COVID-19 AND THE ROLE OF OXYGEN IN PALLIATIVE CARE AT HOME
Dr Lyn Jenkins, edited by Ruth Waterman
There is good evidence that high-flow oxygen in hospital would improve my chances of survival but what about home-delivered oxygen? Does low-flow oxygen through a mask or nasal tubes, or a positive pressure ventilation machine (such as that which relieves breathing problems during sleep), make a difference to survival? I’ve not come across any case studies or random control trials of Covid care at home from any of the countries who were ahead of us as the pandemic developed. In countries with limited access to hospital care this will become an important issue.
And if I were to stay at home, would home-delivered oxygen help to make me more comfortable, even if it would not affect my survival chances? Which symptoms am I hoping it could control? Breathlessness certainly; but also confusion, delirium, anxiety?
Although various agencies have produced guidance about end of life care for Covid-19, some do not mention oxygen, some mention it in passing, and some say oxygen is not very helpful. It may be that high-flow oxygen in hospital relieves symptoms whereas low-flow oxygen at home doesn’t. If so, and if opiates are not sufficient on their own, then staying at home would deprive me of a comfortable death. If, on the other hand, it turns out that oxygen makes little difference to symptom relief, or that home-delivered oxygen is just as good and easily available, or that opiates are equally or more effective, then I could make the decision to stay in my own bed, confident that I won’t be risking putting myself and my loved ones through a distressing death by staying at home – at least as far as oxygen is concerned.
Since confusion and delirium may be exacerbated by low oxygen saturation, what sort of oxygen therapy is likely to help? Are alternatives such as haloperidol just as effective, and could they be administered easily at home? Anxiety and panic are probably secondary reactions to symptoms such as breathlessness, so they might well respond to oxygen indirectly; conversely, an increase in carbon dioxide levels as a result of oxygen therapy may actually induce panic. More questions to be answered before coming to an informed decision.
Finally, I ask myself, should I buy a pulse oximeter so that I can monitor my oxygen saturation? Would that help to make me comfortable, or only increase my anxiety if there is no access to oxygen, or if the flow-rate and delivery of the oxygen available is not effective in raising my blood oxygen level?
A recent rapid review on the CEBM Covid-19 Evidence Service seeks to answer some of these questions. Perhaps unsurprisingly, they found no evidence relating directly to Covid-19, although three reviews are underway. Looking at related studies of oxygen supplementation at end of life in conditions such as heart failure and chronic obstructive pulmonary disease, two results stand out: (i) there is no palliative benefit if the oxygen saturation is normal in the presence of breathlessness, and (ii) very near the predicted end of life, the paraphernalia of oxygen delivery becomes obtrusive, and opiates are preferable. The review also considers the currently available UK guidelines and finds that they are not concordant on the use of oxygen. No doubt, in the light of experience, they will become more so.
My conclusion is that I am not likely to find the evidence I need in order to make a considered decision until the experience with oxygen at home is investigated, and we have the benefit of case studies. Evidence comparing different flow levels and forms of ventilation is vital and I look forward to future updates from the rapid review team. We may get further data from reports about palliative care for Covid-19 in low-income countries, where access to low-flow oxygen, without ventilation, will often be the only option.
As things stand, having oxygen at home is not a prerequisite for me personally, although I would prefer to have it available. To date, my GP has been unable to reassure me that any form of rapid palliative support would be available in my area, and until that is in place I would not risk staying at home. I’ve decided to buy a pulse oximeter as a way of identifying the right moment to seek help. But were I to be in a position where I was using oxygen at home and my condition was deteriorating, there would probably come a point when the oximeter would no longer be helpful for decision-making and would merely increase my anxiety.
There still remains an elephant in the room – where would the oxygen come from? Rumour has it that the British Oxygen Company has diverted their community supplies of oxygen to the hospitals. Even if it were available for community use, could my health team have urgent access to it? And a baby elephant – if using positive pressure devices is beneficial, either for life extension or palliation, where would they come from?
If I find any answers, I’ll update this blog. If you find answers, please let me know. In the meantime, keep breathing – with or without supplementary oxygen!