Introduction:
Before any surgery, assessing the patient's bleeding risk is necessary, as it is a key component in the blood management strategies to reduce blood loss. Various reasons can put a patient at risk of bleeding, like old age, medications affecting hemostasis, decreased preoperative red blood cell volume, medical conditions causing hemostatic defects like hereditary bleeding disorders, and medical conditions that are acquired, such as liver and kidney disease, and the type of surgery.
Preoperative assessment includes a questionnaire, physical examination, and laboratory testing regarding the clinical bleeding history. If the preoperative tests suggest a positive bleeding history, the patient may be referred to a specialist for further assessment and management. Routine coagulation screening is not recommended in patients with no bleeding risk.
What Is Hemostasis?
Hemostasis is the body’s natural mechanism that helps stop bleeding from the injured blood vessels. It also helps in the repair of the injury. Hemostasis consists of many interlinked steps, which help form a plug that covers up the injured site of the blood vessel and controls the bleeding. In serious injuries, the capability of hemostasis is essential to keep a person alive. However, in some rare cases, the processes that control hemostasis may not function effectively, causing potentially dangerous problems with clotting or bleeding.
How Is a Preoperative Assessment of Hemostats Done?
For each patient, clinical history and physical examination, and the risk of bleeding from a particular surgical procedure, should be evaluated before advising a preoperative laboratory screening for bleeding disorders.
Clinical History: A detailed clinical history is very important to evaluate any medical condition; it is the same in the hemostasis assessment. The international guidelines recommend a structured patient questionnaire before surgery or invasive procedures to check for bleeding risk.
This questionnaire includes the following:
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Personal and family bleeding history.
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Previous excessive post-surgical bleeding or post-traumatic.
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History of any medical condition or disease which may increase bleeding risk, such as hepatic, renal, or hematologic disease.
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Complete information on the patient’s medication, including alternative medications.
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Develop large bruises even if there is no obvious injury.
Medication Assessment - Hemostasis will be affected by numerous medications and complementary therapies, so a complete patient history and a list of medications are required. The management of antiplatelet agents (medications that prevent the formation of blood clots), including Aspirin, non-steroidal anti-inflammatory agents, and Clopidogrel; and anticoagulant therapy (medications that prevent the formation of blood clots), including Heparin, Warfarin, and the new oral anticoagulants (NOAC) will need to be customized for each patient to reduce the risk of bleeding. While customizing the medication, the nature of the procedure, the indications for the medications, and its risk of bleeding should be considered. A group of healthcare providers may be needed to curate a patient's appropriate management plan, including surgeons, cardiologists, hematologists, anesthetists, clinical nurse consultants, pre-admission staff, and pharmacists.
Physical Examination - A physical examination is a must in evaluating bleeding disorders. It should be performed as a second step, mainly concentrating on signs of bleeding and diseases that may cause it. The following findings are suggestive of a potential bleeding disorder:
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The appearance of petechiae (small red or purple spot) or ecchymoses (small bruise) suggests a deficiency of platelets in the blood (thrombocytopenia).
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Telangiectasias (small, widened blood vessels on the skin) may occur due to underlying liver disease like cirrhosis or hereditary hemorrhagic telangiectasia.
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If the patient has a history of hemarthrosis (articular bleeding), such as joint deformities, and a bleeding history, it can be due to severe clotting factor deficiency.
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The presence of hematomas (pooling blood underneath the skin, appearing as bruises) may also be due to clotting factor deficiency.
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Hyperelasticity of the skin and hyperextensible joints may suggest collagen-vascular disorders like Ehlers-Danlos syndrome.
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Any evidence of bleeding or anemia, including location, size, and distribution of hematomas, ecchymoses, and petechiae, should be noted.
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Evidence of increased bleeding risks such as spider angioma, jaundice, splenomegaly, joint and skin laxity, arthropathy, and telangiectasia should also be assessed.
Laboratory Tests - If the clinical history and physical examination strongly suggest the presence of a bleeding disorder, then the surgeon will request a medical or hematologic consultation to check for the possibility of bleeding, mainly if the clinical history and physical examination strongly suggest a bleeding disorder. Further, the surgeon may suggest a few laboratory tests be performed, if the history and physical examination are not suggestive of a bleeding disorder, which includes:
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Complete blood count (CBC) with white blood cell differential and platelet count
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PT (prothrombin time) and aPTT (Activated Partial Thromboplastin ).
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Review of the peripheral blood smear.
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Thrombin time.
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Creatinine.
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Liver function studies.
What Are the Surgical Procedures That Carry Bleeding Risks?
Cardiovascular Surgery - Cardiovascular surgery is often associated with major blood loss, which can lead to loss of coagulation factors and red blood cells. In cardiac surgery patients, bleeding may be exacerbated by antithrombotic therapy (to dissolve blood clots), extracorporeal circulation, and volume replacement. If perioperative bleeding increases, failure to maintain hemostasis can increase the risk of re-exploration surgery, lengthy ICU (intensive care unit) stay transfusion requirements, morbidity, and mortality.
Gynecological Oncologic Surgery - Although all gynecologic surgery is not associated with a high bleeding risk, patients undergoing gynecologic oncology surgery may be at high risk. A study was carried out on 351 patients undergoing gynecologic oncology. Twelve patients had prolonged PT or aPTT, and 57 patients had an elevation of fibrinogen and positive D-dimer. And 188 reported at least one abnormal test result. No perioperative deaths or other risks were reported due to bleeding. Only one case of a postoperative hematoma was reported. This concluded that routine preoperative testing for bleeding was of little use clinically.
Prostate Surgery - Surgery for benign and malignant prostate disease is associated with an increased risk of bleeding as the urogenital system is rich in urokinase. Hence, it is crucial to undergo preoperative hematologic screening tests.
Conclusion:
Before every surgery, a complete screening for hemostasis is necessary to avoid unwanted mishaps. Different screening modes include clinical history, physical examination, and laboratory tests. Laboratory tests are often indicated for patients with bleeding disorders or a history of severe bleeding. If abnormalities are detected in any tests, they will be managed accordingly.
