Question

Clinical Scenario (from part 1)

Meera is a 24 year old woman who has been studying at a local university. She recently returned from a 14 hour flight to Delhi, where she had been visiting family. She came to your emergency room worried that she is having a heart attack; she describes 2 hours of a sharp pain in her chest and back, which is worse when she takes a deep breath. She states she is having a hard time breathing. Her vital signs are as follows: Blood pressure is normal at 120/72, pulse elevated at 112, normal body temperature of 98.1℉, and an increased respiratory rate of 40. Meera’s past medical history is unremarkable. She has never been pregnant, and is currently taking an oral contraceptive to prevent pregnancy. In addition to her oral contraceptive, she takes a multivitamin daily and sometimes uses ibuprofen for menstrual cramps. She occasionally drinks alcohol, is a ½ pack per day smoker, and denies any illicit drug use.

Treatment (from part 2)

You have ordered a set of arterial blood gases (ABGs), a D-dimer, an EKG, and chest imaging for Meera. Her EKG did not show evidence of cardiac ischemia or myocardial infarction, and her Chest CT revealed a large pulmonary embolism. Her D-dimer was elevated. Her ABGs are as follows: PaO2: 75 mmHg Normal range: 80–100 mmHg pH: 7.5 Normal range: 7.35–7.45 pCO2: 30 mmHg Normal range: 35–45 mmHg HCO3: 22 mmol/L Normal range 22–26 mmol/L

Rationale (part 3)

Pulmonary emboli are a disorder of both perfusion and normal lung function. Explain in one to two sentences why a disorder of one of these physiologic systems will impact the other. Would you classify the alteration in normal lung function as a disorder of ventilation or of diffusion? Explain your rationale.

Answer 1

Answer1. Pulmonary emboli is the problem where a blood clot comes in the bloodstream of arteries thereby blocking the flow of blood. Here the artery is the pulmonary artery. This results in shortage of breaths.

If the blood from the pulmonary artery won't get oxygen from lungs, it will affect the heart function also leading to severe pain and heart shock.

The irregular flow of blood through the pulmonary artery creates a gap or space thereby ratio of ventilation to perfusion increases resulting in mismatch of gas exchange procedure.

Answer 2. The normal lung functioning is in gas exchange of running boood through them. The alveoli helps in this system by using the technique of difference in partial pressure of the two gases(oxygen and carbon dioxide).

To have an effective gas exchange, the alveoli must be ventilated and perfused timely, where ventilation (V) means the flow of air into and out of the alveoli and perfusion (Q) means the flow of blood to alveolar capillaries. They have a fixed ratio in normal functioning of lungs.

But in case of pulmonary embolus, that is, in Case Of Any kind of blood clot in the pulmonary artery causes changes in the bllod flow and affects this ratio that is, it is increased. This changed ratio will cause hypoxemia( low level of oxygen in blood).