Post-mortem computed tomography improves completeness of the trauma registry: a single institution experience

Normal Distal Tibiofibular Syndesmosis Assessment Using Postmortem Computed Tomography (PMCT)

BACKGROUND

Distal tibiofibular syndesmotic injuries, often misdiagnosed, can lead to substantial morbidity. This study utilized postmortem computed tomography (PMCT) to define normal syndesmotic relationships in 131 subjects.

METHODS

Three parameters were measured: fibular rotation (FR), sagittal translation (ST), and incisura depth (ID).

RESULTS

Interobserver reliability was excellent for FR and ID but moderate for ST. Anatomical variability was wide, with FR ranging from -0.4° to 16.6°, ST from 0.33 mm to 3.49 mm, and ID from 1.89 mm to 6.05 mm. Side-to-side variability within subjects was minimal. Gender-specific differences were observed in ST, possibly due to size variations, highlighting the need for gender-specific diagnostic criteria.

CONCLUSIONS

Although establishing universal reference values is challenging, using contralateral ankles for comparison can enhance diagnostic accuracy in syndesmotic injuries. This study, the first of its kind, offers valuable insights into normal distal tibiofibular syndesmotic relationships based on PMCT data. Future validation studies in patients with syndesmotic injuries can further improve diagnostic accuracy.

Characterization of fatal blunt injuries using postmortem computed tomography

BACKGROUND

Rapid triage of blunt agonal trauma patients is necessary to maximize survival, but autopsy is uncommon, slow, and rarely informs resuscitation guidelines. Postmortem computed tomography (PMCT) can serve as an adjunct to autopsy in guiding blunt agonal trauma resuscitation.

METHODS

Retrospective cohort review of trauma decedents who died at or within 1 hour of arrival following blunt trauma and underwent noncontrasted PMCT. Primary outcome was the prevalence of mortal injury defined as potential exsanguination (e.g., cavitary injury, long bone and pelvic fractures), traumatic brain injury, and cervical spine injury. Secondary outcomes were potentially mortal injuries (e.g., pneumothorax) and misplacement airway devices. Patients were grouped by whether arrest occurred prehospital/in-hospital. Univariate analysis was used to identify differences in injury patterns including multiple-trauma injury patterns.

RESULTS

Over a 9-year period, 80 decedents were included. Average age was 48.9 ± 21.7 years, 68% male, and an average ISS of 42.3 ± 16.3. The most common mechanism was motor vehicle accidents (67.5%) followed by pedestrian struck (15%). Of all decedents, 62 (77.5%) had traumatic arrest prehospital while 18 (22.5%) arrived with pulse. Between groups there were no significant differences in demographics including ISS. The most common mortal injuries were traumatic brain injury (40%), long bone fractures (25%), moderate/large hemoperitoneum (22.5%), and cervical spine injury (25%). Secondary outcomes included moderate/large pneumothorax (18.8%) and esophageal intubation rate of 5%. There were no significant differences in mortal or potentially mortal injuries, and no differences in multiple-trauma injury patterns.

CONCLUSION

Fatal blunt injury patterns do not vary between prehospital and in-hospital arrest decedents. High rates of pneumothorax and endotracheal tube misplacement should prompt mandatory chest decompression and confirmation of tube placement in all blunt arrest patients.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

An unbroken ring of the chain of survival

This is a commentary on the study conducted by Kennedy et al. from Victoria, Australia, that analyzed the cohort of all adult EMS-witnessed out-of-hospital cardiac arrest (OHCA) patients in the region and compared patients treated during the COVID-19 period to a historical comparator period. The commentary summarizes the study findings and discusses the importance of the study in the context of the chain of survival and changes in airway management for OHCA patients during the COVID-19 pandemic.

Comparison of fatal traumatic medico-legal cases with postmortem computed tomography and autopsy: A pilot study in Taiwan

In order to determine the performance of postmortem computed tomography (PMCT) in identifying traumatic-relevant macroscopic findings in medico-legal cases, this retrospective observational pilot study involving nine trauma casualties who had received PMCT prior to autopsy. The comparison of these findings in six anatomical regions as dictated in Injury Severity Score (ISS) were performed. 104 traumatic-relevant findings were identified with achievement of 51% congruent findings. PMCT and autopsy had additionally found 22 and 29 findings respectively. PMCT had highest sensitivity for extremity injury (81.82%), followed by chest (73.91%), head, neck and face (71.43%), and abdomino-pelvic area (50%). It had excellent detection rate in abnormal air collection, fracture, foreign body localization, internal ballistic and intracranial pathology. However, the solid organ and vascular injuries as well as integumentary lesions were the major drawback. In conclusion, incorporation of PMCT to autopsy in medico-legal investigation helps to preserve the most abundant traumatic-relevant injuries compared to either modality.

Post-mortem computed tomography assessment of medical support device position following fatal trauma: a single-center experience

PURPOSE

To evaluate the percentage of misplaced medical support lines and tubes in deceased trauma patients using post-mortem computed tomography (PMCT).

METHODS

Over a 9-year period, trauma patients who died at or soon after arrival in the emergency department were candidates for inclusion. Whole body CT was performed without contrast with support medical devices left in place. Injury severity score (ISS) was calculated by the trauma registrar based on the injuries identified on PMCT. The location of support medical devices was documented in the finalized radiology reports.

RESULTS

A total of 87 decedents underwent PMCT, of which 69% (n = 60) were male. For ten decedents, the age was unknown. For the remaining 77 decedents, the average age was 48.4 years (range 18-96). The average ISS for the cohort was 43.4. Each decedent had an average of 3.3 support devices (2.9-3.6, 95% CI), of which an average of 1 (31.3%, 0.8-1.2, 95% CI) was malpositioned. A total of 60 (69.0%) had at least one malpositioned medical support device. The most commonly malpositioned devices were decompressive needle thoracostomies (n = 25/32, 78.1%). The least malpositioned devices were intraosseous catheters (n = 7/69, 10.1%). Nearly one quarter (n = 19/82, 23.2%) of mechanical airways were malpositioned, including 4.9% with esophageal intubation.

CONCLUSION

Malpositioned supportive medical devices are commonly identified on post-mortem computed tomography trauma decedents, seen in 69.0% of the cohort, including nearly one quarter with malpositioned mechanical airways. Post-mortem CT can serve as a useful adjunct in the quality improvement process by providing data for education of trauma and emergency physicians and first responders.

Post-Mortem CT Delivers Fast and Accurate Injury Identification in Trauma Patients

Background

Accurate and timely injury identification is critical but difficult to achieve in trauma patients who die shortly after arrival to the hospital. Autopsy has historically been used to detect injuries, but few undergo formal autopsy. This study investigates the utility of post-mortem computed tomography (PMCT) for injury identification in a diverse trauma population.

Methods

Cross-sectional study of adult trauma patients who died within 24 hours of arrival to a Level I trauma center were included. Among patients with PMCT, injury severity score (ISS) and number of injuries (NOI) were calculated either from physical exam alone (pre-PMCT) or exam and imaging (post-PMCT). ISS and NOI before and after PMCT were compared. A cause of death analysis was performed for patients who underwent comprehensive (ie, head, neck, and torso) PMCT. Non-parametric repeated measures tests were used, as appropriate.

Results

7.3% (N = 28) of patients received PMCT. Compared to pre-PMCT, median ISS (21 vs 3.5) and NOI (5 vs 2) were greater post-PMCT ( P < .001, respectively). Autopsy rate was 13.2% overall; 82.5% of autopsies were due to a penetrating mechanism, and median time to autopsy reporting was 38.5 days. Among 17 patients who received comprehensive PMCT, 64.7% had a single cause of death identified, and the remaining were classified as either multiple potential contributors or unknown.

Discussion

PMCT is a readily available method to identify injuries in trauma patients who expire shortly upon presentation. Given the low autopsy rate for blunt trauma and delay in reporting, PMCT is an important adjunct for trauma providers.

Sensitivity and specificity of post-mortem computed tomography in skull fracture detection-a systematic review and meta-analysis

Post-mortem computed tomography (PMCT) has been increasingly used as routine examination in forensic pathology. No recent review of the growing number of papers on the ability of PMCT to detect skull fracture exists, and original papers report sensitivities from 0.85 to 1.00. This systematic review (PROSPERO: CRD42021233264) aims to provide a meta-analysis of sensitivity and specificity of PMCT in skull fracture detection. We searched PubMed, MEDLINE and Embase for papers published between January 2000 and August 2021 reporting raw numbers, sensitivity and specificity or Abbreviated Injury Score for PMCT compared to autopsy. Papers without both PMCT and autopsy, no separate reporting of the neuro-cranium, exclusively on children, sharp trauma, gunshot or natural death as well as case reports and reviews were excluded. Two authors independently performed inclusion, bias assessment and data extraction. QUADAS-2 was used for bias assessment and a random effects models used for meta-analysis. From 4.284 hits, 18 studies were eligible and 13 included in the meta-analysis for a total of 1538 cases. All deceased were scanned on multi-slice scanners with comparable parameters. Images were evaluated by radiologists or pathologists. Intra- and inter-observer analyses were rarely reported. In summary, sensitivity of PMCT for detection of fractures in the skull base was 0.87 [0.80; 0.92] with specificity 0.96 [0.90; 0.98], and sensitivity for the vault was 0.89 [0.80; 0.94] with specificity 0.96 [0.91; 0.98]. The mixed samples are a limitation of the review.

CT imaging of extraglottic airway device-pictorial review

Compared to intubation with a cuffed endotracheal tube, extraglottic airway devices (EGDs), such as laryngeal mask airways, are considered less definitive ventilation conduit devices and are therefore often exchanged via endotracheal intubation (ETI) prior to obtaining CT images. With more widespread use and growing comfort among providers, reports have now described use of EGDs for up to 24 h including cases for which clinicians obtained CT scans with an EGD in situ. The term EGD encompasses a wide variety of devices with more complex structure and CT appearance compared to ETI. All EGDs are typically placed without direct visualization and require less training and time for insertion compared to ETI. While blind insertion generally results in functional positioning, numerous studies have reported misplacements of EGDs identified by CT in the emergency department or post-mortem. A CT-based classification system has recently been suggested to categorize these misplacements in six dimensions: depth, size, rotation, device kinking, mechanical blockage of the ventilation opening(s), and injury from EGD placement. Identifying the type of EGD and its correct placement is critically important both to provide prompt feedback to clinicians and prevent inappropriate medicolegal problems. In this review, we introduce the main types of EGDs, demonstrate their appearance on CT images, and describe examples of misplacements.

Extraglottic Airway Device Misplacement: A Novel Classification System and Findings in Postmortem Computed Tomography

STUDY OBJECTIVE

Extraglottic airway devices are frequently used during cardiac arrest resuscitations and for failed intubation attempts. Recent literature suggests that many extraglottic airway devices are misplaced. The aim of this study is to create a classification system for extraglottic airway device misplacement and describe its frequency in a cohort of decedents who died with an extraglottic airway device in situ.

METHODS

We assembled a cohort of all decedents who died with an extraglottic airway device in situ and underwent postmortem computed tomographic (CT) imaging at the state medical examiner's office during a 6-year period, using retrospective data. An expert panel developed a novel extraglottic airway device misplacement classification system. We then applied the schema in reviewing postmortem CT for extraglottic airway device position and potential complications.

RESULTS

We identified 341 eligible decedents. The median age was 47.0 years (interquartile range 32 to 59 years). Out-of-hospital personnel placed extraglottic airway devices in 265 patients (77.7%) who subsequently died out of hospital; the remainder died inhospital. The classification system consisted of 6 components: depth, size, rotation, device kinking, mechanical blockage of ventilation opening, and injury. Under the system, extraglottic airway devices were found to be misplaced in 49 cases (14.4%), including 5 (1.5%) that resulted in severe injuries.

CONCLUSION

We created a novel extraglottic airway device misplacement classification system. Misplacement occurred in greater than 14% of cases. Severe traumatic complications occurred rarely. Quality improvement activities should include review of extraglottic airway device placement when CT images are available and use the classification system to describe misplacements.

State of the art in post-mortem computed tomography: a review of current literature

Computed tomography (CT) and other advanced diagnostic imaging techniques are gaining popularity in forensic pathology. This paper aims to define and offer complete and easily accessible "state of the art" for post-mortem computed tomography (PMCT), by reviewing the latest international literature. The proposed format answers the "five Ws" that follows: (1) What: We report the different kinds of CT scan and settings generally used in post-mortem imaging. The machine most employed is a 8/16-slice spiral CT, usually without contrast enhancement. The introduction of some variables, such as CT-guided biopsies, post-mortem ventilation, and PMCT angiography is becoming increasingly useful. (2) Why: Literature highlights the many advantages of PMCT. Limitations can be partly overcome by modern imaging techniques and combined evaluation with traditional autopsy. (3) Who: Most authors agree that collaboration between different specialists, i.e., radiologists and pathologists, is the best scenario, since radiologic, anatomic, and forensic skills are needed simultaneously. The most important human factor is "teamwork". (4) When: Literature provides no absolute limits for performing PMCT. Some authors have tested PMCT as a replacement for conventional autopsy but found some limitations. Others evaluated PMCT as a guide or screening tool for traditional autopsy. (5) Where: Many research groups around the world have performed studies on the use of PMCT. Although few countries adopt PMCT in routine practice, its use is rapidly spreading.