Special Anatomic Sites




Key Practice Points





  • Although scalp lacerations can appear small and innocuous, they can bleed profusely to the point of hypotension.



  • Hair does not increase the risk of wound infection. Shaving hair increases the risk of wound infection. Hair can be clipped or cleaned to prepare the laceration for closure.



  • Closing scalp lacerations with absorbable sutures, particularly in children, avoids the need for the patient to return for suture or staple removal.



  • The forehead has little redundant tissue. Débride as little as possible to preserve skin for later revision if necessary.



  • Face lacerations do not require dressings. Have the patient apply a small amount of antibiotic ointment daily to the sutured laceration to facilitate easy removal of sutures.



  • Lacerations near the eye can cause several serious complications, such as hyphemas, tear duct injuries, and other problems. Carefully examine the eye and its structures before closure.



  • Never shave an eyebrow. Eyebrow hair does not grow back in some patients, or it grows abnormally.



  • Lacerations to the side of the face can injure the parotid gland or the seventh nerve. Examine these structures before repair.



  • Injuries to the nose can cause a septal hematoma. Use an otoscope to look in the nares to detect hematoma of the septum or exposed cartilage or bone.



  • Lacerations to the ear can involve cartilage. However, it is not necessary to suture cartilage. Closure of skin over the cartilage will bring cartilage into proper position.



  • Alignment of lacerations through the vermilion border of the lip is critical to avoid a noticeable cosmetic defect.



  • If a tooth is knocked out, the prognosis for salvage worsens by the minute. If not replaced within 30 minutes, it is not likely to remain viable.



Although the wound closure principles and suture techniques discussed in Chapter 10 , Chapter 11 can be applied to all lacerations and wounds, several areas of the body have unique anatomic considerations that require special attention. Particular emphasis is placed on facial wounds because of cosmetic concerns. Initial management and wound closure are crucial to the way that scars eventually form and to the final appearance of the injury. Chapter 8 , Table 8-3 , presents a reference guide for sutures and closure materials for each anatomic region of the body. Because of the importance and complexity of the hand, this anatomic feature is covered separately in Chapter 13 .




Scalp


There are five layers of the scalp: skin (epidermis, dermis), dense superficial fascia, galea aponeurotica, loose areolar connective tissue, and periosteum ( Fig. 12-1 ). The skin is densely covered with hair. Ragged lacerations often are closed without regard to cosmetics because of the assumption that hair will hide the scar. Most men experience some balding in their lifetimes, however, a fact that must be taken into consideration during wound closure.




Figure 12-1


Cross-sectional anatomy of the scalp. Note the emissary vein; it can act as a conduit for bacteria to brain tissues if the scalp wound becomes infected.


Underlying the skin is a dense layer of connective tissue that corresponds to the superficial fascia. This layer is richly invested with arteries and veins. Although this profuse vascularity protects against the development of infection, the denseness of the connective tissue tends to hold vessels open when the scalp is lacerated. For this reason, even small lacerations can cause considerable bleeding, leading to hypovolemia, hypotension, and even death. Hemorrhage is worsened if alcohol is present in the blood, which is a finding in 50% of patients with scalp lacerations.


The next layer of skin is the galea aponeurotica ( Fig. 12-2 ). It is a dense, tendon-like structure that covers the skull and inserts into the frontalis muscle of the forehead anteriorly and into the occipitalis muscle posteriorly. Failure to repair large, horizontal lacerations of the aponeurosis can cause the frontalis muscle to contract asymmetrically, which can cause a significant cosmetic deformity of the forehead. Closure of galea lacerations also is important for protection of the loose connective tissue that is vulnerable to infection.




Figure 12-2


Lateral view of galea aponeurotica. Repair of large lacerations of the galea is required to maintain the integrity of facial structures.


Blood and bacteria can spread easily from a laceration of the skin through the injured galea to the loose connective tissue. Within this layer are emissary veins that drain into the skull and intracranial veins. Infection of this space can lead to osteomyelitis or brain abscess. Beneath the loose connective tissue layer is the periosteum of the skull itself. The periosteum can be mistaken for the galea but is not as dense, and it does not readily accept sutures without the risk of tearing.


Preparation for Closure


Visual inspection and digital palpation of large wounds are recommended to identify galeal or bone injuries. The periosteum frequently is injured during trauma. Injuries to this layer often can be seen or palpated through a laceration. Because of its close adherence to the bone, a laceration of the periosteum can be mistaken for a skull fracture. Computerized tomography is recommended to rule out a true fracture, even if the published criteria for computerized tomography in minor head injury are not met.


Hair removal before closure is necessary only if hair interferes with the actual closure and knot tying. Hair is not contaminated with high levels of bacteria and can be cleansed easily with standard wound preparation solutions. In a study of 68 patients with traumatic scalp lacerations, no wound infections were documented in patients whose hair had not been removed before closure. If removal is necessary for mechanical reasons, clipping with scissors or shaving with a recessed blade razor suffices. Shaving at skin level can increase the chance for wound infection. Another method to exposed the laceration before closure is to apply ointment such as Vaseline or antibiotic ointment to the hair around the wound. The hair is then flattened away from the wound before closure.


Because of the scalp’s propensity to bleed profusely, hemorrhage control is necessary before attempting closure. Trying to suture a bleeding scalp wound can be difficult and frustrating. The vessels do not lend themselves to easy clamping or ligation because they are encased in the dense connective tissue. Direct pressure, applied in the manner described in the following text, is an effective way to gain hemostasis. First, gross contaminants, if present, are removed immediately with a brief cleansing or irrigation. Then the wound is covered with sterile, saline-moistened sponges and is compressed with an elastic bandage. This bandage can be left in place for 30 to 60 minutes. After compression, significant bleeding is usually under control.


Injection of lidocaine with epinephrine can also control bleeding. It can anesthetize the wound before formal closure or the application of horizontal mattress ( Fig. 12-3 ) or figure-of-eight sutures, which can also aid in controlling bleeding.




Figure 12-3


Horizontal mattress suture technique for closure of scalp wounds with uneven or macerated edges.


Another method to control scalp hemorrhage is the use of hemostatic agents. In a review of the available agents, oxidized cellulose (Surgicel) and gelatin foams (Gelfoam) are effective for use in skin and scalp wounds. Hemostatic agents should be considered as a last resort. These agents can interfere with suturing of a scalp wound and can take 2 to 6 weeks to be absorbed.


Galeal Lacerations


Because the galea is a key anchoring structure for the frontalis muscle, large frontal galeal lacerations need to be repaired separately with 3-0 or 4-0 absorbable sutures to prevent a serious cosmetic deformity from developing. If the frontalis muscle loses its anchoring point at the muscle-galeal junction along the frontal scalp line, facial expressions dependent on that muscle appear distorted and asymmetric. Closure of large galeal lacerations in other areas of the scalp also is recommended to protect the loose connective tissue layer from infection.


Uncomplicated Lacerations


Uncomplicated, shearing lacerations can be closed with nonabsorbable 5-0 or 4-0 monofilament nylon, staples, or absorbable chromic gut suture. The absorbable chromic gut material often is preferred for children, because suture removal becomes unnecessary. Some practitioners find this strategy equally effective for adults. Absorbable irradiated polyglactin-910 (Vicryl Rapide) also can be used to close scalp wounds, obviating the need for later suture removal. Closure outcomes with this material are similar to outcomes for other methods, in that low rates of dehiscence and infection result. The use of staples is common for scalp wounds. Stapled wounds heal in the same way as wounds treated with standard closure methods. In children, the cosmetic outcome of stapled scalp lacerations is no different from the outcome of lacerations closed with standard sutures. In an analysis of stapling versus suturing, stapling was significantly faster and less costly.


A simple, “low-tech” approach to scalp laceration closure is hair braiding. Because hair removal is not necessary for scalp laceration cleansing and repair, the hair itself can become the closure material. This technique works best for straight and superficial lacerations with enough hair to tie in small knots. The wound is cleansed and irrigated (see Chapter 7 ). About 10 to 20 hairs on each side of the wound are moistened with saline or water and are clumped together to form a “thread.” The two threads are tied together in a simple square knot. Forceps can be used to tighten the knot to prevent slippage. A small amount of cyanoacrylate glue (Dermabond) can be applied to the knot to increase security. Sutures and staples provide more overall wound security, but patients must return for removal of these closures.


Compression Lacerations with Irregular Margins


Lacerations of the scalp are often caused by blunt rather than sharp shearing forces. In these cases, the wound and its edges are irregular and macerated. Simple closure with percutaneous, interrupted sutures can be difficult under these conditions. The scalp does not have excessive tissue redundancy, so débridement has to be kept to a minimum, or the wound cannot be approximated without abnormally high tension. The rich vascularity of the scalp allows for eventual successful healing even if less than optimal tissues are brought together. After judicious wound edge trimming, the horizontal mattress suture technique is recommended to approximate the remaining edges (see Fig. 12-3 ). This technique also is useful for closing an excessively bleeding wound.


Compression injuries can result in complex, stellate lacerations. Judicious débridement is advised. The corner closure (flap) technique, described in Chapter 11 , often approximates all of the corners and flaps in one suture. The remainder of the repair is performed with simple percutaneous or half-buried mattress sutures.


Avulsion or Scalping Lacerations


High-speed forces that are delivered in a tangential manner to the scalp can cause large flaps or complete loss of portions of the scalp. Associated intracranial injury also can occur. These wounds are best managed by a consultant. Preserved portions of complete scalp avulsions, similar to other amputated parts, are wrapped in saline-moistened gauze, are placed in plastic bags, and are cooled over ice. It is possible that they might be reimplanted in the defect by grafting or microvascular anastomosis techniques.


Aftercare


After repair, it is sometimes necessary to place a temporary (24-hour), light-pressure compression wrap with an elastic bandage over the scalp dressing of large lacerations to prevent formation of wound hematoma. The patient can be instructed to remove the bandage after the recommended compression period.


Most scalp lacerations do not require dressing, just a thin layer of an antibacterial ointment. Scalp sutures are left in place for 7 to 9 days for adults and for 5 to 7 days for children. Gentle bathing of the scalp can commence 24 hours after closure. Daily application of ointment after cleansing is recommended.




Forehead


The forehead is a common site of injury in children and adults. The forehead is also of paramount cosmetic importance because of its visibility. Three principles govern the initial repair of a forehead injury, as follows:




  • Skin tension lines that parallel skin creases play a major role in the outcome of any laceration. A laceration that is perpendicular to dynamic skin tension lines tends to heal with a more visible scar than one that is parallel to these lines (see Chapter 3 ).



  • The forehead has little excess tissue to permit extensive revisions and excisions. The temptation to excise ragged wounds has to be assessed carefully or resisted. A small defect can inadvertently become larger by overaggressive repair efforts. It is often best to preserve as much tissue as possible just by “tacking down” ragged tissue tags so that later cosmetic revisions can be made when conditions are more favorable.



  • Whenever possible, avoid the use of dermal (deep) absorbable sutures. Excessive tissue reaction with increased scar size can result from deep sutures.



Preparation for Closure


Anesthesia for small or single lacerations of the forehead can be accomplished by the direct or parallel injection techniques, using an anesthetic with epinephrine to decrease bleeding. Large or multiple lacerations often are managed best by a forehead block (see Chapter 6 ). This block reduces the number of needle-sticks and prevents distortion of the tissues to allow for more accurate wound edge approximation.


When anesthesia is achieved, the wound can be explored for any bony abnormality or foreign body; radiographs are recommended when the suspicion for either is raised. Large pieces of glass can be discovered under small and innocuous-appearing wounds. After gentle scrubbing with a sponge, after irrigation, and after débridement with the tip of a no. 11 blade, most foreign material should have been removed. Any remaining permanent material can be surgically removed. Every effort is made to remove potential tattooing tar or grit at the time of the first repair. When in doubt, consultation with a specialist should be considered.


Uncomplicated Lacerations


Most lacerations can be closed with the simple percutaneous technique using a 6-0 monofilament nonabsorbable suture. Absorbable sutures, such as Vicryl Rapide, can be used for superficial skin closure as well. Deeper lacerations may require placement of a few supporting dermal (deep) 5-0 absorbable sutures. The percutaneous technique in any laceration should be performed by taking small bites (close to the wound edge) with several sutures rather than large bites with few sutures. This technique reduces wound edge tension and allows for more accurate wound edge apposition.


Complex Lacerations


Multiple Small Flaps, Lacerations, and Abrasions (Windshield Injury)


One of the most daunting wounds is a “windshield” injury, characterized by multiple lacerations, abrasions, gouges, and small flaps. The anesthetic technique of choice is the forehead block. Flaps that are smaller than 5 mm in width and length are tacked down with single 6-0 percutaneous nonabsorbable sutures ( Fig. 12-4 ). Larger flaps can be closed using the corner technique. Partial-thickness abrasions and shallow gouges (<5 to 10 mm wide and 1 to 2 mm deep) can be left to heal by secondary intention. Other lacerations are closed as necessary with percutaneous sutures. A petroleum-based antibiotic ointment applied three times a day suffices as a dressing. Because of cosmetic concerns, a consultant might be helpful, especially if the wounds are severe. Consultation also is appropriate if the estimated time of repair would interfere with an emergency physician’s other duties, even if there is little technical challenge.




Figure 12-4


Small abrasions/lacerations, caused by a windshield injury, often can be closed by using simple, single, percutaneous sutures or single corner sutures.


Ragged-Edge Lacerations, Large Flaps, and Tissue Defects


Lacerations with ragged and macerated edges can be trimmed as described in Chapter 9 . If the unevenness or maceration is not extensive, complete excision is an option if the laceration is parallel to the skin tension lines and there is sufficient tissue redundancy. Lacerations perpendicular to skin tension lines have less tissue redundancy and cannot tolerate wide excision. The principle of tissue preservation has to be kept in mind when considering excision. When there is any doubt about tissue availability for excision, the caregiver should try to preserve what is viable or should consult with another experienced surgeon.


Large avulsion flaps and near-scalping injuries are prone to what is called the trapdoor phenomenon, in which congestion and lymphedema lead to unsightly bulging of the flap after repair. The flaps are U-shaped with the base in a superior position on the forehead. These injuries are best managed by an experienced consultant.


Aftercare


Facial lacerations usually do not require dressings. Daily application of an antibacterial ointment after gentle cleansing is recommended for protection and to allow for easier suture removal (by reducing crusting). Cotton swabs moistened with a mild soap and water solution are useful for cleaning in and around facial lacerations. A small amount of antibiotic ointment applied to the laceration after cleaning makes it much easier to remove the sutures. Facial sutures are removed within 3 to 5 days to prevent suture mark formation. Larger lacerations (>2 cm) are supported by wound tape for 1 week after suture removal.




Eyebrow and Eyelid


The eye and periorbital tissues are susceptible to serious injury by relatively minor trauma. Figure 12-5 illustrates various structures that must be checked for damage before repair proceeds. If any of the important anatomic parts discussed here are involved, immediate referral to a consultant is recommended.




Figure 12-5


Important anatomic structures that can be injured during eye trauma. The integrity of these structures must be confirmed before the closure of any laceration (see text).


Lacerations of the medial lower lid can injure the tear duct apparatus (lacrimal canaliculus and nasolacrimal duct) or the medial palpebral ligament at the medial canthus. Copious tears running down the cheek of the patient are a sign of possible tear duct injuries. A laceration of the medial palpebral ligament displaces the lid apparatus laterally, giving the appearance that the patient is “cross-eyed.”


The levator palpebrae muscle is responsible for maintaining the eyelid in its normal position when open. Interruption of the muscle causes traumatic ptosis. Injury to the muscle is suspected when periorbital fat can be seen to extrude from a laceration of the upper lid. Periorbital fat signifies that the orbital septum has been violated. The levator muscle originates from the septum; any septum injury risks this muscle.


Close inspection of the eye itself is necessary to rule out a hyphema, corneal abrasions, blow-out fracture, and foreign bodies. A complete examination of the eye includes extraocular muscle function, pupil reaction, and corneal staining. Of these injuries, hyphema is the most serious. It is caused by a direct blow to the eye and is recognized by a blood layer in the anterior chamber of the eye in patients in the upright position. In patients who are supine, blood distributes evenly in the anterior chamber over the iris and gives the iris a color different from the opposite iris. The patient also complains of decreased vision in the affected eye. Having the patient sit up reveals the hyphema as the blood settles with gravity.


Preparation for Closure


It is best to deliver an anesthetic to the eyelid by direct wound infiltration, using a small 27G or 30G needle. Epinephrine-containing anesthetics are not necessary. For the eyebrow, the same technique is used, but epinephrine in the anesthetic can be useful to control minor bleeding. Special care is taken to minimize spillage of cleansing agents into the eye to prevent unnecessary corneal irritation. Povidone-iodine solution (not a detergent-containing solution) diluted 1:10 with saline and nonionic surfactants (Shur-Clens) are the cleansing agents of choice. Inadvertent spilling of these preparations can be prevented by holding a folded 4 × 4 sponge over the closed eyelid margin to absorb free solution. The caregiver should never shave the hair from the lid margin or brow because of the unpredictability of hair regrowth in these locations.


Closure of Extramarginal Lid Lacerations


Extramarginal lacerations are usually horizontal and occur most commonly in the upper lid. If extramarginal lacerations are simple and superficial, they can be repaired with a single layer of 6-0 nonabsorbable suture material ( Fig. 12-6 ). No dressing is applied. These lacerations heal well enough that scars become virtually unnoticeable with time.


May 12, 2019 | Posted by in ANESTHESIA | Comments Off on Special Anatomic Sites

Full access? Get Clinical Tree

Get Clinical Tree app for offline access