Laboratory testing for known positive Ebola patients is different compared to testing for patients under investigation. We prefer that a dedicated laboratory be used for known positive Ebola for several reasons. There's greater control of the specimen disposition. There's less impact if, in the case of a spill. When there are spills in a main laboratory, we clean them up, and there's not really significant impact to the testing that goes on for all of the thousands of patients we test every day. However, if we had a spill in the main laboratory with a known positive Ebola sample, we would have to shut the laboratory down for a period of time until such period as we could get that spill contained and cleaned. There's also less angst amongst the staff. As you can imagine, for Ebola, there's a lot of anxiety produced about handling those known positive samples. Since we have a dedicated laboratory, we can contain that within a very select number of staff that can do the testing. And it allows us simpler waste management so that we don't have to sequester the Ebola samples separately from the main laboratory samples in a way that allows us to get rid of them without contaminating our normal waste stream. The serious communicable diseases unit laboratory is located within the unit. It's a short distance outside of the main portion where the patient care occurs. There is an anteroom between the patient rooms, and then our laboratory is just a few steps in front of that anteroom. It's quite small. We do most of our testing using equipment that is compact and self-contained. The staffing of our laboratory is critical. We use mostly our point of care staff and a few select staff from the main laboratory who work in this area. And there are some characteristics of those staff that are quite important. Many of the instruments we use fall under our our point of care section, and therefore, it made sense that we would use the same staff that are accustomed to that instrumentation to do the testing. All of the staff are trained and maintain their competencies on the equipment in the unit laboratory so that we can meet all of our regulatory requirements for the scope of testing that we perform. Once we have a patient in the unit, it becomes necessary to then transport specimens from the patient room to the laboratory. And while that may seem a simple characteristic, a simple approach, it isn't as simple as it seems. What we have to do is we collect the blood tubes just as we would in any nursing unit, in the patient room and label them according to our hospital protocols. They're then placed in a specimen bag which is closed and cleaned with a germicidal wipe. That bag is then put in a secondary specimen bag, which is also closed, cleaned with the germicidal wipe. That's handed through the door of the patient room into the anteroom of the unit to the nurse in the anteroom, who is holding a locking lid plastic specimen box. And that's then cleaned with a germicidal wipe before transport. That's handed from the anteroom nurse to one of our lab safety personnel outside of the, the laboratory and the anteroom, who then carries it to the testing area and hands it to the person in the laboratory who will actually perform the testing. Once the specimen bags are removed from that box, the whole process is reversed. And while that seems cumbersome and there are many steps to achieve, it really becomes necessary so that we can maintain the highest level of safety for our personnel. We do a, a limited test menu in the serious communicable diseases laboratory because that's really all that's necessary for these patients, who predominantly are receiving supportive care. The testing we provide utilizes blood gases, electrolytes so that we can monitor the fluid status of the patients, complete blood count so that we can see if they become anemic or have any hemorrhage, and a few limited other tests that are related. For instance, many of these patients are coming from Africa. And we need to be able to test for secondary infections, like malaria, that may affect people from the same region. We do have available to us in the laboratory the reverse transcription PCR for Ebola so we can monitor the blood for the presence of virus. We also very carefully monitor the electrolytes because it became apparent with all of our patients that fluid imbalance are critically important, and therefore, appropriate restoration of those electrolytes is essential to their care. We use blood gas monitoring to see the respiratory status of those patients so we can know that they're oxygenating well and whether they may need respiratory assistance. We also monitor liver function through the liver enzymes because there is a gastrointestinal hepatitis phase for Ebola, and it's important to see how severe that becomes. With of, if limited number of our patients, it was necessary to monitor other tests, such as phosphorous and magnesium. Once we had a patient who received complete renal replacement therapy, essentially dialysis, because those particular electrolytes are disturbed as a result of the treatment. It is becoming apparent that in many cases of Ebola, creatine kinase, which is an enzyme that's released when muscle is lysed, is important as some patients do show signs and symptoms of rhabdomyolysis, or muscle lysis. The test menu itself may actually look quite large although it really is quite limited to just those things and a few minor other components that may be of importance predominantly because they may be secondary things that show up in patients in the hospital in general. So, we offer gastrointestinal pathogen testing, respiratory pathogen testing, and we're now offering blood culture identification of organisms in the SCDU laboratory. One consideration for the lab layout is that we are opening sample tubes that have a category A pathogen in them. So we perform that testing in a class two biosafety cabinet to protect the operator more than anything else. Our hematology analyzer that does our blood counts does not require opening of the tube, so it's not present in the safety cabinet. It actually pierces the blood tube itself and has minimal risk of aerosolization or other risk of contaminating the environment. Also, our PCR-based testing for nucleic acids is outside of our safety cabinet because the sample itself is mixed with a reagent that completely inactivates the virus prior to loading it into the instrument. So we do that mix, mixing in the biosafety cabinet prior to loading the instrument, and then the instrument itself resides outside of the safety cabinet. So in an effort to maintain the highest levels of safety for our laboratory personnel as they handle these known positive patient samples, they utilize the full powered air purifying respirator, or PAPR. It consists of an initial layer of paper scrubs, which is then covered by a Tyvek coverall. A standard pair of gloves is then placed onto that and taped down to the Tyvek suit. There's an extended cuffed set of gloves that's placed over that. There are Tyvek booties that are placed over the feet even though the feet are covered by the Tyvek coverall. And then PAPR hood, which is an air purifying respirator unit with a large clear face shield that allows wide field of vision for the operator. The Tyvek suit has a zipper down the front, and we determined that that was a, an potential area of leakage. So there is an impervious apron that's placed over that zipper as well. And as we discovered very quickly with one of our staff, it is critically important that if you wear corrective lenses that you put your eye glasses on before donning all of the PPE. All of our donning and doffing is observed so that there are two individuals who are making sure that all of the processes are followed, the individual wearing the personal protective equipment and the individual observing it. Therefore, we, we also manage to keep both people safe, and we don't let fatigue create a problem for doffing for those individuals. There are also visual cues placed around the laboratory so that all of those processes are delineated in front of the individual donning or doffing. We receive a lot of questions regarding why the laboratory staff always use the full PAPR-level personal protective equipment. First and foremost, that's about comfort. There is a large, clear face shield which allows for better field of vision. And this laboratory has been part of the serious communicable diseases unit for the 12-year period that it's been open. And therefore, it's what the staff was trained to use because we didn't know what pathogens we might be dealing with. If something happened to be airborne, this would be the necessary level of protective equipment that they would use. The laboratory, like the patient room, generates a fair amount of waste. And it becomes very important that we dedicate a waste stream to these known positive samples. The known positive samples must be treated differently than, say, standard main laboratory waste because we know there is a category A pathogen in it. So the laboratory waste is placed in a biohazard bag in the laboratory itself. We add water so that when we take those samples later, take those bags to the autoclave, that there's sufficient steam produced to inactivate virus. Once the water is added to the waste bag in the laboratory, that's wound up or goose-necked, and then it is wiped clean with a germicidal wipe. It's placed in a secondary bag, which is also goose-necked and wiped with a germicidal wipe, and finally placed in an autoclave bag closed with a rubber band. That's placed in a hard plastic canister right outside the laboratory. Someone assists with this process. And that waste bag goes into that canister, and the canister is marked either positive or negative, depending on whether there are known positive samples in the canister. If they are positive, they must go to the autoclave to be autoclaved before going to incineration. And it is treated separately from the usual hospital waste stream. After testing, our staff clean the laboratory. We clean the interior and exterior surfaces of the safety cabinet, the stool they've been sitting on, the table. All available spaces they clean with germicide wipes, and clean the floor. They then proceed to doff their personal protective equipment, and between patients, we have periodically decontaminated the lab with hydrogen peroxide vapor. This is a commercial process which is known to inactivate Ebola as well as number of other pathogens. And it allows us an opportunity to get into spaces that we wouldn't normally. We have seen no effect of this hydrogen peroxide vapor on the performance characteristics of any of our laboratory equipment. We do occasionally get asked to transport additional laboratory specimens to government regulatory agencies, and we utilize the category A pathogen shipper devices to do that. Generally speaking, we attempt not to store patient samples because there are a number of reporting requirements if that's going to be performed. We do have a locked refrigerator within the anteroom that we temporarily store samples prior to being sent to government agencies. But in general, we try to keep the storage to a minimum. We also do monitor the disposition of all of our samples so that we know whether any blood sample is either transported to a government agency or destroyed. We do not, we have not, performed any biopsies for our patients with Ebola. The acute illness is really prioritized over a longer term concern. However, specimens that are collected, for instance, fine needle aspirations or biopsies, could be inactivated by tenth percent formalin with sufficient residence time and volume so that there's complete tissue penetration by the formalin. One of the most important things we learned in our activation is a culture of safety related both to the laboratory as well as all of the patient care areas of our unit. There's a shared accountability for safety. Any individual is empowered to notify an individual if they think that they have not followed protocol. Within the family rules that we have within the unit, there are accountability things built into that. I will follow all of the standard operating procedures. I will ensure others follow all standard operating procedures. Effective and assertive communication is absolutely central to the safety of everyone involved in the patient care. We also had a lot of direct pare, patient care communication. This becomes critical also with our doctors, and we are in such close proximity in the unit, this really is a very minor issue. We also participated in the laboratory in the daily team huddles so that we knew exactly what laboratory tests were needed and when they were needed so that we could plan accordingly to make sure that the infrastructure and resources were available as necessary. There are really only a few critical points to make when it comes to laboratory for Ebola patients. Dedicated laboratory for Ebola patients is really not entirely necessary although may be preferred for known positive Ebola patients. The amount of testing that's needed, the, the particular tests that are necessary for acute care of patients with Ebola, is really quite limited. And we have to be very careful and make sure that we provide safe specimen transport to protect the operators, the transporters, and the public in general. Thank you for attention to this lesson.
