Penetrating

Wounds of the Head and Neck

Robert A. Jahrsdoerfer, MD; Michael E. Johns, MD; Robert W. Cantrell, MD

\s=b\ Wounding capability of bullets is primarily related to velocity. Bullet mass and shape, and specific gravity of body tissues being struck by the missile, are lesser factors. Seventy cases of penetrating wounds of the head and neck were treated during a six-year period. Vascular injuries were more common with neck wounds, while face and head injuries (extracranial) were similar to maxillofacial trauma. It is recognized that hemorrhage

at the base of the skull is difficult to treat, and contemporary training in temporal bone and base of skull surgery is mandatory for the critical management of these wounds.

(Arch Otolaryngol 105:721-725, 1979) the 0.44 caliber terrorized the for a year and 12 of New York days before his capture on Aug 10, 1977. During his reign of terror, six people were shot to death and seven were wounded. His weapon was a fiveshot Charter Arms Bulldog pistol, which he gripped with two hands and from a crouched position methodically fired four times, close range, at his victims. A year earlier, there appeared in one of the nation's leading newspaof

Sonkiller,Sam",City alleged population

Accepted for publication Nov 21, 1978. From the Department of Otolaryngology and Maxillofacial Surgery, University of Virginia Medical Center, Charlottesville. Reprint requests to Department of Otolaryngology and Maxillofacial Surgery, Box 430, University of Virginia Medical Center, Charlottesville, VA 22908 (Dr Jahrsdoerfer).

pers an article on a proposed change in the type of sidearm ammunition used

by

the

Metropolitan Police Depart¬

Law enforcement officials wanted to change from rounded lead bullets to hollow-point bullets. Those arguing for the latter spoke of "stop¬ ping power" and the "need to neutral¬ ize" the assailant. It was stated that hollow-point bullets would have less tendency to pass through an assail¬ ant's body and therefore less chance of wounding innocent bystanders. Hollow-point bullets are not new to the police. They are used routinely by the Federal Bureau of Investigation as well as other law enforcement agencies. Hollow-point bullets expand on impact and characteristically cre¬ ate a larger wound than a regular round-nosed lead bullet. Hollow-point bullets should not be confused with dumdum bullets, which are softpointed bullets fired from a rifle at high velocity. Dumdum bullets also expand on impact and create an ugly wound. Both newspaper stories served to bring into focus the real and poten¬ tial lethality of present-day handguns and ammunition. ment.1

WOUND CAPABILITY OF MISSILES

Bullet velocity is considered the major factor in the degree of destruc¬ tion a missile causes to the body. The mass of the bullet plays a somewhat lesser role. High-velocity bullets are

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those whose

speed is more than 608 (2,000 ft/s), while low-velocity bullets travel at speeds of 304 m/s (1,000 ft/s) or less. Bullet velocities of m/s

some common

weapons

are as

follows:

.38-caliber, 244 m/s (800 ft/s); .45caliber Colt, 262 m/s (860 ft/s); .22caliber, 335 m/s (1,100 ft/s); shotgun, 366 m/s (1,200 ft/s); .357 magnum side arm, 457 m/s (1,500 ft/s); 30-30 Winchester, 670 m/s (2,200 ft/s); 5.56mm M-16, 975 m/s (3,200 ft/s). The kinetic energy of the bullet imparted

Fig 1.—Types of permanent cavities by high-velocity missiles.

pro¬

duced

Fig 2—Temporary cavity produced by high-velocity missile.

Fig 3.—Top, Anteroposterior radiograph of neck showing frag¬ mented missile in right side of neck. Smaller fragments are seen on

left. Marker (M) indicates point of in soft tissues of neck.

emphysema

entry. Note

subcutaneous

Fig 4.—Bottom left, Neck exploration. Note entrance wound (E), transected ends of vagus nerve (V), common carotid artery (C), and missile path (P) into larynx. Internal jugular vein had been obliterated by missile.

Fig 5.—Bottom right, Anteroposterior film after swallow of radiographic contrast material in patient who sustained gunshot wound to cervical esophagus. Note dye (arrows) spilling into right side of thoracic cavity. Bullet had pierced posterior esophageal wall to lodge against vertebral column at level of C-6.

to the body on impact is proportional to the mass but increases by the square of the velocity. Therefore,

doubling the mass doubles the kinetic energy, while doubling the velocity quadruples the energy. The design of high-velocity bullets is of two main types: expanding (sporting) and fulljacketed (military).1-' Most hunting rifles in use today use a soft-nosed

bullet, which expands on impact. The type of permanent cavity produced is

cone-shaped, with the exit wound being much larger than the entrance wound. Full-jacketed or military bul¬ lets are high-velocity missiles that create a permanent cavity, cylindrical in shape, that roughly conforms to the size of the missile (Fig 1). High-velocity missiles also create a

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temporary cavity

on

passage

through

the body (Fig 2). Kinetic energy transmitted to the body tissues on impact, and as the missile tears through the body, is imparted to the surrounding tissue structures to cre¬ ate

a

pulsating, momentary cavity

that may do considerable damage to body structures not directly in the bullet's path. Arteries and veins may

be injured without actually being struck by the missiles, and vital thoracic structures may be damaged by a wound tangential to the chest. The specific gravity of body tissues in the path of the high-velocity missile determines, in large part, the degree of destruction.1' Compact, capsulated organs such as the spleen and kidneys are particularly vulnerable. Bone, be¬ ing of a relatively high specific gravi¬ ty, undergoes marked shattering and destruction on impact. The huge, gaping wound in the skull of Presi¬ dent Kennedy is an example of this. Lung tissue has a low specific gravity and may withstand a direct hit with minimal damage. Tissue with an increased elastic tissue content also better withstands penetrating trau¬ ma. This is not to say that low-velocity bullets from conventional side arms may not kill. Even blank ammunition can cause death.' For clinical purposes in the diagno¬ sis of penetrating wounds, the neck can be divided into three zones/' Zone 1 includes the base of the neck and is situated below the clavicles. This area may be frequently involved in stab wounds where the downward thrust of the knife carries the point of the blade into the chest. Large arteries, ie,

subclavian, innominate, common ca¬ rotid, and vertebral, may be lacerated

and require thoracotomy with or with¬ out neck exploration. Zone 2 injuries, angle of mandible to sternal notch, frequently involve the carotid artery and internal jugular vein. Hemor¬ rhage in this area is often amenable to prompt exploration. Zone 3 injuries, those above the angle of the mandible, may involve the internal carotid artery or internal jugular vein at the base of the skull. It is generally agreed that vascular injury at the base of the skull is difficult to control."" However, the training of the contemporary otolaryngologist in temporal bone and base of skull surgery makes him particular¬ ly qualified to control zone 3 hemor¬ rhage. If other measures have failed to stop base of skull bleeding, the internal jugular vein can then be controlled by a mastoidectomy and compression of the sigmoid portion of the lateral sinus. The internal carotid

artery can be exposed and compressed

within the carotid canal as it courses through the temporal bone. Access to the internal carotid artery within its bony canal may be achieved in either of two ways. First, there is a postau¬ ricular approach to the middle ear with tympanotomy and elevation of the tympanic membrane off the malleus handle. The internal carotid artery may then be exposed by unroofing the medial wall of the Eustachian tube. Second, there is a preauricular approach with anterior retraction of the parotid gland, man¬ dibular condylectomy, and removal of the tympanic plate. This latter

require partial resec¬ tion of the parotid gland and transec-

approach

may

tion of the facial

nerve

with subse¬

quent end-to-end anastomosis. Both of these approaches take time and should be done in a controlled manner after major base of skull bleeding has been temporarily contained by pack¬ ing. Once the artery has been isolated in the carotid canal, it can be encircled with a rubber loop or packed off with oxidized cellulose. Both measures will allow control of backbleeding and permit an assessment of the repairability of the blood vessel. If primary repair is not possible, the internal carotid artery can be ligated or permanently packed off with oxidized cellulose. The sigmoid sinus is very difficult to ligate and is best handled by packing with oxidized cellulose or microfibrillar collagen. The question of whether or not to routinely explore all penetrating neck wounds has been well covered by May et al." Those who advocate selective exploration predicate their decision on statistics from busy metropolitan hos¬ pitals where sheer weight of numbers may so overburden the emergency room staff that patients with pene¬ trating neck wounds may be triaged to a holding pattern and observed for long periods of time. If the patient's condition remained stable for eight to 12 hours, he was usually admitted for observation and subsequently dis¬

charged

There

in

a

are

day or two.

indicators that should

encourage exploration of a neck wound: persistent hemorrhage, large or expanding hematoma, absent or

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decreased

pulses, progressive

deficit, difficulty breathing from

CNS tra¬

chéal compression, presence of air in subcutaneous tissues, abrupt change in voice, and evidence of cervical

esophageal perforation. Persistent hemorrhage or a large expanding hematoma is a sign of major vascular injury. Palpation of distal pulses and auscultation of the neck are important in diagnosing less obvious, but equally serious, arterial injuries. Absent or decreased pulses may indicate a partially severed artery, while a progressive CNS defi¬ ciency may be the result of an intralu-

minal hematoma. Submucosal hemor¬ rhage in the larynx may cause an abrupt voice change and forebode an airway problem. However, even in the absence of these indicators, explora¬ tion should be undertaken if the examining physician is suspicious that a vital structure has been injured. During the initial emergency room examination it should be determined if the penetrating wound has pierced the platysma. If so, then further prob¬ ing is unjustified. Deep probing beyond the platysma may dislodge a clot in a major vessel and result in a catastrophic hemorrhage. Blind clamping is to be avoided. Most bleeding from zone 2 penetrat¬ ing wounds of the neck can be initially controlled by simple pressure. Howev¬ er, there are two exceptions. One, a wound wherein the missile has tran¬ sected a major vessel before penetrat¬ ing into the upper airway or upper digestive tract (Fig 3 and 4). Profuse bleeding may occur medially along the missile tract to enter the larynx or hypopharynx. Emergency endotra¬ cheal intubation may be required with immediate packing of the laryngopharynx for tamponade. It is unwise to inspect the larynx and hypophar¬ ynx by direct laryngoscopy unless the airway has been first secured by an endotracheal tube or a tracheotomy. Pressure of the laryngoscope blade on the anterior larynx may dislodge a blood clot in the missile tract and result in massive hemorrhage. Either tube must have an inflatable cuff to seal the airway and prevent aspiration of blood. The possibility of a cervical spine injury must not be overlooked

Lateral radiograph showing 3-cm blade embedded in face. Handle had broken off when "punched" in face.

Fig 6.—Top left,

(5-in) knife patient was

Fig 7.—Bottom left, Entrance wound on left side of face in victim who was shot at close range. Bullet passed through soft tissue of face, fractured condyle of mandible, crossed temporal bone at level of tympanic membrane to lodge in mastoid. Fig 8.—Top right, Jacketed 0.25-caliber bullet lodged in left mastoid. Missile had obliterated eardrum, dislocated incus, and fractured stapes. when considering emergency intuba¬ tion. The second exception to simple pressure control of hemorrhage from the neck involves laceration or transection of the vertebral artery. As the vertebral artery ascends in the neck, it runs through intervertebral foramina from C-6 to C-1 before entering the foramen magnum. In this pathway, it is not amenable to digital pressure, and control of hemorrhage by simple compression is difficult. Radiographie evidence of a fracture to the trans¬ verse processes of C-2 to C-6, accom-

panied by heavy bleeding, should be viewed with suspicion of vertebral artery injury. An expanding mass in the posterior triangle and a systolic

bruit on auscultation would indicate a vertebral artery false aneurysm. Symptoms of basilar-vertebral artery ischemia should be carefully watched for. A vertebral arteriogram is essen¬ tial to the diagnosis. Control of hemorrhage from the vertebral artery requires neck explo¬ ration, excision of one or more trans¬ verse processes, and proximal and distal ligation of the vessel. We have

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found

no

reports in the literature of

primary repair to a lacerated or tran¬

sected vertebral artery. Penetrating wounds to the cervical esophagus should be explored. The esophagus should be closed primarily and drains placed in the paraesophageal space. Penetrating wounds to the pirif orm sinuses or cervical esophagus have the potential for serious compli¬ cation. During the act of swallowing, a positive pressure is generated in the inferior hypopharynx and cervical esophagus. Saliva may be forced through the wound tract into the

paraesophageal space. Failure to ade¬ quately drain this space will usually

result in abscess formation. The abscess may dissect the paraesophag¬ eal space inferiorly to its termination at the main stem carina and break through into the mediastinum and chest cavity (Fig 5). Once this occurs, the prognosis is grave. Penetrating wounds of the oral cavity, pharynx, and nasopharynx have less likelihood of salivary contamination than diges¬ tive tract injuries lower in the neck. PENETRATING WOUNDS OF THE FACE AND HEAD

(EXTRACRANIAL) Bullet wounds to the head and facial skeleton are largely dependent on the velocity of the missile. Since bone is of high specific gravity, it is more vul¬ nerable to shattering and splintering than other body tissue of lower specif¬ ic gravity. A .38-caliber round-nosed bullet traveling at 244 m/s (800 ft/s) may do minimal soft-tissue and bony destruction to the face despite being fired at close range. However, a highvelocity jacketed bullet may literally explode the facial skeleton into multi¬ ple bony shards. Early management of penetrating face and head wounds embodies basic principles of emergency care regard¬ ing airway and control of bleeding. There is no rationale for probing extracranial penetrating wounds and to do so may provoke massive hemor¬ rhage. Radiographs are invaluable and will usually show the location of the missile as well as its path as determined from residual metal and bone fragments. Radiographs of the skull and facial skeleton may reveal a penetrating foreign body where none was expected (Fig 6) or may fail to show a metallic foreign body despite an entrance wound and lack of exit wound. The latter example may arise

in three ways. First, the tract may be from a stab wound; second, a bullet upon entering the neck may strike the vertebral column and ricochet anteri¬ orly to perforate into the nasopharynx or pharynx and then be swallowed; third, a bullet, on piercing the soft tissue of the head and neck, may enter a large blood vessel and be embolized to a distant location. Bullet embolization is rare, but has been reported on several occasions. In 7,500 vascular trauma cases in Vietnam, 22 were recorded as missile emboli."1 Ledgerwood" has recently reviewed the subject of wandering bullets. The treatment of extracranial pene¬ trating wounds requires some experi¬ ence in base of skull surgery. Patients with missile wounds to the temporal bone should have preoperative arteriograms obtained to assess possible injury to the internal carotid artery, sigmoid sinus, and jugular bulb. The temporal bone usually fractures from the impact velocity of the missile. This may occur directly or from transmit¬ ted energy from a bullet striking the condyle of the mandible. Fracture lines may involve the middle cranial fossa, facial nerve, and the cochlea and vestibular labyrinth. Exploration should be selective, and CSF otorrhea should be managed expectantly until the leak has stopped. Fragments of skin from the tympanic membrane and external ear canal may be driven deep into the mastoid or petrous portions of the temporal bone. Debridement may be necessary to avoid cholesteatoma formation (Fig 7 and

8).

Seventy cases of penetrating head and neck wounds were evaluated and treated during the past six years. There were 60 male and ten female patients. Sixty-seven patients

adults and three mean

were

children. The age was 31 years. Of the 33 neck were

wounds, were

25

gunshot wounds, six knives, one was from a

were

from

glass shard, and one was from a ball¬ point pen. Of the 37 head wounds, 35 were gunshot wounds and two were

knife wounds. The anatomic distribu¬ tion of the injuries, either alone or in combination is as follows: common carotid artery, 3; internal carotid artery, 1; vertebral artery, 1; superior thyroid artery, 2; internal jugular vein, 4; other veins, 1; trachea, 3; esophagus, 2; spinal cord, 4; brachial plexus, 1; cranial nerves, 2; and sali¬ vary glands, 4. There were three deaths among the 33 patients with penetrating neck wounds: vertebral artery laceration; an esophageal perforation with mediastinitis and empyema; and a spinal cord transection at C-3 with respirato¬ ry arrest. The remaining three spinal cord injuries were at levels C5-6 and resulted in quadriplegia. Stab wounds were more common in the neck (6/33) as compared with the face and head (2/37). There were no deaths in the group with face and head injuries. Patients with penetrating wounds of the face and head usually mani¬ fested wounds similar to those with maxillofacial trauma. The facial skele¬ ton was often fractured, and of the facial bones the mandible was most often involved. In two cases, the force of the bullet striking and fracturing the condyle of the mandible resulted in a corresponding fracture of the temporal bone. Penetrating wounds from shotgun pellets accounted for four cases in the face and head group and only one case in the neck group. In two cases, pellets, caused carotid artery injuries. One important differ¬ ence between blunt maxillofacial trau¬ ma and penetrating wounds of the head and neck is that vascular struc¬ tures are more likely to be injured in the latter.

References 1. Lynton SJ, Lewis AE: More powerful bullets studied by D.C. police. The Washington Post p 1, Nov 5, 1976. 2. DeMuth WE: Bullet velocity and design as determinants of wounding capability: An experimental study. J Trauma 6:222-232, 1966. 3. DeMuth WE: Bullet velocity makes the difference. J Trauma 9:642-643, 1969. 4. Cloos JD: Wounding effects of blank ammu-

nition. FBI Law Enforce Bull 47:21-25, 1978. 5. Saletta JD, Lowe RJ, Lim LT, et al: Penetrating trauma of the neck. Trauma 16:579-587, 1976. 6. Monson DO, Saletta JD, Freeark RJ: Carotid vertebral trauma. J Trauma 9:987-999, 1969. 7. Penn I: Penetrating injuries of the neck. Surg Clin North Am 53:1469-1478, 1973. 8. Enker WE, Simonowitz D: Experience in the J

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operative management of penetrating injuries of the neck. Surg Clin North Am 53:87-95, 1973. 9. May M, Chadaratana P, West JW, et al: Penetrating neck wounds: Selective exploration. Laryngoscope 85:57-75, 1975. 10. Rich NM, Collins GJ, Andersen CA, et al: Missile emboli. Trauma 18:236-239, 1978. 11. Ledgerwood AM: The wandering bullet. Surg Clin North Am 57:97-109, 1977. J

Penetrating wounds of the head and neck.

Penetrating Wounds of the Head and Neck Robert A. Jahrsdoerfer, MD; Michael E. Johns, MD; Robert W. Cantrell, MD \s=b\ Wounding capability of bulle...
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