Hyperventilation Syndrome After Strabismus Surgery - A Case Report

Abstract

Hyperventilation syndrome (HVS) mainly occurs in patients under anxiety and stress and is marked by rapid, excessive breathing, resulting in respiratory alkalosis and subsequent hypocalcemia and hypokalemia, causing various physical symptoms, like numbness or tingling sensation, overactive reflexes, muscle cramps, twitches, and in severe cases, acute myocardial infarction or even death, requiring immediate diagnosis and medical intervention. We report a rare case of HVS after strabismus surgery under local anesthesia. The patient is a healthy 31-year-old woman with no psychiatric or other diseases in the past medical history. At the end of the procedure, as soon as the surgeon uncovered the sheet, the patient complained about numbness in the lower limbs, spasm in the upper limbs, muscle rigidity, and double vision. At that time, the electrocardiogram monitoring showed normal blood pressure, heart rate, pulse oxygen saturation, and breathing rate. However, the patient was awake and extremely nervous. Emergency arterial blood gas analysis (ABG) was performed immediately and revealed respiratory alkalosis with significantly reduced PaCO₂ and secondary hypocalcemia and hypokalemia. Verbal reassurance, closed-mask inhalation, and electrolyte supplement were administered. HVS gradually subsided. In this context, a prompt differential diagnosis and a high degree of suspicion are essential. Monitoring end-tidal carbon dioxide may also aid in the early detection of HVS, as changes in breathing rate and pattern may be observed before definite signs and symptoms manifest in patients with HVS. However, since surgical drapes and trays cover the torso, detecting any changes in breathing rate and pattern during the surgery may be challenging. This article describes a case of HVS after strabismus surgery under local anesthesia and provides a summary of the occurrence, manifestation, diagnosis, and treatment of HVS. It is hoped that this article will facilitate the prompt identification and appropriate treatment of HVS, thereby preventing any potential negative outcomes for the patients. Additionally, HVS is a rare complication during the perioperative period and has only been reported in a small number of case reports. Therefore, further research is needed to confirm the effectiveness of measures for prevention and treatment mentioned in the text.