Efficacy of Blake drains for mediastinal and pleural drainage following cardiac operations.

BACKGROUND: Mediastinal and pleural drainage following cardiac operations has traditionally been achieved with large bore, semirigid chest tubes. The purpose of this study was to evaluate the safety and efficacy of drainage by means of small, soft, and flexible 19 F Blake drains.

METHODS: This is a review of all patients who underwent heart surgery over a 3-year period at a single institution. Chest tubes and Blake drains were removed on postoperative day 1 to 5 depending on patient's condition, amount of drainage, and surgeon's preference. The criteria for drain removal did not vary with type of drain.

RESULTS: There was no significant difference in the amount of drainage between both groups. Postoperative mediastinal exploration occurred in 3.47% of patients (12/346) in the chest tube group and in 2.08% of patients (8/385) in the Blake group (p = 0.27). Significant pleural effusions requiring a subsequent drainage procedure occurred in 9.54% of patients (33/346) in the chest tube group and in 9.87% of patients (38/385) in the Blake group.

CONCLUSIONS: No significant differences were noted in the number of mediastinal explorations in patients drained with conventional chest tubes as compared to Blake drains during cardiac operations. Though not statistically significant, there may actually be an advantage of Blake drains over conventional chest tubes in this regard. There was also no significant difference in the incidence of postoperative pleural effusions. Blake drains appear to be at least as effective and safe as conventional chest tubes in draining the mediastinum and pleural spaces following cardiac surgery.