Tertiary Pediatric Academic Institution's Experience With Intraoperative Neuromonitoring for Nonspinal Surgery in Children With Mucopolysaccharidosis, Based on a Novel Evidence-Based Care Algorithm.

BACKGROUND: Musculoskeletal deformities in mucopolysaccharidoses (MPSs) patients pose unique challenges when patients present for surgery, especially nonspinal surgery. MPS patients have developed postsurgical neurological deficits after nonspinal surgery. While the incidence of neurological deficits after nonspinal surgery under anesthesia is unknown, accumulating evidence provides impetus to change current practice and increased neurological monitoring in these patients. Intraoperative neurophysiologic monitoring (IONM) with somatosensory evoked potentials (SSEPs) and transcranial motor evoked potentials (TcMEPs) has been implemented at select institutions with varying degree of success. This report describes our experience with IONM in the context of a multidisciplinary evidence-based care algorithm we developed at Cincinnati Children's Hospital Medical Center. METHODS: We conducted a retrospective chart review of the electronic medical record (EPIC), for data from all MPS patients at our institution undergoing nonspinal surgery between September 2016 and March 2018. Patients were identified from IONM logs, which include procedure and patient comorbidities. Data concerning demographics, morbidities, degree of kyphoscoliosis, intraoperative administered medications and vital signs, surgical procedure, the IONM data, duration of surgery, and blood loss were extracted. Descriptive analyses were generated for all variables in the data collected. In addition, any IONM changes noted during the surgeries were identified and factors contributing to the changes described. RESULTS: Thirty-eight patients with a diagnosis of MPS underwent nonspinal surgery, and of those 38, 21 received IONM based on preoperative decision-making according to our care algorithm. Of the 21 patients who received IONM, we were able to get reliable baseline potentials on all patients. Of the 21 patients, 3 had significant neurophysiologic changes necessitating surgical/anesthetic intervention. All of these changes lasted several minutes, and the real-time IONM monitoring was able to capture them as they arose. None of the patients sustained residual neurological deficits. Thus, children who did not fit the criteria for IONM (n = 13) based on our algorithm had 0% incidence of any untoward neurological deficits after surgery (97.5% confidence interval [CI], 00%-25.5%), while 14% (95% CI, 11.5%-30.1%) of children who did fit criteria for IONM and had IONM had significant IONM changes. CONCLUSIONS: Through this case series, we describe our experience with the use of IONM and a novel care algorithm for guiding the anesthetic management of MPS patients undergoing nonspinal surgery. We conclude that they can be useful tools for provision of safe anesthetic care in this high-risk cohort.

Intraoperative neurophysiological monitoring in pediatric neurosurgery.

The use of intraoperative neurophysiological monitoring (IONM) in pediatric neurosurgery is not new; however, its application to a wider range of procedures is a relatively new development. The purpose of this article is to review the physiology underlying the commonly employed IONM modalities and to describe their application to a subset of pediatric neurosurgical procedures.

How Integrated Anesthesia Communication Leads to Dependable IONM Data.

Many algorithms, checklists, and escalation pathways have been created to encourage perioperative teams to share a mental model and approach patient care as a team. Respecting and empowering the many voices involved in patient care is crucial to avoid errors and improve patient safety. None of the concepts described herein are novel; however, sustained improvements in operating room culture remain elusive in many organizations. The implementation of practices directed toward driving change in operating room culture has led to improvements in Occupational Safety and Health Administration (OSHA) recordables, perioperative communication, and patient care practices. In this paper, we will review the importance of culture, mutual accountability, and communication in improving patient care, and share several of the processes that have been created at our pediatric tertiary care center.

Suppression of calcium-induced repolarization heterogeneity as a mechanism of nitroglycerin's antiarrhythmic action.

This study examined whether the antifibrillatory action of nitroglycerin (NTG) is attributable to reduction in calcium-induced heterogeneity of repolarization independent of autonomic and coronary vasodilatory influences. The effects of intrapericardial (IPC) NTG on coronary blood flow, contractility, repolarization, and arrhythmia susceptibility were measured in anesthetized pigs (N = 43). Autonomic influences were minimized by vagotomy and beta-adrenergic blockade (metoprolol, 1.25 mg/kg, intravenous). Electrophysiological parameters were tested at 30 min, a time when coronary hemodynamics had returned to baseline. Intracoronary calcium chloride (CaCl2, 50-mg bolus) injection augmented contractility (dP/dt(max), 1760 +/- 144 to 2769 +/- 274 mmHg/s, and following NTG, 1531 +/- 384 to 2138 +/- 242 mmHg/s, P < 0.0002), reflecting increased myocardial intracellular calcium. Calcium increased repolarization heterogeneity (interlead precordial T-wave heterogeneity, 95 +/- 15 to 264 +/- 33 microV, P < 0.006; T(peak)-T(end), an index of transmural dispersion of repolarization, 37 +/- 3 to 76 +/- 6 ms, P < 0.05) and lowered repetitive extrasystole threshold (RET; 24 +/- 2 to 13 +/- 1 mA, and following NTG, 32 +/- 4 to 18 +/- 1 mA, P < 0.0001). IPC NTG raised the RET from baseline by 33% and blunted calcium-induced contractility (dP/dt(max) by 23%, P < 0.05), repolarization changes (T-wave heterogeneity by 24%, P < 0.006; T(peak)-T(end) by 18%, P = 0.04), and arrhythmia vulnerability (RET by 39%, P < 0.003). Thus, the capacity of NTG to suppress calcium-induced repolarization heterogeneity is an important mechanism of its antiarrhythmic action, which is independent of autonomic and vasodilatory actions.