Blood, packed red cells

If goal not achieved with fluid resuscitation and the hematocrit is <30%, then transfuse packed red blood cells to achieve a hematocrit >30%... 

Use of Packed Red Blood Cell Transfusions and Erythropoietin in Critically 111 Patients"... 

Potential adverse effects of packed red blood cell (PRBCs) transfusions... 

FIGURE 10-4. Treatment algorithm for the management of moderate to severe hypovolemia. BP, blood pressure CVP, central venous pressure ECG, electrocardiogram MAP, mean arterial pressure PA, pulmonary artery PAOP, pulmonary artery occlusion pressure PRBCs, packed red blood cells SBP, systolic blood pressure. 

Transfuse with packed red blood cells and platelets as needed... 

PRBC Packed red blood cells RUL Right upper lobe... 

Packed red blood cells contain hemoglobin that increases the 02-carrying capacity of blood, thereby increasing 02 delivery to tissues. This is a function not performed by crystalloids or colloids. Packed red cells are usually indicated in patients with continued deterioration after volume replacement or obvious exsanguination. The product needs to be warmed before administration, especially when used in children. 

In patients with significant blood loss (hematocrit of 25% or less), blood should be given. This is generally in the form of packed red blood cells. 

Fig. 28. 300-MHz hyperfine-shifted exchangeable proton resonances of proximal histidyl residues of the a and 0 chains of deoxy-Hb A. (A) 3.0 mM Hb A in 0.1 M Bis—Tris (95% deoxy-Hb A) (B) freshly lysed red blood cells, 4.7 mM Hb A (90% deoxy-Hb A) (C) freshly packed red blood cells (75% deoxy-Hb A). The broad dips in spectra B and C are due to membranes and other cell components. [From Yao et al. (1986)].

Allergic reaction due to streptokinase overdose should be treated with corticosteroids and histamines. Severe hemorrhage requires discontinuation of streptokinase. Packed red blood cells are preferable for blood-replacement therapy, and volume expansion is advisable. Streptokinase may be used with caution with heparin, allopurinol, sex hormones, sulfonamides, tetracyclines, and dextran. 

Q5 The term haematocrit refers to the percentage of total blood volume occupied by packed red blood cells (erythrocytes). In males the haematocrit is normally 40-54% Chandra s packed cell volume is higher than normal 59%. Development of erythrocytes takes place in red bone marrow and is controlled by the hormone erythropoietin, which is produced by kidney cells. The major stimulus for erythropoietin production and release is hypoxia. 

S.) Packed red blood cells are indicated when the blood loss is >25% (Hb <7-8 g/dl). In this event, at least 3 or 4 units of blood should be readily available, and sufficient reserves must be on hand. An Hb value of 10 -11 g/dl is considered to be an adequate transfusion target. Degradation of the citrate normally present in conserved blood is delayed in the case of cirrhosis, so that a substitution of 10 ml calcium per 4 units of erythrocyte concentrate is advisable. In order to avoid transfusion acidosis (pH < 7.2), 40 mval bicarbonate are administered for every (4 or) 5 transfusions. 

The question concerning the use of semi-invasive or surgical measures arises once definitive haemostasis has been achieved. This depends on the liver function in each case and a careful review of the individual risk factors and behaviour as well as an assessment of the indications. Variceal bleeding that has proved to be unresponsive to haemostatic efforts over a period of time exceeding 2 days (with a daily application of more than four units of packed red blood cells) in spite of all conservative measures must be subjected to semi-invasive or surgical therapy. This also applies to an early recurrence of bleeding. 

Packed Red Blood Cells Contain all blood products except plasma and are used to decrease circulatory overload and reduce the risk of reactions to antigens contained in plasma... 

No studies w ere located that described the distribution of formaldehyde or its metabolites in humans after inhalation exposure. Several studies are available that describe the distribution of formaldehyde in laboratory animals. Heck et al. (1983) examined the fate of C-formaldchydc in Fischer 344 rats. Rats w ere exposed by inhalation to C-formaldehyde at 8 ppm for 6 hours. Concentrations of total radioactivity in the w hole blood and plasma were monitored for 8 days. The terminal half-life of the C w as approximately 55 hours, w hich was considerably longer than the known half-life of formaldehyde (about 1.5 minutes in monkeys), indicating both the metabolism of C-CHjO to other molecules (i.e., fonnate) and incorporation into other molecules. Radioactivity in the packed blood cell fraction was multiphasic it initially increased during exposure, declined during the first hour postexposure, then began to increase again, reaching a maximum at approximately 35 hours postexposure. The terminal phase of the packed red blood cell fraction had a very slow decline in radioactivity, which would likely continue for several weeks after exposure ended (half-life >55 hours). 

Laboratory abnormalities such as increased packed red blood cell volume and total protein, magnesium, and calcium levels are a result of hemoconcentration. Hypoglycemia, seizures, fever, and mental alterations are seen more often in children, perhaps as a reflection of the greater degree of dehydration and electrolyte losses observed with diarrhea in children. Other complications include metabolic acidosis, prerenal azotemia, iatrogenic water intoxication from overrehydration, and aspiration pneumonia. Children, the elderly, and pregnant women are at an increased risk of complications due to cholera. 

In patients with significant blood loss, blood transfusion may be indicated. This is generally in the form of packed red blood cells. The criteria for blood transfusion are controversial, but a hematocrit of 25% generally is accepted. In the individual patient, the decision is often determined by the overall chnical status and the ability of the patient to compensate for the reduction in oxygen-carrying capacity associated with an acute anemia. Additional blood component therapy with fresh frozen plasma or platelets is also based on the needs of the individual patient. Aggressive fluid therapy often must be continued in the postoperative period because fluid will continue to sequester in the peritoneal cavity, bowel wall, and lumen. 

Heparin therapy for DIG is discouraged by most clinicians because there is no evidence that heparin prolongs the survival of patients despite its effect on the hypercoagulable condition found in DIG. Hemorrhage is best managed by the replacement of clotting factors, platelets, and packed red blood cells. 

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