Measuring pain or discomfort during routine nursing care in lightly sedated mechanically ventilated intensive care patients: A prospective preliminary cohort study

Background

Pain is routinely measured on mechanically ventilated ICU patients. However, the tools used are not designed to discriminate between pain and non-pain discomfort, a distinction with therapeutic implications.

Objectives

To evaluate whether clinical measurement tools can discern both pain and non-pain discomfort.

Methods

A prospective observational cohort study was conducted in a General ICU at a tertiary Medical Center in Israel. The Behavior Pain Scale (BPS) and Visual Analog Scale (VAS) of Discomfort were simultaneously assessed by a researcher and bedside nurse on thirteen lightly sedated patients during 71 routine nursing interventions in lightly sedated, mechanically ventilated, adult patients. Patients were asked whether they were in pain due to these interventions.

Results

Statistically significant increases from baseline during interventions were observed [median change: 1.00 (-1–5), 1.5(-4–8.5), p < 0.001] as measured by BPS and VAS Discomfort Scale, respectively. BPS scores ranged between 4 and 6 when the majority (53 %) of the patients replied that they had no pain but were interpreted by the clinicians as discomfort. Endotracheal suctioning caused the greatest increase in BPS and VAS, with no statistically significant differences in BPS and VAS Discomfort Scale scores whether patients reported or did not report pain. A BPS>6 had a higher sensitivity and specificity to reported pain (accuracy of 76 %) compared to a BPS of 4–6.

Conclusions

Standard assessments are sensitive to pain caused by routine nursing care interventions. However, this study presents evidence that among lightly sedated ICU patients, moderate BPS scores could also measure non-pain discomfort. ICU nurses should be aware that signs of unpleasantness measured by a pain scale could reflect non-pain discomfort.