A new sternum elevator reduces severe complications during minimally invasive repair of the pectus excavatum

Current Development of Minimally Invasive Repair of Pectus Excavatum (MIRPE)

For decades, open surgical repair was the only available method to treat congenital and acquired chest wall deformities (CWDs). In 1998, D. Nuss described a minimally invasive procedure for surgical repair of Pectus excavatum (PE). Today, the Nuss procedure is performed with increasing frequency worldwide and considered as the “gold standard”. After its introduction, the method experienced numerous modifications such as routine thoracoscopy and/or sternal elevation, increasing safety of the procedure. Placement of multiple bars and/or the so called cross-bar technique were introduced to correct complex CWDs. Standardized pain management, the introduction of cryo-analgesia and a standardized postoperative physiotherapy program including deep breathing exercises facilitate the establishment of an enhanced recovery after surgery (ERAS) process. However, the widespread use of the minimally invasive repair of pectus excavatum (MIRPE) procedure has been associated with a significant number of serious complications. Furthermore, several studies report near-fatal complications, not only during bar placement, but also during bar removal. This review focuses upon the most relevant modifications, including recent published surgical techniques of MIRPE, in order to describe current developments in the field.

Sternal elevation by the crane technique during pectus excavatum repair: A quantitative analysis

Introduction

The crane technique is used to facilitate sternal elevation to provide safe mediastinal passage during the Nuss procedure. The aim was to objectively quantitate the elevation of the crane by 3-dimensional chest images acquired during the Nuss procedure.

Methods

A prospective cohort study was conducted. Patients undergoing the Nuss procedure were eligible. Sternal elevation was achieved by the crane technique providing a simultaneous lift of the anterior chest wall and reduction of the pectus excavatum depth. Both effects were evaluated. Three-dimensional surface images were acquired before incision, following sternal lift, and after bar implantation and quantitatively compared. Reduction of the external pectus excavatum depth was expressed as a percentage.

Results

Thirty patients were included. Ninety percent were male, with a median age of 15.5 years (interquartile range [IQR], 14.5-17.4), Haller index of 3.56 (IQR, 3.09-4.65), and external pectus depth of 18 mm (IQR, 11-23). Sternal elevation by the crane provided a median 78% (IQR, 63-100) reduction of the deformity, corresponding with a residual depth of 3 mm (IQR, 0-7). The percentual reduction diminished with increasing depth of the sternal depression (correlation, –0.86). Besides reducing the deformity, the crane caused an elevation of the anterior chest over a large surface area with a maximum lift of 26 mm (IQR, 19-32).

Conclusions

The crane is an effective sternal elevation technique, providing 78% reduction of the sternal depression, although its effect lessens with increasing depth. In addition, it produces an elevation of the anterior chest over a large surface area.

An Initial 5-Year Single-Center Experience of 365 Patients Undergoing the Video-Assisted Thoracoscopic Surgery for Nuss Procedure for Pectus Excavatum in Resource-Scare Setting

Background: Little is known about video-assisted thoracoscopic surgery in the Nuss procedure (VATS-NUSS) and its postoperative outcomes in the resource-scarce conditions in clinical practice such as Vietnam. Available evidence in the literature was mostly reported from large institutions in developed countries. Hence, this study was conducted to review our initial large single-center experience in the use of the VATS-NUSS for patients with pectus excavatum (PE) within 5 years.

Methods: Data from 365 consecutive PE patients between January 2015 and December 2019 who were surgically treated with VATS-NUSS were retrospectively analyzed.

Results: Of 365 patients, median age at operation was 15.61 ± 3.73 years (range = 5–27 years), most being child and adolescent. Three hundred nine patients (84.65%) were male. PE was commonly detected at puberty (n = 328, 89.9%). Postoperatively, early complications consisted of pneumothorax (n = 5, 1.37%), pleural bleeding/pleural fluid (n = 2, 0.55%), pleural hematoma (n = 1, 0.27%), pneumonia (n = 1, 0.27%), surgical wound infection (n = 1, 0.27%), incision fluid accumulation (n = 3, 0.82%), metal bar infection (n = 1, 0.27%), atelectasis (n = 3, 0.82%), and fever (n = 8, 2.19%). Late complications included surgical wound infection (n = 2, 0.55%), metal bar deviation (n = 5, 1.37%), metal bar allergy (n = 10, 2.74%), recurrent PE (n = 2, 0.55%), and persistent PE (n = 5, 1.37%). No deaths occurred. In 175 patients (47.95%) experiencing bar removal, mean operative time for bar removal was 34.09 ± 10.61 min, and the length of hospitalization following bar removal was 2.4 ± 1.34 days; the most frequent complication was pneumothorax (n = 19, 10.85%). One wound infection and one incision fluid accumulation happened following bar removal. Favorable midterm to long-term postoperative outcomes were achieved.

Conclusions: From the beginning of the Vietnamese surgeons' experience, VATS-NUSS application obtained favorable outcomes with minimizing the occurrence of serious intraoperative and postoperative complications. Current rare evidence enables to give a real picture in the application, modification, and development of VATS-NUSS in the countries having similar resource-scarce conditions.

From bench to bedside: 3D reconstruction and printing as a valuable tool for the chest wall surgeon

BACKGROUND/PURPOSE

The development of computer-aided design/manufacturing and digital image technology shows promise to revolutionize several medical and surgical fields. In this context, we propose a different approach for minimally invasive repair of pectus excavatum (MIRPE) including preoperative planning, ambulatory template fitting, and implant customization.

METHODS

We prospectively collected data on 130 consecutive patients who underwent a novel process of implant customization for MIRPE between November 2015 and September 2019 at our institution. This process consisted of: 1) preoperative planning using 3D computed tomography scan reconstruction and 3D printing of the implant template, 2) an ambulatory fitting session with the template, and 3) manufacture of a custom made, prebent, metallic implant based on the 3D printed templates. We described the process in detail and analyzed the "implant-deformity" match, need for rebending, modification of the curvature or shape of the pectus implant intraoperatively, and accuracy of the number of bars planned preoperatively.

RESULTS

Preoperative planning including 3D reconstruction and printing resulted in a 92.3% optimal "implant-deformity" anatomic match. Minimal rebending without flipping of the implants was required in 5.4% of the patients. In two cases (1.5%), the implants were too short, and they tended to sink into the intercostal space, and in one case (0.8%), the patient's chest was extremely asymmetric, and the implant had to be removed and rebent intraoperatively. The number of implants planned preoperatively was precise in 100%.

CONCLUSIONS

In this study, we demonstrated that minimally invasive repair of pectus excavatum assisted by preoperative planning, ambulatory template fitting, and implant customization enables an excellent anatomic match, leading to minimal rebending, and avoiding implant flipping or removal after retrosternal passage as well as accuracy in the number of bars programmed preoperatively.

TYPE OF STUDY

Prospective registry.

LEVEL OF EVIDENCE

III.

Nuss procedure for pectus excavatum in a patient with cleidocranial dysplasia

Cleidocranial dysplasia is an autosomal skeletal disorder resulting from delayed or abnormal ossification of bony growth. Pectus excavatum independently presented in a 9-year-old boy with cleidocranial dysplasia and was corrected using the Nuss procedure. There were no perioperative complications, and the post-operative course was uneventful. Although there were concerns regarding extraordinary late consolidation or remodeling of the bony thorax, placement of a Nuss plate for 5 years and 6 months improved the patient's concave deformity without re-depression.

Sternal elevation techniques during the minimally invasive repair of pectus excavatum

The aim of the review was to evaluate the routine use of sternal elevation techniques (SETs) during minimally invasive repair of pectus excavatum (MIRPE, the Nuss procedure). We performed a review of the literature between January 1998 and September 2018 with focus on different methods of SET during MIRPE. Reported effects and side effects were evaluated and compared with our own experience concerning the routine use of the vacuum bell for sternal elevation during MIRPE during the last 13 years. SET is more often used in adult patients than in adolescents. SET improves visualization and safety of MIRPE. Advancement of the pectus introducer, retrosternal dissection and placement of the pectus bar are easier. The risk of cardial and/or pericardial lesion is reduced significantly. Different types of retractors, a crane combined with a wire and/or customized hooks are reported to be used as SET. Furthermore, routine use of a subxiphoid incision is reported. However, more technical equipment, and in some SETs additional incisions are necessary. In contrast, no additional skin incision is necessary for the vacuum bell. The routine intraoperative use of the vacuum bell was safe and effective in 131 patients. It facilitates the retrosternal dissection and the insertion of the pectus bar like other SETs. Besides a temporary mild hematoma, no relevant side effect was observed. In conclusion, an increasing number of authors report on the routine use of SET during MIRPE to improve safety of the procedure. We recommend the routine intraoperative use of the vacuum bell during MIRPE.

Culture of safety and error traps in pediatric thoracoscopy

Growing adoption of thoracoscopy by pediatric surgeons has resulted in increasingly complex operations being performed. Although common complications of these procedures have decreased with experience, surgeons are still at risk to fall into error traps where routine practice in uncommon situations results in unanticipated complications. A background culture of safety that rewards multidisciplinary communication, teamwork, openness and standardization of care can assist surgeons to recognize, address and report error traps when they arise. This article serves to encourage a culture of safety and raise awareness of error traps in pediatric thoracoscopy to minimize potential harm and improve quality of care.

Back to the future: a case series of minimally invasive repair of pectus excavatum with regular instruments

OBJECTIVE

Minimally invasive repair of pectus excavatum (MIRPE) is a surgical treatment for PE. During the procedure, a specialized introducer is used to tunnel across the mediastinum for thoracoscopic insertion of a metal bar. There have been reported cases of cardiac perforation during this risky step. The large introducer can be a dangerous lever in unskilled hands. We set out to determine the safety and feasibility of using regular instruments (i.e., not relying on special devices or tools) to create the retrosternal tunnel during MIRPE.

METHODS

This was a preliminary study of MIRPE with regular instruments (MIRPERI), involving 28 patients with PE. We recorded basic patient demographics, chest measurements, and surgical details, as well as intraoperative and postoperative complications.

RESULTS

Patients undergoing MIRPERI had Haller index values ranging from 2.58 to 5.56. No intraoperative complications occurred. Postoperative complications included nausea/vomiting in 8 patients, pruritus in 2, and dizziness in 2, as well as atelectasis, pneumothorax with thoracic drainage, pleural effusion, and dyspnea in 1 patient each.

CONCLUSIONS

In this preliminary study, the rate of complications associated with MIRPERI was comparable to that reported in the literature for MIRPE. The MIRPERI approach has the potential to improve the safety of PE repair, particularly for surgeons that do not have access to certain special instruments or have not been trained in their use.

Nuss procedure for patients with pectus excavatum with a history of intrathoracic surgery

BACKGROUND

The aim of this study was to demonstrate the feasibility and safety of the Nuss procedure for patients with pectus excavatum (PE) with a history of intrathoracic surgery.

PATIENTS

From April 2010 to December 2013, we performed 6 cases of PE repair in patients with a history of intrathoracic surgery. The causes of previous operations were congenital cystic adenomatoid malformation in 4 patients and congenital diaphragmatic hernia in 2. The patients' median age was 5 years (range, 4-9 years) and median preoperative pectus severity index was 4.63 (range, 3.42-10.03). Their intraoperative and postoperative courses were reviewed retrospectively.

RESULTS

The mean overall operation time was 127.5 ± 17.0 minutes, and the mean operation time for endoscopic pneumolysis was 28.8 ± 12.3 minutes. Intraoperative exploration for pleural adhesion revealed that the endoscopic approach in the previous operation was associated with low pleural adhesion, and the open thoracotomy or laparotomy approach was associated with low to high pleural adhesion. One patient developed a pneumothorax on the first postoperative day. All the other patients had uneventful postoperative courses. All the patients received bar removal 2-3 years after bar insertion. One patient developed atelectasis after bar removal. All the other patients had an uneventful postoperative course. The mean postoperative follow-up time after bar removal was 20.1 ± 14.7 months.

CONCLUSIONS

History of intrathoracic surgery seems not a contraindication for the Nuss procedure. However, perioperative complications should be carefully monitored in both the bar insertion and removal operations.

Nuss procedure in the adult population for correction of pectus excavatum

Minimally invasive repair of pectus excavatum has been successfully modified for use in adult patients. Many patients present in adulthood with progression of symptoms as the chest wall becomes less compliant with age. A thorough workup is completed including echocardiogram and chest CT to evaluate for anatomic abnormalities. Cardiopulmonary exercise testing is done to quantify the physiologic impact. Modifications of the original Nuss procedure required to allow for successful adult repair include the use of forced sternal elevation, the use of multiple bars, medial bar fixation, and interspace support to prevent bar rotation and migration. Occasionally, fractures may occur that require an open procedure and osteotomy or cartilage resection and hybrid approach incorporating the principals of intrathoracic support and osteotomy with bar stabilization.

The Vacuum Bell device as a sternal lifter: An immediate effect even with a short time use

BACKGROUND

To minimize cardiac perforation during the minimally invasive repair of pectus excavatum (MIRPE), several surgeons have suggested using a suction device to intraoperatively lift the sternum. Whether or not this technique is effective for all PE patients is not yet known. As such, our aim was to quantify the extent to which a suction device is capable of lifting the sternum with a short duration of use.

METHODS

30 PE patients received a low-dose CT scan as part of standard PE evaluation. A Vacuum Bell suction was then applied for only two minutes, and a repeat CT scan was obtained only at the deepest point of the chest wall deformity. We compared chest dimensions before and after Vacuum Bell suction.

RESULTS

The Vacuum Bell lifted the sternum in all 29 patients included in the analysis. The absolute change in depth ranged from 0.29 to 23.67mm (M=11.02, SD=6.05). The average improvement in Haller index was 0.76. The suction was most effective for individuals with low BMI and smaller chest depths. Efficacy was not associated with gender, age, or chest morphology.

CONCLUSIONS

The Vacuum Bell device effectively lifted the sternum in PE patients with different demographics and chest morphologies. Future research is needed to address whether or not the device reduces risk of cardiac perforation during MIRPE.

LEVELS OF EVIDENCE

Prognosis Study Level IV.

Outcomes in adult pectus excavatum patients undergoing Nuss repair

Pectus excavatum (PEx) is one of the most common congenital chest wall deformities. Depending on the severity, presentation of PEx may range from minor cosmetic issues to disabling cardiopulmonary symptoms. The effect of PEx on adult patients has not been extensively studied. Symptoms may not occur until the patient ages, and they may worsen over the years. More recent publications have implied that PEx may have significant cardiopulmonary implications and repair is of medical benefit. Adults presenting for PEx repair can undergo a successful repair with a minimally invasive "Nuss" approach. Resolution of symptoms, improved quality of life, and satisfying results are reported.

Cardiac arrest without physical cardiac injury during Nuss repair of pectus excavatum

BACKGROUND

Cardiac arrest is a lethal complication of Nuss repair of pectus excavatum which is strongly related to heart or big vessels injury. A rare case developed cardiac arrest without direct cardiac injury during Nuss procedure is presented in this article.

CASE PRESENTATION

In July 2015, a previously healthy 18-year-old man undergoing Nuss repair for pectus excavatum developed cardiac arrest while the Nuss bar was being inserted into the chest. After successful resuscitation and exclusion of direct cardiac injury, the Nuss procedure was continued. The patient suffered a second cardiac arrest during rotation of the Nuss bar. This time, the patient had poor initial response to resuscitation and defibrillation until the retrosternal bar was removed. He ultimately recovered well from the episodes of cardiac arrest, but was unable to receive surgical correction of his pectus excavatum deformity.

CONCLUSIONS

The possible mechanisms of cardiac arrest and lessons we can learn from this complication are discussed.

Minimally invasive repair of pectus excavatum in children: Results of a modified Nuss procedure

INTRODUCTION

Pectus excavatum (PE) is the most common deformity of the anterior thoracic wall. The Nuss technique allows the thorax to be reshaped with the aid of a retrosternal metallic bar. The aim of this study is to evaluate and compare the complication rate between the original Nuss technique and a lightly modified approach.

MATERIAL AND METHOD

We performed a retrospective single-center observational study based on the medical files of patients operated for PE in the Pediatric Surgery Unit between July 2004 and July 2015. We divided two patient groups according to the operating technique employed: the Nuss group (NG) and the modified Nuss group (MNG) with supplementary subxiphoid incision and bilateral thoracoscopy.

RESULTS

Twenty-seven patients were included: sixteen in the NG and eleven in the MNG. No significant differences were found between the two groups for all kinds of complications: total complication rate (50% for the NG versus 54% for the MNG, P>0.05), early (31% vs 46%, P>0.05), late (19% vs 9%, P>0.05), non-serious (37% vs 36%, P>0.05) or serious (13 vs 18%, P>0.05). There was no life threatening complication in the MNG, contrary to the NG. In the two groups, a significant difference was found (P=0.029) regarding the operating time: longer operating times (80±25min) were correlated with a higher complication rate.

CONCLUSION

The modified Nuss technique does not cause more complications than the original technique described by Nuss and it has the advantage to minimize the risk of heart damage.

Usefulness of Kent retractor and lifting hook for Nuss procedure

Although the Nuss procedure for pectus excavatum has been widely employed, a variety of complications have been reported. The most dangerous complication is cardiac injury from the insertion of the introducer. To eliminate these complications, we present a sternum elevating technique using a Kent retractor and a lifting hook.

Technical innovation in minimally invasive repair of pectus excavatum

The aim of study was to introduce technical innovation of MIRPE which reduces the risk of cardiac injury. Modification of MIRPE method with semiflexible thoracoscope and sternum elevating technique has been used. Volkmann bone hook has been inserted percutaneously to the sternum. The hook elevates the sternum forward and enlarges the retrosternal space for safer passage of thoracoscopically guided introducer. Using semiflexible thoracoscope allows better view from various angles via one site of insertion. During the period 2005-2012, the MIRPE was performed on 29 girls and 151 boys; the mean age at the time of surgery was 15.9 years (range 13-18.7 years). The mean Haller index was 4.7 (range 2.7-20.5). The most common complication was pneumothorax (3.3 %) and the incidence of bar displacement was 2 %. The most serious complication was cardiac perforation when inserting Lorenz introducer. This occurred in a 16-year-old girl; she required urgent sternotomy with right atrial repair and recovered well. External elevation of sternum with the hook was used since this case. Subsequent 113 patients underwent surgery without any serious complications. Technical innovation using semiflexible thoracoscope and hook elevation of the sternum reduces the risk of cardiac injury. The hook opens the anterior mediastinum space effectively and makes the following dissection relatively safe and straightforward.