Forensic Entomology
Bell Suzanne in Forensic Science, 5th Edition, 2019
In the first few hours after death, a forensic pathologist can use the condition of the body (e.g., rigor mortis) to estimate the elapsed time since death. However, about 24–48 hours after death, most of these biological changes are over and are of little value in estimating the postmortem interval (PMI). Certain species of insect depend on carrion or dead animal material to survive. Such insects are therefore very adept at locating a dead animal. Although, for the most part, such carrion insects survive on dead wildlife, humans are also animals, and from an insect’s point of view a dead human is no different from a dead bear or a dead crow. The fly eggs hatch into delicate first-instar or first-stage maggots, which feed on liquid protein. After a brief period, primarily dependent on temperature and species, the first-instar larvae will molt to the second instar, shedding the first-instar larval cuticle and mouthparts.
Known Fingerprints
Hillary Moses Daluz in Fundamentals of Fingerprint Analysis, 2018
In order to analyze latent fingerprints, suitable exemplars must be recorded in ink, powder, or digitally. Exemplars are recorded as an official record of a person’s identity; to search for a prior arrest record; to compare with evidentiary latent prints; and to input into the Automated Fingerprint Identification System (AFIS) for subsequent searches. Collecting exemplars from deceased individuals can be a challenge due to rigor mortis, putrefaction, maceration, mummification, desiccation, or other consequences of decomposition. This chapter addresses the proper procedures for collecting exemplar prints and the advantages and disadvantages of each method.
Time of Death and Decomposition
Jay Dix in Handbook for Death Scene Investigators, 1999
The determination of time of death, or the interval between the time of death and when the body is found (i.e., postmortem interval), can only be estimated unless there is a witness or a watch breaks during the traumatic incident. The longer the time since death, the greater the chance for error in determining the postmortem interval. There are numerous individual observations which, when used together, provide the best estimate of the time of death. The examiner must check the following: rigor mortis, livor mortis, body temperature, and decompositional changes. A thorough scene investigation is necessary. The environment is the single most important factor in determining the postmortem interval.
From Programs to Systems: Deploying Implementation Science and Practice for Sustained Real World Effectiveness in Services for Children and Families
Published in Journal of Clinical Child & Adolescent Psychology, 2016
The transfer of knowledge of effective practice, especially into “usual care” settings, remains challenging. This article argues that to close this gap we need to recognize the particular challenges of whole-system improvement. We need to move beyond a limited focus on individual programs and experimental research on their effectiveness. The rapidly developing field of implementation science and practice (ISP) provides a particular lens and a set of important constructs that can helpfully accelerate progress. A review of selected key constructs and distinctive features of ISP, including recognizing invisible system infrastructure, co-construction involving active collaboration between stakeholders, and attention to active implementation, supports for providers beyond education and training. Key aspects of an implementation lens likely to be most helpful in sustaining effectiveness include assisting innovators to identify and accommodate the architecture of existing systems, understand the implementation process as a series of distinct but nonlinear stages, identify implementation outcomes as prerequisites for treatment outcomes, and analyse implementation challenges using frameworks of implementation drivers. In complex adaptive systems, how services are implemented may matter more than their specific content, and how services align and adapt to local context may determine their sustained usefulness. To improve implementation-relevant research, we need better process evaluation and cannot rely on experimental methods that do not capture complex systemic contexts. Deployment of an implementation lens may perhaps help to avoid future “rigor mortis,” enabling more productively flexible and integrative approaches to both program design and evaluation.
Presentation andSurvival of Prehospital Apparent Sudden Infant Death Syndrome
Published in Prehospital Emergency Care, 2005
Matthew P. Smith, Amy Kaji, Kelly D. Young, Marianne Gausche-Hill
Background. Prehospital providers are often involved in the resuscitation of apparent sudden infant death syndrome (SIDS) victims; however, data are few on the presentation andoutcome of these patients.Objectives. To describe the presentation anddetermine the survival rate of infants who have an unwitnessed, prehospital arrest consistent with SIDS (apparent SIDS), andto compare the presentation of infants with a final diagnosis of SIDS with those who presented as apparent SIDS but had a different final diagnosis.Methods. This was a secondary analysis of data from a controlled trial whose methodology has been previously described. The setting was two large, urban emergency medical services (EMS) systems of Los Angeles andOrange Counties, California. The population included 113 apparent SIDS victims from the original interventional study who had a prehospital, unwitnessed arrest consistent with SIDS, defined by the scenario of an infant aged ≤12 months being placed to sleep andlater found in full arrest (pulseless andapneic). Data collected included ethnicity, gender, arrest etiology, signs of death (lividity, rigor mortis), prehospital interventions, return of spontaneous circulation (ROSC), arrest rhythm, code 3 transport (lights andsirens), andsurvival to hospital discharge.Results. One hundred ten of 113 apparent SIDS patients had survival data; 0 of 110 (95% CI 0% to 3.3%) survived, although ROSC was achieved in 5%; for three patients data on survival were missing. Arrest rhythms were determined in 94% of the subjects: asystole 87%, pulseless electrical activity (PEA) 8%, andventricular fibrillation 4%. Only 50 of 113 (44%) of the EMS records documented code 3 transport; the remainder of the records were ambiguous. SIDS was the final coroner's diagnosis for 79 of 113 (70%) of the cases. Other causes of death in these apparent SIDS victims included respiratory causes (12%), asphyxiation (3%), abuse (2%), congenital heart disease (2%), sepsis (2%), other (4%), andunknown (5%). Apparent SIDS victims with a final diagnosis of SIDS were more likely to show signs of death (27/79, 34% vs. 5/34, 15%, p = 0.035) andwere less likely to have a rhythm of PEA (4/77, 5% vs. 5/31, 16%, p = 0.08), although the latter result was not statistically significant.Conclusions. Apparent SIDS victims have a dismal prognosis; all infants presenting with apparent SIDS died, even the 30% whose final diagnosis was not SIDS. Given that there were no survivors, new prehospital policies are needed governing the use of lights andsirens, resuscitation decisions including termination of resuscitation, provision of grief support to families, andincident stress debriefing for prehospital personnel.
R ESUSCITATION IN THE O UT-OF-HOSPITAL S ETTING : M EDICAL F UTILITY C RITERIA FOR O N-SCENE P RONOUNCEMENT OF D EATH
Published in Prehospital Emergency Care, 2001
Paul E. Pepe, Robert A. Swor, Joseph P. Ornato, Edward M. Racht, Donald M. Blanton, John K. Griswell, Thomas Blackwell, James Dunford
The complete and irreversible cessation of life is often difficult to determine with complete confidence in the dynamic environment of out-of-hospital emergency care. As a result, resuscitation efforts often are initiated and maintained by emergency medical services (EMS) providers in many hopeless situations. Medical guidelines are reviewed here to aid EMS organizations with respect to decisions about: 1) initiating or waiving resuscitation efforts; 2) the appropriate duration of resuscitation efforts; and 3) recommended procedures for on-scene or prehospital pronouncement of death (termination of resuscitation). In cases of nontraumatic cardiac arrest, few unassailable criteria, other than certain physical signs of irreversible tissue deterioration, exist for determining medical futility at the initial encounter with the patient. Thus, the general medical recommendation is to attempt to resuscitate all patients, adult or child, in the absence of rigor mortis or dependent lividity. Conversely, well-founded guidelines now are available for decisions regarding termination of resuscitation in such patients once they have received a trial of advanced cardiac life support. In practice, however, the final decision to proceed with on-scene pronouncement of death for these patients may be determined more by family and provider comfort levels and the specific on-scene environment. For patients with posttraumatic circulatory arrest, the type of injury (blunt or penetrating), the presence of vital signs, and the electrocardiographic findings are used to determine the futility of initiating or continuing resuscitation efforts. In general, patients who are asystolic on-scene are candidates for on-scene pronouncement, regardless of mechanism. With a few exceptions, blunt trauma patients with a clearly associated mechanism of lethal injury are generally candidates for immediate cessation of efforts once they lose their pulses and respirations. Regardless of the medical futility criteria, specialized training of EMS providers and targeted related testing of operational issues need to precede field implementation of on-scene pronouncement policies. Such policies also must be modified and adapted for local issues and resources. In addition, although the current determinations of medical futility, as delineated here, are important to establish for societal needs, the individual patient's right to live must be kept in mind always as new medical advances are developed.
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