This article will discuss how to assess acute pain in critically ill patients.
Pain should be predicted in all patients, and every action should be questioned for its possibility of causing pain or discomfort. Anticipating pain allows alternative strategies to be considered or pre-emptive analgesics given (Mallet et al. 2013).
Pain is defined as ‘An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage’ (IASP 2020).
Between 40 and 77% of critically ill patients admitted to intensive care units are estimated to experience moderate to severe pain (Bhattacharyya et al. 2023).
Pain often occurs at rest and during standard care procedures, and can lead to adverse outcomes such as stress responses, cognitive impairment, impaired sleep and agitation (Seo et al. 2022).
Potential causes of pain in critically ill patients can include:
(Pandharipande & Hayhurst 2024; Seo et al. 2022; Devlin et al. 2018)
Pain is often underreported in critically ill patients (Pandharipande & Hayhurst 2024). Therefore, patients should be assessed for pain regularly, and the frequency of assessment should be patient-specific and adjusted according to their risk.
A qualitative study by Bhattacharyya et al. (2023) identified several potential barriers to adequate pain management in ICU settings, including:
Untreated pain can pose serious consequences for the already compromised critically ill patient, potentially leading to both short and long-term physical and psychological consequences such as:
(Bhattacharyya et al. 2023; Seo et al. 2022)
Careful consideration needs to be given to the assessment method chosen for critically ill patients because they are often unable to participate in the pain assessment process.
Below are some methods of assessing pain in critically ill patients:
Self-report is considered the most reliable method of pain assessment (Health.vic 2024)
This method is offered to patients who are able to communicate, even if not verbally. A numerical rating scale (NRS) with a standard scale of 0-10 (where 0 = pain-free and 10 = worst pain you can imagine) can still be used if the patient is able to point to the scale or nod at simple commands (Nordness et al. 2021).
Other examples of self-report assessment tools include the verbal description scale (VDS) and the visual analogical scale (VAS)
You may be unable to obtain a self-report from some critically ill patients due to factors such as sedation or delirium. In these cases, an observation of the patient’s pain behaviours can be used to measure pain instead (Chanques & Gélinas 2022).
The most reliable pain assessment tools for critically ill patients who cannot self-report are the behavioural pain scale (BPS) and the critical care observation pain tool (CPOT) (Seo et al. 2022).
| Facial expression | Relaxed | +1 |
| Partially tightened (e.g. brow lowering) | +2 | |
| Fully tightened (e.g. eyelid closing) | +3 | |
| Grimacing | +4 | |
| Upper limb movement | No movement | +1 |
| Partially bent | +2 | |
| Fully bent with finger flexion | +3 | |
| Permanently retracted | +4 | |
| Compliance with mechanical ventilation | Tolerating movement | +1 |
| Coughing, but tolerating ventilator for most of the time | +2 | |
| Fighting ventilator | +3 | |
| Unable to control ventilation | +4 |
(Adapted from Seo et al. 2022)
The scores from each of the three sections are added together:
| No pain | ≤ 3 |
| Mild pain | 4-5 |
| Unacceptable amount of pain | 6-11 |
| Maximum pain | ≥ 12 |
(Adapted from MDCalc n.d.)
Typically, a score of ≥6 indicates sedation and/or analgesia.
| Facial expression | No muscular tension observed | Relaxed, neutral | +0 |
| Presence of frowning, brow lowering, orbit tightening and levator contraction | Tense | +1 | |
| All of the above facial movements plus eyelid tightly closed | Grimacing | +2 | |
| Body movement | Does not move at all (does not necessarily mean absence of pain) | Absence of movements | +0 |
| Slow, cautious movements, touching or rubbing the pain site, seeking attention through movements | Protection | +1 | |
| Pulling tube, attempting to sit up, moving limbs/thrashing, not following commands, striking at staff, trying to climb out of bed | Restlessness | +2 | |
| Muscle tension: evaluating by passive flexion and extension of upper extremities | No resistance to passive movements | Relaxed | +0 |
| Resistance to passive movements | Tense, rigid | +1 | |
| Strong resistance to passive movement, inability to complete them | Very tense or rigid | +2 | |
| Compliance with the ventilator (intubated patients) OR | Alarms not activated, easy ventilation | Tolerating ventilator or movement | +0 |
| Alarms stop spontaneously | Coughing but tolerating | +1 | |
| Asynchrony: blocking ventilation, alarms frequently activated | Fighting ventilator | +2 | |
| Vocalisation (extubated patients) | Talking in normal tone or no sound | Talking in normal tone or no sound | +0 |
| Sighing, moaning | Sighing, moaning | +1 | |
| Crying out, sobbing | Crying out, sobbing | +2 |
(Adapted from Seo et al. 2022)
The total score of the CPOT will be between 0 and 8, where 0 ≤ 2 indicates no pain and > 2 indicates pain and the need for analgesia (Nazari et al. 2022).
Effective pain assessment is an important element of the nurses’ role. The effects of inadequate pain management are significant and can lead to delayed healing and prolonged recovery. The nurse, therefore, must be competent in pain assessment methods in order to identify pain in critically ill patients so that appropriate analgesia can be administered.
Question 1 of 3
What does a total score of > 2 on the Critical Care Observation Pain Tool (CPOT) indicate?
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