COVID-19 / 코로나바이러스 발병: 기관지 검사를 수행하는 방법

The indication for bronchoscopy in COVID-19 patients has to be strictly defined and should only be performed in case of, for example, aspirations, atelectasis, or relocation of the airways–not routinely for diagnostic purposes.

Minimize the team to essential personnel only. Normally, this would consist of one examiner and two assistants. All required equipment should be prepared outside of the patient’s room. A single-use only bronchoscope and appropriate monitor should be utilized with infected patients.

Enter the patient’s room wearing personal protective equipment. This includes a FFP3 mask, protective glasses and visor, and doubled-up gloves. Gain consent from the patient by explaining the procedure being undertaken.

All vital signs are to be continuously and appropriately monitored. The ECG trace loudspeaker is to be switched on. The patient will be pre-oxygenated with an FI02 of 1.0. This should additionally be carried out in patients receiving extracorporeal membrane oxygenation therapy treatment.

The ventilator settings are now to be adapted. Generally, a volume-controlled ventilation mode with appropriate alarms and pressure limits is selected. The suction catheter is to be turned on and the fingertip piece closed.

The video bronchoscope monitor must be placed directly opposite and in front of the examiner. Bronchoscopy is carried out under aseptic or hygienic conditions. A pair of sterile gloves and a sterile gown are to be laid out. Under these exceptional circumstances, the sterile zone must be prepared directly on the anesthetized patient. Finally, all sterile equipment should be placed in the sterile zone.

The single-use bronchoscope will now be prepared for usage. This, in turn, is attached to the monitor by an assistant. The suction catheter is connected to the specimen collector and, in turn, to the bronchoscope’s suction port.

Finally, the system is tested. Three 20-milliliter lavage syringes are to be filled with 0.9 percent sodium chloride under sterile conditions and laid to the side. Immediately following, the patient will be put into a deeper anesthetic state, including neuromuscular blockade.

Before beginning the procedure, the team will follow a 10 second for 10 minute principle, whereby facts, procedural planning, potential complications, and team roles can be clarified, and outstanding questions can be answered. The procedure may begin once everything is clarified.

An assistant, whilst wearing two sets of gloves, positions the bite block. A side piece of the bite block is cut in order to prevent endotracheal tube dislocation. The first pair of gloves are then removed and disposed of. Anti-fog is sprayed on the bronchoscope tip and water-soluble lubricant over the bronchoscope insertion tube.

The ventilator function is paused in order to begin the bronchoscopy. This is clearly verbally communicated with the team. The closed suction system is detached and replaced with an adapted bronchoscope valve. The small cover flap of the adapted bronchoscope valve is now opened.

An assistant holds the endotracheal tube in orientation to the patient’s midline. This must be held for the entire procedure. The bronchoscope is inserted through the open adapted bronchoscope valve into the endotracheal tube.  Here, it is advanced further.

The endotracheal tube is flushed and is secretion mobilized and subsequently suctioned. The bronchoscope may now be advanced further following clearance of any secretion. Once the carina is visualized, orientation of the bronchoscope with respect to the tracheal cartilage can be achieved, as seen in this video. 

Here, we can see that the right lung has a buildup of secretion. This must be lavaged and suctioned before the lung can be further examined. Now, the passage is free. The carina can be viewed, and the right lung may be examined. We can orientate the bronchoscope image easily, once again, with respect to the anteriorly positioned tracheal cartilage.

Step by step, we examine the early branching right upper lobe, the right middle lobe, and the right lower lobe. The visual status of the mucous membrane, its vulnerability, any secretion, and/or bleeding must be assessed. The mucous membrane is often very fragile in COVID-19 patients. Pus is to be expected, especially in case of a superinfection of bacteria.

When required, a deep bronchoalveolar lavage may be carried out with 10 milliliters of 0.9% sodium chloride. A 30 seconds delay should be carried out prior to performing intermittent suction with short intervals until the specimen collector is filled with 10 milliliters of aspirate.

Here, this is performed in the right lung. Lavage to be separated by lung lobes and separate specimen collectors are respectively used. During the exchange of specimen collectors, it’s important to minimize any aerosolization of aspirate. The connectors are detached initially from the suction catheter, then the bronchoscope, and these are in turn connected to each other.

In COVID-19 patients, three rather than two specimen collectors should be acquired in order to aid diagnosis. The left lung will now be examined, beginning from the carina. The left lobes of the lung are also sequentially examined.

Here is the upper lobe, and finally, the lower lobe. Bronchoalveolar lavage is also carried out. To obtain specimens for cytology, a third lavage can be taken. Finally, the bronchoscope is to be reversed out of the left lung. At this point, as during the entire procedure, it is important to monitor the fragility of the mucous membranes through contact. This often occurs in viral infections, including COVID-19.

Now, the bronchoscope is reversed and the position of the endotracheal tube confirmed. The ventilator is paused in order to finish the bronchoscopy procedure. The bronchoscope is now removed from the endotracheal tube. The adapted bronchoscope valve is exchanged with a closed suction system. All connections in the ventilation circuit are to be checked.

Finally, the ventilator is switched on, and if necessary, the ventilator settings are adapted. The specimen collectors are now closed with a white top marked with laboratory stickers and placed in a marked bag to be sent, in turn, to virology and to microbiology. The single-use bronchoscope and all remaining materials are to be disposed of.

Thank you very much.