Brittany Hagedorn presented her findings at the recent Simulation in Healthcare Dinner sponsored by SIMUL8. The original project objective was to understand the implications on inpatient floors of an overflow policy that would be used to manage post-surgery observation patients. Based on the simulation results, the scope quickly expanded to address anticipated bed capacity shortages.

1. Pre/Post OR Bed Utilization
Case Study
Brittany Hagedorn
2/29/2013

2. Agenda
I. Scenario Scope
II. Key Findings
III. Operating Alternatives

3. I. Scenario Scope
The original project objective was to understand the implications on
inpatient floors of an overflow policy that would be used to manage post-
surgery observation patients. Based on the simulation results, the scope
quickly expanded to address anticipated bed capacity shortages.

4. II. Key Findings
Original Scope Results
Based on expected patient volumes, all three scenarios resulted in concerns
about OR delays, as well as the need for additional observation beds.
Scenario Outcomes Observations to Floor
Full
2012 2017 Schedule
Patient
15,031 15,911 16,120
Volume
Days with
67% 75% 77%
Delays
Patients
6 daily 9 daily 10 daily
Delayed
# Patients
1.3 daily 2.0 daily 2.1 daily
to Floor

5. II. Key Findings
Patient Delays
By utilizing labels and a robust set of information store spreadsheets,
we were able to export patient-level detail that allowed us to conduct a
like-real-life analysis on the causes of delays.
Minutes per Delay
Patients
• Delays are not consistent across days of the week, which suggested that there were
specific scheduling issues causing delays.
• Based on an analysis of variance (ANOVA), same-day volumes for two specialties and
observation patient carry-over were determined to be the key drivers.

6. II. Key Findings
Operational Implications – Sample Day
By simulating each day individually, we were able to uncover the cause of
delays. As patients exited the OR, they utilized an increasing proportion of
the available beds, preventing new patients from being prepped for the OR.
Pre/Post Beds in Use
ORs in Use
The ORs in use has a bimodal shape because the pre/post bed shortage caused delays in
patients being prepped for their procedure. The second surge in volumes represents
delayed patients finally getting through pre-op into the OR.

7. II. Key Findings
Block Time Utilization
The statistically relevant driver of block time utilization was the ratio of
specialty-specific block time to average procedure duration.
• The mismatch between block time length and expected procedure duration was the
primary driver of low utilization.
• For example, the CVS ratio is just about 2.0, which does not leave room for an
additional case if the first scheduled case is much longer than average.

8. III. Operating Alternatives
Pre-Admission Testing
Option 1: Reclaim the 4 preadmission testing rooms for pre/post patient care.
There was a potential trade-off between the The ideal number of pre/post patient beds
number of pre/post beds and OR delays. is dependent on risk tolerance.

9. III. Operating Alternatives
Observation Patient Assignment
Option 2: Release an increased number of observation patients to an inpatient floor.
There was a potential trade-off between observation patients
transferred to an inpatient floor and expected delays.

10. Appendix

11. Assumptions
Assumption Rationale
Historical surgery durations and patient mix is an Due to the clinical nature of these values, there
accurate representation of these values in the future is no reason to expect them to change radically
Aggregation into 7 service lines (CVS, Aggregation was based on clinical judgment,
Neuro/Ortho/Spine, ENT, Gynecology, General, volume of procedures, and was validated
Urology, Other) statistically
Maximum number of add-ons per day is 10 Based on historical rates
Observation patients are sent to the floor only if there Based on logical patient flow
is another patient waiting for pre-op
No emergency cases Designed to predict performance on normal
days, not to plan for unexpected emergencies
All add-on cases are performed at the end of the Per discussion with Starla
scheduled day, and are General cases
Fully schedule any block time available, assuming Designed to test the “worst-case” scenario
plenty of demand to use capacity
Seasonality was not considered Per discussion with Starla
Patients arrive on time and are ready for surgery Simplifying assumption
within their allotted prep time

12. Detail – Block Time Utilization by OR
Yearly utilization calculated
based on 260 12-hour days
per year
• There is potential to increase OR capacity by focusing on improving utilization of:
• ORs 1-3: underutilized due to their CVS specialty
• OR 7: underutilized due to the block time being broken up between services
• OR 14: not currently scheduled to be open every day
* Note: OR9 seems to have more than 100% because the calculation is based on a 12 hour day and OR9 has Add-On cases that run past scheduling

13. Detail – Daily Volume & Utilization
• Daily case volume ranges between 47-75, with an average of 62
• Daily block time utilization ranges between 61%-84%, with an average of 75%
• Total yearly volume is approximately 16,120

14. Detail – Volume Breakdown
Average Volume by Service Line Average Volume by Patient Type
• Outpatient is the largest patient type
• General is the largest service line (driven by assumption that add-ons are general cases)
• Note: Case volume is not equivalent to hours of OR utilization

15. Key Driver – Block Time Utilization (weekly)
• Utilization calculated as
# minutes used /
# minutes in the block
• Utilization varies widely depending
on the service line and the day of
the week.
• Targets for improvement could
include CVS block length and
Thursday block arrangement

16. Operational Alternative – Family use Waiting Room
Family Remains in Pre/Post Family Stays in Waiting Room
Room during Surgery during Surgery
% Days with Delays 77% 45%
10 daily 1 daily
# Patients Delayed
(2,647 yearly) (287 yearly)
# Observation Patients 2 daily
0 yearly
to Floor 417 yearly
• Option 3: Ask family to stay in the general waiting room during surgery in order to
reclaim the pre/post room for the next patient
• Risks:
• Simulation does not account for pre/post room turnover time, which will use
up some of the recovered time and reduce the actual impact of this change
• This change would increase the need for seating in the general waiting room,
which may not have enough capacity