P037: SUCCESSFUL NERVE BLOCKADE AND SEDATION IN A PATIENT WITH MUCOPOLYSACCHARIDOSIS TYPE 1 (HURLER SYNDROME) IN THE AMBULATORY SETTING
Lindsey T Webb, BSME1; April Taniguchi, BS1; Oscar J Webb, MA, MD2; 1University of Central Florida; 2Brevard Physician Associates
Hurler syndrome is a mucopolysaccharidosis type 1 (MPS 1) lysosomal storage disorder characterized by the inability to break down glycosaminoglycans. In MPS 1 disorders, a deficiency in alpha-L-iduronidase (IDUA), a lysosomal hydrolase, is inherited in an autosomal recessive manner. Due to the crucial role IDUA in heparan and dermatan sulfate degradation, storage of these glycosaminoglycans (GAGs) accumulates in the lysosome. Hurler syndrome patients can present with macroglossia, hypertrophic gums, and engorged soft tissues of the nasopharynx, which all contribute to airway obstruction. The accumulation of GAGs in lymphatic tissue further exacerbates airway reduction by causing increased tonsillar and adenoid size. The combination of airway restriction, excessive secretions, and abnormal airway anatomy make intubation and extubation more difficult. Hurler syndrome also causes dysostosis multiplex, typical skeletal abnormalities such as short stature, and short and wide clavicles. Because of the possible deposition of mucopolysaccharides in the epidural space or nerve sheath, it has been hypothesized that regional anesthesia may not be successful in these patients.
A 26-year-old, 4 ft tall male with Hurler syndrome received a proximal row carpectomy on each hand in an outpatient surgical setting, and the procedures were performed several months apart. He presented with a narrowed airway and with short clavicles, which increased the difficulty of a supraclavicular nerve blockade.
Before the procedures, an anesthesiologist evaluated the patient to determine if the anesthetics would be possible. For both carpectomies, a preoperative supraclavicular nerve blockade was performed. Because of the short length of the clavicles, the blockades were more difficult than normal. Both were successful; however, the second blockade took longer to set up and was less dense. For the blockades, the patient was given 1mg Midazolam (Versed) and 50 micro grams Fentanyl. The carpectomies were performed under sedation with solely Propofol and with no laryngeal mask airway (LMA).
A major concern for this patient was handling his airway management in the outpatient setting. The decision to use sedation without an LMA was made to prevent trauma to the airway and keep the airway open. The patient had some mask airway management during a previous carpel tunnel surgery. The decision between inpatient vs outpatient, hospital vs ambulatory, and academic vs private practice came down to anesthesia comfort and patient preference. The patient’s family requested this specific private-practice orthopedic surgeon because he had treated the patient in the past for more minor issues, and the family requested the same anesthesiologist after the first surgery. There was also concern over whether the nerve blockade would be successful because of the mucopolysaccharide buildup present in Hurler syndrome. Both blockades were successful. There was concern over the risk of seizure because of the nerve blockade, especially in the outpatient setting, which did not come to fruition.