E-PASS Score Calculator | GastroChennai

E-PASS Calculator

Section A — Pre-operative Risk Score (PRS)

Chronic Heart Failure (cHF)

Chronic Lung Disease (cLD)

Diabetes Mellitus (cDM)

Performance Status (cIMC)

ASA Physical Status

Section B — Surgical Stress Score (SSS)

Blood Loss (mL)

Patient Weight (kg)

Blood Loss / kg Ratio

Operative Time

Incision Extent

E-PASS Formula

PRS = 0.001 × (−28.086 + 17.316×cHF + 17.316×cLD + 17.316×cDM + 17.316×cIMC + 17.316×ASA) SSS = 0.001 × (−0.342 + 0.357×BL_cat + 0.368×time_cat + 0.322×incision_cat) Where BL_cat: <100 mL/kg=0, 100–200 mL/kg=1, >200 mL/kg=2 Morbidity = e^(−1.402 + 2.073×PRS + 1.005×SSS) / [1 + e^(−1.402 + 2.073×PRS + 1.005×SSS)] Mortality = e^(−4.426 + 4.208×PRS + 1.905×SSS) / [1 + e^(−4.426 + 4.208×PRS + 1.905×SSS)]

PRS and SSS are intermediate scores with no direct clinical interpretation; only the derived morbidity and mortality probabilities are reported.

PRS Variables

Variable	0 pts	1 pt	2 pts
Chronic heart failure	None	NYHA I–II	NYHA III–IV
Chronic lung disease	None	Mild (FEV1 70–80%)	Severe (FEV1 <70% or home O2)
Diabetes mellitus	None	Diet / OHA	Insulin-dependent
Performance status	Normal	Limited demanding activity	Confined >50% waking hours
ASA	ASA I	ASA II	ASA III (2) / IV (3)

SSS Variables

Variable	0 pts	1 pt	2 pts
Blood loss / weight	<100 mL/kg	100–200 mL/kg	>200 mL/kg
Operative time	<2.5 h	2.5–5 h	>5 h
Incision extent	Laparoscopic	Open limited	Open extended

Interpretation

Morbidity %	Risk	Recommendation
<20%	Low	Standard peri-operative care
20–40%	Moderate	HDU; senior anaesthetist; pre-operative optimisation
>40%	High	ICU; consider less invasive alternatives; detailed consent

Clinical Application

E-PASS was validated in 417 elective gastrointestinal surgery patients (Haga 2004, World J Surg)
PRS quantifies fixed patient risk; SSS quantifies modifiable surgical stress — surgeons can reduce SSS by choosing laparoscopic or shorter operations where oncologically equivalent
Useful for matching operative approach to patient risk: high PRS = minimise SSS by choosing minimal access surgery
PRS can be calculated pre-operatively; SSS is retrospectively applied after the operation for quality reporting purposes
E-PASS is widely used in Japanese surgical quality programmes and GI surgery audits

References

Haga Y, et al. Estimation of physiologic ability and surgical stress (E-PASS) as a new prediction scoring system for postoperative morbidity and mortality following elective gastrointestinal surgery. Surg Today. 2004;34(3):208–214.
Haga Y, et al. Assessment of the estimation of physiologic ability and surgical stress score as a predictor of postoperative surgical outcome. J Gastrointest Surg. 2012;16(3):486–492.

E-PASS Score