General Considerations

The term "high risk," as applied to autopsy, is generally used to refer to those autopsies in which there is a high risk of transmission of disease to those doing the autopsy. Universal precautions should be used in the performance of all autopsies, because any patient coming to autopsy may have an undiagnosed high-risk condition. Universal precautions include but are not limited to wearing 2 pairs of rubber gloves (ie, "double gloving") for handling tissues or blood, as well as wearing eye protection, cap, gown (or "space suit"), mask, plastic apron, sleeve covers, and shoe covers; these items should be worn by anyone participating in the autopsy dissection. (See also CBRNE - Personal Protective Equipment.)

Frequent changing of the outer gloves is commonly recommended. Cut-resistant stainless steel mesh or fabric gloves are sometimes recommended.¹ They protect against scalpel injury but not against needle puncture. However, because such gloves reduce tactile sensation, some pathologists find them cumbersome.² Latex gloves that are available in supermarkets and that are designed to protect the hands during dishwashing or cleaning are much thicker than surgical gloves or examination gloves. These gloves can represent a compromise between cut-resistant "chain mail" gloves and regular hospital rubber gloves, but they are unsuitable for persons who have an allergy to latex.

In general, anyone in the autopsy room who may come in contact with blood, body fluid, or tissue should wear disposable protective "rubber" gloves. Any surface of the body that might come in contact with blood or body fluid should be protected by impervious material (such as a plastic apron). Face protection should be worn when splashing or splattering of blood or body fluid is possible. A mask is worn to prevent inhalation of aerosols; a face shield is worn to protect the mucous membranes of the eyes, nose, and mouth from exposure to splash. The high-risk infections transmitted by aerosols are tuberculosis, rabies, viral hemorrhagic fever, anthrax, and plague;human immunodeficiency virus (HIV) is not transmitted by aerosols.²

Prosectors should limit their activities to the autopsy table and dissecting area. There should be only 1 blade in the dissection field at any time. A "clean" circulating assistant should be available to obtain additional instruments, to take notes, and to answer the telephone. Specimens for microbiologic culture and cassettes of microscopic sections should be placed in a container; the outside of the container should be free of blood and body fluids from the autopsy. These containers should be put into an impermeable bag for transport to the microbiology and histology laboratories. The paperwork needed to accompany the containers should be free of blood or body fluids. Paperwork that is contaminated by blood or fluid should be replaced by uncontaminated copies of the paperwork before the paperwork leaves the autopsy room.

Needles should not be purposely bent, clipped, recapped, or otherwise manipulated by hand. A puncture-resistant container designed for the disposal of sharp instruments should be within easy reach of the prosector. Needles, syringes, and scalpel blades should be dropped into this container immediately after use. Needles should not be removed from syringes before disposal. Scalpel blades should be removed from their handles with the use of devices designed for this purpose or with a forceps; the tip of the blade should be aimed at the cutting board during removal. Some authorities advocate using one's hand to slip the blade off the scalpel handle; this decreases the possibility that someone struggling to remove a blade may inadvertently propel it into another person. Before leaving the autopsy table, the prosector should remove all scalpel blades from their handles and dispose of the blades immediately after completing the autopsy dissection and sectioning.

Additional measures enhance safety in the autopsy room even further. For most dissections, blunt-tipped scissors may be used instead of a scalpel.³ Tissue may be held for dissection or sectioning with a forceps instead of with the noncutting hand. The ribs may be cut with a large gardening shears-type instrument. A plastic bag or tent may be placed around the mechanical saw while it is being used to cut the skull and spine.⁴

Surgical towels may be placed over the cut edges of the rib cage while the chest is being eviscerated and the thoracic spine and spinal cord cut. When slicing an organ, a sponge or stack of paper towels may be put on top of the organ between the organ and the noncutting hand holding the organ in place while it is being sliced. Scalpels may be placed on a flat surface for the prosector to pick up rather than handed to the prosector.

In general, anyone handling a scalpel or other sharp instrument should shut out distractions while cutting with it; the scalpel should then be set down in plain view in a cleared space. Before moving a sharp instrument, one should announce to all nearby persons that the instrument is being moved. Obtaining microscopic sections, which requires the use of a scalpel, may be done the day after an autopsy, after the tissue intended for sectioning has been fixed.

Additional suggestions for further enhancing safety in the autopsy room are not all practical. Some authors have suggested that the scrub suit worn while performing an autopsy should not be worn outside the autopsy room. This would require that the prosector strip down to his or her underwear before leaving the autopsy room.

Should a needlestick or scalpel cut involving exposure to blood or body fluid occur, the injured person should stop dissecting immediately, allow the wound to bleed freely, wash the wound with soap and water, and then apply disinfectant to the wound. HIV is inactivated by a wide range of disinfectants, including iodophor compounds (such as Betadine), 60% ethanol, 3% hydrogen peroxide, phenolic compounds (such as Lysol), formaldehyde solution (formalin), and sodium hypochlorite (household bleach, Clorox) in a freshly prepared 1:10 dilution in water (final concentration, 0.5%).

Rules and policies are limited in their ability to prevent harm and require mindfulness by those who are supposed to follow them to be effective. Furthermore, situations outside the scope of rules and policies often arise. Thus, perhaps the most important safety measure a prosector can take for preventing transmission of infection at autopsy is to have a safety-first mindset.

Specific Types of High-Risk Autopsies

Many, if not most, high-risk autopsies are known to be such before the autopsy is performed; this is certainly the case in the hospital setting. In North America and Europe, 4 high-risk agents elicit the greatest concern about the transmission of disease during autopsy: HIV, hepatitis C virus (HCV), Mycobacterium tuberculosis, andCreutzfeldt-Jakob prion. Hepatitis B virus (HBV) would be included among these agents of greatest concern except for the fact that almost all healthcare workers are vaccinated against it; anyone performing autopsies certainly should be vaccinated against HBV.

A more complete list of high-risk infections includes rabies, Hantaan virus infection, West Nile Encephalitis,lymphocytic choriomeningitis, human T-cell lymphotropic virus type I, Ebola virus, Lassa fever, South American hemorrhagic fever, the various encephalitis virus infections, dengue fever, yellow fever, Yersinia pestis infection (plague), typhoid fever, Bartonella infections (ie, catscratch disease, trench fever, Oroya fever), tularemia, anthrax,brucellosis, melioidosis, and meningococcal infection.

There is no universal agreement as to which infections are to be considered high risk; some authorities include many more. In general, diseases other than the 4 listed above are rare, and the few that are not rare are not as serious. For example, catscratch disease is usually self-limited and usually requires no therapy.

Methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VREF), multidrug-resistant Pseudomonas aeruginosa, multidrug-resistant Acinetobacter baumannii-haemolyticus, and other multidrug-resistant bacteria that represent normal flora are a concern at autopsy, but the risk that these agents will cause illness in those performing an autopsy is not high. The concern is to avoid spreading these agents outside the autopsy room. To prevent such spread, protective garments that have blood or body fluids on them should be taken off before leaving the autopsy room.

In cases of high-risk infection, evisceration and dissection may be carried out without scalpels, and sectioning may be postponed until the dissected organs have been fixed in 10% formalin; this cannot be done, however, without compromising the autopsy investigation. If large organs such as the liver are not cut into before they are immersed in fixative, many days would be required for the formalin to penetrate to the center of the organ; during that time, autolysis will have obliterated the histology, and the provisional autopsy (PAD) report will be delayed well past the 2 working days required for College of American Pathologists (CAP) laboratory certification. Previous fixation also makes microbiologic cultures impossible.

If mycobacterial infection is discovered, polymerase chain reaction (PCR) testing may be performed on the fixed tissue to determine whether the infection is tuberculosis and, if it is tuberculosis, whether it involves a multidrug-resistant strain. However, these tests are designed for use in blood samples from living patients; they may not work on fixed autolyzed autopsy tissue.

If the presence of pulmonary tuberculosis has already been documented, the lungs may be insufflated with formalin before sectioning. If one is willing to forgo microbiologic culturing and if the local funeral directors permit it, the entire body may be embalmed before autopsy. (Embalmed and exhumed bodies will be discussed in a separate article.)

Autopsy of a Patient With Suspected Creutzfeldt-Jakob Disease

Autopsy of a patient with suspected Creutzfeldt-Jakob disease (CJD) requires unique, special procedures.⁵ CJD is a rare, progressive dementia caused by a transmissible agent that is resistant to 10% formalin, 70% alcohol, phenolic compounds, boiling, and ultraviolet radiation; it is inactivated by 5% sodium hypochlorite, 2 normal sodium hydroxide, 90% formic acid, 0.03% permanganate, and autoclaving at 134° Celsius for 20 minutes or longer.

In cases in which CJD may be present, the autopsy should be limited to the brain and lymphoid tissues. In exceptional cases in which the importance of clinical questions about other organs necessitates that those organs be examined before it is safe to do so, additional tissues may be harvested. Pathologists should consider taking these special precautions in all known cases of CJD, as well as in cases in which there is rapidly progressive dementia, dementia with seizures (especially myoclonic seizures), or dementia associated with cerebellar or lower motor neuron signs. (Autopsy of cases of dementia will be discussed in another article.)

During the autopsy, all tissues and fluids, including running water, should be confined to the autopsy tables. A plastic bag should be placed over the mechanical saw while it is being used to incise the skull and any other bones. At the conclusion of the autopsy, the area of the incision and any other areas of contaminated skin surfaces should be sponged with 5% sodium hypochlorite; the sodium hypochlorite solution should be left on the skin for 10 minutes before being washed off.

After the autopsy, any liquid on the autopsy tables should be disinfected with an equal volume of 5% sodium hypochlorite or 2 normal sodium hydroxide. All instruments should be autoclaved for at least 30 minutes or soaked in 5% sodium hydrochloride or 2 normal sodium hydroxide for 15 minutes. For steel instruments, 2 normal sodium hydroxide is preferable to 5% sodium hypochlorite. All gowns, gloves, plastic aprons, and other disposable supplies should be incinerated or autoclaved before disposal. The funeral home should be notified of the high-risk nature of the case.

Scout blocks of the midfrontal cortex, the globus pallidus, and the cerebellum should be removed from the fresh brain and placed in 10% formalin for fixation; the tissues should remain in 10% formalin for a period of 2 to 7 days. The remaining brain may be fixed by immersion in 10% formalin. After fixation, the scout blocks should be decontaminated for 1 hour in 95% formic acid before a final fixation for 2 days in 10% formalin; they should then be embedded in paraffin. This fixation procedure essentially inactivates the agent, and the blocks may then be handled in a routine fashion.

If the scout blocks reveal pathology consistent with CJD, the brain, which has been stored in 10% formalin, may be burned and the container decontaminated, as described above. If CJD is not found in the scout blocks, the remaining brain tissue may be processed in a routine fashion for evaluation of possible Alzheimer disease or other dementing disorders.