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[Pre and post-operative autotransfusion. A comparative study of hematology, biochemistry and red cell metabolism in pre-donated blood and blood from post-operative surgical drainage].

PURPOSE: The widespread use of aggressive surgical procedures, along with the increasing incidence of traffic accidents, has raised the necessity of homologous blood beyond the supplies of blood banks. This fact, plus the risks of homologous transfusion and the costs of blood bank maintenance, has prompted the advance of blood saving procedures such as autotransfusion, both in the pre-deposit (preoperative autotransfusion, POA) and the surgical drainage reinfusion (postoperative autotransfusion, SDR) modalities. As there is some controversy about the use of one or the other of the above procedures, the purposes of this study were: 1) to analyse the haematological and biochemical characteristics of blood, both pre-donated and stored at 4 degrees C for 4 weeks, and that recovered from surgical drains, from patients subjected to programmed orthopaedic or heart surgery; 2) to assess the metabolic and functional state of red cells attained from that blood, and 3) to compare the results achieved. MATERIAL AND METHODS: The following data were examined: red cell count, haematocrit, haemoglobin, red cell indicates, white cell count, platelet count, free plasma haemoglobin, red cell morphology, glucose, cholesterol, triglycerides, phospholipids, serum proteins and their fractions, ions, histamine, red cell glucose and amino acid transport, and ATP and 2,3-DPG content. RESULTS: The red cells, haemoglobin and haematocrit concentrations in POA blood did not show significant variations during the storage for 4 weeks and their values were significantly higher than found in drained blood. The biochemical values showed heterogeneous variations. Glucose and amino acid uptake by red cells of POA blood slightly decreased in the first 2 weeks of storage but always less than measured in SDR red cells. In POA blood it was noticed a progressive decrease in intra-erythrocytic ATP and 2,3 DPG, those levels being normal in SDR. DISCUSSION: In spite of lower haematocrit and haemoglobin but higher free plasma haemoglobin content, drained blood had higher ATP and 2,3-DPG concentration than pre-deposit, stored blood. Drained blood showed also less ion alterations and probably a lesser immunosuppressor capability. Thus, postoperative blood recovery seems a good source of red cell, with high oxygen transport power, and so, alone or in combination with pre-donated blood, it may contribute to reduce the necessities for homologous blood and decrease its risks.

2,3-Diphosphoglycerate↗

Variability of indirect methods used to determine blood pressure. Office vs mean 24-hour automated blood pressures.

Blood pressure is a cardiovascular measurement with dynamic characteristics that can be influenced by a number of internal and external factors. The preferred blood pressure determination method would be one that reduces variability between measurements and that reflects the true blood pressure level. In this article, we present the variability of, and agreement between, the blood pressures collected by two indirect methods on the same patients during a hypertensive research project. Data obtained on patients in a typical clinical setting are also provided. Twenty-four-hour diastolic pressures obtained by the automated method demonstrated no regression to a lower mean, while blood pressures obtained casually in the office exhibited such regression. The 95% confidence interval of repeated measures for casual office blood pressure on a patient in a research setting (35/17 mm Hg) or in typical clinic practice (26/19 mm Hg) were similar, while the range of the mean 24-hour automated blood pressure monitoring (21/11 mm Hg) was smaller and demonstrated less variability. The magnitudes of the differences in blood pressures obtained on separate occasions in the same subjects were significantly lower with automated vs casual blood pressure determination methods (7.9/4.6 vs 13.7/7.4 mm Hg for both systolic and diastolic pressures). The agreement (95% confidence interval) between blood pressures obtained by the two methods (19/12 mm Hg) was found to be similar to the repeatability of automated blood pressure monitoring alone, and superior to that for data recorded casually in the office (35/17 mm Hg). Thus, the variability in mean 24-hour automated blood pressures is less than that for casual office blood pressures. The clinician should understand that the variability of blood pressures measured on an individual may be much greater than that reported for populations of hypertensive patients, and must be considered when applying epidemiologic group data to a specific patient. Moreover, any methodology of indirect blood pressure measurement that may reduce the variability and improve repeatability of casual office blood pressures deserves further consideration.

Ambulatory Care↗

Studies of controlled reperfusion after ischemia. XXII. Reperfusate composition: effects of leukocyte depletion of blood and blood cardioplegic reperfusates after acute coronary occlusion.

OBJECTIVES: This study evaluates the role of leukocyte depletion during initial reoxygenation with normal blood and blood cardioplegic reperfusates in limiting reperfusion damage. METHODS: Twenty-eight dogs underwent 2 hours of ligation of the left anterior descending coronary artery. The initial reperfusate (37 degrees C) was delivered on total vented bypass to the left anterior descending artery by a calibrated pump via an internal mammary artery graft at 50 mm Hg for 20 minutes. Eight dogs received normal (normokalemic, nonenriched) blood reperfusion (leukocyte count 8000/mm3) and six were reperfused with leukocyte-depleted normal blood (leukocyte count less than 100/mm3). Of 14 dogs reperfused with substrate-enriched (hyperkalemic) blood cardioplegic solution, six received a cardioplegic solution with a leukocyte count less than 100/mm3. RESULTS: Leukocyte depletion of normal blood reduced reperfusion-induced arrhythmias from 63% to 17% (p less than 0.05). Coronary vascular resistance at initial reperfusion was low and remained low during substrate-enriched blood cardioplegic reperfusion with both normal and reduced leukocyte counts. In contrast, coronary vascular resistance rose 63% with normal blood reperfusion, and this increase was avoided by leukocyte depletion (2.6 versus 4.0 mm Hg x ml/min, p less than 0.05). Coronary vascular resistance after 20 minutes was, however, higher than that with blood cardioplegia with normal or decreased leukocyte counts. Negligible functional recovery followed reperfusion with normal blood and leukocyte-depleted blood (12% and 6% of control systolic shortening). In contrast, substantial segmental recovery followed blood cardioplegic reperfusion (73% systolic shortening, p less than 0.05) but was not improved by leukopheresis (81% systolic shortening). Leukocyte depletion of normal blood reperfusate reduced histochemical damage from 53% to 38% (p less than 0.05), but the least histochemical damage followed blood cardioplegic reperfusion with a normal or reduced leukocyte count (8% or 11%, p less than 0.05). CONCLUSIONS: These findings suggest an important role for leukocytes in reperfusion damage, but reperfusate leukocyte filtration alone is inferior to blood cardioplegic reperfusion. Leukocyte depletion of blood cardioplegic solutions seems unnecessary after only 2 hours of ischemia.

Animals↗

Comparison of the hemostatic effects of fresh whole blood, stored whole blood, and components after open heart surgery in children.

In a double-blind study, we compared the postoperative (post-op) blood loss in 161 children undergoing open heart surgery with cardiopulmonary bypass whose immediate post-op transfusion requirements were met with either very fresh whole blood (VFWB), 24- to 48-hour-old whole blood or reconstituted whole blood (packed red blood cells, fresh frozen plasma [FFP], and platelets). Assignment to treatment groups was not strictly random but dependent, in part, on the ability of families to provide directed donors for fresh blood. The three patient groups were comparable with respect to patient age, pre-op coagulation profiles (bleeding time, prothrombin time, activated partial thromboplastin time, platelet count, fibrin split products, fibrinogen, and platelet aggregation tests) difficulty of operative procedures and time spent on CPB. Mean 24-hour post-op blood loss in milliliters per kilogram was 50.9 +/- 9.3 in the VFWB group, 44.8 +/- 6.0 in the 24- to 48-hour-old group, and 74.2 +/- 8.9 in the reconstituted group (p = .03). When blood loss was compared in the 93 children less than 2 years of age, mean blood loss was 52.3 +/- 10.8 in the VFWB group, 51.7 +/- 7.4 in the 24- to 48-hour-old group, and 96.2 +/- 10.7 in the reconstituted group (P = .001). For subjects who had received reconstituted blood, 30-minute and 3-hour post-op platelet aggregation responses to adenosine diphosphate (10 mumol/L) and 30-minute aggregation response to epinephrine (2.5 mumol/L) were more depressed than in the VFWB and 24- to 48-hour groups (P less than .001, P = .005, and P = .02). Comparison of other post-op coagulation tests could not explain the increased blood loss in the reconstituted group. We conclude that the transfusion of less than 48 hours old whole blood is associated with significantly less post-op blood loss than the transfusion of packed red blood cells, FFP, and platelets in children under 2 years old who underwent complex cardiac surgery. The blood losses associated with the transfusion of VFWB and 24- to 48-hour-old blood are comparable and may be, in part, due to better functioning platelets.

Age Factors↗

Effect of measuring ambulatory blood pressure on sleep and on blood pressure during sleep.

OBJECTIVE: To assess whether recording of ambulatory blood pressure at night causes arousal from sleep and a change in the continuous blood pressure recorded simultaneously. DESIGN: Repeated measurement of blood pressure with two ambulatory blood pressure machines (Oxford Medical ABP and A&D TM2420) during continuous measurement of beat to beat blood pressure and continuous electroencephalography. SETTING: Sleep research laboratory. SUBJECTS: Six normal subjects. MAIN OUTCOME MEASURES: The duration of electroencephalographic arousal and the beat to beat changes in blood pressure produced by the measurement of ambulatory blood pressure; the size of any changes that this arousal and change in blood pressure produced in the blood pressure recorded by the ambulatory machine. RESULTS: Both ambulatory blood pressure machines caused arousal from sleep: the mean duration of arousal was 16 seconds (95% range 0-202) with the ABP and 8 seconds (0-73) with the TM2420. Both also caused a rise in beat to beat blood pressure. During non-rapid eye movement sleep, this rise led to the ABP machine overestimating the true systolic blood pressure during sleep by a mean of 10 (SD 14.8) mm Hg and the TM2420 by a mean of 6.3 (8.2) mm Hg. On average, diastolic pressure was not changed, but measurements in individual subjects changed by up to 23 mm Hg. These changes varied in size among subjects and stages of sleep and were seen after measurements that did not cause any electroencephalographic arousal. CONCLUSIONS: Ambulatory blood pressure machines cause appreciable arousal from sleep and therefore alter the blood pressure that they are trying to record. This effect should be taken into account when recordings of blood pressure at night are interpreted in clinical work and epidemiological research.

Adult↗

Effect of increased whole blood viscosity on regional blood flows in chronically hypoxemic lambs.

In chronic hypoxemia blood flow and oxygen supply to vital organs are maintained, but to nonvital organs they are decreased. We measured organ blood flows (microspheres) and whole blood viscosity in 10 chronically hypoxemic lambs, with an atrial septal defect and pulmonary stenosis, and in 8 control lambs. Vascular hindrance (resistance/viscosity) was calculated to determine to what extent the effect of increased blood viscosity on organ blood flow was compensated for by a decrease in vascular tone. Arterial oxygen saturation was decreased (68 +/- 10 vs. 91 +/- 3%, P < 0.001), and both hemoglobin concentration (145 +/- 10 vs. 109 +/- 9 g/l, P < 0.05) and blood viscosity (4.4 +/- 0.6 vs. 3.6 +/- 0.6 mPa.s, P < 0.05) were increased in hypoxemic lambs. Systemic blood flow, oxygen supply, oxygen uptake, and blood pressures were not significantly different between hypoxemic and control lambs. Myocardial and cerebral blood flow was maintained in hypoxemic lambs, whereas renal, gastrointestinal, splenic, and thyroidal blood flows were at least 30% lower. Vascular hindrance was significantly decreased in the myocardium and tended to be lower in the brain of hypoxemic lambs, but in all other organs it was similar to that in control lambs. It is concluded that blood flow is redistributed in chronic hypoxemia in lambs; myocardial and cerebral blood flow is maintained, whereas blood flow to splanchnic organs, the kidneys, and the thyroids is decreased. The decreased blood flow to organs is a consequence of the increased whole blood viscosity.

Animals↗

[Analysis of the determinant factors for open heart surgery without blood transfusion by the quantification theory--possibility of application of maximum surgical blood order schedule for open heart surgery].

In order to complete operations without blood transfusion we have chosen means of preoperative autologous blood saving and intraoperative autotransfusion, but we have not always achieved our purpose. We examined 29 patients (13 patients without blood transfusion and 16 with blood transfusion) to analyze the determinant factors as to whether open heart surgery without blood transfusion may be indicated or not, according to the quantification theory (type II) and to examine the possibility to apply the maximum surgical blood order schedule (MSBOS) for the open heart surgery by the quantification theory (type I). The analysis of determinant factors revealed hematocrit (Ht) value before saving of blood (more than 40%) as the best contributor of possibility of non-blood transfusion surgery, followed by the amount of blood loss during operation (less than 600 ml), the amount of saving blood (more than 800 ml), body weight (less than 70 kg), calculated Ht value on the beginning of cardiopulmonary bypass (CPB) (more than 24%), CPB time (less than 120 minutes) and the amount of postoperative blood loss (less than 600 ml). The prospective using blood volume at the operation was precisely calculated by the values of 4 preoperative factors, that is, the amount of saving blood, calculated Ht value on the beginning of CPB, CPB time and body weight. Therefore it is important to increase the amount of preoperative saving blood and decrease the amount of surgical bleeding in order to perform operations without blood transfusion, and is possible to apply the MSBOS for the open heart surgery.

Adolescent↗

Reactivity of blood pressure to mental arithmetic stress test, stress-test recovery time, and ambulatory blood pressure in hypertensive and normotensive subjects.

BACKGROUND: Laboratory mental stress testing and 24 h ambulatory blood pressure monitoring may analyse reactivity of blood pressure during provoked stress and stressful situations in daily-life, respectively. OBJECTIVE: To evaluate whether the responses to a mental stress test and during the stress-test recovery time were associated with ambulatory blood pressure parameters. METHODS: Fifty-two untreated male subjects (22 normotensives and 30 hypertensives) were subjected both to mental arithmetic stress testing and ambulatory blood pressure monitoring. RESULTS: We found a positive correlation between baseline and peak-test blood pressures during the stress test and 24 h blood pressures. Maximal values of systolic and diastolic blood pressures measured during the 24 h were also correlated to the maximal systolic and diastolic blood pressures reached during the stress test ( P < 0.001). We observed no relationship between reactivity during the stress test and 24 h parameters. On the contrary, changes in diastolic blood pressure during the time of recovery from the stress test (expressed as percentage-change scores) were correlated to the 24 h diastolic blood pressure parameters, the diastolic load being the most closely associated variable. CONCLUSION: The absence of relationships between variations in blood pressure during the provoked stress and ambulatory monitoring parameters indicates that reactivity of blood pressure to an acute stress does not predict the 24 h profile. However, the correlation between the maximal blood pressure measured by ambulatory monitoring and that observed during stress testing indicates that the maximal 24 h values may show the extreme blood pressure response (like the one provoked acutely by a laboratory stress test) of an individual subject. The correlation between the percentage-change score during the recovery time of diastolic blood pressure and the 24 h diastolic load could account forr a lower than normal capacity for recovery of subjects with persistently high blood pressures.

Journal Article↗

Utilization and efficacy of autologous blood predeposit in radical prostatectomy with lymphadenectomy: implications for blood conservation and physician education programs.

Autologous blood predeposit is a widely used transfusion practice that has become a standard of care for elective surgery. Despite the support for this practice there are unanswered questions in the usage and efficacy of autologous blood programs. This study is a prospective analysis of 52 consecutively audited urologic patients undergoing elective, radical prostatectomy with lymphadenectomy in which all 52 patients predonated autologous blood. Preoperative blood donation, blood transfused, surgical blood lost, and the "transfusion trigger" were evaluated for each of these patients. We conclude (1) the rate of homologous blood exposure (15%) despite preoperative autologous blood donation in every patient indicates a need for innovative blood conservation strategies to minimize homologous blood transfusion in this surgical group. (2) Unnecessary autologous transfusions could be identified in 8 (15%) of 52 patients, all of which were single unit autologous blood transfusions. (3) Physician education programs that emphasize increased procurement of autologous blood along with more conservative transfusion of this blood are needed to avoid necessary homologous blood and unnecessary autologous blood transfusion.

Blood Preservation↗

Blood pressure response to stress tests does not reflect blood pressure variability and degree of cardiovascular involvement in young hypertensives.

The aim of the study was to assess the clinical value of blood pressure response to stress tests and to study its relationship with ambulatory blood pressure monitoring, daily blood pressure variability and hypertensive complications. Cold pressor test for 2 min, hand grip test at 25% of maximal voluntary contraction for 5 min and orthostatism were performed in 223 young men found hypertensive (BP systolic > 140 mmHg and/or diastolic > 90 mmHg) at the military service recruitment check-up. On the basis of ECG and fundoscopic examination, each patient was attributed a score of target organ damage. All patients underwent non-invasive 24-h blood pressure monitoring and 169 patients underwent echocardiographic examination. Hypertension was confirmed in 54.2% of the subjects at ambulatory monitoring. No correlation was found between blood pressure response to stress tests and ambulatory blood pressure, daily blood pressure variability, target organ damage and left ventricular mass. Night-time ambulatory blood pressure were correlated with posterior wall thickness/ventricular diastolic internal diameter ratio (r = 0.26, P < 0.001). A negative correlation was found between the office-daytime blood pressure difference and systolic and diastolic response to orthostatic test (r = -0.309, P < 0.0001 for systolic blood pressure and r = -0.433, P < 0.0001 for diastolic blood pressure) and between supine office blood pressure and blood pressure response to orthostatism (r = -0.186. P = 0.013 for systolic blood pressure and r = -0.442, P < 0.0001 for diastolic blood pressure).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

AGT and RH blood group polymorphisms affect blood pressure and lipids in Afro-Caribbeans.

Population blood pressure variation is most likely due to multiple genes. This is likely the reason why monogenic testing with the angiotensinogen (AGT) gene polymorphisms on chromosome 1 (1q42-43), especially M235T, has met with negative results, especially in those of African descent. The RH blood group system, also on chromosome 1 (1 p36.2-34), has likewise been associated with blood pressure variation in African-Americans and with the rise in blood pressure with age in whites. Using a random sample of the population, we investigated the combined effects of single and combined variation of the AGTN M235T and RH genotypes on blood pressure, lipids, and lipoprotein concentrations in Afro-Caribbeans aged 18-60 years from the island nation of Dominica. In monogenic analysis, AGT M235T was not associated with blood pressure. However, it was associated with HDL (MM 42+/-23, MT 44+/-12, TT 52+/-14 (P=0.002)). RH genotype was significantly associated with systolic blood pressure (P=0.006) and Apo-A (P=0.003). These effects remained after adjustment for age, gender, weight, and BMI. In the polygenetic analysis, AGT M235T and RH were significantly associated with systolic blood pressure (P=0.037; interaction effects, P=0.068). The association of the AGT M235T with blood pressure across RH blood group haplotypes was then tested. Of the five RH haplotypes available for analysis, the AGT M235T was significantly associated with blood pressure within the "D" haplotype (P=0.01). The RH blood group and gender were significantly associated with systolic blood pressure and Apo-A levels (P=0.005 and 0.012, respectively). All interactions were independent of age and weight. In conclusion, we demonstrate a significant association of AGT M235T with blood pressure and cholesterol metabolism in an Afro-Caribbean population in the "genetic context" of the RH blood group system. Further investigation of these interactions may help understand the effects of genetic factors on cardiovascular risk in African-derived and other populations.

Adult↗

Effect of local cold provocation on systolic blood pressure and skin blood flow in the finger.

Demonstration of increased vascular cold reactivity in patients with Raynaud's syndrome is difficult. For medico-legal reasons, it is important to get objective measures of vasospasm in these patients. Evaluation of the degree of vasospasm also provides prognostic information which is useful for patient management. In this study, we compare two methods of arterial circulation measurement. The laser Doppler scanning is a new method, which uses the recently developed laser Doppler perfusion imaging (LDPI) instrument. The aim of the present study was to compare the effect on finger skin blood flow measured with LDPI with changes in finger systolic blood pressure during local cold provocation. The effect of such provocation, skin blood flow and systolic blood pressure, were studied in 15 healthy controls. Six patients with known traumatic vasospastic disease (TVD) were also tested with both methods. Finger skin blood flow was measured with LDPI on the distal phalanx of the index finger of the left hand, every minutes during 6 min of local heating at 40 degrees C followed by local cooling for 3 min at 15 degrees C and then for 3 min at 10 degrees C. Finger systolic blood pressure was measured with strain-gauge method before and after local cooling to 10 degrees C with a cuff perfused with water of desired temperature. The test was performed in the same finger within a week of the laser Doppler scanning. Local finger cooling to 15 degrees C and 10 degrees C caused a significant decrease in blood flow, most marked at 10 degrees C. There was, however, no correlation between the decrease in blood flow and blood pressure. In the TVD-patients decreases in skin blood flow were similar compared with the healthy controls. In contrast, the changes in systolic blood pressure, were outside normal range (systolic quotient <0.65) in five of the six patients (83%), and also in 11 of the 15 healthy controls (73%). In conclusion, there is no correlation between the decrease in finger skin blood flow and systolic blood pressure during local cold provocation. For diagnosis of traumatic vasospastic disease (TVD), local cold-induced changes in finger systolic blood pressure seems superior to changes in skin blood flow, but the ideal clinical method for demonstrating increased cold-induced vasospasm is, however, still lacking.

Adult↗

Effect of heparin on whole blood activated partial thromboplastin time using a portable, whole blood coagulation monitor.

OBJECTIVES: To evaluate the responsiveness of whole blood activated partial thromboplastin time (aPTT) to varying heparin doses in vitro and to examine the ex vivo relationship of whole blood aPTT to plasma heparin concentration. DESIGN: Prospective, controlled laboratory study. SETTING: Surgical suites and laboratory at a tertiary center. PATIENTS: Surgical patients and volunteers at a tertiary center were eligible for inclusion in this study. In vitro evaluation was performed using specimens obtained from each of five, healthy volunteers. Ex vivo evaluation was performed using specimens obtained from 30 cardiac surgical patients before and after systemic administration of heparin for extracorporeal circulation. INTERVENTIONS: Blood specimens were obtained from volunteers and added to syringes containing varying amounts of unfractionated porcine heparin for in vitro evaluation. For ex vivo evaluation, blood specimens were obtained from patients before and after systemic administration of 20 U/kg of heparin. MEASUREMENTS AND MAIN RESULTS: For the in vitro evaluation, specimens were divided into two aliquots after mixing with varying amounts of unfractionated porcine heparin. One aliquot was used to measure whole blood aPTT using a whole blood coagulation monitor immediately after blood collection and 3 mins later, and a second aliquot was used to determine plasma aPTT with a conventional, laboratory-based assay. Linear regression analysis demonstrated a high correlation (r = .94; r2 = .88) between aPTT assay systems and bias analysis demonstrated a mean aPTT measurement difference of 1.6 secs with +/- 2 SD limits of -15 to +18.2 secs. As indicated by comparable regression slopes, the in vitro aPTT responsiveness to increasing heparin concentration was similar with the two assay systems among individual subjects. Whole blood aPTT measurements after 3 mins of blood specimen storage were similar to immediate measurements. For ex vivo evaluation, blood specimens obtained from patients before and after systemic administration of heparin were divided into two aliquots. One aliquot was used to measure whole blood aPTT in duplicate and a second aliquot was used to measure plasma heparin concentration with an antifactor X active chromogenic assay. A high correlation (r = .89; r2 = .79) between whole blood aPTT and plasma heparin concentration was observed. CONCLUSIONS: Heparin responsiveness of whole blood aPTT, measured with a portable whole blood coagulation monitor, is similar to that of conventional laboratory aPTT over a clinically relevant range of heparin concentrations in vitro and ex vivo. On-site whole blood aPTT measurements should be useful in clinical situations requiring rapid aPTT results.

Blood Coagulation↗

The correlation of skin blood flow with age, total cholesterol, hematocrit, blood pressure, and hemoglobin.

Normal skin blood flow at the deltoid region in 55 men whose ages ranged from 20 to 72 years was measured by the xenon-133 clearance method. In addition, the correlation of skin blood flow with age, systolic blood pressure, total cholesterol, hematocrit, hemoglobin, and total protein was analyzed by multiple regression analysis. The following results were obtained. Normal skin blood flow was found to decrease with increase in age, total cholesterol, and systolic blood pressure and showed a tendency to increase with elevation in hematocrit and hemoglobin values. Of the six parameters examined in the present study, the parameter that showed the strongest correlation with skin blood flow at the deltoid region was age, followed in decreasing order by total cholesterol, hematocrit, systolic blood pressure, and hemoglobin. It could therefore be concluded that age is the most reliable factor in clinically estimating skin blood flow. Furthermore, inasmuch as total cholesterol, hematocrit, systolic blood pressure and hemoglobin values also were correlated with skin blood flow, these values also should be taken in account in the synthetic evaluation of skin blood flow. It was skin blood flow at the deltoid region that was strongly correlated with age. This was followed by systolic blood pressure, hematocrit, and hemoglobin. Total cholesterol showed a weak correlation with age, but total protein did not demonstrate any correlation with skin blood flow and age. The results of the present study show that skin blood flow would be poor in the elderly and in patients with arteriosclerosis, hypertension, and anemia. Since it is suggested that the wound-healing process is delayed in such patients, utmost care should be exercised in treating their wounds.

Adult↗

Blood pressure reactions to acute psychological stress and future blood pressure status: a 10-year follow-up of men in the Whitehall II study.

OBJECTIVE: The aim of this study was to examine whether blood pressure reactions to mental stress predicted future blood pressure and hypertension. METHODS: Blood pressure was recorded at an initial medical screening examination after which blood pressure reactions to a mental stress task were determined. A follow-up screening assessment of blood pressure and antihypertensive medication status was undertaken 10 years later. Data were available for 796 male public servants, between 35 and 55 years of age upon entry to the study. RESULTS: Systolic blood pressure reactions to mental stress were positively correlated with follow-up screening systolic blood pressure and to a lesser extent, follow-up diastolic pressure. In multivariate tests, by far the strongest predictors of follow-up blood pressures were initial screening blood pressures. In the case of follow-up systolic blood pressure, systolic reactions to stress emerged as an additional predictor of follow-up systolic blood pressure. With regard to follow-up diastolic blood pressure, reactivity did not enter the analogous equations. The same outcomes emerged when the analyses were adjusted for medication status. When hypertension at 10-year follow-up was the focus, both systolic and diastolic reactions to stress were predictive. However, with correction for age and initial screening blood pressure, these associations were no longer statistically significant. CONCLUSIONS: The results of this study provide modest support for the hypothesis that heightened blood pressure reactions to mental stress contribute to the development of high blood pressure. At the same time, they question the clinical utility of stress testing as a prognostic device.

Acute Disease↗

Measurements of blood pressure with various techniques in daily practice: uncertainty in diagnosing office hypertension with short-term in-hospital registration of blood pressure.

OBJECTIVE: To predict blood pressure outside the clinic from a short-term in-hospital registration for patients referred for ambulatory blood pressure monitoring (ABPM) with special attention to office hypertension. PATIENTS AND METHODS: A series of measurements of blood pressure was performed by the same technician for 187 patients, 82% of whom were being administered antihypertensive therapy. She performed three mercury measurements of blood pressure (Hg stress 1) and then three manually started measurements with a semi-automatic device (Dinamap 1846SX; Dinamap stress) alternated with three manually started readings with a SpaceLabs 90207 monitor (SpaceLabs stress) on the contralateral non-dominant arm. The in-hospital session was continued with 15 automatic Dinamap registrations at 2 min intervals without the technician being present (Dinamap unstressed, five periods of three measurements averaged) before the patient left the hospital for 24h ABPM. RESULTS: The percentages of patients with hypertension in the office (systolic blood pressure >/= 140 mmHg or diastolic blood pressure >/= 90 mmHg, or both) were 80% with Hg stress 1, 76% with Dinamap stress and 85.0% with SpaceLabs stress. Average diastolic SpaceLabs stress was 6.0+/-5.6 mmHg (significantly) higher than diastolic Dinamap stress, whereas the difference between systolic blood pressures was 0.2+/-10.0 mmHg. No further change in blood pressure occurred after the fourth period of Dinamap unstressed measurements. Office hypertension defined as SpaceLabs stress systolic blood pressure >/= 140 mmHg or diastolic blood pressure >/= 90 mmHg, or both, and SpaceLabs daytime systolic blood pressure < 135 mmHg and diastolic blood pressure < 85 mmHg was found in 21 individuals. Office hypertension defined with similar cut-off points in the comparison of Dinamap stress versus Dinamap unstressed period 5 was found in 29 cases, 10 of which overlapped with the definition SpaceLabs stress versus SpaceLabs daytime. The differences between Dinamap stress and Dinamap unstressed period 5 were significantly correlated to the changes of SpaceLabs stress and SpaceLabs daytime both for systolic (r =0.41) and for diastolic (r =0.32) blood pressures. CONCLUSIONS: Measurements of blood pressure in the office with various techniques (mercury, Dinamap and SpaceLabs) are not equivalent. Office hypertension cannot be reliably predicted from a short-term semi-automatic in-hospital registration of blood pressure with a Dinamap device.

Adolescent↗

Anaemia and iron status among blood donors in a blood transfusion unit in Malaysia.

Iron deficiency is a major complication of regular blood donation as a result of regular iron loss from each donated blood unit. Ninety-two regular blood donors and 95 first time blood donors attending a hospital-based blood transfusion centre were assessed as to their haematological and iron status by blood counts and serum ferritin levels as an indicator of iron stores. All donors had passed the haemoglobin-screening test using a copper sulphate method prior to blood donation. Ferritin levels were found to be significantly lower among regular blood donors (47.8 mmol/L) as compared to first time blood donors (94.2 mmol/L). Iron deficiency as observed by low ferritin levels was seen in 7.4% of all first time donors as compared to 17.4% in regular donors. Male first time donors showed a low prevalence of iron deficiency but the prevalence significantly increased with regular blood donation. Female first time and regular blood donors however did not show any significant differences in prevalence of iron deficiency, with both groups exhibiting prevalence rates similar to male regular donors. The association between haemoglobin levels and iron deficiency was poor and the copper sulphate-screening test was found insensitive to anaemia with many donors passing the test and donating blood despite being anaemic. It is concluded that a high prevalence of iron deficiency is present among regular male blood donors and all female donors. Besides, the use of the copper sulphate screening test as a sole criterion for anaemia screening should be reviewed. Ferritin measurements should be included in the routine assessment of blood donors especially among regular blood donors.

Adult↗

Harvesting, characterization, and culture of CD34+ cells from human bone marrow, peripheral blood, and cord blood.

Stem and progenitor cells from a variety of sources including bone marrow, cord blood, and peripheral blood have been used for transplantation. This study compares CD34 cells from all three sources. Flow cytometry analysis of CD34 cells in multiple samples of normal peripheral blood and patient peripheral blood mobilized with chemotherapy (cyclophosphamide/VP16), chemotherapy plus granulocyte colony stimulating factor (G-CSF), and G-CSF alone were compared to bone marrow and cord blood. Although the relative distribution of CD34 percentages in each preparation of cells varied widely, on average the percentage of CD34 cells in these different preparations was 0.15%, 0.6%, 2%, 0.45%, 1.68%, and 0.83% respectively. CD34 subset analysis was performed on these cell preparations using multicolor flow cytometry and antibodies to CD33, CD13, CD45RA, CD19, CD71, and CD38. The major differences observed were that bone marrow CD34 cells contain high percentages of CD19+ cells not found in significant quantity in the other cell preparations and cord blood CD34 cells contained a higher percentage of CD38-cells than the other cell preparations. A magnetic bead system was used with anti-CD34 antibody to purify CD34 cells from mobilized peripheral blood apheresis products, cord blood, and bone marrow. Efficient selection with high purities of CD34 cells was achieved with each of the cell preparations. Comparison of colony-forming activity of each of the cell preparations showed cord blood and mobilized peripheral blood to have slightly higher cloning efficiencies than bone marrow with higher numbers of erythroid blast-forming units (BFU-E) also observed in cord blood CD34 cells. Culture of isolated CD34 cells in liquid culture with interleukin-3, stem cell factor, G-CSF, and granulocyte-macrophage GM-CSF showed over a 100-fold expansion in cell numbers after 25 days, with the peak expansion of colony-forming cells occurring between days 11 and 16. Analysis of day-10 cells from these cultures showed them to be predominantly promyelocytes, myelocytes, and metamyelocytes, with cord blood CD34 cultures showing more promyelocytes than peripheral blood or bone marrow and bone marrow showing more metamyelocytes. Comparison of the proliferation of CD34 cells from these different cell preparations showed that cord blood CD34 cells cultured for 10 days averaged an 85-fold increase in cell numbers followed by mobilized peripheral blood CD34 cells, with an average 56-fold increase, and bone marrow CD34 cells, with an average 49-fold increase.

Adult↗