Radiology Case of Interest

Chief complaint: “I stuck something in myself.”

 

History of Present Illness:

A 53 year old male with a past medical history of HCV and psychiatric disorders was brought in by EMS after being found on the floor of a house, reportedly with a screwdriver in the rectum. He reported that he inserted the screwdriver himself three days prior and has since been unable to get up off the floor due to pain and generalized weakness. EMS found him surrounded by urine and feces, but alert and oriented. He was speaking in full but slow sentences. Upon presentation to the resuscitation bay, he was alert and oriented to self, place, and time but febrile, hypotense, tachypneic, and tachycardic. The portable pelvic x-ray is shown here.

 

Physical Exam:

Triage Vitals: Temp 103.0 F, HR 116, RR 22, BP 84/46, SpO2 99% on room air

General: ill-appearing, A+Ox3, in no acute distress

HEENT: Normocephalic, atraumatic. PERRL, EOMI. Airway intact, speaking full clear sentences. No oropharyngeal erythema or edema.

CV: Tachycardic with regular rhythm. No murmurs, rubs, or gallops appreciated.

Pulmonary: Tachypneic. Lungs clear to auscultation bilaterally. No wheezes or rales.

Abdomen: Mildly distended with generalized tenderness. No ecchymoses or erythema. No crepitus.

GU: Generalized erythema to perineum and scrotum with small regions of dark, necrotic-appearing tissue along perineum. Generalized scrotal and perineal tenderness. No crepitus. Penis appears normal, no erythema, no edema, nontender. No foreign object was grossly visible protruding from the anus.

Extremities: 2cm x 1cm open wound in left medial thigh draining purulent fluid with large area of erythema extending to most of scrotum, the perineum, and the right medial thigh. Palpable crepitus in bilateral thighs.

Neuro: CN II-XII grossly intact and symmetric. Moving all extremities spontaneously, though slowly. A+Ox3, speaking in full sentences.

 

Questions:

  1. What potentially life-threatening findings do you see in this radiograph?
  2. How would you resuscitate this patient?

 

Answers:

  1. Evidence of free air within bilateral thighs, concerning for bowel perforation.
  2. Assuming this patient had septic shock based on clinical presentation and initial vitals, give early empiric broad-spectrum antibiotics and IV crystalloid at 30 mL/kg for the first 3 hours. However, given the high suspicion for necrotizing fasciitis, it is imperative to have early surgical evaluation for definitive treatment of debridement in the operating room.

 

Case discussion:

ED course: Due to high concern for sepsis secondary to necrotizing fasciitis and bowel perforation, the patient was started on empiric broad-spectrum antibiotics and IV fluids in the ED and immediately taken to the operating room for exploratory laparotomy and wound debridement.

 

OR course: The patient underwent open foreign body removal with associated left thigh muscle necrotic tissue debridement, partial colectomy, abdominal washout, and end-sigmoid colostomy. He was later taken back to the OR multiple times for bilateral groin and thigh debridements for necrotizing fasciitis, which grew Klebsiella on wound cultures.

 

SICU and floor course: He was continued on clindamycin, vancomycin and ampicillin-sulbactam. The leg and abdominal wounds were managed with vacuum-assisted closure. He was transferred from the SICU to the general surgery floor on day 10 of admission. He later returned to the OR on day 26 for irrigation/debridement and skin grafting of the left lower extremity. Cultures grew Prevotella, Klebsiella, and Staph. haemolyticus. He was discharged from the hospital in stable condition on day 61 of admission with continued outpatient oral fluconazole and vancomycin via PICC.

 

This particular case was time critical, as both the emergency medicine and surgery teams were suspicious of necrotizing fasciitis as one of the potential causes of his septic shock. Rapid resuscitative measures, including starting empiric broad-spectrum antibiotics (given the high likelihood of bowel perforation, as well as possible Fournier’s gangrene, as the source of his septic shock), should be initiated.

 

A common empiric regimen is meropenem IV 1 gram or 25 mg/kg every 8 hours plus clindamycin IV 600mg or 15 mg/kg every 8 hours1. Wound cultures should be obtained as well, as a patient with necrotizing fasciitis will likely have a long hospital course and antibiotic adjustment based on cultures will be critical. Per the sepsis protocol, IV crystalloids should be initiated at 30 mL/kg for the first 3 hours2. Failed blood pressure response to IV fluid resuscitation may warrant placing a central venous catheter in order to give vasopressors. In this particular case, it would be best to place it in the internal jugular or subclavian vein and not the femoral vein, as we want to avoid iatrogenic introduction of the pre-existing infection in the thigh/perineal region to the rest of the body. Draw blood cultures, obtain urinalysis and urine culture, and perform portable chest x-ray to assess for other major sources of infection; if the portable chest x-ray is performed sitting upright, any free air seen under the diaphragm may also help confirm the diagnosis and help guide the surgeons prior to opening up the patient. Obtain an initial lactate to establish an initial value so that the inpatient team can trend the lactate to determine whether the patient is responding appropriately to therapy.

 

The most important measure in treating necrotizing fasciitis remains surgical debridement and necrosectomy. Surgical intervention must be initiated as early as possible, as multiple studies have shown that delays in surgical treatment of necrotizing fasciitis lead to significantly higher mortality rates2. Therefore, in addition to the early resuscitative measures for sepsis mentioned above, another key part in appropriate treatment for this patient is to have surgeons at the bedside in the resuscitation bay for evaluation and expedient transfer to the OR. A recent study strongly suggests that time from admission to initiation of surgery in cases of gastrointestinal perforation associated with septic shock was significantly associated with 60-day outcome. In this study, 55 of the 154 enrolled patients had surgery initiated within two hours and had a 98% sixty-day survival rate. Further delays significantly increased the mortality rate; 0% of the patients who started surgery over 6 hours after admission survived3.

 

In subsequent months after this patient presented to our hospital, this pelvic x-ray was presented to other residents not involved in the case in a vacuum, i.e. no other information about the case was given to them when shown the radiograph. Many of them, especially those in the earlier training years, failed to immediately recognize the presence of free air in the thigh. Understandably, most of them immediately pointed their attention to the obvious foreign object in the abdomen instead of to the free air, which is the more critical and life-threatening finding.

 

This case reminds us to avoid anchoring on the obvious and to be systematic in every single image that we analyze so that we don’t miss a less obvious, but potentially more critical, finding. Many people have different systems or orders that they use when analyzing radiographs to grossly evaluate the entire image. The exact system or order used matters less than a) using one that covers every important feature of the image and b) consistently using that system every single time.

 

Pearls:

Recognize sepsis and septic shock early. Early initiation of broad-spectrum antibiotics and fluid resuscitation at 30 mL/kg for the first 3 hours are critical to decreasing mortality. Trend serial blood lactate levels.

 

In cases of bowel perforation associated with septic shock, time to initiation of surgery is critical to decreasing mortality. Early and aggressive surgical intervention remains the most critical step in management of necrotizing fasciitis.

 

Analogous to missing critical wounds by anchoring on the obvious, distracting injuries, remember to be systematic when analyzing imaging. Establish an ordered system that you use to analyze every single radiograph to minimize the chance of missing critical, time-sensitive findings.

 

Sources:

  1. Misiakos EP, Bagias G, Patapis P, Sotiropoulos D, Kanavidis P, Machairas A. Current concepts in the management of necrotizing fasciitis. Front Surg. 2014;1:36.
  2. Angus DC, Barnato AE, Bell D. A systematic review and meta-analysis of early goal-directed therapy for septic shock: the ARISE, ProCESS and ProMISe Investigators. Intensive care medicine. 41(9):1549-60. 2015.
  3. Roje Z, Roje Z, Matic D, Librenjak D, Dokuzovic S, Varvodic J. Necrotizing fasciitis: literature review of contemporary strategies for diagnosing and management with three case reports: torso, abdominal wall, upper and lower limbs. Word J Emerg Surg (2011) 23(6):46.10.1186/1749-7922-6-46
  4. Azuhata T, Kinoshita K, Kawano D. Time from admission to initiation of surgery for source control is a critical determinant of survival in patients with gastrointestinal perforation with associated septic shock. Critical care (London, England). 18(3):R87. 2014.

By Gordon Chien 2018