Prospective Randomized Study of Early Pulmonary Evaluation of Patients Scheduled for Aortic Valve Surgery Performed by Ministernotomy or Total Median Sternotomy

Objective

The purpose of this study was to compare the respiratory function of patients operated either with a ministernotomy or with a conventional sternotomy for an aortic valve replacement.

Design

A prospective randomized study.

Setting

A single-institution university hospital.

Participants

Seventy-eight patients scheduled for aortic valve replacement.

Interventions

Patients were assigned to have minimal sternotomy access (ministernotomy) or conventional median total sternotomy. Pulmonary function was measured using a mobile respiratory spirometric device preoperatively and after 1 (POD1), 2 (POD2), and 7 days (POD7) postoperatively.

Measurements and Main Results

There was no significant difference in any respiratory parameter measured between the 2 groups of patients. Almost all respiratory volumes decreased significantly with the same intensity in the 2 groups on POD1 (p <0.05), by about 50% from baseline. Only functional residual capacity was unchanged from baseline in the postoperative period, except for a small but significant reduction of this parameter to 60.3% ± 27.4% in the standard sternotomy group on POD1 and 60.9% ± 27.1% and 58.8% ± 30.4%, respectively, in the ministernotomy and the standard group at POD7. The only significant difference concerned the intraoperative blood loss measured at 450 ± 280 mL and 720 ± 450 mL, respectively, in the ministernotomy and the standard group (p < 0.05), but this was not significantly associated with a reduction of total blood use.

Conclusion

This study failed to show any improvement of respiratory function by a smaller chest incision. However, it showed a significant reduction in intraoperative bleeding but without a reduction in transfusion. Further investigations are required to assess whether this procedure could improve the outcome of cardiac surgery patients with a greater predicted risk score or pulmonary diseases.

Key Words: aortic valve, cardiopulmonary bypass, heart valve prosthesis implantation, postoperative complications, prospective studies, sternum, surgical procedures, minimally invasive, cardiac surgery, lung volume measurements, postoperative hemorrhage