Case of the Month
January 2005

45-year-old female — shortness of breath

It is 1234 hrs. on a Monday afternoon when your tones hit. Your aid car is dispatched to a 45-year-old female who is having some difficulty breathing. While you are responding the dispatch center upgrades the call adding a medic unit. You arrive at a five-story office building and are led to the 4th floor by a security guard.

When you get to the 4th floor you find several co-workers who are huddled around an overweight woman who is in a chair slumped over to one side. She is conscious but seems lethargic. She is breathing deeply and quickly. She has cool moist skin and is pale. She seems unstable in the chair so you quickly listen to her lungs which are clear and moving good air. Your partner helps you lay her on the ground. Your partner checks for a radial pulse but cannot detect one. He finds a weak brachial pulse. You ask the patient if she has any numbness or tingling anywhere and she states she does not. Further examination reveals the following:

LOC	—	Conscious but lethargic
RR	—	44/min
HR	—	144/min weak
BP	—	80/palp
Skin	—	Pale, cool, mildly diaphoretic
HEENT	—	Pupils-Normal and reactive to light
Chest	—	Unremarkable
Lungs	—	Clear lung sounds to the bases
Adb	—	Unremarkable
Ext	—	Mottled and cyanotic
Pulse Ox	—	Cannot get a reading

The clear lung sounds make you wonder if the patient is merely hyperventilating, however the rest of the signs and symptoms don’t support this assessment. You decide that this patient is SICK based on her clinical indicators and begin rapid treatment. Your partner administers oxygen via a non-rebreathing mask at 15 L/min while you update the incoming medic unit of the patient’s status.

The patient reports that her shortness of breath is not getting worse. She also begins to complain of a sharp pain under her right breast. Due to the extreme nature of her breathing difficulty you prepare your bag-valve mask in case assistance is needed. You gently place her in shock position because of her low blood pressure and rapid heart rate.

S	—	Sudden onset of shortness of breath
A	—	No known allergies
M	—	None
P	—	No significant medical history
L	—	Ate lunch about 30 minutes ago
E	—	She had just gotten up from her desk when the SOB started.

The medics arrive and have brought a gurney with them. They immediately start an IV of lactated ringer’s and flow the fluid wide open. She is placed on the heart monitor and found to be in a sinus rhythm at 148 with occasional ectopy. A second set of vital signs reveals similar findings to the first set. You are now able to get a pulse oximetry reading of 83%. The patient is gently placed on the medic’s stretcher and taken to the rig. The medics gain permission to intubate the patient and transport her to a local hospital. During transport she goes into respiratory arrest quickly followed by cardiac arrest. The team is not able to resuscitate her.

Pulmonary Embolus
A pulmonary embolus (PE) is a blood clot that is set adrift in the venous circulatory system and travels through the heart and into the vessels supplying the lungs. Once in the lungs, the embolus lodges in the increasingly narrowing passageways, blocking the blood flow distal to that point. This can result in minor blockage, which may be asymptomatic, or it can create a severe loss of circulation. The area of the lungs that is affected by a PE can no longer exchange carbon dioxide for oxygen which decreases the effectiveness of the respiratory system.

The most common cause of PE is a blood clot that forms in the vein of the upper leg, often referred to as DVT or Deep Vein Thrombosis. DVT often develop because of long periods of inactivity, such as a long airplane flight or after extensive lower extremity surgery. They can also occur spontaneously. When DVT is suspected a patient must be handled very carefully. Since it is common for more than one clot to occur at a time, rough handling may further endanger the patient. A PE also may be caused by a piece of tissue that breaks free and is carried by venous blood flow to the lungs, for example, a femur fracture where the vein has been lacerated and a small piece of the vein wall or surrounding fat is carried to the lungs.

A confusing finding you may find with a PE is clear lung sounds. The patient will look SICK and have rapid respirations, but the lungs are usually clear. This is because the air passages themselves are rarely affected by the condition--only gas exchange is affected. Often, mistakenly, these patients are thought to be suffering hyperventilation syndrome.

The lesson learned from this case: Never make a steadfast assessment based on one finding (e.g., the clear lung sounds in this case). Your job in the field is to treat what you see and leave the diagnosis to the hospital staff. As an example: If you are unsure whether to use a mask or a cannula, use the mask. If you are unsure whether the condition is hyperventilation or a PE, treat as a PE – you can always alter your care when the situation seems more stable. Never have a patient who is short of breath breathe into a paper bag! This ‘old fashion’ treatment for hyperventilation syndrome can quickly kill the patient who is suffering from a PE or any other major lung insult.

View more information on pulmonary embolism — eMedicine.com (external link)