Learning Curves Spirometry Video: 5: Spirometry Testing

A well-trained technician is essential for obtaining accurate and precise spirometry test results. It is critical that the spirometry technician be able to instruct subjects and coach them to give maximum effort for each maneuver. In this module, you will learn about preparing your test area, asking pre-screening questions, preparing the subject, and performing the spirometry test. These steps will help you and the worker produce the most technically accurate spirometry possible. Each organization should have established guidelines for infection control, equipment maintenance, testing protocols, and emergency procedures. Documentation and retention of quality assurance records cannot be overemphasized. Safety is the number one priority of any medical testing program. Hazards should be minimized before the worker enters the testing room. This includes proper equipment maintenance and infection control procedures. Emergency procedures should be established and supportive equipment available. All testing personnel should be trained in equipment use. Most spirometry systems used in occupational health programs require single patient use mouthpieces or filters for the breathing tubes that come in direct contact with the worker. However, spirometry equipment must still be sanitized regularly. The operator's manual should have instructions for proper cleaning. While testing, technicians should not handle used mouthpieces or contaminated equipment without gloves. Wash or sanitize your hands before advancing to the next test or if you come in contact with contaminated equipment. Some studies suggest that standing versus sitting can have a small effect on spirometry results. Although either posture can be used, slightly larger values have been measured in the standing posture and OSHA recommends that testing be conducted in this position. Pregnant women, obese men or women, and children should use the standing position to obtain the best results. Use a testing area free from distraction that provides privacy and confidentiality. This can be a private room, screen or curtain. Pre-test questions are essential in order to determine if it is appropriate to conduct testing. Although spirometry is very safe, there are situations when spirometry should not be performed. Your organization should provide you with guidelines for postponing spirometry. If you have a question whether to proceed, seek the advice of the responsible health care professional. Let's watch as the technician asks the worker pre-screening questions. Your facility may use different criteria for postponing testing. Good morning. I'm Diana. Are you the shift foreman? Yes. Okay. Well, the first thing we need to do is get some questions. Won't you have a seat, please? Have you had a cold, flu or respiratory infection in your chest within the last three weeks? If the subject has had a recent respiratory infection, consider postponing the test until at least three weeks after the symptoms have passed or longer if there is a lingering cough or pain. These illnesses may affect test results. Have you had any surgeries to your chest, abdomen, head or eye, including LASIK? This includes oral and LASIK surgeries where the employee can report to work the day following this procedure. If your organization does not have post-operative guidelines, consult with your surgeon for test clearance. If the worker has had a heart attack or stroke within the last 30 days, a clearance form from the treating physician is needed before the worker can perform spirometry. Have you coughed up any blood of an unknown origin within the last six weeks? The cause of hemoptysis, or coughing up blood, should be determined before performing spirometry. Hemoptysis of unknown origin is a contraindication for spirometry testing. Have you ever been told by a doctor that you have an aneurysm or a weakness in a major blood vessel? Forcefully exhaling can dramatically increase the pressure inside the head, chest and abdomen. These increased pressures can cause an existing aneurysm to rupture and create a life-threatening situation. Workers with an untreated aneurysm should not perform spirometry. If the test is postponed, be sure to reschedule before the worker leaves the testing facility. Record the date and the reason for the postponement. Some workers use aerosolized medications to control certain medical conditions. And do you use an inhaler for your breathing? Yes. Okay, and can you pick it out on this chart for me? It looks like this one. Document, both in the record and on the spirometry report, the name of the medication, how often the worker takes it, and the time of the last dose. If there are no contraindications for performing spirometry, demographic information can now be recorded. What is your birth date, Gary? January 14, 1974. And what race do you consider yourself? White. Record the worker's race and or ethnicity. And we need to get your height and weight without shoes. If you could take your hard hat off and your shoes off. Measure the worker's height and weight in stocking feet. In the following section, you will see examples of spirometry testing. We're joining the testing after all pre-test procedures have been completed. Okay, so Tyler, what we're going to do is a breathing test. And this test is going to measure how much air you can fill your lungs up with and the force and speed that you can blast it out. Before we get started, I just want to go over a couple instructions on how to do a maneuver. And we'll get the tube together for you, and we'll get you going. Okay, sounds great. Okay, so I'm going to hand you this tube, okay? And this tube will be inside this handheld device. It's very sensitive. Whenever I hand it to you, Tyler, just kind of hold it here. Don't wave it around or make any gestures with it. It's very sensitive, okay? At this point, you'll have a nose clip on. And then I'll say, okay, Tyler, I need you to take a nice, big, deep breath, as deep as you can, put this tube in your mouth, and then blast your air through the tube. Whenever you put this in your mouth, it needs to be a good inch and a half between your teeth so it depresses your tongue out of the way. Use your lips to form a nice, tight seal so none of the air escapes around the sides, okay? Now, after the first second, it's going to feel like that you don't have any air left in your lungs. That is the point where I don't want you to engage the muscles in your neck and shoulders. Don't bear down. Just stay nice and tall, nice and relaxed. Keep your airway open, okay? So it's going to look like this. You'll have a nose clip on. I'll ask you to take a nice, big, deep breath, as deep as you can, put the tube in your mouth, blast your air through the tube, and it'll look like this. Let's discuss each part of the test. After preparing your test area, checking the calibration of your spirometer, and asking the pre-test questions, you should give a short explanation of the test. Position the subject. Be sure the subject is not directly facing you during the test. The worker should loosen or remove any tight clothing that may restrict them from taking in their deepest possible breath. Whether testing is performed in the standing or seated position, the worker must maintain an upright posture. The chin should be slightly elevated and the neck slightly extended to allow for the most forceful exhalation possible. Both feet should remain flat on the floor. Dentures should be left in place if they are not loose. Slightly loose dentures can be left in if the worker bites lightly on the mouthpiece. It is difficult to maintain a tight lip seal around the mouthpiece without dentures. If dentures remain in place, then examine the spirograms to determine if the dentures are obstructing the worker's exhaled airflow. Both airflow obstruction and removal of dentures should be documented in the worker's chart. This section is critical to learn and practice. Technicians can't be shy about performing an enthusiastic demonstration of the test maneuver. Be sure not to directly face the subject while doing the demonstration. Notice the technician takes a big breath, takes in the largest amount of air possible. Mouthpiece placement is exact. The exhalation blast is very forceful. Don't end your demonstration too soon. The subject should see you continue to blow until empty. Too much vertical movement of a flow spirometer sensor can cause a spirometer to initiate a test prematurely or can produce zero flow errors. Warn the subject not to move the handle or mouthpiece while the machine sets zero flow or during testing. Small zero flow errors are common when using flow spirometers and most machines will not recognize them. These errors can be difficult to see on test results. Later, you will learn how to find zero flow errors on curves. While setting the zero flow baseline before a test, the technician or worker should block the mouthpiece completely. If you are using a portable spirometer, ask the worker to hold it so that fingers do not extend over the outlet of the breathing tube. We make sure we don't want to block the back of that tube. Even partial blockages can affect the measurements and calculated test values. Coaching should be enthusiastic during the entire maneuver. Do not shout at the worker. This may cause the person to become uncooperative. Your encouragement shows the worker that each prompt you give is important. Studies have shown that active coaching during both inhalation and exhalation help people to give a maximal effort. Watch the worker and time your instructions according to where he or she is in the sequence. If the worker is going too slowly, try to speed them up with your instruction. Ensure the worker inhales fully, gets the mouthpiece in the correct position and blasts fast and hard without hesitating. Actively coach throughout the maneuver. Continue to coach until the volume times spirogram becomes flat and no more air is being exhaled. A plateau should be seen for at least one second before stopping the maneuver. Instruct the worker that you want them to continue to blow until you tell them to stop, regardless of whether they think they are done or not. Studies show that at end exhalation, there is air movement that cannot be felt by the individual. Next, evaluate the maneuver for acceptability. You may offer the worker a seat while you are checking the technical accuracy of the most recent maneuver. Emphasize a big deep breath in and blast the air out for every maneuver. If the worker did not perform the maneuver correctly, the technician should provide specific instructions to correct that error before the next maneuver. How to identify and correct common testing errors will be reviewed later in this video. Your spirometry system should display both volume time and flow volume graphical tracings in real time as the worker blows into the spirometer. Viewing in real time allows the technician to identify errors quickly and stop the worker from continuing to blow if the maneuver will not be used due to a critical error. The volume time curve shows exhalation starting from the baseline or zero volume. Then you see a sharp vertical rise during the initial blast. This smooth continuous curve reflects maximum effort. Here we see the gradual slowing of the tracing until a flat line is drawn for one second. The flat line is referred to as the plateau and shows that the worker has reached complete exhalation. The volume time curve allows the technician to evaluate the end of test. The flow volume curve is used to determine the force of the worker's initial effort and shows details about the beginning of the test. The worker's initial hard blast is seen as a sharp rise close to the vertical axis ending with a sharp peak. This tracing from a normal healthy worker returns to the baseline and draws a triangular shape. Each curve gives us information about the acceptability of the maneuver. Use the flow volume curve to evaluate the worker's initial blast and any technical problems early in the maneuver. As the maneuver progresses, continue to look at the worker and at the volume time graph for errors that may affect the middle portion of the test. The volume time graph is also used to evaluate if the worker is able to reach a plateau and can stop blowing out. Spirometer software may also alert the technician that a plateau has been reached. Study these curves from a normal healthy worker. Use them as a model to check other tracings that may include technical errors or from workers with respiratory impairments. Recognition of changes in the shapes of these two curves will alert you to correct the worker's technique. Also, if these curves appear abnormal, the worker may need additional rest between maneuvers. It is important for all health care professionals who perform or interpret spirometry to familiarize themselves with technical errors that occur during testing. These errors can lead to inaccurate test results resulting in unnecessary medical treatment, anxiety, and even work limitations like inability to use a respirator. It is critical that the technician recognize common errors to provide specific corrective action before test interpretation. Spirometry technicians must learn to recognize the shapes of unacceptable curves and use their error recognition to stop maneuvers that will not give accurate results. The spirometer system software is not a substitute for understanding the various errors and corrective actions needed. Many spirometers do not check for all types of testing errors. We just looked at normal curves for flow volume and volume time. Next, you will learn how to check each of the curves for errors. Some of these errors can be seen while the subject is doing a maneuver. You need to recognize other errors by looking at the curves after the maneuver. Errors may not trigger an error message on your spirometer screen. You have to be smarter than the software. Our next module will give you all the tools you'll need to recognize and correct errors.