Table 3 FMEA of the stage of delivery to spine lesions. Failures with RPN ≥ 80 or S ≥ 9 are listed

I. Call of the patient in the waiting room

1

The patient is called but a different one answers/ The patient is not called

Identification does not include patient’s name, surname, date of birth, photo-Patient was not informed of modifications regarding the time of the appointment, patient is late

Delivery of the treatment to the wrong patient -the radiotherapy treatment is not delivered or is administered late

10

1

2

20

II. Verification of the patient’s identity at the treatment’s room entry by asking personal data confirmation

2

Patient’s identity verification by checking all the personal data not performed

Only patient’s surname check

Possibility of mistaking patients and therefore treatments

10

2

3

60

X. Check of the correct view of the patient from the treatment workspace using adjustable video cameras

3

Patient is not monitored during treatment

Video cameras are not correctly oriented or functioning

Cyberknife may hit the patient without the operator noticing it. Patient may be in need and not been seen

9

2

2

36

XII. Patient selection using personal data (Name and surname)

4

Wrong patient’s name-Personal data check is not performed

Patient is called without checking patients’ list-Lapse of memory

Delivery of the treatment to the wrong patient-possibility of mistaking patients and therefore treatments

10

2

5

100

XIII. Check of the correct treatment plan and of the number of fractions as described on the report print

5

Delivery to the patient of a wrong plan-plan check not performed

Personal data and patient ID on the printed plan not checked-lapse of memory

Patient receives wrong irradiation-possibility of mistaking patients and therefore treatments

10

2

3

60

XV. Check of patient’s name, surname and medical ID by flagging the appropriate box for acceptance

6

Patient’s personal data not checked

Automatic action- Lapse of memory

Wrong patient or treatment-possibility of mistaking patients and therefore treatments

10

2

7

140

XVI. Check of: plan name, tracking method (XSight spine), path, number of fraction, collimator type and aperture-flag of the appropriate box for acceptance

7

Data check is wrong or not performed

High workload-lapse of memory

Wrong patient or treatment-possibility of mistaking patients and therefore treatments

10

2

7

140

XVII. Accurate alignment of the patient by comparing DRR and live images: adjustment of the values and tolerance levels defined in the image parameters window-adjustment of the X Sight Spine ROI dimensions

8

Wrong alignment-Threshold levels of the different parameters not modified when necessary

Difficulty to visually identify spine tract in the live images-Lapse of memory, insufficient experience of the operator with the treatment system

Treatment not properly delivered-longer time to start treatment

10

1

4

40

XIX. Setting of the most appropriate patient size

9

Appropriate patient size not set

Lapse of memory, insufficient experience of the operator with the delivery system

Possible collisions or errors of the PDP system slowing down treatment

9

2

5

90