How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dr. Chip Your Own Question
Dr. Chip
Dr. Chip, Board Certified Physician
Category: Medical
Satisfied Customers: 36174
Experience:  20 yrs. in practice, includinge surgery, general medicine, addiction medicine and pain.
Type Your Medical Question Here...
Dr. Chip is online now

A Post Polio Patient on a -level ventilator is to have an

This answer was rated:

A Post Polio Patient on a Bi-level ventilator is to have an arterial blood gas test to check for CO2 retention. Should the patient be tested seated, supine and/or should the patient be put on his bi-level for 30 minutes prior to the test?

Hi and sorry for the delay here

The best option would be to have the patient supine since in a seated position the pressure of the abdominal organs on the diaphragm could increase the CO2 retention a bit. But basically either supine or seated the blood gas values should give a reasonable idea of the amount of CO2 retention

And yes the bi-level ventilator should be on for 30 minutes before the test since that would best determine whether the settings are appropriate for a given patient

Customer: replied 3 years ago.

Does not answer what I was asking sadly. We said neuro physio believed he was co2 retaining during the day. He uses the ResMed S9 for sleeping. I am surprised a Chief Resp Physiologist would do an abg to see if the settings are correct when he has ResScan and Pulseox readings. Your further help would be appreciated on this to increase the Rating. In fact his CO2 was low and he reduced the Ipap from 18 to 17 and increased the EPAP from 5 to 6 although his result sheet said it was 8. The compliance was reported at 5.5 and it has been less than 4.5 for three months. I really would appreciate further information on this or where I can find out more so that I can speak with more understanding to his GP as we desperately try to find out why for the last three months he has been taking the mask off 'I cant breathe'. So how do we get a check for CO2 retention during the day please? I do appreciate your help. I am Founder of Polio Survivors Network 1996.

No problem with working with you Hilary but you didn't give me all that information at first so I could only answer your question as first stated.


First question--has the patient had spirometry to check the lung function? And what were his O2 levels both on and off the mask?

Customer: replied 3 years ago.

We have our own Pulseox downloadable and strangely .. he had heart attack and stents fitted Dec and Jan.. in the last couple of months when I have put pulseox on and its not dislodged we have normal 90 to 95 readings both on and off the ventilator. I have scanned pdf of three nights one showing on and off times on vent couple of hours each which am sharing with his NeuroPhysio and Chiropractor both private monthly appts. We dont have insurance.Last night he would not keep it on saying machine is not working right I cant breathe and two previous nights 42 minutes then took it off. He has scoliosis and we have neuro physio report of weakness and difficulties breathing but the Chief Resp Physiologist has not examined him naked or done full LFT's, and I am researching to find information that I can take to our BP as we are looking at possibly having to go to Lane Fox Unit. He has mixed sleep apnoea and Parkinsons as well. Neither of us are seen by a specialist in Post Polio as no-one locally has that knowledge. I understand this is really complicated but I am worn out with researching to find the right info and place to get him help.

OK Stick with me Hilary. Is the Chief Respiratory Physiologist the same as a pulmonologist?

Has he had a spiral ct can of his chest?

Customer: replied 3 years ago.

He is not the Respiratory Consultant - like USA Dr. John Bach.... He is the man that does the LFT's. He is the only Physiologist at our hospital. Being honest when we first met in 2012 his 25 years ICU South Africa and his I know polio and post polio we were relived at last to have found someone with more knowledge. There is far less knowledge and understanding in the UK than USA about polio and post polio. I have presented in San Francisco, Miami and St. Louis 3 times and at the 2nd European Polio Union Conference in Amsterdam last June. But the more we see him and the more we speak to him I dont think he does have hardly any knowledge on polio, post polio and even bi-level use.

As for tests... we permanently came to UK in 2008. Since 2012 He has had no LFT's other than FVC, Mip and Mep all seated in wheelchair. Four ABG that we now learn have all been after 30 mins on ventilator - we never noticed. His settings only changed this last time from abg low PCo2. Last visit I did insist on supine but he did one FVC seated and then one supine. No physical examination at all. One consultant appt in 2012 and we just found out that none since because they expect Richard to be referred to them if the CRP deems it necessary. GP got same response from Consultant secretary last week, we will check see if he thinks necessary. I am now querying his not wanting Richard to be seen because it will bring out his lack of knowledge

OK Hilary--before I try answering what you originally wanted to know can you just clarify it for me please? All I can do for now is give you my further thoughts but I can't specifically help with his consultants and what they may or may not do about the problem
Customer: replied 3 years ago.

We reported that we and confirmaton from Neuro Physiotherapist that he appears to co2 retain at times. Now we have seen the report from the last Chief Respiratory Physiologist test [we had not had copies or were aware before that they existed] his abg have always been done 30 minutes after NIV ventilation. When you look at all the clips powerpoints etc it does not mention putting patients on vent unless they are in hospital and changes in settings have been made and then wait 30 minutes. So we think he should have abg done without ventllation to see what his level is during the day. What do you think? Understand that you are not specialist so your opinion and where might I search for more info. I am very grateful for your help, believe me. After six hours searching on the internet I was getting very tired and you have lifted my spiritis.

OK but this time Hilary, if I haven't covered all the bases, please come back and tell me to continue rather than rating me poorly

First off, if anything this is not a CO2 retention problem--that wouldn't cause his feeling that he can't breath. He needs an ABG done while he's off the ventilator and while he's having a shortness of breath feeling. It would also be important to get the O2 measurement while he is on the ventilator for comparison. He also needs a full LFT/spirometry test and he needs a spiral ct scan of the lungs since small pulmonary emboli that can't be detected on chest x-ray may be a component of the problem here.

He needs to be seen by a Pulmonogist for a complete evaluation at this point.

Dr. Chip and 3 other Medical Specialists are ready to help you
Customer: replied 3 years ago.

Thankyou very much for your time. It is really appreciated. I can now get evening meal and stop searching for info. Rated highly now.

Thank you Hilary but keep in touch and let me know where things go