interest, stress maps show that inclusion-free Lebanese amber samples behave as classic uniaxial birefringent (photoelastic) materials whose principal stress directions, as inferred in the terahertz spectral range, agree well with visible photoelasticity measurements. Since amber samples, depending upon their source, may be either transparent or opaque to visible light, comparing birefringence measurements in the visible and terahertz spectral ranges cross-validates the stress measurements, thereby establishing a strong and unique stress analysis methodology for visibly opaque samples. While the material of interest for this paper is amber, the method is generally applicable for any terahertz-transparent polymer. The cross-polarization experimental configuration enables stress levels within the amber matrix to be visualized while also outlining highly localized regions of stress surrounding inclusions. Birefringence stress maps clearly show localized increases in stress magnitude and directional changes surrounding inclusions.

Chronic effects of blast injury on the microvasculature in a transgenic mouse model of Alzheimer's disease related Aß amyloidosis.

BACKGROUND: Altered cerebrovascular function and accumulation of amyloid-ß (Aß) after traumatic brain injury (TBI) can contribute to chronic neuropathology and increase the risk for Alzheimer's disease (AD). TBI due to a blast-induced shock wave (bTBI) adversely affects the neurovascular unit (NVU) during the acute period after injury. However, the chronic effects of bTBI and Aß on cellular components of the NVU and capillary network are not well understood. METHODS: We exposed young adult (age range: 76-106 days) female transgenic (Tg) APP/PS1 mice, a model of AD-like Aß amyloidosis, and wild type (Wt) mice to a single bTBI (~ 138 kPa or ~ 20 psi) or to a Sham procedure. At 3-months or 12-months survival after exposure, we quantified neocortical Aß load in Tg mice, and percent contact area between aquaporin-4 (AQP4)-immunoreactive astrocytic end-feet and brain capillaries, numbers of PDGFRß-immunoreactive pericytes, and capillary densities in both genotypes. RESULTS: The astroglia AQP4-capillary contact area in the Tg-bTBI group was significantly lower than in the Tg-Sham group at 3-months survival. No significant changes in the AQP4-capillary contact area were observed in the Tg-bTBI group at 12-months survival or in the Wt groups. Capillary density in the Tg-bTBI group at 12-months survival was significantly higher compared to the Tg-Sham control and to the Tg-bTBI 3-months survival group. The Wt-bTBI group had significantly lower capillary density and pericyte numbers at 12-months survival compared to 3-months survival. When pericytes were quantified relative to capillary density, no significant differences were detected among the experimental groups, for both genotypes. CONCLUSION: In conditions of high brain concentrations of human Aß, bTBI exposure results in reduced AQP4 expression at the astroglia-microvascular interface, and in chronic capillary proliferation like what has been reported in AD. Long term microvascular changes after bTBI may contribute to the risk for developing chronic neurodegenerative disease later in life.

A Retrospective Review of the Presentation and Treatment of Stingray Stings Reported to a Poison Control System.

We studied stingray stings reported to our poison system to identify associated complications and treatments. We undertook a 14-year retrospective observational analysis of stingray stings reported to our poison system. Extracted data included caller age and gender, outcome, management site, symptoms, treatments, and geographical location of the sting. We examined suspected infection rate, hot water treatment efficacy, and possible presence of foreign bodies in the wound. Suspected infection rate was defined as "possible infection" or "likely infection." Hot water treatment efficacy was defined as cases that encoded hot water as a treatment and noted pain relief within 1 hour of treatment in the free-text record, before documentation of other analgesic administration. A total of 576 envenomations were reported. The majority were men (76%), with an average age of 24 years (range, 6-78 years). Symptoms were reported in 485 cases. A total of 9% recorded a foreign body or debris at the wound site. Symptoms included pain (79%), puncture wound (65%), and edema (25%). Infections were reported in 9% of cases. Hot/warm water immersion appeared effective for pain relief in 69% of cases where outcome was documented. The most common geographical location of stingray envenomations was Southern California. Stingray stings are common in California. Hot/warm water seemed to be effective in pain management in our series, whereas foreign bodies or retained spines and infections were other identified complications.