Abstract

Minimally invasive repair of pectus excavatum (Nuss) operation is the current choice of surgical treatment for pectus excavatum deformities. Technical pitfalls arise in patients with previous thoracic and/or cardiac surgical interventions, due to severe intrathoracic fibrous adhesions. Herein, we describe an original modification technique in a patient with bilateral apical wedge resection and total pleurectomy due to recurrent spontaneous pneumothorax episodes within the past two years. Correction was performed by opening the pleura bilaterally and retrosternal release with digital palpation via a subxiphoid incision, to help to guide the introducer and the pectus bar, without a videothoracoscopic visualization.

Several technical modifications have been described for the minimally invasive surgical correction of pectus excavatum, the most common congenital chest wall deformity, since the Nuss procedure was first described by Dr. Donald Nuss[1] in 1987. The use of a subxiphoid incision with video assistance is also one of these modifications in patients with very profound deformities.[2] Herein, we describe a novel technique: a small additional subxiphoid incision and manual finger guidance for opening right and left parietal pleurae with retrosternal blunt dissection, which ensured safe passage of the introducer between the pericardium and sternum, without the routine use of videothoracoscopic guidance.

SURGICAL TECHNIQUE
A 29-year-old male patient presented with complaint of cosmetic deformity on his chest wall. No pathological finding was found, except for symmetrical mild pectus excavatum (Figure 1a). His medical history revealed seven pneumothorax episodes (right sided four times and left sided three times) over the last two years. He underwent bilateral apical wedge resection and total pleurectomy operations, by videoassisted thoracoscopic surgery (VATS) for right and by mini-thoracotomy for left hemithorax. His thoracic computed tomography revealed a Haller Index of 3.5 (Figure 1b). Based on these findings, we decided to perform Nuss procedure without directly entering the "hostile" thoracic cavity to prevent any parenchymal or cardiac damage. A written informed consent was obtained from the patient.

Figure 1: (a) Previous operative scars and pectus excavatum deformity, (b) with a Haller Index of 3.

The patient was placed in the supine position. The planned entrance and exit points for the bar were preoperatively marked on the anterior chest wall. In addition to the standard two anterior axillary incisions and subcutaneous pockets, a small subxiphoid incision was made, allowing passing a finger underneath the retrosternal area (Figure 2a). Initially, both pleurae were opened bilaterally, and caudal half of the sternum was released from the pericardium with blunt finger dissection. Subsequently, dense adhesions were freed between the parenchyma and the anterior chest wall until the marked exit points. The introducer was passed through the right subcutaneous tunnel and entered the hemithorax with the surgeon"s fingertip right under the planned intercostal level, to avoid any parenchymal damage. With finger guidance, it was pushed out of the subxiphoid incision. A ligature was tied to the pinhole of the introducer and pulled back through the right incision (Figure 2b). The same procedure was repeated for the left side, and free end of the ligature was pulled out from the left incision (Figure 2c).

Figure 2: (a) Opening of pleurae and substernal-pericardial release by blunt dissection via subxiphoid incision. (b) Introducer passed through the hemithorax and pushed out of the subxiphoid incision under tactile guidance. (c) The ligature tied to the pinhole of the introducer and pulled back through the lateral incisions. (d) Bar flipped with bilateral rotators.

A bar was shaped and tied to the ligature on the right side. It was passed through the pre-created tunnel, entering the right hemithorax, passing between the sternum and the pericardium, and pulling out from the left hemithorax. All were performed under digital palpation through the subxiphoid incision. The bar was, then, flipped 180º with rotators (Figure 2d) and fixed with bilateral stabilizers. No exsufflation was performed. The incisions were closed and the patient was extubated in the operation room. Postoperative course was uneventful.

Discussion

Minimally invasive pectus repair was first performed by Dr. Nuss[1] in 1987, and became the worldwide procedure of choice for correction, after successful clinical 10-year-outcomes were published in 1998.[2]

Limited surgical trauma and small scars are certain advantages of the Nuss procedure. However, serious complications or even mortality have been reported; and the risk is high, particularly in complicated patients with very profound deformities, previous cardiothoracic surgical interventions, and advanced intrathoracic adhesions.[3-5]

Several technical modifications were recommended to prevent these injuries. The use of left-sided thoracoscopic visualization or an additional subxiphoid incision was advocated, while other surgeons preferred the use of right-sided thoracoscopy with the impression that the mediastinal dissection of the substernal pericardial tissue was achieved with superior vision.[2,3] Additionally, the use of bilateral thoracoscopy has been described, both in children and adults, to ensure that the bar between the sternum and mediastinum is passed and placed safely.[4,5] To the best of our knowledge, our non-thoracoscopic modification of the Nuss procedure with the subxiphoid access has not been previously reported.

In conclusion, compared to the open Ravitch or standard Nuss procedure, our non-thoracoscopic modification can be considered safer and still a minimally invasive cosmetic procedure, with an additional 1.5 cm subxiphoid incision. This novel approach can be preferred, particularly in very young patients with an undersized and insufficient hemithoracic cavity for videothoracoscope installation, or in patients having a previous thoracic surgery,and those in whom severe intrathoracic adhesions are expected.

Declaration of conflicting interests
The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Funding
The authors received no financial support for the research and/or authorship of this article.

References

1) Nuss D, Kelly RE Jr. Minimally invasive surgical correction of chest wall deformities in children (Nuss procedure). Adv Pediatr 2008;55:395-410.

2) Hendrickson RJ, Bensard DD, Janik JS, Partrick DA. Efficacy of left thoracoscopy and blunt mediastinal dissection during the Nuss procedure for pectus excavatum. J Pediatr Surg 2005;40:1312-4.

3) Bouchard S, Hong AR, Gilchrist BF, Kuenzler KA. Catastrophic cardiac injuries encountered during the minimally invasive repair of pectus excavatum. Semin Pediatr Surg 2009;18:66-72.

4) Huang PM, Wu ET, Tseng YT, Kuo SW, Lee YC. Modified Nuss operation for pectus excavatum: Design for decreasing cardiopulmonary complications. Thorac Cardiovasc Surg 2006;54:134-7.

5) Cheng YL, Lee SC, Huang TW, Wu CT. Efficacy and safety of modified bilateral thoracoscopy-assisted Nuss procedure in adult patients with pectus excavatum. Eur J Cardiothorac Surg 2008;34:1057-61.