Risk
Type of procedure
Examples
Low
Non-vital organs involved, exposed surgical site, limited dissection
Lymph node biopsy, dental extraction, cataract extraction, most cutaneous surgery, laparoscopic procedures, coronary angiography
Moderate
Vital organs involved, deep or extensive dissection
Laparotomy, thoracotomy, mastectomy, major orthopedic surgery, pacemaker insertion
High
Bleeding likely to compromise surgical result, bleeding complications frequent
Neurosurgery, ophthalmic surgery, cardiopulmonary bypass, prostatectomy, bladder surgery, major vascular surgery, renal biopsy, bowel polypectomy
History and Physical
A hemostatic history should be obtained on all patients regardless of the procedure being performed [1–4]. Patients should be asked about:
Personal history of abnormal bleeding, blood transfusion, easy bruising, and excessive bleeding associated with child birth, menses, minor trauma, or surgery (including dental procedures or tonsillectomy)
Family history of bleeding disorders
Past medical history of hepatic, renal, or hematologic disease
Current medication use, including aspirin, over-the-counter pain medications, antiplatelet medications, or anticoagulants, and vitamins, supplements, or herbal preparations
Physical exam may:
Suggest the presence of a hemostatic disorder (e.g. petechiae, purpura, ecchymoses)
Demonstrate chronic findings of hemostatic disorders (e.g., joint deformity and muscle atrophy in hemophiliacs)
Reveal signs of chronic conditions that result in hemostatic abnormalities (e.g., jaundice, ascites, and spider telangiectasias in cirrhosis, or pallor, lymphadenopathy, and splenomegaly in hematologic disease)
Testing
Routine preoperative laboratory testing, including platelet count, prothrombin time (PT/INR), and partial thromboplastin time (PTT), is generally not indicated for patients without a positive bleeding history [5–11]. Testing should be performed as indicated by the history and the procedural bleeding risk:
For low-risk procedures, if the history is reassuring for normal hemostasis, no further testing is required.
For high-risk procedures, and to a lesser degree for moderate-risk procedures, a platelet count, PT/INR, and PTT may be considered in addition to history [3].
For any procedure, initial testing for patients with a suspected disorder of hemostasis should include a platelet count, PT/INR, and PTT.
Perioperative Management
Thrombocytopenia
Thrombocytopenia (platelet count <150,000/μL) may be due to decreased production (e.g. medications, chemotherapy, hematologic disease, viral infection), splenic sequestration (e.g. liver disease), or increased destruction (e.g. immune thrombocytopenia, systemic lupus erythematosus).
Platelet counts may also be falsely low due to platelet clumping caused by EDTA in blood collection tubes (pseudothrombocytopenia).
Postoperative thrombocytopenia and heparin-induced thrombocytopenia (HIT) are discussed in Chaps. 20 and 21.
Unexplained thrombocytopenia should be evaluated prior to elective surgery. The initial evaluation should include a complete history and physical examination, a repeat CBC, and a peripheral blood smear. Additional testing will depend on the history and physical examination.
Both elective and emergent surgical procedures can be safely performed for most patients with thrombocytopenia or platelet dysfunction with the use of platelet transfusions. Recommendations for platelet transfusion for the surgical patient are listed in Table 19.2.
Plts <50,000/μL—platelet transfusion is indicated for the surgical patient
Plts 50,000–100,000/μL—considered adequate for most procedures, except for central nervous system (CNS) procedures for which platelet transfusion is indicated for platelet count <100,000/μL
Plts >100,000/μL—platelet transfusion is usually not necessary, but may be indicated if there is known or suspected platelet dysfunction or there is ongoing or anticipated bleeding
Effect of Platelet Transfusions
Platelet transfusions are either pooled (random donor) platelets or apheresis (single donor) platelets.
A unit of pooled platelets (50–60 mL) is prepared from platelets that have been separated from a unit of whole blood. Five or six units of pooled platelets from separate donors are usually combined into a single bag for transfusion, called a “five-” or “six-pack.”
A unit of apheresis platelets (150–300 mL) is collected from a single donor.
The effect of platelet transfusions is variable, but 4–6 units of pooled platelets or a single unit of apheresis platelets is expected to increase the platelet count by 30–60,000/μL in an average-sized patient.
A posttransfusion platelet count can be sent 10–60 min after transfusion to assess for response. The platelet count will gradually fall to pre-transfusion levels after 2–3 days.
If a patient does not respond to platelet transfusions, a pre- and posttransfusion platelet count should be obtained.
A patient is refractory to platelet transfusions if the platelet count fails to increase by 10,000/μL. The next step is to send panel reactive antibody (PRA) to test for the presence of HLA antibodies. If the patient has a high or a positive PRA, apheresis platelets should be collected from an HLA-matched donor for transfusion.
Immune Thrombocytopenia
Immune thrombocytopenia (ITP) is characterized by platelet destruction from platelet autoantibodies.
The prevalence of ITP in adults is estimated to be 9.5–23.6 per 100,000 persons [12].
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
