Aim. The aim of this study was to evaluate the effect of using “Pain Assessment Tool” by nurses on analgesics requirement and patient’s satisfaction after coronary bypass graft surgery.

Background. One of the main duties of caregivers in ICU is relieving patients’ pain. Using "Pain Assessment Tool" may have a positive effect on the choice of analgesics and dosage adjustment with patients’ requirements. More research is still needed.

Method. In a clinical trial, 153 hospitalized patients in the intensive care unit were selected randomly and were divided into two experimental (n=77) and Control group (n=76). The Pain Assessment Tool and pain management for 48 hours were implemented for conscious patients. Routine measures were taken into account for control group and the severity of pain and analgesic injection for experimental group were determined. In both groups, the amount of analgesics administered for pain relief, and patient satisfaction were recorded. Data were analyzed by SPSS version 16.

Findings. The use of Pain Assessment Tool increased the number of recipients of analgesic drugs and reduced their dosage over 48 hours in the experimental group. Also, the satisfaction of pain relief was higher in the experimental group than the control group (p<0.0001).

Conclusion. The findings of this study demonstrate the positive effect of Pain Assessment Tool on pain control, proper use of analgesics, prescribing the proper dose of analgesics based on patients’ pain and satisfaction improvement. The measurement of pain severity using Pain Assessment Tool, before and after analgesics administration is suggested.