Minimizing aerosol bone dust during autopsies

Diathermy and bone sawing are high aerosol yield procedures

Aims

Orthopaedic surgery uses many varied instruments with high-speed, high-impact, thermal energy and sometimes heavy instruments, all of which potentially result in aerosolization of contaminated blood, tissue, and bone, raising concerns for clinicians' health. This study quantifies the aerosol exposure by measuring the number and size distribution of the particles reaching the lead surgeon during key orthopaedic operations.

Methods

The aerosol yield from 17 orthopaedic open surgeries (on the knee, hip, and shoulder) was recorded at the position of the lead surgeon using an Aerodynamic Particle Sizer (APS; 0.5 to 20 μm diameter particles) sampling at 1 s time resolution. Through timestamping, detected aerosol was attributed to specific procedures.

Results

Diathermy (electrocautery) and oscillating bone saw use had a high aerosol yield (> 100 particles detected per s) consistent with high exposure to aerosol in the respirable range (< 5 µm) for the lead surgeon. Pulsed lavage, reaming, osteotome use, and jig application/removal were medium aerosol yield (10 to 100 particles s-1). However, pulsed lavage aerosol was largely attributed to the saline jet, osteotome use was always brief, and jig application/removal had a large variability in the associated aerosol yield. Suctioning (with/without saline irrigation) had a low aerosol yield (< 10 particles s-1). Most surprisingly, other high-speed procedures, such as drilling and screwing, had low aerosol yields.

Conclusion

This work suggests that additional precautions should be recommended for diathermy and bone sawing, such as enhanced personal protective equipment or the use of suction devices to reduce exposure.

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

AIMS

After the advent of the COVID-19 pandemic, most countries have modified some of their health-related regulations. However, this has not been in the case of the postmortem of deceased because it has a legal aspect. Thus, the healthcare providers knowingly or unknowingly faced the threat of COVID-19 exposure from those dead bodies. To introduce an autopsy technique that reduces the droplet spreads, especially in those mortuaries where the biosafety mechanism is not highly equipped.

METHODS

The validity of the new incision was achieved through the calculation of the Scale Content Validity Index (SCVI) taking inputs from 17 forensic specialists. The subjects for the new technique were selected from the patients who were RTPCR positive for COVID-19 or clinically or radiologically showing features of COVID-19.

RESULTS

The dissection procedure was finalised by achieving the SCVI at 0.92. The chest cavity was approached through the abdominal cavity by opening the diaphragm and dissecting out the contents of the chest using a long blade knife.

CONCLUSIONS

The advantage of this approach is that the autopsy surgeon and pathologists do not have to open the chest cavity by dissecting the Sternum, and hence the chance of droplet infection becomes almost nil. This technique is complete, simple, less time-consuming and conducive for sample collection, and even reduces the possibility of body fluid seepage following a postmortem examination.

Prevention of the spread of infection during highly infectious autopsy using a craniotomy box

In cranial autopsies, the post-mortem examination requires the use of a saw for the removal of the skull cap. In these procedures, sawing of bone becomes a critical source of infectious aerosols which spread instantaneously in the immediate environment, generating liquid aerosols including droplets of cerebrospinal fluid and blood, and leading to exposure of all autopsy personnel. In high-risk cases like prion disease, tuberculosis, severe acute respiratory syndrome (SARS), COVID-19, etc. where the skull would require sawing, the prime concern is the saw operator's exposure to these pathogens. Therefore, the author suggests the use of an ingenious ergonomic semi-circular craniotomy box during skull cap and brain removal in the autopsy procedure to successfully prevent the contamination of the entire autopsy hall. A transparent acrylic plastic box has been customized, which is semi-circular in shape having three walls, one semi-circular dome without a floor, a front wall with adjustable zipper closure, and a hind wall with circular holes with sleeves made of 5-layer fabrics. The dome contains one outlet for a vacuum suction pipe on the side, two holes on each side of the dome with non-woven fabric arms for the saw operator, and assistants' arms for performing skull opening procedures. The use of this box allowed the author to prevent and limit the spread of the generation of infectious aerosols in the autopsy hall as the bone dust collected in the vacuum ensures the safety of autopsy surgeons.

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

Background and aim

COVID-19 is an extremely challenging disease, both from a clinical and forensic point of view, and performing autopsies of COVID-19 deceased requires adequately equipped sectorial rooms and exposes health professionals to the risk of contagion. Among one of the categories that are most affected by SARS-Cov-2 infection are the elderly residents. Despite the need for prompt diagnoses, which are essential to implement all isolation measures necessary to contain the infection spread, deceased subjects in long-term care facilities are still are often diagnosed post-mortem. In this context, our study focuses on the use of post-mortem computed tomography for the diagnosis of COVID-19 infection, in conjunction with post-mortem swabs. The aim of this study was to assess the usefulness of post-mortem whole CT-scanning in identifying COVID-19 pneumonia as a cause of death, by comparing chest CT-findings of confirmed COVID-19 fatalities to control cases.

Materials and methods

The study included 24 deceased subjects: 13 subjects coming from long-term care facility and 11 subjects died at home. Whole body CT scans were performed within 48 h from death in all subjects to evaluate the presence and distribution of pulmonary abnormalities typical of COVID-19-pneumonia, including: ground-glass opacities (GGO), consolidation, and pleural effusion to confirm the post-mortem diagnosis.

Results

Whole-body CT scans was feasible and allowed a complete diagnosis in all subjects. In 9 (69%) of the 13 cases from long-term care facility the cause of death was severe COVID 19 pneumonia, while GGO were present in 100% of the study population.

Conclusion

In the context of rapidly escalating COVID-19 outbreaks, given that laboratory tests for the novel coronavirus is time-consuming and can be falsely negative, the post-mortem CT can be considered as a reliable and safe modality to confirm COVID-19 pneumonia. This is especially true for specific postmortem chest CT-findings that are rather characteristic of COVID-19 fatalities.

COVID-19: Postmortem Diagnostic and Biosafety Considerations

As a result of the 2019 novel human coronavirus (COVID-19) global spread, medical examiner/coroner offices will inevitably encounter increased numbers of COVID-19-infected decedents at autopsy. While in some cases a history of fever and/or respiratory distress (eg, cough or shortness of breath) may suggest the diagnosis, epidemiologic studies indicate that the majority of individuals infected with COVID-19 develop mild to no symptoms. Those dying with-but not of-COVID-19 may still be infectious, however. While multiple guidelines have been issued regarding autopsy protocol in cases of suspected COVID-19 deaths, there is some variability in the recommendations. Additionally, limited recommendations to date have been issued regarding scene investigative protocol, and there is a paucity of publications characterizing COVID-19 postmortem gross and histologic findings. A case of sudden unexpected death due to COVID-19 is presented as a means of illustrating common autopsy findings, as well as diagnostic and biosafety considerations. We also review and summarize the current COVID-19 literature in an effort to provide practical evidence-based biosafety guidance for medical examiner-coroner offices encountering COVID-19 at autopsy.