Applicability of scales/indicators for pain monitoring in critically ill patients incapable of verbalizing: a systematic review of the literature

Objective: To conduct a systematic review of the existing literature about the applicability of scales/indicators for pain monitoring in critically ill patients who are unable to verbalize. Methods: We performed a systematic review of the literature, according to the Joanna Briggs Institute's guidelines, in the following databases: MEDLINE, CINAHL, and Cochrane Central Register of Controlled Trials. The search was executed using, as main descriptors, "Critically Ill Patient", "Pain", "Scale" and "Instrument", in Portuguese, English, Italian, and Spanish. We considered the period between January 2012 and December 2017, and obtained a total of 149 results. From these, we selected 11 fi nal full-text articles for extraction and analysis, which met the required inclusion criteria. Two researchers made the search and two independent reviewers carried out the critical evaluation, extraction and synthesis of the data. Results: The key to adequate pain management lies in detecting and assessing several indicators, such as: facial expression, vocalization, body movements, muscle tone, adaptation to mechanical ventilation. Subsequently, it is fundamental to intervene accordingly and to reassess the patient's status. The BPS (Behavioral Pain Scale) and the CPOT (Critical-care Pain Observation Tool) are considered the most appropriate scales for pain assessment in critically ill patients who are incapable of verbalizing. While the BPS should only be used in ventilated patients, the CPOT can be used in both ventilated and non-ventilated patients. Conclusion: The BPS and the CPOT are two scales recognized as reliable, valid, and easy to apply, for pain monitoring in critically ill patients who are unable to verbalize their pain.