What is the purpose of ventilation perfusion scan?

Posted on Wed, 10 Jun 2015 in X-ray, Lab tests and Scans
Question: What will cause your oxygen level to drop low enough for a doctor to order a " ventilation perfusion test asap? also will it cause you to be tired all the time as well have a cough that is a very deep cough and sometimes make u feel like you are checking ,, my blood'reasure sometimes will go as high as 121 - 135 on the bottom number ,would that be a symbol of the low oxygen level in the daytime as well ? Oh he already has me on a oxygen concentrator at night for about 4years now.

Answered by Dr. Chobufo Ditah 30 minutes later
Brief Answer:
What are oxygen saturation numbers?

Detailed Answer:
Hi and thank you so much for this query.

A ventilation perfusion scan is a test that maps out all the blood vessels in the nouns. This is used to determine whether there are blockages in the circulation that might be causing increased pressure in the lungs called pulmonary hypertension. The most common complication of pulmonary hypertension is heart failure which would lead to symptoms of easy fatigue, inability to climb stairs, swollen limbs etc. High blood pressure readings suggest hypertension and not a sign of low oxygen levels.

In all, this test is not to show low oxygen levels but to look at the circulation to see whether it has any abnormalities. This is mostly used when pulmonary hypertension is suspected.

I hope this helps. I wish you well. Thanks for using our services and do feel free to ask for more information and clarifications if need be.
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
Follow up: Dr. Chobufo Ditah 1 hour later
Thank u for getting back to me,i failed to tell u that the lung doctor I see has already told me about 4years ago that I do have pulmonary hypertension, and that he thought I also may have sleep apnea however when I did the sleep study I didn't have it so they had a person come to my home and taped that thing on my finger to tract my oxygen levels at night and he put me on a oxygen concentrator at night ,,as well ed2different inhalers,, I started having a cough about 2years ago, that sounds like thedeep cough children get they are very young and would be put in the hospital ,,one doctor thought it might be from the medicine for my blood pressure so my rHeart rDoctor took me off it put me on a different one that wasn't as good, didn't stop it, so after 2 years and no relief put me back on another one that was stronger, but now the chronic cough has gotten more frequent as well as causing to cough to the point my chest starts getting tight, my throat feels as if I am choking and nothing comes up, you can hear the rattling in my breathing,, it dosnt matter if I am laying down, on my side or back, up doing housework, talking on the phone or going outside,i will start coughing and it seems as if I will never stop! Is this realted to the low oxygen ? I didn't realize I was not getting the oxygen I should have during the daytime, never thought they were related to that,i just noticed I wasn't XXXXXXX to do the things I could last year, due to getting tired and out of breath, and the coughing was getting worse, as well deeper, about 2 months ago I went to my family doctor who said that he was hearing something in my left lung, had a chest xl-ray but didn't show pluralism and told me to go see my lung doctor ,and he had the nurse walk me down the hall with the thing on my finger and said the oxygen level drops lower than it should, so is all the other problems I have related to that ? It also stays on my left side,, oh he also ordered a echocardiogram 3d all I know is I am sick and tired of begin sick and tired,,i used to be XXXXXXX to walk every morning at a park where you would be on level ground then up a small hill thing back, it was 5 miles altogether ,I would do this everyday for over 3 years and loved doing that, also have serial flower gardens around my yard that I kept weed free and now can't because of getting tired after only a half hour or so, that stared over a year ago, couldn't walk at the park since 2012,,I'm not sure I mentioned i am on my 2nd pacemaker I got my first one in 1998 ,I had been passing out for no reason,i was seen by 3-5 different doctors, all kinds of test and after a year of no results my husbands heart doctor ordered a tilt test and before they injected anything in me ,she had me in a standing position and after 13 minutes I told her I was going to pass out, she said no your not, its just your nerves,i then told her my stomach was starting to cramp and to lay me back down that I was going to pass out, she didn't and I did the next thing I was laying down and the doctor telling me I had broke the record that he had never had anyone whose heart stopped for a minute 16 seconds while taking the test ,he then said I had to have a pacemaker,i asked him why, and he said because every time I passed out my heart would stop and was lucky it hadn't stopped as long as this time, I asked if that would stop me from passing out, he said no but it would keep my heart from stopping, this is my second one and it was put in 2007,,, so was that a warring that something else was going on and it just took time to start showing the other symptoms? Are all these things related to each other? if there is some kind of blockage how and who treat it? and what type of treatment would it be? I hope and pray you can give me a answer to my questions, every time I would ask one doctor they would just tell me to ask the other one, and it is very frustrating!! thank you for taking time to read this,,,
Answered by Dr. Chobufo Ditah 10 hours later
Brief Answer:
The tests would provide guiding answers to us!

Detailed Answer:
Hi and thanks for the detailed follow up information.

I have reviewed this information fully. This is suggestive of a heart disease caused by the lungs. With the vessels in the lungs being narrow, the heart needs to pump at higher pressure than usual and this explains why the blood pressure has been rising. Pumping blood at higher pressures than usual would lead the heart into failing and may explain why you have serious difficulties walking around and easily getting short of breath.

I understand your health is not the best and there is no straight forward answer as to what the exact cause is. I will suggest we wait on these two tests as they would tell us with precision what the state of the blood vessels of the lungs is. The cardiac ultrasound would tell us what the functional state of the heart is. These put together would be guiding enough for further explorations and treatment plans. For now, let’s wait on these before making further plans.

I hope this helps. I wish you well.
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
Answered by
Dr. Chobufo Ditah

General & Family Physician

Practicing since :2009

Answered : 6252 Questions


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