The association between paramedic service system hospital offload time and response time

OBJECTIVE

To address an important care issue in Canada, we tested the association between paramedic system hospital offload and response time, while considering the impact of other system-level factors.

METHODS

Data from Calgary, Alberta (2014-2017), included median offload (exposure) and response (outcome) time aggregated by hour, with covariates paramedic system episodes of care-dispatch and arrival of a response unit-and hospital transport arrivals (collectively called volume), time of day, and season. Analyses used linear regression and modified Poisson models.

RESULTS

301,105 EMS episodes of care over 26,193 1-h periods were included. For any given 1-h period, the median (IQR) across all episodes of care for offload time, response time, episodes of care, and hospital transport arrivals were 55.3 (45.7, 66.3) min, 8.6 (7.6, 9.8) min, 12 (8, 16) episodes, and 8 (5, 10) hospital arrivals, respectively. Multivariable modelling revealed a complex association differing over levels of exposure and covariates, requiring description using "light stress" and "heavy stress" system scenarios. The light scenario was defined as median offload of 30 min and volume < 10th percentile (six episodes and four hospital arrivals), in the summer, and the heavy scenario as median offload of 90 min and volume > 90th percentile (17 episodes and 13 hospital arrivals), in the winter. An increase is reported in minutes:seconds for median hourly response time between scenarios by time of day: 1:04-4:16 (0000-0559 h.), 0:42-2:05 (0600-1159 h.), 0:57-3:01 (1200-1759 h.), and 0:18-2:21 (1800-2359 h.).

CONCLUSIONS

Increasing offload is associated with increased response time; however the relationship is complex, with a greater impact on response time noted in select situations such as high volume in the winter. These observations illustrate the interdependence of paramedic, ED, and inpatient systems and provide high-yield targets for polices to mitigate the risk to community availability of paramedic resources at times of high offload delay/system stress.

In situ synthesis of high-quantum-efficiency and stable bromide-based blue-emitting perovskite nanoplatelets

We present a facile synthetic approach for the growth of two-dimensional CsPbBr₃ nanoplatelets (NPLs) in the temperature range of 50-80 °C via the vacuum-assisted low-temperature (VALT) method. In this method, we utilized the solubility of the PbBr₂ precursor at temperatures high than the reaction temperature, thus making Br available during the reaction to form NPLs with fewer defects. The high chemical availability of Br during the reaction changes the growth dynamics and formation of highly crystalline nanoplatelets. Using this method, we have synthesized NPLs with an emission wavelength range of 450 to 485 nm that have high photoluminescence quantum yields (PLQY) from 80 to 100%. The synthesized NPLs retain their initial PLQY of about 80% after one month at ambient conditions. The formation of NPLs with fewer defects and enhanced radiative recombination was further confirmed by X-ray diffraction (XRD), reduced Urbach energy, time-resolved photocurrent measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared (FTIR) spectroscopy. Additionally, we utilized the synthesized NPLs for the fabrication of down-conversion light emitting diodes (LEDs), and the electroluminescence peak was barely shifted compared to the photoluminescence peak.

Modification of Cellulose Nanocrystals With 2-Carboxyethyl Acrylate in the Presence of Epoxy Resin for Enhancing its Adhesive Properties

Cellulose nanocrystals (CNCs) have unparalleled advantages in the preparation of nanocomposites for various applications. However, a major challenge associated with CNCs in nanocomposite preparation is the lack of compatibility with hydrophobic polymers. The hydrophobic modification of CNCs has attracted increasing interest in the modern era standing with long challenges and being environmentally friendly. Here, we synthesized CNCs by using cotton as raw material and then modified them with 2-carboxyethyl acrylate to improve their corresponding mechanical, adhesive, contact angle, and thermal properties. Different concentrations (1–5 wt%) of CNCs were used as modifiers to improve the interfacial adhesion between the reinforced CNCs and E-51 (Bisphenol A diglycidyl ether) epoxy resin system. CNCs offered a better modulus of elasticity, a lower coefficient of energy, and thermal expansion. Compared with the standard sample, the modified CNCs (MCNCs) showed high shear stress, high toughness, efficient degradation, thermal stability, and recycling due to the combined effect of the hyperbranched topological structure of epoxy with good compatibility. The native CNCs lost their hydrophilicity after modification with epoxy, and MCNCs showed good hydrophobic behavior (CA = 105 ± 2°). The findings of this study indicate that modification of CNCs with 2-carboxyethyl acrylate in the presence of epoxy resin and the enhancement of the features would further expand their applications to different sectors.

Linkage of Emergency Medical Services and Hospital Data: A Necessary Precursor to Improve Understanding of Outcomes of Prehospital Care

Objective: Linking emergency medical services (EMS) data to hospital outcomes is important for quality assurance and research initiatives. However, non-linkage due to missing or incomplete patient information may increase the risk of bias and distort findings. The purpose of this study was to explore if an optimization strategy, in addition to an existing linkage process, improved the linkage rate and reduced selection and information bias.Methods: 4,150 transported patients in a metropolitan EMS system in Alberta, Canada from 2016/17 were linked to two Emergency Department (ED) databases by a standard strategy using a unique health care number, date/time of ED arrival, and hospital name. An optimized strategy added additional linkage steps incorporating last name, year of birth, and a manual search. The strategies were compared to assess the rate of linkage, and to describe event and patient-level characteristics of unlinked records.Results: The standard strategy resulted in 3,650 out of 4,150 (88.0%) linked records (95% CI 86.9%-88.9%). Of the 500 non-linked records, an additional 381 were linked by the optimized strategy (n = 4,031/4,150 [97.1%; 95% CI: 96.6%-97.6%]). There were no false positive linkages. The highest linkage failure was in 25 to 34 year-old patients (n = 93/478, 19.5%), males (n = 236/1975, 12.0%), Echo level events (n = 15/77, 19.5%), and emergency transport (45/231, 19.5%). The optimized strategy improved linkage in these groups by 68.8% (64/93), 79.2% (187/236), 40.0% (6/15), and 51.1% (23/45) respectively. For dispatch card, the highest linkage failure occurred in Card 24-Pregnancy/Childbirth/Miscarriage (n = 30/44, 68.2%), Card 27-Stab/Gunshot/Penetrating Trauma (n = 6/17, 35.3%), and Card 9-Cardiac/Respiratory Arrest/Death (n = 12/46, 26.1%). The optimized strategy improved linkage by 10.0% (3/30), 83.3% (5/6), and 41.7% (5/12) respectively. For the 119 unlinked records, 71 (59.7%) had sufficient information for linkage, but no appropriately matching records could be found.Conclusion: An optimized sequential deterministic strategy linking EMS data to ED outcomes improved the linkage rate without increasing the number of false positive links, and reduced the potential for bias. Even with adequate information, some records were not linked to their ED visit. This study underscores the importance of understanding how data are linked to hospital outcomes in EMS research and the potential for bias.

A p-n Heterojunction Based Pd/PdO@ZnO Organic Frameworks for High-Sensitivity Room-Temperature Formaldehyde Gas Sensor

As formaldehyde is an extremely toxic volatile organic pollutant, a highly sensitive and selective gas sensor for low-concentration formaldehyde monitoring is of great importance. Herein, metal-organic framework (MOF) derived Pd/PdO@ZnO porous nanostructures were synthesized through hydrothermal method followed by calcination processes. Specifically, porous Pd/PdO@ZnO nanomaterials with large surfaces were synthesized using MOFs as sacrificial templates. During the calcination procedure, an optimized temperature of 500°C was used to form a stable structure. More importantly, intensive PdO@ZnO inside the material and composite interface provides lots of p-n heterojunction to efficiently manipulate room temperature sensing performance. As the height of the energy barrier at the junction of PdO@ZnO exponentially influences the sensor resistance, the Pd/PdO@ZnO nanomaterials exhibit high sensitivity (38.57% for 100 ppm) at room temperature for 1-ppm formaldehyde with satisfactory selectivity towards (ammonia, acetone, methanol, and IPA). Besides, due to the catalytic effect of Pd and PdO, the adsorption and desorption of the gas molecules are accelerated, and the response and recovery time is as small as 256 and 264 s, respectively. Therefore, this MOF-driven strategy can prepare metal oxide composites with high surface area, well-defined morphology, and satisfactory room-temperature formaldehyde gas sensing performance for indoor air quality control.

Biodegradation of total petroleum hydrocarbons (TPH) in highly contaminated soils by natural attenuation and bioaugmentation

Bioremediation is an emerging and sustainable technique that can either occur naturally or be enhanced by introducing nutrients or bacteria able to degrade specific contaminants. In this study, the efficiencies of natural attenuation with nutrients, and bioaugmentation with nutrients and a consortium of five exogenous bacteria, were evaluated for total petroleum hydrocarbon (TPH) degradation in five highly contaminated soils from China, and Kuwait. The bioaugmentation treatment exhibited better efficiencies than the natural attenuation, and reached 48.10% of TPH degradation with a half-life of 41.76 d. The addition of exogenous bacteria also increased the removal of TPH in the highest contaminated soil sample. The concentration of TPH in that soil was reduced from 236, 500 mg kg^-1 of dry soil to 176, 566 mg kg^-1 of dry soil in 40 d, which was equivalent to 25.4% degradation of TPH. The degradation rate (1501.8 mg kg^-1d^-1 of TPH) was higher than those reported in previous studies with a lower concentration of TPH. The bioaugmented strains could withstand high concentrations of TPH and thrive in five different types of soils. Consequently, these strains can be used to remediate soils that are heavily contaminated with petroleum hydrocarbons.

Design, Development and Optimization of S (-) Atenolol Floating Sustained Release Matrix Tablets Using Surface Response Methodology

The objective of this present investigation was to develop and formulate floating sustained release matrix tablets of s (-) atenolol, by using different polymer combinations and filler, to optimize by using surface response methodology for different drug release variables and to evaluate the drug release pattern of the optimized product. Floating sustained release matrix tablets of various combinations were prepared with cellulose-based polymers: Hydroxypropyl methylcellulose, sodium bicarbonate as a gas generating agent, polyvinyl pyrrolidone as a binder and lactose monohydrate as filler. The 3² full factorial design was employed to investigate the effect of formulation variables on different properties of tablets applicable to floating lag time, buoyancy time, % drug release in 1 and 6 h (D_{1 h,}D_{6 h}) and time required to 90% drug release (t_90%). Significance of result was analyzed using analysis of non variance and P < 0.05 was considered statistically significant. S (-) atenolol floating sustained release matrix tablets followed the Higuchi drug release kinetics that indicates the release of drug follows anomalous (non-Fickian) diffusion mechanism. The developed floating sustained release matrix tablet of improved efficacy can perform therapeutically better than a conventional tablet.

Systemic cytomegalovirus infection complicating ulcerative colitis: a case report and review of the literature

Cytomegalovirus is a common infection worldwide and in the immunocompromised individual it can be a major cause of morbidity and mortality. In patients with inflammatory bowel disease cytomegalovirus infection has been described in both immunocompetent and immunocompromised individuals. A 34 year old man with an exacerbation of his colitis was diagnosed as having both cytomegalovirus colitis and hepatitis. The diagnosis was made on the classical appearance of "owl's eye" inclusion bodies on colonic and hepatic biopsies and, in addition, viral serology and polymerase chain reaction (PCR) analysis of the cytomegalovirus DNA copy number. Fourteen days of treatment with ganciclovir led to a prompt improvement in the symptoms of colitis, resolution of the pyrexia, normalisation of the liver function tests, and clearance of the virus, as measured by a negative cytomegalovirus DNA PCR. Cytomegalovirus infection is a potentially fatal complication of treatment induced immunosuppression in patients with inflammatory bowel disease. As in this case, infection may be systemic and not confined to the intestine. Prompt diagnosis using histology, serology, and PCR analysis allows prompt introduction of therapy and an improved prognosis.

A prospective multicenter study of cervical spine injury in children

OBJECTIVE

Pediatric victims of blunt trauma have developmental and anatomic characteristics that can make it difficult to assess their risk of cervical spine injury (CSI). Previous reports, all retrospective in nature, have not identified any cases of CSI in either children or adults in the absence of neck pain, neurologic symptoms, distracting injury, or altered mental status. The objective of this study was to examine the incidence and spectrum of spine injury in patients who are younger than 18 years and to evaluate the efficacy of the National Emergency X-Radiography Utilization Study (NEXUS) decision instrument for obtaining cervical spine radiography in pediatric trauma victims.

METHODS

We performed a prospective, multicenter study to evaluate pediatric blunt trauma victims. All patients who presented to participating emergency departments underwent clinical evaluation before radiographic imaging. The presence or absence of the following criteria was noted: midline cervical tenderness, altered level of alertness, evidence of intoxication, neurologic abnormality, and presence of painful distracting injury. Presence or absence of each individual criterion was documented for each patient before radiographic imaging, unless the patient was judged to be too unstable to complete the clinical evaluation before radiographs. The decision to radiograph a patient was entirely at the physician's discretion and not driven by the NEXUS questionnaire. The presence or absence of CSI was based on the final interpretation of all radiographic studies. Data on all patients who were younger than 18 years were sequestered from the main database for separate analysis.

RESULTS

There were 3065 patients (9.0% of all NEXUS patients) who were younger than 18 years in this cohort, 30 of whom (0.98%) sustained a CSI. Included in the study were 88 children who were younger than 2, 817 who were between 2 and 8, and 2160 who were 8 to 17. Fractures of the lower cervical vertebrae (C5-C7) accounted for 45.9% of pediatric CSIs. No case of spinal cord injury without radiographic abnormality was reported in any child in this study, although 22 cases were reported in adults. Only 4 of the 30 injured children were younger than 9 years, and none was younger than 2 years. Tenderness and distracting injury were the 2 most common abnormalities noted in patients with and without CSI. The decision rule correctly identified all pediatric CSI victims (sensitivity: 100.0%; 95% confidence interval: 87.8%-100.0%) and correctly designated 603 patients as low risk for CSI (negative predictive value: 100.0%; 95% confidence interval: 99.4%-100.0%).

CONCLUSIONS

The lower cervical spine is the most common site of CSI in children, and fractures are the most common type of injury. CSI is rare among patients aged 8 years or younger. The NEXUS decision instrument performed well in children, and its use could reduce pediatric cervical spine imaging by nearly 20%. However, the small number of infants and toddlers in the study suggests caution in applying the NEXUS criteria to this particular age group.

Emergency department utilization by noninstitutionalized elders

OBJECTIVES

To the best of the authors' knowledge, no nationally representative, population-based study has characterized the proportion of elders using the emergency department (ED) and factors associated with ED use by elders. This article describes the proportion of elder Medicare beneficiaries using the ED and identifies attributes associated with elder ED users as compared with nonusers.

METHODS

The 1993 Medicare Current Beneficiary Survey was used, a national, population-based, cross-sectional survey of Medicare beneficiaries linked with Medicare claims data. The study population was limited to 9,784 noninstitutionalized individuals aged 66 years or older. The Andersen model of health service utilization was used, which explains variation in ED use through a combination of predisposing (demographic and social), enabling (access to care), and need (comorbidity and health status) characteristics.

RESULTS

Eighteen percent of the sample used the ED at least once during 1993. Univariate analysis showed ED users were older; were less educated and lived alone; had lower income and higher Charlson Comorbidity Index scores; and were less satisfied with their ability to access care than nonusers (p < 0.01, chi-square). Logistic regression identified older age, less education, living alone, higher comorbidity scores, worse reported health, and increased difficulties with activities of daily living as factors associated with ED use (p < 0.05). Need characteristics predicted ED use with the greatest accuracy.

CONCLUSIONS

The proportion of elder ED users is slightly higher than previously reported among Medicare beneficiaries. Need (comorbidity and health status) characteristics predict ED utilization with the greatest accuracy.

Does fluorescent urine indicate antifreeze ingestion by children?

OBJECTIVE

Fluorescent urine has been reported to indicate antifreeze ingestion. Recently, we evaluated a child who was suspected of ethylene glycol ingestion. Although she had fluorescent urine, subsequent studies showed that she had not ingested antifreeze. We tested whether fluorescent urine indicates antifreeze ingestion by children.

METHODS

A convenience sample of urine specimens from 30 hospitalized children was obtained. All of the patients had been hospitalized for reasons unrelated to poisoning. The specimens were viewed with a Wood's lamp, and the samples were identified as fluorescent or not fluorescent. A second convenience sample of urine specimens from a group of 16 healthy children was obtained, and these specimens were identified as fluorescent or not fluorescent in a similar manner.

RESULTS

The majority of urine specimens obtained from children are fluorescent. There is variation in the interpretation of urine fluorescence among observers. The type of container used may influence the finding of fluorescence.

CONCLUSIONS

Fluorescent urine is not an indicator of ethylene glycol antifreeze ingestion by children.

Diffuse lamellar keratitis associated with epithelial defects after laser in situ keratomileusis

PURPOSE

To describe the association between the presence of epithelial defects and the development of diffuse lamellar keratitis (DLK), "Sands of the Sahara" syndrome, following laser in situ keratomileusis (LASIK).

SETTING

Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA.

METHODS

In this retrospective study, the postoperative clinical course and surgical outcomes in 735 eyes of 358 consecutive patients who had myopic LASIK between December 1998 and August 1999 were reviewed. Of the 735 procedures, 680 were primary LASIK procedures and 55 were retreatments performed by lifting the existing flaps. The incidence and severity of DLK and the relationship of DLK to epithelial defects were tabulated.

RESULTS

Diffuse lamellar keratitis developed in 9 of the 16 eyes that had postoperative epithelial defects. Seventeen eyes without epithelial defects also developed DLK. The presence of an epithelial defect increased an individual's risk of developing DLK 24 times (95% confidence interval, 13 to 45). In 8 eyes, the inflammation resolved following treatment with intense topical corticosteroids. One eye had irrigation under the flap because of dense central inflammation; the final outcome was mild inferior corneal steepening. All eyes recovered preoperative best spectacle-corrected visual acuities.

CONCLUSION

Patients who have epithelial defects of any size following LASIK are at significantly increased risk of developing DLK.

A comparative, qualitative and quantitative antimicrobial efficacies of mouthrinses containing chlorhexidine gluconate and essential oils

A project was launched to evaluate and compare antimicrobial efficacy of Hexidine and Listerine over placebo in 10 day human experimental gingivitis study. A rigid study schedule for subject compliance spanning well over 3 months was sorted out and volunteers recruited for study rinsed all the 3 assigned mouthrinses containing (a) chlorhexidine gluconate, (b) "essential oils" and (c) flavoured distilled water one after the other at certain prefixed intervals. After 10 days of assigned mouthrinse regimen, where the assigned mouthrinse was the only method practiced by the volunteers for oral hygiene, Supragingival Plaque was quantitatively and qualitatively assayed. Qualitatively supragingival plaque was assayed by Gram staining (Direct smear and Thioglycollate Broth) and growth characteristics i.e; Aerobic, Microaerophilic and Anaerobic growth was noted. Quantitatively plaque was assayed by calculating total microbial load per tooth by preparing Mafarland Nephelometer standard and Spectrophotometric analysis. It is concluded that Hexidine and Listerine exert similar antimicrobial efficacy in 10 days experimental gingivitis study. Hexidine and Listerine exert their antimicrobial influence through reduction of total Aerobes and Anaerobes reducing total microbial load per tooth by 58% and 53% respectively as compared to placebo.

A comparison of methods for the detection of myocardial ischemia during noncardiac surgery: automated ST-segment analysis systems, electrocardiography, and transesophageal echocardiography

Clinicians often fail to detect intraoperative ischemic electrocardiographic (ECG) changes when viewing oscilloscopes. Automated ST-segment monitors promise to increase the detection of such ECG changes. We investigated the capacity of two commercially available ST-segment monitors to detect intraoperative myocardial ischemia in patients at high risk for developing intraoperative myocardial ischemia during vascular and other noncardiac procedures. The ST-segment monitors were compared with two reference monitors: (a) printed eight-lead ECGs, as interpreted by a cardiologist, and (b) the presence of segmental wall motion abnormalities and thickening abnormalities detected by transesophageal echocardiography (TEE). We also examined the capacity of the printed ECG to diagnose myocardial ischemia when compared with TEE. We studied 44 patients who underwent TEE, printed multilead ECG, oscilloscope monitoring of leads V5 and II, and measurement of ST-segment deviation from the baseline using an automated Hewlett Packard ST-segment device. The sensitivities for the Hewlett Packard system were 40% for TEE-diagnosed myocardial ischemia and 75% for ECG-diagnosed ischemia. Comparison of the printed ECG with TEE revealed that ST-segment changes in the printed ECG, as analyzed by a cardiologist, were 25% sensitive and 62% specific for the detection of TEE-diagnosed myocardial ischemia. When T-wave inversions were added to ST-segment depression as a criterion for the diagnosis of myocardial ischemia by the printed ECG, the sensitivity of ECG for the detection of intraoperative myocardial ischemia, as determined by TEE, was 40% and specificity was 58%. Twenty-three of the 44 patients were simultaneously monitored in leads I, II, and V5 with an automated Marquette ST-segment monitor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult foregut duplication

We report a gastric duplication in a 23-year-old man. The case is unique because the stomach is the rarest location for enteric duplication, the duplication almost never occurs in adults, and the duplication consisted exclusively of pancreatic tissue. This extreme example illustrates the close embryologic and anatomic association between stomach and pancreas. A case is made for the use of the general term of foregut duplication to avoid confusing nomenclature.