Minimizing aerosol bone dust during autopsies

Abstract

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.

Covid-19

“…17,18 Other oscillating saw aerosol reduction techniques to consider include moistening the saw blade before cutting, using autopsy tables with built-in ventilation, tenting plastic around the decedent's neck and head to entrap aerosols, and wearing a HEPA-filtered PAPR rather than N95 mask. [46][47][48][49] As in the current presented case, other general splash and aerosol reduction techniques (eg, eschewing use of vacuum assisted aspirator, sink tissue grinder, or hose) are also advised. Autopsy protocol recommendations are summarized in Table 2.…”

“…[38][39][40][41][42] However, the most likely aerosol-generating autopsy procedure is use of powered oscillating bone saws, particularly during brain removal. [46][47][48][49][50] High densities of aerosolized particles are generated in the region of the saw placing the user at risk. While N95 respirator masks physically filter 95% of particles at least 1 μm in size from the inspired air, CDC and OSHA guidelines nonetheless suggest avoiding use of an oscillating bone saw at autopsy in cases of suspected/confirmed COVID-19.…”

Use of post-mortem chest computed tomography in Covid-19 pneumonia

“…Based on the Biological Agents Ordinance, the Committee on Biological Agents has classified SARS-CoV-2 as a risk group 3 pathogen (high individual risk, low community risk) and provided special instructions for managing infected corpses [27]. Nonetheless, biosafety standards in morgues are not on the same level as those applied for infection control in laboratories and clinical environments [5,6].…”

New autopsy technique in COVID-19 positive dead bodies: opening the thoracic cavity with an outlook to reduce aerosol spread

“…This process of dissection of the lungs and large airways by opening the thoracic cavity is an area of extreme concern while dealing with death cases due to respiratory viruses like COVID-19. Eventually, the forensic medicine experts and the entire mortuary staff become susceptible to these aerosols 22 23. Opening the skull bone also results in the spread of infection.…”

“…Eventually, the forensic medicine experts and the entire mortuary staff become susceptible to these aerosols. 22 23 Opening the skull bone also results in the spread of infection. However, using a vacuum saw can somewhat reduce the chance of aerosol spread but only to a certain extent.…”