F1. Introduction
(1) Reduced hemoglobin (deoxyhemoglobin)이나 hemoglobin derivatives의 증가로 인해
피부나 점막이 푸르게 변하는 것을 말함.
(2) 혈액 내 deoxygenated hemoglobin 절대량에 의해 결정 (oxygenated hemoglobin 아님)
(3) Central cyanosis, peripheral cyanosis로 구분됨.
① Central cyanosis
: 부적절한 oxygenation 또는 비정상적인 Hb에 의해 점막이나 혀에 cyanosis 발생
② Peripheral cyanosis
: Vasoconstriction이나 peripheral blood flow의 감소로 인해 발생한 손가락 내지 말초에 발생하는 cyanosis
F2. Differential Diagnosis of Cyanosis
F3. Clinical features
(1) Cyanosis : deoxygenated Hb exceeds 5 grams/dL
(2) Tongue and buccal mucosa : central cyanosis에 sensitive sites
(3) Peripheral cyanosis : CHF, peripheral vascular disease, shock states, and cold exposure
① Vasoconstriction and decreased peripheral blood flow
② The nail beds : cyanosis
(4) Pseudocyanosis
① Drug (chlorpromazine, minocycline, amiodarone, nicorandil) or heavy metal (gold, silver)
의한 피부 변색
② 입술과 점막은 정상적인 색이다.
F4. Diagnosis
(1) ABGA using co-oxymetry : gold standard
(2) Central cyanosis : SaO2 decreased
(3) Peripheral cyanosis : SaO2 normal
(4) MetHb or COHb 인 경우
① Normal PaO2, a normal calculated SaO2
② Measured SaO2 decreased
F5. Treatment
(1) Supplemental oxygen & underlying disorder treatment
(2) Methemoglobinemia
→ Methylene blue (antidote) : 1~2 mg/kg, IV over 5 min
