Influence of Deep Serratus Anterior Plane Block on Chronic Pain at 3 Months After Breast-Conserving Surgery: Prospective, Cohort Study.

OBJECTIVES

In 2015, we evaluated our practices regarding pain after breast-conserving surgery. Thereafter, we have adapted our practices by performing a systematic deep serratus plane block before the surgical incision. In 2019, we assessed the impact of these changes in terms of chronic pain. The main objective of this study was to evaluate the prevalence of chronic pain 3 months after this type of surgery.

MATERIALS AND METHODS

All patients treated with breast-conserving surgery as outpatients were included in this prospective study between April and July 2019. After inducing general anesthesia, 20 mL of ropivacaine 3.75 mg/mL were injected under the serratus muscle. Morphine titration was performed in the recovery room according to pain scores. A pain and quality of life questionnaire was sent 3 months after surgery. A backward logistic regression model was applied to calculate the adjusted odds ratios.

RESULTS

The final analysis involved 137 patients. Three months after surgery, 43 patients (31%) reported persistent pain related to the surgery. Maximum pain in the last 24 hours was moderate to severe in 60% of cases, 16 patients (35%) took painkillers. Morphine titration in the recovery room was required in 25 patients (18%). Younger age and the use of lidocaine to prevent after injection of propofol during general anesthesia induction appeared to be protective factors for the risk of pain at 3 months (secondary endpoints).

DISCUSSION

No persistent pain at 3 months was reported in 69% of cases. Furthermore, the use of a deep serratus anterior plane block before the surgical incision has limited the need for morphine titration in the recovery room to <1 patient in 5. These evaluations of professional practices should be encouraged.