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Tracheotomy is a serious procedure in infants and children. It is well established that the morbidity and mortality rate of tracheotomy in the pediatric population is twice that of adults. This presentation serves to provide an overview of the current technique and management of pediatric tracheotomies.
The first tracheotomy was performed in Rome in second century B.C. Antyllus, in second century A.D., further refined the technique by suggesting that the trachea be divided at the third and fourth tracheal rings using a transverse incision. In 1620, Habicot performed the first pediatric tracheotomy. The procedure was performed on a sixteen year old boy who had swallowed a bag of gold in an attempt to keep the gold from being stolen. The bag became lodged in the boy's esophagus and obstructed his trachea. After Habicot performed the tracheotomy, he manipulated the bag of gold so that it would pass. It was eventually recovered per rectum. In 1825, Bretonneu reported a successful tracheotomy on a five year old girl with diphtheria. Afterwards, Trousseau reported performing tracheotomies on over 200 children with diphtheria. He also stressed the importance of post-operative care. Throughout the 1800's, tracheotomies became increasingly popular but the mortality and morbidity of the procedure remained high. In the early 1900's, Chevalier Jackson standardized the procedure and demonstrated that the mortality rate was significantly reduced if the procedure was performed properly and careful attention was paid to post-operative care.(1)
Not until the 1900's was tracheotomy performed for any other reason than upper airway obstruction. Today, there are three basic indications for a tracheotomy in a pediatric patient: 1) upper airway obstruction 2) assisted ventilation 3) pulmonary toilet.
Controversy persists on whether to perform a tracheotomy or endotracheal intubation and when the intervention should take place. A number of factors must be considered. These include the predicted course of the patient's illness, the skill of the physician performing the procedure, and the personnel and equipment available. With the pediatric patient, an additional factor to consider is concerned and frightened parents.
Obviously, each case must be individualized. Some guidelines to the decision making process includes general factors such as those suggested by Stool and Eavey(1); tissue, time and team. Tissue refers to the age of the patient and etiology of the disease process. Younger children have smaller airways, therefore less edema is required to lead to obstruction. In addition, younger children tire more easily than older children or adults. Time refers to the course of the disease process. Does it appear or is it known to be rapidly or slowly progressive? The time factor also includes the condition of the child at presentation. If the child is stuporous, retracting and cyanotic then the decision to intervene is obvious. The team factor refers to the experience of the physician and personnel available to carry out the procedure. Douglas et al(2) developed a mnemonic TRACHS to help with the decision making process (see below). The goal is an orderly, well-timed procedure with an experienced surgeon and the best personnel and equipment possible.
Fabricus in 1600 suggested the use of a cannula with tracheotomy. The initial design was short and straight. Martin in 1730 recommended the use of an inner cannula on the tracheotomy tube.
There are several different types of tracheotomy tubes available. The ideal tube should be soft, pliable, easy to clean and maintain, and available in a variety of sizes and length. The choice of type and size of the tracheotomy tube should be based on the indication for the tracheotomy. If the tracheotomy is performed for upper airway obstruction, the tube should not fill the entire tracheal lumen. If the indication for tracheotomy is assisted ventilation, the tube should fill more of the tracheal lumen to prevent excessive airleak. In smaller children, cuffed tracheotomy tubes are usually not necessary. In older children, a low-pressure cuffed tube may be required to achieve an adequate seal. The choice of tube size should be determined at the time of surgery by visualizing the size of the child's tracheal lumen. There are a few predictors of the appropriate tube size. These include standardized normals based on the child's age, the size of the endotracheal tube if one is already in place, or the size of rigid bronchoscope if one was used to examine the airway. The critical measurement of tracheotomy tube size is the diameter of the tube. The external diameter determines the size that can be inserted but, more importantly, the inner diameter determines the airway size. Mullins et al(3) studied the airway flow characteristics of tracheotomy tubes and their effect on the work of breathing. They used neonatal, pediatric and adult Shiley tracheotomy tubes.
Mullins' group confirmed previous findings that the work of breathing decreases as the inner diameter of the tube increases. They compared the pediatric tube 00 with the neonatal tube 00. Both tubes have the same inner and outer diameter but they differ in length. The measured resistance of the pediatric tracheotomy tubes were greater than the shorter neonatal tubes since the pressure required to achieve a given flow is directly proportional to length. Mullins' group found that the tube most closely resembling the airway resistance of the neonate was the neonatal 0. In contrast to the Shiley size recommendations chart, Mullins found that in children ages 3-7, the pediatric tube that is best is the pediatric tube 3. For children ages 6-11, the pediatric tube that resembles the airway resistance in this age group is the pediatric 4. The adult size 8 most closely approximated the airway resistance of children eleven and older.
Fortunately, Shiley has begun to classify the size of their pediatric and neonatal tubes based on the actual inner diameter. In infants and children, the tracheotomy tubes are shaved inferiorly to prevent erosion on the skin below the tracheostomy.
Communication between the otolaryngologist and anesthesiologist is essential when faced with a child with a compromised airway. It is preferable to perform a tracheotomy with the child under general anesthesia and an endotracheal tube or bronchoscope in place. The procedure usually begins by oxygenating the child in a comfortable position, establishing I.V. access and initiating an anesthetic inhalation agent. The otolaryngologist should be aware at all times what medications the anesthesiologist plans to administer. Muscle relaxants can be used with caution only after it has been established that the child can be ventilated by bag mask. It is essential that the anesthesiologist and otolaryngologist agree on the course of induction. The surgeon should always be prepared to perform rapid rigid bronchoscopy or emergency tracheotomy if direct visualization of the larynx with a laryngoscope is not possible.
As previously stated, general anesthesia with an endotracheal tube or bronchoscope is preferable. The surgeon should position the child him or herself. The neck is hyperextended by placement of a shoulder roll. It is best if the anesthesiologist holds the child’s chin to stabilize the tissues and to keep the neck hyperextended. In infants, all esophageal tubing (nasogastric tubes and esophageal stethoscopes) should be removed to aid in correct identification of the trachea by palpation. The neck is prepped and draped in the usual fashion but the face should be left uncovered. The thyroid and cricoid cartilages are then identified by palpation. This can be very difficult in a young child because the larynx is soft and located in a more superior position when compared with an adult. Important landmarks such as the thyroid and cricoid cartilages, suprasternal notch and planned skin incision are marked. Local anesthetic (0.5% lidocaine with 1:200,000 epinephrine) is used for local injection at the proposed skin incision. The skin incision is made one fingerbreadth above the suprasternal notch. Either a vertical or horizontal skin incision may be used. The incision is carried through the subcutaneous tissues. The trachea is palpated repeatedly during the procedure. Some say that tracheotomy is as much done by palpation as by visualization. Identify the anterior jugular veins and strap muscles.
It is usually not necessary to ligate the anterior jugular veins. The fascia of the strap muscles is grasped on each side of the midline with hemostats. The fascia is lifted, divided with scissors in the midline and slightly undermined. The trachea is again palpated to insure its location. Retractors can be used to gently retract the strap muscles laterally. The thyroid gland can be retracted if necessary. Rarely does the thyroid isthmus need to be divided in a child. If this is necessary, the isthmus should be clamped, divided and suture ligated. Once the trachea is visualized, stay sutures (4.0 Neurolen) are placed bilaterally approximately 2mm from the midline around at least two tracheal rings. This allows the trachea to be delivered into the wound. Hemostasis is then assured. Controversy remains over the type of tracheal incision. The consensus appears to be that a vertical tracheal incision is preferred. The incision is made in the midline of the second, third, and/or fourth tracheal rings. No cartilage should be removed. The tracheotomy tube is inserted after applying anterolateral traction on the stay sutures. The tube is held in place while the shoulder roll is removed. The chest is auscultated for bilateral equal breath sounds. The neck is then slightly flexed and the tracheostomy ties are secured around the neck allowing for one finger to pass underneath the ties. The stay sutures are then secured to the neck with tape printed with "do not remove". A chest x-ray should be obtained post-operatively to insure proper placement of the tracheostomy tube.
Fry et al(4) compared three standard pediatric tracheotomy incisions: 1) inferiorly based trapdoor 2) vertical slit and 3) horizontal H. Using a young animal model ( 8-9 week old ferret), they evaluated the three groups for tracheal stenosis using endoscopy, radiography, and computer-analyzed airflow studies. On endoscopy, they found fairly predicable patterns of tracheal stenosis with each type. The inferior based flap group left an anterior shelf deformity while both the vertical slit and horizontal H groups created an hourglass pattern with lateral narrowing. Airflow studies revealed no difference in airflow resistance in the vertical slit group as compared with controls. In contrast, the horizontal H and inferior trap door groups both had significant (p < 0.05) increases in airflow resistance as compared with controls. Fry's group concluded that the vertical tracheal incision is the best choice in the pediatric patient.
Again, it is preferable to perform a tracheotomy on an adult or a child in a controlled fashion. This, unfortunately, is not always the case. In a child, it is especially difficult to perform a cricothyrotomy because of the very small size of the membrane and difficulty in palpating the structures. Some authors have suggested using a large-bore needle transtracheally, but this too is very difficult due to the flexibility of the child's larynx and trachea. Basically, in a life-threatening situation, any means of obtaining an airway is better than the consequence of not.
The child needs to be monitored in an intensive care setting. A postoperative chest x-ray should be obtained to check tube placement and rule out pneumothorax. Humidified air by collar or ventilator should be provided to prevent excessive dryness and thickness of secretions. Gentle suctioning should be performed every one to two hours the first few days then decreased to as needed. The child may require sedation or restraints to prevent the tracheostomy tube from being accidentally dislodged. The patient can have a diet the following day. Generally, the first tracheostomy tube change is done by the surgeon around postoperative day number five or seven after a good tract has formed. A suction catheter placed through the old tracheostomy tube can be used as a guide for the new tube to be inserted. The stay sutures can also be removed at this time.
The complication rate of pediatric tracheotomy appears to be around 40 %. Complications include operative and postoperative, both early and late. Operative complications include hemorrhage, air entry, anatomic damage, tracheotomy tube problems, respiratory drive cessation and pulmonary edema. Postoperative difficulties can include hemorrhage, air entry, tracheal lesions, tracheostomy tube problems, infection, swallowing difficulties, and aphonia.
Wetmore et al(5) review pediatric tracheotomy over a ten year period. They found that accidental decannulation (24%) was the most common early postoperative complication followed by pneumonia (20%), pneumothorax (9%), subcutaneous air (9%) and obstructed tube(7%). As far as late complications, they found that a tracheo-cutaneous fistula was most common (19%) followed by accidental decannulation (18%), tracheal granuloma (14%), stomal granulation (11%), and obstructed tube (10%).
This complication may be due to a hereditary coagulation defect or an acquired abnormality from liver disease, sepsis or deficient clotting factors in a neonate. The surgeon should be aware of the potential for vascular anomalies. Most bleeding is due to oozing from capillaries and should respond to electrocautery or cease spontaneously.
Air can sometimes dissect between the deep and superficial cervical fascia into the mediastinum. Pneumothorax can occur if the pleura of the lung apex is damaged. Leaving the skin incision open and careful dissection of the pretracheal fascia staying in the midline will help prevent this complication.
Structures in infants and children are quite small and careful attention to dissection is fundamental. Too deep dissection through the posterior tracheal wall can cause injury to the esophagus. Dissection too laterally can injure the recurrent nerves or the carotid. Again, midline dissection can help prevent this complication as well as using a vertical tracheal incision.
The tracheostomy tube may be accidentally dislodged or lead to high airway resistance if the chosen tube is too small. Too large a tube can cause damage from excessive pressure to the tracheal walls. Proper choice of the size of the tracheostomy tube will help avoid these complications. Cannulation of a mainstem bronchus or creation of a false passage may also occur.
This phenomenon has been attributed to loss of ventilatory drive due to rapid change in CO2 tension leading to arrhythmias and hypotension.
Thought to be due to rapid influx of fluid across the alveolar wall because of the sudden change in airway pressure following tracheotomy.
Bleeding from a tracheotomy, especially in the late postoperative period, may herald a serious complication. Tracheal wall erosion can occur from pressure from the tracheostomy tube on the anterior trachea. The innominate artery crosses anterior to the trachea at the superior thoracic inlet. Erosion into this vessel can lead to massive hemorrhage. Direct visualization of the trachea is necessary to rule out this potentially fatal complication. Fortunately, most bleeding postoperatively is secondary to inflammation from excessive drying and suctioning.
Pneumothorax can be caused by high ventilator pressures or aggressive bagging.
Many factors can contribute to damage to the trachea after tracheotomy. This damage can range from tracheal stenosis to granuloma formation. Most authors agree that proper care of the tracheostomy and choosing the appropriate size tracheostomy tube can greatly diminish this complication. Subglottic stenosis can be prevented by avoiding a high tracheotomy. Tracheal granulomas usually occur at the superior lip of the tracheostomy site. They can be treated with observation if small but if large they may need to be removed surgically to avoid stomal obstruction during tube change.
Tracheostomy tube occlusion by crusts and mucous plugs is a common early complication. This can be prevented by humidification and adequate suctioning.
Tracheitis and stomal infections can occur and usually respond to local care, humidified air and suctioning. Cultures can be done if symptoms persist. Pseudomonas and staphylococcus organisms are commonly seen.
As with adults, a tracheotomy tube can interfere with swallowing by inhibiting laryngeal elevation and compressing the esophagus.
Scarring develops whether a horizontal incision or vertical incision is used. A persistent tracheocutaneous fistula can develop and is dependent on the duration of the tracheostomy. It is recommended that if a tracheocutaneous fistula persists for greater than 6-12 months, the entire tract be excised and a multilayered closure be performed. A drain should be inserted to prevent air tracking.
The inability to communicate immediately after a tracheotomy is a very frightening thing for a child. Parents and nursing staff should be alert to the child's inability to clearly communicate distress. If a long term tracheotomy is planned, speech development must be addressed. If the child is decannulated prior to one year of age (pre-lingually) or the child can phonate around the tube, speech development is usually not a problem. If a child is speaking prior to tracheotomy, he or she is at risk for significant expressive delay and the assistance of a speech therapist is essential. The therapist will be able to help develop oromotor skills, maximize receptive language, and encourage non-vocal behavior.
Decannulation of a patient with a tracheotomy is primarily dependent on the original indication for the procedure. Once the underlying pathologic condition has improved and the tracheostomy if felt to be no longer necessary, steps toward decannulation can be initiated. Mallory et al(6) studied whether tidal flow measurements would be a helpful predictor of successful decannulation in the pediatric patient. His group studied forty four children with tracheotomies who were being considered for decannulation. All of the children underwent pulmonary function testing prior to endoscopy. Their maximal inspiratory flow through the mouth (MIFm) and maximum inspiratory flow through the tracheostomy cannula (MIFt) and their ratio (MIFm/MIFt) were measured. A ratio of MIFm to MIFt in liters per second greater than or equal to one was considered favorable for decannulation. Mallory found the predictability ratio of MIFm/MIFt for successful decannulation to be 76% and a false negative ratio of 24% (deemed unfavorable for decannulation but decannulation successful). Endoscopy had a predictability ratio of 84%. Mallory concluded that, although endoscopy remains the most sensitive indicator of successful decannulation, Pulmonary function testing is non-invasive and can be done on an outpatient basis. He developed a decannulation algorithm with PF testing as an adjunct in the decision making process.
Prior to decannulation, the airway should be studied endoscopically to assess the original pathologic condition as well as look for possible new problems caused by the tracheostomy. Any tracheal or stomal granulomas should be excised. Vocal cord motion should be assessed.
Sasaki et al(7) studied decannulation failures and found that 25% were caused by temporary abductor failure. The pathophysiology behind this appears to be an abrupt increase in dead space and airway resistance upon removal of the tracheostomy tube. Gradually decreasing the size of the tracheostomy tube seems to allow for return of abductor movement.
A trial of tracheostomy tube plugging should be performed prior to decannulation. The tube should only be plugged during the day when an adult is present if the child is not hospitalized. Just prior to decannulation, an overnight admission to a monitored hospital bed is required for night time plugging. After decannulation, a light pressure dressing should be applied. Once decannulated, the child should continue to be monitored for 24-48 hours in the hospital.
Not all patients can be decannulated and require their tracheostomies long-term. The majority of these patients can receive care of their tracheostomies at home. The families are usually frightened and apprehensive about taking their child home and assuming care for them. Therefore, parent and family education and discharge planning is critical. This requires considerable coordination and communication between the family and a number of health care workers.
Prior to discharging a child home with a tracheostomy, the parents have to demonstrate proficiency in the use of the equipment needed, nursing care of the tracheostomy, detection of problems and emergency care. They should be taught CPR for a child with a tracheostomy. Ideally, this should occur in the hospital setting with the parents assuming total care of the child for a couple of days prior to discharge. Videotapes are available for viewing as well as trachestomy manuals for use as a quick reference. A responsible adult must be with the child at all times. It is a good idea to arrange for home health to evaluate the home and make sure all equipment is functional. It is important to notify the electric and telephone companies that a child with a tracheostomy lives in the home and service cannot be interrupted for any reason. The EMS service should also be informed. The child should be followed up by a tracheostomy team if available as well as their primary pediatrician.
In regard to tube sizing, the new Shiley tubes now are named by number corresponding to the inner diameter. Bivona tubes also have a good numbering system.
All the caretakers of a child should be aware of the indication for the tracheotomy and whether the airway is patent or obstructed. Also resuscitation plans should be known by all caretakers including hospital personnel when the child is in the hospital which would help in resuscitation should the tube become obstructed or accidentally displaced without the ability to replace the tube. For instance, bag and mask or intubation from above would be possible in some airways and in other obstructed airways immediate replacement of the tube through the stoma would be required.
1) Stool SE and Eavey R. Tracheotomy. In: Bluestone and Stool, ed. Pediatric Otolaryngology.W.B. Saunders, Philadelphia, 1983.
2) Douglas GS, Hoskins D, and Stool SE. Tracheotomy in Pediatric Airway management. ENT J. 1978;57:55-70.
3) Mullins JB, et al. Airway Resistance and Work of Breathing in Tracheostomy Tubes. Laryngoscope. 1993;103:1367-1372.
4) Fry TL, Fischer ND, Jones RO, Pillsbury HC. Comparisons of Tracheostomy Incisions in a Pediatric Model. Ann Otol Rhinol Laryngol. 1985;94:450-453.
5) Wetmore RF, Handler SD, Postic WP. Pediatric Tracheostomy. Experience During the Past Decade. Ann Otol Rhinol Laryngol. 1982;91:628-632.
6) Mallory GB, et al. Tidal Flow Measurement in the Decision to Decannulate the Pediatric Patient. Ann Otol Rhinol Larygol. 1985;94:454-457.
7) Deskin RW. Pediatric Tracheotomy. In press.
8) Weissler MC. Tracheotomy and Intubation. In: Bailey BJ, et al , eds. Head and Neck Surgery-Otolaryngology. Philadelphia: J.B. Lippencott, 1993.
9) Ruben RJ, et al. Home Care of the Pediatric Patient with a Tracheotomy. Ann Otol Rhinol Laryngol. 1982;91:633-640.
10) Hazinski MF. Pediatric Home Tracheostomy Care: A Parent's Guide. Pediatric Nursing. 1986;12:41-47.