Prediction of Postoperative Pain After Mohs Micrographic Surgery With 2 Validated Pain Anxiety Scales Andrea F. Chen, MD,* David C. Landy, MD, MPH, PhD,† Erik Kumetz, BS, MA,† Gerard Smith, BS,† Eduardo Weiss, MD,‡x and Eli R. Saleeby, MDx

BACKGROUND Anxiety toward pain has been shown in several studies to increase postoperative pain after surgical procedures. This anxiety can be measured by several validated questionnaires, the Pain Catastrophizing Scale (PCS) and the Pain Anxiety Symptoms Scale (PASS). Higher scores on these scales correlate with increased pain after surgery, but this has not yet been demonstrated in dermatologic surgery. OBJECTIVE (MMS).

To assess whether pain anxiety will predict postoperative pain after Mohs micrographic surgery

MATERIALS AND METHODS Patients at 2 private Mohs practices were recruited to fill out 2 pain questionnaires, the PCS and the PASS. Their postoperative pain was assessed after MMS. RESULTS Three hundred fifty-six patients completed the study. Overall, most patients experienced little postoperative pain after Mohs surgery. However, for people with high anxiety toward pain, they also experienced statistically significant greater postoperative pain. Other factors that contributed to greater postoperative pain included female gender and lower extremity location. Second intention healing had lower pain than other repair types. CONCLUSION This study shows that postoperative pain is affected by pain anxiety, even in dermatologic surgery. However, most patients still had very little discomfort after surgery, further supporting MMS as an effective and safe procedure with relatively few postoperative problems. The authors have indicated no significant interest with commercial supporters.

P

ain after Mohs micrographic surgery (MMS) is often minimal, leading many surgeons to use only over-the-counter acetaminophen for initial management. Although this approach is effective for most patients who report minimal to no discomfort after surgery, a subset requires additional attention and either call to request medications or describe poorly managed pain at the postoperative visit. Firoz and colleagues1 found that postoperative pain after MMS in 433 patients was greatest on the day of surgery and greater in patients with flap repairs, younger than 66 years, number of lesions, and consumption of narcotics for pain relief. A similar study of 158 patients found greater pain in

patients with surgery on the scalp or multiples sites on the same day but did not find an association with age, gender, or closure type.2 It is also possible that postoperative pain levels are influenced by patient anxiety toward pain and other psychological factors.3 Several validated scales predict patient pain based on their anxiety and general outlook. The Pain Catastrophizing Scale (PCS) measures “catastrophizing” and is based on the finding that “catastrophizers” experience greater pain and more pain-related distress.4 The PCS predicts postoperative pain in other specialties and was

*Department of Dermatology, The Rendon Center for Dermatology, Boca Raton, Florida; †School of Medicine, University of Miami, Miami, Florida; ‡Department of Dermatology and Cutaneous Surgery, Miller School of Medicine, University of Miami, Miami, Florida; xSkin Institute of South Florida, Coral Springs, Florida

·

© 2014 by the American Society for Dermatologic Surgery, Inc. Published by Lippincott Williams & Wilkins ISSN: 1076-0512 Dermatol Surg 2015;41:40–47 DOI: 10.1097/DSS.0000000000000224

·

·

·

40

Copyright © American Society for Dermatologic Surgery. Unauthorized reproduction of this article is prohibited.

CHEN ET AL

recently shown to predict disability after carpal tunnel relsease.5,6 The Pain Anxiety Symptoms Scale (PASS), assesses anxiety about pain through measuring cognitive anxiety, fear, escape/avoidance tendencies, and somatic anxiety. Higher PASS scores have been shown to predict how a patient will experience pain and some pain behaviors.7 Neither the PCS nor PASS has been assessed as a predictor of postoperative pain after dermatologic surgery. Although many patients experience low pain levels after dermatologic surgery, some patients have a much more painful postoperative experience than they or their surgeon were expecting, prompting feelings of fear or anger toward their doctor. The ability to more accurately predict the patients who may require stronger analgesic medication or a nextday postoperative visit will be helpful in best caring for those patients. This study sought to investigate the correlation between pain anxiety and postoperative pain after Mohs surgery, hypothesizing that higher scores on 2 pain anxiety scales would correlate with greater pain after surgery. Additionally, demographic and clinical predictors of postoperative pain after Mohs surgery were assessed to compare with published findings. Methods All patients older than 18 years, able to read English, and undergoing MMS in 2 private practice offices from October 2012 through May 2013 were invited to participate in the study. The study protocol conformed to the guidelines of the 1975 Declaration of Helsinki. After informed consent was obtained, patients completed the PCS and PASS questionnaires. Demographic and clinical characteristics were obtained before surgery with the number of stages, postoperative size, and type of repair recorded after surgery along with the patient’s phone number. Patients were called within 48 hours after surgery. Their pain was assessed on a scale from 0 to 10, 0 being no pain and 10 being the worst pain they could imagine. If the patient could not be reached after at least 2 attempts, they were excluded from the study to ensure their memory of any pain was fresh. The patient reported 2 scores during the call: a score for the day of surgery and

a score for the day after surgery. Preoperative and postoperative instructions remained exactly the same as per the individual practice’s protocol. Patient data were anonymously entered into a spreadsheet. Pain anxiety scores were tabulated. The patient’s maximum pain score was used in the analysis. As some patients remained anesthetized the day of their surgery, the maximum pain over the 2 days was believed to better represent their actual postoperative pain. Surgery sites were grouped as follows: face (excluding nose and ear), nose, ear, scalp, neck, trunk, upper extremity, and lower extremity. Closure types were grouped as follows: complex, adjacent tissue transfer, secondary intention, and an other category, which included repair by an outside physician, grafts, and xenografts. The frequencies of outside repair by plastic surgeons, grafts, and xenografts were small, so these were grouped together for analysis. Patients often did not know what type of repair they received by the plastic surgeon, so that is why these were grouped in the other category. Descriptive statistics were used to summarize demographic and clinical characteristics. Pain anxiety and postoperative pain scores were described using histograms. Associations of demographic and clinical characteristics with pain anxiety scores were assessed using Spearman rho for continuous variables, the Wilcoxon rank-sum test for dichotomous variables, and the Kruskal–Wallis test for other categorical variables. Associations of demographic and clinical characteristics with postoperative pain scores were assessed similarly. For tumor diagnosis, the “other” group was excluded from statistical comparisons. For location, associations were described using box plots. Associations between pain anxiety scores and postoperative pain were first described using scatter plots. Given the nonlinear piecemeal nature of the association suggested by the scatter plots and the non-normal distributions of the variables, associations were then described using Spearman rho. Because of the association between gender and postoperative pain, these associations were reexamined within gender subgroups to evaluate potential confounding and effect modification. Patients were then grouped by pain

41:1:JANUARY 2015

41

Copyright © American Society for Dermatologic Surgery. Unauthorized reproduction of this article is prohibited.

PREDICTING POSTOPERATIVE PAIN

anxiety and postoperative pain scores compared across groups using a series of Wilcoxon rank-sum tests. To better describe the piecemeal nature of the associations, local polynomial smoothing regression was performed using the lpoly command, and 95% confidence intervals obtained to describe precision. All analyses were performed using STATA 9.2 (StataCorp LLC, College Station, TX). All p values are 2-sided and considered significant at less than .05. Results Characteristics Of 423 patients who completed the questionnaires and were entered this study, 356 (84%) were reached by phone within 48 hours after surgery and included in this report (Table 1). The sample was nearly two-thirds male with most patients older than 65 years, although patients ranged from 30 to 97 years of age. Two-thirds of lesions were on the face and nose, with more than half diagnosed as basal cell carcinoma. Most lesions were under 2 cm in size pre-operatively and repaired using either a complex linear repair or adjacent tissue transfer.

TABLE 1. Characteristics of 356 Patients Undergoing Mohs Surgery Characteristic Sex Female

124 (35)

Male

232 (65)

Age, yrs 30–44

A higher score on both the PCS and PASS indicates a greater anxiety toward pain. For both scales, distributions were positively skewed, with the majority of respondents having lower pain anxiety scores (Figure 1). Of note, the PASS scale has several negatively scored questions, which is why there can be a negative score. Female sex and increasing tumor size were statistically significantly associated with higher pain anxiety scores (Table 2). Pain anxiety scores were not associated with age, tumor location, type of tumor, and closure type. Distribution and Associations of Postoperative Pain Scores The distribution of postoperative pain scores was positively skewed, with most patients reporting little to no pain (Figure 2). However, around 5% rated their pain a 10 of 10. Female sex was associated with greater postoperative pain (Table 3). Pain differed

42

4 (1)

45–64

80 (22)

65–79

157 (44)

80–97

115 (32)

Tumor location Face, not nose or ear

154 (43)

Nose

76 (21)

Ear Scalp

37 (10) 33 (9)

Neck

9 (3)

Trunk

8 (2)

Upper extremity

26 (7)

Lower extremity

13 (4)

Tumor type Basal

205 (58)

Squamous Unknown

147 (41) 2 (1)

Tumor size before procedure, cm

Prediction of postoperative pain after Mohs micrographic surgery with 2 validated pain anxiety scales.

Anxiety toward pain has been shown in several studies to increase postoperative pain after surgical procedures. This anxiety can be measured by severa...
508KB Sizes 0 Downloads 7 Views