Use of dual-energy computed tomography to measure skeletal-wide marrow composition and cancellous bone mineral density.

Temporal and spatial variations in bone marrow adipose tissue (MAT) can be indicative of several pathologies and confound current methods of assessing immediate changes in bone mineral remodeling. We present a novel dual-energy computed tomography (DECT) method to monitor MAT and marrow-corrected volumetric BMD (mcvBMD) throughout the body. Twenty-three cancellous skeletal sites in 20 adult female cadavers aged 40-80 years old were measured using DECT (80 and 140 kVp). vBMD was simultaneous recorded using QCT. MAT was further sampled using MRI. Thirteen lumbar vertebrae were then excised from the MRI-imaged donors and examined by microCT. After MAT correction throughout the skeleton, significant differences (p < 0.05) were found between QCT-derived vBMD and DECT-derived mcvBMD results. McvBMD was highly heterogeneous with a maximum at the posterior skull and minimum in the proximal humerus (574 and 0.7 mg/cc, respectively). BV/TV and BMC have a nearly significant correlation with mcvBMD (r = 0.545, p = 0.057 and r = 0.539, p = 0.061, respectively). MAT assessed by DECT showed a significant correlation with MRI MAT results (r = 0.881, p < 0.0001). Both DECT- and MRI-derived MAT had a significant influence on uncorrected vBMD (r = -0.86 and r = -0.818, p ≤ 0.0001, respectively). Conversely, mcvBMD had no correlation with DECT- or MRI-derived MAT (r = 0.261 and r = 0.067). DECT can be used to assess MAT while simultaneously collecting mcvBMD values at each skeletal site. MAT is heterogeneous throughout the skeleton, highly variable, and should be accounted for in longitudinal mcvBMD studies. McvBMD accurately reflects the calcified tissue in cancellous bone.

Analysis of statements in documents of gift for academic body donation programs in the United States, and recommendations for future practice.

In US anatomical gift law, the record on which a person consents to body donation after death is referred to as a document of gift (DG). Due to the lack of legal requirements around minimum information standards, enacted recommendations in the United States, and the unknown variation across extant DGs, a review of publicly-available DGs from US academic body donation programs were performed to benchmark existing statements and recommend specific foundational content for all US DGs. From 117 body donor programs identified, 93 DGs were downloaded (median length three pages, range 1-20). Statements within the DG were qualitatively categorized into 60 codes within eight themes (Communication, Eligibility, Terms of Use, Logistics, Legal References, Financials, Final Disposition, and Signatures), using existing recommendations of academics, ethicists, and professional associations to guide analysis. Of 60 codes, 12 had high disclosure rates (67%-100% of DGs included; e.g., donor personal information), 22 had moderate rates (34%-66%; e.g., discretion to decline a body), and 26 had low disclosure rates (1%-33%; e.g., testing bodies for disease). Some codes with the lowest disclosure frequency were those previously recommended as necessary. Findings highlighted substantial variation in DG statements, with a higher number of baseline disclosure statements than previously recommended. These results present an opportunity to better understand disclosures that have importance for programs and donors alike. Recommendations suggest minimum standards of informed consent practices for body donation programs in the United States. These include clarity around consent processes, consistency of language, and minimum operational standards for informed consent.

A shared decision-making tool for obstructive sleep apnea without tonsillar hypertrophy: A randomized controlled trial.

OBJECTIVES/HYPOTHESIS: Shared decision-making is a process whereby patients and clinicians jointly establish a treatment plan integrating clinical evidence and patient values and preferences. Although this approach has been successfully employed in numerous medical disciplines, often using shared decision-making tools, otolaryngologic research assessing its use is scant. Our primary objective was therefore to determine if the tools we developed reduced decisional conflict for children with obstructive sleep apnea without tonsillar hypertrophy. STUDY DESIGN: Prospective, single-blind, randomized controlled trial. METHODS: We enrolled consecutive patients meeting inclusion criteria who were referred to our multidisciplinary upper airway center. Study patients used a shared decision-making tool whereas controls did not. Measures of decisional conflict (SURE [Sure of myself, Understanding information, Risk benefit ratio, Encouragement], CollaboRATE, and the Decisional Conflict Scale [DCS]) were obtained pre- and postvisit. RESULTS: We assessed 50 families (study group = 24, controls = 26). The mean age was 8.8 ± 6.6 years, 44% were female, 86% were white, and the mean obstructive apnea-hypopnea index was 12.7 ± 15.6 events/hour. The previsit mean DCS score was similar for controls (42.7) and study patients (40.8) (P = .38). The postvisit mean DCS score for controls was 13.3 and for study patients 6.1 (P = .034). Improvement in this score was greater in the study group (P = .03). At previsit evaluation, 63% of controls and 58% of study patients were unsure about their options. Postvisit, this improved to 4.1% and 0%, respectively. CONCLUSIONS: Families counseled regarding treatment options using shared decision-making tools had significantly less decisional conflict than those who did not use these tools. These positive outcomes suggest that clinicians should consider integrating this approach into clinical practice. LEVEL OF EVIDENCE: 1b. Laryngoscope, 128:1007-1015, 2018.

Consistent head up cardiopulmonary resuscitation haemodynamics are observed across porcine and human cadaver translational models.

AIM: The objectives were: 1) replicate key elements of Head Up (HUP) cardiopulmonary resuscitation (CPR) physiology in a traditional swine model of ventricular fibrillation (VF), 2) compare HUP CPR physiology in pig cadavers (PC) to the VF model 3) develop a new human cadaver (HC) CPR model, and 4) assess HUP CPR in HC. METHODS: Nine female pigs were intubated, and anesthetized. Venous, arterial, and intracranial access were obtained. After 6 min of VF, CPR was performed for 2 min epochs as follows: Standard (S)-CPR supine (SUP), Active compression decompression (ACD) CPR + impedance threshold device (ITD-16) CPR SUP, then ACD + ITD HUP CPR. The same sequence was performed in PC 3 h later. In 9 HC, similar vascular and intracranial access were obtained and CPR performed for 1 min epochs using the same sequence as above. RESULTS: The mean cerebral perfusion pressure (CerPP, mmHg) was 14.5 ±â€¯6 for ACD + ITD SUP and 28.7 ±â€¯10 for ACD + ITD HUP (p = .007) in VF, -3.6 ±â€¯5 for ACD + ITD SUP and 7.8 ±â€¯9 for ACD + ITD HUP (p = .007) in PC, and 1.3 ±â€¯4 for ACD + ITD SUP and 11.3 ±â€¯5 for ACD + ITD HUP (p = .007) in HC. Mean systolic and diastolic intracranial pressures (ICP) (mmHg) were significantly lower in the ACD + ITD HUP group versus the ACD + ITD SUP group in all three CPR models. CONCLUSION: HUP CPR decreased ICP while increasing CerPP in pigs in VF as well as in PC and HC CPR models. This first-time demonstration of HUP CPR physiology in humans provides important implications for future resuscitation research and treatment.

Chest compliance is altered by static compression and decompression as revealed by changes in anteroposterior chest height during CPR using the ResQPUMP in a human cadaver model.

INTRODUCTION: Chest compliance plays a fundamental role in the generation of circulation during cardiopulmonary resuscitation (CPR). To study potential changes in chest compliance over time, anterior posterior (AP) chest height measurements were performed on newly deceased (never frozen) human cadavers during CPR before and after 5min of automated CPR. We tested the hypothesis that after 5min of CPR chest compliance would be significantly increased. METHODS: Static compression (30, 40, and 50kg) and decompression forces (-10, -15kg) were applied with a manual ACD-CPR device (ResQPUMP, ZOLL) before and after 5min of automated CPR. Lateral chest x-rays were obtained with multiple reference markers to assess changes in AP distance. RESULTS: In 9 cadavers, changes (mean±SD) in the AP distance (cm) during the applied forces were 2.1±1.2 for a compression force of 30kg, 2.9±1.3 for 40kg, 4.3±1.0 for 50kg, 1.0±0.8 for a decompression force of -10kg and 1.8±0.6 for -15kg. After 5min of automated CPR, AP excursion distances were significantly greater (p<0.05). AP distance increased to 3.7±1.4 for a compression force of 30kg, 4.9±1.6 for 40kg, 6.3±1.9 for 50kg, 2.3±0.9 for -10kg of lift and 2.7±1.1 for -15kg of lift. CONCLUSIONS: These data demonstrate chest compliance increases significantly over time as demonstrated by the significant increase in the measured AP distance after 5min of CPR. These findings suggest that adjustments in compression and decompression forces may be needed to optimize CPR over time.

Identification of PAC1 receptor isoform mRNAs by real-time PCR in rat suprachiasmatic nucleus.

The pituitary adenylate cyclase-activating polypeptide (PACAP) has been implicated in the photic resetting of the rodent circadian clock in the suprachiasmatic nucleus (SCN). PACAP can exert its effects via VPAC1, VPAC2 and PAC1 G-protein coupled receptors. PAC1 and VPAC2, but not VPAC1, mRNA is expressed in rat SCN. A variety of PAC1 receptor splice variants have been described showing differences in ligand binding affinity and selectivity, G-protein coupling and ability to activate signal transduction pathways. The present experiments used PCR with isoform specific primers to determine which PAC1 variants are expressed in rat SCN. The PAC1(null) isoform and a variant containing a single 28-amino acid insert in the third intracellular (IC3) loop (hop1/2) were detected. No other IC3 variants (hip, hip-hop), N-terminal variants (PAC1(short), PAC1(very short) and PAC1(3a)) or the variant differing in transmembrane II and IV (PAC1TM4) were detected in SCN obtained at any time of day. A quantitative real-time PCR assay was established which measured combined expression of the PAC1(null/hop) variants in rat SCN during a 12:12-h light:dark (L:D) cycle. There was no significant variation of PAC1 mRNA expression (PAC1(null)+PAC1(hop)) with time of day. Nor was there a significant difference in the proportion of these two variants with time of day. These results indicate that the phase-dependency of the actions of PACAP on SCN firing and circadian behaviour are not mediated by changes in the level of expression of PAC1 receptor mRNA, nor by phase-dependent expression of PAC1 receptor variants with altered ligand binding, G-protein coupling or signalling characteristics.