When a patient is started on anticoagulant therapy, the purpose is to prevent clot formation or propagation. Anticoagulants can improve morbidity and mortality by maintaining cardiac stent patency, reducing the propagation of pulmonary emboli, or preventing formation of intra-cardiac thrombi.1,2 Unfortunately even after minor trauma, these medications can cause major problems. When a patient on clopidogrel is in a motor vehicle collision (MVC) or an elderly patient on warfarin falls out of their bed, the once life-improving therapy becomes potentially life-threatening. It is important for emergency care providers to maintain a high index of suspicion for life-threatening bleeds in all patients on anticoagulation following even minor injuries. The purpose of this discussion is to look beyond the intracranial hemorrhages (ICH) and to consider 5 other sources of bleeding that can occur in anticoagulated patients.
One of the first questions we pose to any elderly patient who presents after a fall is whether they take any blood thinners. This is because of the incredibly high rate of ICH that occurs with warfarin (5.1%) and clopidogrel (12%) after even minor blunt head injury.3 ACEP guidelines recommend considering a noncontrast CT scan of the head on all anticoagulated patients with head trauma.4 However, there are many other places where bleeding can occur depending on the mechanism of injury and location of impact. Bleeding from some sites can be subtler and harder to diagnose.
An 89 year-old woman with a history of atrial fibrillation on warfarin presents to the Emergency Department 4 hours after a mechanical fall from standing. She arrives tachycardic to 120 bpm with a blood pressure of 98/55. She complains of left sided pelvic pain. Her physical exam demonstrates that she is in atrial fibrillation. She is mentating well, in no obvious distress, and has mild pain on palpation of the left pelvis. She does not have any pain with left lower extremity log rolling, axial loading, or range of motion of the hip.
Her tachycardia is attributed to her known paroxysmal atrial fibrillation. The physician performs a FAST exam which is negative, and orders X-rays of the left hip and pelvis which are also negative.
Soon after she returns from the X-ray, her systolic blood pressure drops to the 60s and her mental status is altered. An immediate CT chest/abdomen/pelvis is performed, and she is transfused 2 units of O-negative blood. The CT scan reveals a pelvic hematoma and she is taken for embolization with vascular interventional radiology (VIR).
This case illustrates why it is important to consider an internal source of bleeding in low mechanism trauma in patients on anticoagulation even with a normal exam, FAST, chest X-ray, and pelvic X-ray especially in the setting of vital sign abnormalities.
Older adults are more likely than younger adults to develop bleeds in anatomic locations that are not easily assessed by physical exam or a FAST, and so could be missed. In a retrospective study of severely injured trauma patients (Injury Severity Score > 16) who required over 10 units of packed red blood cells within the first 24 hours or who had early death despite continuous transfusion, it was found that 40% of older adults (age > 64) had massive bleeding that could not be diagnosed on the primary and secondary trauma survey as opposed to only 14% in patients under age 65 (p <0.05). The sources of occult bleeding were most often a fracture, contusion, or retroperitoneal hematoma without a pelvic ring fracture.5
There are several reasons why older adults are more prone to internal bleeding.
- They have weaker connective tissue and vessels so are more likely to sustain an injury and less able to spontaneously tamponade the bleeding sites.
- Elderly patients are much more likely to be anticoagulated (see figure below). Anticoagulation alone is an independent predictor of mortality in trauma patients.6
- Older patients who sustain life-ending injuries are more likely to present with “normal” vital signs than their younger cohort. Mortality remains higher for older adults even in the presence of normal initial vital signs.7
Here we will review 5 of the potential bleeding sites that should be considered among older adults and anticoagulated patients who present following a trauma. Some of them may be difficult to diagnose based on physical exam, and could easily be missed without the appropriate diagnostic testing.
An injury to the pelvic veins or arteries can lead to blood accumulating in the retroperitoneum and a retroperitoneal hematoma (RPH). It can occur alone or in conjunction with pelvic fractures. It can also occur higher up in the retroperitoneum or around the kidneys.
Patients at risk: Anticoagulated patients are at highest risk. It occurs spontaneously in anticoagulated patients with an incidence of 0.6–6.6%.8 It can also occur following a percutaneous coronary intervention with femoral arterial access, in the elderly, and in trauma patients.
Clinical Signs/Symptoms: Abdominal pain, severe low back pain, abdominal distension, or femoral neuropathy are complaints that should raise concern for retroperitoneal bleed. Patients with renal injuries and retroperitoneal hematomas around the kidneys may have hematuria. Grey Turner’s Sign (ecchymosis over the flank) or Cullen’s sign (periumbilical bruising) are the classic physical exam indicators of retroperitoneal bleed. However they have a very low sensitivity. Consider a RPH in high impact trauma patients with vital sign abnormalities but a negative FAST scan.
Work Up: Ultrasound is not great diagnostically because of the location of the blood. Of 92 patients who had RPH, ultrasound only detected the bleed in 48 of 92 (52%). CT is better for looking for RPH, but also imperfect. In one study, of 75 cases of RPH who underwent CT, the hematoma was only detected in 64 of 75 (85%). Although non-contrasted CT is useful for detecting acute and chronic blood, CT with IV contrast is preferable to help localize the site of active extravasation.9
Because of the low sensitivity, if a RPH is suspected but these modalities do not identify it, an exploratory laparotomy is recommended, especially in a patient with hemodynamic instability.10
Pelvic fractures should raise the concern for pelvic/retroperitoneal bleeding. However, as evidenced in the above case, it is possible for patients to have such bleeding in the absence of a pelvic fracture.
Treatment: Treatment can be conservative or operative. If a patient does not require immediate intervention, they should be monitored clinically with trending of their hemoglobin and serial exams. If intervention is needed, they can undergo embolization with VIR or go to the OR for operative management.
The most commonly injured abdominal organ in adults is the spleen, followed by the liver. The most common mechanism is a MVC. Bleeding can also occur from an injured hollow viscus or torn mesentery.
Patients at Risk: Trauma victims, anticoagulated patients, and those with splenomegaly (such as recent mononucleosis infections) are at highest risk.
Clinical Signs/Symptoms: Abdominal pain, tachycardia, hypotension, referred left shoulder pain, and diaphoresis should all raise concern for hemoperitoneum in a trauma patient.
Work Up: A FAST exam is commonly used for screening. If it is positive and the patient is unstable, this typically warrants laparotomy for surgical exploration. The FAST exam has a sensitivity of about 75% for identifying hemoperitoneum in blunt trauma patients.11 CT imaging is the best modality for stable patients as it can more precisely locate the intra-abdominal lesion.
Management: Many, but not all patients with hemoperitoneum will need to be managed surgically. For stable patients with low grade splenic or liver lacerations, they may only require close monitoring, trending of their hemoglobin, and serial exams. Patients with solid organ or vascular injuries may be amenable to angiography and embolization. Unstable patients or those with high grade injuries will require operative Intervention.
After a thoracic injury, blood can collect in the pleural space, limiting lung expansion and also causing increased intrathoracic pressure.
Patients at Risk: The patients at highest risk are those with penetrating chest trauma, blunt chest trauma such as from a MVC or deceleration injury, the elderly, and those on anticoagulants.
Clinical Signs/Symptoms: Vital sign abnormalities (tachypnea, tachycardia, hypoxia, hypotension), diminished lung sound, hyporesonance, rib fractures, and signs of external chest trauma should raise concern for a possible hemothorax.
Work Up: Bedside ultrasound and a chest X-ray can be helpful in diagnosis. Thoracic CT is highly sensitive to detect thoracic injuries after blunt chest trauma and is superior to a chest X-ray for visualization of a hemothorax.12
Management: The treatment is a tube thoracostomy. Depending on the output, the patient may require operative management.
This is an accumulation of pericardial blood, which can cause decreased ventricular filling resulting in tamponade and obstructive shock. In the setting of blunt trauma, hemopericardium is rare. In a study of 29,236 blunt trauma patients in the trauma registry, only 14 had acute traumatic hemopericardium, of whom 6 survived. An additional 4 patients had cardiac rupture without mention of hemopericardium, and 38 had insignificant or incidental pericardial fluid.13 This yields a prevalence of hemopericardium or cardiac rupture of only 0.06% for blunt trauma patients. In anticoagulated patients, hemopericardium can occur from bruised myocardium that slowly oozes and accumulates, causing tamponade.
Patients at Risk: Highest risk patients are those with penetrating chest trauma or anticoagulated blunt chest trauma patients.
Clinical Signs/Symptoms: Some of the classic signs of tamponade may be present (Beck’s triad), including muffled heart sounds, jugular venous distention, and hypotension. Other signs and symptoms may include sinus tachycardia, chest pain, dyspnea, a narrow pulse pressure, pulsus paradoxus.
Work Up: This injury is one in which an emergency physician with an ultrasound probe in their hand can perform wonderfully. Emergency physicians are reliable (96% sensitive, 98% specific, 97.5% accurate) at detecting pericardial effusion on bedside ultrasound.14
Management: Patients with traumatic pericardial effusions and tamponade should go to the OR emergently for control of the bleeding and evacuation of the hemopericardium.
Long Bone Injuries
Patients with a femur fracture can lose 500-1,500 cc of blood from the injury. One study showed an average of 1,200 cc of blood loss in patients with isolated femur fractures15 and even greater losses if there was injury to a major blood vessel. Fortunately, the incidence of vascular injury is low, around 0.1-2%.16 However, in any patient with a femur fracture, it is important to examine them thoroughly to determine if there are any signs of significant blood loss into the thigh.
Patients at Risk: There is a bi-modal distribution for this injury, including elderly females who fall from standing and young males after high-energy trauma.
Clinical Signs/Symptoms: These patients will typically have pain or a deformity that will lead the physician to evaluate for a fracture. Those at significant bleeding may lack pulses in the extremity, have an ankle-brachial index (ABI) <0.9, cool skin, severe pain, tight compartments, pain, and swelling in the femur.
Work Up: Measuring the ABI can help identify vascular injuries, which can be better characterized with a CTA if the patient is hemodynamically stable. Angiography is the gold standard and is best performed in the OR for concomitant intervention.
Management: To help reduce bleeding, the fracture should be reduced and immobilized to near anatomic alignment, which may require a traction splint. These fractures typically require operative fixation. Vessel damage can be managed with interventional radiology or operatively.
Older patients, particularly those on anticoagulants, are at high risk for clinically significant bleeding after from low-impact injuries. It is important to think about and assess for ICHs, but also for other sources of bleeding in the following areas:
- Thoracic cavity
- Long-bone fractures
Have a low threshold to perform CT imaging of these patients if you have a clinical concern for bleeding or if they are hemodynamically unstable. Have an even lower threshold for performing a bedside ultrasound to evaluate for bleeding based on the history and physical exam. Ultrasound performs particularly well to identify blood accumulating around the heart, lungs, and peritoneum, but does not easily identify blood in the retroperitoneum.