Nitrous oxide for the treatment of psychiatric disorders: A systematic review of the clinical trial landscape.

OBJECTIVE: To systematically review published research studies and ongoing clinical trials investigating nitrous oxide (N2 O) in psychiatric disorders, providing an up-to-date snapshot of the clinical research landscape. METHODS: A comprehensive literature search was conducted for studies published until June 2021 using the OVID databases (MEDLINE, Embase, APA PsycInfo) and the clinical trial registries (ClinicalTrials.gov, ICTRP). RESULTS: In total, five relevant published articles were identified, among which four investigated N2 O for depression. One single-dose randomized controlled trial (RCT) for treatment-resistant depression (TRD), one triple crossover RCT comparing 50% vs. 25% N2 O for TRD, and one repeated-dose RCT for major depressive disorder (MDD) suggest that N2 O has preliminary feasibility with rapid-acting effects on symptoms of depression. From the public registries, 10 relevant ongoing clinical trials were identified. They aim to explore the use of N2 O for MDD, post-traumatic stress disorder, bipolar disorder, obsessive-compulsive disorder, and suicidal ideation. To date, the typical treatment protocol parameters were a single session of 50% N2 O delivered for 60 min, although the concentration of 25% is also being explored. Projected enrolment numbers for ongoing trials (M = 55.0) were much higher than sample sizes for published studies (M = 13.0), suggesting that there potentially will be more large-scale RCTs published in the next few years. CONCLUSION: Preliminary studies support the feasibility of administering N2 O for depression; however, appropriate blinding is a critical challenge. Larger-scale RCTs with repeated doses of N2 O and follow-up times beyond 1 month are needed to confirm the feasibility, therapeutic efficacy, and sustainability of response.

Stellate Ganglion Block for Psychiatric Disorders: A Systematic Review of the Clinical Research Landscape.

Stellate ganglion block (SGB) is a procedure involving the injection of a local anesthetic surrounding the stellate ganglion to inhibit sympathetic outflow. The objective of this review was to summarize existing evidence on the use of SGB in adults with psychiatric disorders. A systematic search identified 17 published studies and 4 registered clinical trials. Eighty-eight percent of published studies, including 2 randomized controlled trials (RCTs), used SGB for posttraumatic stress disorder (PTSD), although its use for schizophrenia spectrum disorders was also explored. Administration of 1 to 2 SGBs using right-sided laterality with 0.5% ropivacaine was most common. Preliminary evidence from clinical trials and case studies supports the feasibility of SGB for treating psychiatric disorders involving dysregulation of the sympathetic nervous system, although effectiveness evidence from RCTs is mixed. One RCT concluded that improvement in PTSD symptoms was significant, while the other concluded that it was nonsignificant. Improvements were noted within 5 minutes of SGB and lasted 1 month or longer. Registered clinical trials are exploring the use of SGB in new psychiatric disorders, including major depressive disorder and borderline personality disorder. More studies with larger sample sizes and alternate protocols are needed to further explore therapeutic potential of SGB for psychiatric disorders.

Facial Soft Tissue Augmentation With Bellafill: A Review of 4 Years of Clinical Experience in 212 Patients.

INTRODUCTION: Bellafill (Suneva Medical Inc) is a semipermanent injectable soft tissue filler composed of smooth and uniform polymethylmetacrylate (PMMA) microspheres suspended in a bovine collagen gel. It is a third generation PMMA filler, with more uniform shapes and sizes of the PMMA microspheres, which has been purported to decrease the incidence of granuloma formation. METHODS: We performed a retrospective review of our clinical experience from 2014 to 2017 with Bellafill as a soft tissue injectable filler in the following clinical scenarios: deep nasolabial folds, depressed facial acne scars, malar volume loss, temporal wasting, tear trough deformity, chin augmentation, angle of jaw augmentation, and lip augmentation. The primary outcome is the rate of adverse events, and the secondary outcome is subjective patient satisfaction. RESULTS: From 2014 to 2017, 842 syringes of Bellafill were administered to 212 patients, for a total of 417 procedures. Of the 417 procedures, 96 (23.0%) were for acne scars, 82 (19.7%) malar volume restorations, 65 (15.6%) nasolabial fold augmentations, 45 (10.8%) chin augmentations, 42 (10.1%) tear trough volume restorations, 28 (6.7%) temple volume restorations, 25 (6.0%) rhinoplasty touch-ups for small areas of nasal depression, 22 (5.3%) lip augmentations, and 12 (2.9%) jaw angle augmentations were performed. A range of 1 to 12 syringes were injected into each patient, over 1 to 3 sessions; 6 cases of adverse events occurred (1.4%). There were 4 cases of solitary nodules in the injection site, 1 case of lower eyelid oedema which persisted for 3 months and 1 case of lower lip oedema which resolved within hours. Patient satisfaction rates ranged from 83.3% for angle of jaw augmentation to 99.0% for improvement of acne scars. CONCLUSION: Bellafill is a safe and effective option for a semipermanent soft tissue filler, with high patient satisfaction and a good safety profile.

INTRODUCTION: Le Bellafill (Suneva Medical Inc.) est un produit de comblement injectable semi-permanent des tissus mous, composé de microsphères de polyméthymétracylate (PMMA) lisses et uniformes, suspendues dans un gel de collagène bovin. Il s'agit d'un produit de comblement de PMMA de troisième génération, dont les microsphères de PMMA, de formes et de dimensions plus uniformes, réduiraient l'incidence de granulomes. MÉTHODOLOGIE: Les chercheurs ont procédé à une analyse rétrospective de leur expérience clinique du Bellafill utilisé comme produit de comblement injectable des tissus mous dans les scénarios cliniques suivants entre 2014 et 2017: sillons nasogéniens profonds, cicatrices déprimées d'acné facial, perte de volume de l'os malaire, émaciation des tempes, dépression du rebord orbital inférieur, augmentation du menton, augmentation de l'angle des mâchoires et augmentation des lèvres. Le résultat primaire était le taux de réactions indésirables et le résultat secondaire, la satisfaction subjective des patients. RÉSULTATS: Entre 2014 et 2017, les plasticiens ont injecté 842 seringues de Bellafill à 212 patients, pour un total de 417 interventions. De ce nombre, 96 (23,0 %) visaient des cicatrices d'acné, 82 (19,7 %), la restauration du volume de l'os malaire, 65 (15,6 %), l'augmentation des sillons nasogéniens, 45 (10,8 %), l'augmentation du menton, 42 (10,1 %), la restauration du volume du rebord orbital inférieur, 28 (6,7 %), la restauration du volume des tempes, 25 (6,0 %), les retouches des petites zones de dépression nasale après une rhinoplastie, 22 (5,3 %), l'augmentation des lèvres, 12 (2,9 %), l'augmentation de l'angle de la mâchoire. Chaque patient s'est fait injecter de une à 12 seringues, réparties entre une et trois séances. Six cas de réactions indésirables se sont produits (1,4 %), soit quatre cas de nodules solitaires au point d'injection, un cas cas d'œdème de la paupière inférieure qui a persisté trois mois et un cas d'œdème de la lèvre inférieure qui a disparu en quelques heures. Le taux de satisfaction des patients a oscillé entre 83,3 % pour l'augmentation de l'angle de la mâchoire et à 99,0 % pour l'atténuation des cicatrices d'acnén. CONCLUSION: Le Bellafill est un produit de comblement des tissus mous à la fois sécuritaire et efficace, qui suscite une satisfaction élevée de la part des patients et possède un bon profil d'innocuitfi.