MS

thesisMean arterial blood pressures were measured peripherally in the upper and lower positions of the right leg, right arm, and left arm by a neonate oscillometric blood pressure machine. They also were compared to the mean arterial pressures measured centrally by an umbilical artery catheter or radial arterial line. The study consisted of 10 infants (3 males, 7 females) 1,200 grams or less. Measurements were obtained in each infant for 3 consecutive days. The data collected were analyzed by computer statistical analysis. The analysis revealed that day and day by location were significant. However, the standard deviations were so great that further analysis was not continued. The physiological significance of these findings was discussed. In order to obtain a correct clinical evaluation, the importance of knowing these physiological variances of blood pressure in infants was stressed

Optimal schedule for home blood pressure measurements and clinical significance of the variability in home-measured blood pressure and heart rate

Siirretty Doriast

Optimizing the Electrocardiogram and Pressure Monitoring

journal articleBiomedical Informatic

Mobile Personal Healthcare System for Non-Invasive, Pervasive and Continuous Blood Pressure Monitoring: A Feasibility Study

Background: Smartphone-based blood pressure (BP) monitor using photoplethysmogram (PPG) technology has emerged as a promising approach to empower users with self-monitoring for effective diagnosis and control ofhypertension (HT). Objective: This study aimed to develop a mobile personal healthcare system for non-invasive, pervasive, and continuous estimation of BP level and variability to be user-friendly to elderly. Methods: The proposed approach was integrated by a self-designed cuffless, calibration-free, wireless and wearable PPG-only sensor, and a native purposely-designed smartphone application using multilayer perceptron machine learning techniques from raw signals. We performed a pilot study with three elder adults (mean age 61.3 ± 1.5 years; 66% women) to test usability and accuracy of the smartphone-based BP monitor. Results: The employed artificial neural network (ANN) model performed with high accuracy in terms of predicting the reference BP values of our validation sample (n=150). On average, our approach predicted BP measures with accuracy \u3e90% and correlations \u3e0.90 (P \u3c .0001). Bland-Altman plots showed that most of the errors for BP prediction were less than 10 mmHg. Conclusions: With further development and validation, the proposed system could provide a cost-effective strategy to improve the quality and coverage of healthcare, particularly in rural zones, areas lacking physicians, and solitary elderly populations

Accuracy of automated blood pressure measurements in the presence of atrial fibrillation: systematic review and meta-analysis

This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordAtrial fibrillation (AF) affects ~3% of the general population and is twice as common with hypertension. Validation protocols for automated sphygmomanometers exclude people with AF, raising concerns over accuracy of hypertension diagnosis or management, using out-of-office blood pressure (BP) monitoring, in the presence of AF. Some devices include algorithms to detect AF; a feature open to misinterpretation as offering accurate BP measurement with AF. We undertook this review to explore accuracy of automated devices, with or without AF detection, for measuring BP. We searched Medline and Embase to October 2018 for studies comparing automated BP measurement devices to a standard mercury sphygmomanometer contemporaneously. Data were extracted by two reviewers. Mean BP differences between devices and mercury were calculated, where not reported and compared; meta-analyses were undertaken where possible. We included 13 studies reporting 14 devices. Mean systolic and diastolic BP differences from mercury ranged from −3.1 to + 6.1/−4.6 to +9.0 mmHg. Considerable heterogeneity existed between devices (I 2 : 80 to 90%). Devices with AF detection algorithms appeared no more accurate for BP measurement with AF than other devices. A previous review concluded that oscillometric devices are accurate for systolic but not diastolic BP measurement in AF. The present findings do not support that conclusion. Due to heterogeneity between devices, they should be evaluated on individual performance. We found no evidence that devices with AF detection measure BP more accurately in AF than other devices. More home or ambulatory automated BP monitors require validation in populations with AF.National Institute for Health Research (NIHR

Significantly Reduced Blood Pressure Measurement Variability for Both Normotensive and Hypertensive Subjects: Effect of Polynomial Curve Fitting of Oscillometric Pulses

This study aimed to compare within-subject blood pressure (BP) variabilities from different measurement techniques. Cuff pressures from three repeated BP measurements were obtained from 30 normotensive and 30 hypertensive subjects. Automatic BPs were determined from the pulses with normalised peak amplitude larger than a threshold (0.5 for SBP, 0.7 for DBP, and 1.0 for MAP). They were also determined from cuff pressures associated with the above thresholds on a fitted curve polynomial curve of the oscillometric pulse peaks. Finally, the standard deviation (SD) of three repeats and its coefficient of variability (CV) were compared between the two automatic techniques. For the normotensive group, polynomial curve fitting significantly reduced SD of repeats from 3.6 to 2.5 mmHg for SBP and from 3.7 to 2.1 mmHg for MAP and reduced CV from 3.0% to 2.2% for SBP and from 4.3% to 2.4% for MAP (all P<0.01). For the hypertensive group, SD of repeats decreased from 6.5 to 5.5 mmHg for SBP and from 6.7 to 4.2 mmHg for MAP, and CV decreased from 4.2% to 3.6% for SBP and from 5.8% to 3.8% for MAP (all P<0.05). In conclusion, polynomial curve fitting of oscillometric pulses had the ability to reduce automatic BP measurement variability

Observation of the pulse oximeter trace to estimate systolic blood pressure during spinal anaesthesia for Caesarean section: the effect of body mass index

Background: The estimation of systolic blood pressure by disappearance and reappearance of the pulse oximeter trace during cuff inflation and deflation was compared with non-invasive blood pressure (NIBP) measurement, across the range of body mass index (BMI), during spinal anaesthesia for Caesarean section.Methods: Seventy-five parturients were recruited, with BMI of &lt; 30 (Group 1), 30–40 (Group 2), and &gt; 40 kg/m2 ((morbidly obese, Group 3). A non-invasive blood pressure monitor was used with the pulse oximeter probe on the ipsilateral arm. Estimations were done before induction and 5 min after induction of spinal anaesthesia, during cuff inflation and deflation. Bland and Altman analysis was performed and the concordance correlation coefficient (r) estimated.Results: For estimation of systolic blood pressure during cuff inflation under spinal anaesthesia in Groups 1, 2 and 3: r = 0.57, 0.74 and 0.91; bias = –0.4, –2.9 and 0.8 mmHg, and limits of agreement = –27.7 to 26.9, –27.7 to 21.9, and –15.9 to 17.5 mmHg respectively. The mean (SD) time saved by estimation during inflation compared with measurement in Groups 1, 2 and 3 was 22.8 (13.2) s, 30.0 (11.6) s and 33.0 (15.6) s respectively. In Group 3, the percentage error was ± 13% of mean systolic blood pressure.Conclusions: Estimation of systolic blood pressure during cuff inflation under spinal anaesthesia in the morbidly obese is more precise than in lower BMI parturients. Time to estimation is relevantly shorter than measurement. This could improve patient safety by rapid and accurate identification of hypotension in these high-risk patients. This estimation method is associated with limits of agreement that may be clinically significant even in morbidly obese patients, and should not be considered a replacement for subsequent NIBP measurement.Keywords: body mass index, Caesarean section, pulse oximeter trace, spinal anaesthesia, systolic blood pressur

Non-Invasive Blood Glucose, Blood Pressure, Heart Rate and Body Temperature Monitoring Device

The race for the next generation of painless and reliable glucose& BP monitoring for patients is on. As technology advances, both diagnostic techniques and equipment improve. Advancements in medical device technology have allowed physicians to treat their patients better, saving lives and promoting continuous improvements in the quality of life for billions of people around the globe. This paper also aims to develop the device mostly but not limiting to the rural population of the country who hardly have access to good physicians for diagnosis and make it cost efficient. This paper first examines the various available technologies and then states our idea behind implementing a device capable of measuring 4 important medical parameters, which are glucose, blood pressure, heart rate and body temperature. However, all these techniques are non-invasive meaning the usage doesn?t depend on taking out blood from the body but uses sensors to compute all the 4 parameters. The device is also capable of sending all the computed data to the doctor via SMS using SIM900 communication module