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Objectives Quantitative sensory testing may help predict treatment responses in individuals with chronic pain. Our objective was to determine whether evoked pain sensitivity at baseline predicted preferential treatment responses to either emotional awareness and expression therapy (EAET) or cognitive behavioral therapy (CBT) in individuals with fibromyalgia (FM). Methods This was a secondary analysis of a previous randomized clinical trial, in which individuals with FM were randomized to EAET, CBT, or Education as a control intervention. Only females who completed baseline and post-treatment assessments were analyzed (n=196). The primary outcome was change in overall clinical pain severity from pretreatment to posttreatment, and the primary predictor of interest was pressure pain tolerance at baseline. Results Among patients with low pain tolerance at baseline (n=154), both EAET and CBT led to small but significant improvements in clinical pain severity (CBT mean=0.66, 95% confidence interval [0.24-1.07]; EAET mean=0.76 [0.34-1.17]). Conversely, in patients with normal pain tolerance (n=42), there was no significant improvement in clinical pain after CBT (0.13 [-0.88 to 1.14]), a small improvement after FM Education (0.81 [0.14-1.48]), but a much larger and statistically significant improvement after EAET (2.14 [1.23-3.04]). Discussion Normal levels of pressure pain tolerance at baseline predicted greater improvement in clinical pain severity after EAET than CBT. Quantitative sensory testing may provide insights about individual responses to psychologically based therapies for individuals with chronic pain.

INTRODUCTION AND OBJECTIVE:It has been hypothesized that some overactive bladder (OAB) patients may have central sensitization and/or increased sensitivity to sensory stimuli (“sensory/afferent hyp...

Experimental pain sensitivity was assessed in individuals with urologic chronic pelvic pain syndrome (UCPPS) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. A series of computer-controlled pressure stimuli were delivered to the thumbnail bed, an asymptomatic site distant from the area of UCPPS pain that is considered to be indicative of overall body pain threshold. Stimuli were rated according to a standardized magnitude estimation protocol. Pain sensitivity in participants with UCPPS was compared with healthy controls and a mixed pain group composed of individuals with other chronic overlapping pain conditions, including fibromyalgia, chronic fatigue, and irritable bowel syndromes. Data from 6 participating MAPP testing sites were pooled for analysis. Participants with UCPPS (n = 153) exhibited an intermediate pain sensitivity phenotype: they were less sensitive relative to the mixed pain group (n = 35) but significantly more sensitive than healthy controls (n = 100). Increased pain sensitivity in patients with UCPPS was associated with both higher levels of clinical pain severity and more painful body areas outside the pelvic region. Exploratory analyses in participants with UCPPS revealed that pain sensitivity increased during periods of urologic symptom flare and that less pressure pain sensitivity at baseline was associated with a greater likelihood of subsequent genitourinary pain improvement 1 year later. The finding that individuals with UCPPS demonstrate nonpelvic pain hypersensitivity that is related to clinical symptoms suggests that central nervous system mechanisms of pain amplification contribute to UCPPS.

Dentists regularly employ a variety of self‐report and sensory techniques to aid in the diagnosis and treatment of tooth‐related disease. Many of these techniques leverage principles borrowed from psychophysics, the quantitative measurement of the relationship between stimuli and evoked sensations, which falls under the larger umbrella of quantitative sensory testing (QST). However, most clinicians fail to meet the bar for what could be considered quantitative sensory testing, and instead focus on qualitative and dichotomous “yes/no” aspects of sensory experience. With our current subjective measurements for pain assessments, diagnosis and treatment of dental pain in young children and individuals (any age) with severe cognitive impairment rely extensively on third‐party observations. Consequently, the limitation of inadequate pain diagnosis can lead to poor pain management. In this review, it discusses mechanisms that underlie acute and chronic dental pain. It details the measurement of somatosensory responses and pulpal blood flow as objective measures of tooth health and pain. It proposes that bridging these varied methodologies will significantly improve diagnosis and treatment of orofacial pain and pathology. It concludes that improving the precision of sensory measurements could yield important improvements in diagnostic challenges in pulpal pathology for noncommunicative and cognitively impaired individuals.

The American Society of Anesthesiologists Standards for Basic Monitoring recommends blood pressure (BP) measurement every 5 min. Research has shown distractions or technical factors can cause prolonged measurement intervals exceeding 5 min. We investigated the relationship between prolonged non-invasive BP (NIBP) measurement interval and the incidence of hypotension, detected postinterval. Our secondary outcome was to determine independent predictors of these prolonged NIBP measurement intervals. Retrospective data were analyzed from 139,509 general anesthesia cases from our institution’s Anesthesia Information Management System (AIMS). Absolute hypotension (AH) was defined a priori as a systolic BP < 80 mmHg and relative hypotension (RH) was defined as a 40% decrease in systolic BP from the preoperative baseline. Odds ratios (OR) with 95% confidence intervals and Pearson’s Chi square Test reported the association of prolonged NIBP measurement intervals on hypotension detected post-NIBP measurement interval. Logistic regression models were developed to determine independent predictors of NIBP measurement intervals. The analysis revealed that NIBP measurement intervals greater than 6 and 10 min are associated with an approximately four times higher incidence of a patient transitioning into hypotension (AH/RH > 6 min OR 4.0 / 3.6; AH/RH > 10 min OR 4.3 / 3.9; p< 0.001). A key finding was that the “> 10-minute AH model” indicated that age 41–80, increased co-morbidity profile, obesity and turning (repositioning) of the operative room table were significant predictors of prolonged NIBP measurement intervals (p < 0.001). While we do not suggest NIBP measurement intervals cause hypotension, intervals greater than 6 and 10 min are associated with a fourfold increase in the propensity of an undetected transition into both RH or AH. These data support current monitoring guidelines.

To review the scientific literature pertaining to the use of hand-carried and hand-held ultrasound devices in low- and middle-income countries (LMIC), with a focus on clinical applications, geographical areas of use, the impact on patient management and technical features of the devices used.; The electronic databases PubMed and Google Scholar were searched. No language or date restrictions were applied. Case reports and original research describing the use of hand-carried ultrasound devices in LMIC were included if agreed upon as relevant by two-reviewer consensus based on our predefined research questions.; A total of 644 articles were found and screened, and 36 manuscripts were included for final review. Twenty-seven studies were original research articles, and nine were case reports. Several reports describe the successful diagnosis and management of difficult, often life-threatening conditions, using hand-carried and hand-held ultrasound. These portable ultrasound devices have also been studied for cardiac screening exams, as well as a rapid triage tool in rural areas and after natural disaster. Most applications focus on obstetrical and abdominal complaints. Portable ultrasound may have an impact on clinical management in up to 70% of all cases. However, no randomised controlled trials have evaluated the impact of ultrasound-guided diagnosis and treatment in resource-constrained settings. The exclusion of articles published in journals not listed in the large databases may have biased our results. Our findings are limited by the lack of higher quality evidence (e.g. controlled trials).; Hand-carried and hand-held ultrasound is successfully being used to triage, diagnose and treat patients with a variety of complaints in LMIC. However, the quality of the current evidence is low. There is an urgent need to perform larger clinical trials assessing the impact of hand-carried ultrasound in LMIC.

Analgesic trials frequently fail to demonstrate efficacy of drugs known to be efficacious. Poor pain reporting accuracy is a possible source for this low essay-sensitivity. We report the effects of Accurate-Pain-Reporting-Training (APRT) on the placebo response in a trial of Pregabalin for painful-diabetic-neuropathy. The study was a two-stage randomized, double-blind trial: In Stage-1 (Training) subjects were randomized to APRT or No-Training. The APRT participants received feedback on the accuracy of their pain reports in response to mechanical stimuli, measured by R-square score. In Stage-2 (Evaluation) all subjects entered a placebo-controlled, cross-over trial. Primary (24-h average pain intensity) and secondary (current, 24-h worst, and 24-h walking pain intensity) outcome measures were reported. Fifty-one participants completed the study. APRT patients (n = 28) demonstrated significant (p = 0.036) increases in R-square scores. The APRT group demonstrated significantly (p = 0.018) lower placebo response (0.29 ± 1.21 vs. 1.48 ± 2.21, mean difference ± SD = -1.19±1.73). No relationships were found between the R-square scores and changes in pain intensity in the treatment arm. In summary, our training successfully increased pain reporting accuracy and resulted in a diminished placebo response. Theoretical and practical implications are discussed.

This study measures the vascular wall shear rate at the vessel edge using decorrelation based ultrasound speckle tracking. Results for nine healthy and eight renal disease subjects are presented. Additionally, the vascular wall shear rate and circumferential strain during physiologic pressure, pressure equalization and hyperemia are compared for five healthy and three renal disease subjects. The mean and maximum wall shear rates were measured during the cardiac cycle at the top and bottom wall edges. The healthy subjects had significantly higher mean and maximum vascular wall shear rate than the renal disease subjects. The key findings of this research were that the mean vascular wall shear rates and circumferential strain changes between physiologic pressure and hyperemia that was significantly different between healthy and renal disease subjects.

Intelligent agents have been earmarked as the key enabling technology to provide the flexibility required by modern, competitive, customer-orientated manufacturing environments. Rational agent behavior is of paramount importance when interacting with these environments to ensure significant losses are not incurred. To achieve rationality, intelligent agents must constantly balance technical (process) and economic (enterprise wide) trade-offs through co-operation, learning and autonomy. The research presented in this manuscript integrates methodological commonalities in intelligent manufacturing research and prognostics to design and evaluate a generic architecture for the core services of self-learning, rational, machining process regulation agents. The proposed architecture incorporates learning, flexibility and rational decision making through the integration of heterogeneous intelligent algorithms (i.e. neural networks and genetic algorithms) from fields such as machine learning, data mining and statistics. The architecture's ability to perceive, learn and optimize is evaluated on a high-volume industrial gun drilling process.

Introduction: Home telemetry monitoring with accurate automated rhythm classification can have important clinical benefits in the timely diagnosis and appropriate management of patients with atrial fibrillation (AF). We clinically validated a novel personal e-Health device and algorithm developed to distinguish AF from sinus rhythm (SR). Methods: A handheld electrocardiogram (ECG) recording system (Maestro) and signal processing platform were developed. The Maestro provides an LCD interface that continuously shows an ECG, heart rate, and heart rhythm status. Twenty second ECG signals analogous to Lead I were acquired from 66 patients presenting to the arrhythmia clinic at the University of Michigan Hospital either in SR or AF. Electrograms were segmented into non-overlapping 6-second samples and one random segment per patient was selected for analysis by the Maestro system. Simultaneous 5 or 12 lead ECGs were obtained from these patients and 3 expert physicians blinded to the Maestro analysis identified the rhythm as SR or AF. The Maestro system applied several signal conditioning algorithms to each ECG sample. The dimensionless temporal R-R interval variability (VRR) index and spectral frequency dispersion metric (FDM) were computed. Results: The 2-dimensional scatter-gram of the samples demonstrated 2 distinct clusters of VRR and FDM for patients with SR and AF. The VRR index clusters for SR and AF patients were 0.018 ± 0.013 and 0.187 ± 0.073 (mean±std), respectively (p < 0.001). The FDM clusters for SR and AF patients occurred at 10.5 ± 5.916 and 15.892 ± 3.337, respectively (p < 0.001). We developed a Gaussian Mixed Model (GMM) classifier to distinguish between the AF and SR clusters. Only after the GMM classifier was obtained were the Maestro classifications compared to the physicians’ readings. The algorithm correctly categorized AF (N = 46) and SR (N = 20) for all Maestro segments analyzed with 100% specificity and sensitivity. Conclusion: The Maestro handheld telemetry unit utilizes a novel classification algorithm and was demonstrated to acquire and automatically analyze 6-second electrograms for rapid and accurate classification of patients in SR or AF in this initial clinical validation trial.

Management of fluid overload in patients with end-stage renal disease represents a unique challenge to clinical practice because of the lack of accurate and objective measurement methods. Currently, peripheral edema is subjectively assessed by palpation of the patient's extremities, ostensibly a qualitative indication of tissue viscoelastic properties. New robust quantitative estimates of tissue fluid content would allow clinicians to better guide treatment, minimizing reactive treatment decision making. Ultrasound viscoelastography (UVE) can be used to estimate strain in viscoelastic tissue, deriving material properties that can help guide treatment. We are developing and testing a simple, low-cost UVE system using a single-element imaging transducer that is simpler and less computationally demanding than array-based systems. This benchtop validation study tested the feasibility of using the UVE system by measuring the mechanical properties of a tissue-mimicking material under large strains. We generated depth-dependent creep curves and viscoelastic parameter maps of time constants and elastic moduli for the Kelvin model of viscoelasticity. During testing, the UVE system performed well, with mean UVE-measured strain matching standard mechanical testing with maximum absolute errors ≤4%. Motion tracking revealed high correlation and signal-to-noise ratios, indicating that the system is reliable.

Bioimpedance spectroscopy (BIS) has shown significant potential in many areas of medicine to provide new physiologic markers. Several acute and chronic diseases are accompanied by changes in intra- and extracellular fluid within various areas of the human body. The estimation of fluid in various body compartments is therefore a simple and convenient method to monitor certain disease states. In this work, the design and evaluation of a BIS instrument are presented and three key areas of the development process investigated facilitating the BIS measurement of tissue hydration state. First, the benefit of incorporating DC-stabilizing circuitry to the standard modified Howland current pump (MHCP) is investigated to minimize the effect of DC offsets limiting the dynamic range of the system. Second, the influence of the distance between the bioimpedance probe and a high impedance material is investigated using finite element analysis (FEA). Third, an analytic compensation technique is presented to minimize the influence of parasitic capacitance. Finally, the overall experimental setup is evaluated through ex vivo BIS measurements of porcine spleen tissue and compared to published results. The DC-stabilizing circuit demonstrated its ability to maintain DC offsets at less than 650 μV through 100 kHz while maintaining an output impedance of 1 MΩ from 100 Hz to 100 kHz. The proximity of a bioimpedance probe to a high impedance material such as acrylic was shown to increase measured impedance readings by a factor of 4x as the ratio of the distance between the sensing electrodes to the distance between the bioimpedance probe and acrylic reached 1:3. The average parasitic capacitance for the circuit presented was found to be 712 ± 128 pF, and the analytic compensation method was shown to be able to minimize this effect on the BIS measurements. Measurements of porcine spleen tissue showed close correlation with experimental results reported in published articles. This research presents the successful design and evaluation of a BIS instrument. Specifically, robust measurements were obtained by implementing a DC-stabilized current source, investigating probe-material proximity issues and compensating for parasitic capacitance. These strategies were shown to provide tissue measurements comparable with published literature.

We present an 8-bit sub-ranging SAR ADC designed for bursty signals having long time periods with small code spread. A modified capacitive-DAC (CDAC) saves previous sample’s MSB voltage and reuses it throughout subsequent conversions. This prevents unnecessary switching of large MSB capacitors as well as conversion cycles, reducing energy consumed in the comparator and digital logic and yielding total energy savings of 2.6×. In 0.18μm CMOS, the ADC consumes 120nW at 0.6V and 100kS/s with 46.9dB SNDR.

This study investigated the use of ultrasound speckle decorrelation- and correlation-based lateral speckle-tracking methods for transverse and longitudinal blood velocity profile measurement, respectively. By studying the blood velocity gradient at the vessel wall, vascular wall shear stress, which is important in vascular physiology as well as the pathophysiologic mechanisms of vascular diseases, can be obtained. Decorrelation-based blood velocity profile measurement transverse to the flow direction is a novel approach, which provides advantages for vascular wall shear stress measurement over longitudinal blood velocity measurement methods. Blood flow velocity profiles are obtained from measurements of frame-to-frame decorrelation. In this research, both decorrelation and lateral speckle-tracking flow estimation methods were compared with Poiseuille theory over physiologic flows ranging from 50 to 1000 mm/s. The decorrelation flow velocity measurement method demonstrated more accurate prediction of the flow velocity gradient at the wall edge than the correlation-based lateral speckle-tracking method. The novelty of this study is that speckle decorrelation-based flow velocity measurements determine the blood velocity across a vessel. In addition, speckle decorrelation-based flow velocity measurements have higher axial spatial resolution than Doppler ultrasound measurements to enable more accurate measurement of blood velocity near a vessel wall and determine the physiologically important wall shear.

Renal disease is epidemic in the United States with 8 × 106 people having chronic kidney disease (CKD) with a glomerular filtration rate of less than 60 ml/min and another 12 × 106 having evidence of microalbuminuria. Bleeding from biopsy is a major problem in many areas of medicine but particularly in nephrology where the risk of serious bleeding from the kidney, although infrequent, may become life threatening [1–4]. Risk factors associated with bleeding such as hypertension or other comorbidities have been studied [2,3]. However, while methods of performing kidney biopsies have improved over the last two decades, renal biopsies still entail inherent bleeding risk such that approximately a third may have postbiopsy hematoma [1,2]. Even though some modifiable risk factors are mitigated, most patients at increased risk are not biopsied. Even mild coagulopathies increase the risk such that conventional (percutaneous) renal biopsy is contraindicated [1,3,4]. While these and other published data indicate that serious bleeding complications occur in only 1%–2% of cases, the data are inherently biased by excluding the riskiest patients from percutaneous renal biopsy. Because of this bleeding risk, renal biopsy is used sparingly in the CKD population, ranging in western countries from 3.3 in 100,000 in Italy, to 21.5 in 100,000 in Australia [5]. While accurate biopsy rates in the US are lacking, using a median rate of 16.2 in 100,000 such as that reported for France [5], yields an estimate of approximately 50,000 renal biopsies annually in the US. The contraindication of biopsy is not optimal since the risk of bleeding is greater in many patient populations where renal biopsy would be most helpful, such as in autoimmune diseases and renal dysfunction manifested by elevated creatinine greater than 2 mg/dl [4]. Even though most hematoma do not become life threatening, the current strategy for monitoring and managing complications can be improved. Safer renal biopsy will allow more accurate diagnosis and better management of this epidemic health problem. Prior attempts at designing biopsy needles that deploy hemostatic agents have been made [6–9]. However, there are two shortcomings in prior designs. First, they attempt to deploy an unshielded hemostatic plug into the kidney (or other organ) tissue along the outside of the biopsy needle shaft during the biopsy procedure. These plugs will be met with resistance from the remaining organ tissue as it is introduced into the biopsy site, resulting in ineffective deployment. Second, no controlled deployment mechanism has been developed that will reliably fill the tissue void created by the biopsy needle with the hemostatic plug. Other designers have attempted to improve guidance and deployment mechanisms in standard two-stage biopsy needles [10–15], but these prior solutions do not address the problem of effective deployment of the hemostatic plug within the void as the needle is withdrawn. While there are a variety of approaches that may be taken to improve the current situation, we have chosen to develop a biopsy needle and mechanism that injects a hemostatic plug at the time of biopsy to control bleeding. This study evaluates the performance of a prototype biopsy device referred to as the therapeutic injection system (TIS). The TIS is designed to minimize the risk of bleeding complications by delivering a shielded hemostatic plug using a specialized delivery mechanism. The clotting and sealing caused by the plug material then completes the hemostatic action. The following two sections describe the design and validation of this device. Section 4 provides experimental results, followed by Secs. 5 and 6 presenting a discussion of the results and concluding remarks.

BACKGROUND: Anterior retraction of the tongue is used to enhance upper airway patency during pediatric fiberoptic intubation. This can be achieved by the use of Magill forceps as a tongue retractor, but lingual grip can become unsteady and traumatic. Our objective was to modify this instrument using computer-aided engineering for the purpose of stable tongue retraction. METHODS: We analyzed the geometry and mechanical properties of standard Magill forceps with a combination of analytical and empirical methods. This design was captured using computer-aided design techniques to obtain a 3-dimensional model allowing further geometric refinements and mathematical testing for rapid prototyping. RESULTS: On the basis of our experimental findings we adjusted the design constraints to optimize the device for tongue retraction. Stereolithography prototyping was used to create a partially functional plastic model to further assess the functional and ergonomic effectiveness of the design changes. To reduce pressure on the tongue by regular Magill forceps, we incorporated (1) a larger diameter tip for better lingual tissue pressure profile, (2) a ratchet to stabilize such pressure, and (3) a soft molded tip with roughened surface to improve grip. CONCLUSION: Computer-aided engineering can be used to redesign and prototype a popular instrument used in airway management. On a computational model, our modified Magill forceps demonstrated stable retraction forces, while maintaining the original geometry and versatility. Its application in humans and utility during pediatric fiberoptic intubation are yet to be studied.