Comparing the effectiveness of full-vacuum and half-vacuum drainage in reducing seroma after modified radical mastectomy: a meta-analysis.

Introduction: Owing to limited outpatient support for drain management, delayed discharge after mastectomy is more prevalent in developing countries. Utilising half-vacuum (HV) suction drains for routine drainage after mastectomy could lead to a reduced incidence of seroma and a shorter hospital stay. This systematic review and meta-analysis compared the outcomes of HV against full-vacuum (FV) suction drains in patients who underwent modified radical mastectomy for breast cancer.

Methods: Differences between the two groups in length of hospital stay, total volume of drain effluent and incidence of seroma were assessed. RevMan 5.4 was used to calculate the odds ratio (OR) and relative risk (RR) for dichotomous data, and the mean difference (MD) for continuous data.

Results: Nine randomised controlled trials were included in this review. Using HV drains reduced both the mean length of hospital stay (MD: -2.30 days, 95% confidence interval [CI]: -4.10 to -0.49 days, I²=97%) and the mean total volume of effluent (MD: -132.61ml, 95% CI: -207.32ml to -57.91ml, I²=88%) compared with FV drains. However, there was no statistically significant difference in incidence of seroma between the two groups (RR: 0.67, 95% CI: 0.30 to 1.46, I²=65%). Likewise, there was no difference in rate of seroma occurrence on sensitivity analysis (OR: 1.29, 95% CI: 0.72 to 2.33, I²=74%).

Conclusions: There was no difference in the incidence of seroma between HV and FV suction drainage. Conversely, a reduction in the length of hospital stay and the total volume of drain effluent was observed for mastectomy patients with a HV drain.