MUSC Lancaster Medical Center Impact Modeling

Due to recent changes in the number of reported cases of COVID-19 the hospital impact modeling is currently being updated, and this page will be revised soon.

MUSC has developed a local impact model to estimate the demands on MUSC Lancaster Medical Center from COVID-19. We used assumptions in the model as shown below. We began by specifying the demographic characteristics of each affected county. We then used DHEC daily reports on the number of confirmed cases in each county to map the estimated number of cases by age group. Then an impact matrix is used to transition these cases through the stages of illness, including hospitalization, ICU admission, and use of invasive ventilation, mortality, and recovery. Data used in this impact matrix are derived from published literature derived from other epidemics. We are updating the impact matrix with new data as they become available, and as we process more cases at MUSC we will transition to using our own internal data. The sources needed to provide care are also estimated over time for each possible scenario. Two key model parameters are (1) the prevalence of viral infection, and (2) how quickly the epidemic progresses over time. To quantify these two parameters we are using estimates of accumulated cases provided by DHEC, and fitting the epidemic curve to that seen in other locations (see graphic below for illustration). Adjustments are made for undiagnosed cases following DHEC estimation techniques. The model is regularly updated based on calibration to what we see in terms of number of cases identified, and from data derived from our own health system over time.

Model Assumptions:

  1. Percent infected but are asymptomatic or have very mild symptoms = 33%
  2. PPE per day per patient = 21
  3. Average duration of hospitalization in standard bed = 7
  4. Average duration in ICU bed = 9
  5. MUSC’s market share of COVID-19 patients in the Lancaster area:
    1. 35% Lancaster
    2. 15% Chester
    3. 1% Fairfield
    4. 3% Chesterfield
  6. Percent of ICU patients that will need a ventilator = 80%
  7. The following impact matrix is used for progression through illness:

Matrix model assumptions
Age % Symptomatic who are hospitalized % Admitted to ICU bed % Fatal
0 to 9 0.1% 5.0% 0.002%
10 to 19 0.3% 5.0% 0.006%
20 to 29 1.2% 5.0% 0.03%
30 to 39 3.2% 5.0% 0.08%
40 to 49 4.9% 6.3% 0.15%
50 to 59 10.2% 12.2% 0.6%
60 to 69 16.6% 27.4% 2.2%
70 to 79 24.3% 43.2% 5.1%
80+ 27.3% 70.9% 9.3%

Model results are being updated and will be available soon.