Effectiveness of glucagon in relieving esophageal foreign body impaction: a multicenter study.

PURPOSE: Glucagon is thought to decrease lower esophageal sphincter tone and is used as an alternative to invasive endoscopy for esophageal foreign body impaction (EFBI). The purpose of this study was to evaluate efficacy and safety of glucagon and identify characteristics associated with success. METHODS: A multicenter, retrospective study of patients receiving glucagon for EFBI at 2 academic emergency departments was conducted between 2006 and 2010. A control group of patients that did not receive glucagon was evaluated. Data collection included demographics, type of foreign body, glucagon dose, resolution of impaction, incidence of vomiting, additional medication, and endoscopy required. Descriptive and univariate analysis was performed as appropriate. RESULTS: A total of 133 doses of glucagon were administered in 127 patients. Glucagon-related resolution of EFBI occurred in 18 patients (14.2%) and vomiting in 16 patients (12.6%). No statistical differences between successful and unsuccessful groups were seen with the exception of concomitant medication administration (benzodiazepine or nitroglycerin) being associated with less glucagon success, 33.3% vs 59.6%, respectively (P = .04). Eighty-four percent of patients in the unsuccessful group underwent endoscopy. Comparing those that received glucagon (n = 127) and the control group (n = 29), there was no significant difference in resolution of EFBI, 14.2% vs 10.3%, respectively (P = .586). CONCLUSIONS: Glucagon-related resolution occurred in 14.2% of patients and was not significantly different compared with those that did not receive glucagon (10.3%). Concomitant medication administration was associated with lower success. Overall, glucagon had a low success rate, was related to adverse effects, and does not offer advantages for treatment.

Nanoparticle characteristics affecting environmental fate and transport through soil.

Nanoparticles are being used in broad range of applications; therefore, these materials probably will enter the environment during their life cycle. The objective of the present study is to identify changes in properties of nanoparticles released into the environment with a case study on aluminum nanoparticles. Aluminum nanoparticles commonly are used in energetic formulations and may be released into the environment during their handling and use. To evaluate the transport of aluminum nanoparticles, it is necessary not only to understand the properties of the aluminum in its initial state but also to determine how the nanoparticle properties will change when exposed to relevant environmental conditions. Transport measurements were conducted with a soil-column system that delivers a constant upflow of a suspension of nanoparticles to a soil column and monitors the concentration, size, agglomeration state, and charge of the particles in the eluent. The type of solution and surface functionalization had a marked effect on the charge, stability, and agglomeration state of the nanoparticles, which in turn impacted transport through the receiving matrix. Transport also is dependent on the size of the nanoparticles, although it is the agglomerate size, not the primary size, that is correlated with transportability. Electrostatically induced binding events of positively charged aluminum nanoparticles to the soil matrix were greater than those for negatively charged aluminum nanoparticles. Many factors influence the transport of nanoparticles in the environment, but size, charge, and agglomeration rate of nanoparticles in the transport medium are predictive of nanoparticle mobility in soil.

Simultaneous measurement of the effective density and chemical composition of ambient aerosol particles.

Simultaneous measurements of the effective density and chemical composition of individual ambient particles were made in Riverside, California by coupling a differential mobility analyzer (DMA) with an ultrafine aerosol time-of-flight mass spectrometer (UF-ATOFMS). In the summer, chemically diverse particle types (i.e., aged-OC, vanadium-OC-sulfate-nitrate, biomass) all had similar effective densities when measured during the same time period. This result suggests that during the summer study the majority of particle mass for the different particle types was dominated by secondary species (OC, sulfates, nitrates) of the same density, while only a small fraction of the total particle mass is accounted for by the primary particle cores. Also shown herein, the effective density is a dynamic characteristic of the Riverside, CA ambient aerosol, changing by as much as 40% within 16 h. During the summer measurement period, changes in the ambient atmospheric water content correlated with changes in the measured effective densities which ranged from approximately 1.0 to 1.5 g x cm(-3). This correlation is potentially due to evaporation of water from particles in the aerodynamic lens. In contrast, in the fall during a Santa Ana meteorological event, ambient particles with a mobility diameter of 450 nm showed three distinct effective densities, each related to a chemically unique particle class. Particles with effective densities of approximately 0.27 g x cm(-3), 0.87 g x cm(-3), and 0.93 g x cm(-3) were composed mostly of elemental carbon, lubricating oil, and aged organic carbon, respectively. It is interesting to contrast the seasonal differences where in the summer, particle density and mass were determined by high amounts of secondary species, whereas in the fall, relatively clean and dry Santa Ana conditions resulted in freshly emitted particles which retained their distinct source chemistries and densities.

Etomidate and midazolam for procedural sedation: prospective, randomized trial.

OBJECTIVE: To evaluate whether there is a difference in the time of sedation and time to patient disposition in patients undergoing procedural sedation with etomidate and midazolam. METHODS: Prospective, randomized, double-blind trial comparing etomidate (0.10 mg/kg) and midazolam (0.035 mg/kg) for patients requiring procedural sedation for reduction of joint dislocations or long bone fractures. RESULTS: Forty-five patients were enrolled (24 randomized to etomidate, 21 to midazolam). Groups were similar in demographics and analgesic dosing. Mean time of sedation for etomidate was 15 minutes (SD, 10.97) and for midazolam was 32 minutes (SD, 16.13) (P<.001). Mean time to disposition for etomidate was 121 minutes (SD, 73.28) and for midazolam was 111 minutes (SD, 96.36) (P=.700). The mean quality of sedation for etomidate was 7.91 (SD, 1.53) and for midazolam was 7.48 (SD, 2.89) (P=.570). CONCLUSIONS: The use of etomidate compared with midazolam for procedural sedation provides a significant reduction in recovery time, without a reduction in time to patient disposition, while providing equal sedation quality.

Necessity of hospital admission for pediatric minor head injury.

The objective of this study was to evaluate the need for mandatory hospital admission of all pediatric patients with minor head injury (MHI) and negative computed tomographic (CT) scans for head injury. The study was a retrospective chart review of all patients admitted to a pediatric trauma service over a period of 4 years. MHI was defined as blunt head trauma with a Glasgow Coma Scale (GCS) score of 15 and a nonfocal neurological examination. Only patients < or = 13 years of age and with a negative head CT scan were included, and during hospitalization all patients were observed for delayed complications. A total of 197 patients met the inclusion criteria. The patients' mean age was 7.1 years, with a range of 2 months to 13 years. The most common mechanisms of injury were being struck by a motor vehicle while walking (82 patients), and falling (75 patients). No complications were observed, and although persistent symptoms occurred in 5 patients, they did not delay discharge. We conclude that pediatric patients with MHI and negative CT scans of the head do not require routine admission for observation for delayed complications.

The effect of hypertension on uncontrolled hemorrhage in a rodent model.

UNLABELLED: Patients with essential hypertension (EH) have higher mortality rates from hemorrhage. How the complex physiologic changes seen in EH affect the response to uncontrolled hemorrhage has yet to be adequately described. OBJECTIVE: To test the null hypothesis that there would be no difference in the hemorrhage volumes and hemodynamic responses to uncontrolled hemorrhage between hypertensive rats (SHRs) and normotensive rats (WKYs). METHODS: Twenty-four adult rats (12 WKYs and 12 SHRs) were anesthetized with althesin via the intra-peritoneal route. The femoral artery was cannulated by cutdown for mean arterial pressure (MAP) measurement and blood gas sampling. Twelve rats (6 WKYs and 6 SHRs) underwent uncontrolled hemorrhage by 50% tail amputation. Twelve rats (6 WKYs and 6 SHRs) served as non-hemorrhage controls. The MAP, base excess (BE), and cumulative blood loss were measured pre-hemorrhage and then every 15 minutes post-hemorrhage for 90 minutes. Data were reported as mean +/- standard error of the mean. Comparisons between control and uncontrolled hemorrhage groups were analyzed by analysis of variance (ANOVA) with repeated-measures post-hoc testing by Bonferroni. Statistical significance was defined by an alpha = 0.05. RESULTS: Mortality rates were significantly higher (p < 0.05) for the SHRs (100%) as compared with the WKYs (33%). Changes in time-averaged MAP post-hemorrhage were significantly greater (p < 0.001) in the SHR group (88 +/- 10 mm Hg) as compared with the WKY group (48 +/- 4 mm Hg). Hemorrhage volume was significantly lower (p = 0.02) in the SHR group (3.7 +/- 0.5 mL) as compared with the WKY group (6.1 +/- 0.7 mL). CONCLUSIONS: Hypertensive rats had a higher mortality rate than normotensives from a comparable vascular injury with lower hemorrhage volumes.