Outcomes and Complications related to
Minimally Invasive Surgery for repair of Pectus Excavatum
​
Pectus excavatum is the most commonly occurring chest wall deformity and in appropriately selected patients, it can be corrected using the minimally invasive technique described by Dr. Donald Nuss. This
approach utilizes thoracoscopic visualization with small incisions and placement of a temporary metal
bar positioned behind the sternum for support, while the costal cartilages remodel. Since introduction,
the minimally invasive repair of pectus excavatum (MIRPE) has become accepted in many centers as the
procedure of choice for repair of pectus excavatum. In experienced hands, the procedure has excellent
outcomes, shorter procedural length, and outstanding functional and cosmetic results. However, proper patient selection and attention to technical details are essential to achieve optimal outcomes and prevent significant complications.
The spectrum of adverse outcomes related to the minimally invasive technique is somewhat variable, and most complications today are considered rare and unusual. Preliminary reports when the operation was considered ‘new’ suggested a higher rate of complications, with the most commonly reported complication being related to pectus bar displacement. The following is a list of reported complications
after MIRPE (and the estimated incidence for each):
• Pectus bar displacement—requiring reoperation (2.5%);
• Pneumothorax—requiring chest tube (3%);
• Overcorrection (3%);
• Epidural catheter related complications (4%);
• Bar allergy (1–2%);
• Wound infection (1%);
• Pleural effusion (1%);
• Thoracic outlet syndrome (<0.5%);
• Pericarditis (<0.5%);
• Cardiac injury (<0.5%);
• Sternal erosion (<0.5%);
• Death (<0.1%).
Of note, the overall morbidity of the procedure was initially reported to be high, at almost 20%, with the most common complication being bar displacement or rotation requiring reoperation. However, with improvements and modifications to the technique, complication rates have dropped by over 75%. Pre-operative screening for metal allergy has resulted in a decreased incidence skin rash and systemic reactions related to this unusual problem. Fortunately this problem will rarely require removal of the pectus bar. If metal allergy is identified pre-operatively, the patients should receive a Titanium bar for
the correction of the pectus. A recent analysis of Pediatric NSQIP data reported overall morbidity of MIRPE to be 3.8% with no mortalities identified in their dataset. Though complications after MIRPE are fairly rare today, it is important to recognize the impact of the procedural learning curve on declining rates and be aware that these data come from centers with extensive experience in the repair of chest wall deformities. Furthermore, though rare, mortality during or after the procedure has been reported. Given that pectus excavatum is a condition that rarely causes any life-threatening problems, it is especially important to educate patients and families on the risks associated with the operation, both bar insertion and removal, through discussion and patient education materials in order to allow all parties to make a calculated, well-informed decision about surgical treatment. Pectus bar removal surgery can usually be accomplished as an outpatient procedure, 3 years after the primary repair. Re opening of the lateral chest incisions and mobilization/ removal of the bar and stabilizer can be difficult if the patient has developed scar & calcifications around the bar. A traction technique is applied for pectus bar removal. It is important to pull the bar in such a way to conform to the patient’s chest in order to minimize risk of injury to mediastinal structures. The bar is pulled towards the floor and it can be unbent in the process using hand-held bar benders.
Pectus recurrence is considered very rare (less than 1%) if the pectus bar has been left in place for 3 years or more. As previously mentioned, patients with previous chest procedures, including open heart surgery and Ravitch repair of pectus, are considered to be at higher risk for life- threatening complications due to the likelihood of intra-thoracic adhesions. One of the critical steps of the minimally invasive operation is the insertion of the pectus bar passer across the anterior mediastinal space and the placement of the pectus bar. This can be challenging, particularly in older patients with a severe pectus deformity. Many experienced surgeons advocate the use of “sternal elevation techniques” for this part of the operation. This would include the intra-operative use of the vacuum bell device or the Rultract retractor. The second critical step of the operation is determining if more than one bar is necessary for the repair. In recent years, most surgeons have adopted the use of two or even three bars for the correction of the caved in deformity of the sternum. It seems that more than one bar aids in providing better stability to the bar and it also improves the cosmetic correction of the pectus. This is particularly true in older teenagers and young adults that have less pliable chest walls. The third critical step is assuring that the pectus bar is properly stabilized in order to prevent the occurrence of bar displacement. This would include the use of lateral stabilizers and third-point of fixation technique in which the bar is secured with peri-costal sutures (around the bar and around a rib). Bar displacement was reported as the most common complication after surgery in the early 2000’s; today, bar displacement requiring re-operation is considered rare and reported in less than 2.5% of cases when proper bar fixation techniques are employed.
Author
Andre Hebra, M.D.
References
Hebra et al. J Pediatr Surg. 2017
Hebra et al. Eur J Pediatr Surg. 2018; Evr J Pediatr Surg. 2018
Jaroszewski et al. European J Cardiothorac Surg. 2017
Haecker et al. J Pediatr Surg. 2021