Problem: Waiting times for patients to be seen at the Champlain
Valley Physicians Hospital in Plattsburgh, New York were rated
as excessive in patient satisfaction surveys undertaken by the
hospital as part of ongoing quality assurance review. Data were
collected for patient flow for a random week in February to assess
individual variation in physician contact time, waiting time for
laboratory results, waiting time for X-ray procedures and analysis,
and waiting time both before entering an examination room and
while in an examination room. Data were obtained on all emergency
department visits for the peak month of September and for a lower
flow month of October to allow assessment of the range of variation
from highest flow to average flow.
Methods: A computer model was created using the systems
dynamics methods of mathematical computer modeling and the Stella
II software system (High Performance Systems, Hanover, New Hampshire,
1994). Equations were developed to match observationally determined
patient arrival rates for hours of the day and days of the week.
The model was tested using the existing configuration of rooms
at CVPH (2 critical care, 5 urgent care, and 12 non-urgent care
beds). The model was accepted as accurate when it matched patient
waiting times and patient turnaround times along with rates of
patients admitted and discharged for the heavy volume month of
September and the lighter volume month of October. Once the reference
data was predicted accurately by the model, changes in numbers
of rooms were made to determine what effect this would have on
waiting time and turnaround time. An assumption was maded that
an improved physical plant would improve lab and X-ray turn around
time by 30%. Random additional arrivals were included to better
mimic actual conditions. They were increased by 10% over actual
arrivals for 1994 to mimic better probable rates in 1996 when
the new emergency room would become operational. The model diagram
is presented as Appendix I and the model equations as Appendix
Table 1 shows waiting times and turnaround times for July and
October--the former a heavy month, the latter, a light month.
Minimum and maximum waits are presented. July and September are
not significantly different from each other, but statistically
shorter time intervals (indicated by "*") are found
Table 1. Waiting times and turnaround times for heavy and average months.
|Month||Critical Care||Emergency||Non-urgent||Fast Track|
|July waiting before being seen|
|September waiting before being seen|
|October wait before being seen|
When time of day and alevel of acuity was controlled for, the
variation between staff emergency department physicians were non-significant.
A tendency was observed, however, for some locum tenems physicians
to be outside the usual range of the staff physicians with both
longer or shorter turnaround times.
A level of acceptable waiting was established as 0-20 minutes
for emergency patients, 10-40 minutes for non-urgent patients,
and 20-60 minutes for fast-track patients. Currently the CVPH
emergency department has 2 critical care beds, 5 urgent care beds,
and 12 non-urgent beds.
Table 2 shows the changes in waiting time for emergency or urgent
care cases when the numbers of rooms are changed. The computer
simulation model assumes that excess critical care patients will
be triaged to urgent care beds and excess urgent care patients
will be triaged to non-urgent beds. This is observed in practice
at the emergency department.
Table 2. Changes in waiting time and turnaround time for urgent care patients based upon number of beds available.
|Number of Critical Care Rooms||Number of Urgent Care Rooms||Number of Nonurgent Care Beds||Waiting time for urgent care|
|Turnaround time for urgent care (mean)|
Table 3 shows waiting times and turnaround times for non-urgent
Table 3. Waiting times and turnaround times for non-urgent cases varying by number of rooms.
|Number of Critical Care Rooms||Number of Urgent Care Rooms||Number of Nonurgent Care Beds||Waiting time for nonurgent care||Turnaround time for non-urgent cases|
Conclusions. To accomplish the goals for waiting time and
turnaround time for the next ten years, the need is for 4 critical
care beds, 10 urgent care beds, and a combination of 24 non-urgent
care and fast-track beds.
Our review of the literature shows that managed care will not
be expected to decrease utilization for insured or Medicaid patients,
based upon studies conducted elsewhere. A telephone advice service
is one of the few interventions which has decreased utilization,
but is difficult to implement in New York, given its malpractice
climate. Such a service has shown success in Canada in reducing
emergency department utilization.
ISDC '97 CD Sponsor