A nationwide utilization survey of therapeutic drug monitoring for five antibiotics in South Korea

Figures & data

Table 1 Aspects included in the TDM survey of clinical laboratories in South Korea

Aspects	Question Items
Baseline characteristics of clinical laboratories	Types of clinical laboratories, numbers of hospital beds, and numbers of medical technologists
Implementation of drug assays	Test items, operating hours and frequency, monthly workload (number of test requests), turnaround times, internal quality control, and external quality assurance
Implementation of TDM consulting service	TDM consulting service provider (department doing TDM consulting), monthly workload (number of requests), turnaround times, and software for dosage calculation
Needs for other platform-based drug assays	Needs for point-of-care drug assays, needs for smaller scale platform drug assays, reasons for the needs for other platform-based drug assays, requirements, expectations and concerns regarding other platform-based drug assays, considerations or intentions to implement and/or use other platform-based drug assays

Abbreviation: TDM, therapeutic drug monitoring.

Table 2 Characteristics of 112 clinical laboratories in South Korea

Laboratory characteristics	Laboratories with in-house drug assays (n=62)		Laboratories without in-house drug assays (n=50)
	n	%	n	%
Type of clinical laboratories
Secondary hospitals	25	40.3	44	88.0
Tertiary hospitals	32	51.6	4	8.0
Referral laboratory	5	8.1	2	4.0
N of hospital beds
<300	1	1.6	23	41.1
300–499	2	3.2	13	23.2
500–999	36	58.1	18	32.1
1,000–1,499	12	19.4	0	0.0
1,500–1,999	3	4.8	0	0.0
>2,000	3	4.8	0	0.0
None (referral laboratory)	5	8.1	2	3.6
N of medical technologists
1–20	4	6.5	35	70.0
21–50	40	64.5	14	28.0
51–100	11	17.7	1	2.0
100–150	2	3.2	0	0.0
>150	5	8.1	0	0.0

Abbreviation: TDM, therapeutic drug monitoring.

Table 3 Current status of drug assays by 62 clinical laboratories with in-house drug assay facilities (numbers of responding laboratories)

	Vancomycin	Amikacin	Gentamicin	Tobramycin	Teicoplanin
Drug analysis operational hours
Working hours on workdays	43	7	7	5	4
24 hrs on workdays	3
24/7	15	2	1	1
Other (working hours on workdays and weekends)	1
Frequency of drug analysis for a week
<1 day		1	1	1	1
1 day					1
2 days	2				1
3 days	2
4 days	0
5 days (workdays)	35	5	5	4	1
7 days (workdays and weekends)	22	3	2	1
Other (workdays upon request only)	1
Frequency of IQC testing for drug assays
Every day, ≥1 time	55	6	5	3	2
Other (< once per day)	5	1	1	1	1
QC material for IQC
Commercialized QC materials	62	6	5	3
Others (in-house made)		1	1	1	3
Numbers of QC materials used for daily IQC
<1		1	1	1	1
1	2
2	34	2	1	1	1
≥3	25	4	4	2	1
Participation in PT provided by K-EQAS
Yes	61	6	5	4
No	1	2	2	1	4
Participation in PT provided by CAP
Yes	15	5	4	3
No	47	4	4	3	5

Abbreviations: CAP, College of American Pathologists; K-EQAS, Korean Association of External Quality Assessment Service; PT, proficiency test; IQC, internal quality control; TDM, therapeutic drug monitoring.

Figure 1 Utilization of drug assays by 112 clinical laboratories in South Korea (number of respondents). (A) Whether laboratories provide drug assay services and have in-house drug assay facilities for five antibiotics, (B) reasons for not having in-house drug assay facilities, (C) laboratories considering whether or not to provide therapeutic drug monitoring (TDM) consulting service in the future, and (D) reasons why therapeutic drug monitoring consulting services are not provided and/or will not be provided.

Table 4 Characteristics of drug assay results reporting and TDM consulting services by 62 clinical laboratories (both with and without in-house drug assay facilities, numbers of responding laboratories)

	Vancomycin	Amikacin	Gentamicin	Tobramycin	Teicoplanin
Average numbers of drug assay requests by physician per month
<50	7	41	45	39	19
≥50 and <100	14	2	1		1
≤100 and <300	28	2
≤300 and <500	8
≥500	5
Turnaround time for drug analysis
<2 hrs	15	2	1	1	1
≥2 hrs and <4 hrs	12	4	4	3
≥4 hrs and <24 hrs	32	3	3	2	2
≥24 hrs	3	36	38	33	17
Institutions providing TDM consulting service to physicians
Yes	36	10	10	7
No	26	9	8	10	16
TDM consulting service providers
Department of laboratory medicine	20	7	7	6
Department of clinical pharmacology	7	3	3	2
Department of Pharmacy	21	5	5	3
Average numbers of TDM consulting service requests by physicians per month
<50	16	8	10	7
≥50 and <100	4	2
≥100 and <300	10
≥300 and <500	2
≥500	1
Turnaround time for TDM consulting service
<4 hrs	1
4–24 hrs	23	8	7	4
≥24 hrs	8
Computer software used for TDM consulting service
Simkin CAPCIL	5	1	1
Abbott PKS	22	8	7	6
Mediware MwPharm	3	2	3	1
PKS & Mwpharm (both two programs)	2
Not available	1

Abbreviation: TDM, therapeutic drug monitoring.

Figure 2 Target concentrations for therapeutic drug monitoring of five antibiotics provided by clinical laboratories to physicians: (A) vancomycin, (B) amikacin, (C) gentamicin, (D) tobramycin, and (E) teicoplanin. The Y-axis represents target concentration (ug/mL). The X-axis represents number of respondents (laboratories). No clinical laboratories provided target peak concentrations for teicoplanin.

Figure 3 Expectations for other platform-based drug assays, such as point-of-care or smaller scale devices (number of respondents). (A) Needs for other platform-based drug assays, (B) consideration of future installation of other platform-based drug assays, and (C) reasons for needs expressed regarding other platform-based drug assays.

Figure 4 Expectations of the requirements for using other platform-based drug assays, such as (A) point-of-care and (B) smaller scale devices.

Figure 5 Concerns of the impacts of other platform-based drug assays. (A) Responses from laboratories with in-house drug assays (concerns of the impacts of point-of-care tests), (B) responses from laboratories with in-house drug assays (concerns of the impacts of smaller scale devices), (C) responses from laboratories without in-house drug assays (concerns of the impacts of point-of-care tests), and (D) responses from laboratories without in-house drug assays (concerns of the impacts of smaller scale devices).