EVALUATION OF SODIUM, POTASSIUM AND HEMOGLOBIN VALUES MEASURED IN BLOOD GASES, BIOCHEMISTRY AND BLOOD COUNTING DEVICES ACCORDING TO THE TOTAL ALLOWABLE ERROR LIMITS

Öz

Objective: In our study, we aimed to calculate the 95% confidence intervals of sodium, potassium and hemoglobin values measured simultaneously in biochemistry, blood count and blood gas devices and to compare them with the total allowable error limits. Materials and Methods: Sodium, potassium and hemoglobin values of 2341 patients admitted to our hospital in September-November 2021 were analyzed retrospectively. Simultaneous results obtained from blood gas devices were compared with data obtained from biochemistry and blood counters. The sodium test was categorized as hyponatremia for values <136 mmol/L, normonatremia for values 136-145 mmol/L, and hypernatremia for values >145 mmol/L. Potassium test was grouped as hypopotassemia for values <3.5 mmol/L, normopotassemia for values 3.5-5.1 mmol/L, and hyperpotassemia for values >5.1 mmol/L. Hemoglobin test was grouped according to the values determined by the World Health Organization for men and women. For each subgroup, 95% confidence intervals were calculated according to the formula "Bias% + Z x Standard error of the mean" and compared with the total allowable error limits. Results: All levels of sodium test and only high levels of hemoglobin were found to be incompatible because the 95% confidence interval value was outside the allowable error limits. Conclusion: The obtained 95% confidence interval values showed that sodium and hemoglobin results should be evaluated according to the clinical condition of the patient. It was thought that the different results obtained were due to the analysis of the samples by different devices. It should also be kept in mind that different device results should not be compared in the follow-up of patients.

Anahtar Kelimeler

• Hemoglobin
• Electrolytes
• Blood Gas Analysis

KAN GAZLARI, BİYOKİMYA VE KAN SAYIM CİHAZLARINDA ÖLÇÜLEN SODYUM, POTASYUM VE HEMOGLOBİN DEĞERLERİNİN TOTAL İZİN VERİLEN HATA SINIRLARINA GÖRE DEĞERLENDİRİLMESİ

Öz

Giriş: Çalışmamızda biyokimya, kan sayım ve kan gazı cihazlarında eş zamanlı ölçülen sodyum, potasyum ve hemoglobin değerlerinin %95 güven aralığının hesaplanması ve toplam izin verilen hata sınırları ile karşılaştırılması amaçlandı. Gereç ve Yöntem: Hastanemize 2021 Eylül-Kasım aylarında başvuran 2341 hastanın sodyum, potasyum ve hemoglobin değerleri retrospektif olarak incelendi. Kan gazı cihazlarından eş zamanlı elde edilen sonuçlar, biyokimya ve kan sayım cihazından elde edilen veriler ile karşılaştırıldı. Sodyum testi, 136 mmol/L’nin altındaki değerleri için hiponatremi, 136-145 mmol/L değerleri için normonatremi, 145 mmol/L’nin üzerindeki değerleri için hipernatremi olacak şekilde gruplandırıldı. Potasyum testi, 3,5 mmol/L’nin altındaki değerleri için hipopotasemi, 3,5-5,1 mmol/L değerleri için normopotasemi, 5,1 mmol/L’nin üzerindeki değerleri için hiperpotasemi olacak şekilde gruplandırıldı. Hemoglobin testi ise kadın ve erkekler için Dünya Sağlık Örgütü’nün belirlediği değerlere göre gruplandırıldı. Her bir alt grup için “%Bias + Z x Ortalamanın standart hatası” formülüne göre %95 güven aralığı hesaplandı ve toplam izin verilen hata sınırları ile karşılaştırıldı. Bulgular: Sodyumun tüm düzeyleri ile hemoglobinin sadece yüksek düzeylerinin %95 güven aralığı değerleri, toplam izin verilen hata sınırları dışında bulunduğu için uyumlu olmadığı görüldü. Sonuç: Elde edilen %95 güven aralığı değerleri, sodyum ve hemoglobin sonuçlarının hastanın klinik durumuna göre değerlendirilmesi gerektiğini göstermiştir. Elde edilen farklı sonuçların numunelerin farklı cihazlarla analiz edilmesinden kaynaklandığı düşünülmüştür. Ayrıca hastaların takibinde farklı cihaz sonuçlarının karşılaştırılmaması gerektiği de unutulmamalıdır.

Anahtar Kelimeler

• Hemoglobin
• Elektrolitler
• Kan Gazı Analizi

Kaynakça

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