Welcome to issue 3 of The Plague Pit. On Thursday evening last week (26/3/20), 3 million people in the UK are said to have come out onto the streets and applauded NHS workers. If you were one of them, thank you.

Risky business

This issue is about the pandemic and some of the risks it poses to health care staff. A Guardian article last week reported that 39 Italian doctors had died with COVID-19. Yesterday morning brought news of the first UK doctor known to have died after testing positive – an ear nose and throat (ENT) surgeon. Various inaccurate stories had been swirling around since mid-March. Doctors get as much fake news as everyone else.

The position was eventually clarified in statement by Mark Watson, President of the British Laryngological Association – two on ICU, one of which improving. [1] Mr Watson observed that ENT and ophthalmological doctors in Wuhan were especially badly affected by COVID-19, because of their significant exposure to aerosolised secretions. From the 2003 SARS experience in Hong Kong, we know that healthcare staff are in particular danger early on, before a viral epidemic is recognised, when they may unwittingly expose themselves to infection without personal protective equipment (PPE) [2]

During the current pandemic, anaesthetists are usually the ones called on to intubate those COVID-positive patients who deteriorate sufficiently to require mechanical ventilation. Tracheal intubation is the anaesthetist’s ‘signature skill’ and it’s an aerosol-generating procedure (AGP). In the SARS epidemic, healthcare workers performing or exposed to tracheal intubation were six times more likely to contract SARS than their colleagues. [3]

My workmates are phlegmatic about the prospect of infection. Here’s a Whatsapp exchange between colleagues on the day the Prime Minister started isolating himself (27/3/20):  

“Anaesthetist 1: And now Matt Hancock. Dropping like flies. Who’s our Designated Survivor?

Anaesthetist 2: Lucky them….I’m dreading being admitted as a patient to Excel (horror emoji).

Anaesthetist 3: I quite fancied the o2! Great view from your bed!

Anaesthetist 1: Not when you’re prone.”

Friday at the office

At the end of the last issue of The Plague Pit, I was about to provide anaesthesia on a surgical list with an instruction from the Trust that ‘all patients are presumed COVID-positive’. At that time, Trust patients without COVID-19 symptoms were not routinely tested.  The ‘presume positive’ instruction was in place because asymptomatic individuals can still be carriers, capable of transmitting the infection to staff nearby.

As it turned out, my Friday morning patient was a ‘Don’t Know’ with an elbow fracture for fixation, the afternoon one was COVID-positive, for replacement of a broken hip. There are now many COVID-positive patients in the hospital but few have required surgery so far, so there was real anxiety among the staff in my theatre.

Our Trust has created laminated cards defining procedures that are AGPs –  and also cards displaying protocols for doing them. The protocols are intended to reduce the risk of aerosol exposure for staff. For a COVID intubation, the card says there should be three staff in full PPE – anaesthetist 1, anaesthetist 2 and an assistant – in the operating theatre, or ‘hot room’.

Here’s what it looks like in a drill we did earlier last week (see below). My colleagues are not wearing the fitted face masks they should be and the second anaesthetist, on the right, should have a visor on – but for the real event, these have always been available so far. Fitted masks, or ‘respirators’, are said to work better than standard fluid resistant face masks. ‘Anaesthetist 1’, in the middle of the picture, has been helping to organise the hospital supply of these fitted masks. She told me the numbers are 400 daily for the operating theatre, 2000 daily for the COVID critical care areas

All equipment the anaesthetist may need for a COVID intubation is set out in advance on a trolley in the hot room – it is all disposed of at the end of the surgery as contaminated, whether used or not. A fourth staff member in standard theatre scrubs waits in ‘cold room’ next door ready to open the door and hand in additional equipment or drugs. Usually induction of anaesthesia and intubation  needs just one anaesthetist and an assistant, so finding adequate manpower is now a constant challenge.

My first patent, Mr A, arrived from the ward on a bed, brought by a porter and a ward nurse in standard ward infection control gear. This means a paper gown with long sleeves worn over day clothes or scrubs, a plastic apron on top, a fluid resistant face mask and gloves – all disposable. Mr A came straight into the hot room, bypassing the anaesthetic room next-door, where induction of anaesthesia would usually take place. The aim of this is to limit potential contamination to a single room.

The COVID intubation protocol is very much more complex than a standard intubation to minimise the risk of secretions being blown out of the patient’s mouth. No staff other than the intubation team are permitted into the hot room during the induction or for twenty minutes after to reduce the risk of exposure to infected droplets.

This slows down operating lists enormously, as does the requirement that COVID-positive patients stay in the hot room for their immediate postoperative recovery period – usually half an hour at least. On waking, patients would normally go straight to a recovery ward so the theatre team can turn their attention immediately to the next patient on the operating list. Our recovery ward is unavailable now – it’s been converted into a COVID critical care unit. Even worse, nurses allocated to recover COVID-positive patients have to wait twenty minutes before entering the hot room after the endotracheal tube is removed (‘extubation’ – another AGP). More delays.

Elbow room

So on Friday, I was really pleased that both my patients were having surgery that can be conducted without a general anaesthetic. No general anaesthetic, no aerosol-generating intubation, less risk, faster throughput. Mr A, with his elbow, was suitable for a brachial plexus block.

In this technique, https//www.youtube.com/watch?v=Iega6O6IQM8) [5 minutes], a portable ultrasound scanner is used to identify the brachial plexus, the clump of nerves passing through the armpit on their way to innervate the upper limb. Local anaesthetic is then injected around the plexus. It’s the same principle as dental anaesthetic. Shortly after, the arm becomes immobile and insensate. The surgery is done with the patient awake or under light sedation.

I’m fond of the brachial plexus. It’s rather beautiful and it was the first bit of anatomy I ever learned. Back then, all first year medical students at my university had dissection sessions several times a week. We chose our student dissection partners within days of arrival, and two pairs of us were immediately allocated to each cadaver (left side, right side). My body was that of an elderly gentleman, rendered unrecognisable to anyone who knew him in life by the effects of the preservative. My dissection partner was a tall Indian lad who is my best friend. In the canteen on the first day, the fact that we had recently been face-to-face (or face to armpit) with a ‘real dead person’ gave us an entirely spurious status among our non-medical peers, temporary but not unwelcome.

It was evidently difficult and expensive for the university to look after twenty or thirty pickled corpses as they were serially mutilated over the course of the academic year. I think most medical schools now favour virtual over actual dissection – or, at the very least, demonstration over self-directed learning. Its hard to see how either could reproduce the misery of spending two hours poking around in an acrid chemical fug trying to find the dorsal scapular nerve. It’s about the thickness of a piece of cotton, as I recall.

I’ve been giving anaesthetics on a hand trauma operating list for many years. If patients on the list are fit, and I can see no particular advantage either way, I usually give them a free choice – general anaesthesia or brachial plexus block. For a variety of reasons, about 60% patients opt for a block. Some like the idea of a quicker recovery, some don’t like the idea of unconsciousness, some just feel it is less of a serious business than a GA.

On Friday, then, I told Mr A about the risks to staff posed by a general anaesthetic with intubation and he agreed to a block with sedation. It would clearly not have been his first choice. We were all very grateful and told him so.

Boy in the hood

Our second patient, Miss B, had broken her hip at home and then tested COVID-positive in the hospital. Once she came into the hot room, staff there definitely looked more nervous every time she coughed than they had with Mr A. She was suitable for a spinal anaesthetic, a technique where local anaesthetic solution is injected into the cerebrospinal fluid around the spinal cord using a needle in the lower back.

I’ll explain this technique some other time but, for the moment, it gives me an excuse to show some more PPE. My colleague pictured below is an expert on PPE and biological/chemical attacks. [5] He was keen to test some new equipment a couple of weeks ago and a patient having a spinal anaesthetic kindly agreed to allow him to treat her as COVID-positive for practice purposes

Over the top?

At the end of last week, I saw a couple of videos issued by the Armed Services in response to the #clapforourcarers campaign. They were really heartwarming, but frankly a bit embarrassing too. Healthcare staff are certainly taking more personal risk these days, but no-one is actually shooting at us.

It does all feel a bit military, though. Our TUBE team, who do the emergency intubations, have nice kit and a hint of fighter pilot swagger about them. Two of them are pictured above. They were visiting another colleague of ours, admitted with COVID pneumonia to one of our critical care units on Sunday. The caption under the picture is his own so we know he’s getting better, thank God. 

And there are special missions, too. The new Nightingale Hospital at London’s Excel is looking for volunteers. I was there before, pressing on someone’s chest as part of simulated cardiopulmonary resuscitation at the Big Bang Fair in 2013. I haven’t decided whether to sign up yet, but it would be strange to go back there as part of a real medical emergency.

The Good Soldier

[1] Statement by Mark Watson, 21/3/20. https://www.britishlaryngological.org/news/updated-and-amended-message-bla-president-mark-watson. Accessed 30/03/20.

[2] Gomersall CD et al. Transmission of SARS to healthcare workers. The experience of a Hong Kong ICU. Intensive Care Med 2006 Apr;32(4):564-9.

[3] Tran K et al. Aerosol generating procedures and risk of transmission of acute respiratory infections to healthcare workers: a systematic review. PLoS One. 2012;7(4):e35797. doi: 10.1371/journal.pone.0035797.

[4] MacIntyre CR, Chugtai AA. Facemasks for the prevention of infection in healthcare and community settings. BMJ. 2015 Apr 9;350:h694. doi: 10.1136/bmj.h694.

[5] Schumacher J et al. A randomised crossover simulation study comparing the impact of chemical, biological, radiological or nuclear substance personal protection equipment on the performance of advanced life support interventions. Anaesthesia. 2017 May;72(5):592-597.