Blunt abdominal trauma is not uncommon in Portugal, a country known for its hight number of car accidents. However, small bowel injuries following a blunt abdominal trauma are rare (1%). Additionally, small bowel perforation occur in 0,3% of those patients. Meaning there are a lack of data on the best diagnostic approach and management of a patient suffering from small bowel injury (SBI) after a blunt trauma. Non-operative treatment is gaining acceptance for blunt trauma cases with solid organ injury in hemodynamically stable patients. Is this true for small bowel injuries? Is there any imaging finding that can help us decide between non-operative versus operative treatment? Hmmmm...
Last month, surgeons (my fellow colleagues and me) from the ancient (?) Surgery C Department of Centro Hospitalar e Univesitário de Coimbra - Hospital Geral (Covões), published in International Journal of Surgery Case Reports a case report entitled - "Multiple isolated small bowel perforations following blunt abdominal trauma".
Louro et al report a case of a male patient who suffered a blunt abdominal trauma that caused five small bowel perforations. Why is this case important? At arrival the patient was hemodynamically normal, the abdomen was plain, with diffuse tenderness but without guarding. Chest film showed no pneumoperitoneum, and an abdominal ultrasound revealed a small amount of inter loop fluid. An abdominal CT scan was then performed revealing only an intramural small bowel haemorrhage without pneumoperitoneum. Non-operative treatment seemed to be indicated... However, during the next hour there was an increase in abdominal pain with tachycardia along with sweaty and cold extremities. Diffuse abdominal tenderness and guarding were present. The authors decided to proceed to emergent surgery despite the CT scan negative findings. On laparotomy, five (5) small bowel perforations were evident. They were all repaired with non-absorbable sutures and three drains were left in the abdomen. Patient was discharged home on postoperative day seven, free of symptoms.
Absence of pneumoperitoneum does not exclude SBI.
The authors found the rate of false negatives for SBI when using only CT scan can be as high as 15%. Pneumoperitoneum may not be seen in the case of a temporarily covered perforation, or if only liquid is leaking. This means that the absence of pneumoperitoneum does not exclude small bowel perforation. Some authors suggest that finding intra abdominal liquid without solid organ injury may raise the suspicion of SBI. So... there are no specific imaging findings, and on the other hand time delay between trauma and surgical management is crucial (mortality is 4x's higher in a 24h delay comparing to less than 8h).
First take home message:
Relying only in imaging findings can delay diagnosis and treatment of a small bowel injury.
Louro et al highlight in this paper the importance of clinical evaluation, and how it must be serial. A trauma patient must be periodically evaluated, recording symptoms, physical examination, and vital signs. In the case published by the authors was the serial clinical evaluation that conducted the surgical team to the decision of an emergent laparotomy. CT scan was negative but clinical evaluation was not.
Second take home message:
Always perform, rely and take into consideration your clinical evaluation before treatment decision.
In conclusion a low threshold of suspicion is crucial in order to correctly diagnosed and treat a SBI, reducing morbidity and mortality. As the authors state "even with negative imaging findings, serial clinical assessment is the main tool to decide wether the patient should undergo emergent exploratory laparotomy."
Do not forget what you were told in Medical School - clinical evaluation comes first. Do not forget signs and symptoms. Always read the imaging findings report after talking and touching the patient. You may have surprises...
Link to article:
Dr. Carlos Eduardo Costa Almeida
General Surgery