Validation protocol for multiple blood gas analyzers in accordance with laboratory accreditation programs

Ebner, Pérsio A. R.; Romano, Paschoalina; Sant’Anna, Alexandre; Mendes, Maria Elizabete; Oliveira, Magna; Sumita, Nairo M.

doi:10.5935/1676-2444.20150048

Acessibilidade / Reportar erro

Brasil

Jornal Brasileiro de Patologia e Medicina Laboratorial

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

LABORATORY MEDICINE • J. Bras. Patol. Med. Lab. 51 (5) • Sep-Oct 2015 • https://doi.org/10.5935/1676-2444.20150048 copy

Validation protocol for multiple blood gas analyzers in accordance with laboratory accreditation programs

Protocolo de validação de múltiplos equipamentos para análise de gases sanguíneos em conformidade com os programas de acreditação laboratorial

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

Introduction:

The results of blood gas analysis using different instrumentation can vary widely due to the methodological differences, the calibration procedures and the use of different configurations for each type of instrument.

Objective:

The objective of this study was to evaluate multiple analytical systems for measurement of blood gases, electrolytes and metabolites in accordance with the accreditation program (PALC) of Sociedade Brasileira de Patologia Clínica/Medicina Laboratorial (SBPC/ML).

Materials and methods:

20 samples were evaluated in three ABL800 Flex (Radiometer Medical ApS, Denmark) blood gas analyzers, and the results were compared with those of the device in use, which was considered the reference. The analysis of variance (Anova) was applied for statistical purposes, as well as the calculation of mean, standard deviation and coefficient of variation.

Results:

The p values obtained in the statistical analysis were: pH = 0.983, pO₂ = 0.991, pCO₂ = 0.353, lactate = 0.584, glucose = 0.995, ionized calcium = 0.983, sodium = 0.991, potassium = 0.926, chlorine = 0.029.

Conclusion:

The evaluation of multiple analytical systems is an essential procedure in the clinical laboratory for quality assurance and accuracy of the results.

Key words:
gas analysis; harmonization; laboratory accreditation; pH; pO₂; pCO₂; lactate; glucose; Na; K; Cl; Ca²⁺

	Intra-assay						Inter-assay
	Mean	SD	CV (%)	Mean	SD	CV (%)	Mean	SD	CV (%)	Mean	SD	CV (%)	Acceptable
Parameter	(low level)	SD	CV (%)	(high level)	SD	CV (%)	(low level)	SD	CV (%)	(high level)	SD	CV (%)	CV (%)
P^H	7.168	0.004	0.1	7.57	0.001	0	7.17	0.049	0.1	7.567	0.022	0.1	2.63
pCO₂ (mmHg)	23.5	0.48	2	63.9	0.67	1.1	23	0.56	2.4	73.9	1.3	1.8	3.6
pO₂ (mmHg)	73.4	0.38	0.5	138.7	0.49	0.4	74	0.8	1.1	137	1.3	0.9	10
Ionized calcium (mg/dl)	2.44	0.01	0.51	6.19	0.02	0.39	2.52	0.04	1.59	6.28	0.33	0.5	3.6
Sodium (mEq/l)	120	0.2	0.2	155	0.3	0.2	120	0.2	0.2	155	0.2	0.1	1.9
Potassium (mEq/l)	2.9	0.001	0.03	6.7	0.1	0.12	2.9	0.05	1.7	6.7	0.04	0.7	3.6
Chlorine (mEq/l)	74	0.8	0.8	112	0.4	0.4	74	0.7	0.9	112	0.5	0.5	2.21
Glucose (mg/dl)	107	0.9	0.8	375	0.7	0.2	112	2.2	2	391	3.7	0.9	4.88
Lactate (mg/dl)	11.3	0.5	4.8	82.4	1	1.2	11.9	0.3	2.7	81.5	1.4	1.7	20.4

	pH	pO₂	pCO₂	Ionized calcium	Sodium	Potassium	Chlorine	Lactate	Glucose
		(mmHg)	(mmHg)	(mg/dl)	(mEq/l)	(mEq/l)	(mEq/l)	(mg/dl)	(mg/dl)
Analytical sensitivity	6.87	43	14	0.41	88	1.1	66	0.6	11
Linearity	7.8	426.5	83	2.87	172	9.4	140	15.8	409
Recovery (%)	99.2	80.5	82.5	94.5	102	98.5	85.2	102.5	94.5
Stability (hours)	2	1	1	1	3	3	3	3	3

	pH	pO	pCO2	Ionized calcium	Sodium	Potassium	Chlorine	Lactate	Glucose
	pH	(mmHg)	(mmHg)	(mg/dl)	(mEq/l)	(mEq/l)	(mEq/l)	(mg/dl)	(mg/dl)
Mean high-low concentration	7.18	75.4	23.6	2.55	121	2.9	74	11.6	111
Mean low-low concentration	7.17	75.7	23.2	2.55	121	2.9	74	11.6	111
Error limit (3 SD of mean low-low concentration)	0.0075	3.5	1.8	0.05	2.1	0.1	1.3	1.6	3.9
Carryover	0.003	-0.24	0.36	-0.002	0.4	-0.02	-0.4	0	0.6

	Mean of ABL 800 Flex	Mean of the reference analyzer	Total error allowable^* * total error allowable as described by CLIA; (%)	Estimated error rate	p ^ data obtained by means of analysis of variance (Anova); CLIA: Clinical Laboratory Improvement Amendments.
pH	7.36	7.37	3.9	< ± 1	0.983
pO₂ (mmHg)	45	46	10	< ± 1	0.991
pCO₂ (mmHg)	41.9	42.6	8	< ± 1	0.353
Ionized calcium (mg/dl)	4.6	4.6	2.1	< ± 1	0.983
Sodium (mEq/l)	138	138	5	< ± 1	0.991
Potassium (mEq/l)	4.3	4.2	5.8	< ± 1	0.926
Chlorine (mEq/l)	102	104	5	< ± 1	0.029
Lactate (mg/dl)	16.5	18.4	20	< ± 1	0.584
Glucose (mg/dl)	133	136	10	< ± 1	0.985

	Interval suggested by the manufacturer	Obtained interval	Obtained mean	Obtained median	Total analyses/excluded	Verification
pH	7.35-7.45	7.35-7.45	7.4	7.41	20/0	Verified
pO₂ (mmHg)	80-100	80.6-100	91.7	91.8	20/0	Verified
pC0₂ (mmHg)	35-45	35.4-45	40.23	40.3	20/0	Verified
Ionized calcium (mg/dl)	4.49-5.29	4.54-5.2	4.79	4.74	20/0	Verified
Sodium (mEq/l)	135-145	136-143	139.17	139	20/0	Verified
Potassium (mEq/l)	3.5-4.5	3.5-4.5	3.96	3.9	20/0	Verified
Chlorine (mEq/l)	98-107	98-107	104.43	106	20/0	Verified
Lactate (mg/dl)	4-20	6-19	11.26	11.5	20/0	Verified
Glucose (mg/dl)	60-99	62-99	89.9	92	20/0	Verified

Sociedade Brasileira de Patologia Clínica, Rua Dois de Dezembro,78/909 - Catete, CEP: 22220-040v - Rio de Janeiro - RJ, Tel.: +55 21 - 3077-1400 / 3077-1408, Fax.: +55 21 - 2205-3386 - Rio de Janeiro - RJ - Brazil
E-mail: jbpml@sbpc.org.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] MAILING ADDRESS Pérsio A. R. Ebner Serviço de Bioquímica Clínica da Divisão de Laboratório Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo Laboratório de Investigação Médica; Patologia Clínica; Av. Dr. Eneas de Carvalho Aguiar, 155; CEP: 05403-000; São Paulo-SP, Brazil; Phone: +55 (11) 2661- 3385; e-mail: persio.ebner@hc.fm.usp.br.