Li, N.L., Yu, B.L., Tseng, S.C., Hsu, C.C., Lai, W.J., Hsieh, P.F., . . . Chen, C.M. (2011). The effect on improvement of recovery and pain scores of paravertebral block immediately before breast surgery. Acta Anaesthesiologica Taiwanica: Official Journal of the Taiwan Society of Anesthesiologists, 49(3), 91–95.

To investigate whether paravertebral block (PVB) implemented immediately before breast cancer surgery can affect pain and emesis and improve the quality of life of patients after breast cancer surgery

Consecutive patients received general anesthesia or PVB plus anesthesia before breast cancer surgery. Researchers compared the pain scores of both groups of patients at one hour and at six hours postoperatively and at midmorning of postoperative day 1 (POD1). At one hour, patients were observed in the postanesthesia care unit for one hour, where they were provided with analgesics to achieve a pain score of less than 4 on the Numeric Rating Scale (NRS). Choices of analgesic for patients with moderate to severe pain included intravenous morphine, 3–6 mg, and intravenous ketorolac, 30 mg. Patients with mild to moderate pain (a score of 4–7) received acetaminophen, 500–1000 mg, at the patient’s request. At six hours after surgery and on POD1, pain scores were recorded with patients at rest and during movement. Movement consisted of moving the arm until the arm and body were at a 90-degree angle. The amount of postoperative narcotics and the time to first request for pain medication was recorded.

• The sample was composed of 40 patients; presurgery, 25 received general anesthesia only and 15 received general anesthesia and a PVB.
• In the general anesthesia group, mean patient age was 50.4 years. In the group that received general anesthesia and PVB, mean patient age was 54.2.
• All patients were female.
• All patients had breast cancer. In the group that received general anesthesia only, four patients underwent modified radical mastectomy and 21 underwent a breast-conserving procedure. Of patients that received PVBs, one underwent modified radical mastectomy and 14 underwent a breast-conserving procedure.

• Single site
• Inpatient
• Taiwan
   

• Phase of care: active treatment
• Clinical applications: end of life and palliative care

Intervention study

• Quality-of-recovery (QoR) tool, 0–18 scale
• Numeric Rating Scale for pain, 0–10 scale
• Apfel risk score for postoperative nausea and vomiting (PONV)
• American Society of Anesthesiologists (ASA) physical status classification

• Compared to pain scores in the general anesthesia (GA) group, pain scores were significantly lower in the GA + PVB group at one hour (p < 0.0001), six hours (p < 0.0001), and at midmorning on POD1 (p = 0.041). SImilarly, in the GA + PVB group, pain scores with movement were lower at all three time points: one hour and six hours, p < 0.0001; POD1, p = 0.0012.
• The median QoR scores were higher in the GA + PVB group than in the GA group. At six hours, the median QoR score in the GA group was 12; in the GA + PVB group, 18, (p < 0.0001). At 10 a.m. on POD1 the mean QoR score in the GA group was 16; in the GA + PVB group, 18 (p = 0.0079).
• In the GA group, median cumulative postoperative analgesic consumption was four doses; in the GA + PVG group, 1 dose (p < 0.0001).
• In the GA group, median cumulative postoperative narcotic consumption was 1 dose; in the GA + PVB group, 0 dose (p = 0.001).
• Median time from the end of the operation to the first request for analgesia differed significantly between the two groups. In the GA group, the median time was 30 minutes; in the GA + PVB group, 435 minutes (p = 0.0002).
• Incidence of PONV was higher in the GA group (64%) than in the GA + PVB group (6.67%) (p < 0.001). 
• Patients in the GA group had significantly greater (p < 0.00001) antiemetic use overall than did patients in the GA + PVB group.

After breast cancer surgery, PVB plus GA may provide better pain relief than does GA alone. The researchers observed higher QoR scores and less antiemetic use in the GA + PVB than in the GA group.

• The study had a small sample size, with fewer than 100 patients.
• The study was conducted at a single site.
• Only 15 patients received the intervention.
• The study contained no randomization.
• At baseline, patients in the GA group used more antiemetic than did patients in the other group, a fact that makes results difficult to interpret.
   

PVB may be a useful tool to decrease pain after breast cancer surgery and to reduce PONV, but more research is needed before researchers can draw definitive conclusions.