Sidiropoulou, T., Buonomo, O., Fabbi, E., Silvi, M.B., Kostopanagiotou, G., Sabato, A.F., & Dauri, M. (2008). A prospective comparison of continuous wound infiltration with ropivacaine versus single-injection paravertebral block after modified radical mastectomy. Anesthesia and Analgesia, 106, 997–1001. 

To compare the efficacy of continuous wound infiltration with a local anesthetic with thoracic paravertebral block after breast surgery

Before surgery, patients were randomized to receive an ipsilateral paravertebral block or postoperative continuous wound infiltration with 0.5% ropivacaine. Two catheters delivered ropivacaine at a 2 m/L rate for each catheter. Pain assessments were done every four hours. All patients received the same anesthesia protocol.

• N = 48
• MEAN AGE = 65.5 years
• FEMALES: 100%
• KEY DISEASE CHARACTERISTICS: All patients had breast cancer and were receiving modified radical mastectomies.

• SITE: Single site  
• SETTING TYPE: Inpatient  
• LOCATION: Italy

• PHASE OF CARE: Active antitumor treatment

Randomized, parallel-group trial

• Visual Analog Scale (VAS) for pain
• Analgesia consumption
• Restricted movement because of pain

Patients in the paravertebral block group had lower pain scores and less restriction of shoulder movement in the first four hours (p < 0.005), and at 16–24 hours, patients  in the continuous wound infiltration group had lower pain scores (p < 0.02). There were no differences between groups in overall analgesic consumption. The incidence and severity of postoperative nausea and vomiting were higher in the wound infiltration group (p = 0.017). Median pain scores were low across all time points.

Both paravertebral blocks and continuous wound infiltration were effective for the management of postoperative pain. Although pain was lower in patients receiving continuous infiltration at later hours of observation, their incidence of postoperative nausea and vomiting was higher.

• Small sample (< 100)
• Risk of bias (no blinding)

Both neural blocks and continuous wound anesthetic infusions were effective methods for postoperative pain management in this study although wound infiltration was associated with more nausea and vomiting. Nurses need to consider the potential for postoperative nausea and vomiting associated with pain control interventions as well as the anesthetics used.