In this chapter we review plastic surgery procedures that pose a wide range of perioperative challenges for the anesthesiologist, including difficult airway management, significant intraoperative blood loss, and comorbidities secondary to an underlying genetic syndrome. We also review considerations for subcutaneous administration of epinephrine.
Craniofacial Anomalies
The Committee on Nomenclature and Classification of Craniofacial Anomalies of the American Cleft Palate Association has organized facial anomalies into five categories: cleft, synostosis, hypoplasia, hyperplasia, and unclassified. Each of these categories of craniofacial anomalies are potentially associated with difficult airway management.
Clefts can involve the lip, palate, or both. Craniosynostosis occurs when there is premature closure of one or more cranial sutures. Some of the most common craniosynostosis syndromes include Apert, Pfeiffer, Crouzon, Saethre-Chotzen, Carpenter, and Muenke syndromes, and all are associated with difficult intubation. Examples of syndromes associated with craniofacial hypoplasia include Pierre Robin sequence and Goldenhar syndrome. Ease of intubation tends to improve with age in children with hypoplastic craniofacial dysmorphisms. Mucopolysaccharidoses, including Hunter and Hurler syndromes and vascular malformations, are examples of hyperplastic anomalies.
Cleft Lip Repair
A cleft lip is a unilateral or bilateral split of the upper lip between the mouth and nose. It can range from a slight notch to a complete separation of one or both sides of the lip extending up and into the nose and is often accompanied by a cleft palate ( Fig. 28.1 ). The overall incidence of cleft lip is approximately 1 in 800 live births. Although the majority of cleft lips are not associated with any predisposing factors, a history of maternal smoking or phenytoin use increases the risk. Associated defects such as congenital heart disease occur in approximately 10% of affected children. Feeding difficulties in the newborn period may lead to poor growth and anemia. Surgical repair is usually performed at 3 to 6 months; some centers are correcting these lesions in the first 30 days of life with findings that high levels of estrogen found in neonates aid in the surgical repair and recovery. Older children may return for subsequent cosmetic repairs of the lip or nasal tip.
In infants with cleft lip/palate as an isolated defect, preoperative evaluation and intraoperative management is no different from that for other healthy infants undergoing elective procedures. Because cleft lip repair is often performed around 3 months of age, a preoperative hemoglobin level may be checked as this coincides with the physiologic nadir of infancy.
A mask induction of general anesthesia is most often performed, followed by endotracheal intubation with an oral Ring, Adair, and Elwyn (RAE) endotracheal tube. Special care must be taken in selecting the proper size oral RAE tube, as the location of the preformed bend on these tubes varies according to the tube size. The patient’s eyes may be protected with ophthalmic ointment and covered by a transparent adhesive covering to preserve visible surgical landmarks. The operating room (OR) table is turned 90 degrees away from the anesthesia provider to facilitate surgical repair from the head or side of the table. A small amount (usually <1 mL) of local anesthetic with epinephrine is injected into the surgical field to facilitate hemostasis at the incision site. Blood and fluid losses are minimal. Therefore, maintenance and preoperative deficit fluid replacement is sufficient. A small amount of opioid may be administered intraoperatively. The intravenous (IV) administration of acetaminophen may also be helpful to decrease opioid requirements. Bilateral soft arm restraints are used to keep the infant from handling the repair postoperatively.
Some pediatric anesthesiologists advocate regional anesthesia for cleft lip repair. An infraorbital nerve block with a long-acting local anesthetic can provide up to 18 hours of pain relief and decrease postoperative administration of opioids.
Cleft Palate Repair
A cleft palate occurs when the roof of the mouth (i.e., hard and/or soft palate) has not unified completely during fetal development. A cleft palate can range from a small bifid uvula to a complete separation of both the soft and hard palate. Associated congenital defects occur in up to 50% of infants born with a cleft palate. The velocardiofacial syndrome, also known as DiGeorge syndrome , is the most common syndrome associated with a cleft palate. About 1 in 3000 children per year are born with it. Cleft palate can also exist as a component of the Pierre Robin sequence (triad of cleft palate, glossoptosis, and micrognathia). Early concerns in the newborn period relate to feeding difficulties and airway compromise.
In children with cleft palate and upper airway obstruction caused by micrognathia and glossoptosis, mild cases of obstruction can often be managed by prone positioning. In more severe cases, life-threatening upper airway obstruction may result, mandating surgical intervention. Surgical options in these cases include glossopexy (tongue-lip adhesion, to prevent glossoptosis), mandibular osteotomies and placement of distractor hardware (to elongate the mandible via distraction osteogenesis), and tracheostomy. These procedures are typically done early in infancy, months before the palatoplasty is performed.
Surgical correction of cleft palate is usually performed at 9 to 12 months of age. Older children may present for subsequent procedures such as correction of velopharyngeal incompetence, or repair of residual palatal defects with a bone graft. If a child is born with both cleft lip and cleft palate, the lip repair is performed first because the repaired lip helps decrease the expanding width of the palatal defect as the infant grows. Repairing the lip defect also facilitates bottle feeding using a specially molded nipple.
Preoperative considerations for children presenting for cleft palate repair are focused on delineation of coexisting medical problems and assessment of airway patency. Infants older than about 9 months of age and without airway compromise are candidates for anxiolytic premedication. Unless intravenous access is previously established, inhaled induction of general anesthesia is performed. Upper airway obstruction during this phase is common and is often relieved by placement of an oral airway to prevent the tongue from becoming lodged in the cleft. Endotracheal intubation by direct laryngoscopy may be complicated by the presence of micrognathia or unintentional placement of the laryngoscope blade into the cleft during laryngoscopy. Some pediatric anesthesiologists prefer to place gauze material into the cleft before laryngoscopy attempts. If this is done, caution must be taken to ensure that the gauze does not become dislodged and cause airway obstruction. An oral RAE tube is inserted and the OR table turned 90 degrees to facilitate surgical repair from behind the head of the infant.
Surgical exposure is achieved by placing the supine infant on a small shoulder roll, extending the neck, and inserting a Dingman retractor into the mouth. Neck extension is associated with cephalad movement of the tracheal tube tip, so proper positioning of the tube should be confirmed after final patient positioning. Care must be taken to avoid pinching the tracheal tube (usually presenting as a sudden increase in airway resistance) during placement of the Dingman retractor. Neck extension may need to be avoided in children with abnormalities of the cervical spine. Local anesthetic containing epinephrine is then infiltrated into the surgical field to facilitate intraoperative hemostasis; typically, the amount injected is well within the calculated toxicity dose limit for these children (discussed at the end of the chapter). Blood and fluid losses are minimal but somewhat greater than for cleft lip repair, and may not always be readily apparent. A throat pack may be placed by the surgeon to absorb blood and prevent it from passing into the esophagus and stomach.
A balanced anesthetic of inhaled and intravenous agents is chosen for maintenance of general anesthesia. The primary concern after emergence from anesthesia and tracheal extubation is the potential for upper airway obstruction caused by surgical closure of the palatal defect combined with soft tissue swelling. A conservative dose of opioids before emergence is prudent, and perioperative dexamethasone is administered to decrease soft tissue edema. Intravenous acetaminophen may be administered to reduce opioid requirements. Before tracheal extubation, the oropharynx should be gently suctioned to remove retained blood and secretions while taking care not to disrupt the delicate suture lines. In some cases, the surgeons will place a loop suture through the anterior portion of the tongue, which can then be pulled anteriorly if the tongue is causing postoperative upper airway obstruction. This suture is then usually removed within several hours after the procedure when the child has demonstrated the ability to maintain airway patency without assistance.
The primary postoperative concerns after cleft palate repair are airway patency and pain control. Prone or lateral positioning is often helpful to alleviate obstruction by the tongue. If indicated, small doses of morphine or hydromorphone are administered while monitoring upper airway patency. Children with the combination of cleft palate and micrognathia (e.g., Pierre Robin sequence) are at increased risk for postoperative airway obstruction after palatoplasty procedures. In these cases, the surgeon may insert a soft nasopharyngeal airway and secure it with a suture during the operation. Placement of an oral airway postoperatively is relatively contraindicated because it may disrupt the surgical repair. A nasal airway or nasotracheal tube is also relatively contraindicated in future anesthetics if a posterior pharyngeal flap was used to repair the cleft. If nasotracheal intubation is needed for a future anesthetic, flexible bronchoscopic guided intubation is necessary for careful guidance of the tracheal tube around the pharyngeal flap because flap damage and subsequent hemorrhage can occur.
Significant postoperative hemorrhage is infrequent but does occur and may initially be unrecognized as the blood may be swallowed. Postoperative hemorrhage requires immediate surgical exploration, and airway management can be challenging because of blood in the airway. Transfusion may be necessary, and restoration of an adequate circulating volume should occur before induction of anesthesia.
Bilateral suprazygomatic maxillary nerve blocks have been shown to decrease postoperative opioid requirements in infants undergoing cleft palate repair and can be performed with the classical landmark technique or with ultrasound guidance.
Craniosynostosis Repair
Types of Craniosynostosis
At birth, the skull consists of distinct cranial bones separated by malleable strips of connective tissue that are known as cranial sutures. During the first 2 years of life, the sutures serve as growth sites for the deposition of additional cranial bone with eventual formation of the adult skull. Primary craniosynostosis, which occurs in approximately 1 in 2000 live births, results when one of these sutures closes prematurely, thus restricting growth of the adjacent cranial bones in a perpendicular direction ( Fig. 28.2A–G ). The remaining cranial bones that are adjacent to normal sutures continue to grow unchecked, producing a misshapen head that may affect facial anatomy, brain structure, and brain function. Elevated intracranial pressure may also occur. Secondary craniosynostosis results from an abnormal progression of brain growth and expansion. Most forms of craniosynostosis are diagnosed in the first several months of life, after the completion of normal cranial molding that is attributed to the birth process.
