Adeleh Nejati
Fall 2013
This project is a collaborative research project with HKS Architects in Dallas, and the main purpose of this project is to implement evidence-based knowledge to derive parameters for designing future healthcare facilities. The main objective for project 1 is to create a grasshopper model for calculating the shortest walk in order to comparing nurses walking distances in a particular bed unit design with centralized vs. decentralized nursing stations.
The Methodist Charlton Hospital in Dallas, TX, designed by HKS Architects has been selected for this project. In each bed unit, there are 36 patient rooms, 3 centralized nursing stations and 18 decentralized nursing stations. Based on literature, one nurse is usually responsible for 4-6 patients in medical-surgical units (Tevington, 2011). For the purpose of proejct 1, I defined three different scenarios and in each of them 4 patient rooms, 1 central nursing station and 2 decentralized nursing station have been selected in order to compare the walking distances for a nurse when she has to work from central station vs.decentralized station.
Dijkstra Algorithm has been implemented to calculate the shortest walk in a network of corridor routes and the main destinations from patient rooms. HKS Architects provided the data from one of their previous research project on the main destinations for nurses from patient rooms, the maximum distances and the frequency of round trips per primary shift. These data has been used in the grasshopper model in order to calculate the shortest walk for each scenario with centralized vs. decentralized nursing stations.
For more information about the Dijkstra Algorithm, please see http://en.wikipedia.org/wiki/Dijkstra%27s_algorithm and http://www.designcoding.net/shortest-path/.
The data from the grasshopper model has been analyzed in Microsoft Excel. The table and graphs below clearly shows that the having decentralized nursing stations in bed unit design may have a positive impact on reducing nurses walking distance.
Project 2: Optimizing an Inpatient Unit Design to Minimize the Nurses Walking Distance
The main objective for project 2 is to optimize an inpatient unit design in order to minimize the nurses walking distance. In the Methodist Charlton Hospital floor plan, Scenario 1 was selected to test the initial idea by creating a parametric model using genetic algorithm. In this scenario, there are a nurse station, a support area and 12 patient rooms.
The nurse station and support area are fixed spaces in the floor plan and the location of patient rooms and their distances from nurse station and support area are the variables for this model. The parametric model is created using C# Script and Galapagos components in Rhino and Grasshopper software. All the spaces in this model are defined by their center points; the x and y coordinates of patient rooms are the Genome and total distances from nurse station/support area to each room and also between patient rooms is the fitness score in the Galapagos component.
Before running the Galapagos, several restrictions are needed in this model.
- No overlapping between patient rooms.
- A minimum distance between nurse station and patient rooms.
- A minimum distance between support area and patient rooms.
All this restrictions has been implemented using C# script
component:
While running the Galapagos:
After about 5 hours, here is the result:
References
Tevington, P. (2011). Mandatory Nurse-Patient Ratios. MEDSURG Nursing: The Journal of Adult Health. 20(5), 265-168.
