Craniofacial Surgery

Stephen A. Schendel MD, DDS, FACS¹

Richard A. Jaffe MD, PhD²

¹SURGEON

²ANESTHESIOLOGIST

REPAIR OF FACIAL FRACTURES

SURGICAL CONSIDERATIONS

Description: Facial fractures are classified by location and the involved bones.

Upper and midface region: Frontal sinus fractures may involve the anterior wall alone or also may involve the nasofrontal ducts and/or posterior wall. Nasofrontal duct disruption may require obliteration of the duct and sinus, which is done with an electric burr and loupe magnification to remove all mucosa before grafting the area with bone, fat, or pericranium. A posterior wall disruption is a fracture into the anterior cranial fossa that may require CSF leak repair ± cranialization of the sinus (complete removal of the posterior wall of the sinus). Each frontal bone forms a large component of the orbital roof, and as such, ocular injury or periorbital entrapment must be considered.

Fractures of the maxilla are classified as LeFort I, II, or III, depending on the level of the fracture (Fig. 11.3-2). Le-Fort I is a horizontal fracture, separating the teeth and lower maxillary components from the upper facial structures. LeFort II is a triangular fracture with a fracture line across the nose, below the infraorbital rims, and extending through the entire lower maxillary structures. LeFort III is essentially a disassociation of the cranium and face. In these cases, the maxilla is usually mobile or impacted posteriorly and occasionally closes off the posterior airway. Further mobility of the segments may be present with a sagittal split of the palate. Associated fractures in the maxillary region include fractures of the zygoma, orbital fractures (most commonly orbital floor), isolated nasal fractures, naso-orbital-ethmoid (NOE) fractures (usually with severe comminution of the upper face), and cranial base fractures with the potential for dural tears and CSF rhinorrhea. Added procedures which may be required to complete the repair of these fractures include local flap closure of a CSF leak and primary bone grafting, usually from cranium or distant sites, such as the ilium, to highly comminuted areas (e.g., NOE, orbital floors).

Lower face: Fractures of the mandible are classified by the type of fracture and location (Fig. 11.3-3), the most common being the subcondylar fracture. Fractures involving the mandibular body, such as a parasymphyseal fracture, may result in unstable mandibular segments. In cases of bilateral mandibular body fractures associated with symphyseal fractures, the mandible can be flail and fall posteriorly in the supine position, allowing the tongue to block off the airway. All of the fractures involving change in occlusion (LeFort maxillary and all mandibular fractures) require reestablishment of a normal occlusion by the application of arch bars and wires also called intermaxillary fixation (IMF). This may be combined with rigid fixation, most commonly internal plates. In some cases, rigid fixation will allow removal of the IMF at the end of the case; in others, IMF may be required for postop healing. Removal of the throat pack prior to final IMF is of paramount importance.

Trismus may be associated with any of the above injuries 2° direct injury to the muscles of mastication but is more commonly associated with fractures of these muscular attachments (e.g., mandible, zygoma). Associated dentoalveolar fractures of the maxilla or mandible may require preop wiring in the ER. The intent is to hold steady those segments with tenuous stability and blood supply. Intubation techniques should avoid displacing these segments. Fractures not involving change in occlusion (e.g., orbital zygomatic, nasal fracture) can be orally intubated. Most fractures with a change in occlusion should be nasally intubated with RAE or 60° curved connector. Exceptions include edentulous segments allowing tube to pass versus edentulous patient with a splint fabricated for oral intubation. Another preop consideration is the amount of blood loss at the scene or in the ER. Facial and scalp vessels can bleed profusely (hypovolemia), and patients may arrive in the OR with both anterior and posterior nasal packs in place (difficult ventilation).

The surgical approach depends on the extent of fractures and associated lacerations. Periorbital incisions can be external, on or below the lower eyelid and over the brow, or internal, along the lower eyelid conjunctiva. Upper facial repair may include a bicoronal approach (Fig. 11.3-4) designed to peel the face off the upper facial skeleton via an ear-to-ear scalp incision. Rainey clips are used to minimize scalp bleeding. Of note, periorbital dissection to explore and repair NOE or orbital floor fractures involves some retraction on the globe. This may cause ↓ HR and ↓ BP via the oculocardiac reflex. The mandible can be approached through external, preauricular or inferior border, or intraoral incisions. A panfacial fracture treatment protocol is illustrated in Figure 11.3-1.

Variant procedure or approaches: Endoscopic approaches are being developed for multiple fracture sites. Resorbable plates and screws, especially for pediatric cases, can be applied through the same surgical approaches.

Usual preop diagnosis: Facial trauma

Figure 11.3-1. Panfacial fracture treatment protocol, based on reconstructing load-bearing structures of the facial skeleton. A: Projection of the midface is created by reconstructing the zygomatic arches, starting from the stable part of the temporal bone. B: The zygomas are fixed to the arches and to the frontal bone to create the final projection of the midface. C: The width of the midface is reconstructed by repositioning the central midface (orbits and nose) to its correct position, in relation to the zygomas and frontal bone. Concomitantly, canthopexy is fixed, and the frontal bone and sinus fractures are treated. (This procedure is independent of the occlusion.) D: The posterior vertical height of the face is reconstructed by positioning and fixing the condylar fractures. E: Intermaxillary fixation is applied, and the mandible is reconstructed. F: Finally, the LeFort I-level fractures are positioned to natural occlusion. (Reproduced with permission from Booth PW, Schendel SA, Hausamen J-E, eds: Maxillofacial Surgery. Churchill Livingstone, Edinburgh: 1999.)

Figure 11.3-2. Schematic of the LeFort fracture lines. A: LeFort III involves separation of cranium from facial bone structure. B: LeFort II is a pyramid-shaped fracture, including the dentition and nasal structures. C: LeFort I is a horizontal fracture involving mobilization of dentition and maxilla. (Reproduced with permission from Booth PW, Schendel SA, Hausamen J-E, eds: Maxillofacial Surgery. Churchill Livingstone, Edinburgh: 1999.)

Figure 11.3-3. A: Anatomic regions of the mandible and B: frequency of fractures in those regions. (Reproduced with permission from Aston SJ, Beasley RW, Thorne CH, eds: Grabb and Smith’s Plastic Surgery. 5th edition. Lippincott-Raven, Philadelphia: 1997.)

Figure 11.3-4. Bicoronal approach. (Reproduced with permission from Booth PW, Schendel SA, Hausamen J-E, eds: Maxillofacial Surgery. Churchill Livingstone, Edinburgh: 1999.)

Figure 11.3-5. Standard anesthesia and surgical setup for a maxillofacial surgical procedure and certain craniofacial surgical procedures. The table may be rotated 90°-180° with anesthesia equipment and personnel at the foot or off to one side. (Reproduced with permission from Bell WH, ed: Modern Practice of Orthognathic Surgery, Vol I. WB Saunders, Philadelphia: 1990.)

▪ SUMMARY OF PROCEDURES

	Mandibular	Maxillary Orbital/Zygomatic	Nasal
Position	Supine	⇚	⇚
Incision	Intraoral; lateral, submandibular	Intraoral, ± subciliary; possibly coronal	Closed reduction; possibly intranasal
Special instrumentation	Air power tools; plate fixation; headlight	⇚ + Periorbital malleable retractors; Rowe disimpaction forceps; acrylic dental split	⇚
Unique considerations	Nasal RAE (sutured to dentition or septum); throat pack; corticosteroids periop to ↓ edema.	Panfacial smash; airway swelling associated with head injury; burns or other system involvement. Consider preop tracheostomy. Close monitoring for and removal of stimulus until oculocardiac reflex recovery.	⇚
Antibiotics, etc.	Cefazolin 1 g iv	⇚ + Methylprednisolone 125 mg iv (adults)	⇚
Surgical time	1-3 h	1-6 h (bicoronal approach adds 1.5 h)	1 h
Closing considerations	NG at end of procedure, maintained for 24 h; IMF postop; NB: Throat pack removal.	⇚	—
EBL	100-800 mL, depending on extent of fractures, need for graft harvest, patient age	⇚	⇚
Postop care	Airway or respiratory status may be compromised (preop and postop swelling/aspiration/associated injuries), requiring maintenance of intubation → ICU.	⇚	⇚
Mortality	Minimal (↑ due to associated injuries and blood loss)	⇚	⇚
Morbidity	Trismus Poor occlusion Drooling Poor cosmetic result Chronic pain/sensation changes Loss of taste	⇚ ⇚ ⇚ ⇚ ⇚ Loss of smell Visual problems/epiphora Sinus problems Breathing difficulty	– – – ⇚ ⇚ ⇚ – ⇚ ⇚
Pain score	4-8	4-8	4-8

▪ PATIENT POPULATION CHARACTERISTICS

Age range	> 4 yr
Male:Female	1:1 (varies by age group)
Incidence	The most common are nasal bones, zygoma and arch, mandible, and orbital floor (on the rise due to airbags in autos).
Etiology	Adults: Motor vehicle accidents (MVAs), mostly young males (43-67%); assaults (13-48.8%); sports-related (3.8%); falls (3.6%); gunshot wounds (3%) Children: Uncommon: only ˜5% of all facial fractures occur in ages < 12 yr; falls (33%); MVA (28%); abuse (3%); dog bites (rare). 69% are periorbital or nasal.
Associated conditions	Airway compromise/closed head trauma (40%); extremity fractures (33%); thoracic injury (29%); open or radiographic brain injury (25%); intraabdominal (12%); globe injuries (11%); oral trauma (11%); pelvic fractures (10%); C-spine fractures (4-10%); T-L spine injuries (4%); shock; multisystem trauma; burns; massive soft-tissue loss. Mandibular fractures during MVAs are associated with a 65% incidence of life-threatening injuries and mortality of up to 8%; up to 1/3 of LeFort fractures will require intubation, most often due to upper respiratory tract blood and secretions.

ANESTHETIC CONSIDERATIONS

PREOPERATIVE

The forces required to produce facial fractures are considerable and frequently result in other associated trauma (e.g., closed head trauma; spine injuries; thoracic injury, including pneumothorax and myocardial contusion; intraabdominal bleeding). Soft-tissue injury to the tongue or larynx can make airway management difficult. When in doubt, a tracheostomy under local anesthesia or awake intubation should be considered. In mandible or maxillary fractures, nasal intubation is usually best because the patient will be placed in intermaxillary fixation (IMF; teeth brought together via wires or rubber bands) at the conclusion of the procedure. In malar or nasal bone fractures, the fixation may be precarious, making it undesirable to use mask ventilation at the termination of the procedure and necessitating awake extubation. Facial nerve monitoring may be required, contraindicating the use of muscle relaxants.

Frequently, the anesthesiologist’s first encounter with these patients is in the ER, where prompt airway management decisions are essential—often before diagnostic imaging studies are complete. These patients should be treated with full-stomach precautions (see p. B-5) and may have already aspirated. Patients may be unable to open their mouths 2° pain or mechanical factors. The cause of limited mouth opening should be determined before induction of anesthesia. Several options exist. Often, the airway can be managed simply by inserting an oropharyngeal airway; failing this, an emergency intubation will be necessary. Blind nasal intubation should be avoided in patients with CSF rhinorrhea or other evidence of nasopharyngeal trauma, where the potential for creating false passages and additional trauma is significant. An awake oral intubation with topical anesthesia is often the safest approach. Emergency oral
intubation may be complicated by an unstable C-spine and limited jaw opening, together with blood and debris in the oropharynx, making visualization difficult if not impossible. Often the only recourse is tracheostomy under local anesthesia. As with any trauma victim, attention is first directed toward maintaining the airway and restoration of fluid volume. The repair of the facial fracture may be carried out incidental to the primary trauma surgery or, more often, is deferred until the patient’s condition is stabilized. The following preop assessment will focus primarily on the patient coming to the OR for semielective repair of a facial fracture.

Airway	Semielective: Usually, facial swelling and intraoral bleeding will have resolved, although mouth opening may be limited 2° pain or mechanical factors. Airway management requires knowledge of the fracture site(s). Patients with a maxillary fracture may benefit from an oral intubation to allow inspection of the nasopharynx before nasal intubation and definitive repair. The possibility of an awake fiberoptic intubation (see p. B-6) should be discussed with the patient. Patients with an isolated orbital, zygomatic, or nasal fracture usually do not present airway management problems. The surgeon should be consulted regarding the preferred intubation route. Trauma: Airway and nasal obstruction following trauma can be extreme, as a result of soft-tissue swelling and accumulated blood and secretions. The extent of facial fractures, particularly in the midface, should be identified as they may preclude nasal intubation. Mandibular fractures may make access to the oropharynx difficult. Unstable dentoalveolar fractures may require preop wiring in the ER. In the case of massive trauma to the face, urgent tracheostomy should be considered. Tests: As indicated from H&P
Respiratory	Trauma: Evaluate for associated trauma and respiratory insufficiency 2° aspiration. 3 that chest tubes are functioning properly. Tests: CXR; others as indicated from H&P
Cardiovascular	Semielective: Typically, several days will have elapsed since the initial trauma, and the patient should be hemodynamically stable. Trauma: Blunt chest trauma may be associated with myocardial contusion, pericardial effusion/ tamponade, and aortic tear/dissection. Tests: ECG; others as indicated from H&P
Neurological	Semielective: Document any neurological deficits and altered mental status. Meningitis may occur in patients with persistent CSF rhinorrhea or pneumocephalus. Trauma: Intracranial injury may be associated with facial fractures. Patients with head trauma may have ↑ ICP; therefore, appropriate methods (e.g., CO₂ ↓, fluid ↓, smooth induction/ intubation) are used to prevent further ↑ ICP. Basilar skull fractures preclude passage of nasotracheal and NG tubes. In the presence of otorrhea or rhinorrhea, positive-pressure mask ventilation is inadvisable due to the potential for causing pneumocephalus. Tests: Review skull and C-spine x-rays.
Musculoskeletal	Semielective: May be associated with other fractures and soft-tissue trauma that may affect patient positioning. Trauma: C-spine injuries are commonly associated with facial injuries. The C-spine should be cleared by clinical and x-ray exam before transport to OR. If C-spine cannot be cleared, intubation should be done with the head in a neutral position (splinted or with axial stabilization), using direct FOL (see p. B-6).
Hematologic	Trauma: Maxillary surgery may be associated with major blood loss. For elective cases, autologous donation should be encouraged. Tests: Hct; others as indicated from H&P
Laboratory	Other tests as indicated from H&P
Premedication	Standard premedication (see p. B-1) is appropriate for nontrauma, neurologically intact patients with normal airways. Trauma: Trauma patients should be considered to have full stomachs, and sedative premedications are best avoided. Aspiration prophylaxis with 0.3 M Na citrate (30 mL po), ± metoclopramide 10 mg iv ± ranitidine 50 mg iv, should be considered.