The following are answers to some of the most frequently asked questions about corrective surgery for pectus excavatum using the minimally invasive technique (also known as the Nuss Operation or MIRPE):
How does the minimally-invasive approach differ from the old surgical repair?
The minimally-invasive operation for repair of Pectus Excavatum (MIRPE), also known as the Nuss operation, is a completely different surgery from what it used to be. The open Ravitch operation required making an incision in the anterior chest - the front of the chest - and then removing segments of all the ribs affected by the pectus. The outer layer of the cartilage ribs (perichondrium) were preserved in order to allow the ribs to grow back. The sternum had to be fractured in at least one area to allow for it to be bent in the appropriate position. Complications of the open operation included bleeding, infection, injury to the lungs and pleura, and possible need for placement of chest drains. The end result is rated as very good but it does leave a long scar on the chest.
With the new technique (known as the Nuss operation or the minimally invasive repair (MIRPE)), it is not necessary to create large incisions or to remove/fracture any ribs or cartilage, or sternum. The surgeon is able to approach the chest with small lateral chest wall incisions and, using a special camera (thoracoscope), the surgeon can visualize the inside of the chest so that a stainless steel bar can be placed in order to correct the deformity. Again, this is accomplished without creating a large incision across the anterior chest, without breaking bones, and without removing any cartilage. The duration of the entire operation is much shorter. With the open repair, the operation may take 4 to 5 hrs, whereas the Nuss technique is typically completed in just about an hour.
What type of patient should be considered for this operation? What are the indications for surgery?
Patients must be carefully evaluated prior to surgery. The things that we look for are:
- how severe is the deformity (one must determine the chest/”Haller” index)
- what kind of physiologic impairment it is causing to the patient
- what is the psychosocial impact of the deformity
What is the chest index?
The chest index is a measurement taken on the CT scan of the chest in which a ratio is obtained between the lateral and anterior-posterior diameter of the chest wall. A normal chest index is 2.5. Patients with an index greater than 3.2 have a fairly pronounced and severe pectus excavatum and are typically operative candidates. Even if asymptomatic, those patients usually benefit from the corrective surgery.
Is this a cosmetic operation?
Many patients with mild to moderate pectus excavatum will not report any signiâcant shortness of breath. However, upon further questioning, one may ând that the child can't keep up with their peers in the same physical activities that they used to, and/or they tire more easily. It is also not uncommon to see children with pectus excavatum avoid taking their shirt off around their peers, whether in the gym locker room or when participating in outdoor activities, such as going to the beach or pool. Surgical correction can be very beneâcial from a body image standpoint during a crucial time of development.
A parallel comparison can be made with children born with Cleft Lip & Palate - that repair could be considered a cosmetic repair. However, no one would allow a child to go on in life with a cleft lip deformity. Pectus deformity is no different. The only difference is that you can hide a chest wall deformity under clothing. Pectus excavatum is still a deformity of the sternum and the chest that deserves to be corrected if it is causing signiâcant concerns to the patient & family.
Is there an ideal age group for the new operation?
The ideal age for the minimally invasive operation is between 8-14 years. The main reason for that is that the child should be old enough to understand what's ahead, to understand reasons for surgery, and to understand what's involved during the postoperative recovery. Moreover, between 8-12 years of age, the ribs and cartilage are still soft enough and malleable that the chest deformity can be easily repaired with the bar and induce less pain. The recovery from surgery at that age is much easier than it is for teenagers. However, age by itself is not considered a contraindication for surgery.
How does this minimally-invasive procedure work?
The Nuss technique is done through two small lateral chest wall incisions – one on each side of the chest, lateral to the nipple area. A small 5 mm camera is also inserted into the chest, which allows the surgeon to have direct visualization of the placement of the bar and all the important structures inside the chest (such as the heart, blood vessels, and lungs). The surgeon will know exactly where to place the bar. Through these small lateral chest wall incisions, a special curved stainless steel bar (also known as the LORENZ pectus bar) is passed behind the sternum.
The bar comes in different lengths according to age and patient size. The appropriately sized bar is selected at the time of surgery and is bent by the surgeon after certain measurements of the chest are taken. The bar will have a smooth concave shape to it in order to allow for its placement behind the sternum. The bar is passed through the small lateral chest wall incision, under the sternum, in front of the heart, all the way to the other side of the chest. The bar is then flipped, such that the sternum is raised and the entire chest wall is remodeled. The entire maneuver is done under thoracoscopic visualization.
The Nuss technique/MIRPE is essentially comparable to placing an internal "brace" in the chest. The brace (pectus bar) will displace the ribs and the sternum forward, keeping it in that position until complete remodeling of the chest wall has occurred. This process typically takes three years, and for that reason, the bar is left in place for three years.
What holds the pectus bar in place?
The bar is kept in secure position by sutures that attach it to the chest wall muscle fascia. In addition, a lateral stabilizer (a type of T-connector) is attached to one or both sides of the bar for extra points of fixation. Finally, a third point of fixation (an extra stitch that is placed around a rib and around the bar itself) can be used to hold it in place right next to the sternum.
What kind of anesthesia is used? Is it painful?
The operation is done under general anesthesia. In addition, a thoracic epidural is typically standard procedure. The thoracic epidural requires the placement of a catheter in the epidural space (mid-back) by the anesthesiologist. The epidural catheter can remain in place for several days after surgery, allowing doctors from the pain team to deliver certain types of pain medications to facilitate the management of pain & discomfort after surgery. The medications will have a numbing effect, so that the child is essentially numb and with minimal pain from about the nipple level down.
It is important to remember that anytime a patient receives a thoracic epidural, it will be necessary to place a Foley catheter, which is a catheter to drain the bladder. Those patients who have an epidural in place will have trouble voiding, and a Foley will allow for urination into a bag. Once the epidural is removed, the Foley catheter is removed as well.
Patients typically will be discharged home with oral pain medications, including narcotics such as Lortab, Tylenol withCodeine or Oxycodone for 1-2 weeks. This is in addition to an anti-inflammatory medication (like Motrin, Aleve or Advil) and at times mild muscle relaxers.
How long will the bar stay in place? When and how is it removed?
The bar stays in place for about 3 years and most studies have shown that this will give the chest enough time to remodel itself and assume a new "normal" shape, with a low risk of recurrence of the excavatum.
The operation for bar removal is relatively simple. It is usually done as an outpatient procedure, however, it does require general anesthesia. The surgeon will reopen one or two of the small lateral incisions and essentially pull the bar out and close the incision(s) with dissolvable stitches. This procedure typically takes less than 30 minutes, and patients are usually discharged to home shortly thereafter.
Are there common problems or complications associated with this procedure?
The most common problems and complications related to surgery have changed since the operation was first reported in 1996. As the technique has improved, the complication rate has dramatically decreased. For instance, bar displacement, which was reported in almost 10% of the patents, is now reported in about 1%. Other problems such as infection and pneumothorax are very rare. The use of thoracoscopy has also helped in making this a safer operation.
What about uncommon or rare problems?
Occasionally we may see patients that have an initial excellent cosmetic result but the chest may undergo changes without any inciting trauma, affecting the overall appearance of the chest, but not the sternum per se. Some patients may experience different growth rate of the ribs on the left and right side of the chest (this is particularly a concern in patients with severe asymmetry of the chest prior to any corrective surgery). It has been reported before that ribs and cartilage can grow in an unusual way that you didn't expect. This may result in an asymmetric appearance of the chest even after a successful operation using the minimally invasive technique. Unfortunately the surgeon cannot control the rate of bone and cartilage growth in a developing child.
How long does the patient stay in the hospital after surgery?
Immediately after surgery, the patient is taken to the recovery room and then to a general care floor in the hospital. Usually there is no need for critical care monitoring or ICU admission. The room is fairly typical for most hospitals; nurses come in and check on the patient frequently. Other services that will be involved in the patient's care include the pain management, child life, and physical & occupational therapy.
All providers will concentrate speciâcally on the needs of the pectus repair patients.
The average length of stay is on average 5 days. As a rule, the younger child will stay less and the older child and young adults will stay longer. Again, if the ribs are soft and the repair is very easy, odds are that the patent will stay in the hospital just a few days.
Patients and families are advised to pick an ideal time to have the surgery performed. This is usually during the summer when school is out, due to the hospitalization and postoperative recovery time. The recovery period warrants close parental observation and assistance with activities of daily living, due to postoperative pain and the medications that are used to treat it, which is on average 3-4 weeks. Physical activities will be limited, such as carrying a heavy book bag and participating in PE, which makes the summer an ideal time to undergo surgery. It is not uncommon, however, for patients to have surgery during Spring or Christmas breaks, with the possibility of having to be on Home Bound status with school briefly.
Are there limitations after surgery?
Patients are instructed not to lift more than about 10 pounds after surgery, which, as most parents know, is lighter than the average book bag these days. Also, patients can't return to either PE or sports until cleared by their surgeon. Typically patients are seen back in the surgeon's office 2 weeks after discharge from the hospital and, at that time, it is determined, based on the individual patient's progress, when they can go back to physical activities. Generally speaking, most patients will return to sports and normal physical activities 4 - 6 weeks after surgery. Contact sports, which include soccer and football, however, should be avoided for the duration of the bar(3 years).
Despite such initial restrictions, after approximately 4 - 6 weeks, the patient should be fully recovered and should become very, very active. It is important to build up muscle and to regain strength. Thus patients should be participating in sports, running, swimming, biking, and especially weightlifting. It is desirable that children recovering from pectus surgery should build their pectoralis (chest), deltoid (shoulder), and abdominal muscles. Working out with weights is very important after cleared by the surgeon.