G Cassidy's research while affiliated with University of Massachusetts Boston and other places

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Publications (30)


Anemia‐induced increase in the bleeding time:implications for treatment of nonsurgical blood loss
  • Article

November 2002

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19 Reads

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5 Citations

Transfusion

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George Cassidy

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Linda E. Pivacek

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[...]

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BACKGROUND: Preoperative bleeding time (BT) does not correlate with postoperative bleeding in patients subjected to surgical procedures. A significant positive correlation has been reported between the BT 2 hours after cardiopulmonary bypass surgery and the nonsurgical blood loss during the first 4 hours after bypass surgery. This study was done to investigate the effect of Hct and platelet count on the BT measurement in normal, healthy men and women.STUDY DESIGN AND METHODS: To assess the relative effect of RBCs and platelets on the BT, 22 healthy male and 7 healthy female volunteers were subjected to the removal of 2 units of RBCs (360 mL), followed by the return of the platelet-rich plasma (PRP) from both units and the infusion of 1000 mL of 0.9-percent NaCl. Four of the men and all seven women received their RBCs 1 hour after their removal. Shed blood levels of thromboxane B2 (TXB2), 6-keto prostaglandin F1, and peripheral venous Hct were measured. BTs were measured in 15 men and 13 women before and after a plateletpheresis procedure to collect 3.6 × 1011 platelets per unit.RESULTS: The 2-unit RBC apheresis procedure produced a 60-percent increase in the BT associated with a 15-percent reduction in the peripheral venous Hct and a 9-percent reduction in the platelet count. The plateletpheresis procedure produced a 32-percent decrease in the platelet count, no change in peripheral venous Hct, and no change in the BT. After the removal of 2 units of RBCs, the shed blood TXB2 level decreased significantly. Reinfusion of 2 units of RBCs restored the BT and restored the TXB2 level to the baseline levels.CONCLUSION: The acute reduction in Hct produced a reversible platelet dysfunction manifested by an increase in BT and a decrease in the shed blood TXB2 level at the template BT site. Return of the RBCs restored both the BT and the shed blood TXB2 level to normal. The platelet dysfunction observed with the reduction in Hct was due in part to a reduction in shed blood TXB2 and other, unknown mechanisms.

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Volume of RBCs, 24-and 48-hour posttransfusion survivals, and the lifespan of Cr-51 and biotin-X-N-hydroxysuccinimide (NHS)-labeled autologous baboon RBCs: effect of the anticoagulant and blood pH on Cr-51 and biotin-X-NHS elution in vivo
  • Article
  • Full-text available

April 2002

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102 Reads

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18 Citations

Transfusion

The RBC injury that occurs during collection of the first few milliliters of blood into the pH 5.0 ACD (NIH, Formula A) is referred to as the lesion of collection. The RBC injury was evaluated by labeling the ACD RBCs with (51)Cr and measuring the 24-hour posttransfusion survival. The effect of the acidification of ACD blood on the in vivo elution of (51)Cr from the RBC has not been reported. Baboon blood was collected in heparin and in ACD and CP2D at different ratios of blood to anticoagulant. ACD blood with a pH of 5.7 to 6.9 was labeled with (51)Cr. Heparinized blood with a pH of 7.4 was labeled with biotin-X-N-hydroxysuccinimide (NHS). ACD blood with a pH of 5.9 was labeled with both (51)Cr and biotin-X-NHS. The RBC volumes, 24- and 48-hour posttransfusion survivals, and lifespans (T50) were measured. The RBC volume of ACD blood with a pH ranging from 5.7 to 6.9 was not affected by (51)Cr labeling. (51)Cr-labeled ACD blood with a pH of 6.9 had an RBC volume that was significantly greater than that seen in heparinized blood with a pH of 7.4 labeled with biotin-X-NHS. In vivo elution of (51)Cr from the RBCs prepared from the ACD blood with a pH of 5.7 to 6.9 and in vivo elution of biotin-X-NHS from RBCs prepared from ACD blood with a pH of 5.9 were associated with reductions in 24- and 48-hour posttransfusion survivals and T50. The anticoagulant and the pH of the medium in which the RBCs were labeled with (51)Cr or biotin-X-NHS affected in vivo elution of the label from the RBCs and may reduce posttransfusion survival values.

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Anemia-induced increase in the bleeding time: Implications for treatment of nonsurgical blood loss

September 2001

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549 Reads

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253 Citations

Transfusion

Preoperative bleeding time (BT) does not correlate with postoperative bleeding in patients subjected to surgical procedures. A significant positive correlation has been reported between the BT 2 hours after cardiopulmonary bypass surgery and the nonsurgical blood loss during the first 4 hours after bypass surgery. This study was done to investigate the effect of Hct and platelet count on the BT measurement in normal, healthy men and women. To assess the relative effect of RBCs and platelets on the BT, 22 healthy male and 7 healthy female volunteers were subjected to the removal of 2 units of RBCs (360 mL), followed by the return of the platelet-rich plasma (PRP) from both units and the infusion of 1000 mL of 0.9-percent NaCl. Four of the men and all seven women received their RBCs 1 hour after their removal. Shed blood levels of thromboxane B(2) (TXB(2)), 6-keto prostaglandin F(1 alpha), and peripheral venous Hct were measured. BTs were measured in 15 men and 13 women before and after a plateletpheresis procedure to collect 3.6 x 10(11) platelets per unit. The 2-unit RBC apheresis procedure produced a 60-percent increase in the BT associated with a 15-percent reduction in the peripheral venous Hct and a 9-percent reduction in the platelet count. The plateletpheresis procedure produced a 32-percent decrease in the platelet count, no change in peripheral venous Hct, and no change in the BT. After the removal of 2 units of RBCs, the shed blood TXB(2) level decreased significantly. Reinfusion of 2 units of RBCs restored the BT and restored the TXB(2) level to the baseline levels. The acute reduction in Hct produced a reversible platelet dysfunction manifested by an increase in BT and a decrease in the shed blood TXB(2) level at the template BT site. Return of the RBCs restored both the BT and the shed blood TXB(2) level to normal. The platelet dysfunction observed with the reduction in Hct was due in part to a reduction in shed blood TXB(2) and other, unknown mechanisms.


In vitro and in vivo measurements of gamma-radiated, frozen, glycerolized RBCs

May 2001

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19 Reads

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10 Citations

Transfusion

Transfusion-associated GVHD results from the presence of viable lymphocytes in transfused allogeneic blood components. Viable immunocompetent lymphocytes have been detected in RBCs that were frozen with glycerol and washed before transfusion. The study reported here assessed the effect of irradiation on human RBCs frozen with 40-percent (wt/vol) glycerol and stored at -80 degrees C. In vitro and in vivo testing was done on human RBCs that were frozen with 40-percent (wt/vol) glycerol at -80 degrees C, with some units exposed to 2500 cGy of gamma radiation and others not irradiated, and that, after thawing and washing, were stored in a sodium chloride-glucose solution at 4 degrees C for 3 days before autologous transfusion. The glycerol-frozen RBCs treated with 2500 cGy before deglycerolization had a mean freeze-thaw-wash recovery of 87 percent and a mean 24-hour posttransfusion survival of 86 percent after storage for 3 days at 4 degrees C in a 0.9-percent NaCl and 0.2-percent glucose solution. For the nonirradiated units, the mean freeze-thaw-wash recovery was 85 percent and the mean 24-hour posttransfusion survival was 83 percent. These data show similar, acceptable results for RBCs frozen with 40-percent (wt/vol) glycerol at -80 degrees C and treated in the frozen state with 2500 cGy of gamma radiation and for RBCs that were not irradiated, all of which were washed and then stored in a sodium chloride-glucose solution for 3 days before autologous transfusion.


In vitro and in vivo measurementsof gamma‐radiated, frozen, glycerolized RBCs

April 2001

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12 Reads

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10 Citations

Transfusion

BACKGROUND : Transfusion‐associated GVHD results from the presence of viable lymphocytes in transfused allogeneic blood components. Viable immunocompetent lymphocytes have been detected in RBCs that were frozen with glycerol and washed before transfusion. STUDY DESIGN AND METHODS : The study reported here assessed the effect of irradiation on human RBCs frozen with 40‐percent (wt/vol) glycerol and stored at –80°C. In vitro and in vivo testing was done on human RBCs that were frozen with 40‐percent (wt/vol) glycerol at –80°C, with some units exposed to 2500 cGy of gamma radiation and others not irradiated, and that, after thawing and washing, were stored in a sodium chloride‐glucose solution at 4°C for 3 days before autologous transfusion. RESULTS : The glycerol‐frozen RBCs treated with 2500 cGy before deglycerolization had a mean freeze‐thaw‐wash recovery of 87 percent and a mean 24‐hour posttransfusion survival of 86 percent after storage for 3 days at 4°C in a 0.9‐percent NaCl and 0.2‐percent glucose solution. For the nonirradiated units, the mean freeze‐thaw‐wash recovery was 85 percent and the mean 24‐hour posttransfusion survival was 83 percent. CONCLUSION : These data show similar, acceptable results for RBCs frozen with 40‐percent (wt/vol) glycerol at –80°C and treated in the frozen state with 2500 cGy of gamma radiation and for RBCs that were not irradiated, all of which were washed and then stored in a sodium chloride‐glucose solution for 3 days before autologous transfusion.


In vitro and in vivo measurements of human RBCs frozen with glycerol and subjected to various storage temperatures before deglycerolization and storage at 4°C for 3 days

April 2001

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25 Reads

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14 Citations

Transfusion

This study was designed to assess the effects of changes in storage temperature of frozen RBCs such as might occur during a malfunction of the -80 degrees C mechanical freezer or during shipment. Fifteen participants donated blood for autologous transfusion of RBCs; all RBCs were frozen with 40-percent (wt/vol) glycerol. Five subjects received RBCs that were stored at -80 degrees C alone before transfusion. Five subjects received RBCs that were stored initially at -80 degrees C, then at -40 degrees C for 4 weeks, and finally at -80 degrees C before transfusion. Five subjects received RBCs that were stored at -80 degrees C, then at -20 degrees C for 2 weeks, and finally at -80 degrees C before transfusion. After deglycerolization, the RBCs were stored at 4 degrees C in a sodium chloride-glucose solution for 3 days before transfusion. No significant differences were observed in freeze-thaw recovery, freeze-thaw-wash recovery, 24-hour posttransfusion survival, index of therapeutic effectiveness, or RBC ATP levels. Greater hemolysis and reduced RBC K+ levels were observed in the units stored at -80 degrees C/-40 degrees C/-80 degrees C and in those stored at -80 degrees C/ -20 degrees C/-80 degrees C compared with the units stored at -80 degrees C alone, but these differences did not affect the 24-hour posttransfusion survival. The results of this study indicated that RBCs frozen with 40-percent (wt/vol) glycerol can be stored at -40 degrees C for 4 weeks or at -20 degrees C for 2 weeks between periods of frozen storage at -80 degrees C with satisfactory results.


24-hour 51Cr post-transfusion survival, 51Cr life span and haemolysis of red blood cells stored at 4 degrees C for 56 days in AS-3

February 2001

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7 Reads

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10 Citations

Vox Sanguinis

Red blood cells (RBC) were collected either by a manual method using a 16-gauge needle or by an apheresis procedure using an 18-gauge needle, and were stored at 4 degrees C in a solution of CP2D (anticoagulant)/AS-3 (Nutricel) for 56 days. The purpose was to compare the outcome of the autotransfused red cells collected by both techniques. Five healthy male volunteers were studied on two occasions. The autotransfusions of the manual and apheresed RBC resulted in a mean 24-h post-transfusion survival of 71%, a normal mean 51Cr RBC life span, a 2,3 DPG level that was less than 10% of normal, and 0.6% haemolysis. Whether collected manually or by apheresis, the outcomes were similar for RBC stored at 4 degrees C for 56 days in CP2D/AS-3.


24-Hour 51Cr post-transfusion survival, 51Cr life span and haemolysis of red blood cells stored at 4 °C for 56 days in AS-3

January 2001

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11 Reads

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11 Citations

Vox Sanguinis

Red blood cells (RBC) were collected either by a manual method using a 16-gauge needle or by an apheresis procedure using an 18-gauge needle, and were stored at 4 °C in a solution of CP2D (anticoagulant)/AS-3 (Nutricel) for 56 days. The purpose was to compare the outcome of the autotransfused red cells collected by both techniques. Five healthy male volunteers were studied on two occasions. The autotransfusions of the manual and apheresed RBC resulted in a mean 24-h post-transfusion survival of 71%, a normal mean 51Cr RBC life span, a 2,3 DPG level that was less than 10% of normal, and 0·6% haemolysis. Whether collected manually or by apheresis, the outcomes were similar for RBC stored at 4 °C for 56 days in CP2D/AS-3.


Posttransfusion survival (24-hour) and hemolysis of previously frozen, deglycerolized RBCs after storage at 4 degrees C for up to 14 days in sodium chloride alone or sodium chloride supplemented with additive solutions

December 2000

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43 Reads

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9 Citations

Transfusion

Previously frozen human RBCs currently are glycerolized and deglycerolized by the use of open systems that limit storage of the deglycerolized RBCs at 4 degrees C to only 24 hours. Healthy male volunteers who met AABB requirements for blood donors (n = 38) were studied. A volume of 450 mL of blood was collected into CPDA-1. The RBC concentrates were stored at 4 degrees C for 3 to 6 days before being frozen with 40-percent (wt/vol) glycerol and stored at -80 degrees C. The RBCs were deglycerolized, resuspended in 0.9-percent sodium chloride and 0.2-percent glucose (SG) solution or SG solution supplemented with AS-1, AS-3, or AS-5, and stored in the resuspension medium at 4 degrees C for 14 days. The mean +/- SD freeze-thaw-wash process recovery was 90.0 +/- 4.0 percent for all 38 units. The mean 24-hour posttransfusion survival value was 79 percent for deglycerolized RBC stored at 4 degrees C for 7 days in SG alone, SG plus AS-3, or SG plus AS-5. Deglycerolized RBC that were stored at 4 C for 14 days in SG supplemented with AS-1, AS-3, or AS-5 had a mean 24-hour posttransfusion survival of 74 percent. After 7 days of storage of deglycerolized RBCs in SG alone, the mean hemolysis was 3. 7 percent. After 14 days of storage of deglycerolized RBCs in SG supplemented with AS-1, AS-3, or AS-5, the mean hemolysis was 2.5 percent. The levels of hemolysis did not correlate with the 24-hour posttransfusion survival values.


The survival, function, and hemolysis of human RBCs stored at 4°C in additive solution (AS-1, AS-3, or AS-5) for 42 days and then biochemically modified, frozen, thawed, washed, and stored at 4°C in sodium chloride and glucose solution for 24 hours

November 2000

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53 Reads

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38 Citations

Transfusion

BACKGROUND: A study was done to assess the quality of RBCs stored at 4°C in AS-1, AS-3, or AS-5 for 42 days before biochemical modification and freezing. STUDY DESIGN AND METHODS: RBCs were stored at 4°C for 42 days in AS-1, AS-3, or AS-5 and then biochemically modified with pyruvate, inosine, phosphate, and adenine solution (Rejuvesol), frozen with 40-percent (wt/vol) glycerol, and stored at –80°C for at least 2 months. The RBCs were deglycerolized by the use of a cell washer (Haemonetics 115), and stored for 24 hours at 4°C in a 0.9-percent sodium chloride and 0.2-percent glucose solution before the autologous transfusion. RESULTS: The mean freeze-thaw-wash recovery process produced RBC recovery values of 85 percent, with the mean 24-hour posttransfusion survival at 75 percent, and the mean index of therapeutic effectiveness at 64 percent for the RBCs stored at 4°C in AS-1, AS-3, or AS-5 for 42 days before biochemical modification and freezing. All the units exhibited normal or slightly higher than normal 2,3 DPG levels after deglycerolization and postwash storage at 4°C for 24 hours. CONCLUSION: RBCs stored in AS-1, AS-3, or AS-5 at 4°C for 42 days and then biochemically modified with pyruvate, inosine, phosphate, and adenine and glycerolized, frozen, washed, and stored at 4°C for 24 hours before autologous transfusion had acceptable in vitro and in vivo measurements.


Citations (18)


... AS-3 (Nutricel) is an excellent medium for the 4∞C storage of liquid-preserved and washed previously frozen RBCs. 3,4,[10][11][12][13] Previous studies have shown that the process of glycerolizing and deglycerolizing liquid-preserved and cryopreserved RBCs reduced the total number of WBCs in the unit. [14][15][16][17][18] In this study, measurements made on 42 units on the day of deglycerolization with the Nageotte chamber with Turk's solution showed a mean total number of WBCs of 1.1 ¥ 10 7 . ...

Reference:

The in vitro quality of red blood cells frozen with 40 percent (wt/vol) glycerol at -80 degrees C for 14 years, deglycerolized with the Haemonetics ACP 215, and stored at 4 degrees C in additive solution-1 or additive solution-3 for up to 3 weeks
24-Hour 51Cr post-transfusion survival, 51Cr life span and haemolysis of red blood cells stored at 4 °C for 56 days in AS-3
  • Citing Article
  • January 2001

Vox Sanguinis

... Étant donné l'absence de données concluantes, il est prudent de mesurer l'hémoglobine tout au long de la réanimation afin d'éviter les conséquences d'une quantité insuffisante ou excessive de transfusions (p. ex., hypoperfusion des organes, coagulopathie liée à l'anémie, surcharge liquidienne) 41 . Les paramètres cibles de la figure 3 visent le maintien d'un taux d'hémoglobine supérieur à 60 g/L durant la réanimation et la réduction du nombre de transfusions superflues, définies par un taux d'hémoglobine supérieur à 110 g/L 24 heures après l'épisode hémorragique 19 . ...

Anemia‐induced increase in the bleeding time:implications for treatment of nonsurgical blood loss
  • Citing Article
  • November 2002

Transfusion

... 5,6 Following centrifugation, the RBCs are then stored in one of multiple available additive solutions (e.g., AS-1, AS-3, AS-5, or AS-7). 5,7,8 The contents of AS-1 are also shown in Table 1. While the current blood storage procedure has been in place since the 1970s, there are many reports showing adverse effects of storage over time on the RBC's chemical and physical properties. ...

The survival, function, and hemolysis of human RBCs stored at 4°C in additive solution (AS-1, AS-3, or AS-5) for 42 days and then biochemically modified, frozen, thawed, washed, and stored at 4°C in sodium chloride and glucose solution for 24 hours
  • Citing Article
  • November 2000

Transfusion

... Moreover, the most vulnerable cells are likely of greatest interest. RBC assessment following cryopreservation has focused on basic in vitro analyses (hemolysis [2,3,21], morphologic [2,33], rheologic [34], osmotic [2,33,34], surface marker [35], and biochemical [2,3,33]) and on in vivo survival [3,21,36], rather than on physiologic function (O 2 transport, NO processing, vasoreactivity, and metabolism). Given new understanding of the pivotal role played by RBCs in vasoregulation [37], such analyses are relevant as well. ...

The safety and therapeutic effectiveness of human red cells stored at — 80°C for as long as 21 years
  • Citing Article
  • July 1989

Transfusion

... When the RBC lysate is covalently linked by adenosine triphosphate (ATP) or pyridoxal phosphate and purified by agarose nucleophilic chromatography, it can cause vasoconstriction of the coronary artery. This may be caused by the covalent modification, or that nucleophilic chromatography removes membrane phospholipids and denatured protein aggregates (Vogel et al., 1987;Lang et al., 1990). ...

Reduced coronary vasoconstrictor activity of hemoglobin solutions purified by ATP-agarose affinity chromatography
  • Citing Article
  • August 1987

Life Sciences

... Capturing NO produced by ECs, oxyHb inhibits its paracrine diffusion into vascular smooth muscle cells and alters vasomotricity [28,107]. Many studies have shown this alteration of vascular tonus resulted in systemic arterial or pulmonary hypertension, as well as a modification of organ perfusion [108][109][110]. Inhibition of the NO/Hb interaction, in a hemoglobin mutagenesis rat model, has shown decreased vasoconstriction and arterial hypertension after infusion of free hemoglobin [111]. ...

Coronary constrictor effect of stroma-free hemoglobin solutions
  • Citing Article
  • September 1986

American Journal of Physiology-Legacy Content

... Even moderate perioperative hypothermia can result in potentially serious complications [1]. These include increased mortality, cardiac complications such as arrhythmias and myocardial ischemia, coagulation disorders as well as increased transfusion requirements and oxygen consumption [2,3,4,5]. Postoperative shivering, changes in potassium serum concentrations and peripheral vasoconstriction are also relevant side effects of perioperative hypothermia [6]. ...

Hypothermia-induced Reversible Platelet Dysfunction
  • Citing Article
  • March 1987

Annals of Surgery

... Another clinical observation was that following the transfusion of RBC which increased the peripheral red blood cell volume to the extremities, the edema in the tissues of the extremities disappeared. The reduction in the tissue edema in the extremities was associated with an increase in the plasma volume [9]. ...

Increase in plasma volume after the transfusion of washed erythrocytes
  • Citing Article
  • February 1986

Surgery, Gynecology & Obstetrics

... Studies that sought to evaluate rejuvenation as a clinical intervention therefore washed red cells postrejuvenation and prior to transfusion, using commercially available mechanical cell washers. The resuspension solution in early experiments was 0Á9% sodium chloride solution, with the later addition of glucose and ultimately phosphate to allow postrejuvenation storage for longer periods [36]. Rejuvenationwashing recovery in vitro was 98% in these experiments, where red cells were stored for 24 h and 72 h postwash, with in vivo 24-h post-transfusion survivals of 82% and 79%, respectively [36]. ...

The 24-hour posttransfusion survival, oxygen transport function, and residual hemolysis of human outdated-rejuvenated red cell concentrates after washing and storage at 4°C for 24 to 72 hours
  • Citing Article
  • July 1984

Transfusion

... [7][8][9][10][11][12] Although investigations from the basic science literature have suggested that mild hypothermia might protect against thrombosis due to inhibition of platelet function and the clotting cascade, results from these studies have been discordant with clinical studies. [13][14][15] Thus, the question arises whether intraoperative core body temperature may be a predictive factor of VTE after CAWR. ...

Effects of temperature on the BT and clotting time in normal male and female volunteers

Critical Care Medicine