Thermoreactive clips do not reduce sternal infection: a propensity-matched comparison with sternal wires

OBJECTIVES

Sternal stability is essential to prevent serious infective complications after sternotomy. This paper examines whether nitinol thermoreactive clips reduce sternal wound infection rates in obese patients [body mass index (BMI) ≥30] compared with sternal wires.

METHODS

All patients with BMI ≥30 undergoing cardiac surgery via median sternotomy between February 2008 and February 2013 in our institution were divided into two groups depending on sternal closure technique-sternal wires or thermoreactive clips. Comparison was made using propensity-matched analysis with sternal wound infection as the primary outcome.

RESULTS

Of 1371 patients, 826 (60%) had thermoreactive clips and 545 (40%) sternal wires. The sternal wires group was older (mean age 66.62 ± 10.1 vs 64.35 ± 9.8 years, P = 0.00) with a greater proportion of females (39 vs 26%, P = 0.00). In unmatched group comparison, both superficial sternal wound infection (thermoreactive clips 4% vs wires 3%) and deep infection (thermoreactive clips 3% vs wires 0.6%, P = 0.00) were more common in the thermoreactive clips group. More patients in the thermoreactive clips group required debridement and a larger number had vacuum-assisted closure [thermoreactive clips 10 patients (1%) vs sternal wires 2 (0.4%)]. Propensity-matching yielded two groups of 356 patients. There was no difference in sternal wound infection rates [thermoreactive clips 19 patients (5%) vs sternal wires 15 (4%), P = 0.58] or deep sternal infection rates [thermoreactive clips 9 patients (3%) vs sternal wires 3 (1%), P = 0.11].

CONCLUSIONS

Thermoreactive clips did not have an advantage in the prevention of superficial or deep sternal wound infection in obese patients undergoing sternotomy.

Thermoreactive nitinol clips: Propensity score comparison with Robicsek technique

Objective

To compare the use of thermoreactive nitinol clips with the classic Robicsek technique for treatment of sternal dehiscence after cardiac surgery.

Methods

Eighty-two (2.3%) of 3564 open heart surgery patients underwent reoperation for sternal dehiscence between October 2011 and 2012. Prospectively collected data from 26 (31%) consecutive patients who underwent reoperation using thermoreactive nitinol clips were compared with those of a retrospective cohort of 42 (51.2%) who were treated with the classic Robicsek technique. To overcome baseline and operative variations, we constructed a propensity model using logistic regression.

Results

Overall mortality occurred in 3 (5%) patients and a second revision was performed in 2 (7.7%) in the nitinol clip group and 2 (6.3%) in the control group ( p > 0.05). Postoperative results were similar except for the mean time of operation which was significantly shorter in the nitinol clip group, and patients in this group required substernal dissection slightly less frequently than those in the control group.

Conclusions

Thermoreactive nitinol clips allow the surgeon to perform a rapid and less challenging technique for sternal reoperations, without additional complications. Using this technique in an identical group with a finite sample size, we accomplished similar early results to those of the classic Robicsek technique.