P.A.T.A Case Analysis

P.A.T.A Case Analysis

The Pre-Admission Testing Area (P.A.T.A.) of the Massachusetts General Hospital is a clinic dedicated to evaluating the patient’s system for tolerating and enduring anaesthesia before undergoing important surgeries.

Question 1

The P.A.T.A. clinic was facing many issues regarding patient wait-times, over hours worked by staff, lost of patient records, and early leave of the patients due to exhausting wait times. In this case, our analysis will only focus on the operational issues confronted from the patient’s point of view.

Exhibit 1 Process Flow Diagram from a Patient's Perspective

As shown in Exhibit 1, patients had to undergo a tedious process which averaged in 2.5 hours, resulting in patient build up in the chain, exceeding the capacity of the hospitals personnel resulting in extensive wait lines and overtime for the staff.

In Exhibit 2, one can view the assigned staff during normal operating hours (7:00 hrs to 12:00 hrs and 14:00 to 15:00 hrs) to keep the patients flowing in each step of the process, and in Exhibit 3 during the lunch period. (working in Annexure I)

Exhibit 2 Capacity of the P.A.T.A. process during normal operating hours with an arrival rate of 8 pat/hour

N° Step N° of Servers Time (Min/pat) Capacity Pat/hour Utilization

1 Check in 1 2 30 26.67%

2 Vitals and EKG 2 10 12 66.67%

3 Registered Nurse 5 43 6.97 114.67%

4 Anesthesiologists 8 64 7.5 93.02%

5 Blood test 3 6 30 26.67%

6 Check out 1 1 60 11.63%

Here we can see that the bottleneck of the line are Registered Nurses since they have the lowest capacity. The capacity of the line is decided by the unit with bottleneck hence the output of the line would be 7 patients per hour in regular hours and 2.8 patients per hour in lunch time. For calculating utilization, the arrival rate for the steps after the bottleneck would be decided not by patient arrival rate (8 per hour) but by the capacity of the bottleneck.

Exhibit 3 Capacity of the P.A.T.A. process during lunch break hours with an arrival rate of 4 pat/hour

Capacity

N° Step N° of Servers Time (Min/pat) Capacity Pat/hour Utilization

1 Check in 1 2 30 13.33%

2 Vitals and EKG 2 10 6 66.67%

3 Registered Nurse 2 43 2.79 143.33%

4 Anesthesiologists 4 64 3.75 74.42%

5 Blood test 2 6 20 13.95%

6 Check out 1 1 60 4.65%

Question 2

Patients who end up waiting

Time Slot Number of Hours Line Capacity Arrival Rate Patients in Queue No of patients waiting

7am - 12am 5.00 7.00 8.00 1.00 5.00

12am – 2pm 2.00 2.80 4.00 1.20 2.40

2pm – 3pm 1.00 7.00 8.00 1.00 1.00

8.40

So it will take 1.2 hours or 1 hour 12 min to clear the backlog since after 3 we have no patients arriving and capacity of the line is 7 per hour.

Patients build up each hour reaching a maximum of 9 patients at 15 hrs as depicted on the graph of Exhibit 4.

Exhibit 4 Patients waiting during different times of the day

Exhibit 5 Average Patients waiting in line due to bottleneck

Time Slot Number of Hours No of Patients At beginning No of Patients Added No of Patients At end Average patients Weighted average

7am - 12am 5 0 5 5 2.5 12.5

12am – 2pm 2 5 2.4 7.4 6.2 12.4

2pm – 3pm 1 7.4 1 8.4 7.9 7.9

3pm – 4:12pm 1.2 8.4 -8.4 0 4.2 5.04

9.2 Av Wait Line 4.11

Exhibit 6 Average Arrival Rate During the Day

Time Slot Number of Hours Arrival Rate Weighted average

`7-12 5 8 40

`12-2 2 4 8

`2-3 1 8 8

3-4:12 1.2 0 0

9.2 6.09

In order to calculate the time average time waited by the patients, an average is estimated between each hour as shown in Exhibits 5 & 6, the average waiting time is considered as the average line divided by the average arrival rate, resulting in an average waiting time of 41 minutes.

Question 3, 4 and 5

The diagnosis by the task force are partially correct. Spreading out the patient arrival time even though solves the bottleneck by reducing the arrival rate, it is not a viable solution as it decreases the number of patients that can be served in one working day. One patient takes on average 107 min (meeting with the nurse and doctor) and arrive at 8 patients per hour. We have 12 exam rooms which brings utilization of rooms to 1.20 (=8/(12*60/108)). Hence, rooms are also contributing to the waiting lines. Currently, our working suggests that nurses are the bottleneck and primary contributors to long patient wait times since their capacity is 7 patients per hour while patients arrive at a rate of 8 per hour. But even if we remove this bottleneck and make the capacity as 8, the Doctors would become the new bottleneck since their capacity is 7.5 patients per hour. Apart from these two steps which are less than arrival rate, we have other process issues - the time taken per patient at each step has a lot of variability which creates a small delay or idle time till the time another patient can be served. Also the arrival time of patients is not consistent with their appointment time. This causes periods of idle time during the start of the day and then staff has to end up working overtime to serve the rush of customers coming together. One last issue being faced here is that the capacity of the line during lunch