SHOCK

Shock is a systemic state of low tissue perfusion, which is inadequate for normal cellular respiration

With insufficient delivery of Oxygen and glucose, cells switch from aerobic to anaerobic Metabolism. If perfusion is not restored in a timely fashion, cell Death ensues

As perfusion to the tissues is reduced, cells are deprived of oxygen and must switch from aerobic to anaerobic metabolism.

Theproduct of anaerobic respiration is not carbon dioxide but lacticacid. When enough tissue is underperfused, the accumulation of

lactic acid in the blood produces systemic metabolic acidosis.As glucose within cells is exhausted, anaerobic respiration

ceases and there is failure of the sodium/potassium pumps in thecell membrane and intracellular organelles. Intracellular lysosomes

release autodigestive enzymes and cell lysis ensues.Intracellular

contents, including potassium, are released into thebloodstream.

Classification of shockHypovolaemic

CardiogenicObstructiveDistributive

EndocrineNeurogenic

Severity of shock

Compensated shockDecompensationMild shockModerate shockSevere shock

BLOOD TRANSFUSION

Blood transfusion Is the process of receiving blood products

into one's circulation intravenously. Transfusions are used in a variety of

medical conditions to replace lost components of the blood.

Early transfusions used whole blood, but modern medical practice commonly uses only components of the blood, such as red blood cells, white blood cells, plasma, clotting factors, and platelets.Contents

Definition of blood

Is a tissue fluid circulating throw the heart, arteries, capillaries and veins, carrying nutrients and O2 and remove waste product and CO2.

Functions of blood: 1- carrying of nutrients and waste product 2- immunity of all vital processes 3- regulation of body temperture 4- haemostasis, rest of bleeding by

physiological properties ( coagulation ) 5- important in tissue healing.

TESTING PRE TRASFUSIONBlood groupingABO and RhSelection of doner blood and

crossmatchingAntibody screeningBoth by direct agglutination test(for

detection of IGM antibodies) OR indirect antiglobulin test (for IgG antibodies)

Copatiplity check

Blood pack information :- Frist name Fore name date of birthHospital number During transfusion observe the pt

15m before and after starting each pack

INDICATION Following trauma which cause sever blood

loss , or hrg from a pathological lesion e.g. from GIT

During major surgery e.g. abdomenoperiotonial or cardiothoracic surgery

Following sever burn to replace fluids and proteins

Post operation in pt who become anemic Preoperative in anemic pt and no time for iron Prophylactic prior to surgery in pt with

hemophilia , thrombocytopenia or liver disease

Preparation of bld for transfusion

Donor should be fit and with no evidence of infection (hepatitis , HIV)

Bld collected into sterile prepared plastic bag with needle and plastic tube attached in a complete closed sterile unit

With the donor lying on a couch ,a sphengomanometer inflated to a pressure of 70-80 mmHg

410 ml of bld is allowed to run into a bag containing 75ml of anticoagulant solution CPD

Blood is withdrawn from the donor and mixed with a citrate solution to prevent coagulation by binding calcium.

The solutions used commonly are citrate phosphate dextrose (CPD), citrate phosphate double dextrose (CP2D), and citrate phosphate dextrose adenine (CPDA-1).

Blood storage

Should store in special blood bank refrigerators controlled at 4c +or- 2c

Bld allowed to stand in higher temp for more than 2hrs is in danger to transmit infection

CPD bld has a half of 3 wk and CPDA for 1-5wks

RBCs suffer temporary reduction after 24-72 hrs their ability to release oxygen ,so if pt require argent and massive transfusion give 1or2 units of bld that less than 7 days old

Blood fraction

Whole Blood

Storage of whole blood precludes the production of components and is highly inefficient.

Whole blood is thus unavailable in most blood banks in the United States because oxygen-carrying capacity and replacement of volume can be achieved with packed RBCs and crystalloid solutions

Red Blood Cells

Packed RBCs halfe life of 42 days. With longer storage, fewer than 70% of the RBCs remain

viable in circulation 24 hours after transfusion. Platelets degenerate at refrigerator temperatures, so

banked packed RBCs contain essentially no functioning platelets.

The levels of factors V and VIII decrease significantly over 24 hours at 1°C to 6°C, although the levels of other factors remain essentially unchanged.

Packed RBCs provide oxygen-carrying capacity and maintain oxygen delivery provided intravascular volume and cardiac function are adequate

Transfusion Guidelines for Red Blood Cells

Hemoglobin <5 g/dL or acute blood loss in an otherwise healthy patient with signs and symptoms of decreased oxygen delivery with two or more of the following:

Estimated or anticipated acute blood loss of >15% of total blood volume (750 mL in 70-kg male)

Diastolic blood pressure <60 mm Hg Systolic blood pressure drop >30 mm Hg from baseline Tachycardia (>100 beats/min) Oliguria/anuria Mental status changes

Platelets

Platelet transfusions are indicated for patients suffering from or at significant risk of bleeding owing to thrombocytopenia and/or platelet dysfunction.

Besides monitoring the patient for evidence of improved hemostasis, follow-up platelet counts at 1 hour and 12 or 24 hours can provide an estimate of platelet survival.

After platelet transfusion, the platelet count obtained at 1 hour should increase at least 5000 platelets/mm3 for each unit of platelets

0 day7 days14 days21 days

%of red cell viability

95%90%85%75%

%of platelet viability

95%0%0%0%

%of coagulation

factor V &XIII

95%30%30%30%

Leukocyte Concentrate

Leukocyte transfusions are indicated in profound granulocytopenia (<500/mm3 ) with evidence of infection (e.g., positive blood culture, persistent temperature above 38.5°C) unresponsive to antibiotic therapy.

Daily transfusions are given until the infection is under control or the granulocyte count is greater than 1000/mm3 .

Donors typically premedicated with corticosteroids to increase the number of circulating granulocytes.

Fresh Frozen Plasma(FFP)

FFP is used to replace labile factors in patients with coagulopathy and documented factor deficiency. This condition may derive from liver dysfunction, congenital absence of factors, or transfusion of factor-deficient blood products.

A unit of FFP contains near-normal levels of all factors, including about 400 mg of fibrinogen.

The PT and the aPTT can be used to assess patients for FFP transfusion and to follow the efficacy of administered FFP.

Cryoprecipitate

Cryoprecipitate is useful in treating factor deficiency (hemophilia A), von Willebrand’s disease, and hypofibrinogenemia and may help treat uremic bleeding.

Each 5- to 15-mL unit contains 80 units of factor VIII, about 200 mg of fibrinogen

Packed red cells : in pt with chronic anemia in elderly

and children

Platelet rich plasma : In pt with thrombocytopenia

Platelet concentrate : thrombocytopenia

Plasma : in burn pt

COMPLICATIONS OF BLOOD TRANSFUSION Transfusion Reactions:

1- hemolytic reaction 2-nonhemolytic reactions with febrile and allergic nonhemolytic subtypes.Hemolytic reactions :- are caused by complement-mediated destruction of

transfused RBCs secondary to preexisting antibodies, and the severity of the reaction is determined by the degree of complement activation and cytokine release.

Severe acute hemolytic reactions generally involve the transfusion of ABO-incompatible blood, with fatalities occurring in 1 in 600,000 units.

C|F of Transfusion Reactions

Produce hypotension, compromise renal blood flow, activate coagulation, and lead to DIC.

Signs and symptoms include pain and redness along the infused vein, chest tightness and pain, a feeling of doom, hypotension, oozing from intravenous sites, oliguria, chills, fever, hemoglobinemia, and hemoglobinuria.

In the unconscious patient, hypotension, hemoglobinuria, and diffuse oozing may be the only clues.

Treatment ````````````````````````````````````````````

```````````````````````````````````````` The patient should receive aggressive fluid resuscitation to correct hypotension and maintain renal blood flow.

A brisk diuresis may be initiated with mannitol or furosemide, and agents that increase renal blood flow should be considered.

Give I V hydrocortison

Delayed hemolytic reactions tend to present 5 to 10 days after transfusion

Allergic nonhemolytic reactions Allergic nonhemolytic reactions are generally believed to be

caused by recipient antibodies to infusing donor plasma proteins. C/F:- slight rash or urticaria to hemodynamic instability with

bronchospasm and anaphylaxis. Allergic reactions may be prevented by premedication with

diphenhydramine. Recipient antibodies against antigens on donor leukocytes or

platelets cause febrile nonhemolytic reactions. Fevers and chills characterize these reactions shortly after the

transfusion has started. An acute hemolytic reaction and bacterial contamination of the

unit should be excluded. Treatment consists of antipyretics and transfusion of leukocyte-

depleted blood components when pharmacotherapy fails.

INFECTIONS TRANSMMITED BY BLOOD TRANSFUSION HBV & HCV CMV HIV Human T-cell leukemia virus (HTLV) types I and

II Others: syphilis, malaria, and infection with ,

Trypanosoma cruzi, Staphylococcus aureus, Staphylococcus epidermidis, or Klebsiella pneumoniae

Transfusion-Related Acute Lung Injury Fatal pulmonary edema associated with transfusion

was first described in 1951. is a clinical syndrome associated with the transfusion

of all blood components, but especially whole blood, packed red cells, and FFP.

The incidence is estimated to be 1 case per 5000 units transfused, but the syndrome is often underdiagnosed.

It is believed to be the third most common cause of fatal transfusion reactions.

characterized by the onset of dyspnea, hypotension, hypoxemia, fever, and bilateral noncardiogenic pulmonary edema within 4 hours of transfusion.

Graft-Versus-Host Reaction

Blood transfusion exposes the recipient to many cells and proteins from the donor.

When immunologically competent lymphocytes are introduced into an immunocompromised patient, a graft-versus-host reaction can occur.

The functional donor lymphocytes attack recipient tissues, notably the bone marrow, causing aplasia.

Patients present with fever, rash, nausea, vomiting, diarrhea, liver function test abnormalities, and depressed cell counts.

Congestive heart failure Result from too large infusion of bld Occur in elderly or in absence of CVS

sufficiency

Thrombophlebitis

Inflammation of superficial veins

Other complications

Immunomodulation Hypocalcemia Acid-Base Changes Iron overload Hypothermia