Non-invasive ventilation and respiratory critical care: panel discussion

Speaking at Hospital Healthcare Europe’s Clinical Excellence in Respiratory Care event, our panel of three experts considered the role of critical care in respiratory medicine. Dr Andrew Chadwick, Jane Scullion and Dr Phyllis Murphie PhD discussed how guidelines and best practice for treating respiratory patients in critical care have changed since the advent of non-invasive ventilation, as well as the lasting impact of the Covid-19 pandemic in this field.

With increasing use of non-invasive ventilation over the past 30 years, not to mention the wide-reaching impact of the Covid-19 pandemic, respiratory critical care has seen its fair share of change in best practice, which three Clinical Excellence event panellists know all too well.

Dr Andrew Chadwick is a respiratory and critical care consultant at Oxford University Hospital NHS Trust, where he is part of the nationally recognised special airways clinic. He reviews over 300 severe asthma, chronic cough and complex breathlessness patients each year and has a vast experience in critical care, as well as a self-professed love of non-invasive ventilation (NIV).

Independent consultant respiratory nurse Jane Scullion spent many years working at Glenfield Hospital, part of the University Hospitals of Leicester NHS Trust, across the TB service, asthma clinics, COPD services and interstitial lung disease clinics. In her early career, she was heavily involved in critical care and NIV on respiratory wards and, more recently, has worked in medical negligence and long Covid clinics.

Dr Phyllis Murphie PhD is an independent respiratory nurse consultant working in Dumfries and Galloway in Scotland. She specialises in sleep medicine and NIV, having introduced the NIV service into her hospital many years ago. In 2020, she led a respiratory nursing team through the Covid-19 pandemic and introduced changes to ensure the effective delivery of respiratory care during this challenging time. 

Chaired by Garry McDonald, respiratory pharmacist at University Hospital Crosshouse in Scotland, the panel consider the trajectory of guidelines for managing respiratory failure, their take on ensuring patients respond well to NIV, and key learnings from the Covid-19 pandemic that are still in use at their hospitals today – including the somewhat divisive proning technique.

What’s your take on the trajectory of guidelines for respiratory failure and where are we now?

Dr Chadwick: It is fascinating how our mechanisms of treating respiratory failure have changed or haven’t changed and how we got here. If we wind our brains back, NIV starts getting developed in the late 80s and it starts to be used at home. It was late in the 90s when it exploded onto the scene in hospitals, with the work out of Leeds from Plant showing the staggering effect on COPD exacerbations. Number needed to treat: three to save a life. This is eye watering, it’s fabulous.

Then there is a real push in the early noughties of how far can we push these machines? What can we do? What works and what doesn’t? Then, you start getting a mixed signal in true acute respiratory failure. The narrative starts becoming: are we overusing this? Are we delaying intubation? Are we holding back, holding the patient in a period of risk?

There was a bit of controversy about it, and that built. Then, in 2020, a systematic review in JAMA pointed out that there are lots of small studies, put them all together, and what you start getting is a real signal of benefit of delaying intubating, a signal of benefit of saving life, and that helps us go forward.

Then Covid comes. A real challenge came out about are we sure we have got this right? And you had University College London at the start of this – we copied them in Oxford – saying, let’s hold people on continuous positive airway pressure (CPAP), let’s try and avoid incubating. Partly because we were worried we were running out of oxygen and I’m sure a lot of other places were too. And then the trial showed that this really does help to avoid intubating.

And now I think we’re left in a real limbo. I hope that gives a sense of where we are now, as I think where we are now is really interesting. If you were to go into the Berlin ARDS definition of guidelines, I think you’d find NIV spoken of in relatively negative terms in respiratory failure, apart from COPD, pulmonary oedema and cardiogenic shock. But I actually think in the real world, with really good data that I’ve hopefully just pinpointed, you find a much more balanced view and indeed a view that’s increasingly going: I wonder if we should hold, hold, hold off intubation.

If you look at the COPD literature, NIV to treat is unbelievably good compared to almost anything else in medicine. Initial trials using a pH of around 7.3 show significant improvements. I think in treating acute respiratory failure, increasingly, NIV can be a really good adjunct. Intubation is clearly the end of the road.

How have you seen the NIV technology change over time?

Ms Scullion: I remember the great big machines that you couldn’t carry around, trying to prop them up next to patients to ventilate them to start with. Now, we have lots of small portable devices, not just in a hospital setting, but people with longer-term conditions are also managing at home, especially with the LSAs [Lung Support Assistants] travelling with it.

It has been life transformative. Things do evolve. The nicest thing that came out of Covid was that respiratory proved that we could do the research, could look after the patients and could get results out of it that will alter as time goes on. We didn’t have enough critical care beds and the ordinary nurses with no respiratory background stepped up and did this, as did the doctors on the wards and pharmacists and physios. We ran almost mini high-dependency units wherever we could run them.

Dr Murphie: It’s remarkable, the evolution of the non-invasive ventilation story. From the days of my first job, I came to the consultant, who had two NIV devices in a cupboard and he didn’t know what to do with them. So, he said, ‘Phyllis, do you think you could arrange some training’, so it started from there.

When these devices were retired, we moved up to the next version, and then the next version, so the whole evolution of the devices that we used in secondary care, particularly during Covid, was a very steep learning curve for a lot of people because we had to do this outside of critical care in the wards.

Covid was the beginning of respiratory support units evolving. We spent hours and hours training all the staff to come in and be able to manage ward-based CPAP and NIV quite safely. For me, NIV really came of age at that point in time in terms of people’s understanding of it, when to use it and when not to use it.

What are your top tips for getting a patient onto non-invasive ventilation and accepting it? 

Ms Scullion: It is really difficult when you have a patient in extremis, and you are going to put something onto the face. It is difficult when patients are really ill – you have to have a lot of time to get them to accept things.

I have often thought that as part of pulmonary rehab, especially with COPD patients, we should take these things in before people need them so they can see them and get used to it and feel what it is like because you can’t make a rational decision when you are extremely ill. We know some patients won’t tolerate it although a lot do. It can be uncomfortable, it dries your mucosa and there are all the other side effects. So, it is time and patience.

Dr Murphie: Something that is really important is knowing how to mask fit properly. Being able to make sure they have got the right size mask on, because then you start getting pressure sores and things on the nose. Fitting the masks and making sure that people know how to fit them properly and not do harm is a really important skill to learn as well.

It takes a certain level of skill to acclimatise your patient onto the therapy. You have to be patient, work out the fears and talk them through it. Sometimes, you have to start with the sub-optimal measures to get them comfortable and confident enough to wear the mask. You give them reassurance that this is something that works really well; it could shorten the length of time they are in the hospital and make the other therapies work better as well.

Dr Chadwick: This is one of those times when you really need to add in all your confidence, and you need to get the patient to buy into it. Don’t underestimate the power of reassurance and the power we have as healthcare professionals to do that.

So, coming in, being reassuring and then asking for one hour of NIV and really trying it. Then you can judge the blood gas, and you can go back to them and their family, and say, ‘look, we really tried, but we’re not winning with this, so let’s not’.

Or you can say, ‘Actually, look, we have really made a big progress; our pH has jumped from 7.1 to 7.15, so that’s a huge difference’. Then suddenly, you are in a new conversation saying, ‘well, actually, I’ve got physiological proof that this works for you, so work with me. This is going to be brilliant’.

How do you ensure the proper treatment is given to patients at the right time?

Dr Murphie: Having outreach teams is really important. Making sure that we can talk to the teams in, say, the combined assessment unit. They want to see patients early. If they are starting to struggle, and you can see that their blood gases are going off, then we want to know early on.

Getting in early and trying to work with the patient to reassure them that there is something worth trying to see if they can feel better. They can turn a clock back very quickly and start to see improvements if it is applied early enough and not too late.

Dr Chadwick: You just jumped onto one of my pet peeves. Number needed to treat is unbelievably good – better than almost everything else in medicine. Increasingly, what you are seeing is drift in all of us, in every clinical practice, we are just holding it back later when the patient is sicker. Early is better. You get in there early and stop the hypercapnia, if that’s what you’re doing with NIV. It’s much easier than coming in when they are really down the line. It’s a real pet peeve of mine: what are we doing holding back? There is a kind of odd culture of holding NIV back.

Ms Scullion: The acceptance of patients is better if they are not confused and not fighting it and not agitated and not desperately ill. That has to be the best option to do it as soon as possible. 

We want to do the best for the patients in front of us, and sometimes NIV is the best treatment that you can give, and it stops a lot of other things. Our patients nowadays do get fully ventilated and do get off ventilators, but not in great numbers.

A lot of them do poorly, and it is not a terribly nice prognosis at the end for the family to cope with. So, NIV, for me, is a nicer option because the patient is still in the room with their loved ones.

What were some of the main ways respiratory critical care changed during Covid?

Ms Scullion: I was so proud of the respiratory community during Covid because we had to get on with it. A lot of the decisions were made by clinicians. We did for patients what we could and everybody – across the board, pharmacists, physios, put their shoulder to the wheel and did it. Even in patients when we were proning, and things like that, you know there were 10 or 12 people proning a patient.

I mean, proning was something where, if you can say, good came out of Covid because it worked. It’s probably quite an old technique. I’ve seen the pictures of the old machines where people were turned in the machines and had a mirror so they could see up or a mirror that could see down. So, it has been around for a long time and often, just because it’s old, doesn’t mean it’s not good.

Dr Chadwick: It is perceived as an old trial. I was working out in Paris briefly on a long placement and they, honestly, were flabbergasted pre-Covid that we don’t just prone everybody. And in England, the problem is – and this is common across units and there’s no judgement because these are world-class British units – but we would always say things like, ‘oh, it’s not safe, you might dislodge, you might do something’. And you’re absolutely right, Covid put that all to the wind.

Work done by people like UCL really nudged the needle back to say, ‘come on now, prone them, it really works. It buys you space to ventilate them kindly and keep within those safe parameters’. So, you’re absolutely right, Jane, it’s another fabulous example of where real positives came out of Covid and essentially just reset that needle and how we treat acute respiratory failure.

Tell us more about the multidisciplinary team’s role in respiratory critical care during this time

Dr Murphie: We had the Army logistics teams come in and they basically organised and changed the flow of the hospital. Dumfries and Galloway is a brand new hospital with all single rooms, which was fantastic. The air changes in each single room six times per hour, so we actually really didn’t have a huge amount of in hospital transmission.

We moved the respiratory ward right along to the other end of the hospital so we were very close to the combined assessment unit. When patients were being moved, there was a green flow and we had a red flow. The green flow was the clean way to go and the red for the contaminated way. So, that really changed the way in which we actually managed patients in the hospital and we had a command control structure that did work really, really well in that environment and it served a purpose at that particular time and helped us to think about how we carry on and give safe care in the really, really difficult place that we were all working.

And that brings me to the point about MDT working. It was fantastic. Every morning, at nine o’clock on the ward, we would have a huddle and every single discipline was there to actually be involved in everything that we needed to do that day with the patients.

For me, the shining stars were the physios and the occupational therapists (OTs). They were so good at trying to get people on their feet. Anybody who had been in critical care and had been ventilated, they’d lost so much of their muscle tone, health, you name it. And the physios and the OTs got them back on their feet and got them home again and it really did shine a light on how great our MDT colleagues are.

Dr Chadwick: We had loads of colleagues, like our vascular surgeons, who came and said, ‘we’re here to help’. The way our respiratory MDT started setting up was that we gave them a physio to lead them as a proning team. There’s this wonderful image of Annika who’s an amazing physio and quite a petite lady, and these six quite bulky vascular surgeons turning this patient. But they learned very quickly that the rules were you just do what Anika says to the letter. It was serious because you’re turning someone on a ventilator – you can really muck it up – but it was really wonderful to watch.

Exactly as you describe, Phyllis, it was fabulous MDT working. And that’s actually stayed with us in Oxford: to this day: we do a lot more proning and our physios still run our proning teams, not our doctors. We’ve decided that they do a better job, and therefore that’s very much left with them. Whoever’s there doing the proning, be that a consultant or whoever it is, that doesn’t matter as in that moment, the physio is in charge. We listen to them, we do what we’re told and we prone very safely.

I think acute respiratory failure is just a lovely example of a bit of medicine where the MDT does make it all work. If you took any one cog away, all of it falls away.