CTS combined with TB and PA sling is a life-threatening disease that is difficult to manage not only during surgery but also after tracheoplasty [3-5]. We modified a slide tracheoplasty technique for CTS combined with TB and PA sling.
The major findings of this study were as follows: (1) We modified the slide tracheoplasty technique to bring the TB and bifurcation closer and formed a wider triple-bifurcation shape; (2) All cases were complicated with PA sling at the bifurcation stenosis with tracheobronchomalacia and underwent posterior-anterior slide tracheoplasty with an inverted Y-shaped incision at the bifurcation and repositioning of the PA; (3) Postoperative ECMO management was required in 55.6% of cases; (4) There were no major intraoperative or postoperative complications, including hypoxic episodes and subsequent ischemic encephalopathy; and (5) All patients were discharged home without tracheostomy, and no patients showed tracheal stenosis, intratracheal granulation, or tracheomalacia during the long-term follow-up period.
TB is defined as a congenital anomaly in which the RULB arises directly from the trachea and above the tracheal bifurcation in the narrow sense [8]. Cases with CTS combined with TB tend to have a combination of tracheal abnormalities and cardiac anomalies, resulting in a high postoperative mortality rate [9,10]. Although various surgical procedures have been reported, which is the most appropriate tracheoplasty procedure remains controversial. Tracheal end-to-end anastomosis was performed for short-segment CTS cases with a stenotic trachea below the TB [1,11]. For cases with long-segment CTS, slide tracheoplasty described by Tsang and Grillo has been widely accepted and become the standard tracheoplasty procedure [1,2]. Left–right slide tracheoplasty for CTS with TB was reported to avoid the need for an incision and a suture line closing the orifice of RULB [12]. However, Morita et al. did not recommend this procedure, as their cases had severe tracheomalacia after left–right slide tracheoplasty and required tracheostomy. They pointed out two reasons for this complication with left–right slide tracheoplasty [4]. One reason was that a transverse figure-eight deformity occurred at reconstruction site and easily collapsed [5]. The other reason was that the tracheal walls receive their blood supply from the lateral surface of the trachea [13], and ischemia occurred in the central part of the trachea at the anastomotic site [9]. We therefore modified the posterior-anterior slide tracheoplasty technique for long-segment CTS below or above the TB, as reported by Beierlein and Elliott [12].
In our procedure, the stenotic trachea was transected just above the middle point between TB and tracheal bifurcation and then slide tracheoplasty was performed to make TB and tracheal bifurcation close forming a tracheal trifurcation. The tip of the endotracheal tube was able to be placed just above the TB after tracheoplasty. This allowed the suction tube to easily reach the anastomotic site without leaving a long distance from the intubation tube and prevented critical postoperative airway obstruction caused by edema of the anastomotic site and bloody secretions. We also performed another modification of the slide tracheoplasty technique for TB: the proximal segment of the trachea was incised slightly to the left lateral side of the dorsal midline (5 o’clock direction) in order to maintain the blood supply. The TB arises from the posterolateral aspect of the trachea in most patients [4], so this incision approach avoided the need to perform suturing near the orifice of the TB. In our study, airway obstruction was prevented in all cases at the TB and bifurcation using this method. As a result, all cases were able to be extubated safely.
PA sling is the most common cardiac anomaly and is complicated with CTS in 50%-65% of cases [14,15], causing airway obstruction in the neonatal and infant periods due to complete cartilage rings surrounded by PA. Tracheobronchomalacia at the bifurcation induced by compression of the vascular ring was found in 27% of cases, and this condition was a risk factor for mortality [16,6]. Muraji et al. reported the first survivor after concomitant reconstruction of extensive CTS and PA sling in 1998 [17]. However, the lumen of the tracheal bifurcation could not be enlarged sufficiently with conventional posterior-anterior slide tracheoplasty. Extubation was reportedly difficult in about 30%-40% of cases due to the flattened bifurcation after conventional slide tracheoplasty [18], requiring additional aortopexy, intratracheal stenting, and tracheostomy postoperatively [3,5,18].
Since 2005, we have performed an inverted Y-shaped incision for cases with tracheobronchomalacia at the tracheal bifurcation [6]. In all of or cases, no tracheobronchomalacia was recognized at the bifurcation after slide tracheoplasty, and extubation was achieved without additional surgery. This technique is thus worth attempting before considering other approaches, such as prolonged stenting and tracheotomy.
PA sling associated with CTS has a high rate of cardiac anomalies and a high mortality rate (up to 46%) [19]. This high mortality is due to the severity of cardiac anomalies in addition to the presence of CTS. Staged repair is beneficial for CTS with complex cardiac anomalies with keeping intra- and postoperative stable circulatory dynamics potentially affect the outcomes of combined tracheal and cardiac surgery [10]. In our institution, we proactively use postoperative ECMO management for CTS cases with severe cardiac anomalies, depending on the cardiac disease, to improve the survival rate.
Postoperative ECMO management was performed in 5 cases (55.6%). Three of them underwent continuous ECMO management during and after surgery, ultimately achieving ECMO/ventilator weaning and extubation without respiratory complications or hypoxic ischemic episodes following encephalopathy.