Intubate, Ventilate, Prone, Repeat…
25th January 2021
UK COVID Deaths – Daily 592 / 7-Day average 1239
Total UK COVID Deaths within 28 days – 98,531
Total UK Deaths with COVID-19 on the death certificate – 95,829 (up to 8th Jan)
James Cook Hospital – Total COVID deaths – 477
All COVID cases within South Tees Hospitals Trust – 238
James Cook Critical Care
COVID cases – 39 (22 ventilated)
Non-COVID cases – 30 (13 ventilated)
Things remain just as busy as they were last week. We continue to look after a large number of very sick COVID patients. It has become difficult to keep track of all of them, spread out as they are over a number of separate Intensive Care Units and CPAP bays on the wards. They also are of a similar age, have similar stories, similar blood tests, similar chest X-rays and similar problems. The way we treat each patient is the same and, at times, this can be very repetitive.
Keeping up to date with everything that is happening can be tricky. During the first wave we had far fewer patients and we managed to keep tabs on the progress of each and every one - mostly. We are still attempting to do this but it is proving much harder. We are taking an awful long time to hand over each and every patient. I’m not sure this is very efficient; spending an hour talking about a group of patients that you don’t know and who you will not be looking after is perhaps not the best use of our time. This doesn’t seem to stop us trying and our handover meetings are becoming longer and longer. We are also not working in teams like we did during the first wave and this adds to the somewhat chaotic feel. Perhaps it’s just me. I really don’t have the world’s greatest attention span to be honest and I’m not known for concentrating on information that I deem unimportant. A good friend of mine is an eminent child-psychiatrist. He likes to tell me that I’m a fairly classic case of ‘burnt-out ADHD’.
When it comes to treating the patients, instead of just talking about them, we have by now, accumulated a huge amount of experience. We didn’t realise it at the time, but in some respects the first wave was something of a dummy run. We are now at the point where many of us can do this with our eyes closed which, given how tired we all are, is just as well.
However, every once in a while we see a patient who behaves differently from the others and who requires more attention. I saw one such patient today. The story was familiar – they were middle-aged and had presented to the hospital with COVID symptoms a few weeks ago. They had moved from receiving oxygen to CPAP to ventilation and then to prone ventilation within their first week. Initially, like so many other COVID patients, the aim was to optimise ventilation in order to allow adequate oxygenation. As we were doing this, our patient began to develop circulatory failure. This is not that unusual in a ventilated COVID patient but the situation continued to worsen. There were signs of heart failure and an echocardiogram (a scan using ultrasound waves to look at the heart) showed isolated right heart failure. Now, when people talk about heart failure they normally mean that the left side of the heart is not working. The left side of the heart (the left ventricle) is responsible for producing blood flow everywhere around the body with the exception of the lungs. The lungs are supplied by the right ventricle and we have seen a number of patients in which their COVID pneumonitis has led to the right ventricle failing in isolation.
COVID-19 causes damage to lung tissue and this causes less oxygen to be transferred to the blood vessels in the lung. The blood vessels sense that they are not receiving enough oxygen and their response is to constrict or narrow. This is useful in something like a regular pneumonia as blood flow is then diverted to more ‘normal’, unaffected areas of the lung. In COVID pneumonitis there are no normal areas of lung tissue left and so all the blood vessels in the lung constrict. This increases the resistance to blood flow and is called pulmonary hypertension. In severe cases this increase in pressure leads to failure of the right ventricle. This in turn results in less blood being delivered to the left ventricle and the total blood flow around the body decreases. This is not a good thing.
We have seen a number of such cases over the past 10 months and the development of pulmonary hypertension and right ventricular failure is not usually associated with a good prognosis. This is because it implies that the patient has particularly severe COVID pneumonitis. However, my patient’s heart failure seemed to be particularly bad. They were in shock and initially this had looked like circulatory failure from the widespread inflammation that COVID produces and septicaemia from a subsequent bacterial infection. Undoubtedly, both of these had played a part but the main problem appeared to be right ventricular failure secondary to pulmonary hypertension.
There is a drug called epoprostenol which can be used to dilate blood vessels. If you nebulise it into small droplets and add it to the ventilator tubing it will reach the blood vessels in the lung and dilate them. These are the same blood vessels which have been constricted by the lack of oxygen. We have used this drug in severely-ill, ventilated COVID patients before. It is thought that the drug enters the less-affected areas of the lung and dilates the blood vessels, leading to better blood flow and better oxygen uptake. Unfortunately, whilst it seems to make the numbers on the monitor better, it seems less likely to lead to any sustained improvement.
However, this was the first time we had tried it to primarily improve heart failure in a COVID patient whose main problem was not a lack of oxygen. The hope was that the pressure in the blood vessels would fall and the right ventricle would have less resistance to pump against. Blood flow should improve and so should the heart failure.
This is exactly what appeared to happen. It’s very satisfying when theory turns into practice and things work in the way you had hoped. The situation began to improve and by the time I left this evening things were looking better. Whether this improvement will continue is difficult to know. We had managed to buy our patient a bit more time and that’s often all we can do.