Difficult situation in cancer pain: breakthrough pain* Situação difícil em dor oncológica: dor do tipo breakthrough

BACKGROUND AND OBJECTIVES: Breakthrough pain is frequent among cancer patients and is poorly studied in Brazil. This study aimed at evaluating the characteristics of breakthrough pain and at comparing its evolution during three days. METHODS: This is a longitudinal study where a specific questionnaire developed for the study was applied and was made up of socio-demographic data (age, gender, marital status, profession, income, origin), cancer-related data (types of primary tumor, presence of metastases, therapeutic approach with chemotherapy and/or radiotherapy, surgical treatment and drugs) and parameters related to breakthrough pain (number of daily episodes, duration of crisis, intensity, pain onset velocity and types of breakthrough pain: spontaneous, incidental, drug failure at the end of the dose). RESULTS: Most patients were females (71.7%), aged between 30 and 50 years (41.7%), under concomitant chemotherapy and radiotherapy (41.7%) and had cervical cancer (54.2%). Mean pain intensity was 7, with standard deviation of 2.3. With regard to breakthrough pain, there have been no statistically significant differences in the three evaluation moments. During the three evaluations, it was observed that there has been decrease in the percentage of patients with pain for more than 15 minutes in the third evaluation (p=0.004). There has been no difference in pharmacological profile among the three evaluations (p=0.34). CONCLUSION: Breakthrough pain was frequent among the studied population. The use of opioids was effective to decrease pain duration and spontaneous pain.