PubMed Health⌕ Search

Biomedical subjects

B Neidhardt

Publications and source records attributed to B Neidhardt.

At least 19 recordsLinked to original sources
PubMed2001

The detrimental role of colloidal volume substitutes in severe ovarian hyperstimulation syndrome: a case report.

Although, the mechanisms for the development of ovarian hyperstimulation syndrome (OHSS) are still not clear, the symptoms usually correlate with the levels of serum estradiol and ovarian enlargement. We report a case, where the clinical course was unusually prolonged. When menstrual bleeding had already occurred, serum estradiol was less than 10 pg/ml and the ovaries were almost normal in size, the patient developed pleural effusion and a significant alteration in blood-coagulation. This was most likely caused by an over-infusion of hydroxyethyl starch (HES) over 10 days. The pleural effusion contained high levels of HES, reaching 74% of the plasma concentration as measured by a novel method after acidic hydrolysis of HES. Carbohydrates as dextran and HES are well known to interact with the blood-coagulation system. Increase capillary permeability, typical of OHSS, leads to loss of colloidal substances into the third space, where HES is slowly degraded and osmotic pressure is high. This might prolong and aggravate the urine of OHSS.

Adult↗
PubMed2001

Cerebral vein thrombosis and prothrombin gene (G20210A) mutation.

Recently, prothrombin gene mutation G20210A has been associated with elevated thrombosis risk and rarely with cerebral vein thrombosis (CVT). Three patients are described who had this genetic predisposition and who developed CVT in an unusual constellation with other factors. In the first patient, the intake of valproic acid (VPA) may have played an aggravating role in the development of CVT; in the second patient diagnosis of coagulation disorder was made during pregnancy consultation 6 years after CVT; in the third patient the CVT occurred at the age of 78 years. In patients with CVT, coagulation-examinations should include tests for the prothrombin gene (G20210A) mutation.

Adult↗
PubMed2000

Plasma levels of eicosanoids after transfusion of intraoperatively salvaged blood.

BACKGROUND: The interest in autologous red blood cell salvage is increasing rapidly, but it is well known that platelets and white cells are activated during cell washing. Therefore, we aimed to determine whether or not eicosanoids transfused together with the salvaged blood are responsible for nonhemolytic immunological transfusion reactions. MATERIALS AND METHODS: In 11 patients who underwent radical prostatectomy we studied the release of eicosanoids, prostaglandin E(2) (PGE(2)) and thromboxane B(2) (TxB(2)), in association with reinfusion of intraoperatively salvaged blood. Blood samples were taken before operation, on days 1 and 3 after operation and before and after cell washing. RESULTS: There was a twofold increase in PGE(2) and a twentyfold increase in TxB(2) in the unwashed salvaged blood. Washing caused a reduction in eicosanoid plasma levels of up to 95%, but a significantly lower level in relation to its corresponding preoperative value was only found for PGE(2). After transfusion of an average of 420 ml RBC sediment from washed blood, the patients' plasma concentrations of PGE(2) and TxB(2) on the 1st and 3rd postoperative day did not significantly differ compared to baseline values. CONCLUSION: Our data support the notion that RBC sediment from 'salvaged' and washed autologous blood contains increased amounts of PGE(2) and TxB(2). It remains, however, questionable if these passively infused eicosanoids become biologically active. According to our study, the PGE(2) and TxB(2) transfused are apparently not responsible for nonhemolytic immunological transfusion reactions.

Aged↗
PubMed1998

A survey of blood utilization in children and adolescents in a German university hospital.

There are no detailed data on blood use with regard to diagnoses of recipients during infancy, childhood and adolescence. Available information on this issue is incomplete and no longer current. We conducted a survey of blood component use in children and adolescents in an acute-care university hospital in the greater area of Nuremberg between June 1994 and September 1996. Packed red blood cells (RBCs), fresh-frozen plasmas (FFPs) and platelet (PLT) components were evaluated for the recipients discharge diagnoses. Source study files were extracted from the hospital transfusion service and the medical records department. Transfused units were listed by broad diagnostic categories and leading diagnostic groups formed from principal diagnoses of the recipients according to the International Classification of Diseases, 9th edn (ICD-9). 34.3% of 2869 RBC cell units, 35.0% of 1095 FFP units and 5.0% of 1028 PLT components were used in patients with congenital diseases, mainly cardiac defects. The disease category neoplastic diseases was next most frequently associated with blood transfusion diagnosed in recipients of 23.9% of all RBCs, 15.6% of all FFP units and in 66.4% of all PLT units. Malignant diseases and benign haematological diseases (diagnostic categories II and IV) accounted for 68.9% of all costs of blood component transfusion. These findings demonstrate the increased importance of platelet transfusion for the organization of local and regional blood donation programmes and for cost analysis exercises. The study shows that detailed information on local blood use may be obtained quickly using available data collections of transfusion services and medical record departments.

Adolescent↗
PubMed1998

Evaluation of a platelet apheresis technique for the preparation of leukocyte-reduced platelet concentrates.

OBJECTIVES: Reduction of the white blood cell (WBC) contamination in platelet concentrates (PC) protects patients from the immunological and infectious side effects of platelet transfusion caused by WBC. This can be done either by filtration of the PC or by improved apheresis techniques that yield WBC-poor preparations. METHODS: To evaluate an improved technique for platelet collection, we carried out 201 separations in 89 healthy cytapheresis donors using the new COBE Spectra leukoreduction system (LRS) and compared the results with those of standard dual-needle separations obtained with the same cell separator. RESULTS: A small but statistically significant difference was found in platelet collection efficiency in comparison with the standard non-LRS software procedures (LRS: 52.6 vs. 56.3% for the reference). However, median WBC contamination was only 0.01 x 10(6) WBC per LRS product. This significant (p < 0.0005) improvement corresponds to a 10-fold reduction of WBC as compared with the standard dual-needle technique. CONCLUSIONS: The COBE Spectra LRS system produced PCs with a platelet collection efficiency nearly equal to previous techniques and with a residual WBC content satisfying even the most stringent criteria for WBC-depleted blood components. As this purity is achieved without important platelet loss, conventional fiber filtration no longer seems necessary in this kind of PC.

Centrifugation↗
PubMed1997

[Advantages and limitations of intraoperative mechanical autotransfusion in al prostatectomies].

UNLABELLED: Intraoperative autotransfusion (MAT), preoperative autologous blood donation, and preoperative normovolaemic haemodilution are three different methods to avoid homologous blood transfusion during surgical procedures. The controversial use of MAT via cell saver in tumour surgery as well as contamination of the operative field with urine illustrate the particular difficulties of autologous blood transfusion in connection with radical prostatectomy. We investigated changes in the osmotic resistance of the retransfused red blood cells (RBC), bacterial contamination, changes in coagulation parameters, and the presence of tumour cells. PATIENTS AND METHODS: After written informed consent, 24 patients who presented for radical prostatectomy were randomly allocated to either a group that used MAT or a group that used homologous transfusion. The patients received "balanced anaesthesia" with midazolam, fentanyl, atracurium, and nitrous oxide/oxygen. The analysed parameters from the preoperative period to the 3rd postoperative day are shown in Table 1. The Haemonetics 3 Plus Cell Saver was used for autotransfusion. RESULTS: Our results showed that the haematologic parameters, coagulation factors, and serum chemistry did not differ between the two groups (Tables 2-4). However, there were significant differences during the investigated period. The osmotic resistance of the salvaged RBCs was higher than that preoperatively. Furthermore, there were no tumour cells in the autologous salvaged RBCs. CONCLUSION: Our results showed no decrease in the quality of the autotransfused RBCs, urine was not retransfused; and there were no significant differences between the groups postoperatively. Although there were no tumour cells in the salvaged blood, the possibility of blood irradiation is discussed. We concluded that because of the risk of infection of homologous blood products, MAT is a safe possibility to reduce the amount of homologous blood transfusion required in connection with radical prostatectomy.

Aged↗
PubMed1996

Stem cell separation in paediatric patients.

We performed 28 separations in 11 children weighing from 14 to 72 kg (median: 27 kg) using either the Cobe Spectra or the Fresenius AS 104 cell separator. For children under 20 kg, human albumin solution was used for the last 200 mL of the priming procedure instead of NaCl. Blood flow was reduced to 30-50 mL min-1 depending on the children's size and weight to prevent citrate reactions. Within 149-337 min we processed three times the patients' total blood volume and collected 309.7 x 10(6) (102.9-1140.0) mononuclear cells (MNC) and 2.01 x 10(6) (1.90-6.50) CD34+ cells per kg body weight. These results were comparable to the results we previously obtained in adults. We conclude from these initial results that peripherae blood stem cells (PBSC) separations, with both devices, can be adapted successfully to the needs of paediatric patients.

Antigens, CD34↗
PubMed1996

Separation of peripheral blood derived stem cells in children.

We performed 28 separations in 10 children from 14 to 44 kg (median: 24 kg) using either the Cobe Spectra or the Fresenius AS 104 cell separator. For children below 20 kg, human albumin solution was used for the last 200 ml of the priming procedure instead of NaCl. Blood flow was reduced to 30 - 50 ml/min depending on the childrens' size and weight to prevent citrate reactions. Within 149 - 337 minutes we processed 3 x the patients' total blood volume and collected 326.9 x 10(6) (76.5-1, 140.0) MNC and 2.03 x 10(6) (0.14-10.12) CD34+ cells per kg body weight. These results were comparable to the results we previously obtained in adults. We conclude from these initial results that PBSC separations with both devices can be adapted successfully to the needs for paediatric patients.

Adolescent↗
PubMed1996

[Expanded serologic infection testing of autologous blood donors: a report of experiences].

PURPOSE: The transmission of hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV-1/2) may cause serious disease in the recipient in cases of inadvertant homologous transfusion of autologous blood. Therefore data on the incidence of these infections in autologous blood donors are necessary. METHODS: We tested 7,438 autologous donations from 3,030 patients for anti-HIV, anti-HCV, and HBsAG. In addition, we tested all patients for antibodies to Treponema pallidum and hepatitis B virus core antigen (anti-HBc) and for elevated serum ALT levels. Confirmation tests were performed only for positive anti-HIV-EIAs. RESULTS: The frequencies of anti-HIV, anti-HCV, and HBsAG were 0.05, 2.8 and 0.6% of all units. The rate of anti-HCV decreased from 4.0 to 3.4% after introduction of a 2nd generation EIA but was only 0.6% using a 3rd generation EIA. Anti-HBc was positive in 9.4%, the TPHA test in 0.5%. ALT was above 45 U/I in 1.2%, but outside the sex related normal range in 8.4% of all units. 23.7% of all donations positive for anti-HIV, anti-HCV, or HBsAG showed at least one pathologic surrogate test; 7.5% of all surrogate marker positive units contained anti-HIV, anti-HCV, or HBsAG. DISCUSSION: The overall frequency of anti-HIV, anti-HCV, and HBsAG was only 3.45% of all autologous donations and was reduced further after introduction of 2nd and 3rd generation anti-HCV-EIAs. However, the rate of surrogate marker positive units was 10.9%. The overlap between both groups was remarkable. We conclude from our data that procedures to minimize the risk of inadvertant homologous transfusion of autologous blood are necessary despite the implementation of screening tests in autologous donation programs.

Adolescent↗
PubMed1994

Are single-needle protocols equivalent to dual-needle protocols for platelet apheresis?

In light of the increasing demands being placed on cytapheresis donors and their occasional venous problems, it has become necessary to use 1-needle in addition to 2-needle separation techniques in thrombocytapheresis. We therefore compared five 1-needle and three 2-needle programs on four different cell separators and found that meanwhile both the platelet yields and the leukopenia (controlled by Nageotte chamber counting) of the products obtained with the 1-needle technique are equivalent to those obtained using the 2-needle technique, as long as the program is suitably adjusted.

Blood Cell Count↗
PubMed1993

von Willebrand factor: an endothelial marker to monitor in-vitro fertilization patients with ovarian hyperstimulation syndrome.

A retrospective study was conducted to evaluate the possible role of endothelial and extracellular factors in the pathophysiology of ovarian hyperstimulation syndrome (OHSS). Plasma changes in von Willebrand-Jürgen factor were correlated with the clinical condition of hyperstimulated patients, since the rise of capillary permeability is the central event in all subsequent morbidity. The corresponding oestradiol levels and ultrasound parameters were assessed. In-vitro fertilization patients designated as 'high responders' and with oestradiol values > 2500 pg/ml and > 8 pre-ovulatory follicles at the time of human chorionic gonadotrophin (HCG) injection were assessed. Among 62 patients, 37 fulfilled these criteria and 18 developed OHSS, indicating the low predictive ability of ultrasound and oestradiol values alone. The remaining 19 patients served as control group. von Willebrand factor-associated antigen in plasma was measured using enzyme-linked immunosorbent assay and ristocetin co-factor activity by an aggregatometric test. Basal values of the two groups of patients did not differ but there were large inter-individual variations. A slight increase occurred in the control group until the day of HCG although individual cycles showed 'no change of pattern' or a 'decreasing tendency' from the start. Some patients allocated to the non-hyperstimulated type showed a steep increase of values followed by a decline. A consistent increase in the OHSS group lasted after embryo transfer even to the late corpus luteum phase. These subtle changes of capillary permeability or damage always preceded the clinical signs, such as ascites, haemoconcentration, hypoproteinaemia and pleural effusion. Mean values differed in the two groups from the day preceding ovum retrieval.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

[Postpartum hemophilia A with factor VIII inhibitor].

An abnormal life-threatening haemorrhagic diathesis occurred 6 weeks after delivery in a 25-year-old female. The reason was a spontaneously acquired factor VIIIC inhibitor haemophilia. The clinical presentation was characterised by extensive deep-seated soft-tissue haemorrhages of the extremities, a retroperitoneal haemorrhage, haematuria and recurrent joint bleedings. The activity of factor VIIIC decreased to below 1% of normal. The factor VIII inhibitor reached a maximum of 122 Bethesda units. The recurrent knee joint haemorrhages responded well to treatment with an activated prothrombin complex concentrate (Feiba). Repeated Feiba administration did not lead to an increase of the factor VIII inhibitor. It disappeared completely within 16 months and did not recur during a second pregnancy. The pregnancy was without complications and delivery on time resulted in a healthy child. Six months after the second pregnancy both mother and child showed no evidence of a disorder of haemostasis.

Adult↗