Anesthesia Risk and the Mucopolysaccharidoses: A Challenging and Changing Landscape

Abstract

The mucopolysaccharidoses (MPS) are well known to present a high risk of anesthesia. Predominantly, this risk is not only related to upper airway issues but also to multilevel airway obstruction, respiratory morbidity, and cardiac issues. Before disease-specific treatment became available, the management of the untreated patients with MPS was regarded as the worst airway problem in pediatric anesthetic practice. The last 20 to 30 years have seen great advances in the treatment of the different types of MPS with hematopoietic stem cell transplantation (HSCT) being offered to children with MPS I Hurler sundrome since the 1980s, and more recently enzyme replacement therapy (ERT) becoming available for many MPS subtypes.These treatments have undoubtedly affected the relative risk involved with an anesthetic. HSCT improves markedly the upper airway and cardiac myocardial function and there is evidence that airway management is much more straightforward. ERT, on the other hand, improves obstructive sleep apnea and exercise tolerance, but the overall effect on the risk of anesthesia is less obvious and airway complications during anesthesia remain at a high level. The impact of improved anesthetic management in the same time frame is borne out by a reduced failed intubation rate in the literature.The management of the MPS patients necessitates a multidisciplinary approach presently widely practiced in pediatric centers, but successful modes of therapy increasing their life span have pushed many of the extreme anesthetic challenges into adult practice where most anesthetists will be unfamiliar with the problem. This is a problem that needs to be addressed, and solutions to this issue could be collaborative working between pediatric and adult practitioners or an international network of experts available for advice.

Anaesthetic Management in Mucopolysaccharidoses Patients: Clinical Experience in a Tertiary Hospital

“…Besides that, these patients can also have a higher-positioned epiglottis and limited mouth opening secondary to temporomandibular joint dysplasia and micrognathia [15]. Some patients, especially those with MPS IVA [8], can also have tortuous and narrowed tracheas and tracheomalacia [3,5,7,[14][15][16][17]. Based on this evidence, a computed tomography scan of the airway with the creation of three-dimensional reconstructions of the trachea and flexible endoscopy is desirable in these patients [3,5,7,14,15].…”

“…Some patients, especially those with MPS IVA [8], can also have tortuous and narrowed tracheas and tracheomalacia [3,5,7,[14][15][16][17]. Based on this evidence, a computed tomography scan of the airway with the creation of three-dimensional reconstructions of the trachea and flexible endoscopy is desirable in these patients [3,5,7,14,15]. Skeletal dysplasia such as atlantoaxial instability, spinal cord compression mainly at the craniocervical and thoracolumbar regions, limited neck mobility, pectus carinatum, and scoliosis are features frequently found in these patients which can potentiate a difficult airway [3,5,7,10,12].…”

“…Another important aspect is the therapeutic options that are available to these patients. Recombinant human enzyme as weekly venous infusions is now available for MPS I, II, IV, and VI, and evidence shows that although the response is variable, ERT often produces significant improvement in the altered airway, by reducing soft tissue accumulation and, therefore, OSA and pulmonary complications, together with a reduction in hepatosplenomegaly, improves cosmetic and health-related quality of life (HRQoL) parameters [5][6][7][8]. HRQoL could be evaluated by addressing activities of daily living (ADL) as mobility, self-care, independence in usual activities like personal hygiene and dressing, pain and/or discomfort, anxiety, depression, energy, sleep quality, conversation, self-esteem, and school status [21].…”

“…[1][2][3][4]. Haemopoietic stem cell transplantation (HSCT) and enzyme replacement therapy (ERT) are two therapeutic strategies that can promote the improvement of airway deformities by reducing soft tissue accumulation and associated obstructive sleep apnoea (OSA) and pulmonary complications [5][6][7][8]. However, therapeutic options do not appear to significantly improve pre-existing neurocognitive dysfunction, skeletal abnormalities, or cardiac valvular dysfunction, especially if they are already advanced [5][6][7][8].…”

Hematopoietic Stem Cell Transplantation for Mucopolysaccharidoses: Past, Present, and Future

“…In 2018, Walker et al [139] reported a 14% incidence rate of airway complications patients with MPS I treated with HSCT, compared with 57% in patients with MPS I treated with ERT. Frawley et al [140] reported similar post-HSCT findings in a smaller group of patients with MPS IH.…”