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Surgical Apgar Score

Intraoperative Risk Score for Major Postoperative Complications

The Surgical Apgar Score (SAS), developed by Gawande et al. (2007), uses three readily available intraoperative measurements — estimated blood loss, lowest mean arterial pressure, and lowest heart rate — to predict 30-day major complications and death.

Surgical RiskIntraoperativeGeneral Surgery
Surgical Apgar Score Calculator
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Surgical Apgar Score / 10

Scoring Criteria

Variable0 pts1 pt2 pts3 pts4 pts
EBL (mL)≥ 1000601–999101–600≤ 100—
Lowest MAP (mmHg)< 4040–5455–69≥ 70—
Lowest HR (bpm)> 85 or arrhythmia76–8566–7556–65≤ 55

Interpretation

SAS30-Day Major Complication / Death Rate
9–10~4%
7–8~16%
5–6~36%
0–4~75%

Major complications include return to OR, MI, PE, unplanned ICU admission ≥ 48h, DVT, pneumonia, sepsis, renal failure, and 30-day mortality.

Clinical Application

  • Timing: Calculate immediately at the end of surgery using data from the anaesthetic chart. The score is available before the patient leaves the OR.
  • SAS 0–4: Alert surgical and anaesthetic teams; proactive postoperative monitoring in ICU or HDU; early family notification of high-risk status.
  • SAS 5–6: Moderate risk; consider HDU; enhanced nursing observations for at least 24 hours; fluid balance monitoring.
  • SAS 7–10: Lower complication rates; standard postoperative ward care appropriate for most patients.
  • The SAS is complementary to preoperative scores (ASA grade, Charlson CCI). A preoperatively fit patient with a low intraoperative SAS has higher postoperative risk than their baseline status would predict.
  • Validated in colorectal, general surgery, and vascular surgery populations. Original derivation was in a US academic centre — confirm local complication rates in your context.
  • HR scoring note: The lowest HR scores highest (≤55 bpm = 4 pts) because bradycardia during surgery is a sign of good haemodynamic tolerance. An inappropriately high HR or arrhythmia during surgery scores 0 points regardless of the exact rate.

References

  1. Gawande AA, et al. The Surgical Apgar Score: an intraoperative grading system with power to predict postoperative morbidity and mortality. J Am Coll Surg. 2007;204(2):201–208.
  2. Reynolds PQ, et al. Multi-centre validation of the Surgical Apgar Score. J Am Coll Surg. 2010;210(5):745–756.

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Charlson CCI Caprini VTE Risk APACHE II