How to Assess Pain

Pain is the most common reason patients seek healthcare, yet it remains one of the most challenging symptoms to assess objectively. Known as the “Fifth Vital Sign,” pain is a complex, subjective experience influenced by physiological, psychological, and cultural factors. Accurate assessment is the foundation of effective management. For nursing students, mastering the variety of pain scales and the nuance of assessment techniques is critical for patient advocacy and ethical practice. This guide details the protocols for rigorous pain evaluation.

Pain: The Subjective Reality

Margo McCaffery’s definition (1968) remains the clinical standard: “Pain is whatever the experiencing person says it is, existing whenever he says it does.” This mandates that the patient’s self-report is the primary source of assessment data.

The Joint Commission requires hospitals to screen all patients for pain and to document assessment and reassessment. Failure to assess pain is considered negligence.

Selecting the Right Pain Scale

Using the wrong scale invalidates the assessment. Selection depends on age, cognitive ability, and consciousness.

1. Numeric Rating Scale (NRS)

Population: Adults and children (>8 years) who are cognitively intact.
Method: “Rate your pain from 0 (No pain) to 10 (Worst possible pain).”
Pros/Cons: Quick and widely understood, but requires abstract thinking.

2. Wong-Baker FACES Scale

Population: Children (3+ years) and adults with mild cognitive impairment or language barriers.
Method: Patient points to the face that best represents their pain (from smiling to crying).
Caution: Do not use for unconscious patients; do not match the patient’s face to the drawing (they may be stoic).

3. FLACC Scale (Behavioral)

Population: Infants (2 months to 7 years) and non-verbal/unconscious patients.
Components:

• Face (Grimace)
• Legs (Restless/Kicking)
• Activity (Arched/Rigid)
• Cry (Moan/Scream)
• Consolability (Content/Difficult to console)

Each category is scored 0-2 for a total of 10.

4. CPOT (Critical Care Pain Observation Tool)

Population: Intubated or sedated ICU patients.
Method: Evaluates facial expression, body movements, muscle tension, and compliance with the ventilator.

Comprehensive Assessment: PQRST

A number (e.g., “7/10”) is not enough. You must gather the full narrative using the PQRST mnemonic.

• P – Provocation/Palliation: What makes it worse? (Movement, eating). What makes it better? (Rest, ice, meds).
• Q – Quality: Describe the sensation. (Sharp, dull, burning, stabbing, throbbing). Neuropathic pain is often “burning/electric,” while visceral pain is “cramping/achy.”
• R – Region/Radiation: Where is it? Does it travel? (e.g., Chest pain radiating to the left arm).
• S – Severity: The pain score (0-10).
• T – Timing: Onset (When did it start?), Duration (How long?), Frequency (Constant or intermittent?).

Physiological Indicators (Acute vs. Chronic)

The body adapts to pain over time.

Acute Pain (Sympathetic Response)

Triggers “Fight or Flight.” Look for:
Tachycardia, Hypertension, Tachypnea, Dilated pupils, Diaphoresis.

Chronic Pain (Adaptation)

The body adapts (Parasympathetic response). Vital signs may be normal even if the patient reports severe pain (10/10). Do not judge a patient’s pain report based on a lack of visible distress or normal vitals.

For assignments on the physiology of pain pathways, see our Pathophysiology Guide.

The Reassessment Cycle

Administering medication is only half the job. You must evaluate efficacy.

• IV Meds: Reassess in 15-30 minutes.
• Oral Meds: Reassess in 45-60 minutes.
• Documentation: Record the new pain score and any adverse effects (sedation, respiratory depression).

Review pharmacokinetics in our Pharmacology Study Guide to understand onset and peak times.

Barriers to Assessment

• Patient Barriers: Fear of addiction, desire to be a “good patient,” belief that pain is inevitable.
• Nurse Barriers: Personal bias (“drug seeking”), lack of time, over-reliance on vitals.

FAQs on Pain Assessment

Conclusion

Effective pain assessment moves beyond checking a box. It requires selecting the right tool, listening to the patient’s narrative, and understanding the physiology of suffering. By mastering these skills, nurses fulfill their ethical duty to alleviate pain and advocate for patient comfort.