As a step of the implementation of a system for follow-up of patients undergoing high dose interventional procedures,
a survey was performed to study the frequency of occurrence of patients exceeding the proposed trigger levels.
Every patient exceeding a defined dose was asked to contact the interventionalists in case of reddening or itching on the skin.
Such a proactive mechanism in place to call or contact patient at about 1 week to 6 months after high exposure to rule out injury,
could discover most of the skin injuries and they would be diagnosed in time and adequately treated.
Our experience showed that keeping dose records in the interventional cardiology departments was not enough.
According to the recently issued trigger levels,
the interventionalists were asked to follow-up a patient within the period of 1 week to 6 months after the procedure,
if any of the parameters below exceed the indicated level:
· fluoroscopy time above 60 minutes;
· KAP above 500 Gy.cm2;
· CAK above 5 Gy;
· number of acquired series above 20;
if more than one procedure is performed on the same patient within 2 months.
A system in place was proposed to systematically monitor patient doses and to follow-up the patients with higher doses with potential for skin injury in four different hospitals.
Table 1.
No |
Date |
W,
kg
|
BMI |
KAP,
cGy.cm2
|
Cum.
dose,
mGy
|
Fluoro
time,
min
|
Diabetes
|
Prev.
PCI same vessel
|
Prev.
PCI other vessel
|
Prev.
CABG
|
CTO
|
Success of FGI
|
No of
affected vessels
|
Signs of rad.
induced
effects
(<24h)
|
Signs of rad.
induced effects
(1-4w)
|
Final signs of rad.
ind.
effects
|
Hospital A |
1 |
30.8.16 |
- |
- |
41110 |
6427 |
- |
yes |
no |
no |
no |
no |
yes |
1 |
no |
no |
no |
2 |
21.7.16 |
120 |
37.87 |
49021.5 |
7554 |
40.07 |
yes |
no |
no |
yes |
no |
yes |
3 |
no |
no |
no |
3 |
04.8.16 |
95 |
29.32 |
41195.8 |
|
55.07 |
no |
no |
no |
no |
yes |
no |
1 |
no |
no |
no |
4 |
07.7.16 |
85 |
26.23 |
27989.7 |
|
44.14 |
no |
no |
yes |
no |
yes |
no |
3 |
no |
no |
no |
5 |
27.9.16 |
70 |
27.34 |
34761.4 |
|
55.51 |
yes |
yes |
no |
no |
yes |
yes |
1 |
no |
no |
no |
6 |
06.7.16 |
93 |
30.72 |
59862 |
10960 |
88.25 |
no |
no |
yes |
no |
yes |
yes |
2 |
no |
no |
no |
7 |
15.9.16 |
95 |
34.89 |
45450.7 |
|
60.32 |
yes |
yes |
no |
no |
yes |
yes |
1 |
no |
no |
no |
8 |
13.9.16 |
120 |
34.32 |
43264.6 |
7569 |
50.57 |
yes |
yes |
no |
no |
yes |
yes |
1 |
no |
no |
no |
9 |
6.10.16 |
115 |
33.6 |
46595.7 |
|
55.16 |
yes |
no |
yes |
yes |
yes |
no |
3 |
no |
no |
no |
Hopsital B |
1 |
20.01.17 |
- |
- |
72824 |
- |
66 |
- |
- |
- |
no |
yes |
no |
- |
no |
no |
no |
2 |
12.01.17 |
- |
- |
56993 |
- |
42 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
3 |
14.11.16 |
- |
- |
79439 |
- |
94 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
4 |
02.12.16 |
- |
- |
68144 |
- |
57 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
5 |
01.11.16 |
- |
- |
67933 |
- |
68 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
6 |
22.08.16 |
- |
- |
3286 |
- |
110 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
7 |
07.11.16 |
- |
- |
- |
- |
100 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
8 |
19.10.16 |
- |
- |
79439 |
- |
94 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
9 |
26.10.16 |
- |
- |
899 |
- |
70 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
10 |
17.08.16 |
- |
- |
45545 |
- |
69 |
- |
- |
- |
no |
no |
no |
- |
no |
no |
no |
11 |
29.08.16 |
- |
- |
- |
- |
69 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
12 |
03.10.16 |
- |
- |
67933 |
- |
68 |
- |
- |
- |
no |
no |
yes |
- |
no |
no |
no |
13 |
20.01.17 |
- |
- |
72824 |
- |
66 |
- |
- |
- |
no |
yes |
no |
- |
no |
no |
no |
Hospital C
36 patients exceeding at least one of the triggger levels.
KAP,
cGy.cm2: median-48234,
range (22668-115063)
Cum.
dose,
mGy: median-6796,
range (5111-16573)
Fluoro time,
min: median-57.8 range (6.2-99)
No vailable data for radiation-induces skin injuries.
|
Hospital D |
1 |
- |
- |
- |
89075.4 |
11408 |
44.9 |
- |
- |
- |
- |
- |
- |
- |
no available data |
For the purposes for estimation of the likelihood and the severity of eventual future patient radiation effects all considerations of demographic factors,
medical history factors,
and procedure factors were studied.
It is of great importance in cases with relatively high radiation dose.
Part of the analysed data is shown in table 1.
In department A,
where the system for follow-up of patients undergoing high dose interventional procedures is fully implemented,
there are 3 main periods for visual observation for signs of radiation-induced skin injuries: first 24 hours,
1-4 weeks and 1-6 months after the procedure.
In the first 24 hours following the high dose interventional procedure,
the observation should be done by caregivers and responsible healthcare professionals who are made aware of the possible signs and symptoms for radiation-induced effects.
A patient who receives a significant radiation dose is given written instructions for follow-up of possible radiation-induced effects.
During the next two periods the observation for signs and symptoms can be done by telephone and a clinic visit only if the patient reports skin changes at the irradiated entrance skin area.
All involved “observers” are instructed to notify the operator (the interventional cardiologist) and the medical physicist of the results of examination of the irradiated area – negative or positive.
The survey showed that the frequency of occurrence of high dose FGI procedures is less than 1.3 % of all FGI procedures in hospital A,
about 1 % in hospital B,
about 7 % in hospital C. The percentage in hospital D is unknown because of a missing data about the total number of performed procedures,
but it is expected to be less than 1 %,
according to the only 1 patient exceeding at least one trigger level for the surveyed period. Most of the cases where the trigger levels are exceeded are either obese patients or procedures of higher degree of complexity.