Trauma

The Times They Are A Changin': the "No Zone" Approach to Management of Penetrating Neck Trauma

Clinical Case: You're working a busy evening shift when a middle aged woman is brought in by EMS from the scene of a car accident.  She has a deep laceration to her anterior neck near the level of the cricoid cartilage from a glass shard.  She is neurologically intact, talking with a normal voice and is in no respiratory distress.  However, there is a continuous and brisk oozing of blood from the wound.

Clinical Question: What imaging is indicated in hemodynamically stable, neurologically intact patients with penetrating neck injuries?  What should the typical disposition be?

Literature Review:
Any neck wound that extends deep to the platysma is considered a penetrating neck wound, and it is estimated that they represent 5-10% of all trauma patients who arrive to the emergency department. Two common ways of anatomically dividing the neck include using the sternocleidomastoid to divide the neck into anterior and posterior triangles, or dividing the neck into three zones [1]:


    In the event of penetrating injury to the neck, airway compromise should be immediately assessed, with early intubation for airway protection if there is any concern for expanding neck hematoma or concerns for airway injury.  An attempt can be made to orotracheally intubate (bougies have been suggested as excellent initial adjuncts [2]), but plans should be made to move to early cricothyroidotomy if the airway is unable to be secured from above. After securing the airway and establishing hemodynamic stability, the neck wound should be carefully inspected.  Injuries that breach the platysma may have caused significant underlying injury, and it is best to avoid probing these wounds at the bedside, as this could disrupt hemostasis.  Aside from risk of vascular disruption, patients with penetrating neck injuries warrant consideration of tracheal and esophageal compromise.  Signs of tracheal injury include air bubbling at the wound, hemoptysis, subcutaneous emphysema, and stridor.  Esophageal injuries can be initially be asymptomatic, and a missed injury can lead to neck space infection and mediastinitis [3].   Emergent surgical consultation is warranted, as patients with hemodynamic instability and/or "hard signs" of vascular or aerodigestive tract injury should go for emergent neck exploration [3].

    Classically, management of hemodynamically stable patients with penetrating neck injuries was based on an anatomic "zone-based" approach mentioned above, with zone II injuries often going directly to surgical exploration and zone I and III injuries undergoing angiography, bronchoscopy, and esophagoscopy.  This approach was developed in the 1970’s, but it had several problems [4].  First, there may be poor correlation between the location of the neck wound and internal organ involvement, as there may be traversing of zones internally. Secondarily, the adoption of a mandatory-exploration policy lead to a high negative exploration rate (53% - 56%)[4,5].

    With the rapid improvement and dissemination of the use of  CT over the past few decades, a “No Zone” management approach based on careful physical exam with CT angiography has been shown in surgical literature to decrease resource utilization and unnecessary surgical exploration, making the rigid zone approach less relevant [3].   Several studies have examined the sensitivity and specificity of CT angiography in stable patients with penetrating neck injury.  A study by Inaba et. al. prospectively evaluated an algorithm in which patients with "soft signs" of injury (venous oozing, non-expanding hematoma, minor hemoptysis, dysphonia, dysphagia, or small amount of subcutaneous emphysema) underwent an initial evaluation with CT-angiography and asymptomatic patients were observed [6].  Over a 31-month period, 453 patients with penetrating neck trauma were prospectively evaluated in their study.  186 of these patients had "soft signs" of clinical injury, and underwent CT angiography as their initial method of evaluation.  38.2% of these patients had an injury to zone II of the neck.  Using an aggregate gold standard of the final diagnosis at discharge which included operative exploration, catheter-based angiography, bronchoscopy, esophagogram and esophagoscopy results and clinical follow-up (duration not specified),  the sensitivity and specificity of CT Angiography for vascular or aerodigestive injury was 100% and 97.5 % respectively.  There were two patients who had false-positive findings of vascular injury (irregularities in the ICA) that were not present on follow-up with surgical exploration and/or angiography, and three patients had air tracking suspicious for aerodigestive tract injury that was not confirmed on follow-up imaging and endoscopic studies. 

    As mentioned above, the "No Zone" approach combining clinical exam with imaging evaluation has the potential to decrease unnecessary neck exploration. A study by Osborn et. al. examined the rate of negative neck explorations in patients who were taken to the OR who did not have hard signs of injury.  They compared the rate of negative neck explorations amongst those patients who had a CT-A as part of their initial evaluation and those who did not, and found that CT angiography significantly reduced the negative neck exploration rate [7]:

    Source: Osborn et al. (2008)
     In their review of penetrating neck trauma management, Shiroff at al. shared the algorithm below, comparing the traditional vs. "no zone" approach:

    Image Source:  Reference 3



    Take Home Points: Patients with penetrating neck trauma who are hemodynamically unstable or  display hard signs of vascular or aerodigestive should receive immediate surgical consultation with consideration for operative or invasive management.  As the traditional, anatomic approach to management of penetrating neck trauma is associated with a high rate of negative neck exploration, patients with soft signs of injury should be initially evaluated with CT angiography which has a high sensitivity for clinically-significant injury.

    Submitted by Philip Chan, PGY-3
    Edited by Maia Dorsett (@maiadorsett), PGY-4
    Faculty reviewed by jason wagner (@TheTechDoc)

    References
    [1] Tintinalli’s Emergency Medicine, 7e.  Ch 257. 
    [2] Daniel, Y., de Regloix, S., & Kaiser, E. (2014). Use of a Gum Elastic Bougie in a Penetrating Neck Trauma. Prehospital and disaster medicine, 29(02), 212-213.
    [3] Shiroff, A. M., Gale, S. C., Martin, N. D., Marchalik, D., Petrov, D., Ahmed, H. M., ... & Gracias, V. H. (2013). Penetrating neck trauma: a review of management strategies and discussion of the ‘No Zone’approach. The American Surgeon, 79(1), 23-29.
    [4] Prichayudh, S., Choadrachata-anun, J., Sriussadaporn, S., Pak-art, R., Sriussadaporn, S., Kritayakirana, K., & Samorn, P. (2015). Selective management of penetrating neck injuries using “no zone” approach. Injury.
    [5] Varghese, A. (2013). Penetrating neck injury: a case report and review of management. Indian Journal of Surgery, 75(1), 43-46.
    [6] Inaba, K., Branco, B. C., Menaker, J., Scalea, T. M., Crane, S., DuBose, J. J., ... & Demetriades, D. (2012). Evaluation of multidetector computed tomography for penetrating neck injury: a prospective multicenter study. Journal of Trauma and Acute Care Surgery, 72(3), 576-584.
    [7] Osborn, T. M., Bell, R. B., Qaisi, W., & Long, W. B. (2008). Computed tomographic angiography as an aid to clinical decision making in the selective management of penetrating injuries to the neck: a reduction in the need for operative exploration. Journal of Trauma and Acute Care Surgery, 64(6), 1466-1471.

    On Broken Teeth: Emergency Management of Dental Fractures

    Clinical Scenario: One evening in the ED, a teenage boy is brought in by his mother for dental trauma after an altercation at school.  The boy reports that he was pushed to the ground in the scuffle, hitting face first into the concrete. On exam, pinkish-red material was visible at base of what remains of his frontal incisorsIt's been awhile since you took care of dental trauma and you decide to read more about it. 

    Clinical Question: What are the different layers of teeth and how do they impact severity of dental injury? What are the risk factors for dental injury? How are dental fractures graded and what steps should the ED physician take to protect remaining tooth fragments? 

    Source: wikipedia.org
    Review: Traumatic dental injuries (TDI) are a common occurrence in both children and adults. Approximately 1 in 3 adults sustain dental trauma during their lifetime, the majority which occur in childhood. A wide variety of risk factors have been described in the literature. These include patient specific factors like ADHD, epilepsy, cerebral palsy, propensity for risk-taking behavior, and anatomic factors like over-jet (the horizontal distance between posterior surface of the maxillary incisors and the anterior surface of the mandibular incisors) and inadequate lip coverage. In a review of rates of TDI in epileptic patients, over half had suffered TDI, many with multiple injuries. Environmental factors include poor socioeconomic status, living in an overcrowded environment and poor road safety [1]. Etiologies of TDI are broad with the most common mechanism of injury being falls. Adolescents and adults are more likely to sustain TDI through organized sporting activities, traffic accidents and violent means including fighting and assault.  In children, dental fractures can be a presentation of non-accidental trauma, and therefore a complete a full physical exam, including skin exam, should be performed

    With regard to anatomy, primary dentition consists of 20 teeth – 8 incisors, 4 canines and 8 molars, classically lettered A – T. The permanent dentition includes 28 to 32 teeth – 8 incisors, 4 canines, 8 premolars and 8 - 12 molars. The 32 permanent teeth are numbered from right to left on top and left to right on the bottom [2].

    With regard to anatomy of the individual teeth, from the inside out a tooth is composed of pulp, dentin and enamel [2]. The visible portion of the tooth is referred to as the crown and consists all three layers. As the tooth extends underneath the gum line, the enamel portion thins and the dentin and pulp extend in to the alveolar bone covered by a thin layer of cementum. The apex of the tooth is the entry point of the neurovascular bundle supplying each tooth. Finally,  the periodontal ligament is a collagenous strructure that extends from the alveolar bone to the cementum surrounding the root of the tooth.


    Image source: Tintinalli, JE et al: Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th Ed via Accessmedicine.com
    The primary traumatic dental injury classifications are concussion, subluxation, extrusion, luxation, intrusion, avulsion and fracture [3].  Examination of a TDI should include visual inspection, percussion testing, manual evaluation of tooth mobility and consideration for radiographic imaging to evaluate for associated alveolar bone injury and widening of the periodontal ligament space. Sensitivity testing (cold testing) is often less useful at the time of injury due to transient lack of pulpal response.   

    Dental fractures aka "broken teeth" require different management based on the extent of the injuryThe Ellis classification, which subdivides dental fractures into three classes of injury is useful for ED providers because it determines emergent care of the dental fracture [4]: 
                  -    Ellis I fractures involve only the enamel.  They typically require no emergency treatment. If sharp edges are present, those can be smoothed for patient comfort. Dentist follow up can be at the patient’s convenience.
                  -    Ellis II fractures involve the dentin but not the pulp  and  can be identified on exam by the creamy yellow color of dentin compared to the whiter, harder enamel.  These fractures require more urgent care.  Because dentin is a microtubular structure, Ellis II fractures threaten the integrity of the pulp and can lead to contamination of the pulp by oral flora . After recognizing an Ellis II fracture, the ED provider should anesthetize, clean and dry the tooth (Peridex can be used to sterilize the tooth) and seal the exposed dentin, which can be done with dental cement . Urgent dental follow up in the next 24 hours is recommended. Patients will require frequent visits and radiographs.
                  -   Ellis III fractures are full thickness and expose the pulp.  They can be identified by visualization of the pink-red pulp as well as bleeding from the pulp on cleaning of the tooth. Like Ellis II injuries, the pulp is at risk with these injuries but at a greater extent given the direct exposure of pulp to the oral environment. Ellis class III injuries require a two step sealing procedure. After anesthetizing, cleaning and drying the tooth, bleeding should be controlled with careful direct pressure. The first sealant layer is a calcium hydroxide base. On top of this base, the same dental cement coverage is applied. Like Ellis II injuries, Ellis III injuries require urgent dental follow up preferably within 24 hours.   

    For children with injuries to primary teeth, pulp exposure is more often encountered given the relatively larger size of the pulp. The same approach to different fracture types are recommended for children. Children will often require a pulpotomy to better protect the pulp from infection, but this requires more specialized tools and can be performed by the dentist in rapid follow up.

    Because dental fractures can have associated injuries, it is important to examine for associated intraoral lacerations, tooth subluxation or avulsion. Subluxations and avulsions may require repositioning of the tooth and splinting to adjacent teeth with zinc oxide based dressings like Coe-Pak  [little trick of the trade: since the applications of dental splints requires teeth to be dry, cut off the end of oxygen tubing and attach to the air or oxygen on the wall to blow air onto the teeth and dry them prior to application of an adhesive dental splint]. 

    With all of these injuries, patients should be discharged with oral analgesics, a soft diet and urgent dental follow-up. Generally, topical anesthetics should be avoided. Routine use of systemic antibiotics has not demonstrated benefit, but patient specific factors, associated injuries and co-morbidities should be considered [5].    
      
    Take-Home Points:  Dental fracture management depends on the Ellis classification. Anything more than an Ellis I fracture requires some degree of a protective coating applied in the ED and referral to urgent dental follow up.  Always examine patients thoroughly for other associated injuries and watch for NAT. 

    Submitted by Sara Manning (@EM_SaraM), PGY-4
    Faculty Reviewed by Rob Poirier

    Everyday EBM Editor: Maia Dorsett (@maiadorsett)  

    In case you were thinking that "Broken Teeth" would be a good name for a band, it's already taken.  Thank you google.  

    References:
    1. Glendor, U, “Aetiology and risk factors related to traumatic dental injuries a review of the literature.” 2009. Dental Traumatology. Vol 25: 19 – 31. 
    2. Tintinalli, JE et al, : Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th Ed via Accessmedicine.com 
    3. Dentaltraumaguide.org
    4.DiAngelis et al, “International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 1. Fractures and luxations of permanent teeth.” 2012 Dental Traumatology. Vol 28: 2 – 12. 
    5. ANDREASEN, J. O., STORGÅRD JENSEN, S. I. M. O. N., & SAE‐LIM, V. A. R. A. W. A. N. (2006). The role of antibiotics in preventing healing complications after traumatic dental injuries: a literature review. Endodontic Topics, 14(1), 80-92.

    Theme Image Source: http://www.windsorstar.com

    Needle that belly!

    An infant female with no significant history presents to your trauma bay after reported accidental blunt trauma to the abdomen, the patient arrives from a referral hospital where plain films demonstrated free air. On arrival the patient show signs of hemodynamic instability and an elevated lactate. The patient was decompressed with "needle peritoneumostomy" prior to going to the OR for exploration. 

    Clinical Question:

    Can “tension pneumoperitoneum” cause hemodynamic instability?

    Literature Review:

    The presence of "free air" in the peritoneum is often diagnostically significant; however, the gas itself is rarely of clinical importance. An exception to this rule is in the case of a tension pneumoperitoneum. Tension pneumoperitoneum (TPP), also known as hyperacute abdominal
    Example of pneumoperitoneum & football sign
    compartment syndrome [1], or abdominal tamponade [2], is a rare, but potentially deadly event. Similar to tension pneumothorax, the underlying mechanism is a tissue flap that acts as a one-way valve for air release, resulting in a progressive increase in intra-abdominal pressure. The increasing peritoneal pressures may rapidly lead to respiratory compromise due to diaphragmatic elevation and a drop in cardiac output resulting from decreased venous return or aortic outflow due to occlusion. [3] This can progress to cardiovascular collapse and respiratory failure and eventually death. [2]

    In one of the earliest reported cases in 1913, tension pneumoperitoneum was theorized to be a consequence of gas forming bacteria in the abdominal cavity. [4] Now it is known that tension pneumoperitoneum is usually a consequence of hollow viscus perforation, post-operative complications, positive pressure ventilation or other insulflation-dependent procedures (eg, colonoscopy, endoscopy, cystoscopy or air enema). There has even been reported cases from CPR. [9,10] However, there are few published case reports of TPP as a result of blunt force trauma. [3,6]


    Signs and symptoms of TPP include abdominal distension and fullness. The additional presence of a tympanitic, rigid abdomen, hypotension, dyspnea, and jugular vein congestion can be considered as signs of TPP, requiring immediate management.

    The diagnosis of tension pneumoperitneum should be based physical exam and supported by imaging of the abdomen. Plain films of the abdomen show large amounts of intraperitoneal air. Lateral supine and left lateral decubitus films show the air best. Elevation of the diaphragm or medial displacement of the liver, called the “saddlebag sign” is suggestive of tension physiology.[1] The viscera may appear more distinct as they are outlined by the air tissue interface as in the double-wall sign (the visualization of the outer wall of bowel loops caused by the presence of extraluminal and intraluminal gas). Another radiographic sign of a large pneumoperitoneum is football sign - the intraperitoneal air outlines the abdominal cavity and the falciform ligament appears like the laces of a football.

    With this said, plain films of the abdomen are rarely obtained in the setting of trauma. If hemodynamically stable, the patient is imaged using computed tomography (CT scan) which will show posterior liver compression by superiorly located free air. However, because CT scanning is contraindicated in the hemodynamically unstable patient, the diagnosis may have to rest on the clinical presentation and/or portable plain films. It can be confirmed by needle decompression or paracentesis with a rush of air and improvement of hemodynamic stability. [7]
    Treatment of tension pneumoperitoneum depends on the stability of the patient. If the patient is acutely unstable with labile blood pressures and signs of shock, treatment is emergent needle decompression using a 14g angiocatheter. There are no large trials that recommend a specific location based on success and/or safety rates. However, several small case series suggest using the same sites for decompression: two centimeters below the umbilicus in the midline (through the linea alba) or five centimetres superior and medial to the anterior superior iliac spines on either side. [8]. If the patient is stable, a paracentesis catheter/drain can be placed. The definitive treatment is to determine what initially caused the air accumulation, which may necessitate an exploratory laparotomy. It should be noted that a nasogastric tube turned to suction is unlikely to evacuate the pneumoperitoneum due to the ball and valve mechanism that created it initially. [3]


    Take-home Points: 
    -Pathophysiology and treatment is similarly to pneumothorax, it can lead to cardiovascular collapse, respiratory failure, and eventually death if untreated. Unstable patients should be recognized on exam, however x-ray and CT have utility based on stability. Decompression is the treatment and can be performed with an angiocath placed two centimeters below the umbilicus in the midline. 


    References:
    [1] Lin B, Tension Pneumoperitoneum. The Journal of Emergency Medicine, Vol. 38, No. 1, pp. 57–59, 2010.
    [2] Khan ZA. Conservative management of tension pneumoperitoneum. Ann R Coll Surg Engl. 2002 May;84(3):164-5.
    [3] Ogle JW Tension Pneumoperitoneum after Blunt Trauma. The Journal of Trauma: Injury, Infection, and Critical Care. 1996 Nove; 41(5): 909-911.
    [4] Falkenburg C. Ein Fall von Gasansammlung in der freien Bauch-Hohle. Dtsch Z Chir 1913;124: 130-6.
    [5] Olinde A, Carpenter D, Maher J. Tension pneumo-peritoneum. Arch Surg 1983;118:1347-50.

    [6] Ferrera PCChan L. Tension pneumoperitoneum caused by blunt trauma. Am J Emerg Med. 1999 Jul;17(4):351-3.
    [7] Yakobi-Shvili RCheng D. Tension pneumoperitoneum--a complication of colonoscopy: recognition and treatment in the emergency department. J Emerg Med. 2002 May;22(4):419-20.
    [8] Fu KIshikawa TYamamoto TKaji Y. Paracentesis for successful treatment of tension pneumoperitoneum related to endoscopic submucosal dissection. Endoscopy. 2009;41 Suppl 2:E245.
    [9] Williams DTManoochehri PKim HT. Tension pneumoperitoneum. Emerg Med J. 2014 Nov;31(11):943.
    [10] Mills SAPaulson DScott SMSethi G. Tension pneumoperitoneum and gastric rupture following cardiopulmonary resuscitation. Ann Emerg Med. 1983 Feb;12(2):94-5.
    Submitted by Decompression Danny Kolinsky, PGY-2
    Edited by Louis Jamtgaard, PGY-3. @Lgaard
    Faculty review by Rebecca Bavolek

    Hot bullet, dirty wound?

    Clinical scenario:  You are working in the emergency department when a car pulls up, dropping off an otherwise healthy male who has suffered a gun shot wound (GSW) to left shoulder.  He says that he was in the rear passenger seat driving around with friends and "minding his own business" when he heard multiple gun shots.  He felt immediate pain in his left shoulder.  A full exam reveals two wounds to the left shoulder and nowhere else.  The patient has bilateral breath sounds and his left arm is neurovascularly intact.  X-rays demonstrate no pneumothorax, but the patient has a comminuted left scapular fracture:

    You update the patient's tetanus,  administer pain control, and call Orthopedics.  The orthopedist on call asks that the patient receive prophylactic antibiotics. An ardent defender of antibiotic stewardship, you wonder if antibiotics are necessary.  Is it possible that the heat exposure that comes with firearm discharge sterilizes a contaminated bullet?  Do prophylactic antibiotics decrease the chance of infection?

    Literature Review:
    Question 1:  Does the heat of firearm discharge sterilize a contaminated bullet?
    Image source: http://pixshark.com/
    A study by Thoresby and Darlow from 1967 simulated GSWs  using a series of gelatin models, contaminated bullets, and contaminated overlying “clothes”[1].   There were 3 “series” of testing. The first fired bullets contaminated with Serratia marcescens into a gelatin block. The second fired sterile bullets shot through pieces of military fatigues inoculated with Serratia overlying the entrance or exits side of the gelatin (with a piece of foil in between the cloth and gelatin to avoid direct transmission). The third fired bullets through an aerosolized cloud of Serratia in front of the gelatin block.  Significantly, there was bacterial growth along the bullet track in the gelatin in all three series (except for their respective controls). This suggests that bullets are not sterilized by heat upon discharge of the gun. Furthermore, it demonstrates that bacteria were drawn into the cavitation space via vaccum forces in series in which inoculated cloth was placed on the exit site.



    In a follow-up study carried out by Wolf et. al  in 1978, the authors fired S. aureus tipped bullets from a sterilized gun into sterilized sand [2]. Cultures were obtained from the gun barrel, sand, and bullets prior to start of the experiment and were all negative. Cultures of the contaminated bullets and gun barrels were positive for Staph aureus after they had been fired.  Thus, the contaminated bullets were not sterilized upon discharge of the gun.

    A 1982 study used a dog model (cringe!) in which bacteria (Serratia marcescens)-inoculated cloth was placed on the entrance or exit side of the animal prior to gun discharge[3]. When compared to control animals (no inoculated cloth was placed), bacteriological examination demonstrated primary bacterial contamination of bullet wounds immediately after the shot. It was verified that there were two main mechanisms of primary bacterial contamination: (1) The bacteria were sucked into the wound by negative pressure of the temporary cavity at both entrance and exit sides, and (2) bacteria were carried into the wound tract by contaminated bullet itself.

    Question 2: Are low velocity gun shot wounds with corresponding fractures considered open fractures and do antibiotics decrease the risk of infection?

    In order to answer this question, one must understand that not all fractures caused by gunshot injuries are created equal. These wounds are classified by bullet velocity which is a function of firearm: low-velocity, high-velocity, or shotguns. Bullets with a muzzle velocity less than 2000 feet per second generally are defined as low-velocity. Bullets with a muzzle velocity greater than 2000 feet per second are classified as high-velocity. Examples of muzzle velocities of firearms are given in the table below. There is a general consensus that fractures caused by high-velocity weapons, shotguns, or intra-articular fractures should be treated with prophylactic antibiotics [4].

      Data source: http://library.med.utah.edu/WebPath/TUTORIAL/GUNS/GUNBLST.html 
    There is a paucity of randomized control trials assessing prophylactic antibiotic use in  gunshot wound - associated fractures.  In one small RCT, patients were randomized to receive IV cefazolin 1g q8 x 24 hours or no antibiotics altogether [5]. Patients that sustained high velocity wounds, wounds caused by shot guns, or required surgical intervention were excluded. A total of 96 patients were enrolled in the study. Only 67 were followed until completed union of the fracture. The 29 who were lost to follow up were equally distributed between study groups. Patients were scheduled to follow up 2 weeks after the original injury and then monthly thereafter. The definition of infection was intentionally broad and included any wound complication including prolonged wound drainage, erythema, localized fluctuance, cellulitis, or expressable drainage. Cultures were sent on drainage. Of the 67 patients with complete follow-up, 32 patients (36 fractures) were treated with antibiotics and the other 35 (37 fractures) were not. A total of 1 infection occurred in each group. Chi-Squared analysis demonstrated no significant difference in infection rates. Thus, it was concluded that prophylactic antibiotics did not significantly reduce the incidence of infection in GSW-related fractures.

    A systematic review to address this question was published Papasoulis et al in 2013 [6]. A search of the MEDLINE database yielded 33 studies that pertained to the study goals. Of these only one was a RCT (the aforementioned Dickey et al article) and 9 were considered higher quality and 17 of any quality (including the 9 high quality studies) that addressed the specific question “Are antibiotics needed for the treatment of these fractures?”.

    Table 2 from Papasoulis et. al. (Reference 6)
    The total percentage of infections in fractures treated with antibiotics was 1.7%, while the infection rate for fractures treated without antibiotic treatment was 5.1%. The difference was not significant with the numbers available (p = 0.17). Inclusion of all studies, including 937 fractures, showed an infection rate of 2.4% when antibiotics were used versus 6.7% without antibiotics. When including the lower quality studies, the difference was significant (p = 0.031). However, in the discussion the authors point out that utilizing the lower quality studies is fraught limitations due to mixed data sets – failure to exclude high velocity injuries, unclear locations of gun shot wound, variable follow up periods.

    Papasoulis et. al.  conclude by conceding the fact that infection after gunshot injuries is a rare complication (1.9% of 1156 fractures in the 23 studies that answered this question). Thus, large numbers of patients would have to be enrolled for a study to show a significant benefit with any intervention in terms of reducing infections in gunshot fractures.  Indeed, a post hoc power analysis of the results based on the higher-quality studies demonstrated a power of only 41%.

    Clinical take home: Contaminated bullets are not sterilized on discharge of the firearm. Bullets traversing contaminated overlying clothes or skin track bacteria or particulate matter into the body tissues directly and by cavitation with result negative vacuum forces.   Despite this, infection after gunshot injury is a rare complication.  The current literature, however limited, suggests that there is no significant advantage of prophylactic antibiotics for non-operative fractures caused by gun shot wounds and the risks/benefits should be considered on an individual patient basis.

    References:
    [1] Thoresby, F. P., & Darlow, H. M. (1967). The mechanisms of primary infection of bullet wounds. British Journal of Surgery, 54(5), 359-361.

    [2] Wolf, A. W., Benson, D. R., Shoji, H. I. R. O. M. U., Hoeprich, P. A. U. L., & Gilmore, A. L. A. N. (1978). Autosterilization in low-velocity bullets. The Journal of trauma, 18(1), 63-63.

    [3]Tian, H. M., Huang, M. J., Liu, Y. Q., & Wang, Z. G. (1982). Primary bacterial contamination of wound track. Acta chirurgica Scandinavica. Supplementum, 508, 265-269.

    [4] Simpson, B. M., Wilson, R. H., & Grant, R. E. (2003). Antibiotic therapy in gunshot wound injuries. Clinical orthopaedics and related research, 408, 82-85.

    [5] Dickey, R. L., Barnes, B. C., Kearns, R. J., & Tullos, H. S. (1989). Efficacy of antibiotics in low-velocity gunshot fractures. Journal of orthopaedic trauma, 3(1), 6-10.

    [6] Papasoulis, E., Patzakis, M. J., & Zalavras, C. G. (2013). Antibiotics in the Treatment of Low-velocity Gunshot-induced Fractures: A Systematic Literature Review. Clinical Orthopaedics and Related Research®, 471(12), 3937-3944.


    Submitted by Daniel Kolinsky, PGY-2
    Edited by Maia Dorsett @maiadorsett, PGY-3
    Faculty Reviewed by H. Phil Moy

    Antibiotics for Mandible Fractures?

    Clinical Scenario:

    You’re working a busy Saturday overnight, and the traumas are rolling in. You’ve just finished packaging up your patient with an abdominal GSW for the OR, and they’re bringing back a new patient before the stretcher is even flipped over. He’s a 25 year-old male, presenting to the ED after being in an altercation with some friends of friends. He was hit in the face during the fistfight. He is complaining of left-sided jaw pain and facial swelling. He is able to open his jaw to a reasonable degree, but uncomfortably. There is no apparent intra-oral injury. CT max/face shows multiple minimally-displaced fractures of the left mandibular ramus and paramental region.

    Luckily for you the ENT consult resident is still in the department from seeing your last patient with a complicated ear lac. She evaluates the patient with her senior and looks over the images. The patient will need surgical repair, but is OK for discharge with close pre-op follow-up next week. They recommend mouthwash, nasal spray, analgesia, and antibiotics.

    Clinical question:

    When are prophylactic antibiotics indicated in mandibular fractures, and how effective are they are preventing infection?

    3D CT recon of minimally-displaced mandible fractures. Image from MD Consult.




    Literature review:

    The use of antibiotics for mandible fractures has been common practice for some time, based on the assumption that such fractures are at high risk of infection due to contamination with oral flora. However, like many dogmatic practices, it appears the initial evidence upon which the “standard practice” is based is sorely lacking [1]. 

    A recent systematic review of 31 studies including a total of 5,437 patients published in the Journal of Oral and Maxillofacial Surgery in 2011 found that the overall evidence to support the use of prophylactic antibiotics in mandible fractures is of poor quality [1]. Only 9 of the included studies were RCTs, including 974 patients. The study author laments numerous methodological shortcomings of these RCTs – all had relatively small cohort sizes, none included power calculations, 7/9 RCTs did not describe randomization method, none reported allocation concealment, only one study reported an intention-to-treat analysis, and none reported NNT figures. 

    The author found it impossible to perform any quantitative analysis due to heterogeny of study design and poor quality of included studies. For example: only 10/31 studies included information on time from injury to operative management, 13/31 studies did not describe the type of antibiotic used, half of studies did not describe route of administration of duration of course, and 23/31 studies did not report dose of antibiotic used! Significant heterogeny was also found between the types of fractures included, the types of surgical repairs performed, and the types of antibiotic used.

    Five of the 9 included RCTs concluded that antibiotics were effective in preventing infection. However, the rates of infections varied widely between included studies – from 4.5-62% in untreated groups and 1.9-29% in treated groups, limiting applicability of those conclusions.

    The study author reports that there may be some signal indicating antibiotics are superior to nothing in terms of preventing infection, but concludes:

    “Even then, we are not sure which antibiotic to use, we do not know best route of administration, we are not confident about duration of course, and we have very limited information about the optimal dosage. Even worse, we do not have the slightest idea about how many patients we need to treat with prophylactic antibiotics to prevent a complication, and there is no clue about how much this costs the health care spectrum. Therefore, even in this very optimistic scenario, the available evidence is not sufficient to support a standard protocol for the use of prophylactic antibiotics in the treatment of mandible fracture.”

    Recommendations for post-operative antibiotics have also become more conservative in recent years. A study group in Switzerland conducted an RCT comparing 24hrs of post-op IV antibiotics only vs post-op IV antibiotics followed by a 5-day PO antibiotic course [2]. It was designed as a pilot study and only included 59 patients, but they found no significant differences in incidence of infection between the two groups.

    Another recent retrospective review of 197 patients who underwent operative repair of mandible fracture, published by a group at St. Louis University, found that advanced patient age was the only statistically significant difference in infected and uninfected groups [3]. Injury severity score, fracture type, duration of antibiotic course, and antibiotic type did not differ significantly between the two groups. One primary limitation of this study is the low rate of the primary outcome (only 9 post-op infections occurred).

    Take-home:

    - There is insufficient evidence to strongly support or discourage the routine use of prophylactic antibiotics in closed mandible fractures.

    - Signal from some studies indicating possible benefit of antibiotics warrants further investigation in the form of a well-designed, adequately-powered, placebo-controlled RCT.

    References:

    1) Kyzas PA. Use of antibiotics in the treatment of mandible fractures: a systematic review. Journal of Oral and Maxillofacial Surgery 2011;69(4):827-32.
    2) Schaller B, Soong PL, Zix J, Iizuka T, Lieger O. The role of postoperative prophylactic antibiotics in the treatment of facial fractures: a randomized, double-blind, placebo-controlled pilot clinical study. Part 2: mandibular fractures in 59 patients. Br J Oral Maxillofac Surg 2013;51:803-7.
    3) Hindawi YH, Oakley GM, Kinsella CR, Cray JJ, Lindsay K, Scifres AM. Antibiotic duration and postoperative infection rates in mandibular fractures. Journal of Craniofacial Surgery 2011;22(4):1375-7.

    Submitted by Aurora Lybeck, PGY-3.
    Edited by C. Sam Smith, PGY-3.

    Faculty reviewed by Chris Brooks. 

    ...And We All Fall Down... Eventually : Nonpharmacologic pain management for hip fractures in the elderly?

    Your patient is an elderly male with history of dementia and multiple medical comorbidities who is sent to the emergency department after a fall from standing. He complains of left hip pain and his X-rays demonstrate a comminuted intertrochanteric left hip fracture. Since the elderly and demented constitute an at-risk population for inadequate analgesia as well as increased risk of fall, respiratory depression and delirium from polypharmacy, you wonder what nonpharmacologic pain control interventions may supplement your pain control management for this patient?


    Clinical question: 

    Are nonpharmacologic pain control interventions effective in treating pain associated with hip fracture? Do nonpharmacologic pain control interventions reduce the need for opiates in patients with hip fracture?

    The Literature

    Several studies have examined the efficacy of skin traction (foam boot connected to weight via pulley) versus position of comfort (pillow support) for pain relief in patients with various hip fractures. In two randomized studies, skin traction showed no benefit over pillow support:
    The first study, published in 2001, was a randomized study enrolling 100 participants. They compared skin traction with a 5lb weight versus pillow support. The authors found that patients who were treated with pillow support required less pain medication and reported statistically significantly lower pain scores prior to surgery (after overnight stay awaiting operative intervention) than their traction treated counterparts (p 0.04). They had an average reduction of pain score of 2.82 points versus a reduction of 1.76 points. The average age of patients in the study was 78 and nearly half had intertrochanteric hip fractures (other half were femoral neck fractures). The study was limited in that they excluded demented patients in their study as they were felt unable to demonstrate adequate understanding of the pain scale and reliably report pain scores.
    The second study, released in 2010, included 108 patients randomized to either weighted traction, unweighted traction apparatus or pillow support. Similarly, they observed no difference in pain control between pillow and weighted traction. However, unweighted traction had a statistically significant improvement in pain control compared to the other two. They attributed this to a placebo effect as it provided no actual support of the fracture fragments and did not restrict movement.
    Neither study reported negative outcomes associated with pillow treatment, however both observed minor negative outcomes with skin traction either weighted or unweighted. These included blistering, pressure sores and neurapraxia.

    Take home: 

    - At least two studies demonstrate no improvement in pain control by employing skin traction over pillow support. 
    - Moreover, while the pillow group had no reported negative outcomes related to treatment, the skin traction groups in both studies reported wounds, blistering, nerve compression, and pain with application of the treatment. 
    - In this population with advanced age, comorbid illness, and potentially limited ability to sense or communicate discomfort with a boot, these minor problems could develop important long term sequelae.
    - My treatment plan for the next elderly hip fracture: Pillow support + adequate pharmacologic analgesia + consideration for local nerve blocks. 

    References:
    1) Rosen, JE et al, “Efficacy of preoperative skin traction in hip fracture patients: a prospective, randomized study,” 2001. Journal of Orthopedic Trauma. Vol. 15(2) 81-85.
    2) Sayqi, B et al, “Skin traction and placebo effect in the preoperative pain control in patients with collum and intertrochanteric femur fractures.” 2010 Bulletin of the NYU Hospital for Joint Diseases. Vol. 68(1) 15 - 17.


    Contributed by Sara Manning, PGY-3

    Blunt Abdominal Trauma in Pediatric Patients: A Clinical Decision Rule

    A school-age child was brought to the ED by the mother following involvement in an MVC during which the child was restrained with a lap belt.  The child initially complained of abdominal pain while eating, but currently has no complaints, stable vital signs, and a benign abdominal exam.  The mother is concerned and wonders if her child should get imaging.  This prompts you to investigate whether there are any evidence based clinical decision rules for imaging in pediatric blunt abdominal trauma.

    Clinical question: 

    Do all children with blunt abdominal trauma necessitate abdominal imaging?  Is there a clinical decision rule that can help guide physician and parent shared-decision making when weighing risks vs benefit in evaluation of pediatric patients following blunt abdominal trauma?

    Literature:

    Injuries secondary to blunt abdominal trauma contribute to a large degree of morbidity in the pediatric patient population.  In assessing these patients following trauma, CT scans have become the reference standard for diagnostic of traumatic injury.  However, we must also weigh the risk of exposing patients to increased dosage of radiation and increasing their risk of radiation-induced malignancy.  This is especially true in the pediatric population given their rapidly developing bodies as well as their propensity to have a continued lifetime of exposure to medical radiation through future diagnostics.  

    Clinicians, especially those not accustomed to regularly seeing pediatric patients, trauma patients, or more specifically pediatric trauma patients, often (anecdotally) err on the side of obtaining advanced imaging to assess patients following blunt abdominal trauma.  Dr. James Holmes and his colleagues in the PECARN (Pediatric Emergency Care Applied Research Network) group derived a clinical decision rule to help guide decision making when considering imaging in the pediatric patients.  Using a large, prospective study in 20 EDs, they identified a 7 point rule based solely on history and physical data to help risk stratify the pediatric blunt abdominal patient.  In patients who have no evidence of abdominal wall trauma or a seatbelt sign, a GCS >14, no abdominal tenderness on PE, no thoracic wall trauma, no complaint of abdominal pain, no absence or decreased breath sounds, and no vomiting, the risk of intra-abdominal injury requiring intervention is extremely low (0.1%).  

    While these findings require external validation before likely widespread use, they have benefit for current ED practitioners for several reasons.  First, they used a patient oriented outcome of injury requiring intervention rather than a diagnostic outcome of any intra-abdominal injury, so that some patients who perhaps had injury but went on to have a stable clinical course and never received imaging were not a source of bias.  Secondly, their 7 findings were based solely on history and physical findings, something that is available to any clinician regardless of location or resources.  This eliminated the exclusion of validity to centers able to perform FAST scans or obtain more rapid lab results.  It also likely further decreased the “miss rate” for significant intra-abdominal injury when the clinical decision rule is supplemented by these diagnostic studies.  Finally, their rule is not meant as a hard “rule” to force a physician’s hand in obtaining a CT on a patient who carries 1 or 2 of their H&P risk factors.  It is meant to guide the conversation and critical decision process in weighing the radiation exposure risk versus the inherent injury risk when deciding how to continue the workup of the presenting child.  0.1% is a lower risk of injury the risk of a radiation induced malignancy in a young child.  However, as more risk factors accumulate, that may mitigate the difference in risk percentage, increasing the possible benefit of obtaining the CT.

    Take home:

    All patients, especially pediatric patients are sensitive to the ionizing radiation of medical imaging.  Risk stratifying pediatric patients with decreased likelihood of significant intra-abdominal injury can help physicians to have informed discussions with patients and their guardians and help to decrease the number of CT scans ordered on low risk patients and their exposure to unnecessary radiation.

    References:

    1) Holmes, JF, et al.  Identifying Children at Very Low Risk of Clinically Important Blunt Abdominal Injuries.  Annals of Emergency Medicine.  2013. 62: 107-16

    Kindly contributed by Michael Galante, PGY-3.

    Does a cervical seatbelt sign mandate advanced imaging?

    You are working in the emergency department when EMS brings in a middle aged female who was the restrained driver in a low speed head-on MVC. In the emergency department, she is slightly hypertensive and complaining of generalized stiffness. Her physical exam (including C-spine exam and neurologic exam) is unremarkable with the exception of an abrasion to the left side of her neck without surrounding hematoma concerning for a cervical seat belt sign.

    Clinical Question:


    In this otherwise well appearing patient you wonder – what is the best course of action? Does the physical finding of a cervical seat belt sign warrant additional imaging for vascular injury, such as a CT-A?

    Literature:


    One study that addressed this question was a retrospective review of patients who received neck CT angiograms based on the presence of a seatbelt sign alone at a Level I trauma center from 2008-2010. Over this time period, 418 patients underwent a CT-A. Eleven patients had positive vascular findings, two with blunt carotid injury (BCA) – giving an overall frequency vascular injury of 2.6%. Importantly, all of the patients who were found to have vascular injuries had a cervical spine fracture, rib fracture, thoracic spine fracture, facial fracture, skull fracture, large hematoma on the neck or a combination of the above injuries. The correlation between seatbelt sign and positive CT-A finding was overall very weak (r = .007). The above findings lead the authors to reasonably conclude that CT-A of the neck vascular injury can be “safely reserved for patients with a seatbelt sign and obvious injuries on physical examination and/or positive findings on standard trauma imaging.”

    A second study prospectively evaluated trauma patients with cervical or thoracic seatbelt signs at a level I trauma center over a 17 month period. Out of 131 trauma pts with cervical or thoracic seatbelt signs, four (3%) were found to have carotid artery injuries. The presence of a carotid injury was strongly associated with a GCS < 14 (p< 0.0003), ISS > 16 (p < .0001), and the presence of a clavicle or first rib fracture (p < .0037). No vascular injuries were identified in patients with thoracic-only seatbelt signs. Each of the four patients had at least one identifiable significant injury ranging from scalp laceration + extremity fracture to clavicle + bilateral superior rib fractures. The authors of this study concluded that the cervical-thoracic seatbelt sign combined with an abnormal physical examination is an “effective screening combination for cervico-thoracic vascular injury.”

    Take Home:


    CT-angiogram is not necessarily indicated based on the finding of a cervical seatbelt sign alone in the absence of significant hematoma, neurologic symptoms, or other traumatic injuries.

    References:

    1) Dhillon, Ramandeep Singh, et al. "Seatbelt sign as an indication for four-vessel computed tomography angiogram of the neck to diagnose blunt carotid artery and other cervical vascular injuries." The American Surgeon 79.10 (2013): 1001-1004.
    2) Rozycki, Grace S., et al. "A prospective study for the detection of vascular injury in adult and pediatric patients with cervicothoracic seat belt signs." The Journal of Trauma and Acute Care Surgery 52.4 (2002): 618-624.