Congenital laryngo-tracheo-esophageal clefts: updates from a quaternary care pediatric airway unit

All patients operated after March 2012 were prospectively entered into a LTEC registry since our units’ last publication on this subject [7]. For this study, we reviewed cases entered in this registry up to July 2022. A total of 25 patients underwent surgical repair for LTEC during this time frame at our hospital. After obtaining institutional board review approval and local ethics committee authorization (CER-VD 2020-00641), records of all patients were analyzed.

We included all pediatric patients with the diagnosis of LTEC, except those who were already described in our previous articles [5, 7]. All patients were referred to our unit from other Swiss and European hospitals and had at least one post-LTEC repair endoscopy at our institution. Feeding evaluation (functional oral intake scale FOIS) [8], Modified Barium Swallow (MBS) and diagnostic endoscopy were already done at these centers and the patients were referred to us purely for surgical repair of the cleft. Information regarding the subsequent follow-up was obtained by electronic mail exchanges with the referring doctors and parents/guardians of the patients. A follow-up registry is maintained in our unit and is regularly updated depending on the patient information received from these centers. The information provided in this report covers the entire study period and up to the most recent follow-up of the patient by his treating doctor.

Every patient underwent a diagnostic endoscopy under general anesthesia and spontaneous ventilation to assess the LTEC as well as other aero-digestive comorbidities/malformations. A laryngeal spreader was used to see the lower extent and the length of the cleft. The modified Benjamin–Inglis system was used for staging the cleft [5]. This classification system (Fig. 1) staged the clefts depending on its extension through the cricoid (partial or complete); the trachea (extra- and intra-thoracic) and the bronchi. The referring institutions followed similar endoscopy technique and cleft classification.

Tubeless and total intravenous anesthesia plays an important role during the endoscopic closure of the LTEC. The larynx and the trachea were sprayed with local anesthesia 0.5% Novesine (Oxybuprocaine) and it was repeated every 30–45 min. Dexmedetomidine (DMT) was started at the concentration of 1 µg/0.1 ml with a bolus of 4 µg/kg/hr over 10 min, following which, continuous perfusion of DMT (2–4 µg/kg/hr) and remifentanil (0.1 µg/kg/min) was administered. A Portex Blue Line endotracheal tube (ETT) maintaining oxygenation of 6L/min was passed nasally and placed in the hypopharynx, away from the laser field. During the entire procedure, the patient had cardiac monitoring, CO₂–O₂ saturation and the BIS (BiSpectral Index, Medtronic) recording. A second small-for-age Portex blue line soft ETT was kept ready for an oro-tracheal intubation without removing the suspension laryngoscope. The tube was passed into the trachea under endo- or microscopic guidance using a microlaryngeal curved crocodile forceps until the child regained adequate saturation.

Endoscopic approach (Fig. 2): An adequate-size Parsons laryngoscope with side slot (ref. 8576 C, D, E) was selected and inserted through the vocal cords to spread them apart and expose the most distal limit of the cleft and simultaneously visualizing the esophagus, and the trachea.

We used the Lumenis Duo CO2 laser (ultrapulse mode, 1 W, sharp focus 250 microspot) mounted on a Leica PROVido microscope for the endoscopic intervention. We started at the distal extremity of the cleft and, coming from caudal to cranial ends of the cleft, created two mucosal layers (trachea–laryngeal (TL) and eso-pharyngeal (OP)) up to just below the cuneiform cartilages on either side of the cleft. Hemostasis was achieved using a fine monopolar cautery point and adrenaline-soaked cotton pledgets. We used 5.0 Vicryl (TF-1 Plus, Ethicon, ref. V133H needle size 10 mm in most cases) or 7.0 Polydioxanone (Ethicon, PDS-II, needle size 9.3 mm in very small infants and neonates, ref. Z1701E) to suture the two mucosal layers, beginning from the caudal end and progressing up to the cranial end of the cleft. The sutures in both the mucosal layers were tied toward the esophageal side, and the sutures on the trachea–laryngeal layer were cut close to the knot. The laryngoscope was progressively withdrawn to place more cranial sutures. Fibrin glue (Tisseel) was placed between the two mucosal layers just before tying the most cranial suture. Depending on the cleft length, total of 2 (type I)–20 (types III and IV) sutures were used to close the cleft.

Combined approach (Fig. 3): This approach was used for long clefts (types III and IV) either as an upfront primary surgery or after a repair breakdown. If the patient had a prior LTEC surgery in another center, surgery at our institution was performed after a waiting period of at least 4–6 months following the prior surgery. All our patients had a prior tracheostomy. The surgery started with a microscopy-assisted ‘laser tattooing’ of the cleft, and then followed by an open repair. Thin mucosal attachments in a near-complete breakdown of a previously operated long cleft were laser divided. Laser marking of the cleft has the advantage of clearly demarcating the two mucosal layers (TL and OP), which could then be identified during the open repair. The next step was to perform a full laryngofissure. The OP mucosal closure was made from caudal to cranial ends of the cleft using 5.0 Vicryl and the sutures are cut toward the esophageal side. A rib cartilage graft was harvested and sculpted to have cranial and caudal perichondrial extensions. The cartilage was fixed to replace the dehiscent posterior cricoid plate, and the perichondrial extensions remained interposed between the OP and TL mucosal layers. The TL layer was closed with separate 5.0 Vicryl sutures knotted toward the airway. A small-for-age Monnier’s’ laryngo-tracheal LT-Mold avoiding decubitus on the cleft sutures was placed and doubly fixed (in the supraglottis and trachea) using 3.0 Prolene. The laryngofissure was closed using multiple intermittent 4/5.0 Vicryl sutures.

Following an endoscopic repair, the patients were given non-invasive ventilation, transferred to the pediatric intensive care unit, and received antibiotics and proton pump inhibitors. When the ventilatory assistance was waived and no signs of complications were present, the patient was transferred to a standard room. First LTEC repairs and re-operated patients were similarly managed in the post-operative setting.

All patients underwent a surveillance endoscopy under general anesthesia and spontaneous respiration at one-week post-surgery and a dilute methylene blue (MB) test was performed. An adequate-size suction catheter was passed through the nose and then under endoscopic vision into the esophagus. Methylene blue was injected into the catheter that was withdrawn up to the cricopharyngeal opening and its spill over into the airway was avoided. A mild laryngeal massage was given to the neck to allow distribution of the instilled MB over the entirety of the cleft. The integrity of cleft closure was checked by passing a long telescope in the airway up to the lower limit of the cleft. Residual cleft at the proximal end and any fistulization of MB was noted.

In the combined approach, the LT-Mold was kept for 6–8 weeks and removed under suspension laryngoscopy. Integrity-check of the cleft closure was done as described earlier.

Some patients had MBS prior to their referral to our center. Swallow therapists of our hospital evaluated patients before and after the surgery and oral feeds were started only after confirming optimal cleft closure during post-operative endoscopy. No MBS was performed in the post-repair period, swallowing evaluation was done by FOIS analyses.

Seven patients were born preterm, with four of them from a multiple pregnancy (two each from a twin and a triplet pregnancy). The most common synchronous airway lesion was tracheobronchomalacia (5 patients; 20%). Four patients had a confirmed genetic syndrome (2 had trisomy 21, 1 had chromosome 13 duplication, and 1 had G6PD deficiency). Two patients had dysmorphic facies and one had VACTERL association.

There were multiple other malformations, specifically gastro-intestinal (n = 9, 36%, esophageal atresia, microgastria, diaphragmatic hernia, omphalocele, and umbilical hernia); airway malformations (n = 8, 32%, supraglottic stenosis, subglottic stenosis, tracheoesophageal fistula, cricoid hypoplasia, pig bronchus, left lung agenesis), cardiac (n = 4, 16%, atrial and ventricular septal defect, patent ductus arteriosus, patent foramen ovale), and genitourinary (anal atresia, recto-vaginal fistula, hypospadias). One patient had preoperative left vocal cord palsy.

Seven patients had no malformation or comorbidity other than an isolated LTEC.

Five patients (20%) had endoscopic repair attempted for LTEC prior to their referral to our clinic. 9 patients (36%) had past gastro-intestinal surgery, 3 (12%) had an airway surgery and 2 (8%) a cardiac surgery. 12 patients (48%) had no history of any prior surgery.

Most common complication observed was partial to complete cleft repair breakdown, seen in 28% of the patients (n = 7). Other complications observed were pneumonia (n = 3), pulmonary hypertension (n = 1), and cricopharyngeal narrowing (n = 1). 7 patients needed at least one additional corrective surgery for a failed cleft repair, of which 5 were corrected with one or more revision endoscopic procedures, and two patients received the combined approach. One patient (#24) had surgery-related death. No patient had post-operative vocal cord immobility, except the one who already had prior left vocal cord palsy.

Preoperatively, most patients (n = 18, 72%) needed feeding assistance in form of percutaneous endoscopic gastrostomy (n = 6), nasogastric tube (n = 6), jejunostomy (n = 5) and total parenteral nutrition (n = 1). After the LTEC correction, 13 out of 18 patients (72%) resumed adequate oral feeding. The mean FOIS scores pre- and post-surgery recorded were 3 and 4.5, respectively. In low-grade LTEC (I–II), the feeding assistance was weaned off in all 6 patients, as opposed to high-grade LTEC (III–IV), wherein the feeding assistance was weaned off only in 7 (63%) out of 11 patients (excluding patient #24).

The present study has several limitations, the first being the limited sample size. However, the largest databases published are of similar size and is due to the rarity of the condition studied. Second, the length and quality of the follow-up are suboptimal and this is because most patients were referred to us from abroad. As a result, it was difficult to keep a standardized follow-up protocol and observations made by different doctors in different countries render the comparison of observations somewhat biased. This problem could be solved by developing a standardized questionnaire for the follow-up that is submitted at a fixed timeline to minimize the inter-observer bias. Third, its retrospective and observational study design.