The Evolving Management of Venous Bullet Emboli: A case series and literature review

Injury, Int. J. Care Injured 42 (2011) 441–446

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Review

The Evolving Management of Venous Bullet Emboli: A case series and literature review Keith R. Miller *, Matthew V. Benns, Jason D. Sciarretta, Brian G. Harbrecht, Charles B. Ross, Glen A. Franklin, Jason W. Smith University of Louisville, Department of Surgery, Louisville, KY, United States

A R T I C L E I N F O

A B S T R A C T

Article history: Accepted 3 August 2010

Bullet emboli are an infrequent and unique complication of penetrating trauma. Complications of venous and arterial bullet emboli can be devastating and commonly include limb-threatening ischaemia, pulmonary embolism, cardiac valvular incompetence, and cerebrovascular accidents. Bullets from penetrating wounds can gain access to the venous circulation and embolise to nearly every large vascular bed. Venous emboli are often occult phenomenon and may remain unrecognised until migration leads to vascular injury or flow obstruction with resultant oedema. The majority of arterial emboli present early with end-organ or limb ischaemia. We describe four separate cases involving venous bullet embolism and the subsequent management of each case. Review of the literature focusing on the reported management of these injuries, comparison of techniques of management, as well as the evolving role of endovascular techniques in the management of bullet emboli is provided. ß 2010 Elsevier Ltd. All rights reserved.

Keywords: Bullet emboli Endovascular Penetrating trauma

Contents Introduction . . . . . . . . . . . . . . Case reviews . . . . . . . . . . . . . Case 1 . . . . . . . . . . . . . Case 2 . . . . . . . . . . . . . Case 3 . . . . . . . . . . . . . Case 4 . . . . . . . . . . . . . Discussion . . . . . . . . . . . . . . . Conflict of interest statement References . . . . . . . . . . . . . . .

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Introduction Penetrating gunshot wounds present a wide range of unique injury patterns. Commonly, by ascertaining the anticipated tract of the projectile, reasonable estimates of the associated injuries may be predicted. Although rare, bullet emboli present an exception to the predicted injury pattern and pose a challenging diagnostic and therapeutic dilemma. Intravascular bullet migration through the arterial or venous circulation has been sporadically reported in the

* Corresponding author at: Department of Surgery, University of Louisville, 550 S. Jackson Street, Louisville, KY 40292, United States. Tel.: +1 317 442 1412. E-mail addresses: [email protected], [email protected], [email protected] (K.R. Miller). 0020–1383/$ – see front matter ß 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2010.08.006

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441 442 442 442 443 443 443 445 446

literature. Due to the relative scarcity of this event, no management guidelines are universally accepted. It is generally agreed that arterial emboli should be extracted and both open and endovascular techniques have been used. Venous emboli are usually asymptomatic with the majority of those reported lodging in the right heart or pulmonary arterial tree. Management guidelines for venous emboli are less uniform and both extraction and observation have been described.26,46 Evolution of endovascular techniques for bullet extraction has anecdotally decreased morbidity by decreasing the need for thoracotomy, sternotomy and cardiopulmonary bypass, previously required for operative access and removal of centrally lodged bullet emboli. We present four cases of venous bullet embolism and their subsequent management from level one trauma centres in an attempt to better characterise the treatment and diagnosis of these challenging injuries.

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[(Fig._2)TD$IG]

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Case reviews Case 1 A 22-year-old male presented after sustaining a large calibre gunshot wound to the left chest. The patient was alert, responsive, and haemodynamically stable at presentation but appeared pale and diaphoretic. He had undergone needle decompression of his chest in the field secondary to decreased left-sided breath sounds. Upon presentation, a left-sided thoracostomy tube was inserted with evacuation of 700 ml of blood. A chest X-ray revealed clear lung fields bilaterally and a foreign body in the midline at the level of the diaphragm as well as an old bullet lodged in his right chest wall (Fig. 1). A Focused Assessment with Sonography for Trauma (FAST) scan was performed which demonstrated free intraperitoneal fluid in both the right upper and left upper quadrants and the patient was taken emergently for exploratory laparotomy. Upon exploration, it was noted that the bullet had traversed the left hemi-diaphragm resulting in a splenic laceration and multiple enterotomies. Following splenectomy, a left-sided retroperitoneal haematoma was identified and exploration revealed an extensive left external iliac vein injury that required ligation. No bullet was discovered intra-abdominally on exploration. A temporary closure was performed and the patient was transferred to the intensive care unit for further resuscitation. After stabilisation of the patient, a CT of the chest revealed that the bullet was lodged intravascularly within the suprahepatic vena cava (Fig. 2). Forty-eight hours later, following completion of resuscitation and definitive abdominal closure, the patient underwent transluminal snare removal of the bullet from the cavo-atrial junction through a percutaneous left femoral vein approach under fluoroscopic guidance (Fig. 3). A left superficial femoral venotomy was performed to assist with the extraction of the large calibre bullet.

Fig. 2. This CT scan obtained after initial operative exploration demonstrated the bullet located within the suprahepatic vena cava.

Case 2

middle lobe and right lower lobectomy with ligation of the right inferior pulmonary artery. Subsequent chest X-ray identified the bullet located centrally and chest CT confirmed its location as within the right ventricle. Presumably, the bullet migrated from the pulmonary artery to the right ventricle as no cardiac injury was identified. After patient resuscitation and stabilisation, an endovascular transluminal snare of the bullet was accomplished via a right femoral venous approach. The bullet was removed after

[(Fig._1)TD$IG]

A 32-year-old female sustained a gunshot wound to the right chest. The patient presented in extremis to the Trauma Center. Breath sounds were absent on the right and a tube thoracostomy was performed evacuating 1800 ml of blood. The patient was taken for emergent right anterolateral thoracotomy where a peripheral injury to the right middle lobe as well as a large central injury to the right lower lobe of the lung was quickly identified. Additionally, a right inferior pulmonary artery injury was identified. The patient underwent wedge resection of the right

Fig. 1. This chest X-ray obtained upon presentation demonstrated a bullet located at the level of the diaphragm. A prior gunshot wound resulted in a bullet in the subcutaneous tissue in the right chest.

[(Fig._3)TD$IG]

Fig. 3. A percutaneous left femoral approach was utilised in order to snare the bullet and direct it to the femoral vein for removal.

[(Fig._4)TD$IG]

[(Fig._6)TD$IG]

K.R. Miller et al. / Injury, Int. J. Care Injured 42 (2011) 441–446

443

Fig. 4. Wire snare via a right internal jugular approach secured the bullet within the right ventricle.

Fig. 6. Proximal control was achieved on the inferior vena cava and the bullet was retrieved through a cavotomy.

sequestering it within a 20 Fr vascular sheath. Percutaneous closure of the venotomy was accomplished without difficulty.

abdomen. The colon injury was then resected and temporary abdominal closure was instituted due to diffuse coagulopathy. On post-operative chest X-ray a bullet was identified at the level of the diaphragm in the right abdomen. On second look laparotomy the right upper quadrant was explored and no injury was identified. The patient was given an end colostomy and his abdomen was closed. A repeat chest X-ray post-operatively demonstrated a bullet lying centrally in the area of the cardiac silhouette. Chest CT demonstrated the bullet to be resting within the right atrial appendage. This was subsequently removed via endovascular snaring via a right internal jugular approach. Percutaneous closure of the venotomy to extract the projectile was performed.

Case 3 A 23-year-old male sustained gunshot wounds to multiple extremities as well as a single transpelvic gunshot wound. The patient presented awake but haemodynamically labile. The patient was resuscitated and the digital rectal exam demonstrated gross blood. The patient was taken for emergent laparotomy which demonstrated a large central retroperitoneal haematoma as well as a low lying colon injury. After rapid control of enteral contamination, the central haematoma was explored revealing a large injury to the inferior vena cava at the bifurcation of the iliac veins requiring ligation of both the inferior vena cava and bilateral proximal iliac veins. The bullet could not be located within the

[(Fig._5)TD$IG]

Case 4 A 25-year-old man presented to the emergency department after sustaining a single gunshot wound to the mid-abdomen. The patient was haemodynamically unstable and emergently taken to the operating room for exploration. On exploration, the patient was noted to have multiple enterotomies and a large central retroperitoneal haematoma. Upon opening the haematoma, an inferior vena cava injury was identified and subsequently ligated above the iliac bifurcation. The patient was closed with a temporary abdominal closure and taken to the ICU for further resuscitation. A post-operative abdominal film revealed a bullet in the right upper quadrant overlying a liver injury. Forty-eight hours later a chest radiograph showed a bullet within the right ventricle. The patient was taken back to the OR for planned re-exploration and utilising a percutaneous right internal jugular approach, the bullet was snared (Fig. 4) and carried into the proximal inferior vena cava (Fig. 5) and extracted through a cavotomy (Fig. 6). The above four cases demonstrate the complexity of diagnosing venous bullet emboli in patients sustaining gunshot wound injuries. These four cases were accumulated over 17 years in a busy Level One Trauma Center, confirming the relative infrequency of bullet emboli. Discussion

Fig. 5. The snare was then utilised to transport the bullet down the vena cava into the operative field.

The first case report of foreign body embolus is attributed to Thomas Davis in 1834 and involved not a bullet, but a wooden

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fragment embolising from the venous circulation to the right ventricle.7 Sporadic case reports have followed in the literature. The diagnosis of bullet embolism is often difficult and is commonly the result of one of three observations. First, an incongruent number of entry and exit wounds without intra-operative or radiographic confirmation of the presence of the bullet within the appropriate cavity should raise suspicion. Secondly, a radiograph demonstrating a bullet in a body cavity or anatomical location inconsistent with the presumed trajectory should prompt further investigation. Alternative explanations for this finding include missed wounds or a prior history of gunshot wounds. Finally, as was the situation with our third case, serial radiographs demonstrating a ‘‘moving’’ foreign body should raise suspicion. These observations are difficult to make in real time in the haemodynamically unstable patient and are often discovered during post-operative investigation following resuscitation and stabilisation of the patient. Bullet emboli are initially characterised as arterial, venous, or paradoxical. The majority (80%) are arterial in nature.32 Although there are exceptions, generally arterial emboli result in distal ischaemia, are symptomatic, and thus discovered early. There are rare exceptions. Adegboyega described an abdominal gunshot wound resulting in an arterial embolus originating in the abdominal aorta that was subsequently discovered within the left popliteal artery. The patient was initially asymptomatic but later (14 months after the initial injury) presented with left lower extremity swelling and pain. He was found to have an embolic bullet fragment within his posterior tibial artery and later required above-the-knee amputation.1 More commonly, peripheral arterial embolisation results in decreased or absent distal pulses or changes in neurologic status if the carotid or cerebral vasculature are involved. de Andrade et al. reported a 31-year-old man who sustained a gunshot wound to the neck who presented with a Glasgow Coma Scale of 7 and complete right hemiplegia with no evidence of intracranial penetration. A carotid angiogram demonstrated an embolic fragment occluding the left middle cerebral artery. No intervention was undertaken and the patient’s neurologic status later declined.14 Venous bullet emboli can gain entry to the venous circulation from nearly any point of injury. Reports have included injuries sustained to the head,21 neck,6,9 extremities,3,7,16,41 chest8,18,28,31,45,49 and abdomen.26,37–39 Most foreign bodies travel in the direction of blood flow but retrograde emboli, due to the effect of gravity, have been reported in as many as 15% of injuries.4 Complications of venous bullet emboli are numerous and include cardiac valvular destruction, endocarditis, sepsis, venous thrombosis, thrombophlebitis, dysrhythmias, and severe hypoxia secondary to pulmonary arterial emboli. Many of these complications are discovered months to years after the initial injury. Most venous embolic foreign bodies eventually migrate to the right ventricle or pulmonary arterial tree. Lundy et al. conducted a review of retained cardiac missiles after penetrating trauma (including both embolic and direct penetrating wounds) and reported a complication rate of 13% for missiles retained within the right heart.30 These complications included a patient presenting with dysrhythmia 4 years after the initial injury from a right ventricular bullet embolus49 and another patient with a bullet embolus to the right ventricle with resultant tricuspid valve destruction and insufficiency.18 Both of these patients eventually underwent bullet extraction. The final pattern of injury and paradoxical bullet emboli, have been infrequently reported.12,45 By definition, paradoxical emboli originate from a venous point of entry and subsequently move to the arterial circulation. Access is gained through either an

intracardiac defect or through a traumatic communication created by the missile (areriovenous fistula). Flow through right-to-left shunts such as patent foramen ovale is increased with positive end expiratory pressure mechanical ventilation which may contribute to this phenomenon.13 Corbett describes a case where an 18-year-old man sustained gunshot wounds to the flank and groin and was found to have a bullet within the left common femoral artery. The proposed scenario involved the bullet entering the retrohepatic vena cava and moving to the right heart, through a patent foramen ovale, and then to the arterial circulation. The bullet was extracted through an arteriotomy followed by primary anastamosis.12 A review of cases of venous bullet emboli reported in the literature from 1987 to 2010 revealed 45 cases from 42 publications. A review by Shannon et al. described injuries occurring before 1987 prior to the refinement of endovascular techniques.46 The entry point for the majority of the missiles in our review was either the chest (12/45), abdomen (9/45), or head and neck (9/45). Although a substantial number were the result of chest trauma, there was a slight edge favouring gunshot wounds sustained below the diaphragm when extremities were included. In addition to these more common injury patterns were cases reported as a result of wounds sustained to the extremities, buttock, flank, and inguinal regions. Injuries were discovered both at the time of presentation and as late as 59 years after the initial injury.6 The majority of venous emboli lodge in the right heart (22/ 45) or the pulmonary arteries (15/45). In addition were the two cases reported with the missile resting within the hepatic vein and solitary cases within the inferior vena cava, popliteal, femoral, and common iliac veins. Again, two cases of paradoxical embolus were reported among those cases reviewed, one of which is described in detail above.12 Management patterns were often dictated by the timing of discovery, anatomical location, and the presence or absence of symptoms. Fifty-eight percent of injuries underwent intervention, most of which were removed through open (18/45), endovascular (6/45), or hybrid open/endovascular (2/45) approaches. Two cases were discovered at autopsy and in the remaining three cases the management was unclear. Many that were removed utilising the open approach were done so during the initial operation whereas most endovascular interventions were done following further stabilisation of the patient. Four open procedures were performed following failed endovascular retrieval. The first endovascular retrieval was reported in 1980 by Hartzler and involved the retrieval of a missile located within the right ventricle.19 Advancements in endovascular techniques have permitted more widespread adoption of this technique. Almost forty percent (3/8) of the interventions for bullet emboli reported since 2007 underwent either an endovascular or hybrid retrieval. More than 30% (14/45) of cases were managed by careful observation with most of these resting within the pulmonary artery in asymptomatic patients. Debate continues as to the most appropriate approach to these asymptomatic patients. Shannon et al. advocated the mandatory extraction of venous bullet emboli discovered early (<6 weeks) but suggested selective observation was adequate in the asymptomatic patient with late discovery.46 This seemed a rational approach at the time of their publication as most cases that were not discovered early were likely asymptomatic and the open operative techniques available were not without significant morbidity. In asymptomatic patients, the final anatomical structure wherein the missile rests appears more important than the timing of the discovery of the injury. Foreign bodies resting in the pulmonary arterial vasculature represent a scenario where the risk of thoracotomy for retrieval might outweigh the morbidity of observation in

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asymptomatic patients. To this point, conservative management was advocated by Kortbeek et al. who in 1992 reviewed 32 cases of pulmonary artery bullet emboli that were observed without complication.26 Although observation may occasionally be appropriate, refinements in endovascular techniques favour missile retrieval in suitable candidates given the low but definable risk of late complications. In conclusion, intravascular bullet emboli present in a variety of ways and the diagnosis is often difficult. We advocate the removal of all arterial emboli. Due to the asymptomatic nature of most venous emboli, management remains less clear. Through interpreting the timing of discovery, presence or absence of symptoms, and anatomical location of the embolus a risk–benefit estimate can guide further management decisions. Endovascular techniques have reduced the morbidity and mortality of bullet retrieval and have shifted the risk–benefit ratio in favour of retrieval of all intracardiac missiles even in the absence of symptoms in order to prevent late complications. The data suggests that pulmonary arterial emboli can be observed in the asymptomatic patient regardless of the timing of discovery in suitable patients unless easily accessible through an endovascular approach (see algorithm). Due to the infrequent nature of these injuries, an individualised approach is warranted with careful consideration of the above factors.

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Conflict of interest statement None declared.

Appendix A Entry site

Diaphragm

Destination

Management

Kortbeek et al.26 Martı´ et al.31 Nazir et al.35 Nagy et al.34 O’Neill et al.37 Panichabhongse et al.38 Schurr et al.45

Chest 1. Abdomen 2. Abdomen 3. Abdomen Chest Chest Abdomen Abdomen Head 1. Neck 2. Inguinal Abdomen Chest Chest Lower extremity Abdomen Abdomen Chest

Above 1. Below 2. Below 3. Below Above Above Below Below Above 1. Above 2. Below Below Above Above Below Below Below Above

Endovascular retrieval 1. Observation 2.Obeservation 3. Open removal Observed PL thoracotomy Sternotomy/CPB Unknown Open 1. Sternotomy/CPB 2. Sternotomy/CPB Observation Unknown Open/Failed endovascular Observation Trans-jugular extraction Observation Ex Lap, open removal w/arteriotomy

Headrick et al.20 Lodder27 Scho¨pf et al.44 Kaushik and Mandal25 Pollak et al.40 Obermeyer et al.36 Luison and Inculet29 Best5 Wales et al.49 Kalimi et al.24

Abdomen Lower extremity Head Lower extremity Inguinal Buttock Chest Buttock Chest Buttock

Below Below Above Below Below Below Above Below Above Below

Right hepatic vein 1. PA 2. PA 3. Right atrium L SC vein ! popliteal vein PA Right atrium PA Right ventricle 1. Right ventricle 2. Right atrium PA SVC ! right ventricle Right ventricle Iliac ! right ventricle RV ! IVC ! RA Right PA L external iliac vein ! PFO ! L common iliac artery IVC ! right ventricle PA PA Iliac vein ! RA Right atrium Right ventricle R Brachiocephalic Vein ! PA Right heart Right ventricle Right ventricle

Lucena and Romero28 Berkan and Gu¨nay3 Corbett et al.12 Bertoldo et al.4 Bett and Walters6 Demirkilic et al.15 Hughes and Vender21 Agarwal et al.2 Bining et al.7 Breeding et al.9 Chen et al.10 Dulic´ et al.16 Ettinger et al.18

Chest Inguinal Inguinal/ Flank Chest Neck Lower extremity Head Neck Flank/lower extremity Neck Flank Lower extremity Chest

Above Below Below Above Above Below Above Above Below Above Below Below Above

External iliac vein Right ventricle IVC ! PFO ! common femoral artery SVC ! iliac ! IVC Right ventricle PA PA PA Right ventricle Right atrium PA PA Right heart

Rehm et al.42 Patel et al.39

Schmelzer et al.43 Va´zquez-Valde´s et al.48 Michelassi et al.33 John and Edmondson23 Van Arsdell et al.47 Colquhoun et al.11

Sternotomy/CPB Observation Unknown Endovascular Observation Observation Observation Transfemoral extraction (EV) Sternotomy w/CPB Observation after failed retrieval, sternotomy/CPB Autopsy Observation Open Thoracotomy Observation/pacemaker Sternotomy/CPB Observation Thoracotomy Sternotomy Sternotomy/endovascular Endovascular Observation Sternotomy/CPB

K.R. Miller et al. / Injury, Int. J. Care Injured 42 (2011) 441–446

446 Appendix A (Continued )

8

Bors et al. Engelgardt et al.17 Raikar et al.41 Jo et al.22

Entry site

Diaphragm

Destination

Management

Chest Head Buttock Head

Above Above Below Above

L BC vein ! right ventricle SVC ! IVC ! femoral vein Hepatic vein PA

Open removal/CPB Autopsy Endovascular Thoracotomy, embolectomy

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