Derin Beyin Stimulatörü Uygulanan Hastalarda Skalp Bloğu ve İnfiltrasyon Anestezisinde Methemoglobinemi Riski

Abstract

The application of local anesthetics in areas with a high blood supply, such as scalp block, is more susceptible to systemic effects of local anesthetics such as methemoglobinemia because of the high absorption rate and the risk of intravascular injection. In this study, we aimed to evaluate the risk of methemoglobinemia by reviewing methemoglobin values after scalp block in patients with a deep brain stimulation (DBS) due to neurological diseases, especially Parkinson's.The study included 41 patients aged >18 years who were admitted between January 2017 and December 2018 for DBS and underwent regional anesthesia (n = 41). Patients were administered scalp block (n = 10) and infiltration anesthesia (n = 31). Using data from the patients' medical records, we statistically analyzed the patients' age, American Society of Anesthesiologists (ASA) status, gender, DBS indication, scalp block/infiltration anesthesia, highest methemoglobin level in arterial blood gas, pH, pO2, SpO2, and clinical symptoms.The indications for DBS were Parkinson's disease in 29 patients hyperreactivity, dystonia and tremor in the remaining patients. Furthermore, 33 patients were classified as ASA class II. The methemoglobinemia level was >2% in two patients who underwent scalp block and six patients who underwent infiltration anesthesia. However, there was no statistically significant difference in methemoglobin levels between scalp and infiltration anesthesia.In areas with high blood flow, such as the scalp, caution should be exercised in administering local anesthesia because of the patient's risk of developing methemoglobinemia, although there are no clinical findings on this topic.