GSTM1 and hyperinsulinemic hypoglycemia, familial, 4: In terms of hematological parameters, namely Hb and Hct, no significant changes in preoperative and postoperative deficiency were identified [Hb two cases (4.3%) vs. four cases (8.7%), p = 0.62, and Hct two cases (4.3%) vs. six cases (13.0%), p = 0.13].