Perforated Viscus

by Ozlem Dikme – Turkey

Case Presentation

A previously healthy 42-year-old male presented to the Emergency Department (ED) with a 3-day history of worsening abdominal pain. He felt nauseated and vomited twice. His pain started around the umbilicus, moved to the left side of his abdomen and then become generalized. It peaked the last few hours, and the painkillers did not work. His social history revealed that he was non-drinker, non-smoker and did not use any illicit drugs. The past and family histories were unremarkable. His blood pressure was 100/60 mmHg, pulse rate 120/min, the temperature 37.8°C (100°F), and respiration rate 24/min. Physical examination showed diffuse abdominal tenderness and voluntary guarding. Bowel sounds were not heard. Bedside ultrasonography (USG) exhibited increased echogenicity of the peritoneal stripe, with corresponding horizontal reverberation artifacts over the liver. Plain chest radiographs confirmed the presence of free abdominal air. Oral intake was stopped, intravenous (IV) catheter was inserted, fluid therapy was started, and cefoperazone sodium was administered intravenously. Blood type and cross, complete blood count and coagulation were ordered. He transferred to the operation theater with the diagnosis of the perforated viscus.

Can you identify free air on the X-ray?

Critical Bedside Actions and General Approach

All critically ill patients with acute severe abdominal pain is a candidate to have a viscus perforation. The first step is always patient evaluation with ABC approach and stabilization. These patients present to the ED with a severe abdominal pain and discomfort. Because of the pain severity, they may not let you touch their abdomen. They prefer to stand still because of any movement trigger pain. They look sick. Our first priority is to ensure there is no immediate life or organ-threatening situation. If so, immediate actions should be done at the bedside during the initial evaluation. Airway, breathing, and circulation evaluations are completed. However, quick, focused abdominal examination can be done before the full secondary evaluation. Opening two large bore IV lines, fluid therapy, stopping oral intake are some of the routine actions. Patients are attached to the cardiac monitor. Necessary blood samples are collected and sent. The pre-diagnosis of perforated viscus must be explained to the patient, and his approval should be obtained for further evaluation and treatment. The US can be used at the bedside as an adjunct to focused history and physical exam.

Differential Diagnoses

During the initial evaluation, emergency physicians try to understand possible differential diagnoses in a patient with severe abdominal pain. The below list is given in alphabetical order.

Abdominal Aortic Aneurysm
Acute Cholecystitis or Biliary Colic
Acute Gastritis or Peptic Ulcer Disease
Acute MI
Acute Pancreatitis
Aortic Dissection
Appendicitis
Diabetic Ketoacidosis
Diverticulitis
Gastrointestinal carcinoma
Inflammatory Bowel Disease (Crohn Disease, Ulcerative Colitis)
Mesenteric ischemia
Omental torsion
Rectus sheath hematoma
Tubo-ovarian pathologies (Ectopic pregnancy, Pelvic inflammatory disease, Abscess, Endometriosis, Ovarian cyst/torsion, Uterine leiomyomata)

History and Physical Examination Hints

Thorough medical history usually reveals predisposing factors or possible etiology of perforation. Predisposing chronic conditions include peptic ulcer disease, inflammatory bowel disease, malignancy. Acute conditions like acute appendicitis, acute diverticulitis, infections (e.g., typhoid fever), intestinal ischemia, necrotizing vasculitis and penetrating or blunt injuries may cause perforation. Additionally, caustic substance and foreign body (e.g., toothpicks) ingestions, endoscopic interventions and some medications are associated with perforation. Most common medications are aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) and steroids.

The patient typically presents with sudden and severe abdominal pain. Asking patients about the characteristics of pain helps to diagnose. Typical pain starts around a limited location, then expands to all abdomen in a short time. A history of frequent abdominal pain may suggest the patient has a predisposing condition. Free air under the diaphragm may cause referred pain to the either or both shoulders. Vomiting is present in 50% of patients. Shock, sepsis, gastrointestinal or intraabdominal bleeding may accompany perforation.

Ulcer perforation refers to when the ulcer erodes through the wall and leaks air and peptic contents into the peritoneal cavity. The anterior wall of the duodenum is the most common site. Approximately 2 to 10% of patients with peptic ulcer undergo perforation once in their lives.

Contamination of the sterile peritoneal cavity with the chemical and bacterial intestinal content causes inflammation, infection, and sepsis. Therefore, patients may become tachypneic, tachycardic and hypotensive in short time. Immunocompromised or critically ill patients with other comorbidities pose a greater risk for perforation. Obscure presentations in these patients may delay the diagnosis.

Fever and tachycardia are common. Typically, initial low-grade fever increases over time. Peritoneal findings are almost always present. Diffuse guarding and rebound tenderness are likely. “Boardlike” abdomen is a late sign. Bowel sounds are found decreased in the majority of the cases.

Emergency Diagnostic Tests and Interpretation

An essential step of the evaluation is imaging and laboratory tests. Erect chest or left lateral decubitus radiographs may reveal pneumoperitoneum. Bedside US may shorten the time to diagnosis and surgical consultation. If these methods do not confirm pneumoperitoneum, the physician should proceed with computerized tomography (CT) or laparotomy options by discussing with surgery. Laboratory tests are not specific to diagnose but may exclude the other differential diagnoses.

Bedside Tests

The US is a highly sensitive modality in scanning for peritoneal free air. Recently attention of this technique has been a rise, and it became a popular rapid diagnostic test in EDs. Characteristic US signs of pneumoperitoneum are the ring down artifact and enhancement of the peritoneal stripe over the liver often caused by fluid trapped between gas bubbles. When experienced hands use the US its sensitivity of pneumoperitoneum achieves an almost 93%.

The US video link

Laboratory Tests

Laboratory studies are generally not specific to diagnose. Use of these tests is valuable for the preparation before the surgery and information about the patient basal status. Type and cross, hemoglobin/hematocrit, platelet and coagulation studies are the minimum tests for this purpose. Additionally, blood gas analysis, lactic acid, liver and renal function tests, lipase/amylase and urinalysis can guide to diagnose and post-surgical care. WBC count usually elevated owing to peritonitis. Amylase may be elevated; liver function test results are variable.

Imaging Modalities

Plain radiography has a sensitivity demonstrating pneumoperitoneum ranging from 30 to 80%, thus making it is a questionable initial study when a perforated peptic ulcer is considered likely. Free air rises to its highest elevation in the body when the patients sit upright or in positions of left lateral decubitis for at least 10 minutes. Thus it results in increased sensitivity of the radiography. Perforation suggestive findings include subdiaphragmatic free air, visible falciform ligament and air-fluid level. Radiography can be used as an initial screening exam. Thus, a patient may more expediently go to surgery with positive plain radiography. It also has the advantage of being obtainable portably at the bedside with little interruption in patient monitoring or care. On the other hand, free air cannot be identified in 30% of patients approximately. Thus plain radiography is not sufficiently sensitive to rule out perforation.

Can you identify free air on the X-ray?

The CT is the most sensitive and specific imaging test in diagnosing a perforated viscus. CT scan has the additional findings of accompanying intra-abdominal abnormalities and etiological changes. It has numerous advantages, first of all, it can detect the small volume of pneumoperitoneum or retroperitoneal free air. Secondly, it can point out that the potential location of the perforation site and known of this may help the surgeon in operation and finally it can provide alternative diagnoses if no pneumoperitoneum is identified. Perforated viscus detection of oral and IV contrast CT scans has shown as 95 to 98% sensitivity in many protocols.

Can you identify free air on the CT?

Emergency Treatment Options

The initial management focuses on resuscitation, appropriate antibiotic selection, and immediate surgical consultation. Regardless of the cause, if signs of intestinal perforation with peritonitis are present, prompt emergent laparotomy is indicated. The critically ill patient with a suspected perforated viscus should be in the ED resuscitation area with two large IV line, oxygen, and close monitoring. Crystalloid fluids and antibiotics are medical treatment essentials. In the emergency setting, antibiotics should cover gram-negative, gram-positive and anaerobic pathogens. Two sample regimens are below. Fore more regimens, and please visit given links under the references and further reading.

A Sample Antibiotic Regimen In Perforated Viscus

Antibiotic Regimen	Pregnancy Category	Dosage
Ceftriaxone and	B	Adult: 1-2 gr IV (bid) Pediatric: 50-75 mg/kg/day IV (bid)
Metronidazole	B	Adult: Loading dose: 15 mg/kg IV (max: 4 grams), 7.5 mg/kg IV (bid or tid) Pediatric: 15-30 mg/kg/day IV (bid or tid) (Check dosage for neonatal of children <2 kg)

Meropenem	B	Adult: 1-2 gr (tid) Pediatric: 20 mg/kg – 1 gr (tid) (Check dosage for children <3 months)

Pediatric, Geriatric, and Pregnant Patient Considerations

In the pediatric population, two etiologies of perforation are prominent: Blunt trauma and intussusception. Vehicle-related trauma, bicycle handlebar injuries, and seatbelt syndrome are common causes of perforation secondary to blunt trauma in children. Intussusception refers to invagination or “telescoping” of a part of the small intestine into itself. Most cases are children younger than two years. It leads to venous and lymphatic congestion and subsequent intestinal edema. As a result, intestinal ischemia and perforation may occur.

Perforated viscus incidence increases with advancing age. History of peptic ulcer disease or diverticular disease is common in elderly. Medicine-related perforation is common in the geriatric population. NSAIDs increase the risk of colonic perforation in patients with diverticular disease. In an elderly with lower abdominal pain, the physician should suspect perforated diverticulitis or appendicitis.

Disposition Decisions

All patients require intensive care unit admission. The majority of patients with perforated viscus require laparotomy to explore the whole gastrointestinal system, remove spilled ingredients and repair the lesion. Selected self-closing lesions such as a duodenal perforation covered by omentum may be an exception. They may not need emergent laparotomy but close monitoring and intravenous large-spectrum antibiotics treatment. Alternative methods of source control such as the use of endoscopic clips for iatrogenic colon injury during colonoscopy are under investigation.

References and Further Reading

Langell JT, Mulvihill SJ. Gastrointestinal perforation and the acute abdomen. Med Clin North Am. 2008;92(3):599-625.
Mularski RA, Sippel JM, Osborne ML. Pneumoperitoneum: a review of nonsurgical causes. Crit Care Med. 2000;28(7):2638-2644.
Hess JM, Lowell MJ. Esophagus, Stomach, and Duodenum, Chapter 89. In: Marx JA, Hockberger RS, Walls RM, editors. Rosen’s Emergency Medicine Concepts and Clinical Practice, 8th edition. Philadelphia: Elsevier; 2014:1170-1185.
Budhram GR, Bengiamin RN. Abdominal Pain, Chapter 27. In: Marx JA, Hockberger RS, Walls RM, editors. Rosen’s Emergency Medicine Concepts and Clinical Practice, 8th edition. Philadelphia: Elsevier; 2014:223-231.
Gajic O, Urrutia LE, Sewani H, Schroeder DR, Cullinane DC, Peters SG. Acute abdomen in the medical intensive care unit. Crit Care Med. 2002;30(6):1187-1190.
Blaivas M, Kirkpatrick AW, Rodriguez-Galvez M, Ball CG. Sonographic depiction of intraperitoneal free air. J Trauma. 2009;67(3):675.
Kuzmich S, Harvey CJ, Fascia DTM, et al. Perforated Pyloroduodenal Peptic Ulcer and Sonography. AJR Am J Roentgenol. 2012;199(5): W587–W594.
Jones R. Recognition of pneumoperitoneum using bedside ultrasound in critically ill patients presenting with acute abdominal pain. Am J Emerg Med. 2007;25(7):838-841.
Solomkin, J. S., Mazuski, J. E., Baron, E. J., Sawyer, R. G., Nathens, A. B., DiPiro, J. T., … & Chow, A. W. (2003). Guidelines for the selection of anti-infective agents for complicated intra-abdominal infections. Clinical Infectious Diseases, 37(8), 997-1005.
Roline CE, Reardon RF. Disorders of the small intestine, Chapter 92. In: Marx JA, Hockberger RS, Walls RM, editors. Rosen’s Emergency Medicine Concepts and Clinical Practice, 8th edition. Philadelphia: Elsevier; 2014:1216-1224.