Welcome to The Plague Pit – issue number 2. By 09:00 on the morning of 25/03/20, 9,529 people in the UK had tested positive for COVID-19 and 463 COVID-positive people had died. [1]  

I arrived at work an hour before this, to attend a ward round in one of our Level 3 critical care wards. Level 3 involves the care of patients who require mechanical ventilation, or need support for two or more organs, e.g. drugs to support blood pressure and continuous dialysis for failing kidneys. Patients with positive COVID tests (‘COVID-positive’) with severe respiratory failure require Level 3 care. The critical care ward I went to has 15 beds and is a designated ‘’COVID-negative’ area. At the moment, the hospital is trying to separate COVID-positive critical care patients from those with negative tests. There were 9 patients there, all on ventilators, with ages ranging from 28 to 80 and  admitted with a fairly typical collection of diagnoses – surgical complications, sepsis, pneumonia and so on. All of them, as is common, had serious underlying medical conditions on top of their primary diagnosis.

On this occasion I was an observer. When not actually involved in patient care, my anaesthetic colleagues and I are now re-acquainting ourselves with the way critical care wards work and refreshing our clinical knowledge for even more COVID-positive patients. A ward round is a good way to do this.  Just before the round, though, I bumped into one of my anaesthetic workmates. He was going home to sleep, having been in the hospital on the 12 hour resident night shift – part of the emergency rotas introduced 48 hrs ago. He is on one of two ‘TUBE’ rotas – their role is to intubate known or suspected  COVID-positive patients as they deteriorate on different wards and departments around the hospital. Between the seven members of the team, each TUBE rota provides continuous cover. For each TUBE rota member, the week comprises a 12-hour night shift, a 12-hour day shift, an eight hour day shift and a 24 hour shift on call from home. It’s the same rota for the two teams of anaesthetists providing cover for patients who need surgical procedures in the operating theatres. Anaesthetists in the other three teams, deployed to act as critical care doctors in the new intensive care units, have a different timetable.  

For those on the TUBE night shift and others, there is insufficient overnight accommodation in the hospital. The Trust has negotiated rooms at a hotel nearby and doctors started staying there last weekend. Here’s a WhatsApp message a colleague sent me at the time:

“London is a ghost town looking out of my Top Floor Superking Suite in the totally empty hotel. No intubations so far today, 4 yesterday. It’s really freaky waiting for the carnage to begin tomorrow night, according to our modelling. Anyone know if I can hand in my resignation by Whatsapp?’ (21/3/20)”

Today I have been running training sessions for doctors from other departments. They want practice putting on (‘donning’) and removing (‘doffing’) personal protective equipment for when they conduct procedures on COVID-positive patients. Today’s customers are vascular surgeons who will shortly be allocated to critical care ‘line teams’. ‘Lines’ are thin plastic tubes that are inserted into blood vessels. In small veins, they allow intravenous fluid administration (‘drips’). In small arteries (‘arterial lines’), they allow doctors to monitor blood pressure continuously and take regular blood samples easily. In large veins in the neck or groin (‘central lines’) they are useful in several ways. Central lines help doctors assess the body’s fluid balance and heart function. They also allow doctors to give patients drugs that are necessary but too irritant to give by a smaller vein. One example is noradrenaline, commonly used to support blood pressure in critical care patients.

As the critical care patient numbers get really high in the next week or two, doctors here will be allocated to teams for specific tasks, as there will be so many of each task to do. I mentioned  ‘proning teams’ in the last issue. The vascular surgeons I’m teaching today operate on blood vessels, so know the anatomy of veins and arteries well – a good choice of specialist for the ‘line teams’. Ear, nose and throat surgeons will probably be deployed to make up ‘tracheostomy teams’. A tracheostomy is a surgical procedure that can be conducted in the critical care unit. Tracheostomy is also the word used to describe the hole the surgeon makes during a tracheostomy procedure. The skin incision for this is on the front of the neck, a little way below the Adam’s apple. The hole runs from the  skin backwards into the trachea. A tube can then be inserted through the hole into the trachea, and the outside end connected to  mechanical ventilator.

You can see a tracheostomy operation (4 min) here: https://www.youtube.com/watch?v=77Wi5Z3FOGk .

Tracheostomies are often performed on critical care patients to help ‘wean’ patents off ventilators, especially if they have been on a ventilator for more than a week. This is because a patient works less when breathing through a short tracheostomy tube than they do with a longer endotracheal tube. The theory is that resistance to laminar gas flow is lower – by the Hagen- Poseuille Law: (https://en.wikipedia.org/wiki/Hagen–Poiseuille_equation). We expect many COVID patients to require ventilation for more than seven days.

Today, I have also been teaching our Accident and Emergency colleagues how to intubate the trachea in COVID positive patients, using life-size mannikins. This is a complex business involving special COVID-specific procedures and equipment. Endotracheal intubation is necessary in most ordinary patients who require mechanical ventilation – and all COVID patients who do. It is an ‘aerosol generating procedure’, meaning that there are potentially lots of infected droplets released form the patient’s mouth. So there’s a high risk of COVID infection passing from patient to nearby staff through droplets. For various reasons relating to current resources for testing and the reliability of available tests, we often don’t know whether a patient is COVID-positive or not when we intubate them.

This means that anaesthetists are particularly interested in their personal protection equipment, which I’ll be writing about in the next issue. As it happens, I’ve just been told I am the anaesthetist tomorrow in a theatre where ‘all patients are assumed COVID positive’. Under our current COVID protocols, a general anaesthetic always means an endotracheal intubation. When I was training in the bad old days, doctors used to have a saying: ‘See one, do one, teach one’. For me and COVID-positive intubations, it’s evidently the wrong way round: ‘See one, teach one, and (in a few hours) do one’. I’ll let you know how I get on.

The Good Soldier

[1] Department of Health and Social Care and Public Health England. Number of coronavirus (COVID-19) cases and risk in the UK (25^th March 2020).

https://www.gov.uk/guidance/coronavirus-covid-19-information-for-the-public. Accessed 26/03/2020