COVID-19
Introduction:
COVID-19 (coronavirus disease 2019) is a clinical syndrome caused by “SARS-CoV-2” virus, which is a non-segmented, positive sense RNA virus belonging to family of coronaviruses.
Presentation:
Majority of patients present with respiratory symptoms (shortness of breath, cough), constitutional symptoms (fever, chills, fatigue) and gastrointestinal symptoms (diarrhea, nausea, vomiting). Other symptoms include myalgias, headache, and loss of taste. Some patients present with significant hypoxemia without any dyspnea.
Clinical course:
Symptoms usually begin 2-14 days after exposure (median of day 4-5). Patients with bilateral viral pneumonia tend to decompensate quickly, many requiring intubation. Clinical picture is typically dominated by hypoxemic respiratory failure, some patients respond with an exuberant “cytokine storm” reaction. Patients may also develop a hypercoagulable state (disseminated intravascular coagulation)
Labs:
WBC count is usually normal.
Lymphopenia and mild thrombocytopenia are common
· Markedly elevated D-dimer levels
LDH and CRP levels are increased
Ferritin is often elevated
PCT levels and LFT’s are variable.
Imaging (CXR/CT chest):
Predominantly peripheral and basal patchy ground glass opacities
Management of non-intubated patients:
Daily labs: CBC, BMP, Mag, Phos, D-dimer, CRP
Avoid using bolus and maintenance IV fluids.
Discontinue any ACE-inhibitors or ARBs
Oxygen supplementation via nasal cannula, if increasing oxygen requirements switch to High flow oxygen (HFNC) or BiPAP
Patients on supplemental oxygen should receive dexamethasone 6 mg daily for up to 10 days
Avoid using nebulization’s unless patient is in negative pressure room. Can use MDI (metered dose inhaler) 4-8 puffs for each nebulizer treatment.
Early self-proning recommended for 12-16 hours a day
Consider using therapeutic dose Lovenox especially in patients with elevated D-dimer levels.
Management of intubated patients in ICU:
Daily labs: CBC, BMP, Mag, Phos, D-dimer, CRP
Daily morning CXR and ABG
Okay have a net positive fluid status initially in ICU. Avoid using bolus and maintenance IV fluids after first few days.
Discontinue any ACE-inhibitors or ARBs
Dexamethasone 6 mg daily for up to 10 days
Remdesivir 200 mg IV once, followed by 100 mg IV for four days for a five-day total course, can extend to 10 days course in selected cases.
Therapeutic dose Lovenox
Stress ulcer prophylaxis (PPI)
Convalescent plasma (obtained from individuals who have recovered from COVID-19) transfusion
Early proning is recommended
Low-tidal volume ventilation (≤6 mL/kg predicted body weight)
Start with higher PEEP 10 to 14
Ventilator adjustments:
Mechanical ventilation (MV) typically drives pH and pCO2, so titrate vent settings to pH and not pCO2
To achieve low tidal volumes; hypercapnia and acidosis is tolerated (pH >7.2)
Typical respiratory rate (RR) is 20 to 35 breaths/minute because tidal volumes are low
pH goal is normally 7.25 to 7.45:
If pH > 7.45, decrease respiratory rate
If pH 7.15 to 7.30, then increase respiratory rate until pH > 7.30, or PaCO2 < 25 (maximum RR= 35 breaths/minute)
If pH < 7.15, then increase respiratory rate to 35 breaths/minute
If pH still < 7.15, then perform the following:
Tidal volume may be increased by 1 mL/kg until pH > 7.15 (until plateau pressure reaches 30 cm H2O or tidal volume reaches 8 cc/kg)
Deep sedation advancing to RASS -5 if needed
If no improvement, initiate continuous paralysis
If still no improvement, initiate prone ventilation (may improve V/Q matching and better ventilation)
Sedation
Options include Precedex, Ketamine, Propofol, Midazolam, Fentanyl
Unparalyzed patients – target sedation to ventilator synchrony
Paralyzed patients – target sedation to RASS -2 to -3 using Rocuronium drips
· Extracorporeal membrane oxygenation (ECMO) for selected patients in specialized centers
· Norepinephrine should be first-line vasopressor. Vasopressin or epinephrine are options if Norepinephrine not available