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Neonatal Facial Coding System for assessing postoperative pain in infants: item reduction is valid and feasible
Jeroen W B Peters1, Hans M Koot, Ruth E Grunau
1Department of Pediatric Surgery, Erasmus MC-Sophia, Rotterdam, The Netherlands. j.peters@erasmusmc.nl
Insights
The Neonatal Facial Coding System (NFCS) effectively assesses postoperative pain in infants. A reduced 5-item NFCS measure maintains validity and sensitivity for pain detection.
Area of Science:
- Pediatric Anesthesiology
- Pain Management
- Neonatal Care
Background:
- Accurate assessment of postoperative pain in neonates and infants is crucial for effective pain management.
- The Neonatal Facial Coding System (NFCS) is a tool used to evaluate pain in this population.
- Previous research has explored the utility of the NFCS, but its validity and potential for refinement require further investigation.
Purpose of the Study:
- To evaluate the validity of the Neonatal Facial Coding System (NFCS) for assessing postoperative pain in children aged 0-18 months.
- To explore the possibility of reducing the number of facial action items within the NFCS for improved pain assessment.
Main Methods:
- A prospective, observational study involving 37 children undergoing major abdominal or thoracic surgery.
- Outcome measures included the NFCS, COMFORT behavioral scale, Visual Analog Scale (VAS), heart rate, blood pressure, and plasma concentrations of catecholamines and morphine.
- NFCS coding, behavioral scores, VAS, vital signs, and plasma concentrations were recorded at 3-hour intervals for 24 hours postoperatively.
Main Results:
- The full 10-item NFCS index showed significant associations with COMFORT scores, VAS, heart rate, and blood pressure, but not with biochemical markers.
- Multidimensional scaling identified 5 key NFCS items (brow bulge, eye squeeze, nasolabial furrow, horizontal mouth stretch, taut tongue) for a reduced pain measure.
- This 5-item NFCS measure also demonstrated significant correlations with behavioral and physiological pain indicators.
Conclusions:
- The Neonatal Facial Coding System (NFCS) is a reliable, feasible, and valid tool for assessing postoperative pain in infants.
- Reducing the NFCS to 5 core items enhances specificity for pain assessment without compromising sensitivity or validity.
Objective:
The objectives of this study were to: (1). evaluate the validity of the Neonatal Facial Coding System (NFCS) for assessment of postoperative pain and (2). explore whether the number of NFCS facial actions could be reduced for assessing postoperative pain.
Design:
Prospective, observational study.
Patients:
Thirty-seven children (0-18 months old) undergoing major abdominal or thoracic surgery.
Outcome Measures:
The outcome measures were the NFCS, COMFORT "behavior" scale, and a Visual Analog Scale (VAS), as well as heart rate, blood pressure, and catecholamine and morphine plasma concentrations. At 3-hour intervals during the first 24 hours after surgery, nurses recorded the children's heart rates and blood pressures and assigned COMFORT "behavior" and VAS scores. Simultaneously we videotaped the children's faces for NFCS coding. Plasma concentrations of catecholamine, morphine, and its metabolite M6G were determined just after surgery, and at 6, 12, and 24 hours postoperatively.
Results:
All 10 NFCS items were combined into a single index of pain. This index was significantly associated with COMFORT "behavior" and VAS scores, and with heart rate and blood pressure, but not with catecholamine, morphine, or M6G plasma concentrations. Multidimensional scaling revealed that brow bulge, eye squeeze, nasolabial furrow, horizontal mouth stretch, and taut tongue could be combined into a reduced measure of pain. The remaining items were not interrelated. This reduced NFCS measure was also significantly associated with COMFORT "behavior" and VAS scores, and with heart rate and blood pressure, but not with the catecholamine, morphine, or M6G plasma concentrations.
Conclusion:
This study demonstrates that the NFCS is a reliable, feasible, and valid tool for assessing postoperative pain. The reduction of the NFCS to 5 items increases the specificity for pain assessment without reducing the sensitivity and validity for detecting changes in pain.
