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Biomedical subjects

L E Pivacek

Publications and source records attributed to L E Pivacek.

At least 37 records · Page 2Linked to original sources
PubMed1993

Infusion of stroma-free cross-linked hemoglobin during acute gram-negative bacteremia.

Twelve dogs were divided into two groups of six each, and were infused with bis-3,5-dibromosalicyl fumarate stroma-free hemoglobin (DBBF-Hb) or albumin. Their responses to an intravenous bolus of Escherichia coli were followed for 4 hr. Bacterial clearance from the blood stream was studied using standard colony counting methodology as well as blood counts, blood chemistries, and clotting factor analysis. There was a significant difference in mean arterial pressure (MAP) over time between DBBF-Hb-treated dogs and those treated with albumin (P < 0.02). While the DBBF-treated dogs had a higher MAP during the 10 min of bacteremia, after 1 hr, there were no longer any appreciable differences between septic dogs treated with DBBF-Hb vs. albumin. Consumption of clotting and natural anticoagulant factors was observed to be similar in both groups, as were endotoxin levels. Blood urea nitrogen (BUN) increased slightly in both groups, while white blood cell counts and clotting factor levels fell in both groups in a similar fashion. There was a more pronounced fall (P < 0.04) in platelet counts in the animals treated with DBBF-Hb. In the dogs treated with DBBF-Hb, there was also a late rise in pCO2 (P < 0.01), a more pronounced fall in pO2, and greater acidosis, which suggested that ventilation perfusion abnormalities may have been exacerbated by DBBF-Hb treatment. Since the exacerbation of respiratory abnormalities was not related to diminished bacterial or endotoxin clearance, the possibility is raised that DBBF-Hb interferes with compensatory respiratory changes during sepsis.

Acute Disease↗
PubMed1992

Intravascular circulation and distribution of human 51Cr-DBBF stroma-free hemoglobin.

Male B6C3HF1 mice were infused with 51Cr-labeled DBBF (bis 3,5-dibromosalicyl fumarate) crosslinked stroma-free hemoglobin (SFH). The intravascular halftime (T50) of the DBBF-SFH, determined from plasma hemoglobin levels, was 0.5 hours in the first 10 minutes and 4.3 hours during the next 50 minutes. At 24 hours, less than 5% of the DBBF-SFH remained. Elution of 51Cr was reflected in a lower T50 determined from the radioactivity levels: during the first 10 minutes the T50 was 0.3 hours; in the next 50 minutes it was 1 hour. The radioactivity sequestered in each organ in the first hour following DBBF-SFH infusion was as follows: 11.2% of the infused radioactivity was in the skin, 11.4% in muscle, 9.1% in the skeleton, and 5% in the liver. After 24 hours, the percentages in skin, muscle, skeleton and liver were 15.4, 10.3, 16.6 and 6.7% respectively. The percentage of infused radioactivity in the gastrointestinal tract and kidney at 1 hour and 24 hours ranged from 3.5 to 5.5%. Less than 0.4% was found in the spleen and lung. At 24 hours, 25% of the radioactivity was recovered in urine and 3% in feces.

Animals↗
PubMed1992

Poor predictive value of hematocrit and hemodynamic parameters for erythrocyte deficits after extensive elective vascular operations.

Fluid resuscitation and transfusion therapy are particularly critical in patients undergoing extensive vascular operations because of diffuse atherosclerosis and the risk of perioperative myocardial infarction. Sophisticated perioperative monitoring has reduced the mortality rate substantially, but indications for transfusion remain controversial. We determined erythrocyte volume, (EV), total blood volume (TBV) and plasma volume (PV) preoperatively and 18 to 24 hours postoperatively in 41 elderly patients (68.8 +/- 1.3 years) undergoing elective vascular operations (30 abdominal aortic aneurysmorrhaphy, ten aortofemoral bypass and one carotid endarterectomy). EV was measured using 51chromium-labeled autologous erythrocytes; TBV and PV were calculated from EV and total body hematocrit (peripheral venous hematocrit [HCT] x 0.89). Ideal blood volumes were calculated from nomograms based on body surface area and gender. Relationships between body volumes (percentage of ideal), simultaneously measured peripheral venous HCT and hemodynamic parameters heart rate, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index and systemic vascular resistance index were studied by stepwise regression. In 24 patients, blood volumes and hemodynamic parameters were also measured in the recovery room. HCT significantly correlated with EV at all three time periods (p less than 0.001), but the ability of HCT to predict EV in an individual patient was relatively poor (r = 0.50 preoperatively; r = 0.54 in recovery room and r = 0.66 24 hour postoperatively). By 24 hours postoperatively, EV had decreased to 78.3 +/- 2.4 percent of ideal EV (range of 47 to 112 percent). However, only two patients had HCT less than 30 despite the fact that 13 of 41 patients had an EV deficit of greater than 30 percent. No patient had a HCT of less than 25 percent. Hemodynamic parameters did not contribute to the prediction of EV, PV or TBV at any time. Two patients had myocardial infarctions postoperatively associated with 24 hour EV deficits of 18.5 and 29.6 percent. One patient died of a pulmonary embolus. Because of these findings, the concept of a "transfusion trigger" must be viewed with caution, since many patients undergoing vascular operations will have considerable EV deficits despite an "acceptable" HCT.

Age Factors↗
PubMed1989

The safety and therapeutic effectiveness of human red cells stored at -80 degrees C for as long as 21 years.

Human red cells frozen by various methods have been stored in the frozen state at -80 degrees C for as long as 21 years. This report discusses: red cells frozen with 42 percent weight per volume (wt/vol) glycerol in an ionic medium in a polyvinylchloride (PVC) plastic bag using the Cohn method; red cells frozen with 45 percent wt/vol glycerol in a low ionic medium in a PVC plastic bag using the Huggins method; red cells frozen with 40 percent wt/vol glycerol in an ionic medium in a polyolefin plastic bag using the Meryman-Hornblower method; and red cells frozen with 40 percent wt/vol glycerol in an ionic medium in a standard 600-ml or an elongated 800-ml PVC plastic primary collection bag with an adapter port using the Naval Blood Research Laboratory (NBRL) method. After frozen storage for as long as 21 years by the four methods described above, the thawed red cells were deglycerolized with 50 to 150 ml of 12 percent sodium chloride and 1.5 to 2.0 l of sodium chloride-glucose or sodium chloride-glucose-phosphate solution. After washing and storage at 4 degrees C for 24 hour, the red cells had a mean freeze-thaw-wash recovery value of 90 percent, a mean 24-hour posttransfusion survival value of 85 percent, a mean index of therapeutic effectiveness of 75 percent, normal or slightly impaired oxygen transport function, and minimal hemolysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticoagulants↗
PubMed1988

The 24-hour posttransfusion survival and lifespan of autologous baboon red cells treated with inositol hexaphosphate-polyethylene glycol or inositol hexaphosphate-adenosine triphosphate-polyethylene glycol to decrease oxygen affinity.

Baboon red cells were treated to reduce oxygen affinity by an osmotic-pulse procedure using dimethyl-sulfoxide. Inositol hexaphosphate (IHP) alone or IHP and adenosine triphosphate (ATP) were incorporated into the red cells in the presence of polyethylene glycol (PEG). The procedure produced variable increases in the red cell P50 value, i.e., the partial pressure of oxygen at which 50% of the hemoglobin was saturated. The effect of treatment of autologous baboon red cells on the 24-hour posttransfusion survival value and lifespan T50 value was measured using a double-label procedure. The data demonstrate that the increase in the P50 value of treated red cells was negatively correlated with the 24-hour posttransfusion survival value; the higher the P50 value, the poorer the 24-hour posttransfusion survival value. The 24-hour posttransfusion survival value for nontreated baboon red cells was 90% and the T50 value was 14 days. The IHP-ATP-PEG-treated red cells had significantly higher red cell ATP levels than did IHP-PEG-treated red cells. The 24-hour posttransfusion survival value was 68% for the IHP-ATP-PEG treated red cells and 52% for the IHP-PEG-treated red cells when the increase in P50 ranged from 10 to 20 mm Hg; the lifespan T50 value for both the IHP-ATP-PEG-treated red cells and the IHP-PEG-treated red cells was 15 days. Osmotic pulse treatment produced significant red cell injury manifested by the 24-hour posttransfusion survival value. However, modification of the RBC with IHP-PEG or IHP-ATP-PEG to decrease hemoglobin affinity for oxygen did not affect their lifespan.

Adenosine Triphosphate↗
PubMed1988

A clinical experience with ADSOL preserved erythrocytes.

This study was undertaken to determine how ADSOL (adenine, glucose, mannitol and sodium chloride) preservative affects the 24 hour post-transfusion survival values of human erythrocytes during storage at 4 degrees C. for 35, 42 and 49 days. The results show that acceptable 24 hour post-transfusion survival values were observed only after storage at 4 degrees C. for 35 days.

Adenine↗
PubMed1986

Coagulation assays and platelet aggregation patterns in human, baboon, and canine blood.

Coagulation assays in citrated plasma and platelet-aggregation patterns in citrated platelet-rich plasma were performed, using human, baboon, and canine blood. Similar fibrinogen concentrations, factor VIII antihemolytic factor (AHF) clotting protein concentrations, and thrombin times were seen in human and baboon plasma, whereas prothrombin times and activated partial thromboplastin times were significantly (P less than 0.017) more prolonged in baboon plasma than in human plasma. Canine plasma had significantly lower prothrombin times, activated partial thromboplastin times and thrombin times, and significantly higher concentrations of fibrinogen and factor VIII (AHF) clotting protein than did human plasma. The baboon factor VIII antigen cross-reacted with an antibody against human factor VIII antigen, whereas the canine factor VIII antigen did not. Human and canine platelets had similar aggregation patterns to adenosine diphosphate (ADP), whereas baboon platelets were less responsive to ADP than were human platelets. The response to collagen-induced aggregation in human and baboon blood was similar at concentrations of 0.190, 0.100, 0.050 and 0.025 mg/ml, whereas the response in human and canine blood was similar at concentrations of 0.190, 0.100, and 0.050 mg/ml. The lag time before aggregation with collagen was 2 to 3 times longer for canine platelets than for human platelets; human and baboon platelets had similar lag times. Baboon platelets were more responsive to arachidonic acid than were human platelets at concentrations of 0.25, 0.12, and 0.06 mg/ml, whereas canine platelets were less responsive than were human platelets at the highest concentration of 0.5 mg/ml. Human platelets were more responsive to epinephrine than were baboon or canine platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Quantitative differential agglutination method using the Coulter Counter to measure survival of compatible but identifiable red blood cells.

The method described here using a centrifuge and Coulter Cell Counter for the quantitative differential agglutination of human red cells uses commercial anti-A and anti-B antisera for the ABO system, and for the Rh system a commercial anti-D serum, a low ionic strength solution and an anti-human IgG antiserum. We compared this Coulter Counter method with the Technicon AutoAnalyzer method which utilizes bromelin and polyvinyl pyrrolidone, and anti-A, anti-B and anti-CD antisera, and found this new method to be the simpler of the two. The nonagglutinable count with the Coulter Counter was 1.07% for A1 red cells, 2.26% for A2 red cells, 1.06% for B red cells, and 1.78% for Rh-positive red cells, results similar to those seen with the Technicon AutoAnalyzer. Results with the Coulter Counter method were consistently accurate whether the ACD red cells were studied on the day of collection, after 10 days of 4 degrees C storage, or after 4 degrees C storage for up to 6 days followed by cryopreservation with 40% (w/v) glycerol at-80 degrees C, thawing and washing. In this study, red cell samples obtained from recipients who had received compatible but identifiable donor red cells were frozen with 40% glycerol and stored at-80 degrees C for 10 months, thawed and washed. Survival measurements on these washed previously frozen red cells were similar to the values in liquid-stored red cells.

Agglutination Tests↗
PubMed1981

Liquid preservation of baboon red blood cells in acid-citrate-dextrose or citrate-phosphate-dextrose anticoagulant: effects of washing liquid-stored red blood cells.

Autologous baboon RBC stored at 4 C in acid-citrate-dextrose (ACD) or in citrate-phosphate-dextrose (CPD) for 3 weeks after collection had 24-hour 51Cr posttransfusion survival values of about 77%. When 20-day-old ACD and CPD baboon RBC were washed and then stored at 4 C for 24 hours before autotransfusion, the 24-hour 51Cr posttransfusion survival values were about 81%. These values were similar to those seen in studies of human RBC preserved in an identical manner. Our results indicated that the baboon can be used to evaluate RBC preservation techniques before human volunteers are studied.

Animals↗
PubMed1981

Measurement of red blood cell volume, plasma volume, and total blood volume in baboons.

Red blood cell volume was measured directly in baboons by infusion of 51Cr-labeled autologous RBC, and was indirectly estimated from the plasma volume measured with 125I-labeled albumin and the total body hematocrit. The total body hematocrit was calculated from the peripheral venous hematocrit multiplied by a correction factor; for nonanemic baboons the correction factor was 0.87, and for anemic baboons, 0.75. Within 2 weeks after the phlebotomy (150 ml of blood), the baboon's RBC volume was restored to normal. Posttransfusion survival of baboon RBC can be measured accurately in nonanemic baboons; the preserved RBC can be labeled with 51Cr and the RBC volume of the baboon can be measured indirectly from the plasma volume measured with 125I-labeled albumin and the total body hematocrit.

Animals↗
PubMed1981

Freeze-preserved baboon red blood cells: effects of biochemical modification and perfusion in vitro.

Nonrejuvenated and rejuvenated baboon RBC were freeze-preserved with 40% (w/v) glycerol at -80 C. To prepare rejuvenated RBC, a 50-ml solution containing pyruvate, inosine, glucose, phosphate, and adenine was used and RBC were incubated with this solution before glycerolization and freezing. Appropriate steps were taken to minimize osmotic damage to the RBC during glycerolization and deglycerolization. Nonrejuvenated and rejuvenated cryopreserved RBC had freeze-thaw recovery values of 98%, freeze-thaw-wash recovery values of 92%, and 24-hour post-transfusion survival values of 85%. Some units of cryopreserved RBC were autotransfused after thawing, washing, and storage at 4 C for 24 hours. Other units were perfused in vitro before autotransfusion. After 24 hours of postwash storage, the RBC were concentrated by centrifugation and suspended in a plasma protein fraction and/or an electrolyte solution, and then were exposed to extracorporeal perfusion. Serious adverse effects were not observed on posttransfusion survival, function, or hemolysis in nonrejuvenated or rejuvenated baboon RBC as a result of perfusion in vitro.

2,3-Diphosphoglycerate↗
PubMed1980

Improved oxygen delivery to the myocardium during hypothermia by perfusion with 2,3 DPG-enriched red blood cells.

The oxygen affinity of red cells increases stepwise with temperature reductions below 37 degrees C. In vitro studies demonstrated that biochemically modified red cells with increased 2,3 diphosphoglycerate (2,3 DPG) (150% and 250% of normal) exhibited significantly less oxygen affinity at 24 degrees C than did unmodified cells. At 15 degrees C, significant attenuation of affinity was observed with 250%, but not 150%, of normal 2,3 DPG cells. Measurements made of isolated fibrillating dog hearts during perfusion at 24 degrees C alternately with unmodified (80% of normal 2,3 DPG) and modified (300% of normal 2,3 DPG) red cells demonstrated significantly greater oxygen consumption, higher coronary sinus partial pressures of oxygen and carbon dioxide, higher in vitro P50 values, and lower arterial and coronary sinus lactate levels during perfusion with modified as compared with unmodified cells. This evidence, indicating improved oxygen delivery to hypothermic dog hearts by red cells with 300% of normal 2,3 DPG activity, suggests that high 2,3 DPG cells might protect myocardial tissue in patients undergoing hypothermic cardiac operation.

Animals↗
PubMed1977

Physiologic effects of normal-or low-oxygen-affinity red cells in hypoxic baboons.

Baboons were bled one-third their red cell mass and were given homologous transfusions of red blood cells to restore the red cell volume. One group of baboons received red blood cells with a normal 2,3-diphosphoglycerate 2,3-DPG) level and normal affinity for oxygen, and in this group the 2,3-DPG level after transfusion was normal. The other group received red blood cells with a 160% of normal 2,3-DPG level and decreased affinity for oxygen, and in this group the 2,3-DPG level after transfusion was 125% of normal. In both groups of baboons, the inspired oxygen concentration was lowered and arterial PO2 tension was maintained at 55-60 mmHg for 2 h after transfusion. During the hypoxic state, systemic oxygen extraction was similar in the two groups, whereas oxygen saturation was lower in the high 2,3-DPG group than in the control animals. Cardiac output was significantly reduced 30 min after the arterial PO2 was restored to normal. These data indicate that red blood cells with decreased affinity for oxygen maintained satisfactory oxygen delivery to tissue during hypoxia.

Animals↗
PubMedDate not supplied

Occurrence of HBsAg, anti-HBs, the anti-CMV following the transfusion of blood products.

A retrospective study of the serum of 104 patients treated at Chelsea Naval Hospital between 1969 and 1972 was done. The donor blood products were not tested for the hepatitis B antigen before transfusion. The incidence of hepatitis B antigen following transfusion was about 2.8 per cent. The incidence of antibody to HBsAg prior to transfusion was 16 per cent, and about 27 per cent of the patients developed antibody to HBsAg following transfusion. The incidence of antibody to cytomegalovirus was about 22 per cent before transfusion, and 22 per cent of the patients developed complement fixing antibody against cytomegalovirus after transfusion. Since the patients received a variety of blood products it was not possible to determine retrsopectively which product, if any, produced the lowest incidence of hepatitis B antigen and transmission of cytomegalovirus.

Antibodies, Viral↗
PubMedDate not supplied

Liquid and freeze-preservation of dog red blood cells.

After storage in the liquid state at 4 C for up to three weeks, washing with sodium chloride solutions, and storage in a sodium chloride-glucose-phosphate solution for 24 hours at 4 C, dog red blood cells had excellent post-transfusion survival. After freeze-preservation with 40% W/V glycerol at -80 C or with 20% W/V glycerol at -150 C, thawing, washing with sodium chloride solutions, and storage in a sodium chloride-glucose-phosphate solution for 24 hours at 4 C, dog red blood cells had satisfactory recovery values in vitro, acceptable 24-hour post-transfusion survival and long-term survival values, and normal oxygen transport function. Controlled addition and removal of the cryoprotectant, glycerol, helped reduce the amount of osmotic damage to the red blood cells and enhanced freeze-preservation. Osmotic damage can also be prevented by warming the dog blood to a temperature of 22 +/- 2 C prior to centrifugation to concentrate the red blood cells and remove the plasma. This step enhances removal of the cold agglutinins. Another processing step used by the authors was to add a sodium chloride solution to the dog red blood cells before adding the glycerol solution in order to eliminate rouleaux formation.

Animals↗