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Certificates of medical evidence are often used to aid the court in assessing the cause and severity of a victim’s injuries. In cases with significant blood loss, the question whether the bleeding itself was life-threatening sometimes arises. To answer this, the volume classification of hypovolemic shock described in ATLS^® is commonly used as an aid, where a relative blood loss > 30% is considered life-threatening. In a recent study of deaths due to internal haemorrhage, many cases had a relative blood loss < 30%. However, many included cases had injuries which could presumably cause deaths via other mechanisms, making the interpretation uncertain. To resolve remaining ambiguity, we studied whether deaths due to isolated liver lacerations had a relative blood loss < 30%, a cause of death where the mechanism of death is presumably exsanguination only. Using the National Board of Forensic Medicine autopsy database, we identified all adult decedents, who had undergone a medico-legal autopsy 2001–2021 (n = 105 952), where liver laceration was registered as the underlying cause of death (n = 102). Cases where death resulted from a combination of also other injuries (n = 79), and cases that had received hospital care, were excluded (n = 4), leaving 19 cases. The proportion of internal haemorrhage to calculated total blood volume in these fatal pure exsanguinations ranged from 12 to 52%, with 63% of cases having a proportion < 30%. Our results lend further support to the claim that the volume classification of hypovolemic shock described in ATLS^® is inappropriate for assessing the degree of life-threatening haemorrhage in medico-legal cases.

A key element for diagnosing cardiac enlargement in an autopsy setting is relevant heart weight references. However, most available references are to a large extent not representative of a medicolegal autopsy population, implying that reference weights are likely lower than those in the relevant population.To establish more applicable heart weight references in a medicolegal autopsy population, we designed a heart weight model that accounts for undiagnosed cardiac enlargement using data from 11,897 nontraumatic Swedish medicolegal autopsy cases autopsied between 2010 and 2019. The model was validated in 296 nonobese young adult suicidal hanging cases.For a decedent of average height (174 cm), the evidence that a heart weight was enlarged reached weak support at approximately 430 g, substantial support at approximately 480 g, and strong support at 520 g. The modeled prevalence of cardiac enlargement was very high among elderly and obese decedents.We believe that our model is more applicable in a medicolegal setting than those previously published. The presented quantification of the degree of uncertainty regarding diagnosis can help the pathologist in diagnosing cardiac enlargement. To facilitate the use of this model, we also made it available through a simple online tool (https://formedum.shinyapps.io/HeartWeightCalc/).

Fatal intoxications with opioids are known to be associated with an increased lung weight, as well as with brain and pulmonary edema and urinary retention. However, there is evidence to suggest that fatal intoxications with non-opioid substances are also associated with increased lung weight; however, the latter aspect has not been comprehensively analyzed. To determine to what extent opioid and non-opioid substances are associated with increased lung and brain weight, we studied these organs in cases where the cause of death was attributed to intoxication with a single agent. Using data from cases autopsied at the National Board of Forensic Medicine (NBFM) in Sweden from 2009 through 2019 where the cause of death was attributed to a single substance, we created models of combined lung weight and brain weight. The models used age and sex as predictors as well as nested varying effects for the specific intoxicant and category of intoxicant. Suicidal hanging with negative toxicology cases served as controls. The population majority was male among both intoxications (68%) and controls (83%). The most common single substance group was opioids. All tested substances were associated with heavier lungs than controls, with the largest effect in the opioid group. Our findings show that several substances are associated with increased lung weight and that among intoxication deaths there is no difference in expected brain weight between substances. Hence, heavy lungs, without a reasonable explanation, should prompt a broad toxicological screening.

The goal of a medico-legal autopsy is primarily to determine the cause and manner of death. To this end, the pathologist often uses auxiliary analyses, including histology. However, the utility of routine histology in all medico-legal autopsies is unknown. Earlier studies on the utility of routine histology have shown inconsistent effects, with some studies recommending it and others rejecting it. To study the degree to which histology informs on the underlying cause of death, we sent autopsy reports from suspension-, immersion-, fire-, and traffic-related deaths to senior board-certified forensic pathologists and had them assess the cause of death, first without knowledge of the histological findings and then with knowledge thereof. Fifty cases were identified in each of four subgroups: fire-, immersion-, suspension-, and traffic-related deaths. The autopsy reports were anonymized, and the histological findings and conclusions were removed. Two board-certified forensic pathologists independently reviewed the reports in each subgroup and assessed the manner and underlying cause of death (including their certainty of this assessment on a five-level scale) with and without access to histological findings. The probability of changing the underlying cause of death posthistology was low in all study groups. There was a slight increase in the degree of certainty posthistology in cases where the underlying cause of death was not changed, but only when the antehistology certainty was low. Our results suggest that histology does not meaningfully inform on the underlying cause of death in suspension-, immersion-, fire-, and traffic-related deaths except when antehistology certainty is low.

The main purpose of a medico-legal autopsy is to determine the cause and manner of death. A forensic pathologist makes assessments of this using several sources of information, one of which is the discrepancy between measured organ weight and reference values. Of particular interest is the heart weight in heart disease and the weight of the lungs in fatal intoxications. 

In this thesis, a linear model of lung weight was created, but the model could at best explain only 13% of the variation in combined lung weight (Paper I). Unsurprisingly, this meant that the model was a poor definition of “normal” lung weight and could not be used to identify intoxication cases (Paper II). A ratio of lung weight to heart weight (LWHW ratio) also failed to differentiate intoxication cases from controls. The poor performance of these methods could plausibly have been due to fatal intoxications with only some substances being associated with increased lung weight, but an analysis showed that many common intoxicants were associated with heavier lungs than hanging deaths (Paper III). 

To establish heart weight references more applicable in a medico-legal autopsy population, a model of heart weight accounting for undiagnosed cardiac hypertrophy was created (Paper IV). The model showed that for a decedent of average the evidence that a was hypertrophic reached, substantial support at around 470 g.

In conclusion, a definition of “heavy lungs” remains elusive. However, it seems to be a finding compatible with fatal intoxications with many substances and the low predictive value found may be due to study design. The heart weight model presented allows pathologists to assess the evidence of cardiac hypertrophy more easily than previously published models.

Background: The northern regions of the Nordic countries have common challenges of sparsely populated areas, long distances, and an arctic climate. The aim of this study was to compare the cause and rate of fatal injuries in the northernmost area of the Nordic countries over a 5-year period.

Methods: In this retrospective cohort, we used the Cause of Death Registries to collate all deaths from 2007 to 2011 due to an external cause of death. The study area was the three northernmost counties in Norway, the four northernmost counties in Finland and Sweden, and the whole of Iceland.

Results: A total of 4308 deaths were included in the analysis. Low energy trauma comprised 24% of deaths and high energy trauma 76% of deaths. Northern Finland had the highest incidence of both high and low energy trauma deaths. Iceland had the lowest incidence of high and low energy trauma deaths. Iceland had the lowest prehospital share of deaths (74%) and the lowest incidence of injuries leading to death in a rural location. The incidence rates for high energy trauma death were 36.1/100000/year in Northern Finland, 15.6/100000/year in Iceland, 27.0/100000/year in Northern Norway, and 23.0/100000/year in Northern Sweden.

Conclusion: We found unexpected differences in the epidemiology of trauma death between the countries. The differences suggest that a comparison of the trauma care systems and preventive strategies in the four countries is required.

Fatal intoxications are common in a medico-legal autopsy setting and are associated with sparse findings during autopsy. It has been suggested that an increased lung weight may be associated with such fatalities. Previous literature is generally limited to a descriptive approach, including only opioid deaths, and lacking a definition of “heavy” lungs. Our aim was to create a model to identify cases with heavy lungs and to assess the predictive power of “heavy” lungs in identifying cases of different types of fatal intoxications during autopsy in an unselected medico-legal autopsy population. We identified all medico-legal autopsy cases ≥18 years in Sweden from 2000 through 2013. The lung weight to heart weight (LWHW) ratio was calculated. The positive predictive values (PPV) and negative predictive values (NPV) of both lung weight and LWHW ratio were calculated. Mean lung weight was higher in the intoxication group but the predictive power in the individual case was limited. Lung weight to heart weight ratio had better predictive power than lung weight alone, with a PPV of at most 0.15(0.14, 0.16 95% CI), while the NPV was 0.96 (0.95, 0.96 95% CI). The association between fatal intoxication and increased lung weight was positive, regardless of method and cutoffs used. While the PPV was poor, the NPV could reduce suspicion of fatal intoxication in the absence of other information. LHWH ratio is only a probability factor for fatal intoxication; accurate cause of death determination—as always—requires consideration of circumstances, autopsy, and toxicologic findings.

Background Postmortem imaging has been used for more than a century as a complement to medico-legal autopsies. The technique has also emerged as a possible alternative to compensate for the continuous decline in the number of clinical autopsies. To evaluate the diagnostic accuracy of postmortem imaging for various types of findings, we performed this systematic literature review. Data sources The literature search was performed in the databases PubMed, Embase and Cochrane Library through January 7, 2015. Relevant publications were assessed for risk of bias using the QUADAS tool and were classified as low, moderate or high risk of bias according to pre-defined criteria. Autopsy and/or histopathology were used as reference standard. Findings The search generated 2600 abstracts, of which 340 were assessed as possibly relevant and read in full-text. After further evaluation 71 studies were finally included, of which 49 were assessed as having high risk of bias and 22 as moderate risk of bias. Due to considerable heterogeneity - in populations, techniques, analyses and reporting - of included studies it was impossible to combine data to get a summary estimate of the diagnostic accuracy of the various findings. Individual studies indicate, however, that imaging techniques might be useful for determining organ weights, and that the techniques seem superior to autopsy for detecting gas Conclusions and Implications In general, based on the current scientific literature, it was not possible to determine the diagnostic accuracy of postmortem imaging and its usefulness in conjunction with, or as an alternative to autopsy. To correctly determine the usefulness of postmortem imaging, future studies need improved planning, improved methodological quality and larger materials, preferentially obtained from multi-center studies.

Heavy combined lung weight at autopsy is a non-specific autopsy finding associated with certain causes of death such as intoxication. There is however no clear definition of what constitutes "heavy" lung weight. Different reference values have been suggested but previous studies have been limited by small select populations and only univariate regression has been attempted. The aim of this study was to create a model to estimate lung weight from decedent parameters. We identified all cases >18 years age autopsied at the Swedish National Board of Forensic Medicine from 2000 through 2013, excluding cases with a post-mortem interval >5 days as well as cases with extreme values, totalling 24,056 cases. We analysed body weight, body height, sex, age, BMI, BSA as well as untransformed and transformed lung weight. The analysis was stratified for sex. We evaluated the fit of the models and that the model assumptions were not violated. We set out to apply the model with the highest residual sum of squares to derive limits for heavy lungs. In univariate regression BSA and height showed best performance. The final model included height, weight and age group. After excluding large standardized residuals (>3, <-3) the final model achieved R-2 of 0.132 and 0.106 for women and men respectively. While we managed to create a multivariate model its performance was poor, possibly a fact reflective of the physiological nature of the lungs and in turn its variability in fluid content. Linear regression is a poor model for estimating lung weight in an unselected population.