Young child with bilateral conjunctival injection. (Photo courtesy of Dr. Kenneth Yen, with permission.)

Purpose

The purpose of this report is to provide EMS professionals with situational awareness of COVID-19 illness in pediatric patients. The overarching EMS considerations when caring for infants, children and teens during the COVID-19 pandemic are: 

  1. Recognition of the often atypical and mild – but sometimes life-threatening – presentation of pediatric COVID-19, including the newly described, severe, Multisystem Inflammatory Syndrome in Children (MIS-C)
  2. Use of appropriate PPE and modified medical procedures to reduce risk of transmission to EMS professionals of the SARS-CoV-2 virus that causes COVID-19
  3. Prompt transport to an appropriate ED for evaluation and treatment of any ill infant, child or teenager with known or possible COVID-19, even if signs/symptoms are mild or atypical.

Background and Significance

At the outset of the COVID-19 pandemic, initial reports – especially from China and other Asian countries – suggested that infants and children seemed to be relatively spared from widespread or severe COVID-19 illness.1 Indeed, according to the CDC,1 infants and children overall account for less than 5% of COVID-19 cases in the United States, although this percentage may be higher in specific regions.2

This relatively low number likely reflects under-reporting, as very little COVID-19 diagnostic testing was performed in infants, children and teens, especially for asymptomatic individuals and early in the pandemic.3 It is also true that infants and children typically experience only mild symptoms similar to a “cold.”1,3-5

Since late April 2020, however, several hundred cases of an acute, potentially fatal, multi-system inflammatory syndrome with atypical signs and symptoms associated with pediatric COVID-19 have been reported worldwide6-10 and in at least 20 US states.11-13 This newly recognized syndrome is called “Multisystem Inflammatory Syndrome in Children” (MIS-C) associated with COVID-19.14,15.  Although it is most common in young, school age children, it may be seen in patients ranging from newborn9 to up to 19 or 21 years of age.14,15

Additionally, infants and children (like adults) often shed and spread to others the SARS-CoV-2 virus that causes COVID-19, even when they are asymptomatic.3,16,17

A high index of suspicion for COVID-19 must therefore be maintained when caring for any infant or child during the COVID-19 pandemic, even for those with mild symptoms and for those with atypical signs and symptoms that could be caused by COVID-19. Moreover, similar to adults, EMS clinical practice guidelines and procedures should be modified when possible, in order to minimize the use  of Aerosol generating procedures (AGPs) that increase the risk of virus transmission to EMS professionals.18-20

Five Steps for EMS Evaluation and Care of Pediatric COVID-19

1. Use appropriate PPE for all team members within six feet of the patient.

As with adults, “PPE before ABCs” should be used for all EMS encounters prior to initiating patient contact. One EMS professional (“scout”), in at least the minimum level of PPE  shown in Figure 1 (mask + eye protection + gloves), should screen the patient (from a six-foot distance) prior to entering the scene,20 in order to help determine the level of PPE that will be needed. He or she should also supply additional surgical masks on-scene.

The parent or caregiver should place a surgical mask on any patient at least two years of age, on himself/herself, and on any other family members on-scene as soon as possible, preferably before EMS professionals initiate close-range patient care. This critical step is called “source control.”20-23

There is no perfect or standardized set of PPE garments to protect against the SARS-CoV-2 virus that causes COVID-19, especially during the current pandemic. Selection of the specific components of a PPE ensemble will vary according to COVID-19 prevalence in the community, PPE availability, training, the results of patient screening, evolving expert guidance20-22 and many other variables. A few general recommendations, however, are summarized in Table 1.

A representative PPE decision-making algorithm is shown in Figure 1:

Figure 1: COVID-19 PPE Algorithm (UT Southwestern/Parkland BioTel EMS System, with permission)

2. Consider the possibility that any infant, child or teen may have COVID-19.

This is the same as for adults. The likelihood of pediatric COVID-19, however, was not generally recognized until recently. (Moreover, even on an adult EMS call, asymptomatic pediatric family members present on-scene could potentially spread the SARS-CoV-2 virus to EMS team members.)

Pediatric patients are less likely to have typical “adult” COVID-19 symptoms (fever, cough and shortness of breath). 1,3-5,24-26 Rather, they are more likely to have only mild, “cold”-like symptoms, such as nasal congestion, runny nose, or sore throat. Such mild disease and uneventful recovery appear to be most common course for pediatric patients with COVID-19.

Rarely, however, pediatric patients may suddenly develop Multisystem Inflammatory Syndrome in Children (MIS-C) either during or (more likely) up to several weeks after a known or suspected COVID-19 illness or even in previously asymptomatic children.8 While currently rare, there have already been several hundred case reports of MIS-C and several deaths.1,8,27,28

MIS-C condition can progress rapidly to distributive or cardiogenic shock, multi-system organ dysfunction or cardiac arrest. It is therefore imperative to screen carefully for any of the worrisome, multi-system signs and symptoms14,15 listed in Table 2, especially if they are associated with persistent fever of at least 38°C or 100.4°F lasting at least 24 hours. 

Special attention should be paid to thorough evaluation of children with asthma, obesity, weakened immune systems or other, chronic medical conditions. As in adults, these children with COVID-19 are at higher risk for a severe clinical course and perhaps for MIS-C.26,29

Figures 2 through 5 depict physical findings that resemble those associated with MIS-C. Figure 6 depicts “COVID-toes,” which appear to be a unique feature of pediatric (and less commonly, adult) COVID-19 illness.

Figure 2: Bilateral conjunctival injection (conjunctivitis) without purulent draining (VisualDx.com, with permission)
Figure 3: Hemorrhagic crusting of lips and oral mucosa, erythema of cheeks (VisualDx.com, with permission)
Figure 4: “Strawberry tongue” (VisualDx.com, with permission)
Figure 5: Skin rash on hands and arms, swollen hands (VisualDx.com, with permission)
Figure 6: “COVID toes” (Courtesy of Dr. Amy Paller, Northwestern University, with permission)

3. Minimize use of AGPs to reduce risk of disease spread to EMS personnel.

Like adults, infected children – even those who are asymptomatic or minimally symptomatic – can shed the SARS-CoV-2 virus and may still be able to spread it to EMS professionals.3,16,17 Therefore, similar to adults, use of proper PPE and modification of routine EMS clinical practice guidelines can be useful to help reduce the risk of virus transmission.

The SARS-CoV-2 virus that causes COVID-19 is spread primarily through respiratory droplets via close person-to-person contact, similar to seasonal influenza virus. Close-range aerosol spread also occurs.22 Moreover, viral shedding even by asymptomatic persons is possible.1,16,17 Recent experience with COVID-19 and with past illnesses caused by similar coronaviruses, such as SARS and MERS, has shown that aerosol-generating procedures (AGPs) pose high risk of virus transmission to healthcare professionals.19,30-33

As such, EMS clinical care guidelines during the COVID-19 pandemic need to be modified when possible, regardless of whether the patient (adult or pediatric) has known or suspected COVID-19 and regardless of whether the presentation is mild or severe. One important modification entails reduced use and modification of AGPs.20,30,32

There is no standardized, “official” list of AGPs.20,33 Table 3 lists medical procedures that may be considered AGPs commonly used in EMS.

Representative examples of AGP modifications are described below:

  • If possible, perform AGPs in in a stationary ambulance with the rear doors opened and the HVAC system activated20
    • Since the virus spreads readily indoors in enclosed spaces, performing AGPs outdoors may be another good option, if feasible34-38
  • Minimize the number of personnel within six feet of the patient, especially during AGPs20
  • Apply “source control” for respiratory droplets as early as possible, with a surgical mask for any patient at least two years of age (if tolerated) and for parents/caregivers and bystanders on-scene20-23
    • The surgical mask may be reapplied over the nasal cannula, if the patient requires supplemental oxygen
    • Note: There is no expert recommendation or scientific rationale to apply an N95 respirator on a pediatric (or adult) patient, for several reasons:
      • Fit & seal: Adult N95 respirators will not fit an infant or small child, and neither fit-testing nor “seal check” is practical for an acutely ill patient39
      • N95 respirators are designed to protect the wearer from inhaled droplets, not to protect others from the wearer’s exhaled droplets40
      • Scarcity and cost41
      • Lack of N95 superiority versus standard surgical/procedure mask (at least for non-AGP patient care)42-44
      • Prolonged wear of a properly fitted N95 can be associated with decreased oxygen saturation and increased PetCO2, under both laboratory and clinical conditions45-47 – this could worsen the patient’s respiratory physiology
  • Minimize supplemental oxygen flow to achieve oxygen saturation of at least 94%
  • Minimize use of nebulized bronchodilators
    • Use only if wheezes are present, along with a current/past history consistent with asthma or similar chronic condition associated with acute bronchospasm; or if signs/symptoms are consistent with croup (nebulized epinephrine)
    • If available, assist the patient with his/her own MDI instead of using nebulized medications
  • Minimize use of intranasal (IN) medications, in favor of IM or IV/IO, when possible
  • Strongly consider IM epinephrine (rather than inhaled bronchodilators) as the initial treatment of moderate-severe, acute bronchospasm, such as asthma (and especially for anaphylaxis)
  • For assisted BVM ventilation, use a two-person technique and maintain a tight seal:
    • Use a PEEP valve, if available
    • Use a viral/bacterial filter, if available
      • Caveat: Typical “adult” viral filters have minimum tidal volumes and dead space that may preclude their use in smaller pediatric patients. Use of a pediatric filter can mitigate these limitations. Refer to manufacturer specifications to determine selection of appropriate filter size.
    • Use a gentle, one-handed bag squeeze
    • Use minimal force and volume to achieve chest rise
    • Avoid excessive ventilation rate
  • Endotracheal intubation poses the highest risk of virus exposure for healthcare providers. As such, for advanced airway management, use of a supraglottic airway (SGA) by the most experienced provider on-scene is preferred over endotracheal intubation
    • If endotracheal intubation must be performed, video laryngoscopy is preferred over direct laryngoscopy
    • A viral or bacterial filter should be used, if available and may be pre-loaded onto an SGA before insertion (see Caveat, above)
  • For CPR, an advanced airway should be inserted as soon as possible, without interrupting chest compressions:
    • This modification from previous, standardized “CAB” cardiac arrest management is consistent with new American Heart Association Life Support recommendations due to COVID-1948
    • This shift to early source control using an advanced airway may be particularly important, since at least one recent simulation study found that N95 filtering facepiece respirators may not provide sufficient protection for rescuers during CPR49
    • Although early field termination of resuscitation efforts for known COVID-19 adult patients is being used in some jurisdictions throughout the United States, this is not a common practice for pediatric patients – EMS professionals should consult their own local guidelines on this topic

4. Always offer and strongly encourage transport to an appropriate ED for any ill infant child, teen or young adult (21 years old or less) with known or suspected COVID-19 (even if symptoms appear mild or atypical).

During the COVID-19 pandemic, EMS professionals should resist the temptation to attribute apparently minor signs/symptoms in pediatric patients, such as fever, “pink eye” or rash, to minor, self-limited illnesses for which EMS- or parent-initiated transport refusal is appropriate.

Based on available data from recent case reports, MIS-C may progress rapidly from relatively mild symptoms to shock and cardiac arrest. As such, prompt transport to an appropriate ED for evaluation and treatment is critical. This is especially important for a pediatric patient with a chronic, underlying medical condition.26,29 MIS-C is a reportable condition14 – this is another important reason why all such pediatric patients should be transported to a hospital.

While specific destination decision-making decisions will vary by agency and jurisdiction, a pediatric hospital may be better prepared and equipped than an adult hospital to evaluate and treat pediatric patients under 18 years of age with possible COVID-19, especially MIS-C.

During the COVID-19 pandemic, parental refusal and non-transport for pediatric patients with fever or any of the worrisome signs or symptoms suggestive of either COVID-19 or MIS-C should be discussed in real time with online medical control, preferably a physician or other consultant familiar with the unique features of pediatric COVID-19.

5. Notify online medical control and/or receiving hospital directly while en route with a known or suspected pediatric COVID-19 patient.

Many hospitals – especially those in areas of high community prevalence of COVID-19 – have implemented special EMS hand-off procedures during the COVID-19 pandemic. Advance notification by EMS is imperative for both adult and pediatric patients, in order to expedite care and minimize risk of virus spread in the ED. 

Outcome

Large series of pediatric COVID-19 patients in the US have not yet been published. Thus far, most pediatric patients have recovered well from COVID-19. There is at this time no way to predict which of these patients will go on to develop MIS-C. Fortunately, many children with MIS-C associated with COVID-19 have also recovered well with intensive hospital treatment.

This often entails PICU care, including: vasopressor and inotrope support; ventilator support; anti-inflammatory and immunomodulator treatment; and other specialized, critical care. Despite these efforts, however, a high percentage of these patients will develop serious cardiac or other complications9,12,26,28 and several fatalities have been reported.

Summary

In contrast to early reports during the 2020 pandemic, COVID-19 can and does affect infants, children and teenagers. Moreover, a newly recognized, acute, potentially fatal, multi-system inflammatory syndrome (MIS-C) may appear days to weeks after acute infection with the SARS-CoV-2 virus. Medical science and best practices for clinical care of both pediatric COVID-19 illness and MIS-C are evolving. 

Until these illnesses are better understood, EMS professionals must consider the possibility of COVID-19, even in newborn infants, despite atypical or mild symptoms. They must likewise recognize the fever and other worrisome signs and symptoms that might represent MIS-C. And they must use appropriate PPE, infection control measures, and minimization or modification of aerosol-generating procedures in order to reduce the risk of personnel exposure.

Finally, the safest plan is to transport symptomatic pediatric patients to the ED for evaluation and care, especially those with fever and any of the signs or symptoms of MIS-C. Transport refusals should be managed with real-time consultation with online medical control, preferably with a physician familiar with the unique features of pediatric COVID-19.

References

  1. CDC COVID-19 Response Team. Coronavirus Disease 2019 in Children — United States, February 12–April 2, 2020. CDC MMWR Weekly / April 10, 2020 / 69(14);422–426.
  2. Dallas County Health and Human Services 2019 Novel Coronavirus (COVID‐19) Summary, May 15, 2020
  3. Cruz AT and Zeichner SL. COVID-19 in Children: Initial Characterization of the Pediatric Disease. Pediatrics. 2020;145(6):e20200834.
  4. Xia W, Shao J, Guo Y, Peng X, Li Z, Hu D. Clinical and CT features in pediatric patients with COVID‐19 infection: Different points from adults. Pediatric Pulmonology (2020) 55:1169-1174. https://doi.org/10.1002/ppul.24718.
  5. She J, Liu L, Liu W. COVID-19 epidemic: Disease Characteristics in Children. J Med Virol. 2020:1-8. DOI: 10.1002/jmv.25807.
  6. PICS Statement: Increased number of reported cases of novel presentation of multi-system inflammatory disease. Paediatric Intensive Care Society UK, April 27, 2020.
  7. Qiu L, Jiao R, Zhang A, Chen X, Ning Q, Fang F, et al. A Typical Case of Critically Ill Infant of Coronavirus Disease 2019 With Persistent Reduction of T Lymphocytes. Pediatr Infect Dis J. 2020. Epub ahead of print 2020/05/08.
  8. Riphagen S, Gomez X, Gonzales-Martinez C, Wilkinson N, Theocharis P. Hyperinflammatory shock in children during COVID-19 pandemic. Lancet. 2020. Advance online publication, doi: 10.1016/S0140-6736(20)31094.
  9. Verdoni L, Mazza A, Gervasoni A, et al. An outbreak of severe Kawasaki-like disease at the Italian epicentre of the SARS-CoV-2 epidemic: an observational cohort study [published online May 13, 2020]. Lancet. doi:10.1016/ S0140-6736(20)31103-X.
  10. Kamali Aghdam M, Jafari N, Eftekhari K. Novel coronavirus in a 15-day-old neonate with clinical signs of sepsis, a case report. Infect Dis (Lond). 2020;52(6):427-9. Epub 2020/04/03.
  11. Jones VG, Mills M, Suarez D, et al. COVID-19 and Kawasaki disease: novel virus and novel case. Hosp Pediatr. 2020; doi: 10.1542/hpeds.2020-0123.
  12. DeBiasi RL, Song X, Delaney M, Bell M, Smith K, Pershad J, Ansusinha E, et al. Severe COVID-19 in Children and Young Adults in the Washington, DC Metropolitan Region. J Pediatr (2020), doi: https://dx.doi.org/10.1016%2Fj.jpeds.2020.05.007 (in press).
  13. NYC Health. 2020 Health Alert #13: Pediatric Multi-System Inflammatory Syndrome Potentially Associated with COVID-19. 5 May 2020.
  14. CDC Multisystem Inflammatory Syndrome in Children (MIS-C). Retrieved from: https://www.cdc.gov/mis-c/hcp/.
  15. World Health Organization. Multisystem inflammatory syndrome in children and adolescents temporally related to COVID-19, Scientific Brief. 15 May 2020.
  16. Heneghan C, Brassey B, Jefferson T. COVID-19: What proportion are asymptomatic? The Centre for Evidence-Based Medicine.  Published online, April 6, 2020.
  17. Dong Y, Mo X, Hu Y, Qi X, Jiang F, Jiang Z, Tong S. Epidemiology of COVID-19 Among Children in China. Pediatrics. 2020; 145(6):e2020070.
  18. CDC Novel Coronavirus 2019 (COVID-19). Healthcare Infection Prevention and Control FAQs for COVID-19.
  19. Tran K, Cimon K, Severn M, Pessoa-Silva CL, Conly J. Aerosol Generating Procedures and Risk of Transmission of Acute Respiratory Infections to Healthcare Workers: A Systematic Review. PLoS One. 2012; 7(4): e35797.
  20. CDC Coronavirus 2019 (COVID-19). Interim Guidance for Emergency Medical Services (EMS) Systems and 911 Public Safety Answering Points (PSAPs) for COVID-19 in the United States. Retrieved from: https://www.cdc.gov/coronavirus/2019-ncov/hcp/guidance-for-ems.html.
  21. CDC Coronavirus 2019 (COVID-19). Using Personal Protective Equipment (PPE). Retrieved from: https://www.cdc.gov/coronavirus/2019-ncov/hcp/using-ppe.html.
  22. CDC Coronavirus 2019 (COVID-19). Interim Infection Prevention and Control Recommendations for Patients with Suspected or Confirmed Coronavirus Disease 2019 (COVID-19) in Healthcare Settings. Retrieved from https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-recommendations.html.
  23. Patel RB, Skaria SD, Mansour M, Smaldone GC.  Respiratory source control using a surgical mask: An in vitro study. J Occup Environ Med (2016);13(7):569-576. https://doi.org/10.1080/15459624.2015.1043050.
  24. Castagnoli R, Votto M, Licari A, Brambilla I, Bruno R, Perlini S, et al.  Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection in Children and Adolescents -A Systematic Review. JAMA Pediatrics (2020). Published online, April 22, 2020. https://doi.org/10.1001/jamapediatrics.2020.1467.
  25. Zimmerman P, Curtis N. Coronavirus Infections in Children Including COVID-19. Pediatr Inf Dis J (2020). 39(5):355‐368. https://doi.org/10.1097/inf.0000000000002660.
  26. Zachariah P, Johnson CL, Halabi KC, Ahn D, Sen AI, Fischer A, et al. Epidemiology, Clinical Features, and Disease Severity in Patients with Coronavirus Disease 2019 (COVID-19) in a Children’s Hospital in New York City, New York. JAMA Pediatr (2020). Published online June 3, 2020. doi:10.1001/jamapediatrics.2020.2430.
  27. Janney E. Death Of Teen Linked To Coronavirus: Baltimore County Officials. Yahoo News, May 19, 2020.  Retrieved from: https://news.yahoo.com/first-pediatric-coronavirus-death-baltimore-151549156.html.
  28. Levin M. CDC COCA Webinar. Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with Coronavirus Disease 2019 (COVID-19), May 19, 2020. Retrieved from: https://emergency.cdc.gov/coca/calls/2020/callinfo_051920.asp.
  29. Shekerdermian LS, Mahmood NR, Wolfe KK, et al.  Characteristics and Outcomes of Children with Coronavirus Disease 2019 (COVID-19) Infection Admitted to US and Canadian Pediatric Intensive Care Units. JAMA Pediatr. 2020 May 11. doi: 10.1001/jamapediatrics.2020.1948. [Epub ahead of print].
  30. Christian MD, Loutfy M, McDonald C, Martinez KF, Ofner M, Wong T, et al. Possible SARS Coronavirus Transmission During Cardiopulmonary Resuscitation.  Emerg Infect Dis (2004). 10(2):287-293.
  31. Ari A. Practical strategies for a safe and effective delivery of aerosolized medications to patients with COVID-19. Resp Med (2020) 167:105987 epub: https://doi.org/10.1016/j.rmed.2020.105987.
  32. Caputo KM, Byrick R, Chapman MG, Orser BJ, Orser BA. Intubation of SARS patients: infection and perspectives of healthcare workers. Can J Anesth (2006); 53(2):122-129.
  33. Simonds A. ‘Led by the science’, evidence gaps, and the risks of aerosol transmission of SARS-COV-2. Resuscitation (2020), in press. https://doi.org/10.1016/j.resuscitation.2020.05.019.
  34. State of Connecticut. General EMS Guidance during COVID-19. Retrieved from: https://portal.ct.gov/-/media/Departments-and-Agencies/DPH/dph/ems/pdf/statewide_protocols/v20201ProtocolsMarch2020v2APPENDIX4.pdf?la=en.
  35. Indiana Department of Homeland Security. COVID19 Aerosol Generating Procedures. Retrieved from: https://www.in.gov/dhs/files/IDHS%20CVODI19%20EMS%20Aerosol%20Generating%20Procedures%20Protocol%2003202020.pdf.
  36. American Red Cross. Transmission-Based Precaution Guidelines for COVID-19. Retrieved from: https://www.redcross.org/take-a-class/coronavirus-information/transmission-based-precautions-and-prevention.
  37. Stadnytskyi V, Bax CE, Bax A, Anfinrud P. The airborne lifetime of small speech droplets and their potential importance in SARS-CoV-2 transmission. PNAS June 2, 2020 117 (22) 11875-11877; first published May 13, 2020 https://doi.org/10.1073/pnas.2006874117
  38. Qian H, Miao T, Liu L, Zheng X, Luo D, Li Y. 2020. Indoor transmission of SARS-CoV-2. Preprint retrieved from: https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1 doi: https://doi.org/10.1101/2020.04.04.20053058.
  39. CDC NIOSH. Filtering out Confusion: Frequently Asked Questions about Respiratory Protection. Retrieved from: https://www.cdc.gov/niosh/docs/2018-130/pdfs/2018-130.pdf?id=10.26616/NIOSHPUB2018130.
  40. CDC Coronavirus 2019 (COVID-19). Personal Protective Equipment: Questions and Answers. Retrieved from: https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirator-use-faq.html.
  41. CDC Coronavirus 2019 (COVID-19). Strategies for Optimizing the Supply of N95 Respirators. Retrieved from: https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/index.html.
  42. Iannone P, Castellini G, Coclite D, Napoletano A, Fauci AJ, Iacorossi L, et al. The need of health policy perspective to protect Healthcare Workers during COVID-19 pandemic. A GRADE rapid review on the N95 respirators effectiveness. PLOS ONE 15(6): e0234025. Published online June 3, 2020. https://doi.org/10.1371/journal.pone.0234025.
  43. Lepelletier D, Grandbastien B, Romano-Bertrand S, Aho S, Chidiac C, et al. What face mask for what use in the context of COVID-19 pandemic? J Hosp Infect (2020): Preproof. https://doi.org/10.1016/j.jhin.2020.04.036.
  44. Long Y, Hu T, Liu L, Chen R, Guo Q, Yang L, et al. Effectiveness of N95 respirators versus surgical masks against influenza: A systematic review and meta-analysis. J Evid Based Med (2020):1-9, Published online. DOI: 10.1111/jebm.12381.
  45. Roberge RJ, Coca A, Williams WJ, Powell JB, Palmiero AJ. Physiological Impact of the N95 Filtering Facepiece Respirator on Healthcare Workers. Resp Care (2010);55(5):569-577.
  46. Kim JH, Benson SM, Roberge RJ. Pulmonary and heart rate responses to wearing N95 filtering facepiece respirators. Am J Inf Control (2013);41:24-27. doi:10.1016/j.ajic.2012.02.037.
  47. Kao TW, Huang KC, Huang YL, Tsai TJ, Hsieh BS, Wu MS. The physiological impact of wearing an N95 mask during hemodialysis as a precaution against SARS in patients with end-stage renal disease. J Formosan Med Assoc Taiwan (2004);103(8):624-628.
  48. Interim Guidance for Life Support for COVID-19. 9 April 2020. Circulation. Epub ahead of print. 10.1161/CIRCULATIONAHA.120.047463. Retrieved from: https://www.ahajournals.org/doi/abs/10.1161/CIRCULATIONAHA.120.047463.
  49. Hwang SY, Yoon H, Yoon A, Kim T, Lee G, Jung KY, et al. N95 filtering facepiece respirators do not reliably afford respiratory protection during chest compression: a simulation study.  Am J Emerg Med (2020);38:12-17. https://doi.org/10.1016/j.ajem.2019.03.041.