Feb
32 year old nurse who had rheumatic fever as a child noticed a persistant tachycardia and lightheadedness. Upon examination, chest x-rays showed an enlarge left atrium and left ventricle. ECG analysis showed atrial fibrillation. There was also mild pulmonary congestion. Cardiac evaluation resulted in the following information:
Cardiac output (CO) 3.4 L/min
Blood Pressure (BP) 100/58 mm Hg
Left atrial pressure (LAP) 16 mm Hg
Right ventricular pressure (RVP) 44/8 mm Hg
Heart sounds reveales valvular regurgitation.
1. Based on info provided, which A-V valve is incompetent, allowing the regurgitation?
2. Which heart sound would be pronounced and lengthened?
3. Using surface anatomy, describe location valvular disorder could best be heard.
4. If other A-V valve were incompetent instead of this one, woudl the CO, BP, LAP, and RVP be different? If so, how?
5. What are the causes of the tachycardia, light-headedness, and mild pulmonary congestion?
6. Compute the pulse pressure (PP) and mean arterial pressure (MABP) for this individual.
PP=
MABP=
Answer:
1. Mitral heart valve
2. S1 would be prolonged
Mitral regurgitation sounds like this: http://www.youtube.com/watch?v=MMJBSd5Z_…
3. Between the 4th and 5th ribs, left sternal edge. Pansystolic murmur at the apex. Chest Xray could show an enlarged left atrium and left ventricle.ECG would show a broad P wave of left atrial enlargement
4. The C/O would be decreased. Blood pressure would be a bit lower and LAP/RVP may be slightly lower, but often normal.
5. Atrial fibrillation and decreased C/O and BP would cause dizziness.
Haemoptysis with pulmonary congestion is a late feature, but pulmonary congestion happens if the valve does not close properly, this causes blood to be pumped back into the left atrium when the left ventricle contracts.
If the leak is huge, it results in an increase in the pressure in the atrium. Hypertrophy of the wall of the atrium can occur and the atrium might dilate. A back pressure of blood might then cause congestion of blood in the pulmonary veins which bring blood to the left atrium from the lungs.
6. PP is systolic pressure minus diastolic pressure, so 100- 58= 42
Mean arterial pressure is [( 2 x 58)+ 100] /3= 72
(Double the diastolic pressure, add the systolic number to it and divide that number by 3. This will give a very close approximation.
Answer:
Oh practice nurse, you have to do better than that.
Tell the Educator you don't comprehend and I'm sure He/she will have some empathy for your courage and help you.