Evaluation of Concordance Between Original Death Certifications and an Expert Panel Process in the Determination of Sudden Unexplained Death in Childhood.

Importance: The true incidence of sudden unexplained death in childhood (SUDC), already the fifth leading category of death among toddlers by current US Centers for Disease Control and Prevention estimates, is potentially veiled by the varied certification processes by medicolegal investigative offices across the United States. Objective: To evaluate the frequency of SUDC incidence, understand its epidemiology, and assess the consistency of death certification among medical examiner and coroner offices in the US death investigation system. Design, Setting, and Participants: In this case series, 2 of 13 forensic pathologists (FPs) conducted masked reviews of 100 cases enrolled in the SUDC Registry and Research Collaborative (SUDCRRC). Children who died aged 11 months to 18 years from 36 US states, Canada, and the United Kingdom had been posthumously enrolled in the SUDCRRC by family members from 2014 to 2017. Comprehensive data from medicolegal investigative offices, clinical offices, and family members were reviewed. Data analysis was conducted from December 2014 to June 2020. Main Outcomes and Measures: Certified cause of death (COD) characterized as explained (accidental or natural) or unexplained, as determined by SUDCRRC masked review process. Results: In this study of 100 cases of SUDC (mean [SD] age, 32.1 [31.8] months; 58 [58.0%] boys; 82 [82.0%] White children; 92 [92.0%] from the United States), the original pathologist certified 43 cases (43.0%) as explained COD and 57 (57.0%) as unexplained COD. The SUDCRRC review process led to the following certifications: 16 (16.0%) were explained, 7 (7.0%) were undetermined because of insufficient data, and 77 (77.0%) were unexplained. Experts disagreed with the original COD in 40 cases (40.0%). These data suggest that SUDC incidence is higher than the current Centers for Disease Control and Prevention estimate (ie, 392 deaths in 2018). Conclusions and Relevance: To our knowledge, this is the first comprehensive masked forensic pathology review process of sudden unexpected pediatric deaths, and it suggests that SUDC may often go unrecognized in US death investigations. Some unexpected pediatric deaths may be erroneously attributed to a natural or accidental COD, negatively affecting surveillance, research, public health funding, and medical care of surviving family members. To further address the challenges of accurate and consistent death certification in SUDC, future studies are warranted.

A cellular solid model of the lamina cribrosa: mechanical dependence on morphology.

The biomechanics of the optic nerve head (ONH) may underlie many of the potential mechanisms that initiate the characteristic vision loss associated with primary open angle glaucoma. Therefore, it is important to characterize the physiological levels of stress and strain in the ONH and how they may change in relation to material properties, geometry, and microstructure of the tissue. An idealized, analytical microstructural model of the ONH load bearing tissues was developed based on an octagonal cellular solid that matched the porosity and pore area of morphological data from the lamina cribrosa (LC). A complex variable method for plane stress was applied to relate the geometrically dependent macroscale loads in the sclera to the microstructure of the LC, and the effect of different geometric parameters, including scleral canal eccentricity and laminar and scleral thickness, was examined. The transmission of macroscale load in the LC to the laminar microstructure resulted in stress amplifications between 2.8 and 24.5xIOP. The most important determinants of the LC strain were those properties pertaining to the sclera and included Young's modulus, thickness, and scleral canal eccentricity. Much larger strains were developed perpendicular to the major axis of an elliptical canal than in a circular canal. Average strain levels as high as 5% were obtained for an increase in IOP from 15 to 50 mm Hg.

Extraction and analysis of human nuclear and mitochondrial DNA from electron beam irradiated envelopes.

The United States Postal Service is considering methods such as electron beam irradiation to neutralize biological agents sent through the mail. While this is proven to reduce/eliminate pathogenic organisms, it may also degrade human genomic DNA and therefore hinder the ability to garner forensically informative genetic profiles. To determine the effects of electron beam irradiation on DNA typing, 16 white, standard letter-sized envelopes were licked. Half of the envelopes served as nonirradiated controls while the other half underwent irradiation at dosages sufficient to kill anthrax spores (29.3 and 51.6 kGy). Total cellular DNA was extracted from all envelopes; nuclear short tandem repeat loci, as well as the hypervariable region I from mitochondrial DNA, were amplified by means of the polymerase chain reaction. Short tandem repeat profiles and mitochondrial DNA sequence haplotypes were acquired on an ABI Prism 310 Genetic Analyzer platform. Analysis of data from irradiated samples revealed evidence of DNA degradation; however, the ability to construct full genetic profiles from both nuclear and mitochondrial DNA remained largely unaffected. The use of the polymerase chain reaction, coupled with florescent fragment analysis and mitochondrial DNA sequencing, should be considered to profile biological material from evidence enduring irradiation to inactivate infectious agents.

Anterior scleral canal geometry in pressurised (IOP 10) and non-pressurised (IOP 0) normal monkey eyes.

AIMS: To characterise lamina cribrosa and anterior scleral canal wall architecture in pressurised (IOP 10 mm Hg) and non-pressurised (IOP 0 mm Hg) normal monkey eyes. METHODS: Eight normal eyes from eight monkeys were enucleated before sacrifice and the optic nerve heads (ONH) trephined and immersion fixed in glutaraldehyde (IOP 0). Nine normal eyes from nine monkeys were perfusion fixed in situ with paraformaldehyde at IOP 10 mm Hg (IOP 10), and the ONHs trephined and stored in glutaraldehyde. Each ONH specimen was embedded in glycol methacrylate and cut into vertical or horizontal, 4 micro m thick, serial sections. Within digitised images of every sixth section, anterior laminar position and laminar thickness were measured at nine evenly spaced locations across the scleral canal opening. Additionally, scleral canal diameters at Bruch's membrane (SCD-B) and at the anterior laminar insertion (SCD-ALI) were measured within the 15 middle section images of each vertically sectioned ONH. RESULTS: Anterior laminar position was significantly more anterior (nearer Bruch's membrane) in the IOP 10 eyes, compared with the IOP 0 eyes (116 (+/-95% CI; 2) micro m v 184 (2) micro m, respectively). Also in the IOP 10 eyes, the lamina cribrosa was thinner (195 (2) micro m v 264 (2) micro m) and the scleral canal diameter was larger (SCD-B: 1751 (23) micro m v 1591 (19) micro m; SCD-ALI: 1961 (21) micro m v 1717 (17) micro m), compared with the IOP 0 eyes. CONCLUSION: The anterior scleral canal wall is expanded and the lamina cribrosa is thinned and more tautly stretched within pressurised (perfusion fixed at IOP 10) young monkey eyes, compared with non-pressurised (immersion fixed at IOP 0) young monkey eyes. The constricted scleral canal and the relaxed and thickened lamina in the non-pressurised eyes may represent phenomena that contribute to optic disc swelling in hypotonous eyes.

Posterior scleral thickness in perfusion-fixed normal and early-glaucoma monkey eyes.

PURPOSE: To characterize posterior scleral thickness in the normal monkey eye and to assess the effects of acute (15- to 80-minute) and short-term chronic (3- to 7-week) intraocular pressure (IOP) elevations. METHODS: Both eyes of four normal monkeys (both eyes normal) and four monkeys with early glaucoma (one eye normal and one eye with induced chronic elevation of IOP) were cannulated. In each monkey, IOP was set to 10 mm Hg in the normal eye and 30 or 45 mm Hg in the contralateral eye (normal or early glaucoma) for 15 to 80 minutes. All eight monkeys were perfusion fixed, yielding eight low IOP-normal eyes, four high IOP-normal eyes, and four high IOP-early glaucoma eyes. Posterior scleral thickness was measured histomorphometrically at 15 measurement points within each eye, and the data were grouped by region: foveal, midposterior, posterior-equatorial, and equatorial. RESULTS: Overall, posterior scleral thickness was significantly different in the various regions and among the treatment groups (P < 0.0001). In the low IOP-normal eyes, the posterior sclera was thickest in the foveal region (307 microm) and thinner in the midposterior (199 microm), posterior-equatorial (133 microm), and equatorial (179 microm) regions. In the high IOP-normal and high IOP-early glaucoma eyes, the posterior sclera was thinner both overall and within specific regions, compared with the low IOP-normal eyes. CONCLUSIONS: The posterior sclera in the perfusion-fixed normal monkey eye thins progressively from the fovea to the equator and is thinnest just posterior to the equator. Acute and short-term chronic IOP elevations cause regional thinning within the posterior sclera of some monkey eyes, which significantly increases stresses in the scleral wall.

Suicidal ingestion of barium-sulfide-containing shaving powder.

Physicians, familiar with the common usage of barium medicinally as the contrast agent barium sulfate, may consider it an innocuous or at most a minimally harmful compound. The barium cation is extremely toxic and produces characteristic gastrointestinal symptoms, periorbital and extremity paresthesia, hypertension, and progressive flaccid muscular paralysis. Profound hypokalemia also may be induced. Overdose may be rapidly fatal unless the ingestion is recognized and appropriate treatment is instituted expediently.

Suicide by environmental hypoxia (forced depletion of oxygen).

Suicidal suffocation by forced oxygen depletion (environmental hypoxia) with carbon dioxide (CO2) and with propane is discussed in two cases. No toxicologic proof was available with the former and circumstantial evidence weighed heavily. The latter case demonstrated inhaled propane by an on-scene transthoracic aspirate; all other toxicology specimens, including brain, liver, blood, kidney, fat, and vitreous, did not contain hydrocarbons. This second fatality was complicated by multi-agent overdose, including diphenhydramine, fluoxetine (Prozac), and nordiazepam. The designation of these deaths as due to oxygen depletion involved careful scrutiny of the autopsy, toxicologic, and scene findings. Complete analysis of all factors surrounding these rarely encountered suffocation deaths is stressed.

Handling and interpretation of crossbow injuries.

The longbow and crossbow are infrequently encountered by the forensic pathologist. As these weapons become more popular for sport and hunting, more fatalities may be anticipated. Three crossbow deaths (two homicides and one suicide) are presented. Included is the first report of a multiple shot death. The design and physics of the crossbow are described. The proper preservation of evidence, as well as wound analysis and interpretation, in such deaths are detailed.

Hydrogen peroxide: a source of lethal oxygen embolism. Case report and review of the literature.

Hydrogen peroxide is a readily available clear, odorless liquid that is commonly used as an irrigant for superficial wounds. It is not widely thought of as a poison; however, it may rarely be the cause of accidental death. A case of fatal oxygen embolism in a child after ingestion of hydrogen peroxide is reported. A total of five similar cases have been previously described. Morbidity and mortality have also been reported with the use of hydrogen peroxide in hospitals. Gastric catabolism of hydrogen peroxide produces oxygen and water. When the amount of oxygen evolved exceeds its maximal blood solubility, venous embolization occurs. Hydrogen peroxide should not be considered to be innocuous; it should neither be ingested nor used in situations where the evolved oxygen gas cannot dissipate freely. The ubiquitous nature of household peroxide and its erroneous benign reputation suggest that child-resistant containers are in order. A protocol delineating the medicolegal investigation and postmortem examination of fatalities caused by the ingestion of this substance is offered.

Medical management decisions in nursing home patients. Principles and policy recommendations.

The ethical principles of medical decision making are inherently the same for nursing home residents, who represent an increasingly large segment of the population, as they are for other adult patients. In practice, however, a number of considerations require specialized application of these principles in nursing homes. Notably, a large proportion of nursing home patients are at high risk for morbid and mortal events yet are incapable of expressing medical management preferences due to dementia and confusion. Policies and procedures regarding medical decisions for nursing home patients are needed. We present and discuss a policy for patient care in nursing homes based on recommendations of a national biomedical ethics committee. This policy, which may be adapted for use in specific institutions, explicitly discusses the principles of care and their application in nursing homes. It also encourages prospective decision making and provides advance care directives for patients making and provides advance care directives for patients and their decision-making surrogates to do so.