[Sawdust in autopsies: production, spreading, and contamination]

Particulate matter emissions during autopsies: a method to reduce exposure

Particulate matter emitted during autopsies can serve as a vector for numerous viruses or bacteria and can lead to infections. Reducing the exposure of those particles in indoor working environments is, therefore, an important issue. To assess the health risk for employees in forensic medicine, we measure particulate matter in the ambient air during autopsies by using an aerosol spectrometer. The autopsies were performed with either an ordinary oscillating saw or an adapted saw with a suction unit. The particle emissions from both saws were compared to each other in order to evaluate whether a technical adaption leads to a particle reduction. Furthermore, the particle exposure reduction by wearing a face mask and variations in the background concentration in the room were analyzed. High particle concentrations were measured while using the ordinary saw. By using the adapted saw or wearing a face mask, the particle exposure could mostly be avoided. On the majority of the working days, an increase in the background concentration could be observed. Based on this knowledge, the use of a proper suction unit and wearing a face mask during autopsies is necessary. Besides, it is important to have sufficient ventilation in the room so that long-lasting high background concentrations can be prevented.

[Autoptical display of the nasopharyngeal space in cases of suspected SARS-Co2 infection]

This paper deals with a dissection technique in order to display the nasopharyngeal space. It consists of a parafrontal saw cut through the base of the skull at the level of the sella turcica. In this way the ventral part of the nasopharyngeal space can be separated from the cervical spine and the posterior base of the skull within an anatomically preformed border region. Apart from a comprehensive overview of the nasopharyngeal space, this technique also enables samples to be correctly taken. The time required takes approximately 2-3 min, the external appearance of the deceased is not affected and the preparation of the body is not complicated.

Robotic-Assisted Surgery for Cadaveric Skull Opening: A New Method of Autopsy Procedure

Background: Sawing of bone is an essential part of an autopsy procedure. An oscillating saw always generates noise, fine infectious dust particles, and the possibility of traumatic injuries, all of which can induce occupational hazard risks to autopsy workers, especially during the COVID-19 pandemic. Objectives: The first goal of this study was to explore the production of noise and bone dust emission, comparing an oscillating saw and a robotic autopsy saw during an autopsy. The second goal was to evaluate the performance of a new robotic autopsy method, used during skull opening. The third goal was to encourage mortuary workers to use robotic technology during the autopsy procedure to protect us away from occupational injuries as well as airborne infections. Materials and Methods: The experiments involved a comparison of noise levels and aerosol production during skull cutting between the oscillating saw and the robotic autopsy saw. Results: The results confirmed that noise production from the robotic autopsy saw was lower than the oscillating saw. However, the bone dust levels, produced by the robotic autopsy saw, were greater than the oscillating saw, but were not greater than the dust concentrations which were present before opening the skull. Conclusions: The use of a new robotic system might be an alternative choice for protecting against occupational damage among the healthcare workers. Further research might attempt to consider other healthcare problems which occur in the autopsy workplace and apply the robotic-assisted technology in autopsy surgery.

Minimizing aerosol bone dust during autopsies

When sawing bone for medical or medico-legal procedures, fine, airborne dust is produced (aerosols) that can pose a health hazard when inhaled. The aim of this study was to determine the influence of saw blade frequency and contact load, bone condition, test environment, and saw blade type, on the production of aerosol particles. A custom test setup was designed, manufactured and used in 8 bone sawing experiments, using a particle counter to determine the production of aerosol particles while varying the 5 chosen parameters. The number of counted particles was highest with higher saw blade frequencies, lower saw blade contact loads, in dry completely skeletonized bone compared to fresh bone, and using an electrical oscillating saw compared to hand-sawing. Under all conditions, the high amount of aerosol counted posed potential health risks. The ventilation system that we tested was adequate in removing the produced particles, but these high-tech systems are not always available in developing countries or emergency situations. The production of aerosols can be reduced by optimizing the sawing parameters. However, even the lowest number of aerosol particles counted during the current study was high enough to cause potential health risks to practitioners. Safety precautions should be taken, such as external ventilation, proper breathing gear, and adequate protocols, to truly minimize the risk in all bone sawing scenarios.

Aerosol production during autopsies: The risk of sawing in bone

When sawing during autopsies on human remains, fine dust is produced, which consists of particles of sizes that may fall within the human respirable range, and can act as vectors for pathogens. The goal of this study was to explore the potential effects of saw blade frequency and saw blade contact load on the number and size of airborne bone particles produced. The methodology involved the use of an oscillating saw with variable saw blade frequencies and different saw blade contact loads on dry human femora. Released airborne particles were counted per diameter by a particle counter inside a closed and controlled environment. Results corroborated with the hypotheses: higher frequencies or lower contact loads resulted in higher numbers of aerosol particles produced. However, it was found that even in the best-case scenario tested on dry bone, the number of aerosol particles produced was still high enough to provide a potential health risk to the forensic practitioners. Protective breathing gear such as respirators and biosafety protocols are recommended to be put into practice to protect forensic practitioners from acquiring pathologies, or from other biological hazards when performing autopsies.

[Clinical autopsies. Practical approach, legal foundations and ethical considerations]

Only an autopsy can demonstrate topographical and morphological circumstances in detail and correlate the clinical and autopsy findings based on the examination of all organs. The practical approach in a fatality is described based on the example of the Lüdenscheid Hospital. A uniform legal regulation for dealing with corpses does not exist in Germany. There are two approaches to the question under which circumstances a clinical autopsy is allowed: the extended permission solution and the objection solution. Whether a clinical autopsy can be carried out is decided by the medical specialist selected on application. Autopsies can be necessary from insurance or administrative legal grounds or in the case of an anatomical autopsy is decided by the persons themselves. In order to guarantee the quality of an autopsy it is necessary to use a standardized approach with evaluation and assessment of the results, for example using a quality assurance protocol and the production of an autopsy report. Using this approach important information can be gained not only on the accuracy of the main diagnosis and cause of death but also on additional diseases, response to therapy and the course of the disease and under circumstances can lead to modifications in the approach.

Anatomic laboratory and forensic aspects of biological threat agents

Anatomic pathology of surgical and cytologic samples and forensic autopsies is a critical component of our defense against biological terrorism. In many instances, rapid, valuable diagnosis may be obtained by the proper immediate use of the anatomic pathology laboratory. Included in this field is the work of medical examiners and coroners, who are essential public health partners for terrorism preparedness and response. The investigation of sudden, suspicious, violent, unattended, and unexplained deaths may provide the first clue to a deliberate biological attack. Medicolegal autopsies are essential to making organism-specific diagnoses in deaths caused by biological terrorism.

[Hygienic requirements for biopsy and autopsy diagnostics]

In former times autopsies were the main task of a pathologist and therefore the most frequent source of infection but nowadays cytological and biopsy investigations dominate the pathologist's work. Usually the time interval between the extraction of a specimen, its transport into the laboratory and return of the report is no longer than a few hours. Consequently the staff must often handle unfixed or insufficiently fixed material. This and the occurrence of new infectious diseases, e.g. AIDS and TSE (transmissible spongiform encephalopathies), makes it necessary to analyse and perhaps even change the work in respect to hygiene risks and demands for permanent protection against infection. First of all the risks of infection and the common measures of protection from infections for the staff in biopsy and autopsy departments will be described. Subsequently suggestions to reduce infectious risks in special activities will be presented. The examination of frozen sections or intraoperative biopsy material and the handling of specimens possibly contaminated by HIV and TSE will be considered separately.

Biosafety considerations for autopsy

An autopsy may subject prosectors and others to a wide variety of infectious agents, including bloodborne and aerosolized pathogens such as human immunodeficiency virus, hepatitis B and C viruses, and Mycobacterium tuberculosis. Other hazards include toxic chemicals (e.g., formalin, cyanide, and organophosphates) and radiation from radionuclides used for patient therapy and diagnosis. These risks can be substantially mitigated through proper assessment, personal protective equipment, appropriate autopsy procedures, and facility design.

On the contamination of ambient air by preparations carried out with a band-saw

The aim was to evaluate contamination by bone-dust and formaldehyde when using a band-saw for preparations of the base of the skull and the cervical vertebral spine (stationary band-saw, 1400 upm, saw blade with 160 saw teeth/m; distances 19-26 cm, time intervals 55-90 s). The asservation of bone particles was done with adhesive microscopic slides and calcium-specific staining by alizarin-red. The quantification of air contamination was carried out with micrometry and a particle-counter. Dräger-tubes 0.2/9 were utilized for estimation of formaldehyde. The band-saw did not produce high amounts of bone-dust with suspension power. Nevertheless, 75% of the particles ranged below 5 microns in size and were respirable. Contamination decreased with an increasing height above the floor. A massive flow of particles was observed during the first minutes of sawing. The bone-dust spread some metres away. The formaldehyde levels ranged throughout between 0.5 and also over 5 ppm (MAK = 0.5 ppm). This fact makes clear an intensive contamination of the air. Therefore, a ventilation directed to the floor is necessary when a band-saw is used, as well as breathing masks and safety-goggles.