Blunt Cardiac Rupture with Prehospital Pulseless Electrical Activity: A Rare Successful Experience

A 6-year case series of resuscitative thoracotomies performed by a helicopter emergency medical service in a mixed urban and rural area with a comparison of blunt versus penetrating trauma

Background

Resuscitative thoracotomy (RT) is an intervention that can be performed in the prehospital setting for relieving cardiac tamponade and/or obtaining vascular control of suspected sub-diaphragmatic haemorrhage in patients in traumatic cardiac arrest. The aim of this retrospective case study is to compare the rates of return of spontaneous circulation (ROSC) in RTs performed for both penetrating and blunt trauma over 6 years in a mixed urban and rural environment.

Methods

The electronic records of a single helicopter emergency medical service were reviewed between 1st June 2015 and 31st May 2021 for RTs. Anonymised data including demographics were extracted for relevant cases. Data were analysed with independent t-tests and Χ² tests. A p value < 0.05 was considered statistically significant.

Results

Forty-four RTs were preformed within the 6 years (26 for blunt trauma). Eleven ROSCs were achieved (nine blunt, two penetrating) but no patient survived to discharge. In contrast to RTs for penetrating trauma, twelve of the RTs for blunt trauma had a cardiac output present on arrival of the prehospital team (p = 0.01). Two patients had an RT performed in a helicopter (one ROSC) and two on a helipad (both achieving ROSC), likely due to the longer transfer times seen in a more rural setting. Four of the RTs for blunt trauma (15%) were found to have a cardiac tamponade versus seven (39%) of the penetrating trauma RTs.

Conclusion

Prehospital RT remains a procedure with low rates of survival but may facilitate a ROSC to allow patients to reach hospital and surgery, particularly when distances to hospitals are greater. A higher-than-expected rate of cardiac tamponade was seen in RTs for blunt trauma, although not caused by a right ventricular wound but instead due to underlying vessel damage.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-022-00997-4.

Prehospital ultrasound in emergency medicine: incidence, feasibility, indications and diagnoses

BACKGROUND

Sonography is an established diagnostic procedure in hospitals, but is not routinely used in prehospital emergency medicine. Several studies have addressed the use of ultrasound during helicopter flights and in emergency rooms, few in prehospital settings, but most focused on abdominal blunt trauma. Several case reports describe crucial decisions distinguished by ultrasound.

METHODS

In this study, four different handheld ultrasound systems in 4 helicopters and one emergency vehicle were used over a cumulative period of 3 years. Incidence, feasibility, indication, diagnoses and exploration time (in subgroups) were investigated in an overall profile of emergency patients, encompassing the area of internal medicine.

RESULTS

On 971 missions ultrasound systems were available. In 17% of the cases ultrasound was considered valuable, in 144 patients (14.8%) sonographic studies were performed. Additional information could be given in 130 cases (90%). Compared with the available clinical data (return rate of 76%) there were no false-positive findings during this study, resulting in a specificity and positive predictive value of 100%, showing this technique to be reliable. Sensitivity was 85%, accuracy was 96% and negative predictive value was 95%.

CONCLUSION

Ultrasound is the only imaging modality and a useful diagnostic tool in prehospital emergency medicine. Helpful information can be provided in at least one of six cases (or even more) in a trauma-dominated collective. Examination time is short; it will not significantly delay medical care. Ultrasound examination could improve triage in cases of more than one patient in disaster medicine, but further studies are necessary.

Cardiac rupture following blunt trauma

Cardiac rupture is the most extreme manifestation of blunt cardiac injury. In the first half of the 20th century this lesion was uniformly fatal. Since the first successful post-traumatic cardiorrhaphy by Desforges in 1955, multiple case reports and retrospective reviews have documented successful operative repair and survival of patients with this injury. Despite these successes, blunt cardiac rupture remains associated with a high mortality rate. The rarity of this condition and the heterogeneity of the literature make determination of exact epidemiologic data difficult. The classic clinical presentation is not universal and a subset of patients may present asymptomatically. Rapid transportation to medical care, accurate timely diagnosis and emergent operative intervention are essential for successful outcome. The use of ultrasonography in the trauma bay is a key component of early identification of these injuries. Specific outcome factors associated with survival are difficult to determine and even in those who survive to medical attention mortality rates remain as high as 60—90%.

Prehospital ultrasound by paramedics: results of field trial

OBJECTIVES

The objective was to determine if 9-1-1 paramedics trained in ultrasound (US) could adequately perform and interpret the Focused Assessment Sonography in Trauma (FAST) and the abdominal aortic (AA) exams in the prehospital care environment.

METHODS

Paramedics at two emergency medical services (EMS) agencies received a 6-hour training program in US with ongoing refresher education. Paramedics collected US in the field using a prospective convenience methodology. All US were performed in the ambulance without scene delay. US exams were reviewed in a blinded fashion by an emergency sonographer physician overreader (PO).

RESULTS

A total of 104 patients had an US performed between January 1, 2008, and January 1, 2009. Twenty AA exams were performed and all were interpreted as negative by the paramedics and the PO. Paramedics were unable to obtain adequate images in 7.7% (8/104) of the patients. Eighty-four patients had the FAST exam performed. Six exams (6/84, 7.1%) were read as positive for free intraperitoneal/pericardial fluid by both the paramedics and the PO. FAST and AA US exam interpretation by the paramedics had a 100% proportion of agreement with the PO.

CONCLUSIONS

This pilot study shows that with close supervision, paramedics can adequately obtain and interpret prehospital FAST and AA US images under protocol. These results support a growing body of literature that indicates US may be feasible and useful in the prehospital setting.

Blunt traumatic cardiac rupture: therapeutic options and outcomes

INTRODUCTION

Cardiac rupture following blunt thoracic trauma is rarely encountered by clinicians, since it commonly causes death at the scene. With advances in traumatology, blunt cardiac rupture had been increasingly disclosed in various ways. This study reviews our experience of patients with suspected blunt traumatic cardiac rupture and proposes treatment protocols for the same.

METHODS

This is a 5-year retrospective study of trauma patients confirmed with blunt traumatic cardiac rupture admitted to a university-affiliated tertiary trauma referral centre. The following information was collected from the patients: age, sex, mechanism of injury, initial effective diagnostic tool used for diagnosing blunt cardiac rupture, location and size of the cardiac injury, associated injury and injury severity score (ISS), reversed trauma score (RTS), survival probability of trauma and injury severity scoring (TRISS), vital signs and biochemical lab data on arrival at the trauma centre, time elapsed from injury to diagnosis and surgery, surgical details, hospital course and final outcome.

RESULTS

The study comprised 8 men and 3 women with a median age of 39 years (range: 24-73 years) and the median follow-up was 5.5 months (range: 1-35 months). The ISS, RTS, and TRISS scores of the patients were 32.18+/-5.7 (range: 25-43), 6.267+/-1.684 (range: 2.628-7.841), and 72.4+/-25.6% (range: 28.6-95.5%), respectively. Cardiac injuries were first detected using focused assessment with sonography for trauma (FAST) in 4 (36.3%) patients, using transthoracic echocardiography in 3 (27.3%) patients, chest CT in 1 (9%) patient, and intra-operatively in 3 (27.3%) patients. The sites of cardiac injury comprised the superior vena cava/right atrium junction (n=4), right atrial auricle (n=1), right ventricle (n=4), left ventricular contusion (n=1), and diffuse endomyocardial dissection over the right and left ventricles (n=1). Notably, 2 had pericardial lacerations presenting as a massive haemothorax, which initially masked the cardiac rupture. The in-hospital mortality was 27.3% (3/11) with 1 intra-operative death, 1 multiple organ failure, and 1 death while waiting for cardiac transplantation. Another patient with morbid neurological defects died on the thirty-third postoperative day; the overall survival was 63.6% (7/11). Compared with the surviving patients, the fatalities had higher RTS and TRISS scores, serum creatinine levels, had received greater blood transfusions, and had a worse preoperative conscious state.

CONCLUSIONS

We proposed a protocol combining various diagnostic tools, including FAST, CT, transthoracic echocardiography, and TEE, to manage suspected blunt traumatic cardiac rupture. Pericardial defects can mask the cardiac lesion and complicate definite cardiac repair. Comorbid trauma, particularly neurological injury, may have an impact on the survival of such patients, despite timely repair of the cardiac lesions.

[Cardiac arrest following blunt chest injury. Emergency thoracotomy without ifs or buts?]

In German-speaking countries, most serious thoracic injuries are attributable to the impact of blunt force; they are the second most frequent result of injury after head injury in polytrauma patients with multiple injuries. Almost one in every three polytraumatized patients with significant chest injury develops acute lung failure, and one in every four, acute circulatory failure. The acute circulatory arrest following serious chest injury involves a high mortality rate, and in most cases it reflects a tension pneumothorax, cardiac tamponade, or hemorrhagic shock resulting from injury to the heart or one of the large vessels close to it. Brisk drainage of tension pneumothorax and adequate volume restoration are therefore particularly important in resuscitation of multiply traumatized patients, as are rapid resuscitative thoracotomy to allow direct heart massage, drainage of pericardial tamponade, and control of hemorrhage. However the probability of survival described in the literature is very low for patients sustaining severe chest trauma with acute cardiac arrest. The case report presented here describes a female polytrauma patient who suffered an acute cardiac arrest following cardiac tamponade after admission in the emergency department and who survived without neurological deficits after an emergency thoracotomy. Selections from the topical literature can help the treating physician in the emergency department in making decisions on whether an emergency thoracotomy is indicated after a blunt chest injury and on the procedure itself.