Summary of COVID19 Situation and Supply Needs
* Summary of COVID19 Situation and Supply Needs: Overview document, Version 1.1, last updated 3/20/2020 @ 5:06 PM Pacific Time.
Updated FAQ significantly, added a link to medical-grade 3D printing standards. Part of the Open Source COVID19 Medical Supplies project
"COVID19 is currently spreading exponentially, in a mostly-unchecked fashion, throughout the world. Infection doubling rates are currently as high as 2-3 days. In basic models, such unchecked growth means the disease infects most of the world in just a few months. Current statistics indicate that 15-20% of people who get the disease require hospitalization for respiratory failure for multiple weeks, and often need intense and attentive care from medical professionals. These medical professionals are at severe risk while treating these highly infectious patients, and have an order of magnitude higher mortality rate than the patients themselves as a result. Treatment and care looks like oxygen therapy or intubation for weeks in highly-specialized ICUs.
If infections proceed at their current pace across the globe, we will not have enough medical supplies to prevent the higher mortality rates (8+%) Italy is seeing as of
A COVID patient usually arrives at the hospital when they develop significant shortness of breath, on day 9-10 of the illness. At this point, it is decided whether the patient needs further testing, inpatient hospitalization, or ICU care. In the early stages of the disease, the patient is given predominantly symptom based treatment and supportive care, for example medications to reduce fever and cough and adequate hydration. Non-critical inpatient hospitalizations for respiratory failure are currently given oxygen via nasal cannula, with faces covered in N95 masks to prevent aerosolized virus spread from exhalation (non-invasive oxygenation methods such as CPAP and BiPAP are avoided due to severe risk of aerosolization of virus particles).
Patients are determined to be critical if their oxygen requirements increase (hypoxemia) and they develop severe shortness of breath. In critical patients, significant deterioration in oxygenation abilities occurs within 24 hours. For the vast majority of illnesses, this results in hypoxemic respiratory failure (also known as acute respiratory failure), requiring the initiation of invasive mechanical ventilation. A minority of patients develop cardiac failure due to shock, usually from overwhelming sepsis.
The hypoxemic respiratory failure associated with COVID19 is acute respiratory distress syndrome (ARDS). This involves fluid in the interstitium of the lungs, that is not from heart failure (noncardiogenic pulmonary edema), and leads to increased stiffness in the lungs (reduced lung compliance), resulting in difficulty in ventilation. These patients respond favorably to aggressive ARDS treatment, including proning and high positive end-expiratory pressure ventilation (high PEEP ventilation). Most patients are treated early with antibiotics for suspected secondary infections (an infection acquired at the hospital), but this is discontinued based on clinical status (how the patient is doing). A minority of patients develop septic shock and require vasopressors to increase blood pressure. A subset of patients also develop heart failure.
The time course of COVID19 patients is extremely variable, but patient one from Italy was hospitalized from 02/21 to 03/11, a period of 19 days. The chart below (Lancet paper on Wuhan severe case mortality) offers guidance for development of symptoms for survivors and non-survivors
While patients are hospitalized but in non-critical condition, healthcare workers typically wear N95 masks, gowns, and gloves and sometimes face masks to prevent undue droplet-based virus contact. When patients become critical, they are moved to negative-pressure rooms in ICUs, and healthcare workers need to wear positive-pressure CAPR suits with purified regulators, because the risk of aerosolized virus is very high during intubation and critical care."
Of devices listed in the document, without links:
N95 Respirators Surgical Face Masks Goggles / Masks Powered Air Purifying Respirators (PAPR/CAPR) Examination Gloves Gowns Face Shields (Full Face Protection / FFP)
Nasal Cannulas Catheters Flow-Splitters for Oxygen Supply Thorpe Tube Flowmeter Oxygen Masks Venturi Masks (High Flow)
Negative Pressure Rooms Non-Contact Thermometers Ventilator Machines Hospital Beds Oxygen Concentrators Pulse Oximeters Non-Heated Humidifier (aka Cool-Mist) Laryngoscopes Infusion Pumps
- see also their FAQ on Making Safe Medical Devices for the COVID-19 Crisis