Indian Journal of Anaesthesia

ORIGINAL ARTICLE
Year
: 2020  |  Volume : 64  |  Issue : 11  |  Page : 931--936

Peri-operative management of children with spinal muscular atrophy


Matthew A Halanski1, Andrew Steinfeldt2, Rewais Hanna3, Scott Hetzel3, Mary Schroth4, Bridget Muldowney2,  
1 Children's Hospital of Omaha, Omaha, NE, USA
2 Department of Anesthesia, American Family Children's Hospital, University of Wisconsin, Madison, WI, USA
3 Department of Orthopedics and Rehabilitation, American Family Children's Hospital, University of Wisconsin, Madison, WI, USA
4 Pediatrics, American Family Children's Hospital, University of Wisconsin, Madison, WI; Cure SMA, Elk Grove, IL, USA

Correspondence Address:
Rewais Hanna
University of Wisconsin School of Medicine and Public Health, 750 Highland Ave., Madison, Wisconsin 53705
USA

Abstract

Background and Aims: Current multi-disciplinary management of children with spinal muscular atrophy (SMA) often requires the surgical management of spinal deformities. We present the outcomes of our peri-operative experience around the time of their spinal surgery and share our neuromuscular perioperative protocol. Methods: A single-centre retrospective chart review was performed to evaluate all children with SMA types I and II that underwent thoracolumbar spinal deformity correction (posterior spinal fusion or growing rod insertion) from 1990 to 2015. Electronic medical records were reviewed to assess pre-operative, intraoperative, and postoperative variables. T-tests, Wilcoxon Rank Sum, Fisher's Exact tests were performed as appropriate. Results: Twelve SMA I and twenty-two SMA II patients were included. Type I patients tended to be smaller and had a higher percentage (36.4% vs 4.5%) of American Society of Anesthesiologists (ASA) class 4 patients. Preoperative total parenteral nutrition (TPN) was utilised in 75.0% of type I and 18.2% type II patients. A difficult intubation was experienced in around 25% of the patients (20.0% SMA I, 27.3% SMA II). Approximately two hours of anaesthetic time was required in addition to the actual surgical time in both types. The intensive care unit (ICU) length of stay averaged 6 (4.0-7.5) days for type I and 3 (3-5) days for type II (p = 0.144). Average post-operative length of stay was (8 (7-9) vs. 7 (6-8)) P = 1.0. Conclusion: Children with type I and II SMA have similar hospital courses. The surgical and anaesthesia team should consider perioperative TPN and NIPPV (non-invasive positive-pressure ventilation), anticipate difficult intubations, longer than usual anaesthetic times, and potentially longer ICU stays in both SMA type I and II.



How to cite this article:
Halanski MA, Steinfeldt A, Hanna R, Hetzel S, Schroth M, Muldowney B. Peri-operative management of children with spinal muscular atrophy.Indian J Anaesth 2020;64:931-936


How to cite this URL:
Halanski MA, Steinfeldt A, Hanna R, Hetzel S, Schroth M, Muldowney B. Peri-operative management of children with spinal muscular atrophy. Indian J Anaesth [serial online] 2020 [cited 2020 Nov 28 ];64:931-936
Available from: https://www.ijaweb.org/text.asp?2020/64/11/931/299681


Full Text



 Introduction



Spinal Muscular Atrophy (SMA) is a rare disease that has devastating effects on the neuromuscular system resulting in progressive weakness. This disease often leads to shortened lifespan due to progressive respiratory failure,[1],[2] especially in the most severe subtypes (Type I and II). While exciting new treatments including nusinersen934[3] are changing disease progression, many young non-ambulatory children with SMA types I and II have progressive spinal deformities requiring treatment. In addition to the introduction of disease modifying therapies, aggressive multidisciplinary medical management has drastically improved their overall survival.[2] Orthopaedic management of the spinal deformities either with spinal fusions or posterior (distraction type) growing rods may help to slow pulmonary decline.[4]

With improved survival, there will likely be increasing numbers of severely affected children that may require spinal stabilisation. These children may be cared for at institutions that are not familiar with the peri-operative care of these frail children undergoing such major surgeries. While much has been written about the orthopaedic aspects of treating these spinal deformities,[5] current literature lacks comprehensive, SMA specific, peri-operative management strategies, focusing on major surgery (such as spine surgery). Most of the previous reports are expert opinion,[6] case studies,[7],[8] combine diagnoses,[7] and focus only on the respiratory system. In this manuscript, we describe the results of our 25 year history managing spine deformity in these children, with particular focus on the most severe SMA type I and type II children, undergoing either posterior spinal fusion or limited fusion with placement of posterior distraction type spinal growing rods. We then provide a simple comprehensive checklist summarising our management strategy based on our experience and other recommendations in the literature.

 Methods



This study was approved by the Institutional Review Board at the University of Wisconsin-Madison (IRB #2017-0008). A single centre retrospective chart review was performed to include all children with SMA types I and II undergoing thoracolumbar spinal surgery including either posterior spinal fusion or growing rod insertion from July 27th 1990 to August 11th 2015. 34 total (12 SMA type I, 22 SMA type II) patients who underwent spinal surgery at our institution were identified. Children with SMA who were undergoing other surgical procedures that were not thoracolumbar spinal surgery were excluded from the study. Anaesthesia management proceeded with either intravenous (IV) propofol (21 patients) or inhalational induction with nitrous oxide and sevoflurane (13 patients). Fiberoptic bronchoscopy was most often used as mouth opening becomes limited often prohibiting the use of videolaryngoscopy (which was only used in 4 cases). Then, anaesthetic maintenance proceeded with a total IV anaesthetic with propofol and remifentanil (29 patients) or maintenance with sevoflurane (5 patients). Perioperatively, institutional practice was use of remifentanil if using a total IV anaesthetic with neuromonitoring. Neuromuscular blockade was not routinely used especially when neuromonitoring was performed. In rare cases, rocuronium or cisatricurium was used for neuromuscular blockade and reversed at the conclusion of surgery. Intraoperatively, Standard American Society of Anesthesiologists (ASA)monitors, invasive blood pressure monitoring with arterial line, and in 26 patients somatosensory evoked potentials were monitored and in 22 patients motor evoked potentials (MEP) were monitored. Additionally, fentanyl and either morphine or hydromorphone was used for post-operative pain control in 12/34 patients. Postoperatively, 16 patients received an epidural catheter with an infusion of local anaesthetic. Electronic medical records of 12 SMA I and 22 SMA II patients were reviewed to assess pre-operative, intraoperative and postoperative variables.

T-tests, Wilcoxon Rank Sum, Fisher's Exact tests were performed as appropriate. P values <0.05 were considered significant, however P values were also adjusted using the Benjamini-Hochberg adjustment to control any false discovery.

 Results



Thirty-four type I and type II SMA patients who underwent spinal surgery at our institution were identified. Twelve were SMA type I and twenty-two were SMA type II patients. Type I patients tended to be smaller and had a higher percentage (36% vs 4.5%) of ASA class 4 patients. Pre-operative total parenteral nutrition (TPN) was utilised in 75% of type I and 18% of type II patients. A difficult intubation was experienced in 20.0% SMA I and 27.3% SMA II cases. In our retrospective review, we looked for documentation of difficult intubation. No intraoperative differences were found in surgical time, estimated blood loss (EBL), or transfusion volumes. Approximately two hours of anaesthetic time was required in addition to the actual surgical time regardless of SMA type. Postoperative courses were also similar for both types with all patients initially admitted to the intensive care unit (ICU) and ICU length of stays averaged 6 (4.0-7.5) days for type I and 3 (3-5) days for type II patients (p=0.144). Average post-operative length of stay was 8 days for type I (7-9) vs. 7 days for type II (6-8)) patients. P = 1.0. Atelectasis was common post-operatively in both type I (25%) and type II (32%) patients. Only one type I and one type II patient had post-operative pneumonia. No patients in either cohort required reintubation or had respiratory failure requiring support. No perioperative deaths or conversions to permanent controlled ventilation via tracheotomy were required during the perioperative stay [Table 1].{Table 1}

 Discussion



This study demonstrates that SMA children, prior to disease modifying treatments, independent of disease type can safely be managed through very major orthopaedic surgery. Previous studies have focused on the orthopaedic outcomes of spinal surgery.[5],[7],[9],[10],[11] In many of these previous spine studies, SMA patients are combined with other conditions (Duchenne Muscular Dystrophy or Cerebral Palsy) during the analysis[5],[12],[13],[14],[15],[16] and often only SMA type II or type III children are studied.[11],[17] Some of these studies have focused on the use of non-invasive positive pressure ventilation (NIPPV) in these mixed patients,[18],[19] while others focused on the long-term pulmonary effects of spine surgery.[4],[16],[17] Other studies have focused more on the anaesthetic side of treating only SMA children. However, these are often case reports,[8],[20] studies combining different anaesthetics with different surgical procedures on all types of SMA children,[21] or focus on anaesthetics given during very minor procedures such as intra-thecal injections.[22] This manuscript is the first to concentrate on severely affected children (Types I and II evaluated separately) undergoing similar operative treatments and compare their perioperative courses. With the dearth of similar studies in the literature, it is difficult to make direct comparisons with the 'effectiveness' of our perioperative management strategy [Table 2].[23-25] However, with only two pneumonias (6%), no post-operative re-intubation or unplanned tracheostomies, and no deaths, the serious complications appear quite low. Only one patient out of the 34 was discharged home post-operatively requiring more respiratory support (continuous non-invasive positive-pressure ventilation (NIPV)) than they had on admission (nocturnal NIPV). Although study populations differ, our results appear in line or better than previous reports,[12],[26] despite our population including many more frail type I children. While around 30% of the children experienced atelectasis, this appeared independent of disease severity and consistent to other studies of patients with abnormal baseline lung function follow spine surgery.[27] However, it should be noted that the atelectasis appeared to resolve rather quickly as the average lengths of stay was one week.{Table 2}

Several interesting findings became apparent in our review. First, despite significant experience at our institution in dealing with children with SMA, an additional two hours of operating room time was required for safe anaesthetic management and neuromonitoring in addition to the actual operative time to safely anaesthetise and wake these children. This time could be longer at less experienced institutions. This knowledge may be useful for arranging Operating Room (OR) times, staff assignments, and anticipated Paediatric Intensive Care Unit (PICU) hand-offs. Possibly playing into that extra anaesthetic time is that nearly 25% of the children had difficult intubations. Pre-operative knowledge of this by screening may ensure proper equipment and experienced staff available for these cases. Finally, while not statistically significant, it was interesting that type I children typically had a longer PICU course but a very similar hospital stay, indicating that many were almost good enough for hospital discharge when transferred out of the PICU.

The limitations should be identified and discussed. Perhaps the greatest limitation to this study is that the peri-operative plan used today and presented in this manuscript was developed over the 25 year period caring for these children. Thus, children today may receive slightly different care than they did at the beginning of the review period, due to increased experience and overall knowledge in caring for these children. The authors feel that while having an exact standard protocol to follow from the start would have been ideal from methodology standpoint, the organic nature in which the protocol was developed does not negate our results. Moreover, over 25 years, the change from paper records to electronic medical records complicated the review process. The results presented perhaps represent the 'worst case scenario' as they include outcomes during our learning curve. The smaller sample size may be seen as another limitation. Whereas one of the limitations in many of the previous studies has been their heterogeneous population,[27] we chose to restrict our findings to a much more homogeneous population, with both approaches having their strengths and weaknesses. The purpose of the current study was to focus on the perioperative hospital stay associated with their spinal surgery, thus it may be seen as a limitation that we did not specifically report on the follow-up outcomes and complications associated with the orthopaedic procedures per se; however, we have previously reported on these outcomes in other studies[4],[28] and have found them to have minimal complications.

 Conclusion



In conclusion, this study demonstrates that with appropriate multi-disciplinary care, children with SMA undergoing spine surgery can be safely managed throughout the perioperative period. Children with type I and II SMA have similar hospital courses and can be surgically treated with proper perioperative management. The surgical and anaesthesia team should consider perioperative TPN and NIPPV, anticipate difficult intubations, longer anaesthetic times, and longer ICU stay in caring for these children. This data demonstrates few serious peri-operative complications in these fragile children undergoing major spinal surgery. The summary of our perioperative treatment strategy may serve as a useful reference for other centres caring for these children.

Acknowledgements

We would like to thank Sarah Sund, MT (ASCP), CCRC and Karen Patterson, PT, DPT, MS for their contributions to this work.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1M, Levy G, Garland CJ, Gray JM, O'Hagen J, De Vivo DC, et al. The changing natural history of spinal muscular atrophy type 1. Neurology 2007;69:1931-6.
2Chung BH, Wong VC, Ip P. Spinal muscular atrophy: Survival pattern and functional status. Pediatrics 2004;114:e548-53.
3Claborn MK, Stevens DL, Walker CK, Gildon BL. Nusinersen: A Treatment for spinal muscular atrophy. Ann Pharmacother 2019;53:61-9.
4Lenhart RL, Youlo S, Schroth MK, Noonan KJ, McCarthy J, Mann D, et al. Radiographic and respiratory effects of growing rods in children with spinal muscular atrophy. J Pediatr Orthop 2017;37:e500-4.
5Bentley G, Haddad F, Bull TM, Seingry D. The treatment of scoliosis in muscular dystrophy using modified Luque and Harrington-Luque instrumentation. J Bone Joint Surg Br 2001;83:22-8.
6Islander G. Anaesthesia and spinal muscle atrophy. Paediatr Anaesth 2013;23:804-16.
7Piasecki JO, Mahinpour S, Levine DB. Long-term follow-up of spinal fusion in spinal muscular atrophy. Clin Orthop Relat Res 1986;207:44-54.
8Forget P, Lois F, Pendeville P. Postoperative use of nasal intermittent positive pressure in a patient with spinal muscular atrophy type II. Acta Anaesthesiol Belg 2008;59:99-101.
9Kulkarni AH, Ambareesha M, Scoliosis and anaesthetic considerations. Indian J Anaesth 2007;51:486-95.
10Bhutia MP, Pandia MP, Rai A. Anaesthetic management of a case of Duchenne muscle dystrophy with Moyamoya disease. Indian J Anaesth 2014;58:219-21.
11Rodillo E, Marini ML, Heckmatt JZ, Dubowitz V. Scoliosis in spinal muscular atrophy: Review of 63 cases. J Child Neurol 1989;4:118-23.
12Modi HN, Suh SW, Hong JY, Cho JW, Park JH, Yang JH. Treatment and complications in flaccid neuromuscular scoliosis (Duchenne muscular dystrophy and spinal muscular atrophy) with posterior-only pedicle screw instrumentation. Eur Spine J 2010;19:384-93.
13Modi HN, Suh SW, Song HR, Fernandez HM, Yang JH. Treatment of neuromuscular scoliosis with posterior-only pedicle screw fixation. J Orthop Surg Res 2008;3:23.
14Wang CH, Finkel RS, Bertini ES, Schroth M, Simonds A, Wong B, et al. Consensus statement for standard of care in spinal muscular atrophy. J Child Neurol 2007;22:1027-49.
15Burow M, Forst R, Forst J, Hofner B, Fujak A. Perioperative complications of scoliosis surgery in patients with Duchenne muscular dystrophy and spinal muscular atrophy, focussing on wound healing disorders. Int J Neurosci 2017;127:479-85.
16Chua K, Tan CY, Chen Z, Wong HK, Lee EH, Tay SK, et al. Long-term follow-up of pulmonary function and scoliosis in patients with duchenne's muscular dystrophy and spinal muscular atrophy. J Pediatr Orthop 2016;36:63-9.
17Chong SY, Wong YQ, Hui JH, Wong HK, Ong HT, Goh DY. Pulmonary function and scoliosis in children with spinal muscular atrophy types II and III. J Paediatr Child Health 2003;39:673-6.
18Mills B, Bach JR, Zhao C, Saporito L, Sabharwal S. Posterior spinal fusion in children with flaccid neuromuscular scoliosis: The role of noninvasive positive pressure ventilatory support. J Pediatr Orthop 2013;33:488-93.
19Bach JR, Sabharwal S. High pulmonary risk scoliosis surgery: Role of noninvasive ventilation and related techniques. J Spinal Disord Tech 2005;18:527-30.
20Zolkipli Z, Sherlock M, Biggar WD, Taylor G, Hutchison JS, Peliowski A, et al. Abnormal fatty acid metabolism in spinal muscular atrophy may predispose to perioperative risks. Eur J Paediatr Neurol 2012;16:549-53.
21Graham RJ, Athiraman U, Laubach AE, Sethna NF. Anaesthesia and perioperative medical management of children with spinal muscular atrophy. Paediatr Anaesth 2009;19:1054-63.
22Bielsky AR, Fuhr PG, Parsons JA, Yaster M. A retrospective cohort study of children with spinal muscular atrophy type 2 receiving anaesthesia for intrathecal administration of nusinersen. Paediatr Anaesth 2018;28:1105-8.
23Finkel RS, Mercuri E, Meyer OH, Simonds AK, Schroth MK, Graham RJ, et al. Diagnosis and management of spinal muscular atrophy: Part 2: Pulmonary and acute care; medications, supplements and immunizations; other organ systems; and ethics. Neuromuscul Disord 2018;28:192-207.
24Bimkrant DJ, Panitch HB, Benditt JO, Boitano LJ, Carter ER, Cwik VA, et al. American College of Chest Physicians consensus statement on the respiratory and related management of patients with Duchenne muscular dystrophy undergoing anaesthesia or sedation. Chest 2007;132:1977-86.
25Blatter JA, Finder JD. Perioperative respiratory management of pediatric patients with neuromuscular disease. Paediatr Anaesth 2013;23:770-6.
26Chong HS, Moon ES, Park JO, Kim DY, Kho PA, Lee HM, et al. Value of preoperative pulmonary function test in flaccid neuromuscular scoliosis surgery. Spine 2011;36:E1391-4.
27Liang J, Qiu G, Shen J, Zhang J, Wang Y, Li S, et al. Predictive factors of postoperative pulmonary complications in scoliotic patients with moderate or severe pulmonary dysfunction. J Spinal Disord Tech 2010;23:388-92.
28Chandran S, McCarthy J, Noonan K, Mann D, Nemeth B, Guiliani T. Early treatment of scoliosis with growing rods in children with severe spinal muscular atrophy: A preliminary report. J Pediatr Orthop 2011;31:450-4.