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Ethics is a moral code of what we believe to be universally accepted principles of rightness and wrongness that influences our medical decisions. Ever-advancing technology and therapies constantly challenge and call into question previously established ethical norms. The most accessible approach is committing to the following principles: respect for autonomy, beneficence, nonmaleficence, and justice.1 These principles are dependent on a thorough understanding of the patient’s illness and how medical interventions, or the lack of will, impact his quality of life. What to advise may not be so easy and often the progress of the clinical course and morbidity and predictive scores are used to give the physician, patient, and family the global perspective into his illness.


These scores help benchmark the quality of care and aide with triage of patients who would benefit from care in the intensive care unit. They are also helpful with prognostication and guide the physician’s goals of care discussion with the patient or family members, particularly when the clinical course is equivocal.


In 1985, The Acute Physiology and Chronic Health Evaluation (APACHE) II is a scoring classification of disease severity using acute physiologic score (APS) based on 12 physiologic measurements, age, and chronic health points.2,3 APACHE II score of less than 25 points has less than or equal to 50% mortality with more than or equal to 35 points had 80% mortality.3 Criticism to APACHE II is that it provided information regarding severity of illness of patient groups but not individual patients.2,4 In 1991, the APACHE III revision provided risk stratification of individual patients within defined patient groups and the APACHE III Score and reference data on disease categories and treatment location allowed risk estimate for hospital mortality.5 There was a greater emphasis on the impact of the APS and the APACHE III Score range from 0-299. Along with Simplified Acute Physiology Score (SAPS) II and Mortality Probability Model (MPM) II, APACHE III was believed to have significantly different predicted mortality from observed.6-8 In 2006, APACHE IV (Score 0-252) remodeled the physiologic variables and weights and included 4 new predictor variables: (1) presence of mechanical ventilation; (2) use to thrombolytic therapy for acute myocardial infarction; (3) adjustments for prognostic implications of Glasgow Coma Scale (GCS) and Pao2 and Fio2; and (4) inability to assess GCS due to sedation or paralysis.8 APACHE IV has excellent discrimination with an area under a receive operating characteristic curve (AU-ROC) of 0.88. AU-ROC more than 0.80 indications good discrimination.8 Observed and mean predicted mortality were 13.5% and 13.55% (p = 0.76)8 (Table 36-1).

TABLE 36-1APACHE IV Variables: Data Items Collected and Used for Predicting Hospital Mortality Among Patients Admitted to Intensive Care Unit (ICU) ...

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