Throughout its long history, post-mortem examination has remained the gold standard against which any ante-mortem clinical diagnosis is compared. [4] It continues to play a central role in the forensic analysis of unnatural death as well as representing an important tool for medical audit, underpinning the clinical governance of hospital services. Autopsies also provide opportunities for the teaching of medical, nursing and allied health professionals, and continues to contribute towards research and the understanding of disease, as demonstrated most dramatically in the evaluations of recent deaths due to Covid-19 as caused by the novel coronavirus SARS-CoV-2. [5] In certain cases, it also provides additional diagnoses, as per our data, class I-IV contributed information in 42 cases (42.4%) which was unknown prior to the post-mortem results.
The focus of this study was to ascertain the number of autopsies undertaken on patients dying in our paediatric intensive care unit, and to establish the contribution the autopsy made to the understanding of the patient’s illness. The autopsy rate during the period of the study was 25% which is lower than that previously reported in the US at 36%. [6] Autopsy rates have fallen in many parts of the world, with a relatively precipitous fall in consented autopsies in Ireland following public disquiet due to revelations of organ retention in 1999. Adappa et al reported lack of consent as the primary reason for the reduction in autopsy rates from the period 1994–1996 compared to 2001–2003. [7] In our institution, the autopsy rate fell by 40% in the period 2000–2002 in part due to reluctance of families to give consent, and also in part by medical staff’s reluctance to discuss the prospect with families given the public discussion at the time. The autopsy rate in our unit remained relatively stable throughout the study period, however the majority of these were performed under the direction of the coroner. Seventy-five cases (75%) involved in our study underwent post-mortem after discussion with the coroner.
Whether legally directed or consented by families, it is important that autopsy rates remain at a sufficient level to permit detection of systemic errors in the performance of an institution. It is therefore vital that hospital staff continue to advocate for a high level of post mortem interrogation of deaths, so that they may be able to reassure the hospital authorities and users of the service that their service continues to provide an appropriate level of care.
To support physicians in pursuing this goal, it is important to acknowledge the limitations of clinical diagnosis. Although we applied an “error” classification tool to describe discrepancies between clinically derived diagnostic conclusions and autopsy findings, this should not be taken to mean that shortcomings in the care delivered have been identified. Rather, such new findings, merely serve to highlight the unique role this potent form of investigation plays in furthering our understanding of disease. Previous studies have shown that autopsies add new information in 23-47.5% of cases and previously reported major discrepancy rates amongst the paediatric age group have varied but remain approximately 20%. [8–10] Our review identifies a major discrepancy in 14.1% of examinations, a figure derived from the combination of Class 1 and Class 2 errors. In part, this comparatively low figure may reflect the relatively high percentage of patients with congenital heart disease in which either detailed imaging or surgical intervention had been performed prior to the death. It may also reflect improvements in the quality of imaging and other diagnostic modalities which underlie secular decreasing discrepancy rates as published, in relation to both paediatric and adult ICU cohorts. [11–13]
However, even with these improvements and although many authors have discussed alternatives, we find it difficult to envisage a scenario in which it would be possible to entirely remove the need for post-mortem examinations for the foreseeable future. A dry chart review following the death of a patient can often help opinions coalesce around a likely cause of death. Post-mortem cross sectional imaging with CT or MR can also provide critical information about the cause of death. Nonetheless, concordance rates with CT scanning are at best moderate (57.1–83.3%). [14–17] In circumstances where imaging is helpful, it is often best used as a means of focusing subsequent invasive post-mortem examination which might potentially be limited to a biopsy of a region of interest rather than full body examination.
While not detracting from the principal finding that discrepancies remain a feature of post mortem examinations, it is appropriate to acknowledge some subjectivity in the application of the Goldman Error Classification system. The authors of this study had some lengthy conversations about many of the individual patients whose clinical care and autopsy findings were reviewed. Indeed, one of the conclusions of the study is the difficulty in applying a relatively rigid Goldman classification of errors to the complex setting of an intensive care unit in which patients frequently have multiple co-morbidities. Instead of identifying single discrepancies that were easily designated as one class or another, the conversations often revolved around the re-evaluation of the relative contribution of the multiple problems already known to afflict an individual patient. Thus, for example, a patient with known congenital heart disease, lung disease associated with prematurity and superimposed sepsis might, after a discussion of the clinical data and post-mortem findings, have a re-interpretation of the relative contributions each of these known findings made to the patient’s ultimate demise. As such, even when not detecting a discrepancy per se, the autopsy process contributed to a change in the narrative given to the family by the hospital staff.
The role autopsy plays in arriving at the most in-depth understanding of the factors contributing to death is central to the way post-mortem investigations are communicated in our institution. To facilitate this, where indicated, the pathologist meets with the family close to the time of death to discuss conducting a post mortem examination. This helps to facilitate questions the family may have regarding the procedure and ensures clarity about the post mortem process. This open discourse ensures clarity and consistency of information is imparted to the patient’s family. [18] Each death in our Unit is discussed at a multidisciplinary morbidity and mortality meeting where all teams involved in the patients’ care can attend. Post-mortem reports are presented at this multidisciplinary mortality review meeting. Care is discussed and evaluated and an agreed narrative conclusion reached. This considered opinion is then delivered to parents in face-to-face at follow-up, next-of-kin clinics. These afford parents an opportunity to ask questions about the findings and any aspects of care. [19] This integration of post-mortem results into Unit Morbidity and Mortality case discussion, as well as bereavement follow-up with the family, places the autopsy within a continuum of care offered to the patient and their family, rather than as a discrete exercise undertaken by a detached pathologist, and divorced from the patient and staff caring for them.
Our study had a number of limitations. It was retrospective, and although this was largely immaterial in relation to the post mortem finding, collection and evaluation of such clinical data as is pertinent, would be more easily and more comprehensively performed in a prospective fashion. The majority of post mortem exams reviewed were performed at the direction of the Coroner’s office. This may limit the generalisability of our findings to exams performed on medical rather than legal grounds. Also assignment of Goldman classification was not blinded or undertaken by medical professionals unaffiliated with our centre. We do not believe these limitations detract from the central findings in this study.