Pain evaluation and control during and following the treatment of hypertrophic scars and keloids by contact and intralesional cryosurgery--a preliminary study.

ABSTRACT

BACKGROUND: Intralesional cryosurgery effectively treats hypertrophic scars and keloids (HSK), but pain experienced by the patient during treatment can limit the application of cryosurgery. OBJECTIVES: To characterize the pain response during cryosurgical treatment of HSK, and to evaluate the pain experienced during contact and intralesional cryosurgery that employs a pain-control protocol. METHODS: Twenty-nine patients (17 women, 12 men) aged 17 years and older (mean ages 31.9±12.5 and 38.9±18.6 years, respectively, P=0.24), who were treated for a total of 36 HSKs by intralesional (n=20; 22 cryotreatments) or contact (n=9; 14 cryotreatments) cryosurgery were evaluated. The pain-control protocol involved oral pain-relief tablets (Dipyrone) and translesional local anaesthesia with Bupivacaine hydrochloride 0.5%. Pain evaluation according to the Visual Analogue Scale (VAS) (0-10 cm) was compared between the two groups at three time points during cryosurgery, immediately after it, and 4 h later. Scores ≤3 cm were considered to define the 'zone of analgesic success'. These results were compared with control data (contact cryosurgery without a pain-control protocol; n=56). RESULTS: Pain in the intralesional group was significantly lower than that in the contact group during and immediately after cryotreatment. During mean VAS=1.68±2.21 vs. 5.07±4.01 cm; median VAS=0.5 vs. 5.5 cm, respectively; P<0.0001. Immediately after mean VAS=1.22±1.77 vs. 5.38±3.81 cm; median VAS=0 vs. 6.0 cm, respectively; P=0.001. The control group had more pain during treatment (mean VAS=5.34±2.31, median=6.0) and 4 h later (mean=3.79±2.35, median=4.0) than the intralesional group (P<0.0001 and P=0.988, respectively). The pain level in the control group during the cryotreatment did not differ from that in the contact group (P=0.988). In the intralesional, contact and control groups analgesic success (VAS ≤3 cm) was achieved in 77.3%, 35.7% and 33.9%, respectively, of cases (P=0.002) during cryotreatment, and in 54.5%, 42.9% and 33.9%, respectively, of cases 4 h after treatment (P=0.24). CONCLUSIONS: The pain-control protocol significantly reduced pain severity to tolerable levels (VAS ≤3 cm) during and following intralesional and contact cryosurgery. Intralesional cryosurgery caused the least pain during and immediately after treatment.