The role of early postmortem CT in the evaluation of support-line misplacement in patients with severe trauma

Pre-hospital emergency medicine: a spectrum of imaging findings

The goal of emergency medical services (EMS) is to provide urgent medical care and stabilization prior to patient transport to a healthcare facility for definitive treatment. The number and variety of interventions performed in the field by EMS providers continues to grow as early management of severe injuries and critical illness in the pre-hospital setting has been shown to improve patient outcomes. The sequela of many field interventions, including those associated with airway management, emergent vascular access, cardiopulmonary resuscitation (CPR), patient immobilization, and hemorrhage control may be appreciated on emergency department admission imaging. Attention to these imaging findings is important for the emergency radiologist, who may be the first to identify a malpositioned device or an iatrogenic complication arising from pre-hospital treatment. Recognition of these findings may allow for earlier corrective action to be taken in the acute care setting. This review describes common EMS interventions and their imaging findings.

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.

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.

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.

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

PURPOSE

To describe our institutional experience with post-mortem computed tomography (PMCT) and its impact on decedent injury severity score (ISS) and to assess the adequacy of emergently placed support medical devices.

METHODS

Over a 5-year period, patients who died at or soon after arrival and have physical exam findings inconsistent with death were candidates for inclusion. Whole body CT was performed without contrast with support medical devices left in place. ISS was calculated with and without the PMCT findings. PMCT results were compared to autopsy findings, if performed. The location of support medical devices was documented.

RESULTS

A total of 38 decedents underwent PMCT, including 53.1% males and a mean age of 42.0 years. Pre-PMCT ISS based on physical exam findings alone was 5.2 (range 0-25), including 16 with ISS = 0. Post-PMCT ISS using the additional imaging data was 50.3 (range 21-75), including 15 with ISS = 50 or greater. Nearly half (47.4%) had at least one support medical device that was either malpositioned or suboptimally positioned, including 26.3% with malpositioned airway devices, 10.3% with malpositioned intra-osseous catheters, and 100% with malpositioned decompressive needle thoracotomies.

CONCLUSIONS

PMCT adds value in identifying injuries that otherwise may have gone undetected in lieu of a formal autopsy, thus creating a more complete trauma registry. The identification of malpositioned support lines and tubes allows for educational feedback to the first responders and trainees. Institutions with a low formal autopsy rate for trauma victims may benefit from developing a PMCT program.

Clinical consequences of chest tube malposition in trauma resuscitation: single-center experience

PURPOSE

Evaluation of trauma patients with chest tube malposition using initial emergency computed tomography (CT) and assessment of outcomes and the need for chest tube replacement.

METHODS

Patients with an injury severity score > 15, admitted directly from the scene, and requiring chest tube insertion prior to initial emergency CT were retrospectively reviewed. Injury severity, outcomes, and the positions of chest tubes were analyzed with respect to the need for replacement after CT.

RESULTS

One hundred seven chest tubes of 78 patients met the inclusion criteria. Chest tubes were in the pleural space in 58% of cases. Malposition included intrafissural positions (27%), intraparenchymal positions (11%) and extrapleural positions (4%). Injury severity and outcomes were comparable in patients with and without malposition. Replacement due to malfunction was required at similar rates when comparing intrapleural positions with both intrafissural or intraparenchymal positions (11 vs. 23%, p = 0.072). Chest tubes not reaching the target position (e.g., pneumothorax) required replacement more often than targeted tubes (75 vs. 45%, p = 0.027). Out-of-hospital insertions required higher replacement rates than resuscitation room insertions (29 vs. 10%, p = 0.016). Body mass index, chest wall thickness, injury severity, insertion side and intercostal space did not predict the need for replacement.

CONCLUSIONS

Patients with malposition of emergency chest tubes according to CT were not associated with worse outcomes compared to patients with correctly positioned tubes. Early emergency chest CT in the initial evaluation of severely injured patients allows precise detection of possible malposition of chest tubes that may require immediate intervention.

Mechanical complications and outcomes following invasive emergency procedures in severely injured trauma patients

This study aimes to determine the complication rates, possible risk factors and outcomes of emergency procedures performed during resuscitation of severely injured patients. The medical records of patients with an injury severity score (ISS) >15 admitted to the University Hospital Leipzig from 2010 to 2015 were reviewed. Within the first 24 hours of treatment, 526 patients had an overall mechanical complication rate of 26.2%. Multivariate analysis revealed out-of-hospital airway management (OR 3.140; 95% CI 1.963–5.023; p < 0.001) and ISS (per ISS point: OR 1.024; 95% CI 1.003–1.045; p = 0.027) as independent predictors of any mechanical complications. Airway management complications (13.2%) and central venous catheter complications (11.4%) were associated with ISS >32.5 (p < 0.001) and ISS >33.5 (p = 0.005), respectively. Chest tube complications (15.8%) were associated with out-of-hospital insertion (p = 0.002) and out-of-hospital tracheal intubation (p = 0.033). Arterial line complications (9.4%) were associated with admission serum lactate >4.95 mmol/L (p = 0.001) and base excess <−4.05 mmol/L (p = 0.008). In multivariate analysis, complications were associated with an increased length of stay in the intensive care unit (p = 0.019) but not with 24 hour mortality (p = 0.930). Increasing injury severity may contribute to higher complexity of the individual emergency treatment and is thus associated with higher mechanical complication rates providing potential for further harm.