Acute and Chronic Blood Loss Anemia PDF

6/28/2024 ACUTE AND CHRONIC BLOOD LOSS ANEMIA AND ANEMIAS ASSOCIATED WITH SYSTEMIC DISORDERS...

6/28/2024 ACUTE AND CHRONIC BLOOD LOSS ANEMIA AND ANEMIAS ASSOCIATED WITH SYSTEMIC DISORDERS CHAPTER 12 PREAMBLE PowerPoints are a general overview and are provided to help students take notes over the video lecture ONLY. PowerPoints DO NOT cover the details needed for the Unit exam Each student is responsible for READING the TEXTBOOK for details to answer the UNIT OBJECTIVES Unit Objectives are your study guide (not this PowerPoint) Test questions cover the details of UNIT OBJECTIVES found only in your Textbook! 1  6/28/2024 ACUTE BLOOD LOSS ANEMIA #1 Etiology The acute loss of blood is usually associated with traumatic conditions such as an accident or severe injury. Occasionally, acute blood loss may occur during or after surgery. ACUTE BLOOD LOSS ANEMIA #2 Physiology Acute blood loss does not produce an immediate anemia. A severe hemorrhage or rapid blood loss amounting to more than 20% of the circulating blood volume reduces an individual’s total blood volume and produces a condition of shock and related cardiovascular problems. In acute blood loss, the body itself adjusts to the situation by expanding the circulatory volume, which produces the subsequent anemia. 2  6/28/2024 ACUTE BLOOD LOSS VERSUS CHRONIC BLOOD LOSS #1 Laboratory findings Acute (occurs within 24 to 48 hours) versus chronic (occurs over periods of months to years) look very different. ACUTE BLOOD LOSS VERSUS CHRONIC BLOOD LOSS #2 The physiology of acute and chronic blood loss are also very different, so it’s reasonable to say that their physiologic adaptations are also different. 3  6/28/2024 ACUTE BLOOD LOSS ANEMIA #3 Laboratory findings The earliest hematological change in acute blood loss is a transient fall in the platelet count, which may rise to elevated levels within 1 hour (inflammatory reaction). The next change is the development of neutrophilic leukocytosis (from 10 to 35 x 109/L) with a shift to the left. The hemoglobin and hematocrit do not fall immediately but fall as tissue fluids move into the blood circulation. It can be 48 or 72 hours after the hemorrhage until the full extent of the red cell loss is apparent. ACUTE BLOOD LOSS ANEMIA #4 Laboratory findings (cont.) Assuming that the patient with acute bleeding was healthy before the episode The peripheral blood film at 24 hours should be essentially normochromic and normocytic with normal red blood cell indices (MCV, MCH, and MCHC). An increased number of reticulocytes reach the circulating blood because of increased erythropoiesis and a transient macrocytosis develops. This phenomenon takes place beginning approximately 3 to 5 days after the blood loss and reaches a maximum approximately 10 days later. 4  6/28/2024 ACUTE BLOOD LOSS ANEMIA #5 Laboratory findings (cont.) It takes about 2 to 4 days after the blood loss for the total white blood cell count to return to normal. It takes about 2 weeks for the morphologic picture to disappear. The return of the red cell profile to previous values takes longer than 2 weeks. ACUTE BLOOD LOSS ANEMIA #6 5  6/28/2024 CHRONIC BLOOD LOSS ANEMIA #7 Etiology Chronic blood loss is frequently associated with disorders such as the following: Gastrointestinal (GI) tract Heavy menstruation in women Urinary tract abnormalities CHRONIC BLOOD LOSS ANEMIA #8 In chronic anemias, blood loss of small amounts occurs over an extended period, usually months. The chronic and continual loss of small volumes of blood does not disrupt the blood volume. If blood is lost in small amounts over an extended period Both the clinical and hematological features seen in acute bleeding are absent. Regeneration of red blood cells occurs at a slower rate. The reticulocyte count may be normal or only slightly increased. 6  6/28/2024 CHRONIC BLOOD LOSS ANEMIA #9 Laboratory findings A noticeable anemia does not usually develop until after storage iron is depleted. Gradually, the chronic bleeding results in an iron deficiency, and the newly formed cells are morphologically hypochromic and microcytic. The white blood cell count is normal or slightly decreased. Platelets are commonly increased, and only later, in severe iron deficiency, are they likely to be decreased. POSTAMBLE READ the TEXTBOOK for the details to answer the UNIT OBJECTIVES. USE THE UNIT OBJECTIVES AS A STUDY GUIDE All test questions come from detailed material found in the TEXTBOOK (Not this PowerPoint) and relate back to the Unit Objectives 7