Oxygen FAQ

Up to date, expert answers to frequently asked questions (FAQ) about oxygen supply systems, respiratory care and pulse oximetry written by OCC & collaborators.

Top 10 most popular FAQs

Elevated bilirubin has been reported by some studies to potentially underestimate oxygen saturation by pulse oximetry, though most available data have not shown any effect on the accuracy of Spo2 with bilirubin levels up to 84.3 mg/dlitre. The light absorption spectrum of bilirubin has a broad peak at 460 nm and two smaller peaks at 560 nm and 600 nm.  Based on this, bilirubin is relatively unlikely to have a detectable effect on the absorption of the 660 nm and 940 nm wavelengths commonly used by pulse oximeters.







▪ Two antiviral medications are effective and approved for Test to Treat: Paxlovid (nirmatrelvir/ritonavir, or NMV/r) and Lagevrio (molnupiravir, MOL). These are intended to be used in outpatient (non-hospitalized) settings. Generic versions of these medications are anticipated in upcoming months – continue to be attentive to local guidelines regarding specific details and availability.

▪ There are other treatments indicated for patients with more severe disease requiring advanced levels of care (i.e., treatment in a hospital due to severe or critical COVID-19). The goal of oral antiviral therapy is to reduce the risk of requiring an advanced level of hospital care and reduce the risk of death.

-By EPiC FHI360

▪ Symptomatic COVID-19 patients, confirmed with a positive test, within five days of onset of symptoms, and who are at risk for progression to severe disease.

▪ Patients must be age 12 or older and weigh at least 40 kilograms (88 pounds) to take NMV/r, and age 18 years or older to take MOL, but generally, the Test to Treat strategy is geared to adult patients with risk factors for developing complications.

▪ Risk factors for developing severe or critical COVID-19 include (but not limited to): Older than age 50; risk increasing substantially at age 65 and above; Chronic medical diseases such as pulmonary/lung disease, hypertension, diabetes, chronic kidney disease, immunocompromised state, HIV infection, obesity (BMI > 30kg/m2)

▪ See treatment algorithm and other resources for more details

-By EPiC FHI360

▪ It is important to reconcile or update a patient’s current medication list prior to starting oral antiviral therapy. There are important drug-drug interactions (especially for NMV/r), and there are several resources to guide dosing adjustments and/or interruptions as a patient completes their course of antiviral therapy (for example https://www.covid19- druginteractions.org/).

▪ The dosage for Paxlovid is 300 mg nirmatrelvir (two 150 mg tablets) with 100 mg ritonavir (one 100 mg tablet), with all three tablets taken together orally twice daily for five days. The full five-day course should be completed in conjunction with continued isolation according to public health recommendations.

▪ The dosage for Lagevrio (molnupiravir) is 800 mg (four 200 mg capsules) orally, every 12 hours for five days. The full five-day course should be completed in conjunction with continued isolation according to public health recommendations.

▪ The drugs can be taken with or without food. The tablets or capsules should not be cut, crushed, or broken. ▪ Drug-drug interactions should be considered; specific details and recommendations for dose adjustments can be found on the Test to Treat antiviral therapy algorithm

-By EPiC FHI360

▪ Consensus does not exist on the recommendation of NMV/r for pregnant patients. The US FDA and NIH state that for a mother and unborn baby, the benefit of taking NMV/r may be greater than the risk from the treatment, given existing animal studies and the extensive use of ritonavir in pregnant women with HIV. By contrast, WHO states that their strong recommendation for its use does not apply to pregnant patients. Decision making regarding prescription of NMV/r should be made in consultation between the patient and the health care worker, considering specific risks and benefits.

▪ Molnupiravir should not be used in pregnancy, and both men and women should be counseled to use a reliable method of contraception to avoid pregnancy within four days (females) and three months (males) of completing the course of molnupiravir.

-By EPiC FHI360

▪ Possible side effects of NMV/r include altered or impaired sense of taste, diarrhea, increased blood pressure, heart rate changes, and muscle aches. Allergic reactions, abdominal pain, nausea, and malaise have also been reported during and after NMV/r use.

▪ Possible side effects of molnupiravir include diarrhea, dizziness, and nausea.

▪ Most people have no side effects, or very mild side effects. However, patients who develop severe or distressing side effects should contact their health care team to discuss the relative risk of stopping the treatment course compared to continuing the course.

-By EPiC FHI360

▪ For those who are eligible, discuss the benefits, efficacy, and goals of treatment, along with standard counseling on common and rare side effects when prescribing any medication.

▪ For those who are NOT eligible, explain why they do not qualify for a prescription. Some patients may feel confused or upset if they cannot have the treatment for COVID-19. Reassure them that the health care team is providing the best, evidence-based treatment and care even if it cannot include oral antivirals. Any member of the health care team taking care of low-risk patients who are not eligible for oral antivirals can explain that oral antivirals are only indicated for people at risk for developing complications that may lead to death. Oral antivirals have not been shown to reduce illness severity in low-risk patients, and benefit has not been demonstrated in people at-risk who start treatment more than five days after symptom onset. Supportive symptom management at home will likely have the same therapeutic effect without the concerns for side effects of the medication.

▪ Counsel patients to remain in isolation through the course of treatment (5 days after diagnosis); After day 5, continue isolation if still having significant symptoms or requiring medication for fever and symptom control.

▪ Counsel patients about basic supportive care (i.e., rest, hydration, nutrition, analgesia, antipyretics, etc.) and about the typical progression of mild or moderate COVID-19.

▪ Tell patients if their symptoms worsen to contact a health care provider or return to the clinic for further evaluation.

▪ Counsel patients to contact the health care team if rebound symptoms occur. Rebound symptoms have been reported but are usually mild. If COVID-19 symptoms return after completion of the oral antiviral course, consider repeat testing and have the patient continue to isolate if still testing positive for COVID-19. A repeat course of oral antivirals is not indicated for rebound symptoms.

▪ If patients live with other people, consider potential exposure to those individuals and their possible risk factors. Encourage patients and families to remain vigilant and test liberally

-By EPiC FHI360

▪ The World Health Organization recommends the use of oral antivirals as part of the Living Guidelines for Treatment of COVID-19. Opencriticalcare.org features both a Test to Treat Algorithm (for clinical management) and Implementation Guide for workflows in clinical settings.

▪ Consult other training materials made available as part of this Test to Treat strategy.

-By EPiC FHI360

Anyone with symptoms should be tested, even if symptoms are mild. Symptoms include fever, cough, fatigue, loss of taste and smell, shortness of breath, sore throat, runny nose/congestion, body aches/muscle aches and, sometimes, nausea, vomiting, and/or diarrhea. It is especially important to test as early as possible once symptoms start, as oral antivirals are only effective if started within five days of symptom onset.

-By EPiC FHI360

▪ No pre-treatment renal (kidney) laboratory tests or hepatic (liver) laboratory tests are required or recommended to start oral antiviral therapy.

▪ If a patient has known chronic kidney disease with a recent eGFR of 30–60, consider adjusting the dose of NMV/r per the renal dosing guidelines. If a patient has known advanced kidney disease with eGFR < 30, NMV/r should not be prescribed. Evaluate the patient for the use of molnupiravir.

▪ If a patient does not have a recent eGFR but there is high suspicion of advanced renal disease, use clinical judgment to decide if the benefit of NMV/r outweighs the risk and/or if you can get laboratory values back in a timely manner to manage the patient accordingly.

▪ If the patient has known severe hepatic (liver) impairment disease, NMV/r should not be prescribed. Evaluate the patient for the use of molnupiravir.

▪ A pregnancy test is not required.

-By EPiC FHI360

Think we are missing something?