Pain perception description after advanced surface ablation

Abstract

Purpose: The objective of this study was to characterize the evolution of ocular pain after advanced surface ablation (ASA) to improve strategies in postoperative pain management.

Methods: This was a multicenter, prospective, descriptive, cohort study. The inclusion criteria were healthy individuals ≥18 years old receiving bilateral alcohol-assisted surface ablation with epithelial removal. Pain intensity was evaluated with the visual analog scale (VAS) and the numeric pain rating scale before and after surgery. Comorbidities (photophobia, burning, tearing, and foreign body sensation) and Hospital Anxiety and Depression (HAD) questionnaire were evaluated before and at 6 hours after surgery. Postoperative treatments included cold patch, topical cold antibiotics, topical steroids, and benzodiazepines.

Results: Thirty-two consecutive patients having similar profiles of postoperative pain evolution were included. At 0.5 hour after ASA, the pain score by VAS was 37±20 mm, and the maximum pain, 61±31 mm, occurred at 24 hours. Afterward, it decreased progressively until 72 hours after surgery (19±20 mm). Most patients (81%) scored >60 mm, and 44% required rescue medication. Among the comorbidities, all patients had photophobia and 84% had burning sensation. At 6 hours, the HAD score was 5.4±3.9, within the range of values considered as normal.

Conclusion: Postoperative acute ocular pain after ASA showed a characteristic evolution over time. Recognition of the pattern could be important for improving the acceptance of ASA and for improving strategies in pain management in the postoperative period.

Keywords: advanced surface ablation; model acute surgical pain; ocular pain.

Figure 1

Mean postoperative pain intensity development measured by VAS (blue line) and NPRS (orange line) questionnaires. Abbreviations: VAS, visual analog scale; NPRS, numeric pain rating scale.

Figure 2

Postoperative pain intensity evolution by gender. Notes: Females, black line; males, gray line. Abbreviation: VAS, visual analog scale.

Figure 3

Postoperative pain intensity evolution by age. Notes: >30 years old, black line; ≥25–30 years old, dark gray line; <25 years old, light gray line. Abbreviation: VAS, visual analog scale.

Figure 4

Overall pain level as estimated by PCA1. Notes: (A) PCA1 accounted for 77.9% of the total pain variability. Mean postoperative pain evolution, black line; mean value +2 standard deviations, red line; mean value -2 standard deviations, blue line. (B) Extreme PCA1 scores. Mean postoperative pain evolution, black line. Five subjects with the highest PCA1 scores, red lines; five subjects with the lowest PCA1 scores, blue lines. Abbreviation: PCA, principal component analysis.

Figure 5

Recovery time estimated by PCA2. Notes: (A) PCA2 accounted for 12.3% of the total pain variability. Mean postoperative recovery time evolution, black line; mean value +2 standard deviations, red line; mean value -2 standard deviations, blue line. (B) Extreme PCA1 scores. Mean postoperative recovery time evolution, black line. Five subjects with the highest PCA1 scores, red lines; five subjects with the lowest PCA1 scores, blue lines. Abbreviation: PCA, principal component analysis.

Figure 6

Postoperative pain intensity evolution by rescue medication. Notes: Mean postoperative pain in the group that took rescue medication, black line. Mean postoperative pain in the group not taking rescue medication, gray line. Abbreviation: VAS, visual analog scale.

Figure 7

HAD questionnaire after ASA procedure. Notes: Median values, black lines; mean values, black squares. Abbreviations: ASA, advanced surface ablation; HAD, Hospital Anxiety and Depression.