Background: There is currently no validated instrument for measuring workload in the post- anesthesia care unit (PACU). The aim was to investigate the inter-rater reliability of a workload instrument developed specifically for PACUs.

Method: Double, paired observations (n = 40) were performed by 13 critical care registered nurses (CCRN) on one PACU in southern Sweden. Inter-rater reliability was measured using Cohen's kappa coefficient.

Results: Of 11 workload domains, good/excellent agreement was observed in eight, fair agreement in two, and poor agreement in one. Clarifications of the instrument were performed.  

Conclusion: Workload measurement must be a repeating process involving renewal of the instrument as the care changes while nursing interventions can be improved by outcomes from workload measurements. This study can form the basis for the development of an evidence-based Post-Anesthesia Workload Instrument (PAWI) and is a multi-domain, objective tool for PACU workload measurement.