wifi_classification: Wound, Ischemia, and foot Infection (WIfI) Classification...

In cliot: Clinical Indices and Outcomes Tools

Wound, Ischemia, and foot Infection (WIfI) Classification System

Description

Calculates the WIfI classification stage to predict the 1-year risk of major amputation and the potential benefit of revascularization in patients with threatened lower limbs (chronic limb-threatening ischemia). The system integrates three key factors: Wound extent, Ischemia severity, and foot Infection severity.

Usage

wifi_classification(wound_grade, ischemia_grade, infection_grade)

Arguments

wound_grade	Numeric (0-3). 0: No ulcer/gangrene. 1: Small ulcer, no gangrene. 2: Deep ulcer or gangrene limited to digits. 3: Extensive ulcer or gangrene involving forefoot/midfoot.
ischemia_grade	Numeric (0-3). Based on ABI, Ankle Pressure (AP), or Toe Pressure (TP). 0: ABI >= 0.80, TP >= 60. 1: ABI 0.6-0.79, TP 40-59. 2: ABI 0.4-0.59, TP 30-39. 3: ABI <= 0.39, TP < 30.
infection_grade	Numeric (0-3). Based on IDSA/IWGDF criteria. 0: No infection. 1: Mild (local < 2cm cellulitis). 2: Moderate (> 2cm cellulitis or deep structures). 3: Severe (SIRS/Sepsis).

Value

A list containing:

WIfI_Stage	The calculated clinical stage (1-4).
Amputation_Risk_1_Year	Estimated risk of major amputation at 1 year (Very Low, Low, Moderate, High).
Revascularization_Benefit	Estimated benefit of revascularization.

References

Mills JL Sr, Conte MS, Armstrong DG, et al. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System: risk stratification based on wound, ischemia, and foot infection (WIfI). J Vasc Surg. 2014;59(1):220-34.e1-2. doi:10.1016/j.jvs.2013.08.003

Examples

# Example 1: High Risk
# Extensive gangrene (3), Severe Ischemia (3), Moderate Infection (2)
wifi_classification(3, 3, 2)

# Example 2: Low Risk
# Small ulcer (1), Mild Ischemia (1), No Infection (0)
wifi_classification(1, 1, 0)

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