Biomedical subjects

W Schleinzer

Publications and source records attributed to W Schleinzer.

26 records · Page 2Linked to original sources

PubMed1993

[Autologous blood donation from the viewpoint of the anesthetist].

The anesthesiological aspect regarding autologous donation/autologous predeposition aims at the following criteria: (1) Which patient is eligible for autologous donation? (2) Which kind of monitoring should be established for the donation procedure? (3) What are the quality criteria the autologous predeposit has to meet? (4) What are the logistical aspects of an autologous predeposit program managed by an anesthesis? Under anesthesiological aspects all patients who have been declared eligible for elective surgery should be able to donate an autologous predeposit. Attention should be paid both to an adequate volume substitution, especially in patients with cardiovascular and/or coronary diseases, and to an adequate monitoring during autologous blood donation; e.g., a 3-lead ECG to monitor of cardiac rhythm and heart rate as well as close and discontinuous blood pressure control appear to be appropriate. There is no doubt that the quality criteria an autologous predeposit should meet are the same as those outlined for a homologous product; especially proof of no bacterial contamination is mandatory. Undoubtedly, an anesthesist managing an autologous predeposit program should have a broad experience in and a good knowledge of transfusion medicine.

Anesthesiology↗

PubMed1993

[Monitoring in hemodilution].

Normovolaemic haemodilution is an established part within the 'Concept of Autologous Transfusion'. According to the mechanisms to compensate for the dilution-induced anaemia, monitoring of haemodilution has to consider (1) maintenance of normovolaemia; (2) stability of the cardio-vascular system and of a normal pulmonary function; (3) an adequate myocardial oxygen supply. (1) Normovolaemia: Under routine clinical conditions normovolaemia is controlled by close monitoring of fluid balance (considering surgical blood loss, diuresis, and insensible perspiration). If the expected blood loss is > 2.0 litres, additional monitoring of the central venous pressure appears to be reasonable. It is not a single value of the central venous pressure (CVP) but rather its time-course that allows conclusions on changes of intravascular volume. (2) Cardio-vascular and pulmonary function: Pulmonary function is easily controlled by intermittent arterial blood gas analysis. Non-invasive and discontinuous or invasive and continuous blood pressure recording, respectively, are routinely used for monitoring of cardiovascular function. Heart rate together with the time-course of the CVP give additional information on the cardio-vascular system. Central-venous oxygen saturation is only a minor substitute for mixed venous oxygen saturation; however, its changes with time make it possible to draw conclusions on global haemodynamics and total body oxygen supply. However, in situations of extreme haemodilution--as in Jehova's witnesses--a pulmonary artery catheter has to be used for monitoring the cardio-vascular system as well as bulk oxygen parameters. (3) Myocardial oxygen supply: Monitoring for myocardial ischaemia is routinely performed by ECG. It is both the number and the kinds of leads chosen that give adequate information.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Loss, Surgical↗

PubMed1991

[The "concept of autologous transfusion"].

This study analyzes the need for homologous blood in a prospectively studied group of 4,357 orthopedic-surgical patients after having established the 'Concept of Autologous Transfusion' (CAT) in 1989, in comparison to a retrospectively studied group of 7,485 orthopedic-surgical patients that had been treated exclusively with homologous blood (in 1986 and 1987). Despite an increase by 18% of the number of operations performed (in 1986: 3,698 operations vs. 4,357 operations in 1989), the need for homologous blood has been reduced by more than 80% (in 1986: 12,600 units of homologous packed red blood cells vs. 1989: 2,145 units of homologous blood). This effect has been achieved by the combination of various blood-saving techniques, namely by normovolemic hemodilution in 3,591 patients (82.4%), intra- and post-operative blood salvage in 1,936 patients (44.4%) as well as by 2,261 preoperative autologous blood donations, and by 5,279 preoperative plasmaphereses. Preoperative autologous donations have been accompanied by side effects in 1.3% (mild and moderate); no serious or even fetal complications occurred and all ambulatory patients coming to the hospital just for an autologous donation left for home on the same day.

Blood Component Transfusion↗

PubMed1991

[The safety of preoperative mechanical autologous plasma donation].

Preoperatively performed plasmaphereses in elective surgery enables the patients not only to have an autologous product retransfused but also to receive a product that contains proteins, coagulation factors and immunoglobulins, both in physiological concentration and composition. Moreover, it is a very effective volume substitute, especially in cases in which a great intraoperative blood loss and/or an intense hemodilution may have caused disorders of the coagulatory system due to loss of coagulation factors as well as due to their dilution. Despite the fact that in our study (7540 preoperative autologous plasmaphereses in 4157 patients in 1989) approximately one-third of the patients was older than 70 years and more than 50% had to be put into group IV of the extended/modified ASA-Score, the rate of side effects accompanying autologous plasmapheresis is only 1.3%. No serious or even fatal complications occurred, and all the day-case-patients coming to the hospital just for autologous donations left for home on the same day. Our results demonstrate that a preoperatively performed autologous donation is not only a very effective, but also a very safe method to reduce the need for homologous blood products. If, in elective surgery, a preoperative autologous donation is considered necessary due to the expected blood loss, the general rule for autologous donation is: A patient who is not fit for autologous donation is not fit for elective surgery, either.

Aged↗

PubMed1990

[4 years experience with the Ulm autologous transfusion concept].

After a 4-year period in clinical practice the autologous transfusion concept Ulm (ATU) has proved its value. The effort and expense involved are entirely justified by obvious medical advantages. The patients' active involvement in the therapeutic procedure is a remarkable aspect of positive motivation. Furthermore, the medical staff is positively motivated, too, in spite of the obvious additional load to their daily routine work.

Blood Transfusion, Autologous↗

PubMed1988

[Hemodynamics in donor plasmapheresis].

Several studies have demonstrated that preoperative withdrawal and storage of autologous plasma as fresh frozen plasma is effective in blood conservation. For that purpose patients with elective surgery (orthopaedic surgery, open heart surgery, neurosurgery and others) have to undergo donor plasmapheresis without staying in the hospital. Depending upon the need the procedure can be performed several times preoperatively, taking about 900 ml in a normal weighting subject at once. The collection of autologous plasma should be finished at least 14 days before surgery. In order to investigate the haemodynamic effects of donor plasmapheresis 30 patients scheduled for coronary bypass surgery were devided into two groups. 15 patients underwent plasmapheresis (10 ml plasma/kgbw) by one-needle-technique using a Haemonetics seperator (PCS) after premedication but before onset of anaesthesia. Blood withdrawal was performed with 0.5 ml/kgbw x min. Another 15 patients, serving as control had no plasma withdrawal and were measured at identical times as the other group. Both groups had an identical fluid replacement with 500 ml Ringer's solution during the investigation period. Plasma withdrawn was not substituted by colloidal solution (simulating the situation when plasmapheresis is performed at the outpatient). Haemodynamic measurements (both groups) included heart rate, arterial blood pressure, right- and left-atrial pressure, systemic- and pulmonary-vascular resistance and cardiac output. There were no relevant effects of plasmapheresis on haemodynamic function during and after the investigation period in that patients: neither heart rate, blood pressure or vascular resistance changed significantly nor did pre- and afterload or cardiac index. No differences to the group without plasmapheresis could be observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Transfusion, Autologous↗

PubMed1988

[Preoperative plasmapheresis].

Plasmapheresis is performed during the preoperative patient preparation phase of the Ulm Autologous Transfusion Concept (ATU). On an outpatient basis, weeks or months before the operation, 900 ml autologous plasma is donated per visit using the one needle technique, shock frozen, and stored at -30 degrees C or lower. During a period of approximately 1 1/4 years, 813 patients were studied in order to obtain information (in addition to the observation of the usual vital statistics) concerning the effect of plasmapheresis on homeostasis and coagulation factors directly before, directly after, 2 h after, and 24 h after (in-patients only). A complete electrolyte solution of the Ringer-lactate type was used as volume substitution (1000 ml or 1500 ml). Arterial blood pressure and heart rate showed no significant change. The transient decrease in various laboratory parameters was within tolerable limits. The parameters for blood protein, anti-thrombin III, and immunoglobulin G had already normalized within 24 h. Our more than three year experience with more than 2600 patients and the collective data indicate no reason not to perform plasmapheresis on non-fasting outpatient patients. The for the most part postoperatively transfused autologous fresh frozen plasma represents an ideal, long acting volume substitution which contains such blood components as antithrombin III, immunoglobulins, and factor XIII. These blood components could be a contributing factor for a decreased danger of thrombosis, embolie, and infection, as well as provide for better wound healing.

Blood Coagulation Tests↗

PubMed1980

[Prospective studies on the pathologic mechanism of post-spinal headache in a select group of patients (author's transl)].

In this prospective study 613 patients on whom a total of 783 spinal anaesthetics had been performed, all for urological operations, were questioned and examined. Subjective complaints occured in 102 cases (13%) and were found to be more frequent amongst the female patients. 23 cases (2.9%) developed a typical post-spinal headache, this being more likely to occur if the patient was a woman, was young, and if a 22-Gauge needle was used. The headache usually began on getting up on the day of operation or the first post-operative day, and rarely lasted longer than four days. The pathophysiological changes indicate that the headache is caused by a fall in CSF pressure. The therapy and various methods of preventing this complication are discussed, and the other potential neurological symptoms and signs mentioned.

Adult↗