I’m concerned to see a growing lack of common sense in the care of elective surgical patients during the COVID-19 pandemic. This lack of common sense in the time of COVID endangers the healthcare providers caring for patients. It can also put patients at risk. I remind my OR nurses to put on gloves when they help with intubation. My team may surround the bed, chatting happily about weekend plans while my airway management sprays aerosols. The cleaning crew will occasionally start disinfecting floors before the patent is extubated.
Should we be concerned? Yes! This article will alert you to some easily preventable risks.
Infection Rate Among Health Care Workers
Proper protocol and Personal Protective Equipment (PPE) can protect health care workers, but they are not perfect. During the initial 2003 SARS epidemic, a systematic review showed increased risk of SARS infection among those who performed aerosol generating airway procedures compared to those who did not. Nine percent of interviewed healthcare workers who had intubated SARS patients developed SARS. [1]
The OR, or Odds Ratio, of provider infection at that time were:
- Intubation: 6.6
- Tracheotomy: 4.2
- Non-invasive ventilation: 3.1
- Manual Ventilation Before Intubation: 2.8.
An odds ratio of 6.6 means that someone performing intubation was 6.6 times as likely to get SARS than someone who was not.
In addition to dealing with yet another new virus, the current SARS-CoV-2 pandemic has been plagued by shortages of PPE, supplies, equipment, and trained staff. The Director of the Pan American Health Organization (PAHO) reported in September 2020 that in the Americas at that time, 570,000 health workers had been infected with COVID-19 and that 2,500 had died. As of November, 230,000 US health care workers had been reported infected and 822 had died.
One study followed 1,718 healthcare workers performing airway management on COVID-19 patients in 503 hospitals in 17 countries. A reported 10.7% of providers involved with intubation in that study developed either symptoms or a positive COVID-19 test that That’s one in ten. [2]
We are at risk if we manage the airway of a COVID positive patient. Wear your PPE. Use it correctly. Wash your hands. Socially distance (even in the lunch room and locker room). Be smart.
Care of The Known COVID Positive Patient
If we know a patient is COVID positive, then we all approach airway management with respect and — to be honest — some fear. Safety precautions protect the intubator and her/his team from direct contact and from aerosols generated by the procedures. [3]
Getting dressed to intubate a COVID-19 patient reminds me of medieval knights being dressed by their pages for the battlefield. Nurses and respiratory techs help us don long sleeved, waterproof gowns, eye protection, N95masks and PAPRs with hoods, one or two layers of gloves, and waterproof booties. We’re surrounded by helpers who hand us instruments and who immediately take them back once used — ensuring those now soiled instruments don’t contaminate other surfaces or infect other people.
With the known COVID patient, everyone is watching everyone else’s back for possible cross contamination. That is not always happening when treating the elective surgery patient. We need to use common sense in the time of COVID.
Assume All Patients Are Potentially Infectious
Initially, we approached intubation for elective cases with many of the same precautions because intubation and ventilation generate aerosols. However, with time that fear factor during elective cases has definitely eroded. I am not suggesting everyone needs to use a PAPR for every intubation. I am suggesting that you need to use COVID common sense.
Asymptomatic and Pre-Symptomatic Patients
You cannot look at an elective surgical patient, or indeed any asymptomatic person, and know who is infected with SARS-CoV-2 and who isn’t. Just the other day my surgicenter cancelled one of my elective surgery patients. He was an asymptomatic, healthy 30-year-old who tested COVID positive in admitting. About 80% of patients with COVID-19 eventually develop symptoms. But that means about 20% who are infected and infectious, remain symptom free throughout their “illness” [4,5]. It also means a significant number are pre-symptomatic. These patients can easily arrive for elective outpatient surgery .
False Negative COVID Tests
Despite the fact that most patients arrive to my workplace with negative COVID tests, some percentage of them can still be infected — and infectious. Tests that are up to 96 hours old may miss the window of positivity. The reported rate of false negatives from antibody tests is usually quoted as 20%, but the range of false negatives is from 0% to 30% depending on the study, the type of test, and when in the course of infection the test is performed.
Decide Where To Put The Patient’s Opaque Face Mask
Let’s start with one easily addressed and easily overlooked risk. All patients enter the OR wearing some form of opaque face mask. This sounds silly, but decide where to put the patient’s own opaque mask. The patient’s mask is a grossly contaminated piece of PPE. Some masks are just disposable surgical masks. Some are reusable personalized cloth masks with sentimental value that you don’t want to lose. Putting the mask in a plastic bag is a perfect solution to minimize cross contamination and prevent people and equipment from touching it.
Think About Aerosols In Your Environment
Following the initial SARS epidemic, there were studies examining how aerosols spread during airway management. Coughing and manual ventilation produce more aerosols than intubation and extubation themselves. Volitional coughing produces a peak concentration of 1688 particles/L and an average of 134 particles within 12 seconds at a distance 0.5 m from the subjects mouth. Intubation and extubation at the same distance produces 1.4 and 21 particles/L, and averages of 7 and 100 total particles within 5 minutes. Dispersion of aerosols is greatest with unprotected forceful coughing and least with either weak coughing or coughing through an endotracheal tube. [6,7]
Mask ventilation also produces more aerosols than does intubation or extubation. As you might imagine, aerosol spread is greater when a less experienced provider is using the bag-valve-mask device instead of the experienced provider. This no doubt relates to ability to obtain a good mask fit with a tight seal.
Continuous suctioning (performed throughout the procedure in question) vs. intermittent suctioning diminished aerosols in all tests during aerosol producing procedures. [7]
Avoid the Need for Ventilation
If it’s safe for the patient, avoid manual ventilation before and during placement of either an endotracheal tube or an LMA. Avoiding ventilation minimizes the risk of aerosol spread. This requires preparation.
Pre-Oxygenate Your Patient Well
Preoxygenation prevents and/or postpones the onset of hypoxia while the patient is apneic during intubation. Preoxygenation becomes especially important if the intubation attempt becomes difficult and prolonged.
Use head straps to hold the mask to form a good seal on your patient’s face. In the absence of head straps have your assistant (wearing gloves) hold the mask. Have the patient take deep breaths. A discussion of pre-oxygenation and how to use it safely prolong the period of apnea before intubation is here:
“Preoxygenation Can More Than Double Time To Hypoxia During Apnea”
If oxygen saturation drops during a prolonged attempt then by all means ventilate the patient using a good mask seal. Patient safety comes first.
Examine The Airway!
The unexpectedly difficult airway can occur at any time. Management of a difficult airway can definitely cause direct contamination and generate aerosols. It is too easy to miss warning signs when the patient wears a mask during the interview. Even with COVID, common sense requires looking at the patient.
The pandemic has made people afraid to do physical exams. Take the time to examine your patient’s airway in the preoperative area. Take the patient’s mask off, examine the airway with your usual thoroughness, have them put the mask back on. Touch the patient as needed, then wash your hands. for a review article on predicting and managing difficult airways read here:
10 Rules For Approaching Difficult Intubation: Always Prepare For Failure
Consider Video-Laryngoscopy
Difficult intubation forces ventilation and generates aerosols. Consider using video-laryngoscopy if you have it. If you’re like me, most of the locations where I work have limited video-laryngoscope capability. One of the surgicenters has one GlideScope blade and it must be cleaned between uses. This means that if you see signs of difficult intubation, and think you will need the video scope, you must to coordinate with your partners ahead of time. If you just want it on standby, leave it outside the room so it doesn’t get contaminated.
Always have different standard laryngoscopy blades and another intubation aide like a bougie available in the room. Delay in obtaining equipment puts patients at risk and spreads more aerosols.
Continuous Suction
Use of continuous suction during intubation, extubation, and mask ventilation is an easy technique to reduce aerosol risk. Have your nurse hold the suction catheter. [7]
Ventilate Using Good Technique
When you do ventilate, ensure a good mask seal. Manual ventilation generates more aerosols than intubation itself, especially if the mask seal is poor. Don’t hesitate to ask your nurse to assist you. The nurse can improve seal at the side of the mask, or squeeze the bag while you seal the mask with both hands. Don’t wait until you need your nurse’s help before you teach them how to best help you. As mentioned above, continuous suction can decrease aerosol spread.
To read about how to obtain a good mask fit for ventilation and about double handed ventilation read here:
Mask Ventilation: Avoiding Hand Fatigue
Don’t Contaminate Yourself or Your Space
The process of intubation consists of touching the patient’s mouth to open the airway, placing the endotracheal tube (ETT), removing the laryngoscope and putting it down, grasping the ETT where it exits the patient’s mouth while you verify placement, squeezing the bag to ventilate the patient, picking up the roll of tape to secure the tube. COVID common sense dictates that you think of all the opportunities to directly contaminate your hands, your equipment, and your workspace.
Consider Double Gloving
Consider double gloving if you have adequate access to PPE. Double gloving allows you to intubate the patient and then to discard the first layer of gloves after you put down the laryngoscope and before you squeeze the bag. In the event of an esophageal intubation, you still have a pair of gloves on to reintubate.
Gloves have occasionally been in short supply. If you can’t double glove, be mindful about which surfaces you touch and consider wiping them clean soon after intubation.
Create A Place For Soiled Instruments And Removed Devices
If you put your soiled laryngoscope blade down on your anesthesia machine or anesthesia table, you will directly contaminate all of those surfaces. When you take your gloves off and touch those surfaces, you will then spread that contamination further. Things I have used to corral those germs include zip lock bags, small plastic trash bags, the blister packs that the laryngoscope came in from central supply, as well as just laying them in an emesis basin isolated from everything else. You don’t need an expensive solution. You just need to be consistent so your staff knows where to put things when they’re helping you.
Have your trash basket close so that you can then quickly throw away the endotracheal tube or oral airway. I personally am never going to win a basketball contest pitching those things into a trash basket 4 feet away.
Clean The Instruments Between Cases
Obviously surgical instruments automatically get cleaned between cases. However, does your environmental services crew know what’s clean and not clean on your workspace. If I have wrapped my laryngoscope back up in its original blisterpack to keep it from contaminating my tabletop, then maybe they don’t. Good communication is important.
Extubation: Manage Coughing
Extubation can spread aerosols. In my unproven opinion, the biggest risk from extubation is the patient vigorously coughing after the device is removed. As observed above, coughing generates more aerosols than most airway procedures. Here are some of my thoughts to minimize exposing my team to aerosols during the critical time of extubation.
Control Which Staff is Nearby
You need your nurse immediately available in case of problems, but not necessarily right next to the airway. People helping you should have gloves, a mask, and eye protection. Have unneeded people stand back or perhaps leave the room. I call out to alert people to shield their face and eyes right before I pull the tube.
Choice of Endotracheal Tubes vs Laryngeal Mask Airway
In my experience, patients tend to cough more after endotracheal intubation vs. an LMA. Since COVID, I have witnessed a trend toward using more LMAs for cases where intubation was previously more common. There is nothing wrong with using an LMA if this makes safe sense for your patient’s surgery. I will use an LMA for cases like hip replacement or shoulder rotator cuff repair if the patient:
- will be in a position that I can manage that airway if the LMA dislodges
- will be at low risk for hypotension, bleeding, or other complication during the procedure
- is not having surgery which would be sabotaged by a dislodged LMA.
For example, I will consider an LMA in a patient for rotator cuff repair who will be positioned on the side. I will not use an LMA for that same patient who will be sitting upright in the Captain’s Chair with their head in a fixed support brace and a foam face shield. I use common sense to choose on a case-by-case basis based on risk assessment, not COVID.
Consider Extubating Deep
By extubating deep, you can often avoid the stimulus to cough. However, this must be done with preparation and forethought to avoid laryngospasm. I make sure my patient is breathing spontaneously with an adequate tidal volume and rate. If I have lightened the anesthetic with a plan to expedite wakeup and turnover, I will make sure that the patient is deep enough to tolerate the stimulus of removing the airway. Consider continuous suction during tube removal.
You must always be prepared for complications. For a review article on how to decrease the risk of airway complications, read here:
Boredom Interrupted: 10 Causes of Airway Complications and How to Avoid Them
Cover The Patient’s Face Immediately
I have the ventilation mask within easy reach so that I can immediately cover the airway. I always did this pre-COVID to ensure the patient was not in laryngospasm and was breathing adequately. Now I am also doing it to shield my team from aerosols generated by any coughing that might occur.
Cover Patient Face for Transport
The patient’s face should be covered with a mask for transport. If the patient is awake and stable, then I feel very comfortable using the patient’s original opaque mask.
However, if the patient is sleepy, then I use the typical clear Hudson mask rather than put the patient’s own opaque mask over their face. I had a close call when a sleepy patient passively regurgitated a large amount of thick, particulate matter under their opaque mask. Fortunately, I heard the burp, checked immediately, and was able to avoid any aspiration. But that near miss scared me. The clear Hudson mask lets me see the airway and verify that the patient is breathing. If the patient coughs it is contained.
To avoid blowing aerosols throughout the hallway on the way to PACU, I do not always connect oxygen for the trip. If the patient is breathing adequately and the oxygen saturation is good, then I feel the patient is perfectly safe during the short transit. I, of course, watch them carefully. If the patient needs oxygen, then I use the lowest flow appropriate.
Cleaning the OR
Let me just finish by saying that it makes no sense to start cleaning the OR before the patient is out of the room. One cough and the newly cleaned surface is contaminated.
Use Common Sense With COVID
The SARS-CoV-2 pandemic has had a profound impact on how we are practicing anesthesia. We all know what to do if the patient is COVID positive. We equally have use common sense to protect our team from the elective surgical patient who, unbeknownst to us, may also be COVID positive. And we need to do so in a way that maintains patient safety.
May the Force Be With You!
Christine Whitten MD
Author Anyone Can Intubate: A Step By Step Guide
And
Pediatric Airway Management: A Step By Step Guide
During the pandemic, Dr. Whitten’s books are available on amazon.com at cost.
References
- Meng L, et.al. Intubation and Ventilation Amid the COVID-19 Outbreak: Wuhan’s Experience. Anesthesiology 2020.
- El-Bohgdadly K, et. al. Risks to healthcare workers following tracheal intubation of patients with COVID‐19: a prospective international multicentre cohort study. Anaesthesia 2020 Jun 6; https://doi.org/10.1111/anae.15170
- Luo M, Cao S, Wei L, et al. Precautions for Intubating Patients with COVID-19. Anesthesiology. 2020;132(6):1616-1618. doi:10.1097/ALN.0000000000003288
- Shmerling, R (2020, August) Which test is best for COVID? Retrieved from URL: https://www.health.harvard.edu/blog/which-test-is-best-for-covid-19-2020081020734#:~:text=False%20negatives%20—%20that%20is,%20high%20as%2037%25
- He J, Guo Y, Mao R, Zhang J. Proportion of asymptomatic coronavirus disease 2019: A systematic review and meta-analysis [published online ahead of print, 2020 Jul 21]. J Med Virol. 2020;10.1002/jmv.26326. doi:10.1002/jmv.26326
- Brown J. et. Al. A quantitative evaluation of aerosol generation during tracheal intubation and extubation. Anaesthesia 2020 Oct 6; [e-pub] (https://doi.org.1111.anae. 15292)
- Chan, M.T., Chow, B.K., Lo, T. et al. Exhaled air dispersion during bag-mask ventilation and sputum suctioning – Implications for infection control. Sci Rep 8, 198 (2018). https://doi.org/10.1038/s41598-017-18614-1