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Oximeter Uses for Asthma Patients Categories Finger Pulse Oximeter Pediatric Oximeter Hand Held Oximeter Wrist Pulse Oximeter Sleep Unit Oximeter Pulse Oximeter Accessories Asthma is a chronic respiratory condition that is characterized by inflamed and swollen air passages that results to sudden shortness of breath and chest tightness. Patients diagnosed with asthma finds it hard to breathe normally during an asthma attack. Every day, millions of people are suffering from this condition. The narrowed airways make it difficult for air to pass through thus causing lowered oxygenation. If left unmanaged, asthma can be fatal, but with proper treatment, the prognosis of asthma is good. In this line, doctors use a pulse oximeter to find out how well a patient is doing. Any disease that involves the airways must be assessed accurately. This is due to the involvement of a person’s oxygenation. The pulse oximeter is a medical instrument that shows how much oxygen is found in the patient’s blood. In medicine, it is called the oxygen saturation in the hemoglobin. For normal results, the reading should reach at least 95 to 100 percent. Any reading lower than 95% means that there is less oxygen received into his body due to a variety of reasons. A pulse oximeter is a highly effective and accurate device for the diagnosis and monitoring of asthma. This is the very first tool used for assessing the severity if the condition because is non-invasive, portable, and generates fast results. The attending physician will simply slip the device’s probe to the patient’s finger or earlobe. A LED will transmit light through the patient’s body where the probe is attached. The device will then read how much light is absorbed and reveal the value of the quantity of oxygen saturation found in the blood. Patients with asthma or has history of asthma are often hooked to a pulse oximeter immediately upon arrival for an initial assessment. However, there are still a few which are quite doubtful and questions the ability of the pulse oximeter. Most especially when the pulse oximeter reveals the results that are not congruent to the symptoms of the patient. There are some instances that a person with asthma may have the “normal” or asymptomatic appearance, and yet the oxygen saturation is quite low. The physician will have to decide whether to perform more tests and physical assessments to strengthen his diagnosis. Nowadays, many health care units require the use of a pulse oximeter to assess and diagnose various conditions. Several studies have been performed to test the accuracy and sensitivity of pulse oximetry to patients with asthma. Most of the time, a pulse oximeter is accurate, but not absolutely Interpretation of Arterial Blood Gases in Asthma The changes in the arterial blood gases are most interesting when you observe the progression of asthma from mild to moderate to severe to extreme disease. During an Asthma Attack At the start of an asthma attack the normal PaO2 of 100 mm Hg falls (e.g. to 60mm Hg), the PaCO2 of 40 mm Hg falls (e.g. to 30 mm Hg) and the pH of 7.40 rises (e.g. to 7.50). Slowly but surely the PaO2 and the PaCO2 continue to fall and the pH continues to rise as the disease worsens. For example, the PaCO2 reaches 20 mm Hg and the pH reaches 7.60. Eventually, a state is reached wherein the lungs are unable to blow off more carbon dioxide. At this point the PaCO2 starts to rise and the pH starts to fall, but the PaO2 continues to fall. As the asthma attack gets worse and worse the low PaCO2 and the high pH start to move back toward their normal values (PaCO2 of 40 mm Hg and pH of 7.40). For example, the PaCO2 may become 30 mm Hg and the pH may become 7.50. However, the PaO2 continues to fall (e.g. to 50 mm Hg). The PaO2 is still falling and for example may now be 40 mm Hg. Eventually as the asthma attack becomes extreme, the PaCO2 rises above 40 mm Hg and may reach for example 50 mm Hg or more and the pH falls below 7.40 and may reach for example 7.30. The PaO2 continues to fall and may reach for example 20 mm Hg. After studying this data, you can see that if you draw an arterial blood gas on admission before any oxygen is given and find the PaCO2 at 50 mm Hg and the pH at 7.50, you can't tell whether the asthma attack is mild or severe. You must look at the PaO2 to distinguish these two states of asthma severity. |