Rare.  The affinity for oxygen is decreased due the substitution of GTC in place of GAC on the codon 94 of the α2 chain of  hemoglobin. This mutation causes only a moderate  instability of hemoglobin , without any clinical signs except a low saturation at pulse oximetry (P50  30.5 mmHg versus 26.9 mmHg for normal hemoglobin).

Anesthetic implications:

complete blood count; falsely low pulse oximetry values at room air with poor response to an increase in  FiO2; if in doubt, make a measurement of arterial blood gases to measure PaO2.

References:

-         Hitaka D, Arai J. 
Diagnosis and clinical presentation of hemoglobin Kirksey. 
Pediatrics international 2016; 58: 235-7.

Updated: March 2019