Page 1238 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 90: Bleeding Disorders 845

TABLE 90-2 Categories and Criteria for Assessment of ICU Bleeding Severity 1
• Initial management approaches to thrombocytopenias vary con-
siderably and create the necessity for early recognition of distinct Fatal bleeding
disorders including heparin-induced thrombocytopenia, throm- Major bleeding
botic thrombocytopenic purpura, disseminated intravascular Increase in heart rate by 20 bpm or more
coagulation, and other common thrombocytopenias. Decrease in systolic BP by 10 mm Hg or more while patient sitting up
• Disorders of soluble coagulation factors are revealed by abnormal Spontaneous decrease in systolic BP of 20 mm Hg or more
Decrease in hemoglobin of 20 g/L or more
results in the prothrombin time, activated partial thromboplastin Bleeding into critical sites:
time, and other tests including thromboelastography. Intracranial
• Factor deficiencies, factor inhibitors, von Willebrand disease, and Pericardial
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other complex coagulopathies including disseminated intravas- Intraspinal
cular coagulation, HELLP syndrome, massive transfusion, and Intraarticular (nontraumatic)
anticoagulant-related syndromes have specific therapies to reduce Intraocular (not subconjunctival)
the rate and risk of bleeding. Retroperitoneal
• There are specific indications and appropriate applications for Transfusion of two or more units of RBCs with no increase in hemoglobin concentration
platelet transfusion, cryoprecipitate, fresh frozen plasma, concen- Wound-related bleeding requiring an intervention
trated and activated factors, as well as other medications, including Minor bleeding—bleeding that did not meet criteria for fatal or major bleeding
inhibitors of fibrinolysis. Data from Arnold DM, Donahoe L, Clarke FJ, et al. Bleeding during critical illness: a prospective cohort
study using a new measurement tool. Clin Invest Med. 2007;30(2):E93-E102.

INTRODUCTION ICU-based definitions of bleeding primarily rely on a dichotomy of
major or minor bleeding. A practical approach is to define major bleed-
Coagulation disorders and complications of bleeding are common and ing as causing hypovolemic shock, affecting critical sites, requiring an
require proactive assessment and management. Intensive monitoring of invasive intervention, leading to transfusion of at least two units of red
ICU patients demonstrates that a substantial majority will have either a blood cells, or causing otherwise unexplained hypotension or tachycar-
coagulation defect or bleeding. Furthermore, the coagulation abnormal- dia. Improved reliability of bleeding assessment results when assessment
5
ities convey important prognostic information and a substantial number is reflective of the amount of blood loss, the rate of blood loss, and the
of patients will have severe, major bleeding. Because of the particularly physiologic consequence of bleeding. More specific criteria for major
1,2
6
high prevalence and significant impact of bleeding disorders in critically and minor bleeding that have high levels of interobserver reliability
ill patients, effective and efficient ICU care requires timely recognition include localized anatomic criteria as well as numeric laboratory and
and mitigation of disorders of platelets, soluble coagulation factors, physiologic criteria that correlate with volume of blood loss (Table 90-2). 1
and vascular lesions. Appropriate management of bleeding disorders
depends on recognition and adherence to specific treatment guidelines FREQUENCY AND GENERAL RISK FACTORS
for a wide variety of patients such as those with massive transfusion and
trauma, disseminated intravascular coagulation, thrombotic thrombo- FOR BLEEDING IN ICU PATIENTS
cytopenic purpura, and anticoagulant-related hemorrhage. The risk of bleeding depends on patient and disease factors as well as
specific hematologic parameters including vascular integrity, platelets and
CLINICAL ASSESSMENT OF BLEEDING clotting factor concentrations and function. Furthermore, the reported
IN CRITICALLY ILL PATIENTS frequency of bleeding is directly related to ascertainment issues such as the
clinical definition of bleeding as well as the frequency and thoroughness of
Reliable monitoring and reporting of bleeding in critically ill patients bleeding assessment. Reliable, detailed, and sensitive assessments for bleed-
is essential for accurate safety and performance assessments. Careful ing are typically used for therapeutic monitoring of bleeding complications
assessment of the risk and impact of hemorrhage is also critical for in therapeutic trials involving hemostatic or anticoagulant medications.
the appropriate selection of evidence-based treatments. However, the When such detailed and focused clinical bleeding evaluations were applied
standards for monitoring, assessment, and treatment of ICU bleeding to a general, adult, medical-surgical ICU population of 100 consecutive
are highly variable. Furthermore, clinical studies utilizing bleeding patients, 90 patients were found to have had 480 discrete bleeding episodes
assessment scales are usually constrained by application in homogenous, over an average ICU length of stay of 5 days. Of these events, 95% were
single-disease patients. The World Health Organization (WHO) took minor but 5% were classified as major. Risk factors for bleeding in this
3
an early initiative to sponsor and develop standard grading scales for cohort were thrombocytopenia and prolonged coagulation times, but not
reporting complications of cancer treatment including bleeding. While renal failure or receipt of pharmacologic thromboprophylaxis. 1
4
the WHO scale (Table 90-1) is one of the most commonly reported Using less-specific criteria, a wide range of bleeding frequencies
scales, the routine use of this grading system is limited in its application and risk factors have been described in general, critically ill popula-
in general ICU patients because it is not specifically linked to anatomic, tions. Rates of bleeding as the cause of initial admission to an ICU are
physiologic, and therapeutic response. highly variable and depend on the medical, surgical, neurosurgical, and
trauma designation of patients served by the unit. Based on descriptions
of major bleeding or clinically significant bleeding, 5% to 15% of all
TABLE 90-1 World Health Organization Standard Scale for Reporting Bleeding
ICU patients develop some form of bleeding after admission that has
Grade Criteria practical, clinical relevance. For example, a single-center prospective
observation of 1328 patients admitted to a mixed medical-surgical ICU
0 No bleeding
described 29% of patients as having bleeding present on admission,
1 Petechiae plus an additional 10% developed clinical bleeding after admission. The
2 Mild blood loss most common site of bleeding was gastrointestinal and the risk factors
3 Gross blood loss for bleeding were mechanical ventilation, malnutrition, renal failure,
7
anticoagulant use, and antiulcer medications. As expected, the rate of
4 Debilitating blood loss
clinically significant or major bleeding in all adult patients is lower than

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