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91.
多普勒超声心动图评估左心室舒张末压的研究   总被引:1,自引:0,他引:1  
目的探讨多普勒超声心动图评估左室舒张末压的有效方法与指标。方法对68例病人采用左心导管测压及经胸多普勒超声心动图检测。结果对比研究显示,联合肺静脉与二尖瓣血流频谱分析优于二尖瓣血流频谱分析,肺静脉A峰和二尖瓣A峰时限差值(PAd-Ad)与左室舒张末压实测值呈最佳相关性(r=0.72,P<0.01)。结论认为应用多普勒超声心动图测定PAd与Ad,并以其差值估测左室舒张末压,是一项简便、可靠的无创性评估左室舒张末压的方法。PAd-Ad≥0可作为临床判断左室舒张末压增高[≥2.0kPa(15mmHg)]的一项半定量指标。  相似文献   
92.
对862例心血管疾病介入诊治术患者术前分别采用心理护理(n=431)和非心理护理(n=431)前后比较心理状态差别观察。结果显示:手术前所有患者均有严重焦虑心理,经采用心理宣教、心理护理后,患者焦虑程度大大降低(P<0.001),处于接受手术的最佳心理状态,保证手术顺利进行,并减少了术前、中、后并发症的发生。而未行心理宣教及心理护理的患者的焦虑程度几乎没有变化(P>0.05),有的甚至提高。通过对照观察、心理宣教及心理护理的有效实施,对消除患者的焦虑、恐惧心理有较满意的效果,并能达到仅靠操作技术难以获得的效果,起到良好的助手作用。  相似文献   
93.
OBJECTIVE: The study was designed to assess cardiovascular risk factorsin marathon runners with different degrees of fitness. DESIGN: A total of 30 male middle-aged marathon runners were dividedaccording to their marathon running time into fit (265 ±8 min), fitter (222 ± 5 min) and fittest (178 ±12 min). The three groups of 10 runners each were comparablein age, weight, and body surface area. Cardiovascular risk factorswere assessed by measuring arterial pressure before and duringexercise (150 watts) and determination of plasma lipoproteins,uric acid, glucose and white blood cell count before and aftera marathon run. RESULTS: All measured laboratory values such as high-density lipoproteincholesterol (P<0.05), low-density lipoprotein cholesterol(P <0.05), total cholesterol (non-significant), triglycerides(non-significant), blood sugar (non-significant), uric acid(P <0.05), and white blood cell count (P <0.05) indicateda lower cardiovascular risk in the fastest when compared withthe slowest runners. Resting blood pressure was similar in thethree groups but consistently lower at all levels of exercisein the fittest when compared with the less fit runners. Thefittest runners also showed greater increases in high-densitylipoprotein cholesterol after the marathon run (14% vs 8% inthe slowest runners, P<0.05). CONCLUSIONS: We conclude that even at the extreme end of a continuum suchas represented by well-conditioned, middle-aged marathon runners,cardiovascular risk factors are related to the degree of fitness,as measured by the marathon running time.  相似文献   
94.
Objectives. To examine relationships between body mass index (BMI) and cardiovascular risk factors in 279 Europeans and 231 Polynesian Pacific Islanders in New Zealand.

Methods. Participants were recruited from Seventh‐Day Adventist church meetings or camps, and were surveyed by self‐administered questionnaire. Blood pressure, weight and height were measured. Fasting blood samples were analysed for lipids, glucose and fructosamine.

Results. Age‐adjusted BMI was higher in Pacific Islanders than in Europeans: 32.8(0.3) versus 25.6(0.3); means(SE); p = 0.0001). In Europeans, BMI was positively associated with systolic and diastolic blood pressures, triglycerides, total cholesterol, LDL cholesterol and fasting blood glucose, and negatively associated with HDL cholesterol. In Pacific Islanders, BMI was associated only with systolic and diastolic blood pressures, and with HDL cholesterol. These associations were stronger in Europeans than in Pacific Islanders.

Conclusions. In this group of Pacific Islanders, the association between BMI and cardiovascular risk factors was weaker than in Europeans. This suggests that either BMI is a poor measure of adiposity in Pacific Islanders, or that adiposity may be less strongly linked to cardiovascular disease in Pacific Islanders.  相似文献   

95.
Summary Blood (3.4–13.5% of blood volume) was pumped in and out of the circulation of rats at different rates and period lengths during continuous measurements of blood conductivity (reciprocally related to hematocrit) and arterial pressure. Hct followed the same zig-zag course as the induced changes of blood volume in every case, indicating that fluid shifts (v) between interstitium and intravascular space closely follow blood volume changes. As the het increase during reinfusion was not as great as the preceding decrease, hct dropped continuously during the 20–90 minutes of experimentation, so that a final volume increase (v) by about 4% was calculated, which was confirmed by a corresponding decrease of plasma protein concentration. Both final v and v during periodic volume change (% B.V.) were greater when arterial pressure dropped. v was directly related to % B.V. but not to its rate of change. Heart rate dropped slightly at the end of the reinfusion periods, whereas it rose to control at the end of the withdrawal periods. The results were regarded as evidence of blood volume regulation proportional to the absolute volume of blood lost in non-hypotensive hemorrhage.Supported by DFG-grant AZ 3/3  相似文献   
96.
Summary The uterine inhibitory effect and potential maternal and fetal side effects of two -mimetic compounds, ritodrine hydrochloride and fenoterol hydrobromide, were compared in a randomized trial. The drugs were administered by intravenous infusion to 24 healthy term nulliparous women during effective first-stage labour; each of them received fenoterol (1, 2, or 4 µg/min) or ritodrine (100, 200, or 400 µg/min). There was no difference between the drugs in the intensity of the uterine inhibition. However, for a similar inhibitory effect, the duration of tocolysis was longer after ritodrine. During the intrapartum and neonatal periods, neither compound induced any change in the fetal parameters investigated, and their effects on maternal parameters were comparable.  相似文献   
97.
The recently described "Sunct" syndrome is a rare picture of unilateral, shortlasting headache attacks accompanied by autonomic phenomena (conjunctival injection, tearing, etc.) on the symptomatic side. Heart rate and blood pressure were monitored in two elderly "Sunct" patients during and outside headache attacks. An ultrasound Doppler servo method was used for the non-invasive, continuous, beat-to-beat determination of instantaneous arterial blood pressure. In a third patient, systolic and diastolic blood pressure, both outside and during pain paroxysms, were assessed using the standard Korotkoff method. Heart rate was found to be significantly decreased during pain paroxysms. Systolic blood pressure was observed to be significantly increased during attacks, when compared with the inter-attack period, while a less consistent pattern was observed for diastolic blood pressure. Some of the changes in the cardiovascular system seemed to start prior to pain onset. Therefore, it seems unlikely that these changes were caused by pain activation of the sympathetic nervous system or the oculocardiac reflex.  相似文献   
98.
Symptoms suggestive of dysautonomia are often reported in Myotonic Dystrophy (MD) patients. 12 patients with MD underwent cardiovascular function testing with assay of plasma noradrenaline (NA) and adrenaline (A) in supine rest condition and after orthostatic and cold stimulus. Statistical analysis showed no differences between MD patients and an age and sex matched control group.
Sommario Nei pazienti affetti da Distrofia Miotonica si riscontrano spesso sintomi che suggeriscono un'alterata funzione del Sistema Nervoso Vegetativo. Abbiamo sottoposto a valutazione dei riflessi cardiovascolari e dei livelli ematici di catecolamine (adrenalina e noradrenalina) in condizioni basali, in psizione supina e dopo lo stimolo ortostatico e cold-pressor 12 pazienti affetti da Distrofia Miotonica. L'analisi statistica dei dati non ha mostrato differenze fra i pazienti e un gruppo di controllo comparabile per sesso ed età.
  相似文献   
99.
The purpose of this study was to evaluate the stability of the arterial PCO2 (PaCO2) to end-tidal PCO2 (PETCO2) partial pressure difference (Pa-ETCO2) during surgery using PETCO2 monitoring, in children with congenital heart disease (CHD). Forty children with CHD were studied: ten children with no interchamber communication and normal pulmonary blood flow (PBF) (normal group); ten acyanotic children with increased PBF (acyanotic-shunting group); ten cyanotic children with mixing type lesions and normal or increased PBF (mixing group), and ten cyanotic children with right-to-left intracardiac shunts demonstrating decreased and variable PBF (cyanotic-shunting group). Simultaneous PaCO2 recordings and PETCO2 measurements were obtained for each patient during five intraoperative events: (1) control time, arterial line placement under anaesthesia; (2) time 1, patient preparation; (3) time 2, immediately after sternotomy; (4) time 3, after heparin administration; and (5) time 4, immediately after aortic cannulation. Initially, cyanotic children demonstrated a greater Pa-ETCO2 compared with acyanotic children (P less than 0.05). There was no difference in the Pa-ETCO2 over time in the control, acyanotic-shunting, or mixing groups. The Pa-ETCO2 in the children with cyanotic-shunting lesions at times 2 and 3 was greater (P less than 0.05) than at their control times. We conclude that the Pa-ETCO2 of children with acyanotic-shunting and mixing congenital heart lesions is stable intraoperatively, although patients with mixing congenital heart lesions may demonstrate large individual variations. In children with cyanotic-shunting congenital heart lesions, the Pa-ETCO2 is not stable. The PETCO2 cannot be used during surgery to estimate reliably the PaCO2 in children with cyanotic CHD.  相似文献   
100.
The purpose of this study was to compare propofol-sufentanil with enflurane-sufentanil anaesthesia for patients undergoing elective coronary artery bypass graft (CABG) surgery with respect to changes in (1) haemodynamic variables; (2) myocardial blood flow and metabolism; (3) serum cortisol, triglyceride, lipoprotein concentrations and liver function; and (4) recovery characteristics. Forty-seven patients with preserved ventricular function (ejection fraction greater than 40%, left ventricular end diastolic pressure less than or equal to 16 mmHg) were studied. Patients in Group A (n = 24) received sufentanil 0.2 microgram.kg-1 and propofol 1-2 mg.kg-1 for induction of anaesthesia which was maintained with a variable rate propofol (50-200 micrograms.kg-1.min-1) infusion and supplemental sufentanil (maximum total 5 micrograms.kg-1). Patients in Group B (n = 23) received sufentanil 5 micrograms.kg-1 for induction of anaesthesia which was maintained with enflurane and supplemental sufentanil (maximum total 7 micrograms.kg-1). Haemodynamic and myocardial metabolic profiles were determined at the awake-sedated, post-induction, post-intubation, first skin incision, post-sternotomy, and pre-cardiopulmonary bypass intervals. Induction of anaesthesia produced a larger reduction in systolic blood pressure in Group A (156 +/- 22 to 104 +/- 20 mmHg vs 152 +/- 26 to 124 +/- 24 mmHg; P less than 0.05). No statistical differences were detected at any other time or in any other variable including myocardial lactate production (n = 13 events in each group), time to tracheal extubation and time to discharge from the ICU. We concluded that, apart from hypotension on induction of anaesthesia, propofol-sufentanil anaesthesia produced anaesthetic conditions equivalent to enflurane-sufentanil anaesthesia for CABG surgery.  相似文献   
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