RECOMMENDATIONS FOR THORACIC ANESTHESIA DURING THE COVID PANDEMIC

The following recommendations are based on the most current information provided by Shared Health in adherence to Manitoba Health and Public Health Agency of Canada guidelines and supported by consensus statements and guidelines published by different specialty and subspecialty societies.1-3

Our knowledge and understanding of the SARS-Cov-2 infection is evolving. There are many uncertainties and a definitive list of thoracic surgical procedures capable of generating infectious aerosols cannot be determined at this point due to limitations of available data.4-9 In situations where there is insufficient information or poor level of evidence, we took a precautionary stand, prioritizing the safety and protection of the healthcare team.

The same nomenclature adopted by Shared Health is used in this document:

Green Zone - COVID-19 Non-Suspect are patients who do not meet the criteria for testing and/or those deemed “recovered” by Public Health or by Infection Prevention and Control.

Orange Zone - COVID-19 Suspect are patients who have been tested and the result is pending OR those who, based on clinical symptoms or exposure history, need to be tested for COVID-19.

Red Zone - COVID-19 Positive are patients who have a positive test result and have not been deemed “recovered” by Public Health or by Infection Prevention and Control.

Enhanced Droplet and Contact Precautions (EDCP): N95 mask, gown, face shield and gloves.

Aerosol Generating Medical Procedures (AGMP): any procedure carried out on a patient that can induce the production of aerosols of various sizes, including droplet nuclei.

With regards to preoperative testing:

I- We recommend that ALL patients scheduled for ELECTIVE thoracic proceduresshould receive PCR testing for COVID-19 preoperatively, not only to guide PPEdecisions but mostly because of the high risk of morbidity and mortalityassociated with lung resections in asymptomatic or presymptomaticpatients.10-12

With regards to personal protective equipment (PPE):

I- Green Zone - COVID-19 Non-Suspect patients DO NOT require EDCP for AGMPif and only if:a. they had a negative swab in the last 24 hoursb. they have been hospitalized for at least 14 days and have no symptoms

that have prompted testing for COVID-19

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20

c. they have been hospitalized for at least 14 days, they have developedsymptoms that have prompted testing for COVID-19 AND the test result isnegative

II- AGMPs routinely performed during thoracic anesthesia and common to othersubspecialties include bag-mask ventilation, intubation, extubation and deepsuctioning of endotracheal tube. Recommendations about adequate PPE andbest practices to avoid risk of infection during these procedures have beenmade elsewhere.

III- There is currently controversial and insufficient data to create acomprehensive and definite list of thoracic procedures capable of generatinginfectious aerosols.4-8 The following is a suggestion based on limited evidenceand consensus amongst the thoracic surgical and anesthetic team, andcorroborates with practices being adopted across the country. Thoracicprocedures considered to be AGMP include:1. Diagnostic bronchoscopy (with washings and bronchoalveolar lavage)2. Tracheostomy3. Tracheal resection4. Rigid bronchoscopy5. Dilatation of subglottic stenosis6. Lung decortication7. POEM (Per Oral Endoscopic surgery) for Zenker’s diverticulum

* EDCP should be used at all times during AGMPs for:Orange Zone - COVID-19 SuspectRed Zone - COVID-19 PositiveGreen Zone - COVID-19 Non-Suspect who has been tested, has received a negativeresult but the AGMP is occurring more than 24 hours from when the swab/sample wastaken OR who has been in hospital less than 14 days and has not been tested

IV- Medical procedures performed in the thoracic operating room considered atrisk for aerosol generation:1. Sleeve lobectomy2. Bronchoplasty3. Pericardial window (due to risk of lung injury)4. Lung isolation and One-lung ventilation (OLV)

* EDCP should be used at all times during procedures at risk for aerosol generationfor:Orange Zone - COVID-19 Suspect

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20

Red Zone - COVID-19 Positive Green Zone - COVID-19 Non-Suspect who has been tested, has received a negative result but the AGMP is occurring more than 24 hours from when the swab/sample was taken OR who has been in hospital less than 14 days and has not been tested

With regards to air clearance time:

I- Operating rooms are considered to have 20 air changes per hour (20 ACH). Ittakes 14 minutes for 99% air clearance after an AGMP. OR doors must remainclosed at all times while an AGMP is performed, and remain closed for 15minutes after the last AGMP was performed.

With regards to lung isolation:

I- There is a small, theoretical risk of environmental contamination during OLVwhich derives from continuous manipulation of the operative lung, possible airleaks from endotracheal tube malposition or dislodgement during surgery, andcircuit disconnection which can be accidental or necessary for bronchoscopiesand repositioning of the double-lumen tube (DLT) or bronchial blocker (BB)once surgery is underway. Deep endotracheal suctioning is frequentlynecessary before lung re-expansion, in patients with lung infections,hemoptysis and hyperreactive airways. In-line suctioning can be used throughthe tracheal lumen of a DLT, but the catheters may not be long enough to beused through the bronchial lumen depending on which size of DLT is chosen.For these reasons, we recommend that appropriate PPE should be used duringlung isolation and one-lung ventilation as mentioned above.1-3

II- We suggest preference should be given to the use of DLT for lung isolationbecause 1) it is the device most providers are familiar with; 2) repositioningduring surgery is less often required; 3) it allows access to the non-dependentlung for bronchoscopy, suction or continuous positive airway pressure (CPAP)if necessary; 4) it can be placed without bronchoscopy if necessary.

III- The DLT position should be checked immediately after intubation. Ensureapnea and absence of flow. Confirm adequate placement with the TowerVideo Bronchoscope or a Disposable Flexible Bronchoscope. Avoid using theeyepiece to maintain safe distance from the airway during bronchoscopy.Positive pressure ventilation should be initiated once position is confirmed,circuit is connected and cuffs are inflated.3,13

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20

IV- The dirty bronchoscope poses a significant risk for contamination and cross-infection. Make sure to keep it in a designated area during the case. (ie: Mayostand or plastic container).1-3,13

V- Reconfirm the position of the DLT in the lateral position following these steps:1) stop ventilation and open APL valve to release positive pressure from thecircuit; 2) clamp the surgical lumen and correspondent angle piece beforedisconnection; 3) apply another N100 filter to surgical lumen and then releasethe correspondent clamp – non-dependent lung deflation and any aerosolgenerated from lung manipulation will then be vented through this filter.(Figure 1)

Figure 1 - DLT with N100 filter on lumen of operative lung

VI- If bronchoscopy or repositioning of the DLT is necessary during the case, makesure to stop ventilation, open the APL and allow lung deflation before removingthe N100 filter from the surgical lumen or disconnecting the circuit.

VII- If CPAP is necessary no manage hypoxia during OLV, the device can be appliedto the N100 filter as shown in Figure 2.

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20

Figure 2 - CPAP applied to no non-dependent lung. (Adapted from: Thornton M, Reid D, Shelley B, Steven M. Management of the airway and lung isolation for thoracic surgery during the COVID-19 pandemic:Recommendations for clinical practice endorsed by the Association for Cardiothoracic Anaesthesia andCritical Care and the Society for Cardiothoracic Surgery in Great Britain and Ireland. Anaesthesia.2020;75(11):1509-1516)

VIII- In patients who are already intubated, it is reasonable to use a bronchialblocker instead of attempting to exchange the single lumen tube for a DLT, tominimize AGMPs and complications from airway management. The same stepsdescribed above should be used while performing bronchoscopy to positionthe BB. To avoid aerosolization through the BB, an N100 filter can be connectedusing the 15 mm adapter provided in the package (as shown in Figure 3). As analternative, the BB can also remain occluded as there is evidence that adequatelung deflation can be achieved without opening the device to theatmosphere.14

Figure 3 - The 15 mm adapter (a) provided with bronchial blockers used to connect N100 filter to the Arndt bronchial blocker (b) and the EZ-blocker (c).

IX- Ensure adequate neuromuscular blockade at all times when manipulating theDLT and no positive pressure ventilation should occur unless the circuit isclosed.

X- Minimize testing for lung leaks or bronchial staple line leaks. Encourage visualinspection by the surgical team.

a) b) c)

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20

XI- Ensure slow, low pressure gradual expansion of the lung at the end of theprocedure to avoid aerosol generation.

XII- With a large air leak, there is a potential to aerosolize through the chest tubesystem suction port. Consider a filter on the chest tube suction port.

XIII- GOOD COMMUNICATION BETWEEN SURGERY AND ANESTHESIA IS ESSENTIALTO MINIMIZE AEROSOL GENERATION DURING THE PROCEDURE

References:

1. Şentürk M, El Tahan MR, Szegedi LL, et al. Thoracic anesthesia of patients with suspectedor confirmed 2019 novel coronavirus infection: preliminary recommendations for airwaymanagement by the European Association of Cardiothoracic Anaesthesiology ThoracicSubspecialty Committee. J Cardiothorac Vasc Anesth. 2020; 34:2315.

2. Shaylor R, Verenkin V, Matot I. Anesthesia for patients undergoing anesthesia for electivethoracic surgery during the COVID-19 pandemic: A consensus statement from the IsraeliSociety of Anesthesiologists. J Cardiothorac Vasc Anesth. 2020;21:S1053-0770(20)30722-9. Online ahead of print.

3. Thornton M, Reid D, Shelley B, Steven M. Management of the airway and lung isolation forthoracic surgery during the COVID-19 pandemic: Recommendations for clinical practiceendorsed by the Association for Cardiothoracic Anaesthesia and Critical Care and theSociety for Cardiothoracic Surgery in Great Britain and Ireland. Anaesthesia.2020;75(11):1509-1516.

4. Tran K, Cimon K, Severn M, Pessoa-Silva CL, Conly J. Aerosol generating procedures andrisk of transmission of acute respiratory infections to healthcare workers: a systematicreview. PLoS One. 2012;7(4):e35797.

5. Pasnick S, Carlos WG, Dela Cruz CS, Gross JE, Garrison G, Jamil S. SARS-CoV-2 Transmissionand the risk of aerosol-generating procedures. Am J Respir Crit Care Med.2020;202(4):P13-P14.

6. Lynch JB, Davitkov P, Anderson DJ, Bhimraj A, Cheng VC, Guzman-Cottrill J, Dhindsa J,Duggal A, Jain MK, Lee GM, Liang SY, McGeer A, Lavergne V, Murad MH, Mustafa RA,Morgan RL, Falck-Ytter Y, Sultan S. Infectious Diseases Society of America Guidelines oninfection prevention for health care personnel caring for patients with suspected or knownCOVID-19. Clin Infect Dis. 2020;27:ciaa1063. Epub ahead of print.

7. Harding H, Broom A, Broom J. Aerosol-generating procedures and infective risk tohealthcare workers from SARS-CoV-2: the limits of the evidence. J Hosp Infect.2020;105(4):717-725.

8. Howard BE. High-risk aerosol-generating procedures in COVID-19: respiratory protectiveequipment considerations. Otolaryngol Head Neck Surg. 2020;163(1):98-103.

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20

9. https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-recommendations 10. Cai Y, Hao Z, Gao Y, Ping W, Wang Q, Peng S, Zhao B, Sun W, Zhu M, Li K, Han Y, Kuang D,

Chu Q, Fu X, Zhang N. Coronavirus Disease 2019 in the perioperative period of lung resection: a brief report from a single thoracic surgery department in Wuhan, People's Republic of China. J Thorac Oncol. 2020;15(6):1065-1072.

11. Salmerón Jiménez M, Hermoso Alarza F, Martínez Serna I, Marrón Fernández C, Meneses

Pardo JC, García Salcedo JA, Torres Serna A, Manama Gama MG, Colmenares Mendoza OE, Diaz-Hellín Gude V, Gamez García AP. Clinical features and outcomes of thoracic surgery patients during the COVID-19 pandemic. Eur J Cardiothorac Surg. 2020;58(4):738-744.

12. Sathiamurthy N, Balasubbiah N, Dharmaraj B. Aerosol-generating procedures in thoracic surgery in the COVID-19 era in Malaysia. Asian Cardiovascular & Thoracic Annals. 2020:28(8) 495–499.

13. Tryphonopoulos P, McFaul C, Gagne S, et al. COVID-19 and One-Lung Ventilation. Anesth

Analg. 2020; 131(2):e90.

14. Bussières JS, Somma J, Del Castillo JL, et al. Bronchial blocker versus left double-lumen endotracheal tube in video-assisted thoracoscopic surgery: a randomized-con- trolled trial examining time and quality of lung deflation. Can J Anaesth. 2016;63:818–827.

Department of Anesthesiology, Perioperative & Pain Medicine, WRHA Anesthesia Program Anesthesia – Shared Health MB 25-Nov-20