Anautopsy (also referred to aspost-mortem examination,obduction,necropsy,[Note 1] orautopsia cadaverum) is asurgical procedure that consists of a thoroughexamination of acorpse bydissection to determine the cause, mode, and manner ofdeath; or the exam may be performed to evaluate anydisease orinjury that may be present for research or educational purposes. The termnecropsy is generally used for non-human animals.
Autopsies are usually performed by a specialized medical doctor called apathologist. Only a small portion of deaths require an autopsy to be performed, under certain circumstances. In most cases, amedical examiner orcoroner can determine the cause of death.
If it is an infant, determinelive birth and viability
For example, a forensic autopsy is carried out when thecause of death may be a criminal matter, while a clinical or academic autopsy is performed to find the medical cause of death and is used in cases of unknown or uncertain death, or for research purposes. Autopsies can be further classified into cases where an external examination suffices, and those where the body is dissected and an internal examination is conducted. Permission fromnext of kin may be required for internal autopsy in some cases. Once an internal autopsy is complete, the body is reconstituted by sewing it back together.
The term "autopsy" derives from theAncient Greek αὐτοψίαautopsia, "to see for oneself", derived from αὐτός (autos, "oneself") and ὄψις (opsis, "sight, view").[1] The word has been in use since around the 17th century.[2]
The principal aims of an autopsy are to determine thecause of death, mode of death,manner of death, the state of health of the person before he or she died, and whether anymedical diagnosis and treatment before death were appropriate.[6] In mostWestern countries the number of autopsies performed in hospitals has been decreasing every year since 1955. Critics, including pathologist and formerJAMAeditorGeorge D. Lundberg, have charged that the reduction in autopsies is negatively affecting the care delivered in hospitals, because when mistakes result in death, they are often not investigated and lessons, therefore, remain unlearned. When a person has permitted an autopsy in advance of their death, autopsies may also be carried out for the purposes of teaching or medical research. An autopsy is usually performed in cases of sudden death, where a doctor is not able to write a death certificate, or when death is believed to result from anunnatural cause. These examinations are performed under a legal authority (medical examiner,coroner, orprocurator fiscal) and do not require the consent of relatives of the deceased. The most extreme example is the examination ofmurder victims, especially when medical examiners are looking for signs of death or the murder method, such asbullet wounds and exit points, signs ofstrangulation, or traces ofpoison.Some religions includingJudaism andIslam usually discourage the performing of autopsies on their adherents.[7] Organizations such asZAKA in Israel andMisaskim in the United States generally guide families on how to ensure that an unnecessary autopsy is not made.Autopsies are used in clinical medicine to identify amedical error or a previously unnoticed condition that may endanger the living, such asinfectious diseases or exposure tohazardous materials.[8]A study that focused onmyocardial infarction (heart attack) as a cause of death found significant errors of omission and commission,[9] i.e. a sizable number of cases ascribed tomyocardial infarctions (MIs) were not MIs and a significant number of non-MIs were MIs.
Asystematic review of studies of the autopsy calculated that in about 25% of autopsies, a major diagnostic error will be revealed.[10] However, this rate has decreased over time and the study projects that in a contemporary US institution, 8.4% to 24.4% of autopsies will detect major diagnostic errors.
A largemeta-analysis suggested that approximately one-third ofdeath certificates are incorrect and that half of the autopsies performed produced findings that were not suspected before the person died.[11] Also, it is thought that over one-fifth of unexpected findings can only be diagnosedhistologically,i.e., bybiopsy or autopsy, and that approximately one-quarter of unexpected findings, or 5% of all findings, are major and can similarly only be diagnosed from tissue.
One study found that (out of 694 diagnoses) "Autopsies revealed 171 missed diagnoses, including 21 cancers, 12 strokes, 11 myocardial infarctions, 10 pulmonary emboli, and 9 endocarditis, among others".[12]
Focusing onintubated patients, one study found "abdominal pathologic conditions – abscesses, bowel perforations, or infarction – were as frequent aspulmonary emboli as a cause of class I errors. While patients with abdominal pathologic conditions generally complained of abdominal pain, results of an examination of the abdomen were considered unremarkable in most patients, and the symptom was not pursued".[13]
Medico-legal orforensic orcoroner's autopsies seek to find the cause and manner of death and to identify the decedent.[14] They are generally performed, as prescribed by applicable law, in cases of violent, suspicious or sudden deaths, deaths without medical assistance, or during surgical procedures.[14]
Clinical orpathological autopsies are performed to diagnose a particular disease or for research purposes. They aim to determine, clarify, or confirm medicaldiagnoses that remained unknown or unclear before the patient's death.[14]
Anatomical oracademic autopsies are performed by students of anatomy for study purposes only.
Virtual ormedical imaging autopsies are performed utilizing imaging technology only, primarily magnetic resonance imaging (MRI) and computed tomography (CT).[15]
A forensic autopsy is used to determine the cause, mode, and manner of death.
Forensic science involves the application of the sciences to answer questions of interest to the legal system.
Medical examiners attempt to determine the time of death, the exact cause of death, and what, if anything, preceded the death, such as a struggle. A forensic autopsy may include obtaining biological specimens from the deceased for toxicological testing, including stomach contents.Toxicology tests may reveal the presence of one or more chemical "poisons" (all chemicals, insufficient quantities, can be classified as a poison) and their quantity. Because post-mortem deterioration of the body, together with the gravitational pooling of bodily fluids, will necessarily alter the bodily environment, toxicology tests may overestimate, rather than underestimate, the quantity of the suspected chemical.[16]
Following an in-depth examination of all theevidence, a medical examiner orcoroner will assign amanner of death from the choices proscribed by the fact-finder's jurisdiction and will detail the evidence on the mechanism of the death.
Pathologist performing a human dissection of the abdominal and thoracic organs in an autopsy room
Clinical autopsies serve two major purposes. They are performed to gain more insight intopathological processes and determine what factors contributed to a patient's death. For example, material for infectious disease testing can be collected during an autopsy.[17] Autopsies are also performed to ensure the standard of care at hospitals. Autopsies can yield insight into how patient deaths can be prevented in the future.
Within the United Kingdom, clinical autopsies can be carried out only with the consent of the family of the deceased person, as opposed to a medico-legal autopsy instructed by a Coroner (England & Wales) or Procurator Fiscal (Scotland), to which the family cannot object.[18]
Over time, autopsies have not only been able to determine the cause of death, but have also led to discoveries of various diseases such as fetal alcohol syndrome, Legionnaire's disease, and even viral hepatitis.
Academic autopsies are performed by students of anatomy for the purpose of study, giving medical students and residents firsthand experience viewing anatomy and pathology. Postmortem examinations require the skill to connect anatomic and clinical pathology together since they involve organ systems and interruptions from ante-mortem and post-mortem. These academic autopsies allow for students to practice and develop skills in pathology and become meticulous in later case examinations.[19]
Virtual autopsies are performed using radiographic techniques which can be used in post-mortem examinations for a deceased individual.[20] It is an alternative to medical autopsies, where radiographs are used, for example,Magnetic resonance imaging (MRI) and Computed tomography (CT scan) which produce radiographic images in order to determine the cause of death, the nature, and the manner of death, without dissecting the deceased. It can also be used in the identification of the deceased.[21] This method is helpful in determining the questions pertaining to an autopsy without putting the examiner at risk of biohazardous materials that can be in an individual's body.
In 2004 in England and Wales, there were 514,000 deaths, of which 225,500 werereferred to the coroner. Of those, 115,800 (22.5% of all deaths) resulted in post-mortem examinations and there were 28,300inquests, 570 with a jury.[22]
The rate of consented (hospital) autopsy in the UK and worldwide has declined rapidly over the past 50 years. In the UK in 2013, only 0.7% of inpatient adult deaths were followed by consented autopsy.[23]
The autopsy rate inGermany is below 5% and thus much lower than in other countries in Europe. The governmental reimbursement is hardly sufficient to cover all the costs, so the medical journalDeutsches Ärzteblatt, issued by theGerman Medical Association, makes the effort to raise awareness regarding the underfinancing of autopsies. The same sources stated that autopsy rates inSweden andFinland reach 20 to 30%.[24]
In the United States, autopsy rates fell from 17% in 1980 to 14% in 1985[25] and 11.5% in 1989,[26] although the figures vary notably from county to county.[27]
Cadaver dissection tables are similar to those used in medical or forensic autopsies.
The body is received at a medical examiner's office, municipal mortuary, or hospital in abody bag or evidence sheet. A new body bag is used for each body to ensure that onlyevidence from that body is contained within the bag. Evidence sheets are an alternative way to transport the body. An evidence sheet is asterile sheet that covers the body when it is moved. If it is believed there may be any significant evidence on the hands, for example,gunshot residue or skin under thefingernails, a separate paper sack is put around each hand and taped shut around the wrist.
At many institutions, the person responsible for handling, cleaning, and moving the body is called adiener, theGerman word forservant. In the UK this role is performed by an Anatomical Pathology Technician (APT), who will also assist the pathologist in eviscerating the body and reconstruction after the autopsy. After the body is received, it is firstphotographed. The examiner then notes the kind of clothes - if any - and their position on the body before they are removed. Next, any evidence such as residue, flakes of paint, or other material is collected from the external surfaces of the body.Ultraviolet light may also be used to search body surfaces for any evidence not easily visible to the naked eye. Samples ofhair,nails, and the like are taken, and the body may also beradiographically imaged. Once the external evidence is collected, the body is removed from the bag, undressed, and anywounds present are examined. The body is then cleaned, weighed, and measured in preparation for the internal examination.
In some countries,[28][29]e.g., Scotland, France, Germany, Russia, and Canada, an autopsy may comprise an external examination only. This concept is sometimes termed a "view and grant". The principle behind this is that the medical records, history of the deceased and circumstances of death have all indicated as to the cause and manner of death without the need for an internal examination.[30]
If not already in place, a plastic or rubber brick called a "head block" is placed under the shoulders of the corpse; hyperflexion of the neck makes the spine arch backward while stretching and pushing thechest upward to make it easier to incise. This gives the APT, or pathologist, maximum exposure to thetrunk. After this is done, the internal examination begins. The internal examination consists of inspecting theinternal organs of the body bydissection for evidence oftrauma or other indications of the cause of death. For the internal examination there are a number of different approaches available:
a large and deep Y-shaped incision can be made starting at the top of each shoulder and running down the front of the chest, meeting at the lower point of thesternum (breastbone).
a curved incision made from the tips of each shoulder, in a semi-circular line across the chest/decolletage, to approximately the level of the second rib, curving back up to the opposite shoulder.
a single vertical incision is made from the sternal notch at the base of the neck.
a U-shaped incision is made at the tip of both shoulders, down along the side of the chest to the bottom of the rib cage, following it. This is typically used on women and during chest-only autopsies.
There is no need for any incision to be made, which will be visible after completion of the examination when the deceased is dressed in a shroud.In all of the above cases, the incision then extends all the way down to thepubic bone (making a deviation to either side of the navel) and avoiding, where possible, transecting any scars that may be present.
Bleeding from the cuts is minimal, or non-existent because the pull ofgravity is producing the onlyblood pressure at this point, related directly to the complete lack of cardiac functionality. However, in certain cases, there is anecdotal evidence that bleeding can be quite profuse, especially in cases ofdrowning.
At this point, shears are used to open the chest cavity. The examiner uses the tool to cut through the ribs on the costal cartilage, to allow the sternum to be removed; this is done so that the heart and lungs can be seenin situ and that the heart – in particular, thepericardial sac – is not damaged or disturbed from opening. A PM 40 knife is used to remove the sternum from the soft tissue that attaches it to the mediastinum. Now thelungs and the heart are exposed. The sternum is set aside and will eventually be replaced at the end of the autopsy.
At this stage, theorgans are exposed. Usually, the organs are removed in a systematic fashion. Making a decision as to what order the organs are to be removed will depend highly on the case in question. Organs can be removed in several ways: The first is theen masse technique of Letulle whereby all the organs are removed as one large mass. The second is the en bloc method of Ghon. The most popular in the UK is a modified version of this method, which is divided into four groups of organs. Although these are the two predominant evisceration techniques, in the UK variations on these are widespread.
One method is described here: The pericardial sac is opened to view the heart. Blood for chemical analysis may be removed from theinferior vena cava or the pulmonary veins. Before removing the heart, thepulmonary artery is opened in order to search for a blood clot. The heart can then be removed by cutting the inferior vena cava, the pulmonary veins, theaorta and pulmonary artery, and thesuperior vena cava. This method leaves the aortic arch intact, which will make things easier for the embalmer. The left lung is then easily accessible and can be removed by cutting thebronchus, artery, and vein at thehilum. The right lung can then be similarly removed. The abdominal organs can be removed one by one after first examining their relationships and vessels.
Most pathologists, however, prefer the organs to be removed all in one "block". Using dissection of the fascia, blunt dissection; using the fingers or hands and traction; the organs are dissected out in one piece for further inspection and sampling. During autopsies of infants, this method is used almost all of the time. The various organs are examined, weighed and tissue samples in the form of slices are taken. Even majorblood vessels are cut open and inspected at this stage. Next, thestomach and intestinal contents are examined and weighed. This could be useful to find the cause and time of death, due to the natural passage of food through the bowel during digestion. The more area empty, the longer the deceased had gone without a meal before death.
A brain autopsy demonstrating signs ofmeningitis. Theforceps (center) are retracting thedura mater (white). Underneath the dura mater are theleptomeninges, which appear to beedematous and have multiple small hemorrhagic foci.Autopsy of a brain after sectioning, showing a normal brain with the cerebrum cut in coronal sections, and the cerebellum, pons and medulla cut in horizontal sections. Standard sections for microscopic examination are annotated.
The body block that was used earlier to elevate the chest cavity is now used to elevate the head. To examine thebrain, an incision is made from behind one ear, over the crown of the head, to a point behind the other ear. When the autopsy is completed, the incision can be neatly sewn up and is not noticed when the head is resting on a pillow in an open casketfuneral. Thescalp is pulled away from theskull in two flaps with the front flap going over the face and the rear flap over the back of the neck. The skull is then cut with a circular (or semicircular) bladed reciprocating saw to create a "cap" that can be pulled off, exposing the brain. The brain is then observed in situ. Then the brain's connections to the cranial nerves andspinal cord are severed, and the brain is lifted out of the skull for further examination. If the brain needs to be preserved before being inspected, it is contained in a large container of formalin (15 percent solution offormaldehyde gas in bufferedwater) for at least two, but preferably four weeks. This not only preserves the brain, but also makes it firmer, allowing easier handling without corrupting the tissue.
An important component of the autopsy is the reconstitution of the body such that it can be viewed, if desired, by relatives of the deceased following the procedure. After the examination, the body has an open and emptythoracic cavity with chest flaps open on both sides; the top of the skull is missing, and the skull flaps are pulled over the face and neck. It is unusual to examine the face, arms, hands or legs internally.
In the UK, following theHuman Tissue Act 2004 all organs and tissue must be returned to the body unless permission is given by the family to retain any tissue for further investigation. Normally the internal body cavity is lined with cotton, wool, or a similar material, and the organs are then placed into a plastic bag to prevent leakage and are returned to the body cavity. The chest flaps are then closed and sewn back together and the skull cap is sewed back in place. Then the body may be wrapped in ashroud, and it is common for relatives to not be able to tell the procedure has been done when the body is viewed in afuneral parlor afterembalming.
Cavitation at gross pathology of an old stroke in the left posterior parietal lobe
An autopsy ofstroke may be able to establish the time taken from the onset of cerebral infarction to the time of death.
Various microscopic findings are present at times from infarction as follows:[31]
Histopathology at high magnification of a normal neuron, and an ischemic stroke at approximately 24 hours onH&E stain: The neurons become hypereosinophilic and there is an infiltrate ofneutrophils. There is slight edema and loss of normal architecture in the surroundingneuropil.
Around 3000 BCE,ancient Egyptians were one of the first civilizations to practice the removal and examination of the internal organs of humans in the religious practice ofmummification.[1][32]
Autopsies that opened the body to determine the cause of death were attested at least in the early third millennium BCE, although they were opposed in many ancient societies where it was believed that the outward disfigurement of dead persons prevented them from entering theafterlife[33] (as with the Egyptians, who removed the organs through tiny slits in the body).[1] Notable Greek autopsists wereErasistratus andHerophilus of Chalcedon, who lived in 3rd century BCEAlexandria, but in general, autopsies were rare in ancient Greece.[33] In 44 BCE,Julius Caesar was the subject of an official autopsy afterhis murder by rival senators, the physician's report noting that the second stab wound Caesar received was the fatal one.[33] Julius Caesar had been stabbed a total of 23 times.[34] By around 150 BCE,ancient Roman legal practice had established clear parameters for autopsies.[1] The greatest ancient anatomist wasGalen (CE 129–c. 216), whose findings would not be challenged until theRenaissance over a thousand years later.[35]
Ibn Tufail has elaborated on autopsy in his treatise calledHayy ibn Yaqzan andNadia Maftouni, discussing the subject in an extensive article, believes him to be among the early supporters of autopsy andvivisection.[36]
The dissection of human remains for medical or scientific reasons continued to be practiced irregularly after the Romans, for instance by the Arab physiciansAvenzoar andIbn al-Nafis. In Europe they were done with enough regularity to become skilled, as early as 1200, and successful efforts to preserve the body, by filling the veins with wax and metals.[35] Until the 20th century,[35] it was thought that the modern autopsy process derived from theanatomists of theRenaissance.Giovanni Battista Morgagni (1682–1771), celebrated as the father ofanatomical pathology,[37] wrote the first exhaustive work on pathology,De Sedibus et Causis Morborum per Anatomen Indagatis (The Seats and Causes of Diseases Investigated by Anatomy, 1769).[1]
In 1543,Andreas Vesalius conducted a public dissection of the body of a former criminal. He asserted and articulated the bones, this became the world's oldest surviving anatomical preparation. It is still displayed at the Anatomical Museum at the University of Basel.[38]
The 19th-century medical researcherRudolf Virchow, in response to a lack of standardization of autopsy procedures, established and published specific autopsy protocols (one such protocol still bears his name). He also developed the concept of pathological processes.[39]
During the turn of the 20th century, theScotland Yard created the Office of the Forensic Pathologist, a medical examiner trained in medicine, charged with investigating the cause of all unnatural deaths, including accidents, homicides, suicides, etc.
A post-mortem examination, ornecropsy, is far more common inveterinary medicine than inhuman medicine. For many species that exhibit few external symptoms (sheep), or that are not suited to detailed clinical examination (poultry, cage birds, zoo animals), it is a common method used byveterinary physicians to come to a diagnosis. A necropsy is mostly used like an autopsy to determine the cause of death. The entire body is examined at the gross visual level, and samples are collected for additional analyses.[40]
^The term necropsy usually refers to an autopsy for a non-human body, while the terms autopsy, post-mortem, and obduction are usually for human bodies.
^Hirst GM, Colson FH (1929). "Stories and Legends. A First Greek Reader, with Notes, Vocabulary and Exercises".The Classical Weekly.22 (12): 96.doi:10.2307/4389260.JSTOR4389260.
^Shojania KG, Burton EC, McDonald KM, Goldman L (2003). "Changes in rates of autopsy-detected diagnostic errors over time: a systematic review".JAMA: The Journal of the American Medical Association.289 (21):2849–56.doi:10.1001/jama.289.21.2849.PMID12783916.
^Roulson J, Benbow EW, Hasleton PS (December 2005). "Discrepancies between clinical and autopsy diagnosis and the value of post mortem histology; a meta-analysis and review".Histopathology.47 (6):551–559.doi:10.1111/j.1365-2559.2005.02243.x.PMID16324191.
^Wichmann D, Obbelode F, Vogel H, Hoepker WW, Nierhaus A, Braune S, Sauter G, Pueschel K, Kluge S (17 January 2012). "Virtual Autopsy as an Alternative to Traditional Medical Autopsy in the Intensive Care Unit: A Prospective Cohort Study".Annals of Internal Medicine.156 (2):123–130.doi:10.7326/0003-4819-156-2-201201170-00008.PMID22250143.
^Filograna L, Pugliese L, Muto M, Tatulli D, Guglielmi G, Thali MJ, Floris R (February 2019). "A Practical Guide to Virtual Autopsy: Why, When and How".Seminars in Ultrasound, CT and MRI.40 (1):56–66.doi:10.1053/j.sult.2018.10.011.PMID30686369.
^Pollock DA, O'Neil JM, Parrish RG, Combs DL, Annest JL (1993). "Temporal and geographic trends in the autopsy frequency of blunt and penetrating trauma deaths in the United States".JAMA: The Journal of the American Medical Association.269 (12):1525–31.doi:10.1001/jama.1993.03500120063027.PMID8445815.
Autopsy of a Murder – An interactive exploration of a murder scene and the science involved in a criminalistic investigation: autopsy and laboratory expertise. Produced by the Montreal Science Centre for its namesake exhibition.
