“Ambulance 34, Ambulance 34. 452 Smithfield Street for the 34 year old male with chest pain and difficulty breathing. Delta-Level response. Medic 72 will be your backup. Time out 14:35”
Ambulance 34, a BLS level ambulance responds from their designated system-status management post to the residential neighborhood where the call came from. Upon their arrival at the single-family home, they are directed into the kitchen through the garage by a woman who identifies herself as the patient’s wife. Once inside, they find the patient sitting upright in a kitchen chair holding his chest and grimacing in what appears to be pain. He doesn’t look good.
“My chest… it like… really hurts… a lot…” the patient says. His words come slowly and deliberately. He doesn’t look like he’s able to take a full breath and his face twists up with pain after every inspiration. He seems very anxious.
“I was mowing the grass… And all of a sudden… it just started… hurting… a lot.” The patient stammers. He points to the left side of his sternum and coughs as he talks. “I got dizzy and I am not really able to catch my breath… I feel like I’m going to… pass out…”
The EMTs decide to keep the Medic unit coming and continue assessing the patient as they check his vitals. Through questioning the patient, they find out that he describes the chest pain as being “Sharp like a knife” and that it exacerbates, or worsens, to breathing in. They find that the pain is just to the left side of the sternum about the level of the nipple line. On their assessment, they find that the patient’s skin is pale, cool, and moist. His pupils are PERRL and he has no Jugular Venous Distension. His trachea is midline and mobile and both of his lungs are clear. His abdomen is soft and non-tender and he has good pulse, motor, sensation, and temperature in all 4 of his extremities. The EMTs did notice that the patient’s pulse was slightly irregular and elevated at 126 and that his blood pressure was elevated at 146/84. The patient’s oxygen saturation was 93% on room air. His only medication is a “testosterone gel” and he has no allergies.
Following their regional protocols, the EMTs apply a 4-lead EKG and obtain a 12-lead EKG. They transmit the EKG to the local cardiac hospital and print out a hard copy for the responding paramedics. They place the patient on 4-LPM oxygen via nasal cannula with ETCO2 sensing capability and see the patient’s pulse-ox improve to 98%. The ETCO2 waveform has regular morphology and shows a respiratory rate of 24 shallow breaths per minute.
As they’re finishing their assessment, the paramedics from Medic 72 arrive. The EMTs report their findings to them and prepare their cot for transport. The medic reviews the 12-lead and says that it “looks good” to her while her partner asks the patient a few more questions.
“Have you recently been sitting more than normal? Have you travelled anywhere lately? What about any recent injuries?” she asks.
“Well, now that you mention it… I just got a new job in the back office at work. I’m sitting a lot more at a computer than I use to when I was on the floor. Also, I did sprain my knee at the gym the other day… I started working out when I noticed the new computer job was putting a few new pounds on me” the patient says. The oxygen seems to be helping him speak.
One of the paramedics rides in with the crew of Ambulance 34. Working from her diagnosis of a probable pulmonary embolism, she continues the oxygen and cardiac monitoring and establishes a saline lock in the patient’s right antecubital fossa. The medic administers 5mg of morphine to the patient to help control his severe pain and has the ambulance transport the patient to the cardiac hospital using the emergency lights and siren.
Once at the hospital, the physician orders a standard panel of labs which include a D-Dimer and a stat troponin level. He also orders a stat chest CT scan. The patient is diagnosed with a pulmonary embolism and started on anticoagulant therapy in the ED before admission to a monitored inpatient unit.
A pulmonary embolism, or a “PE” is not necessarily a disease in itself, but is a symptom of an underlying condition. It results from a blockage in the pulmonary artery or one of its larger branches that blocks some or all of the blood flow from the right ventricle of the heart to one or both lungs. The condition can cause anything from mild symptoms to sudden death but often presents with all or some of the signs and symptoms presented above. (1) This blockage can be caused by a number of things, such as a blood clot, a small piece of fat, amniotic fluid, or other problems.
Patients complaining of pulmonary embolism generally present with some or all of the following signs and symptoms: (2)
- Usually a pulmonary embolism presents with a sudden onset of symptoms.
- Chest pain – Usually “sharp” and located on one side of the sternum. The pain generally exacerbates to inspiration. Patients sometimes describe the pain as a “burning”, an “ache” or a dull heaviness.
- Tachypnea – Rapid breathing which may be shallow due to the pain.
- Tachycardia – Rapid heart rate
- Hypotension – Low blood pressure
- Sudden cough, possibly producing blood or bloody mucus – Hemoptysis
- Shortness of breath
- Cyanosis – Bluish skin color
- Pale, cool, and diaphoretic skin
- Dizziness, lightheadedness, or fainting
- Leg pain, redness, or swelling, symptoms of a deep vein thrombosis
Providers should also look out for atypical presentations of PE, which can result from a sudden lack of oxygenated blood flow to the body and can be such presentations as seizure, syncopal episode, or cardiac arrest.
Field EMS care for pulmonary embolism depends upon the presentation. For patients who present with an altered mental status, resuscitation up to and including CPR is indicated. Otherwise, care is supportive. Support oxygenation by maintaining SpO2 in the 97% and above range using as little oxygen is required for prevention of hypoxia. Hypotension should be treated with just enough fluid to restore blood flow, although it is wise to limit fluid to under 1 liter in order to avoid putting undue strain on the right ventricle. In cases of hypotension with suspected PE, vasopressors are indicated in hypotension refractory to fluid administration but may cause an undesirable increase in heart rate. (3) Pain management using narcotics such as Morphine and Fentanyl may reduce patient anxiety. Administration of nitroglycerine and aspirin have not been shown to be an effective treatment for PE (4) although many EMS protocols may call for their administration in medical protocols for chest pain of unknown origin.
Definitive treatment of PE is performed at a hospital through removal of the emboli from the pulmonary vasculature by various means, such as through anticoagulation therapy, thrombolytic therapy, or in some more rare cases, surgically. Inpatient admission is usually, but not always, required. Definitive diagnostic techniques include lab tests for D-Dimer levels, troponin levels, CT scan, and possibly transesophageal echocardiogram.
Since mortality caused by PE occurs often within minutes to hours after onset of symptoms, it is important for paramedics and EMTs to be able to consider PE as a potential diagnosis as it remains a condition that carries a high rate of morbidity and mortality. Be sure to consider PE as part of your differential diagnoses for patients complaining of chest pain, syncope, seizure, and cardiac arrest.
- Pulmonary Embolism - Daniel R Ouellette, MD – Medscape.com
- Pulmonary Embolus – MedLine Plus – Accessed 3/16/14
- Treatment of Acute Pulmonary Embolism – Tapson V MD, www.Uptodate.com – 8/12/13
- Pathophysiology and treatment of haemodynamic instability in acute pulmonary embolism: the pivotal role of pulmonary vasoconstriction – Yvo M. Smulders – Cardiovascular Research 48 (2000) 23–33
For more on differential diagnosis for chest pain, see: “Call PAPPA for Chest Pain – A Helpful Mnemonic for Paramedics and EMTs”