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Objective To develop a method for monitoring unconstrained sleep respiration suitable for daily use at home, so as to realize high precision screening of sleep apnea syndrome (SAS) or other respiratory diseases without affecting normal sleep. Methods A new unconstrained measurement method using sheet-type flexible pressure sensor was proposed. This method could obtain the information of respiratory motions of the chest and abdomen by measuring the pressure fluctuations of the chest and abdomen acting on the mattress. Experiments were conducted on ten healthy subjects to confirm effectiveness of the proposed method by comparing the result of the unconstrained measurement and those of respiratory inductance plethysmography (RIP) using band sensors, respectively. Results Sheet-type flexible pressure sensor could measure the pressure fluctuations of the chest and abdomen acting on the mattress during respiration and obtain respiratory waveform and respiratory rate. The respiratory rate measured with the sheet-type flexible pressure sensor agreed with those obtained by RIP. The gender and the lying position greatly affected whether the phases of the pressure fluctuations of the chest and abdomen measured with the flexible sensor differed from those obtained by RIP. The chest respiratory finite element model was established to analyze the phase difference of respiratory movement. Conclusions Sheet-type flexible pressure sensor is effective to monitor unconstrained sleep respiration, indicating the potential to identify the SAS types. But further researches of motion decoupling are required to identify the phase difference between the chest motion and the abdomen motion, which are coupled with each other.
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Objective : To explore the correlation between blood pressure fluctuation and chronic kidney disease-mineral and bone disorder (CKD-MBD) in patients with maintenance hemodialysis (MHD). Methods ¡¤ From Jan. 2009 to Apr. 2015, 433 MHD patients in Hemodialysis Center of Renji Hospital, Shanghai Jiao Tong University School of Medicine were included, and their clinical data, treatment parameters during dialysis, lab examination indexes and drug applications were collected. According to the difference value of systolic blood pressure (SBP) during dialysis period, all the patients were divided into high fluctuation group of blood pressure (|△ SBP| ≥ 10 mmHg, n=234) and low fluctua-tion group of blood pressure (|△ SBP|<10 mmHg, n=199). The blood pressure fluctuation and its relationship with dialysis adequacy, bone metabolism indicator and nutrition indicator were analyzed between the two groups. Results ¡¤ Compared with the low fluctuation group of blood pressure, the patients in the high fluctuation group of blood pressure took higher proportion of β receptor blockers and Vit D, higher level of serum P and intact parathyroid hormone (iPTH), higher dialysis age, and lower Kt/V, ultrafiltration volume, body mass index (BMI) and serum albumin (ALB) level (all P<0.05). The blood pressure fluctuation between the patients with different serum P and iPTH levels was statistically significant (all P<0.05). There was no statistically significant difference in blood pressure fluctuation between the patients with different serum Ca levels. Multivariate Logistic regression analysis showed that dialysis age, serum P and iPTH levels were independent risk factors for blood pressure fluctuation of MHD patients, while Kt/V and ALB were protective factors. Con-clusion ¡¤ Blood pressure fluctuation in MHD patients during dialysis period is significantly correlated with CKD-MBD, nutritional status, dialy-sis age and dialysis adequacy.
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Characterizing the time course of baseline or pre-drug blood pressure is important in acquiring unbiased estimates of antihypertensive drug effect. In this study, we recruited 23 healthy male volunteers and measured systolic (SBP) and diastolic blood pressure (DBP) over 24 hours on an hourly basis. Using a non-linear mixed effects model, circadian rhythm observed in blood pressure measurements was described by incorporating two cosine functions with periods 24 and 12 hours. A mixture model was applied to identify subgroups exhibiting qualitatively different circadian rhythms. Our results suggested that 78% of the study population, defined as ‘dippers’, demonstrated a typical circadian profile with a morning rise and a nocturnal dip. The remaining 22% of the subjects defined as ‘non-dippers’, however, were not adequately described using the typical profile and demonstrated an elevation of blood pressure during night-time. Covariate search identified weight as being positively correlated with mesor of SBP. Visual predictive checks using 1,000 simulated datasets were performed for model validation. Observations were in agreement with predicted values in ‘dippers’, but deviated slightly in ‘non-dippers’. Our work is expected to serve as a useful reference in assessing systematic intra-day blood pressure fluctuations and antihypertensive effects as well as assessing drug safety of incrementally modified drugs.
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Humans , Male , Blood Pressure , Circadian Rhythm , Dataset , VolunteersABSTRACT
Objective To analyze the feasibility and safety in application of resectoscope combined with laparoscopy in the operation treatment of paraganglioma of urinary bladder.Methods 7 cases patients with paraganglioma of urinary bladder treated in our hospital from November 2014 to August 2018 were analyzed retrospectively.There were 5 males and 2 females,average age of 31.1 years (22-37 years),average body mass index was 22.3 kg/m2 (18.3-22.5 kg/m2).All the 7 cases patients complained of dizziness and palpitation after urination,average basal systolic blood pressure was 111.8 mmHg (97-124 mmHg),the average fluctuation of systolic blood pressure before and after urination was 64.9 mmHg(28-91 mmHg),the CT and cystoscopy prompt bladder tumor,the average diameter was 2.7 cm(2.1-3.5 cm).The average of plasma norepinephrine was 706.3 pg/ml(330-997 pg/ml);the average of plasma dopamine was 101.1 pg/ml(44-145 pg/ml);the average of 24h urinary vanilmandelic acid was 13.4 mg/24h (10.3-16.1 mg/24h).All the patients has controlled the blood pressure and dilate the blood vessels with phenoxybenzamine hydrochloride,accepted the operation of resectoscope combined with laparoscopy partial cystectomy and bladder sutura per abdomen after ample dilatancy.The patients had lithotomy position with trendelenburg,preparation of gas peritoneal cavity by transabdominal,inside the resectoscope by transurethral at the same time,mutilated bladder mucosa beside 1cm at the edge of the tumor,and cut full thickness bladder wall,take the extraperitional fat as the standard procedure;we could see the cutting edge clear at this time by laparoscopy,cut off the pelvic peritoneum,extraperitional fat and the tumor.The sample placed in bladder,close the bladder with absorbable or barbed wires,take out the sample by resectoscope.Results All the 7 cases patients operation was successfully completed,no cases has been transfered to open.The average time of operation is 85.3 min(65-100 min),the average amount of bleeding is 27.9 ml(10-50 ml).The average fluctuation of systolic blood pressure is 8.7 mmHg(6-15 mmHg).Bladder washout was stopped 24h after operation,catheter was removed 1 weeks after operation.There is no obvious complications occurred.The average hospital stay is 3.7 days (3-5 days).The average pain score of 4 cases 4h after operation is 3.8 (2-5),reevaluation 24h after operation is 2.3 (1-4).The average follow-up time is 7.9 months(2-15 months).All the 7 cases patients clinical symptoms disappeared,there is no fluctuation of systolic blood pressure before and after urination,there is no recurrence of the tumor.Conclusions To the paraganglioma of urinary bladder in fundus of bladder or anterior wall of bladder,we can accurate resection tumor by resectoscope combined with laparoscopy,reduce blood pressure fluctuations,reduce the surgical trauma and the distress of patients.It is a safety and effective minimally invasive surgery.
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PURPOSE: To investigate the postural change of intraocular pressure (IOP) from sitting to supine position and determine the relationship to other ocular parameters including ocular pulse amplitude (OPA) in glaucoma suspect and open angle glaucoma patients. METHODS: The present study included 46 eyes of 46 patients. First, we measured IOP and OPA using Goldmann applanation tonometer (GAT), Pascal dynamic contour tonometer and TonoPen(R). Using TonoPen(R), the IOP was measured immediately after the subjects were placed in a supine position and 10 minutes and 30 minutes thereafter. We also investigated the correlation between positional change of IOP and axial length (AL), refractive error (RE), and OPA. RESULTS: IOPs of patients in a sitting position measured with GAT and TonoPen(R) were 15.3 +/- 3.3 mm Hg and 16.6 +/- 2.9 mm Hg, respectively, and OPA was 2.57 +/- 0.89 mm Hg. IOPs measured with TonoPen(R) were 17.6 +/- 2.9 mm Hg immediately after position change, 18.2 +/- 3.7 mm Hg after 10 minutes and 17.5 +/- 2.7 mm Hg after 30 minutes. Each IOP change was statistically significant and the largest change was after 10 minutes. Changes of IOP after 10 minutes were positively correlated with OPA (R = 0.340) and RE (R = 0.330) and negatively correlated with AL (R = -0.410). CONCLUSIONS: When placed in a supine position, the IOP of patients increased and then decreased over time. Positional IOP change was influenced by AL and OPA and variable hemodynamic factors and apparently influenced OPA and ocular perfusion pressure.
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Humans , Glaucoma , Glaucoma, Open-Angle , Hemodynamics , Intraocular Pressure , Perfusion , Refractive Errors , Supine PositionABSTRACT
This study was undertaken to clarify the influence of respiratory blood pressure variability upon the relationship between respiratory period and respiratory cardiac cycle variability. In 4 healthy male university students respiratory period was varied over the range of 6-20 sec while tidal volume was maintained constant (21) and in 5 other male students tidal volume was varied over the range of 1.0-2.5<I>l</I> while respiratory period was maintained constant (6 sec) . For cardiac cycle (RR) and systolic and diastolic blood pressure (SBP and DBP), amplitude of respiratory variability and phase difference between respiratory variability and respiration were measured.<BR>1. Patterns of change of amplitude of RR and of SBP were similar when respiratory period was changed.<BR>2. When respiratory period was short (6sec), RR was nearly in phase with SBP. However, as respiratory period increased, the phases of RR and SBP had a tendency to proceed, with the tendency being more pronounced in the latter. Thus, when respiratory period was prolonged (20 sec), SBP led RR.<BR>3. Phase relationship between respiratory SBP variability and respiration did not change when tidal volume was changed.<BR>4. Respiratory DBP variability became more marked as respiratory period increased, and showed more marked phase shift than did respiratory SBP variability. Therefore, of those parameters DBP occurred earlier.<BR>Based on these results, it is concluded that respiratory RR variability is closely related to respiratory SBP variability when respiratory period is changed, but that the phase difference between RR and SBP reflects the effect of pulmonary stretch reflex which is dependent on respiratory period.
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Many trials to get informations from arterial waveforms have been done. But it was not so simple as expected because of normally fluctuating characteristics of arterial waveform due to respiration, extracardiac neuro-humoral control, etc. By using power spctral analysis we can figure out powers of these extrinsic contribting factors as well as contours of individual pulse wave by harmonic analysis. The purpose of this study is to compare the results of power spectral analysis and some basic parameters of arterial waveform before and after anesthesia to establish the basic changes during halothane anesthesia. The analog informations, obtained from patients undergoing operation with radial artery cannulated for continuous monitoring, was obtained from analog output of the Cardiocap monitor. It was transformed to digital information by A/D converter and saved to IBM compatible computer with mathcoprocessor. The data was processed offline by the signal analysis software DADiSP version 1.05 with the same computer. Results of mean arterial pressure, heart rate, dp/dt, low frequency peak, high frequency peak and harmonic pulse contour analysis were compared before and after anesthesia. We could conclude that halothane anesthesia diminishes all powers of harmonic components of arterial wave and powers of extrinsic components that affect low frequency area.