(P-TA-2) Automated Red Cell Exchange – A Life Saving Measure In Methemoglobinemia, Our Centre Study

Background/Case Studies: Methemoglobinemia is life threatening condition in which diminution of the oxygen caring capacity of circulating hemoglobin occurs.
OBJECTIVE &

Aim: Two cases of methemoglobinemia where Red Blood Cell exchange (RBCX) were done as a life saving procedure since first line of treatment, methylene blue (MB) was contraindicated with a aim to improve the tissue hypoxia by replacing red cells having methemoglobin with simultaneous normal red cells infusion.

Study

Design/Methods: Case 1: Patient was 25 yrs old doctor who had P. Vivax malaria, took chloroquin for 3 days, developed weakness and breathing difficulty, shifted to ICU due to desaturation and breathing problem. On admission-pulse 140/min, B.P. 84/70 mmHg, SPO2 70 % and cyanosis was present. On investigation found to be G-6PD deficiency. RBCX done since MB was contraindicated.

Case 2: Patient with h/o high grade fever since 5 days with vomiting and oliguria having done two sittings of dialysis locally. On admission patient was tachypnic and hypoxic having cyanosis and pallor. On investigation Hb < 5 gm %, altered RFT & LFT, high methemoglobin and urine myoglobin. Since patient was having AKI, RBCX along with hemodialysis done.
METHODS: Automated red cell exchange done from central line access with the help of compatible leucodepleted red cell units. In both the cases, custom prime was done with red cells. Isovolemic exchange was targeted. Fraction of cells remaining (FCR) were aimed to keep < 50% and Hct at >30%. The whole procedures were done guarded and slowly as patients were on BiPaP and noradrenalin infusion pump.

Results/Findings: In both the cases, an immediate post procedure SPO2 was significantly improved from 64% to 90% and 70% to 92% respectively.

Conclusions: These two cases warrants for an increased awareness about RBCX as a life saving procedure in critical cases of methemoglobinemia.

Importance of research: When in the developing countries like India, an application of various therapeutic apheresis procedures for various indications are yet to be fully explore and acknowledge, our centre's study of Red Cell Exchange in relatively rare critical condition like methemoglobinemia will be exemplary for blood centres in periphery and rural district areas .