Sleep-Related Breathing Disorders: When CPAP Is Not Enough

Three decades ago, continuous positive airway pressure (CPAP) was introduced to treat obstructive sleep apnea (OSA). Shortly after, bilevel positive airway pressure devices (BPAP) that independently adjusted inspiratory and expiratory positive airway pressure were developed to treat complex sleep-related breathing disorders unresponsive to CPAP. Based on the bilevel positive airway pressure platform (hardware) governed by propriety algorithms (software), advanced modes of noninvasive ventilation (NIV) were developed to address complex cardiorespiratory pathophysiology beyond OSA. This review summarizes key aspects of different bilevel PAP therapies (BPAP with/without backup rate, adaptive servoventilation, and volume-assured pressure support) to treat common sleep-related hypoventilation disorders, treatment-emergent central sleep apnea, and central sleep apnea syndromes.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-020-00955-x.Key Words: Bilevel positive airway pressure (BPAP), Adaptive servoventilation (ASV), Volume-assured pressure support (VAPS), Sleep-related hypoventilation, Treatment-emergent central apnea, Central sleep apnea     

Clermont-Ferrand versus Vectec uterine manipulator for total laparoscopic hysterectomy

Objective: To compare the operation time and performance of two uterine manipulators used for total laparoscopic hysterectomy (TLH).

Material and methods: Design: Retrospective cohort analysis. Design classification: Canadian Task Force Classification II-2. Setting: Tertiary-care university-based teaching hospital and academic affiliated private hospital. Patients: All consecutive patients who underwent for TLH between January 2014 and June 2017. All operations were performed by two expert endoscopic surgeons using one of the following uterine manipulators depending on surgeon preferences: Clermont-Ferrand (CF) or Vectec (VT) MAUT60. Patients were excluded if additional surgeries such as urogynecological procedures were performed, TLH was converted to laparotomy prior to colpotomy, and when their operation records could not be obtained. A total of 169 patients were added to final analysis. Operation time, colpotomy time and the subjective performance of manipulators such as movement of the uterus, visualization of the vaginal fornices, and maintenance of pneumoperitoneum were evaluated by watching un-edited operation videos.

Results: A total of 169 patients (83 patients in CF group; 86 patients in VT group) were included in the final analysis. Patients’ baseline characteristics were comparable between groups. Operation time and time required for colpotomy were significantly shorter in the VT group. Lateral movements of the manipulators and elevation of the uterus were better with VT compared to CF (p?=?.001 for both). Compared to the CF, VT was superior for visualization of the vaginal fornices (p?=?.004) and maintenance of pneumoperitoneum (p?<?.001). Both surgeons had perfect agreement on the performance grading of manipulators (p?<?.001, Kappa values were between 0.86–0.92). There was no difference between groups in estimated blood loss and duration of hospital stay. Reinsertion or the need to change the manipulator was not required in either group. No pelvic or vaginal abscess, cuff cellulitis, dehiscence, or hematoma formations were noted.

Conclusion: Laparoscopic hysterectomy assisted with the VT uterine manipulator is associated with shorter operation and colpotomy time. Furthermore, the movements of uterus, visualization of the vaginal fornices, and maintenance of pneumoperitoneum were significantly better with VT compared to the CF manipulator.     

Nonextraction treatment with rapid maxillary expansion and mandibular symphyseal distraction osteogenesis and vertical skeletal dimensions

OBJECTIVE: To investigate the effects of rapid maxillary expansion (RME) and mandibular symphyseal distraction osteogenesis (MSDO) on vertical dimensions of the face. MATERIALS AND METHODS: Fourteen patients, nine girls and five boys, underwent RME and MSDO procedures. Distraction was carried out at a rate of 1 mm per 24 hours with a tooth-borne appliance. The amount of distraction was 7 mm for each patient. Standardized lateral cephalograms were taken at the following time periods: before treatment (T0), after RME (T1), at the completion of MSDO (T2), and at the end of fixed orthodontic treatment (T3). The data were evaluated by using a general linear model of repeated-measures analysis of variance and paired t-tests at the 95% confidence level. RESULTS: RME significantly increased the vertical dimensions of the face and decreased the overbite (P < .001). Although the vertical parameters of the face on the lateral cephalogram decreased after MSDO, these decreasing effects were statistically insignificant just for the distances measured from the horizontal reference line to the chin points. In other words, MSDO decreased the vertical skeletal dimensions that were increased by RME, but this neutralizing effect of MSDO was not as much as the increase caused by RME. CONCLUSION: Treatment modalities (RME, MSDO, and fixed orthodontic treatment) described in this study, in total, had little effect on the vertical skeletal measurements of the face.     

Influence of previous provisional cementation on the bond strength between two definitive resin-based luting and dentin bonding agents and human dentin

This study evaluated the effect of two different types of provisional luting agents (RelyX Temp E, eugenol-based; RelyX Temp NE, eugenol-free) on the shear bond strengths between human dentin and two different resin-based luting systems (RelyXARC-Single Bond and Duo Link-One Step) after cementation with two different techniques (dual bonding and conventional technique). One hundred human molars were trimmed parallel to the original long axis, to expose flat dentin surfaces, and were divided into three groups. After related surface treatments for each specimen, the resin-based luting agent was applied in a silicone cylindrical mold (3.5 x 4 mm), placed on the bonding-agent-treated dentin surfaces and polymerized. In the control group (n = 20), the specimens were further divided into two groups (n = 10), and two different resin-based luting systems were immediately applied following the manufacturer's protocols: RelyX ARC-Single Bond (Group I C) and Duo Link-One Step (Group II C). In the provisionalization group (n = 40), the specimens were further divided into four subgroups of 10 specimens each (Group I N, I E and Group II N, II E). In Groups I N and II N, eugenol-free (RelyX NE), and in groups I E and II E, eugenol-based (RelyX E) provisional luting agents (PLA), were applied on the dentin surface. The dentin surfaces were cleaned with a flour-free pumice, and the resin-based luting systems RelyX ARC (Group I N and E) and Duo Link (Group II N and E) were applied. In the Dual bonding groups (n = 40), the specimens were divided into four subgroups of 10 specimens each (Group I ND, ED and Group II ND, ED). The specimens were treated with Single Bond (Groups I ND and ED) or One Step (Groups II ND and ED). After the dentin bonding agent treatment, RelyX Temp NE was applied to Groups I ND and II ND, and RelyX Temp E was applied to Groups I ED and II ED. The dentin surfaces were then cleaned as described in the provisionalization group, and the resin-based luting systems were applied: RelyX ARC-Single Bond (Group I ND and ED) and Duo Link-One Step (Group II ND and ED). After 1,000 thermal cycles between 5 degrees C and 55 degrees C, shear bond testing was conducted at a crosshead speed of 0.5 mm/minutes. One-way ANOVA, followed by a post hoc Tukey test (alpha = 0.05) was done. The dentin-resin-based luting system interfaces were evaluated under a scanning electron microscope. There was a significant reduction in the mean shear bond strength values of groups subjected to the provisionalization compared to the control and dual bonding technique groups (p < 0.05). The composition of provisional luting did not create a significant difference with regard to reducing shear bond strength values (p > 0.05). With regard to resin based luting systems, the shear bond strength values of the double-bond technique groups were not significantly different from the controls (p > 0.05).     

A novel immune competent murine hypertrophic scar contracture model: A tool to elucidate disease mechanism and develop new therapies

Hypertrophic scar (HSc) contraction following burn injury causes contractures. Contractures are painful and disfiguring. Current therapies are marginally effective. To study pathogenesis and develop new therapies, a murine model is needed. We have created a validated immune‐competent murine HSc model. A third‐degree burn was created on dorsum of C57BL/6 mice. Three days postburn, tissue was excised and grafted with ear skin. Graft contraction was analyzed and tissue harvested on different time points. Outcomes were compared with human condition to validate the model. To confirm graft survival, green fluorescent protein (GFP) mice were used, and histologic analysis was performed to differentiate between ear and back skin. Role of panniculus carnosus in contraction was analyzed. Cellularity was assessed with 4′,6‐diamidino‐2‐phenylindole. Collagen maturation was assessed with Picro‐sirius red. Mast cells were stained with Toluidine blue. Macrophages were detected with F4/80 immune. Vascularity was assessed with CD31 immune. RNA for contractile proteins was detected by quantitative real‐time polymerase chain reaction (qRT‐PCR). Elastic moduli of skin and scar tissue were analyzed using a microstrain analyzer. Grafts contracted to ～45% of their original size by day 14 and maintained their size. Grafting of GFP mouse skin onto wild‐type mice, and analysis of dermal thickness and hair follicle density, confirmed graft survival. Interestingly, hair follicles disappeared after grafting and regenerated in ear skin configuration by day 30. Radiological analysis revealed that panniculus carnosus doesn't contribute to contraction. Microscopic analyses showed that grafts show increase in cellularity. Granulation tissue formed after day 3. Collagen analysis revealed increases in collagen maturation over time. CD31 stain revealed increased vascularity. Macrophages and mast cells were increased. qRT‐PCR showed up‐regulation of transforming growth factor beta, alpha smooth muscle actin, and rho‐associated protein kinase 2 in HSc. Tensile testing revealed that human skin and scar tissues are tougher than mouse skin and scar tissues.