Mean VT Research Articles

What CPAP to use in the delivery room? Bench comparison of two methods to provide continuous positive airways pressure in neonates

BackgroundContinuous positive airway pressure (CPAP) is a recommended first-line therapy for infants with respiratory distress at birth. Resuscitation devices incorporating CPAP delivery can have significantly different imposed resistances affecting airway...

Compositional effects on etching of fossil confined fission tracks in apatite

Abstract Fission-track analysis is a thermochronologic method for dating rocks and reconstructing their low-temperature thermal histories. We investigate the influence of the apatite composition on the etching of fossil confined fission tracks, and its consequences for the fission-track method. We conducted step-etch experiments with 5.5 M HNO3 at 21 °C on samples with etch pit diameters (Dpar) spanning most of the range for natural apatites (Panasqueira: 1.60 µm, Slyudyanka: 2.44 µm, Brazil: 3.92 µm, and Bamble: 4.60 µm) to determine their apatite etch rates vR (the rate at which each lattice plane is displaced parallel to itself) as a function of crystallographic orientation (ϕ’). Our measurements revealed significant differences between the four samples. We fitted three-parameter functions, vR = a(Dpar) ϕ’ eb(Dpar)ϕ’ + c, describing vR as a function of the angle to the apatite c-axis for our hexagonal samples (excluding Bamble) and Durango apatite. The parameters a and b both exhibit a linear correlation with Dpar, whereas the constant c is small (~0.1 µm.min-1) and its between-sample variation negligible at the resolution of our measurements. Bamble exhibits a different, bimodal relationship between vR and ϕ’, which we fitted with a sum of two sine functions. In all cases, including Bamble, there is a striking correlation between the angular frequencies of horizontal confined tracks and the magnitude of the apatite etch rate vR perpendicular to the track axes. This shows that the sample of confined tracks selected for measurement and modeling is to a much greater degree determined by the etching properties of the apatite sample than by geometric or subjective biases. The track etch rate vT is constant along most of the track length but varies from track to track. The mean vT correlates with Dpar, so that tracks etch to their full lengths in a shorter time in faster etching apatites. The mean rate of length increase between etch steps, vL, also correlates with Dpar. The length increments of individual tracks are however irregular. This points to an intermittent structure at the ends of the tracks.

Prediction of protective lung tidal volume using the ulna length in Egyptian adults

Background Ventilation with low tidal volume (VT) is advised for critically ill patients to protect against ventilator-induced lung injury and provide better clinical outcomes. Previous studies showed poor compliance with using height to predict VT. Ulna length has been used successfully to predict protective low VT. Our study aims to evaluate the ability of ulna length measurement to predict accurate protective lung VT in Egyptian people in reference to their standing height. Methods This study included healthy adult volunteers aged greater than or equal to 18 years. The height of each patient was measured while standing upright against a wall. Then, the left ulna was measured with a measuring tape from the olecranon to the mid-point of the styloid process. From ulna length, height was estimated, and protective lung VT was calculated using predicted body weight (PBW). Results Total 102 participants were enrolled in this study. The agreement between the calculated VT from standing height and ulna length was analyzed with Bland Altman analysis and showed a bias of (-5.7) ml, and limits of agreements (±1.96 SD) −91 ml to 76 ml in females; when the calculated VT of ulna length was compared with predicted body weight from height, the predicted mean VT was 6.2 ml/kg (95% confidence interval CI 4.5-7.8 ml/kg). In males, using ulna length, the predicted mean VT was 6.1 ml/kg (95% CI 4.8-7.4 ml/kg). Conclusion Ulna length can be used to predict protective lung VT in Egyptian people compared with their standing height.

PO-03-094 IMAGE INTEGRATION IN VENTRICULAR TACHYCARDIA (VT) ABLATION USING SENSE2 PROTOCOL MAPPING

We have previously developed the sense protocol functional substrate mapping technique for VT ablation. This involves targeting areas of decremental signal delay during single extra pacing at short coupling interval. However, functional substrate characterization can involve protracted mapping time. We incorporated the MRI and CT data using ADAS-3D software into the mapping workflow to integrate structural mapping information into the functional mapping substrate characterization to improve procedural efficiency. Cardiac MRI/CTs were performed on 33 patients with ischemia-related VT (group A). These were processed with the ADAS-3D software to characterize the extent of ventricular scars. Focused substrate maps were then performed in patients, guided by the extent of ADAS scar and corridors, looking at the scar substrate in intrinsic rhythm and then functional channels using single extra pacing from the RV apex. Following the delineation of functional channels pace mapping and entrainment mapping were used to confirm targets for ablation. Group A was then compared to a matched cohort who underwent sense protocol mapping without MRI (group B) and an institutional cohort who underwent conventional mapping and ablation using entrainment or pace mapping (group C). 33 patients (mean age 68 years; 31 male subjects, mean EF 32%) underwent ablation. Median procedure time was 175 minutes compared with 305 and 246 minutes in groups B and C(p=<0.001) Mean substrate mapping time was 17 mins vs 80 and 63 mins in groups B and C (p=<0.001). 85% of patients were free from symptomatic VT/ anti-tachycardia pacing or implantable cardioverter defibrillator shocks at a median follow-up of 171 days. The mean VT burden was reduced from 22 events per patient in the six months pre-ablation to 1 event per patient in the median follow-up period of 171 days post-ablation (p=0.02). Sense2 protocol showed a reduced probability of device therapy compared with institutional and sense protocol (Log-rank p=0024 in the figure). The Sense2 protocol integrated structural MRI findings into functional signal ablation of VT. It shortened procedure times by enabling focused substrate maps to be performed without requiring complete geometry. Outcomes compare favourably with our previous data from sense protocol but with significantly shorter procedure times. There were improved outcomes compared to our institutional standard ablation cohort.

Driving Pressure, Elastance, and Outcomes in a Real-World Setting: A Bi-Center Analysis of Electronic Health Record Data.

Observational cohort study. Fourteen ICUs in two quaternary academic medical centers. Adult patients who received mechanical ventilation for more than 48 hours and less than 30 days. None. EHR data from 4,233 ventilated patients from 2016 to 2018 were extracted, harmonized, and merged. A minority of the analytic cohort (37%) experienced a Pao2/Fio2 of less than 300. A time-weighted mean exposure was calculated for ventilatory variables including tidal volume (VT), plateau pressures (PPLAT), DP, and ERS. Lung-protective ventilation adherence was high (94% with VT < 8.5 mL/kg, time-weighted mean VT = 6. 8 mL/kg, 88% with PPLAT ≤ 30 cm H2O). Although time-weighted mean DP (12.2 cm H2O) and ERS (1.9 cm H2O/[mL/kg]) were modest, 29% and 39% of the cohort experienced a DP greater than 15 cm H2O or an ERS greater than 2 cm H2O/(mL/kg), respectively. Regression modeling with adjustment for relevant covariates determined that exposure to time-weighted mean DP (> 15 cm H2O) was associated with increased adjusted risk of mortality and reduced adjusted ventilator-free days independent of adherence to lung-protective ventilation. Similarly, exposure to time-weighted mean ERS greater than 2 cm H2O/(mL/kg) was associated with increased adjusted risk of mortality. Elevated DP and ERS are associated with increased risk of mortality among ventilated patients independent of severity of illness or oxygenation impairment. EHR data can enable assessment of time-weighted ventilator variables and their association with clinical outcomes in a multicenter real-world setting.

Intermediate tidal volume is an acceptable option for ventilated patients with acute respiratory distress syndrome

ObjectiveEvidence only proves low surpasses high tidal volume (VT) for acute respiratory distress syndrome (ARDS). Intermediate VT is a common setting for ARDS patients and has been demonstrated as effective as low VT in non-ARDS patients. The effectiveness of intermediate VT in ARDS has not been studied and is the objective of this study. DesignA retrospective cohort study. SettingFive ICUs with their totally 130 beds in Taiwan. Patients or participantsARDS patients under invasive ventilation. InterventionsNo. Main variables of interest28-D mortality. ResultTotally 382 patients, with 6958 ventilator settings eligible for lung protection, were classified into low (mean VT=6.7ml/kg), intermediate (mean VT=8.9ml/kg) and high (mean VT=11.2ml/kg) VT groups. With similar baseline ARDS and ICU severities, intermediate and low VT groups did not differ in 28-D mortality (47% vs. 63%, P=0.06) or other outcomes such as 90-D mortality, ventilator-free days, ventilator-dependence rate. Multivariate analysis revealed high VT was independently associated with 28-D and 90-D mortality, but intermediate VT was not significantly associated with 28-D mortality (HR 1.34, CI 0.92–1.97, P=0.13) or 90-D mortality. When the intermediate and low VT groups were matched in propensity scores (n=66 for each group), their outcomes were also not significantly different. ConclusionIntermediate VT, with its outcomes similar to small VT, is an acceptable option for ventilated ARDS patients. This conclusion needs verification through clinical trials.

Morphology of Peri-Implant Tissues Around Permanent Prostheses With Various Emergence Angles Following Free Gingival Grafting.

To analyze the tissue morphology around implant-supported prostheses by digital technology and to evaluate the effect of prosthetic contours on the changes in tissues following the free gingiva graft procedure. A total of 53 implants in 32 patients receiving free gingiva grafts were selected. These had previously presented insufficient keratinized mucosa width (KMW). At the follow-up visits (mean: 16.66 ± 9.97 months), the implant position and tissue condition were documented with an oral scanner. Vertical soft tissue thickness (VT), measured from the implant-abutment connection to the marginal tissues, and horizontal soft tissue thickness (HT), at the level of the platform, were calculated. The VT, HT, and emergence angle (EA) of prostheses were assessed by 3Shape analyzing software. The final KMW was measured by clinical assessment. Marginal bone loss (MBL) was calculated in the follow-up bitewing radiographs. The mean VT in the study was 2.65 ± 0.75 mm at the mid-buccal sites, 3.74 ± 1.22 mm at the mesial, 3.16 ± 1.08 mm at the distal, and 2.53 ± 0.92 at the mid-lingual aspects. The mid-buccal HT was 1.45 ± 0.53 mm while the mid-lingual was 1.05 ± 0.43 mm (p = 0.008). Interestingly, prostheses with mid-buccal EA 30° exhibited slightly lower VT, but higher HT, than the ones with EA 30°. Prostheses with proximal EA > 30° displayed slightly more MBL, compared to prostheses with EA 30°. The mean KMW was 4.08 ± 1.10 mm. Free gingival grafting is a predictable treatment approach to augmenting soft tissue 3-dimensionally. Prostheses with EA 30° were preferable for preserving the maximal VT and maintaining crestal bone stability.

A pilot evaluation of respiratory mechanics during prehospital manual ventilation

IntroductionRespiratory mechanics, such as tidal volume (VT) and inspiratory pressures, may affect outcome in hospitalized patients with respiratory failure. Little is known about respiratory mechanics in the prehospital setting. MethodsIn this prospective, pilot investigation of patients receiving prehospital advanced airway placement, paramedics applied a device to measure respiratory mechanics. We evaluated tidal volume (VT) per predicted body weight (VTPBW) to determine the proportion of breaths within the lung-protective range of 4–10 mL/kg per PBW overall, according to ventilation bag volume (large versus small) and cardiac arrest status (active CPR, post-ROSC, non-arrest). ResultsOver 16-months, 7371 post-intubation breaths were measured in 54 patients, 32 patients with cardiac arrest and 22 with other conditions. Paramedics ventilated 19 patients with a small bag and 35 patients with a large bag. Overall, mean VT was 435 mL (95% CI 403, 467); VTPBW was 7.0 mL/kg (95% CI 6.4, 7.6) with 75% within the lung-protective range. Mean VTPBW and peak pressure differed according to arrest status (absolute difference −0.36 mL/kg and 32 cmH2O for active CPR compared to post-ROSC), though not according to bag size. ConclusionsWe observed that measuring respiratory mechanics in the prehospital setting was feasible. Tidal volumes were generally delivered within a safe range. Respiratory mechanics varied most significantly with active CPR with lower VTPBW and higher peak pressures, though did not seem to be affected by bag size. Future work might examine the relationship between respiratory mechanics and outcomes, which may identify opportunities to improve clinical outcomes.

Integration of structural and functional data in VT ablation -- SENSE2 protocol mapping

Abstract Funding Acknowledgements Type of funding sources: None. Background We have previously developed the sense protocol functional substrate mapping technique for VT ablation(1). However, functional substrate characterizaiton can involve protracted mapping time. Purpose We incorporated the integration of MRI data using ADAS-3D software into the mapping workflow, to integrate structural mapping information into the functional mapping substrate characterization, in order to improve procedural efficiency. Methods CMRs were performed in 20 patients with ischemic related VT and VT therapy in the previous 6 months. These were processed with the ADAS-3D software to characterize the extent of ventricular scars and also ADAS corridors which may correlate with VT channels. Focused substrate maps were then performed in patients, guided by the extent of ADAS scar and corridors, looking at the scar substrate in intrinsic rhythm and then functional channels using single extra pacing from the RV at 20ms above ERP (SENSE2 Protocol). Specifically healthy areas 2cm beyond the scar borderzone based on ADAS were not mapped, in order to reduce substrate mapping time and complete geometries were not created. Following delineation of functional channels pacemapping and entrainment mapping were used to confirm targets for ablation. The ADAS 3D MRI was integrated into the into the VT substrate map on Ensite-Precision with alignment to the aorta, RV and PA (Figure 1). We compared our data with previous functional mapping data without the integration of MRI. Results 20 patients (age 70 years; 19 male subjects) underwent ablation. Mean EF 28%. Median procedure time was 161 minutes compared with 246 minutes (in our previous study)(p=&amp;lt;0.001) Mean substrate mapping time was 32 mins vs 63 mins (p=&amp;lt;0.001). Mean ablation time was 22 mins vs 32 mins (p=0.11). 85% (17 of 20) patients were free from symptomatic VT/ anti-tachycardia pacing or implantable cardioverter defibrillator shocks at a median follow-up of 171 days. The mean VT burden was reduced from 22 events per patient in the 6 months’ pre-ablation to 1 event per patient in the median follow up period of 171 days post ablation (p=0.02). Mean shocks per-patient burden decreased from 3.5 to 0.08 in the same time period(p=0.03). Conclusion The SENSE2 protocol involves the integration of structural and functional data into the VT workflow for substrate characterization. It enables focused substrate maps to be performed without the need for complete geometry to be created in large ventricles. Outcomes compare favourably with our previous data but with significantly shorter procedure times. This streamlined workflow has the potential to improve care in VT ablation by shortening procedure times with similar outcomes which may reduce risks for the patient. Figure 1: Comparison of Voltage Map with MRI scar &amp; corridors using ADAS

Intermediate tidal volume is an acceptable option for ventilated patients with acute respiratory distress syndrome.

ObjectiveEvidence only proves low surpasses high tidal volume (VT) for acute respiratory distress syndrome (ARDS). Intermediate VT is a common setting for ARDS patients and has been demonstrated as effective as low VT in non-ARDS patients. The effectiveness of intermediate VT in ARDS has not been studied and is the objective of this study.DesignA retrospective cohort study.SettingFive ICUs with their totally 130 beds in Taiwan.Patients or participantsARDS patients under invasive ventilation.InterventionsNo.Main variables of interest28-D mortality.ResultTotally 382 patients, with 6958 ventilator settings eligible for lung protection, were classified into low (mean VT = 6.7 ml/kg), intermediate (mean VT = 8.9 ml/kg) and high (mean VT = 11.2 ml/kg) VT groups. With similar baseline ARDS and ICU severities, intermediate and low VT groups did not differ in 28-D mortality (47% vs. 63%, P = 0.06) or other outcomes such as 90-D mortality, ventilator-free days, ventilator-dependence rate. Multivariate analysis revealed high VT was independently associated with 28-D and 90-D mortality, but intermediate VT was not significantly associated with 28-D mortality (HR 1.34, CI 0.92–1.97, P = 0.13) or 90-D mortality. When the intermediate and low VT groups were matched in propensity scores (n = 66 for each group), their outcomes were also not significantly different.ConclusionIntermediate VT, with its outcomes similar to small VT, is an acceptable option for ventilated ARDS patients. This conclusion needs verification through clinical trials.

Comparison between Pediatric-Sized and Adult-Sized Bag-Valve-Mask Ventilation for Achieving Appropriate Tidal Volume in Simulated Adult Out-of-Hospital Cardiac Arrest in a Moving Ambulance

Background: Previous studies proposed that ventilation with pediatric-sized bag-valve-mask (BVM) ventilation resulted in more appropriate tidal volume (Vt) in adult patients than adult-sized BVM ventilation. However, those studies were conducted in stationary, non-moving environment. The authors hypothesized that the result of BVM ventilation in this treatment setting may be different when the investigation was conducted in a moving ambulance. Objective: To compare pediatric-sized and adult-sized BVM ventilation for achieving appropriate Vt in simulated adult out-of-hospital cardiac arrest (OHCA) in a moving ambulance. Materials and Methods: The present study was a randomized crossover trial. Registered nurses (RNs) and basic emergency medical technicians (EMT-Bs) were recruited to perform resuscitation ventilation on a medical training manikin. All participants performed both the pediatric-sized at 500 cc, and the adult-sized at 1,600 cc, BVM ventilation during 30 to 2 chest compressions to ventilation ratio during simulated OHCA in a moving ambulance. Adult-sized mask was used for both scenarios. The manikin was ventilated for 10 minutes during each scenario. The percentage of appropriate Vt was compared between scenarios. The percentages of low Vt at less than 400 cc and high Vt at more than 600 cc between groups were also evaluated. Results: Fifty-two volunteers with 57.7% RNs and 42.3% EMT-Bs were included. Of those 52 volunteers, 44 had less than five years of pre-hospital ventilation experience. The mean Vt was 239.0 cc and 444.5 cc in the pediatric-sized and the adult-sized BVM groups, respectively (p&lt;0.001). Low Vt was observed in 100% of pediatric-sized BVM ventilation. In the adult-sized ventilation group, 52.1±25.6% had appropriate Vt, 11.4±18.6% had high Vt, and 36.5±29.1% had low Vt (p&lt;0.001). Conclusion: A comparison between pediatric-sized and adult-sized BVM ventilation in simulated adult OHCA in a moving ambulance demonstrated the superiority of the adult-sized BVM over the pediatric-sized BVM for achieving appropriate Vt in adult OHCA. Keywords: Bag-valve-mask ventilation; Tidal volume; Out-of-hospital cardiac arrest; Ambulance

Effect of human milk and other neonatal variables on lung function at three months corrected age

To evaluate the impact of human milk and different neonatal variables on tidal breathing flow-volume loop (TBFVL) parameters within three months' corrected age (CA) in infants born ≤32 wks or weighing <1500 g. We retrospectively studied 121 infants with gestational age (GA) ≤ 32 weeks or birth weight (BW) <1500 gr who had lung function assessment within three months' CA by TBFVL analysis between June 2009 and April 2018. We investigated the impact of GA, gender, being Small for GA (SGA), sepsis, days of mechanical ventilation (MV) and human milk feeding (HMF) on later respiratory function, both in the entire group and according to BW ( ≤1000 g and >1000 g). The mean(SD) z-score for tidal volume (Vt) and time to peak expiratory flow to expiratory time (tPTEF/tE) were respectively -4.3 (2.5) and -0.8 (2.0) for the overall population with no significant differences between infants <1000 g or ≥1000 g. The mean(SD) Vt standardized for body weight was 6.2(2.0) ml/kg. Being female was associated with better Vt/Kg, whereas longer MV or being born SGA were associated with worst tPTEF/tE. For infants with BW < 1000 gr, tPTEF/tE was positively associated with HMF. An early TBFVL assessment within three months' CA already reveals lung function alteration in preterm infants. Being female is associated with better Vt/Kg, while longer duration of MV or being born SGA negatively affect tPTEF/tE. The positive association between HMF and better tPTEF/tE in infants with BW <1000 g has emerged, which deserves further investigation.

Reduced microglia activity in patients with long-term immunosuppressive therapy after liver transplantation

PurposeCalcineurin inhibitors (CNI) can cause long-term impairment of brain function. Possible pathomechanisms include alterations of the cerebral immune system. This study used positron emission tomography (PET) imaging with the translocator protein (TSPO) ligand 18F-GE-180 to evaluate microglial activation in liver-transplanted patients under different regimens of immunosuppression.MethodsPET was performed in 22 liver-transplanted patients (3 CNI free, 9 with low-dose CNI, 10 with standard-dose CNI immunosuppression) and 9 healthy controls. The total distribution volume (VT) estimated in 12 volumes-of-interest was analyzed regarding TSPO genotype, CNI therapy, and cognitive performance.ResultsIn controls, VT was about 80% higher in high affinity binders (n = 5) compared to mixed affinity binders (n = 3). Mean VT corrected for TSPO genotype was significantly lower in patients compared to controls, especially in patients in whom CNI dose had been reduced because of nephrotoxic side effect.ConclusionOur results provide evidence of chronic suppression of microglial activity in liver-transplanted patients under CNI therapy especially in patients with high sensitivity to CNI toxicity.

A first-in-human study of 11C-MTP38, a novel PET ligand for phosphodiesterase 7

PurposePhosphodiesterase 7 (PDE7) is an enzyme that selectively hydrolyses cyclic adenosine monophosphate, and its dysfunction is implicated in neuropsychiatric diseases. However, in vivo visualization of PDE7 in human brains has hitherto not been possible. Using the novel PET ligand 11C-MTP38, which we recently developed, we aimed to image and quantify PDE7 in living human brains.MethodsSeven healthy males underwent a 90-min PET scan after injection of 11C-MTP38. We performed arterial blood sampling and metabolite analysis of plasma in six subjects to obtain a metabolite-corrected input function. Regional total distribution volumes (VTs) were estimated using compartment models, and Logan plot and Ichise multilinear analysis (MA1). We further quantified the specific radioligand binding using the original multilinear reference tissue model (MRTMO) and standardized uptake value ratio (SUVR) method with the cerebellar cortex as reference.ResultsPET images with 11C-MTP38 showed relatively high retentions in several brain regions, including in the striatum, globus pallidus, and thalamus, as well as fast washout from the cerebellar cortex, in agreement with the known distribution of PDE7. VT values were robustly estimated by two-tissue compartment model analysis (mean VT = 4.2 for the pallidum), Logan plot, and MA1, all in excellent agreement with each other, suggesting the reversibility of 11C-MTP38 binding. Furthermore, there were good agreements between binding values estimated by indirect method and those estimated by both MRTMO and SUVR, indicating that these methods could be useful for reliable quantification of PDE7. Because MRTMO and SUVR do not require arterial blood sampling, they are the most practical for the clinical use of 11C-MTP38-PET.ConclusionWe have provided the first demonstration of PET visualization of PDE7 in human brains. 11C-MTP38 is a promising novel PET ligand for the quantitative investigation of central PDE7.

Efficacy of epicardial and endocardial ablation in the prevention of ventricular tachycardia in arrythmogenic right ventricular cardiomyopathy- a meta analysis

Abstract Introduction Ventricular tachycardia is a major complication associated with increased risk of sudden cardiac death in arrhythmogenic ventricular cardiomyopathy. Recurrence of VT status post catheter endocardial ablation with conventional mapping is a evolving discussion in management of VT prevention in ARVC. With the evolution of new mapping techniques to locate ectopic foci of VT, a combination of endo- and epicardial catheter ablation have proven to be efficacious in the prevention of frequency of VT recurrence and its duration. Methods Using PubMed, Ovid (MEDLINE) and Cochrane database we searched using the MeSH terms including: “arrhythmogenic right ventricular cardiomyopathy”, “arrhythmogenic right ventricular dysplasia”, “monomorphic ventricular tachycardia”, “polymorphic ventricular Tachycardia”, “endocardial catheter ablation”, “epicardial catheter ablation”. The primary outcomes were to assess VT frequency and duration status post endocardial or epicardial or a combination of both types of ablation. The secondary outcome includes sudden cardiac arrest or sudden cardiac death after procedure. ANOVA with post HOC analysis was performed using SPSS v.26 (IBM Corp, NY, USA) Results A total of 33 studies included 1437 patients with a mean male=67%. The data analysis showed a mean VT prevention for endocardial ablation was 65%, epicardial 78%, and for combined epi-endocardial was 89% (figure-1). The mean procedural mortality rate was 2%. In order to test the hypothesis that combined epi-endocardial ablation was more successful in the prevention of VT recurrence, we performed a one-way analysis of variance (ANOVA). The analysis was statistically significant F(2,14)=5.879, 95% CI, p=0.014. Post Hoc test (Tukey HSD test) with multiple comparisons indicated that patients who underwent combined epi-endocardial ablation experienced a statistically significant difference in VT prevention of 89% (95% CI p=0.01) compared to only endocardial ablation, mean VT prevention of 65% (95% CI, p=0.189) or only epicardial, mean VT prevention of 78% (95% CI, p=0.353). Conclusion With new mapping techniques, use of endocardial, and epicardial ablation is linked to decrease VT frequency, duration, ICD shocks, and sudden cardiac death in patients with ARVC in cohorts with prior failure of antiarrhythmics. Total VT Prevention across target sites Funding Acknowledgement Type of funding source: None

Changes in the Rate of Postoperative Flexor Tendon Rupture in Patients with Distal Radius Fractures.

Background: Flexor tendon rupture is a major complication after volar locking plating for distal radius fracture (DRF). Few studies have investigated changes in the rate of postoperative flexor tendon rupture in patients with DRFs. The present study aimed to investigate the changes in the rate of postoperative flexor tendon rupture and to assess plate placement and reduction positions. Methods: We retrospectively reviewed patients in whom more than 24 months had passed since DRF surgery. The patients were interviewed by telephone. Forty-nine patients (50 fractures; 2007-2009) from institution A were included in group 1 and 81 patients (84 fractures; 2013-2016) from institution B were included in group 2. The DRF surgery method was similar between the two groups. The rate of flexor tendon rupture, Soong classification grade, and radiological index (i.e., volar tilt [VT], radial inclination [RI], and ulnar variance [UV]) were statistically investigated in both groups. Results: Patient epidemiology was not significantly different between the two groups. The flexor tendon rupture rates were 2% and 0% in groups 1 and 2, respectively, without a significant difference. With regard to the Soong grade, 44 fractures were grade 2 and 6 were grade 1 in group 1, whereas 18 were grade 2, 38 were grade 1, and 28 were grade 0 in group 2, with a significant difference (p < 0.05). With regard to the radiological index, the mean VT values were 5° and 11° in groups 1 and 2, respectively, with a significant difference (p < 0.05). However, RI and UV showed no significant difference. Conclusions: Plate placement and reduction positions, which are risk factors for flexor tendon ruptures after DRFs, have improved recently when compared with previous findings. With these changes, the rate of flexor tendon rupture is presumed to have decreased.

Characterization of chemotherapy-induced peripheral neuropathy (CIPN) using patient-reported outcomes (PRO) and quantitative sensory testing (QST).

e24078 Background: CIPN is a common, potentially debilitating, and dose-limiting side effect experienced by cancer survivors. CIPN encompasses symptoms such as pain, numbness, and tingling, which can be measured subjectively by PRO, or semi-objectively by QST; however, little is known about how QST measures differ among patients with and without CIPN, or if QST outcomes correlate with symptom profiles measured by PRO. Methods: CIPN is a common, potentially debilitating, and dose-limiting side effect experienced by cancer survivors. CIPN encompasses symptoms such as pain, numbness, and tingling, which can be measured subjectively by PRO, or semi-objectively by QST; however, little is known about how QST measures differ among patients with and without CIPN, or if QST outcomes correlate with symptom profiles measured by PRO. Results: 116 patients with CIPN and 10 control patients without CIPN were analyzed. NRS and FACT/GOG-Ntx scores were significantly worse in the CIPN group compared to controls (all p&lt; 0.001). The mean (Standard Deviation) TT for CIPN and control patients was 3.61 (0.43) and 3.38 (0.32), respectively (p = 0.059), in hands; and 3.86 (0.70) and 3.38 (0.56), respectively (p = 0.043), in feet. The mean VT was 6.06 (3.45) and 3.87 (1.01), respectively (p=0.032), in hands; and 19.14 (11.09) and 8.43 (3.22), respectively (p&lt;0.001), in feet. There was no significant difference in THT between groups. The correlation coefficients between PRO with QST measures in all patients are listed in the table below. Conclusions: Our study suggested that patients with CIPN have significantly worse symptoms and tactile and vibratory threshold measured by QST when compared with controls. Mild to moderate correlations were observed between PROs and QST, suggesting that CIPN symptoms severity correspond to sensory sensitivity. As CIPN presents a diverse range of symptoms, improved quantification of subjective and objective measures for CIPN can help the incorporation of these tools into future clinical trials. Clinical trial information: NCT03183037 and NCT03292328 . [Table: see text]

Body Mass Index and Age Effects on Brain 11β-Hydroxysteroid Dehydrogenase Type 1: a Positron Emission Tomography Study.

Cortisol, a glucocorticoid steroid stress hormone, is primarily responsible for stimulating gluconeogenesis in the liver and promoting adipocyte differentiation and maturation. Prolonged excess cortisol leads to visceral adiposity, insulin resistance, hyperglycemia, memory dysfunction, cognitive impairment, and more severe Alzheimer's disease phenotypes. The intracellular enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of inactive cortisone to active cortisol; yet the amount of 11β-HSD1 in the brain has not been quantified directly in vivo. We analyzed positron emission tomography (PET) scans with an 11β-HSD1 inhibitor radioligand in twenty-eight individuals (23M/5F): 10 lean, 13 overweight, and 5 obese individuals. Each individual underwent PET imaging on the high-resolution research tomograph PET scanner after injection of 11C-AS2471907 (n= 17) or 18F-AS2471907 (n= 11). Injected activity and mass doses were 246 ± 130MBq and 0.036 ± 0.039μg, respectively, for 11C-AS2471907, and 92 ± 15MBq and 0.001 ± 0.001μg for 18F-AS2471907. Correlations of mean whole brain and regional distribution volume (VT) with body mass index (BMI) and age were performed with a linear regression model. Significant correlations of whole brain mean VT with BMI and age (VT = 15.23-0.63 × BMI + 0.27 × Age, p = 0.001) were revealed. Age-adjusted mean whole brain VT values were significantly lower in obese individuals. Post hoc region specific analyses revealed significantly reduced mean VT values in the thalamus (lean vs. overweight and lean vs. obese individuals). Caudate, hypothalamus, parietal lobe, and putamen also showed lower VT value in obese vs. lean individuals. A significant age-associated increase of 2.7mL/cm3 per decade was seen in BMI-corrected mean whole brain VT values. In vivo PET imaging demonstrated, for the first time, correlation of higher BMI (obesity) with lower levels of the enzyme 11β-HSD1 in the brain and correlation of increased 11β-HSD1 levels in the brain with advancing age.

Comparing positive pressure ventilation efficacy of a novel foot operated resuscitator with self-inflating bag and mask in a manikin model

AimTo compare positive pressure ventilation efficacy of a novel foot operated resuscitator (FOR) during positive pressure ventilation with that of self-inflating bag and mask (SIBM) using a manikin model.MethodA comparative...

Evaluation of the total distribution volume of 18F-FBPA in normal tissues of healthy volunteers by non-compartmental kinetic modeling

ObjectiveBoron neutron capture therapy (BNCT) is a noninvasive radiation therapy method for cancer treatment. In BNCT, 4-borono-2-[18F]-fluoro-L-phenylalanine (18F-FBPA) PET has been employed to estimate 10B accumulation in target tumors and normal tissues if 10B borono-L-phenylalanine (10B-BPA) is used as a boron carrier. The purpose of the current study was to evaluate the total distribution volume (Vt) of 18F-FBPA in normal organs of healthy volunteers by kinetic analysis and to estimate boron concentration in normal organs for the therapeutic dose of 10B-BPA using obtained Vt values.MethodsSix healthy volunteers were injected with 18F-FBPA (3–5 MBq/kg), and 7 PET-CT scans were performed subsequently. 18F-FBPA radioactivity in whole blood and plasma was measured before, and eight times after the injection. PET images were analyzed by PMOD software. Twelve volumetric regions of interest including the brain, heart, right lung, spleen, liver, parotid salivary glands, esophagus, stomach, pancreas, intestines, and bone marrow were drawn manually for each subject and analyzed with the Logan plot and two Ichise multilinear analyses (MA1 and MA2). The better model was defined by several goodness-of-fit parameters and residual distribution. After Vt values had been derived, boron concentration was estimated in ppm for the 10B-BPA-fructose (10B-BPA-fr) dose 30 g 1 and 2 h post-injection using Vt and interpolated plasma activity data.ResultsThe Ichise MA2 model showed the best fit among all models. Akaike Information Criterion (AIC) was the lowest for the Ichise’s MA2 in all regions (mean AIC value − 14.0) comparing to the other models (Logan plot mean AIC 31.4; Ichise MA1 model mean AIC − 4.2). Mean Vt values of the Ichise MA2 model ranged from 0.94 ± 0.14 ml/ml in the pancreas to 0.16 ± 0.02 ml/ml in the right lung. Estimated boron concentration for 10B-BPA-fr had the highest value in the pancreas (14.0 ± 1.9 ppm 1 h after, and 5.7 ± 1.7 ppm 2 h after the 18F-FBPA administration) and the lowest value in the right lung (2.4 ± 0.3 ppm 1 h, and 1.0 ± 0.3 ppm 2 h post-injection).ConclusionThe 10B concentration in normal tissues was best estimated using Vt values of 18F-FBPA with the Ichise multilinear analysis 2 (MA2).Trail registryThe UMIN clinical trial number: UMIN000022850.