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1. Bleeding Disorders
Bleeding disorders due to hematological causes can manifest as
- bleeding into skin or mucous membranes and can be associated with immediate type of bleeding, i.e., at the time of surgery and immediately post op., particularly beyond 24 hours post op. or
- bleeding into deep tissues and joints resulting in delayed type of bleeding, that typically occurs 4–10 days postoperatively.
Spontaneous bleeding with minor trauma and bleeding in several sites is suggestive of a general bleeding disorder
1.1. Immediate Type of Bleeding
Seen as an ooze that continues beyond 24 hours postoperatively. It is normal to see bleeding for 12-18 hours post op. This type of bleeding disorder is associated with bleeding into skin and mucous membranes and results in small pinpoint hemorrhagic lesions (called petechiae), and small dime sized bruises (called ecchymosis).
When injury occurs, platelets immediately plug the injured area and, by adhering to each other, contribute toward cessation of bleeding and clot formation. The following factors may precipitate the immediate type of bleeding in the patient.
- Reduction in platelet number (thrombocytopenia). You will see reduced PLATELET count and increased BT (bleeding time) on lab testing.
- Platelet dysfunction. You will see normal PLATELET count and increased BT on lab testing.
- Drugs such as Aspirin and NSAIDs will demonstrate normal PLATELET and increased BT.
Note: Aspirin, if taken daily for extended periods, can affect the cohesiveness of the platelets. The effect lasts for the entire life span of the platelets (which is 10-14 days). Aspirin-affected platelets have to clear the circulation before surgical treatment can proceed. Routinely, aspirin is stopped seven days prior to a major surgical procedure. NSAIDs affect only the surface of the platelets. Effect on the platelets is temporary. Platelets regain their cohesiveness once the drug has been cleared completely. So with NSAIDs, surgical treatment can proceed on the day after the NSAID has been stopped.
When questioning a patient about platelet problems or vascular fragility, always question the patient about aspirin, corticosteroids, and nonsteroidal anti-inflammatory drugs (NSAIDs), especially when a patient is giving a positive bleeding history. Ask the patient if he/she bruises easily. If the response is “yes,” find out if this has always been the case or if the easy bruising has been a recent change. The latter is very significant. Another question to ask is “When you cut yourself, do you tend to bleed for a long time?” If “yes,” establish if this is a recent finding.
- Vascular fragility. We see a normal PLATELET count and BT. Chronic corticosteroid therapy is the leading cause of vascular fragility. Vitamin C deficiency—not often seen today—was an important etiological factor many years ago. Chronic steroid intake causes thinning of the connective tissue layer of the blood vessels.
- Von Willebrand’s Disease. You will see a normal PLATELET count and increased BT. (Described below.)
1.2. Delayed Type Bleeding
This type of bleeding is usually seen four to ten days postoperative as deep tissue bleeding. Bleeding into muscles (hematomas), joints (hemarthrosis), and large lime or orange sized bruises or ecchymosis occurs. Clotting factor deficiency, chronic liver disease (liver failure/cirrhosis), and the blood thinners heparin and coumadin are some of the common precipitating factors of delayed type bleeding. There is no abnormal bleeding during surgery, but 48 to 72 hours later the patient starts bleeding. PT/INR and PTT are tests used to access the patient’s capacity to clot adequately.
- Clotting factor deficiency.Hemophilia A (deficiency of factor VIII) and B (deficiency of factor IX) patients will be symptomatic from childhood. The other etiological factors usually cause symptoms later on in life. In hemophilia A and B, only men are affected. Females are potential carriers only. Both disorders affect clotting factors of the intrinsic clotting pathway and, therefore, prolong the PTT/APTT.
- Cirrhosis of the liver. Alcoholic liver cirrhosis or cirrhosis of the liver due to other causes, is the most common cause of delayed type bleeding. All clotting factors are manufactured in the liver with the exception of factor VIII. Chronic parenchymal liver disease( Cirrhosis) is commonly associated with bleeding tendency. Since all clotting factors but VIII are produced in the liver, both the intrinsic and extrinsic clotting pathways are affected and the PT/INR and PTT/APTT are both prolonged. The clotting factors have to drop below 50% of normal before you see the changes in these blood tests.
- Chronic small intestinal problems. These include Crohn’s and Coeliac disease. Chronic intestinal problems can cause decreased vitamin K absorption and lead to deficiency of factors II, VII, IX and X and consequent bleeding tendency. A lack of vitamin K leads to clotting factor deficiencies affecting both the intrinsic and extrinsic pathways and leads to prolonged PT/INR and PTT/APTT.
- Von Willebrand’s disease. (Described below.)
1.3. Von Willebrand’s Disease
This congenital condition runs in families and affects both men and women. It is associated with a deficiency of the Von Willebrand’s Factor(VWF). The VWF promotes platelet cohesiveness and transports factor VIIIc in the circulation. These patients can have both immediate and delayed types of bleeding when the deficiency is profound and causing the factor VIIIc levels to be below 50% of normal.. The most common complaint, however, is oozing at the time of surgery. This disease results in a prolonged BT and/or PTT.