How might categorizing severity of illness help in the management of my patient with Covid-19?

Although the criteria for Covid-19 severity of illness categories may overlap at times or vary across guidelines and clinical trials, I have found those published in the National Institute of Health (USA) Covid-19 Treatment Guidelines most useful and uptodate.1  Keep in mind that the primary basis for severity categories in Covid-19 is the degree by which it alters pulmonary anatomy and physiology and respiratory function (see my table below).

The first question to ask when dealing with Covid-19 patients is whether they have any signs or symptoms that can be attributed to the disease (eg, fever, cough, sore throat, malaise, headache, muscle pain, lack of sense of smell). In the absence of any attributable symptoms, your patient falls into “Asymptomatic” or “Presymptomatic” category.  These patients should be monitored for any new signs or symptoms of Covid-19 and should not require additional laboratory testing or treatment.

If symptoms of Covid-19 are present (see above), the next question to ask is whether the patient has any shortness of breath or abnormal chest imaging. If neither is present, the illness can be classified as “Mild” with no specific laboratory tests or treatment indicated in otherwise healthy patients. These patients may be safely managed in ambulatory settings or at home through telemedicine or remote visits. Those with risk factors for severe disease (eg, older age, obesity, cancer, immunocompromised state), 2 however, should be closely monitored as rapid clinical deterioration may occur.

Once lower respiratory tract disease based on clinical assessment or imaging develops, the illness is no longer considered mild. This is a good time to check a spot 02 on room air and if it’s 94% or greater at sea level, the illness qualifies for “Moderate” severity. In addition to close monitoring for signs of progression, treatment for possible bacterial pneumonia or sepsis should be considered when suspected. Corticosteroids are not recommended here and there are insufficient data to recommend either for or against the use of remdesivir in patients with mild/moderate Covid-19.

Once spot 02 on room air drops below 94%, Covid-19 illness is considered “Severe”; other parameters include respiratory rate >30, Pa02/Fi02 < 300 mmHg or lung infiltrates >50%. Here, patients require further evaluation, including pulmonary imaging, ECG, CBC with differential and a metabolic profile, including liver and renal function tests. C-reactive protein (CRP), D-dimer and ferritin are also often obtained for their prognostic value. These patients need close monitoring, preferably in a facility with airborne infection isolation rooms.  In addition to treatment of bacterial pneumonia or sepsis when suspected, consideration should also be given to treatment with corticosteroids. Remdesivir is recommended for patients who require supplemental oxygen but whether it’s effective in those with more severe hypoxemia (eg, those who require oxygen through a high-flow device, noninvasive or invasive mechanical ventilation or extracorporeal membrane oxygenation-ECMO) is unclear. Prone ventilation may be helpful here in patients with refractory hypoxemia as long as it is not used to avoid intubation in those who otherwise require mechanical ventilation.

“Critical” illness category is the severest forms of Covid-19 and includes acute respiratory distress syndrome (ARDS), septic shock, cardiac dysfunction and cytokine storm. In addition to treatment for possible bacterial pneumonia or sepsis when suspected, corticosteroids and supportive treatment for hemodynamic instability and ARDS, including prone ventilation, are often required. The effectiveness of remdesivir in patients with severe hypoxemia (see above) is unclear at this time.


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  1. NIH COVID-19 Treatment Guidelines. Accessed Aug 27, 2020.
  2. CDC. Covid-19. Accessed Aug 27, 2020.  

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Massachusetts General Hospital, Harvard Catalyst, Harvard University, its affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!


How might categorizing severity of illness help in the management of my patient with Covid-19?

When should surgery be considered in my hospitalized patient with divertculitis?

Severe diffuse abdominal pain, fever, tachycardia, leukocytosis or other signs of sepsis and diffuse peritonitis indicative of free perforation requires emergent surgery. Urgent surgery should be considered when your patient fails to improve (eg, abdominal pain or the inability to tolerate enteral nutrition, bowel obstruction, or infection-related ileus) despite medical therapy or percutaneous drainage. 1,2

Lower threshold for surgical intervention is also needed in transplant patients, patients on chronic corticosteroid therapy, other immunosuppressed patients and those with chronic renal failure or collagen-vascular disease because these patients have a significantly greater risk of recurrent, complicated diverticulitis requiring emergency surgery. Overall, up to 20% of patients with acute diverticulitis undergo surgery during the same hospitalization.2

For patients with recurrent uncomplicated diverticulitis, decision regarding future elective surgery should be individualized. Although older guidelines recommended surgery after 2 attacks of uncomplicated diverticulitis, more recent guidelines place less emphasis on the number of episodes and stress the importance of considering the severity of the attacks, chronic or lingering symptoms, inability to exclude carcinoma, overall medical condition of the patient, risks of surgery, and the impact of diverticulitis on the patient’s lifestyle.1,2

Of interest, a decision analysis model suggests that elective resection after a fourth episode may be as safe as earlier resection.3



  1. Young-Fadok TM. Diverticulitis. N Eng J Med 2018;397:1635-42
  2. Feingold D, Steele SM, Lee S, et al. Practice parameters for the treatment of sigmoid diverticulitis. Dis Colon Rectum 2014;57:284-94.
  3. Salem L, Veenstra DL, Sullivan SD, et al. The timing of elective colectomy in diverticulitis: A decision analysis. J Am Coll Surg 2004;199:904-12.

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When should surgery be considered in my hospitalized patient with divertculitis?