Objectives: Criteria for discharge after outpatient surgery do not take into consideration the patients’ assessment of discharge readiness. Our aim was to compare discharge readiness as determined by nurses with that determined by patients against the modified Aldrete score as a benchmark.

Design and setting: In this prospective study, a single observer followed 194 outpatients in the PACU. Modified Aldrete score was assigned and further assessments were made at 15-min intervals in parallel with those made by nursing staff. Nurses and patients were blinded to each others' assessments. Discharge readiness was quantified according to three different approaches:

1) time to reach a modified Aldrete score of >9,
2) time to discharge readiness according to the patient’s own evaluation and,
3) time to discharge readiness according to nursing assessments.

Results: All three times were significantly different from each other:
a) Time to achieve a modified Aldrete score >9 was 8.3+7.6 min,
b) Time the patient felt discharge ready was 45.3+39.5 min, c) Time the patient was actually discharged by nurses was 86.8+45.8 min.

Conclusions: Nursing staff tend to keep patients an additional 1.5 + 36.6 min in the PACU compared to the patients’ own evaluation. Significant cost saving could be potentially realised if outpatients who achieve a modified Aldrete score >9 are allowed some freedom in the determination of their own discharge readiness.