Mohamed, S.A.B., Abdel-Ghaffar, H.S., Kamal, S.M., Fares, K.M., & Hamza, H.M. (2016). Effect of topical morphine on acute and chronic postmastectomy pain: What is the optimum dose? Regional Anesthesia and Pain Medicine, 41, 704–710.

To determine if using a different morphine amount in a morphine/bupivacaine combination would be more effective in pain management in patients after a radical mastectomy for breast cancer.

Registered clinical trial with 90 patients allocated to receive 10 ml plain bupivacaine 0.5% plus either 5, 10, or 15 mg morphine diluted with saline 0.9% to 20 ml and topically to mastectomy site prior to closing. The three groups were compared for the following: time to first postoperative analgesia; IV patient-controlled analgesia (PCA) morphine consumption; pain scores; hemodynamics; sedation; adverse events in first postoperative 48 hours; and Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) scores in first and third postoperative months. Each patient participated in two study phases: an initial two-day treatment phase (48 hours post-op), phase 1, followed by a one- and three-month follow-up, phase 2. All clinical staff and patients were blinded to treatment group assignment.

• N = 90   
• AGE: Mean = 50.8 years (SD = 7.73) (morphine 5 mg: 50.43, SD = 7.84; morphine 10 mg: 49.83, SD = 7.78; morphine 15 mg: 52.13, SD = 7.65)
• FEMALES: 100%
• CURRENT TREATMENT: Not applicable
• KEY DISEASE CHARACTERISTICS: Patients with breast cancer

• SITE: Single site   
• SETTING TYPE: Multiple settings    
• LOCATION: Assiut University, Assiut, Egypt

PHASE OF CARE: Active anti-tumor treatment

Prospective, randomized, double-blind comparative study.

Visual analog scale (VAS), analgesia time, cumulative morphine consumption in first 48 hours, LANSS pain scale

There was a significant difference in analgesia-free time between the three groups. Morphine 15 mg had no patients requiring postoperative analgesics in the first 48 hours compared to 8 patients (27%) in the morphine 10 mg group and 19 patients (63%) in the morphine 5 mg group (p < 0.002). Regarding the time to analgesia use, the morphine 5 mg group was 7.31 hours (SD = 3.12) versus 14 hours (SD = 3.54) in the morphine 10 mg group (p < 0.000).

The morphine 15 mg group had the lowest LANSS recorded score in the first postoperative month when compared to the morphine 5 mg and 10 mg groups (1.1 [SD = 0.37] versus 5.76 [SD = 3.26] versus 4.73 [SD = 2.87], respectively) (p < 0.0001).

The increase in topical morphine (specifically up to 15 mg) in combination with bupivacaine, when compared to lower doses of morphine, has shown a decrease in postmastectomy pain through the reduction of analgesic use within 48 hours after surgery as well as lower LANSS scores within the first postoperative month.

• Small sample (< 100)
• Risk of bias (no control group)

15 mg topical morphine with bupivacaine may decrease postoperative pain and reduce the rate of PMPS.