apache_ii_score: APACHE II Score

In cliot: Clinical Indices and Outcomes Tools

APACHE II Score

Description

Calculates the Acute Physiology and Chronic Health Evaluation II (APACHE II) Score. This severity-of-disease classification system is used to estimate in-hospital mortality for adult patients admitted to the Intensive Care Unit (ICU). The score is calculated based on 12 physiological measurements, age, and chronic health status measured within the first 24 hours of ICU admission.

Usage

apache_ii_score(age, temperature_c, mean_arterial_pressure, heart_rate,
                respiratory_rate, fio2, pao2, paco2 = NULL, arterial_ph,
                sodium, potassium, creatinine, acute_renal_failure,
                hematocrit, wbc_count, gcs_total, chronic_organ_insufficiency,
                admission_type)

Arguments

age	Numeric. Patient age in years.
temperature_c	Numeric. Rectal temperature in degrees Celsius.
mean_arterial_pressure	Numeric. Mean Arterial Pressure (MAP) in mmHg.
heart_rate	Numeric. Heart rate in bpm.
respiratory_rate	Numeric. Respiratory rate in breaths/min.
fio2	Numeric. Fraction of Inspired Oxygen (0.21 - 1.0).
pao2	Numeric. Arterial partial pressure of oxygen (mmHg).
paco2	Numeric (Optional). Arterial partial pressure of carbon dioxide (mmHg). Required only if FiO2 >= 0.5 for A-a gradient calculation.
arterial_ph	Numeric. Arterial pH.
sodium	Numeric. Serum sodium in mEq/L.
potassium	Numeric. Serum potassium in mEq/L.
creatinine	Numeric. Serum creatinine in mg/dL.
acute_renal_failure	Numeric (0 or 1). Presence of Acute Renal Failure (Doubles the creatinine points). (1 = Yes, 0 = No).
hematocrit	Numeric. Hematocrit percentage (e.g., 40 for 40%).
wbc_count	Numeric. White Blood Cell count in x1000/mm3 (e.g., 10 for 10,000).
gcs_total	Numeric. Total Glasgow Coma Scale (3-15).
chronic_organ_insufficiency	Numeric (0 or 1). History of severe organ insufficiency (liver, CV, resp, renal) or immunocompromised state. (1 = Yes, 0 = No).
admission_type	String. Type of ICU admission. Options: "non_operative", "emergency_postop", "elective_postop".

Value

A list containing:

APACHE_II_Score	The calculated severity score (Range 0-71).
Est_Hospital_Mortality	Approximate mortality percentage based on Knaus et al. (1985).

References

Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE II: a severity of disease classification system. Crit Care Med. 1985;13(10):818-829.

Examples

# Example 1: Critical Patient (High Score)
# 75yo, Temp 39, MAP 50, HR 140, RR 35, PaO2 50 (FiO2 0.4), pH 7.2, Na 130, K 6.0,
# Cr 2.0 (ARF), Hct 25, WBC 25, GCS 10, Chronic organ failure (Non-op)
apache_ii_score(75, 39, 50, 140, 35, 0.4, 50, NULL, 7.2,
130, 6.0, 2.0, 1, 25, 25, 10, 1, "non_operative")

# Example 2: Stable Post-Op
# 50yo, Normal vitals/labs, GCS 15, No chronic health issues, Elective surgery
apache_ii_score(50, 37, 90, 80, 16, 0.21, 90, NULL,
7.4, 140, 4.0, 1.0, 0, 40, 8, 15, 0, "elective_postop")

cliot documentation built on Dec. 1, 2025, 1:06 a.m.