The POCUS Pulse Check: A Case Series on a Novel Method for Determining the Presence of a Pulse Using Point-of-Care Ultrasound.

BACKGROUND: During cardiopulmonary resuscitation, pulse checks must be rapid and accurate. Despite the importance placed on the detection of a pulse, several studies have shown that health care providers have poor accuracy for detection of central pulses by palpation. To date, the use of point-of-care ultrasound (POCUS) in cardiac arrest has focused on the presence of cardiac standstill and diagnosing reversible causes of the arrest. OBJECTIVE: This case series highlights a simple, novel approach to determine whether pulses are present or absent by using POCUS compression of the central arteries. DISCUSSION: Using this technique, we found that a POCUS pulse check can be consistently performed in < 5 s and is clearly determinate, even when palpation yields indeterminate results. CONCLUSIONS: In this case series, the POCUS pulse check was a valuable adjunct that helped to change management for critically ill patients. Future prospective studies are required to determine the accuracy of this technique and the impact on patient outcomes in a larger cohort.

Oesophageal Doppler and calibrated pulse contour analysis are not interchangeable within a goal-directed haemodynamic algorithm in major gynaecological surgery.

BACKGROUND: Evidence for the benefit of an intraoperative use of a goal-directed haemodynamic management has grown. We compared the oesophageal Doppler monitor (ODM, CardioQ-ODM™) with a calibrated pulse contour analysis (PCA, PiCCO2™) with regard to assessment of stroke volume (SV) changes after volume administration within a goal-directed haemodynamic algorithm during non-cardiac surgery. METHODS: The data were obtained prospectively in patients with metastatic ovarian carcinoma undergoing cytoreductive surgery. During surgery, fluid challenges were performed as indicated by the goal-directed haemodynamic algorithm guided by the ODM. Monitors were compared regarding precision and trending. Clinical characteristics associated with trending were studied by extended regression analysis. RESULTS: A total of 762 fluid challenges were performed in 41 patients resulting in 1524 paired measurements. The precision of ODM and PCA was 5.7% and 6.0% (P=0.80), respectively. Polar plot analysis revealed a poor trending between ODM and PCA with an angular bias of -7.1°, radial limits of agreement of -58.1° to 43.8°, and an angular concordance rate of 67.8%. Dose of norepinephrine (NE) (scaled 0.1 µg kg(-1) min(-1)) [adjusted odds ratio (OR) 0.606 (95% confidence interval, CI: 0.404-0.910); P=0.016] and changes in mean arterial pressure (MAP) to a fluid challenge (scaled 10%) [adjusted OR 0.733 (95% CI: 0.635-0.845); P<0.001] were associated with trending between ODM and PCA, whereas there was no relation to type of i.v. solution. CONCLUSIONS: Despite a similar precision, ODM and PCA were not interchangeable with regard to measuring SV changes within a goal-directed haemodynamic algorithm. A decrease in interchangeability coincided with increasing NE levels and greater changes of MAP to a fluid challenge.

[24-Hour arterial pressure variability and 24-hour variability of pulse carries unidirectional character and is not associated with left ventricular hypertrophy (results of population study)].

Alternative prognostic interpretation of variability of arterial pressure (AP) and pulse seems contradictory if one considers classical conceptions of close physiological connection between AP and pulse. It is logical to expect that elevated variability of AP should be associated with elevated variability of pulse and vice versa. Within framework of the project EPOCH we examined a populational sample of inhabitants of Novosibirsk (129 men and 170 women) formed according to the family principle. Ambulatory 24-hour registration of AP and pulse was carried out with 15-30 minutes interval. Variability of AP turned out to be unidirectionally interconnected with variability of pulse and was not an independent marker of hypertrophy of the left ventricle but was associated with it at the account of concealed dependence on mean 24-hour AP. Cornell voltage index in persons with normal AP, "white coat" arterial hypertension (AH), "masked" AH was comparable and significantly lower than in subjects with sustained AH.

Human abuse potential and cognitive effects of taranabant, a cannabinoid 1 receptor inverse agonist: a randomized, double-blind, placebo- and active-controlled, crossover study in recreational polydrug users.

INTRODUCTION: Taranabant is a cannabinoid 1 receptor inverse agonist that was in development for treatment of obesity. Because of central nervous system effects, the study was performed to assess the abuse potential and cognitive effects of taranabant in recreational polydrug users compared with phentermine, dronabinol, and placebo. METHODS: Stimulant- and cannabis-experienced polydrug users (N = 30) were randomized in a double-blind crossover study to receive taranabant 2, 4, 10, and 20 mg; phentermine 45 and 90 mg; dronabinol 20 mg; and placebo. Subjective and neurocognitive measures were administered for 24 hours, and peak/peak change from baseline effects were analyzed using a linear mixed-effects model. RESULTS: Phentermine 45 and 90 mg showed abuse-related subjective effects versus placebo, including drug liking, overall drug liking, and other positive/stimulant effects, whereas dronabinol 20 mg showed abuse-related positive, cannabis-like, and sedative effects. Taranabant was not significantly different from placebo on most of the subjective measures other than negative/dysphoric effects at the highest dose, and its effects were significantly less pronounced relative to phentermine and dronabinol on most measures. Phentermine improved cognitive/motor performance and dronabinol impaired motor/cognitive performance on some measures, whereas taranabant 4 and 20 mg had minor impairment effects on manual tracking. CONCLUSIONS: The phentermine and dronabinol results demonstrate the validity and sensitivity of the study. Taranabant did not consistently show stimulant/cannabis-like effects or abuse potential in recreational polydrug users, indicating that cannabinoid 1 receptor inverse agonists/antagonists are unlikely to be recreationally abused.

[High-frequency oscillations in a pulse wave signal and their relation to differential blood count leucocytes].

High-frequency oscillations in a pulse wave signal in the range of 1-50 Hz and their relation to differential blood count leucocytes have been investigated. It is shown that the correlation coefficients grow in the frequency range of 1-12.5 Hz between high-frequency oscillations in a pulse wave signal and stab neutrophils, monocytes and segmented granulocytes. The procedure of smoothing the coefficients of harmonic variation has been proposed.

Ethnic differences in arterial wave reflections and normative equations for augmentation index.

Data regarding ethnic differences in wave reflections, which markedly affect the central pressure profile, are very limited. Furthermore, because age, heart rate, and body height are strong determinants of augmentation index, relating single measurements to normative data (in which augmentation index values correspond with average population values of its determinants) is challenging. We studied subject-level data from 10 550 adults enrolled in large population-based studies. In a healthy reference sample (n=3497), we assessed ethnic differences in augmentation index (ratio of second/first systolic peaks) and generated equations for adjusted z scores, allowing for a standardized comparison between individual augmentation index measurements and the normative population mean from subjects of the same age, sex, ethnic population, body height, and heart rate. After adjustment for age, body height, heart rate, and mean arterial pressure, African blacks (women: 154%; men: 138%) and Andean Hispanics (women: 152%; men: 133%) demonstrated higher central (aortic) augmentation index values than British whites (women: 140%; men: 128%), whereas American Indians (women: 133%; men: 122%) demonstrated lower augmentation index (all P<0.0001), without significant differences between Chinese and British whites. Similar results were found for radial augmentation index. Nonlinear ethnic/sex-specific equations for z scores were successfully generated to adjust individual augmentation index values for age, body height, and heart rate. Marked ethnic differences in augmentation index exist, which may contribute to ethnic differences in hypertensive organ damage. Our study provides normative data that can be used to complement the interpretation of individual hemodynamic assessments among men and women of various ethnic populations, after removing the effect of various physiological determinants.

Relation between the estimated glomerular filtration rate and pulse wave velocity in Japanese.

OBJECTIVE: We investigated the link between renal function as evaluated by estimated glomerular filtration rate (eGFR) and pulse wave velocity (PWV) in Japanese without medications. METHODS: A total of 1,244 Japanese subjects, aged 20-79 years, were recruited in a cross-sectional clinical investigation study. They received no medications. eGFR was calculated using serum creatinine (Cr), age and sex. Peripheral arterial stiffness was evaluated by brachial-ankle PWV (baPWV). RESULTS: eGFR and baPWV were significantly correlated with age. eGFR was negatively correlated with baPWV (men: r=-0.308, p<0.0001, women: r=-0.293, p<0.0001). Twenty-six men (5.6%) and 35 women (4.5%) were diagnosed as reduced eGFR (eGFR <60 mL/min/1.73 m(2)). We compared clinical parameters between subjects with reduced eGFR (Group R) and without such reduction (Group N). baPWV in Group R was significantly higher than that in Group N even after adjusting for age. In women, systolic blood pressure in Group R was also significantly higher than that in Group N. CONCLUSION: eGFR was closely associated with peripheral arterial stiffness in Japanese.

Evaluación longitudinal de la exploración del pie en una cohorte de pacientes con diabetes mellitus tipo 2 / Longitudinal evaluation of the foot examination in a cohort of patients with type 2 diabetes mellitus

Introducción: El pie diabético es un problema de salud frecuente y representauna causa importante de morbimortalidad. Objetivos: Analizar la evolución dela exploración de pies de pacientes diabéticos y determinar factores asociadosal desarrollo de pie patológico. Material y método: Estudio observacionalprospectivo en el que se incluyeron pacientes con diabetes tipo 2 seguidos enun centro de salud entre 2003 y 2008. Se recogieron datos sociodemográfi cos,clínicos y analíticos. Se realizó un análisis descriptivo de los datos de evaluacionessucesivas, y un análisis multivariante mediante regresión logística binariapara relacionar las variables con el desarrollo de pie patológico. Resultados: Seincluyeron 161 pacientes con una edad media de 66 años. Un 87% presentabahipertensión arterial, un 88% dislipemia, un 20% tenía antecedentes de enfermedadcardiovascular y un 11% de enfermedad vascular periférica. Un 9% presentabaretinopatía, un 21% neuropatía sintomática y un 0,6% antecedente deúlcera o amputación. En las evaluaciones anuales se objetivó una disminuciónde pulsos palpables (77,4% normales en la primera evaluación y 62,8% en lacuarta evaluación; p <0,0001), manteniéndose estable la sensibilidad al monofilamento (81,2-85,9%). El porcentaje de sujetos con pie de riesgo aumentó del30 al 42% (p <0,001), el de pie normal se mantuvo estable (de 39,5 a 42,3%)y el de pie patológico pasó del 30,6% en la primera evaluación al 23,1% en laúltima (p <0,01). Los niveles medios de HbA1c se mantuvieron alrededor de7,4% a lo largo de los 4 años. El análisis multivariante relaciona signifi cativamentecon pie diabético: edad avanzada, niveles elevados de HbA1c en la primeraevaluación, presencia de nefropatía al inicio del seguimiento, alteración basal enla exploración de pulsos, y menor número de puntos sensibles al monofi lamento(AU)

Conclusiones: Al fi nal del estudio se objetiva una disminución del porcentajede pies normales, fundamentalmente por la ausencia/disminución de los pulsos.El perfil de mayor riesgo para el desarrollo de pie diabético lo constituiría la personade mayor edad, con nefropatía, niveles elevados de HbA1c y alteracionesen la exploración (sensibilidad y/o pulsos distales)(AU)

Introduction: Diabetic foot is a frequent health problem and it represents animportant cause of morbidity and mortality. Objectives: To analyze the evolutionof foot examination in diabetic people and to determinate risk factors associatedwith diabetic foot. Material and methods: We performed an observationalprospective study. Patients with type 2 diabetes between the years2003-2008 and from a primary health care center were included. Measurements:sociodemographic, clinical data and test results. Descriptive analysisand logistic regression to relate the variables with development of diabetic footwere used. Results: 161 patients were included, with a mean age of 66years old. 87% of them had hypertension, 88% dyslipidemia, 20% had historyof cardiovascular disease and 11% of peripheral arterial disease. 9% hadretinopathy, 21% symptomatic neuropathy and 0.6% a history of ulcer or amputation.Successive annual assessments showed reduction of pedal pulsepalpation (77.4% normal at 1st evaluation and 62.8% at 4th evaluation, p<0.0001). Sensation in the feet kept stable (81.2-85.9%). Proportion of patientswith foot-at-risk increased from 30 to 42% (p <0.001), % of those withnormal foot did not change (from 39.5 to 42.3%) and % of those with pathologicdiabetic foot changed from 30.6% at first evaluation to 23.1% in the lastone (p <0.01). Mean HbA1c levels remained about 7.4% through the fouryears of follow-up. Multivariate analysis shows find a significant relationship ofdiabetic foot to advanced age, higher HbA1c levels at the beginning, presenceof nephropathy at first evaluation, basal alteration of pedal pulses, and a lownumber of sensitive points in the monofilament evaluation(AU)

Conclusions: Atstudy end, we observe a diminution of the proportion of healthy feet, basicallybecause of absence/deterioration of artery pulses. The patient with higher riskwould be an old patient, with nephropathy, high levels of HbA1c and alterationsin clinical evaluation (sensitivity and/or distant pulses)(AU)

Pulse contour cardiac output: an evaluation of the FloTrac method.

BACKGROUND AND OBJECTIVE: The aim of this study was to determine the agreement between pulmonary artery thermodilution (PA-TD) and a new pulse contour method (PCM), FloTrac/Vigileo version 1.0, and to asses the ability of FloTrac to track sudden changes in cardiac output. METHODS: Cardiac output was determined twice after induction of anaesthesia, but before cardiac surgery, with both PA-TD and a PCM in order to determine the precision of both methods. The bias and agreement between the two methods were calculated using Bland-Altman analysis. Postoperatively, in patients with heart rates under 60 beats min(-1), atrial pacing was initiated and cardiac output was determined before and after with both methods. RESULTS: Twenty-five patients were investigated. The precisions of PA-TD and the PCM were 0.35 (95% confidence interval +/-0.12) and 0.6 l min(-1) (95% confidence interval +/-0.21%). The bias between PA-TD and the PCM was -0.51 l min(-1) and the limits of agreement were +/-1.87 l min(-1) (95% confidence interval +/-0.39 and +/-0.66). The percentage error was 48%. The changes in cardiac output with atrial pacing were in the same direction in all nine patients. CONCLUSION: In this study, agreement between PA-TD and the PCM was poor, but the PCM was able to track the direction of pace-induced changes in cardiac output.

The validity of finger pulse line length for the detection of concealed information.

Building on the orienting theory of the Concealed Information Test, Elaad and Ben-Shakhar [Elaad, E., & Ben-Shakhar, G. (2006). Finger pulse waveform length in the detection of concealed information. Int. J. Psychophysiol., 61, 226-234.] proposed a new measure for the detection of concealed information: finger pulse line length (FPLL). This measure is recorded with a plethysmograph and combines pulse rate and pulse amplitude. Because the validity of finger pulse amplitude is still not established, one could question the benefits of FPLL to well validated measures such as heart rate. In the present study we compared the validity of FPLL, finger pulse rate and finger pulse amplitude in the detection of concealed information. Male community volunteers (n=77) who had acquired crime knowledge through a mock crime procedure, were instructed to deny knowledge in a Concealed Information Test. Skin conductance, finger pulse line length, finger pulse rate and amplitude, heart rate and respiration were recorded. FPLL validity was significantly higher than that of finger pulse amplitude and heart rate. These data, together with its ease of measurement, support the use of FPLL.

Reliability of pulse palpation by healthcare personnel to diagnose paediatric cardiac arrest.

AIM: To determine the reliability of pulse palpation to diagnose paediatric cardiac arrest. MATERIALS AND METHODS: With all cardiovascular information obscured, 209 doctors and nurses (rescuers) were requested once each to determine if a pulse was present in 1 of 16 infants and children (average age 1.8 years, range 1 week-13 years) provided with non-pulsatile circulation with veno-arterial extracorporeal membrane oxygenation or left ventricular assistance for cardiac arrest or failure. Rescuers did not know the stage of recovery of the heart and did not if a true pulse was present or absent. Rescuer decisions "pulse absent" or "pulse present" were compared with concurred decisions of investigators and bedside nurse who knew cardiovascular data and had unlimited time to palpate pulses. RESULTS: Rescuer pulse palpation accuracy was 78% (95% CI 70-82), sensitivity 0.86 (95% CI 0.77-0.90) and specificity 0.64 (95% CI 0.53-0.74). When investigators diagnosed cardiac arrest pulse pressure was 6+/-5mmHg (range 0-20) compared with 9+/-8mmHg (range 0-29) with rescuers (p=0.0004). With pulse pressure zero, rescuer accuracy was 89% and sensitivity 0.89. Sixty per cent of rescuers chose a brachial pulse, 33% a femoral pulse with respective accuracies of 78% and 77%, sensitivities 0.86 and 0.85 and specificities 0.67 and 0.56. CONCLUSIONS: Pulse palpation is unreliable to diagnose paediatric cardiac arrest. Rescuers misdiagnose on 22% of occasions and which may lead them to withhold external cardiac compression on 14% of occasions when needed and on 36% to give it when not needed. Brachial palpation is slightly more reliable than femoral palpation.

[Cardiac output determination by thermodilution and arterial pulse waveform analysis in patients undergoing aortic valve replacement].

PURPOSE: To compare the accuracy of cardiac output (CO) measurement by arterial pulse waveform analysis (CO(PW)) to thermodilution assessments in patients with aortic stenosis, a high-risk patient group who may benefit from extended hemodynamic monitoring. METHODS: In 30 patients with aortic stenosis, CO was assessed in triplicate by thermodilution via pulmonary artery catheterization (CO(PAC)), and by arterial pulse waveform analysis (CO(PW)), before and after valve replacement. The techniques were compared by assessing the repeatability coefficient of each method and by calculating the percentage error, bias, and the limits of agreement between methods. RESULTS: The repeatability coefficients of CO(PAC) and CO(PW) were 0.89 L.min(-1) and 1.04 L.min(-1) respectively after induction of anesthesia, which corresponded to 24% of CO(PAC) and 26% of CO(PW), and increased to 33% of CO(PAC) and 32% of CO(PW) immediately after extracorporeal circulation. A systematic error between methods was not observed. The limits of agreement were bias +/- 1.42 L.min(-1) after anesthesia induction, corresponding to a 36% percentage error. The scattering of differences between methods increased markedly after termination of extracorporeal circulation (percentage error 56%). CONCLUSION: The repeatability of CO(PAC), as well as of CO(PW), is reduced in patients with aortic stenosis. The repeatability of both methods, as well as the agreement between methods, decreased markedly immediately after termination of cardiopulmonary bypass.

Reproducibility of pulse-wave analysis and pulse-wave velocity determination in chronic kidney disease.

BACKGROUND: Indices of central arterial stiffness, derived by use of applanation tonometry, have shown to be strong independent predictors of cardiovascular morbidity and mortality in patients with chronic kidney disease (CKD). The objective of this study was to evaluate the intra- and inter-observer and day-to-day reproducibility of pulse-wave analysis (PWA) and pulse-wave velocity (PWV) in pre-dialysis patients with CKD stages 3-5 using applanation tonometry with the SphygmoCor software and hardware. METHODS: Double recordings of the radial pressure waveform and the aortic and brachial PWV were performed under standardized conditions in 19 CKD patients with a mean GFR 25.3 ml/min/1.73 m(2) (range 9.9-42.2) by two trained observers and repeated by one of the observers within a week. RESULTS: The mean inter-observer and day-to-day differences (+/-2 SD) for the augmentation index (AIx) were 0.9 +/- 15.8% and 2.6 +/- 11.2%, for subendocardial viability ratio (SEVR) -0.9 +/- 15.5% and -0.4 +/- 24.7%, for aortic pulse pressure (PP) 1.4 +/- 13.3 mmHg and 0.3 +/- 20.9 mmHg and for aortic PWV 0.3 +/- 3.2 m/s and -0.7 +/- 1.9 m/s, respectively. Intra-observer differences were calculated for each of three sets of double measurements and showed good reproducibility as well. Calculations on sample size needed in a clinical trial showed a limited number of patients needed in a clinical study over time. CONCLUSIONS: PWA and PWV based on applanation tonometry using the SphygmoCor software and hardware are highly reproducible in pre-dialysis patients with CKD with the day-to-day variation being in accordance with the intra- and inter-observer variation. Thus, applanation tonometry using the SphygmoCor system is a simple, non-invasive method to assess central haemodynamics in clinical trials in patients with pre-dialysis CKD with only a limited number of patients needed to detect significant differences.

Continuous cuff-less blood pressure monitoring based on the pulse arrival time approach: the impact of posture.

There is an unmet need for cuff-less blood pressure (BP) monitoring especially, in personal healthcare applications. The pulse arrival time (PAT) approach might offer a suitable solution to enable comfortable BP monitoring even at beat-level. However, the methodology is based on hemodynamic surrogate measures, which are sensitive to patient activities such as posture changes, not necessarily related to blood pressure variations. In this paper, we analyze the impact of posture on the PAT measure and related hemodynamic parameters such as the pre-ejection period in well-defined procedures. Additionally, the PAT of a monitored subject is investigated in an unsupervised scenario illustrating the complexity of such a measurement. Our results show the failure of blood pressure inference based on simple calibration strategies using the PAT measure only. We discuss opportunities to compensate for the observed effects towards the realization of wearable cuff-less blood pressure monitoring. These findings emphasize the importance of accessing context information in personal healthcare applications, where vital sign monitoring is typically unsupervised.

Normality of upper and lower peripheral pulse transit time of normotensive and hypertensive children.

OBJECTIVES: The ankle-brachial index (ABI) is known to be indicative of sub-clinical peripheral arterial diseases that are correlated with cardiovascular disease risk factors like atherosclerosis or ischemic extremity. Due to its occluding measurement nature, this may not be appealing to less cooperative patients when multiple prolonged screening is required. A simple and non-intrusive approach termed pulse transit time ratio (PTTR) has recently shown to be potential surrogate marker for the prolonged ABI measurement. Other studies have also suggested that subjects with hypertension have stiffer arterial wall and thereby can confound transit time related parameters. Thus, it becomes important to understand the PTTR normality and difference of hypertensive children when compared to those measured from normotensive children. METHODS: About 55 normotensive (39 male; aged 8.4 +/- 2.3 yr) and 4 hypertensive (4 male; aged 5-10 yr) Caucasian children were recruited from the same geographical location. A customized device was used to compute pulse transit time related measurements. Since the PTTR approach produced a delta value that was similar to that of ABI, possible inter-subject physiologic differences had limited confounding effects on the derived PTTR parameter. RESULTS: The obtained transit time measurements from the hypertensive children had lower pulse transit time value when compared to their normotensive counterparts. However, the statistical analysis indicated that they had insignificant PTTR difference (p > 0.01) from those seen in the normotensive children. CONCLUSIONS: The findings herein suggest that stiffer arterial wall may have confounding effects on the derived transit time related measurements but it is limited on the PTTR parameter. Similar to the ABI approach, PTTR may be only confounded by abnormal local changes in either of the measured peripheral arterial wall. Hence, the PTTR technique shows promise to be an ABI marker from this perspective.

Repeatability of the measurement of augmentation index in the clinical assessment of arterial stiffness using radial applanation tonometry.

OBJECTIVE: Aortic augmentation index (AIx) measured using applanation tonometry is a non-invasive indicator of arterial stiffness. The objective of this study was to assess its repeatability when used by nurses with limited experience of the technique. MATERIAL AND METHODS: Blood pressure/augmentation index (BP/AIx) was measured 4 times in 20 consecutive ambulant patients (16 male) after they rested supine for 15 min. Two nurses independently and alternately measured BP/AIx using the same equipment (Omron HEM-757; SphygmoCor with Millar hand-held tonometer). Nurses were blinded to patient medical records and their colleague's AIx/BP. 'Within' and 'between' observer differences were assessed using intra-class correlation coefficients (rI) and 95 % limits of agreement (95 % LoA) derived from Bland-Altman plots. RESULTS: Mean age was 56 (mean BP 136/79; mean pulse 64). Mean AIx was 24.1 (range 2.8 to 41.0). Both 'between' and 'within' observer repeatability was very high, with intra-class correlation coefficients ranging from 0.92 to 0.98. Mean AIx readings 'between' observers differed by only 0.68 (95 % CI -0.24 to 1.59) with a high rI (0.98; 95 % CI 0.95 to 0.99) and a narrow 95 % LoA (-3.22 to 4.57). The 95 % LoA for 'within' observer repeatability was -6.75 to 7.95. Differences in AIx measurement did not vary over time or with increasing levels of AIx. CONCLUSIONS: Even when undertaken by relatively inexperienced operators, both 'within' and 'between' observer repeatability of AIx measurement is very high. Such non-invasive assessment of arterial stiffness has the potential to be included in the clinical assessment of ambulant patients.

Baseline wander correction in pulse waveforms using wavelet-based cascaded adaptive filter.

Pulse diagnosis is a convenient, inexpensive, painless, and non-invasive diagnosis method. Quantifying pulse diagnosis is to acquire and record pulse waveforms by a set of sensor firstly, and then analyze these pulse waveforms. However, respiration and artifact motion during pulse waveform acquisition can introduce baseline wander. It is necessary, therefore, to remove the pulse waveform's baseline wander in order to perform accurate pulse waveform analysis. This paper presents a wavelet-based cascaded adaptive filter (CAF) to remove the baseline wander of pulse waveform. To evaluate the level of baseline wander, we introduce a criterion: energy ratio (ER) of pulse waveform to its baseline wander. If the ER is more than a given threshold, the baseline wander can be removed only by cubic spline estimation; otherwise it must be filtered by, in sequence, discrete Meyer wavelet filter and the cubic spline estimation. Compared with traditional methods such as cubic spline estimation, morphology filter and Linear-phase finite impulse response (FIR) least-squares-error digital filter, the experimental results on 50 simulated and 500 real pulse signals demonstrate the power of CAF filter both in removing baseline wander and in preserving the diagnostic information of pulse waveforms. This CAF filter also can be used to remove the baseline wander of other physiological signals, such as ECG and so on.

Finger pulse waveform length in the detection of concealed information.

An attempt was made to assess the efficiency of the finger pulse waveform length (FPWL), in detection of concealed information. For this purpose, two mock-theft experiments were designed. In the first, 40 guilty participants were examined while electrodermal, respiration and finger pulse volume were recorded. Results showed that detection accuracy with the FPWL was at least as good as the accuracy obtained with the other two measures (respiration changes and skin conductance responses). Detection efficiency was further improved when a combination of FPWL with the other two measures was used. In the second experiment, 39 guilty and 23 innocent participants were instructed to deny knowledge while the transducers were not attached to them. Then, the same questions were repeated while electrodermal, respiration and finger pulse volume were recorded. Results showed reduced rates of identification compared to the first experiment, which were explained by habituation. However, finger pulse was less affected by habituation than both respiration and skin conductance. Results suggested that the FPWL might be a useful addition to the existing measures in the detection of concealed information.

Weight gain during treatment of bipolar I patients with olanzapine.

BACKGROUND: Body weight increase during long-term treatment with olanzapine in schizophrenia patients is well documented, but weight gain and its association with other medical measures are less well evaluated in bipolar disorder patients. METHOD: We analyzed data from a 3-week, randomized, placebo-controlled trial of olanzapine for acute mania in DSM-IV bipolar I patients, followed by open continuation treatment with olanzapine up to a year. We examined factors associated with increased body mass index (BMI), including ratings of clinical change and selected physiologic measures. RESULTS: Among 113 subjects treated with olanzapine for a mean +/- SD of 28.6 +/- 19.9 weeks, BMI increased from a baseline mean of 28.8 +/- 6.2 kg/m(2), by 7.9 +/- 10.8% (p < .001), into the obese range (31.0 +/- 6.1 kg/m(2)). Initial BMI change (first 3 weeks of drug exposure) predicted final BMI increases (Spearman rank correlation r(s) = 0.32, p < .001). History of longer illness (p = .006) and lifetime substance abuse (p = .02) were associated with below-median BMI increases. BMI increased much more among 40 subjects achieving symptomatic recovery than in the 73 who did not (by 11.9 +/- 13.2% vs. 5.3 +/- 7.7%; p = .004), with correspondingly longer olanzapine exposure (44.7 +/- 11.8 vs. 19.7 +/- 17.7 weeks; p < .001) at similar doses. On average, serum cholesterol increased 4.8 times more (17.5% vs. 3.6%) and endpoint cholesterol levels were newly 240 mg/dL or greater 3.6 (95% CI = 1.5 to 8.0) times more frequently in subjects with above-median BMI gain, who also experienced significantly larger increases in systolic and diastolic blood pressure, pulse rates, and nonfasting serum glucose than low-BMI-gain subjects. CONCLUSIONS: Weight gain associated with long-term olanzapine treatment for mania was common, substantial, time-dependent, predicted by initial increases, and temporally associated with significant changes in cardiovascular and metabolic measures in bipolar I patients with prolonged illness and already-high basal BMI. An association of weight gain with favorable clinical response probably reflects longer olanzapine treatment.