Outcomes of Surgical Repair of Vascular Rings and Slings in Children: A Word for the Asymptomatic

Vascular rings (VRs) are rare aortic arch anomalies that may present with a wide variety of symptoms related to esophageal and/or airway compression. We reviewed our surgical experience in both symptomatic and asymptomatic children. All children (n = 58) who underwent surgical repair of VRs or slings (mean age 27.4 ± 45.60 months; 36 males [62%]) between March 2000 and April 2020 were included. The most common anatomic variant was a right aortic arch (RAA) with aberrant left subclavian artery (ALSCA) (n = 29; 50%). Kommerell's diverticulum was present in 23 of these patients (79%). The second most common variant was a double aortic arch (n = 22; 38%), followed by pulmonary artery sling (n = 4; 6%), RAA with mirror image branching and left ligamentum arteriosum (n = 3; 5.2%), and left aortic arch (LAA) with aberrant right subclavian artery (n = 1; 1.7%). One patient had a double ring with pulmonary artery sling and RAA with ALSCA. Symptoms were present in 42 patients (72%). Left lateral thoracotomy was the approach in 50 patients (86%), while sternotomy was used in 8 (14%). Symptomatic improvement occurred in the majority of symptomatic patients (93%). There was one perioperative mortality (1.7%) in the symptomatic group which was non-VR related. Morbidities included recurrent laryngeal nerve injury in three patients (5.2%) and transient chylothorax in two (3.4%). Persistence/recurrence of symptoms resulted in one early and one late reoperation. The mean follow-up was 3 ± 5 years. In the current era, VR repair in children including asymptomatic ones can be performed with excellent results. We recommend complete repair of RAA with aberrant LSCA by resection of Kommerell's diverticulum and translocation of the ALSCA to avoid recurrence.

Anesthetic management of pediatric patients diagnosed with X-linked adrenoleukodystrophy: A single-center experience

BACKGROUND

X-linked adrenoleukodystrophy is a progressive demyelinating disease that primarily affects males with an incidence of 1:20 000-30 000. The disease has a wide spectrum of phenotypic expression and may include adrenal insufficiency, cerebral X-linked adrenoleukodystrophy and adrenomyeloneuropathy. The condition has implications for the administration of anesthesia and reports of anesthetic management in those patients are limited at this point.

AIM

To review the perioperative care, complications and outcomes of patients diagnosed with X-linked adrenoleukodystrophy at the University of Minnesota Masonic Children's Hospital.

METHOD

After obtaining IRB approval, we performed a retrospective chart review of pediatric patients diagnosed with X-linked adrenoleukodystrophy who underwent either surgery or diagnostic/therapeutic procedures that included anesthesia services between January 2014 and December 2016. Data included demographics, American Society of Anesthesiologists classification, preoperative diagnosis, history of hematopoietic stem cell transplant, anesthetic approaches, airway management, medications used, intra- and postoperative complications, and patient disposition.

RESULTS

We identified 38 patients who had a total of 166 anesthetic encounters. The majority of patients underwent procedures in the sedation unit (75.9%) and received a total intravenous anesthetic with spontaneous ventilation via a natural airway (86.1%). Preoperative adrenal insufficiency was documented in 87.3% of the encounters. Stress-dose steroids were administered in 70.5% of the performed anesthetics. A variety of anesthetic agents were successfully used including sevoflurane, isoflurane, propofol, midazolam, ketamine, and dexmedetomidine. There were few perioperative complications noted (6.6%) and the majority were of low severity. No anesthesia-related mortality was observed.

CONCLUSIONS

With the availability of skilled pediatric anesthesia care, children with X-linked adrenoleukodystrophy can undergo procedures under anesthesia in sedation units and regular operating rooms with low overall anesthesia risk.

HeartMate III as a Bridge to Transplantation in an Adolescent With Failed Fontan Circulation

HeartMate III is an emerging, small-sized centrifugal ventricular assist device. Its lower pump thrombosis and stroke rates make it favorable for use in pediatrics. We report the use of HeartMate III as a bridge to transplantation in an adolescent with failed Fontan circulation. (Level of Difficulty: Advanced.).

Management and Anesthetic Considerations for Patients With Anomalous Aortic Origin of a Coronary Artery

The term "coronary artery anomalies" encompasses a large and heterogeneous group of disorders that may affect origin, intrinsic anatomy, course, location, and termination of the coronary arteries. With these different anatomies, presentation, symptoms, and outcomes are heterogeneous as well. While significant efforts are directed toward improving diagnosis and risk-stratification, best evidence-guided practices remain in evolution. Data about anesthetic management of patients with coronary anomalies are lacking as well. This review aims to provide the anesthesiologist with a better understanding of an important subgroup of coronary artery anomalies: anomalous aortic origin of a coronary artery. We will discuss classification, pathophysiology, incidence, evaluation, management, and anesthetic implications of this potentially fatal disease group.

Long-term effects of botulinum toxin on neuromuscular function

BACKGROUND

Recent reports indicate increased incidence of Clostridium botulinum infections, particularly among drug abusers and tissue allograft recipients. Botulinum toxin also has potential application in biochemical warfare. The neurotoxin-induced paralysis often requires mechanical ventilation with and without muscle relaxants. The authors investigated the long-term effects of botulinum toxin on muscle function, expression of nicotinic acetylcholine receptors (nAChRs), and their interaction with muscle relaxant, atracurium.

METHODS

Rats (n=30) were injected with varying doses (0.625, 2.5, and 10 U) of botulinum toxin into the tibialis muscle. Control animals (n=9) received an equivalent volume of saline. At 128 days after injection, neuromuscular function, pharmacodynamics of atracurium, and nAChRs were evaluated.

RESULTS

Nerve-evoked tensions, including tetanic tension and muscle mass, were decreased on the toxin-injected side in a dose-dependent manner relative to saline-injected controls as well as the contralateral side. Specific muscle tension and specific tetanic muscle tension (tensions/muscle mass) were not reduced. The ED10 of atracurium was reduced, the ED50 was unchanged, and the ED90 was increased in the highest (10-U) dose of toxin group. The atracurium plasma concentration to maintain a steady state 50% paralysis was significantly reduced in the 10-U toxin group. The nAChR concentrations in the tibialis muscle were significantly increased in a dose-dependent manner in all experimental groups.

CONCLUSION

Botulinum toxin causes dose-dependent long-term neuromuscular changes. The loss of tension generating capacity is almost exclusively related to muscle atrophy, because the specific tension did not change. The decreased ED10, unaltered ED50, and increased ED90 to atracurium suggest its interactions with different isoforms of receptors having varying sensitivity to atracurium. The absence of fade, despite the persistent botulinum toxin-induced denervation (increased nAChRs), suggests that the up-regulated nAChRs may have compensated for the prejunctional effects of botulinum toxin.

Succinylcholine-induced hyperkalemia in acquired pathologic states: etiologic factors and molecular mechanisms

Lethal hyperkalemic response to succinylcholine continues to be reported, but the molecular mechanisms for the hyperkalemia have not been completely elucidated. In the normal innervated mature muscle, the acetylcholine receptors (AChRs) are located only in the junctional area. In certain pathologic states, including upper or lower motor denervation, chemical denervation by muscle relaxants, drugs, or toxins, immobilization, infection, direct muscle trauma, muscle tumor, or muscle inflammation, and/or burn injury, there is up-regulation (increase) of AChRs spreading throughout the muscle membrane, with the additional expression of two new isoforms of AChRs. The depolarization of these AChRs that are spread throughout the muscle membrane by succinylcholine and its metabolites leads to potassium efflux from the muscle, leading to hyperkalemia. The nicotinic (neuronal) alpha7 acetylcholine receptors, recently described to be expressed in muscle also, can be depolarized not only by acetylcholine and succinylcholine but also by choline, persistently, and possibly play a critical role in the hyperkalemic response to succinylcholine in patients with up-regulated AChRs.