A Spatial Memory Deficit in Male But Not Female Rats After Neonatal Diazepam Exposure: A New Model for Developmental Sedative Neurotoxicity.

BACKGROUND: Developmental anesthetic neurotoxicity is well described in animal models for GABAergic, sedating drugs. Here we investigate the role of the benzodiazepine, diazepam on spatial and recognition memory of young adult rats after neonatal exposure. METHODS: On postnatal day 7, male (n = 30) and female (n = 30) rats were exposed to diazepam (30 mg/kg intraperitoneally) or vehicle. On postnatal day 42, animals started a series of behavioral tests including Barnes maze (spatial memory), object recognition battery (recognition memory), and open field and elevated plus maze (anxiety). In a separate cohort, blood gases were obtained from diazepam-exposed animals and compared to isoflurane-exposed animals (1 MAC for 4 hours). RESULTS: Male animals exposed to diazepam had impaired performance in the Barnes maze and were unable to differentiate the goal quadrant from chance (1-sample t test; tdiazepam/male (14) = 1.49, P = .158). Female rats exposed to diazepam performed the same as the vehicle controls ( tdiazepam/female (12) = 3.4, P = .005, tvehicle/female (14) = 3.62, P = .003, tvehicle/male (13) = 4.76, P < .001). There were no statistical differences in either males or females in measures of recognition memory, anxiety, or locomotor activity in other behavioral tests. Physiologic measurements of arterial blood gases taken from animals under sedation with diazepam were much less aberrant than those exposed to the volatile anesthetic isoflurane by t test (pH diazepam [M = 7.56, standard deviation {SD} = 0.11] versus pH Isoflurane [M = 7.15, SD = 0.02], t (10) = 8.93, P < .001; Paco 2diazepam [M = 32.8 mm Hg, SD = 10.1] versus Paco 2Isoflurane [M = 91.8 mm Hg, SD = 5.8], t (10) = 8.93, P < .001). CONCLUSIONS: The spatial memory results are consistent with volatile anesthetic suggesting a model in which development of the GABA system plays a critical role in determining susceptibility to behavioral deficits.

Obstructive Sleep Apnea in Neonates.

Neonates have distinctive anatomic and physiologic features that predispose them to obstructive sleep apnea (OSA). The overall prevalence of neonatal OSA is unknown, although an increase in prevalence has been reported in neonates with craniofacial malformations, neurological disorders, and airway malformations. If remained unrecognized and untreated, neonatal OSA can lead to impaired growth and development, cardiovascular morbidity, and can even be life threatening. Polysomnography and direct visualization of the airway are essential diagnostic modalities in neonatal OSA. Treatment of neonatal OSA is based on the severity of OSA and associated co-morbidities. This may include medical and surgical interventions individualized for the affected neonate. Based on this, it is expected that infants with OSA have more significant healthcare utilization.

Implications of radiofrequency ablation in patients undergoing thyroid surgery for benign disease in the United States.

BACKGROUND: Radiofrequency ablation is an alternative strategy for the management of benign thyroid conditions. We analyzed the proportion of patients who underwent thyroid surgery for benign conditions who would be potentially eligible for radiofrequency ablation. METHODS: We identified patients who underwent thyroid surgery from 2015 to 2019 at the study institution for Bethesda II cytopathology or toxic adenoma. Patients were considered potentially eligible for radiofrequency ablation if they had a dominant nodule >2 cm with or without compression symptoms, a dominant nodule <2 cm with compression symptoms, or a toxic adenoma. RESULTS: Of 411 patients in total, 284 (69.1%) would be eligible to consider thyroid radiofrequency ablation. In the radiofrequency ablation-eligible group, 20 (7.0%) experienced voice change after surgery, and 2 (0.7%) were dissatisfied or concerned about their scar. In the radiofrequency ablation-eligible group, 70 patients (24.6%) had malignancy diagnosed by final pathology, and 23 patients (8.1%) had cancers that were equal to or larger than 1 cm in size. CONCLUSION: Many patients who undergo surgery for benign thyroid disease could be considered for radiofrequency ablation as an alternative treatment modality. Given the rate of occult malignancy, optimal evaluation of nondominant nodules before radiofrequency ablation and long-term thyroid surveillance for patients who undergo radiofrequency ablation should be further studied.

Treatment Considerations for Obstructive Sleep Apnea in Pediatric Down Syndrome.

Children with Down syndrome (DS) are at high risk for developing obstructive sleep apnea (OSA) compared to children without DS. The negative impact of OSA on health, behavior, and cognitive development in children with DS highlights the importance of timely and effective treatment. Due to the higher prevalence of craniofacial and airway abnormalities, obesity, and hypotonia in patients with DS, residual OSA can still occur after exhausting first-line options. While treatment commonly includes adenotonsillectomy (AT) and continuous positive airway pressure (CPAP) therapy, additional therapy such as medical management and/or adjuvant surgical procedures need to be considered in refractory OSA. Given the significant comorbidities secondary to untreated OSA in children with DS, such as cardiovascular and neurobehavioral consequences, more robust randomized trials in this patient population are needed to produce treatment guidelines separate from those for the general pediatric population of otherwise healthy children with OSA. Further studies are also needed to look at desensitization and optimization of CPAP use in patients with DS and OSA.