Postoperative Serotonin Syndrome Following Administration of Preoperative Intrapulmonary Methylene Blue and Intraoperative Granisetron: A Case Report.

BACKGROUND Methylene blue (MB), which is often used perioperatively, is a potent monoamine oxidase inhibitor that can strongly block the clearance of extracellular serotonin. Granisetron, a serotonin receptor subtype 3 (5-HT3) antagonist, is an antiemetic used to prevent or treat postoperative nausea and vomiting (PONV). Through its antagonism, granisetron can increase the extracellular serotonin concentration. Serotonin syndrome is a potentially life-threatening condition resulting from a drug reaction that affects serotonin levels. This report is of a 50-year-old woman with postoperative serotonin syndrome following co-administration of preoperative intrapulmonary methylene blue and intraoperative granisetron. CASE REPORT A 50-year-old woman with well-controlled gastroesophageal regurgitation disease presented under impression of lung cancer. She received a computed tomography (CT)-guided localization followed by video-assisted thoracic surgery under endotracheal general anesthesia. The surgery was completed uneventfully. Her postoperative course was significant for serotonin syndrome, likely triggered by co-administration of preoperative intrapulmonary MB for tumor localization and intraoperative granisetron. Other differential diagnoses were ruled out. Her management was primarily supportive, using benzodiazepine administration, and resulted in full neurologic recovery. CONCLUSIONS Intrapulmonary MB can lead to serotonin syndrome in combination with 5HT-3 antagonists when used for preoperative tumor localization. Because both MB and 5-HT3 antagonists are being widely used clinically at present, this report has highlighted that physicians, surgeons, and anesthesiologists should be aware of serotonin syndrome, its presenting features, and management, and its association with the use of methylene blue and 5-HT3 receptor antagonists, including granisetron.

Case report: The art of anesthesiology-Approaching a minor procedure in a child with MPI-CDG.

Background: Protein glycosylation plays an important role in post-translational modification, which defines a broad spectrum of protein functions. Accordingly, infants with a congenital disorder of glycosylation (CDG) can have N-glycosylation, O-glycosylation, or combined N- and O-glycosylation defects, resulting in similar but different multisystem involvement. CDGs can present notable gastrointestinal and neurologic symptoms. Both protein-losing enteropathy and hypotonia affect the decision of using anesthetics. We reported a case of MPI-CDG with protein-losing enteropathy and muscular hypotonia that underwent different anesthesia approach strategies of vascular access. Here, we highlight why intubation with sevoflurane anesthesia and sparing use of muscle relaxants is the optimal strategy for such a condition. Case presentation: A 25-month-old girl, weighing 6.6 kg and 64 cm tall, suffered chronic diarrhea, hypoalbuminemia, and hypotonia since birth. Protein-losing enteropathy due to MPI-CDG was documented by whole-exome sequencing. She underwent three sedated surgical procedures in our hospital. The sedation was administered twice by pediatricians with oral chloral hydrate, intravenous midazolam, and ketamine, to which the patient showed moderate to late recovery from sedation and irritability the following night. The most recent one was administered by an anesthesiologist, where endotracheal intubation was performed with sevoflurane as the main anesthetic. The patient regained consciousness immediately after the operation. She had no complications after all three sedation/anesthesia interventions and was discharged 7 days later, uneventful after the third general anesthesia procedure. Conclusion: We performed safe anesthetic management in a 25-month-old girl with MPI-CDG using sevoflurane under controlled ventilation. She awoke immediately after the procedure. Due to the disease entity, we suggested bypassing the intravenous route to avoid excess volume for drug administration and that muscle relaxant may not be necessary for endotracheal intubation and patient immobilization when performing procedures under general anesthesia in CDG patients.

Perioperative transient ischemic attack caused by the cessation of warfarin.

This paper describes the circumstances of a patient who had been receiving long-term warfarin treatment, but ceased it prior to surgical operation, sustained a transient ischemic heart attack post-operatively, which eventuated in delayed extubation and locked-in syndrome. For patients at low risk of perioperative bleeding, anticoagulation with oral vitamin K antagonist can probably be able to maintain the therapeutic range (INR ≤ 2.0) extreme. For patients with a high risk of bleeding, the international normalized ratio (INR) should be kept ≤ 1.5. Within this range, patients at low risk of thrombosis can discontinue warfarin treatment for 2-5 days pre-operatively; patients at high risk for thrombosis can stop warfarin but should probably be treated with intravenous or subcutaneous heparin when the INR is subtherapeutic.