A medic unit responded to a “stab wound to the chest” in an apartment. On arrival, law enforcement reported that the scene had been secured and that a patient was located in a bedroom. EMS providers found a 47-year-old male patient lying supine in bed with a kitchen steak knife impaled in the left side of his chest.
Assessment & Treatment
The patient stated that he’d stabbed himself in the chest because he was despondent over a recent breakup. He smelled of alcohol but could speak in full sentences. His breath sounds were equal bilaterally, his respiratory rate was 18 breaths per minute, and his pulse oximetry showed an SpO2 of 94%.
These findings demonstrated that his airway was intact and his respiratory status hadn’t been compromised. The knife was impaled in his left chest in the third intercostal space at the mid-clavicular line. It appeared stable due to the depth of impalement. There was no active bleeding from the wound. His pulse was 58 beats per minute, and his blood pressure was 104/64 mmHg. Although he appeared intoxicated, his Glasgow Coma Scale score was 15.
A rapid scan of his body revealed no other injuries. After carefully stabilizing the knife in place with a gauze roll and tape and placing the patient on oxygen at 4 LPM by nasal cannula, his SpO2 increased to 99%. He was gently slid onto the stretcher and moved to the ambulance.
Once in the unit, the patient was placed on an ECG, and transport was initiated. The total scene time was eight minutes. En route to the trauma center, two 16 gauge IV lines were started at a KVO rate. Reassessment of his breath sounds and vital signs revealed no significant changes during transport.
Trauma Center Care
Once in the trauma center, the trauma team repeated the primary survey and measured vital signs (respiratory rate=16; pulse=58; blood pressure=106/68), and performed a focused assessment with sonography for trauma exam, a physician-performed, rapid diagnostic study, easily performed at the patient’s bedside. It uses ultrasound to identify fluid (blood) in the pericardial sac, pleural cavities and peritoneal cavity. The patient was emergently transferred to the operating room, where an exploratory thoracotomy was performed.
It was determined that the knife had penetrated through the pericardium and into the left ventricle of the heart. About 70 mL of blood was found in the pericardial cavity. The heart was repaired, and the chest was closed. His post-operative course was uneventful, so he was transferred to an inpatient psychiatry unit for treatment for depression one week following the injury.
In the prehospital setting, the key principle for managing an impaled object is not to remove it, but rather to stabilize it, if necessary. The rationale behind this approach is that the object could have damaged major blood vessels, which are tamponaded by the object. If it’s removed, the pressure is released, and life-threatening, potentially uncontrollable hemorrhage could result.
In fact, impaled objects are almost never removed in the emergency department, but rather patients are taken to the operating room. There, it’s removed in a controlled environment where an operation can be performed to control ensuing hemorrhage.
Patients with impaled-object injuries may be categorized into two groups: simple impalements by such objects as knives or arrows, and complex impalements, in which the patient is pinned or trapped by the impaling object. Simple impalements tend to be much easier to manage, because the objects generally don’t interfere with patient assessment, packaging and transport. On rare occasions, however, the object may need to be shortened so the patient can fit in an ambulance.
Examples of complex impalements include those with a body part impaled on a fence or an object that comes through the windshield of the car and pierces the torso. These impalements require some degree of extrication to free the patient for transport. This typically involves sawing the object, an action that may result in significant pain to the patient from vibration or movement of the object. In very rare circumstances, in which dividing the object may pose a significant challenge, providers may decide to remove the patient from the object and attempt to control any hemorrhage. Such a decision is best made by a physician brought to the scene.
When an object is impaled in an extremity, it may be prudent to apply a tourniquet proximal to the wound (i.e., between the torso and the wound).
In this case, the tip of the knife resulted in a full-thickness puncture to the left ventricle of the heart, but the knife had withdrawn from the heart and was lying adjacent to it.
Bleeding from the heart resulted in a hemopericardium (blood in the pericardial sac), but not a cardiac tamponade. A cardiac tamponade occurs when an injury to the heart causes blood to exit the heart with each contraction and fills the pericardium to the point that it interferes with normal filling of the heart chambers.
Based on Starling’s law of the heart, when the heart fails to fill sufficiently, its ability to pump is impaired. This results in shock. If untreated, it may lead to death. With this patient, a clot had formed in the wound before enough blood in the pericardium led to compromised heart functioning.
Impaled objects can present EMS providers with significant challenges for management, especially if the patient is entrapped or pinned by the impalement. In such cases, good communication and teamwork between rescuers and providers are important. However, in certain circumstances, impaled objects shouldn’t be removed in the prehospital setting. Some impalements are potentially life threatening, so patients with impaled objects should be rapidly assessed, packaged and transported to a facility with the capability of performing immediate surgical intervention. JEMS
This article originally appeared in June 2011 JEMS as “More than Skin Deep: Use caution when treating impalement injuries.”