by Maryam Al Ali, MBBS; Abeeha Gardezi, MBBsch; Michael Jalal, MBBS; Shihab Al Sheikh, MB.ChB. CABS. MRCS. PgCert medical ultrasound.

Emergency Department, Rashid Hospital trauma center, Dubai Health Authority,Dubai, United Arab Emirates.

Download article PDF – POCUS Journal 2018; 3(1):15-17.

Introduction

Point of care ultrasound (POCUS) plays an important role in the Emergency Department or in any Critical Care Unit. In our case, we present how a POCUS mnemonic guided us in diagnosing two fatal conditions in a single case.

Case presentation

An 82-year-old male patient came to our emergency with a syncopal attack; triage vital signs were BP 112/67 mmHg, HR 167 beats per minute (irregularly irregular), RR 18/min, SPO2 97%, temperature 36.3. The patient was shifted to a resuscitation room. ECG showed Fast AF (online Figure S1). As the onset of AF was uncertain, a plan to start rate control therapy was initiated. Later, the patient was asymptomatic except for mild abdominal pain. The patient’s laboratory results came back with D-dimer 3.89 mg/L (normal level <0.5 mg/L), serum Lactate 7.3 mmol/L (0.5 – 2.2 mmol/L), troponin T 0.21 ng/ml (Between (0.1-2.0) ng/mL. High risk. Myocardial damage has been detected), cardiac Pro-BNP 8290 pg/ml (< 125). These alarming results were pointing towards a critical underlying pathology, with the first onset of AF plus High D-dimer, this could be pulmonary embolism. However, the patient denied having any breathing difficulty or chest pain, and had no clinical signs of DVT. The patient maintained oxygen saturation in room air at > 95%. This could also be mesenteric ischemia from acute embolic event; high lactate plus AF plus abdominal pain (which is mild abdominal pain, like his chronic abdominal pain from constipation).

Figure S1. Atrial fibrillation with rapid ventricular response.

We utilized the ACUTE mnemonic [1] to help us in the evaluation of patients presenting with an acute abdomen (Table 1). Hence, we scanned by using curvilinear probe looking for the Abdominal Aorta, Inferior vena cava, perforated viscus, free fluid in the abdomen, and ectopic pregnancy using the ACUTE mnemonic. The only positive finding in our patient was free fluid in right upper quadrant and pelvic area with dilated small bowel loop 3 cm thickened bowel loops 3 mm wall thickness (Figure 1). Therefore, the next plan of action was to perform a CT abdomen with contrast to evaluate for mesenteric ischemia.

Figure 1. Dilated small bowel loop 3 cm, thickened bowel loops 3 mm wall thickness with free fluid. * free fluid.

Table 1. ACUTE ABDOMEN mnemonic (Part A) for critical causes of acute abdomen.

Meanwhile, the patient became hypotensive with a blood pressure of 75/45mmHg, sinus tachycardia (spontaneously converted) and hypoxia. Resuscitation was initiated in our patient while we went back to POCUS to look for causes of hypotension by using the LOW BP mnemonic [2] (Table 2). A curvilinear probe was used for this scan for lung, cardiac, IVC, AA, and free fluid; and a linear probe was used for the DVT scan. The scan was negative except for free fluid in the abdomen (previous finding) and positive DVT in the right femoral (Figure 2). We then planned to include a pulmonary angiogram to rule out pulmonary embolism.

Figure 2. Right femoral vein incompressible, with absent Doppler flow in femoral vein confirmed DVT.

Table 2. LOW BP mnemonic for undifferentiated shock evaluation.

The CT scan showed left side pulmonary embolism at the level of the bifurcation of the left main pulmonary artery extending into the lower lobe segmental branches (Figure 3), perforated viscus (Figure 4), and prostate mass (Figure 5). The patient was referred to surgical, medical, urology, and the cardiology teams. The patient was shifted to the operating room for exploratory laparotomy with intra-operative findings of: perforated 2nd part of the duodenum. The patient was admitted in surgical ICU and his condition improved gradually; enoxaparin was started for the patient. After 15 days, the patient was discharged from the hospital.

Figure 3. CT pulmonary angiogram showed left side pulmonary embolism.

Figure 4. CT abdomen with IV contrast showed pneumoperitoneum, free fluid suggestive of perforated viscus.

Figure 5. CT abdomen with IV contrast showed prostate mass.

Table 3. ACUTE ABDOMEN mnemonic (Part B) for other surgical causes of acute abdomen.

Discussion

The use of POCUS is becoming widely established as a standard of care within Emergency and Intensive Care Departments. It is a safe, non-invasive tool, used as an extension of our clinical examinations; which can help answer focused questions and rule in or rule out life-threatening diagnoses rapidly.  LOW BP and ACUTE ABDOMEN both are new mnemonics, specially designed to address critical emergency approach of ABC (Airway, Breathing then Circulation). In the LOW BP mnemonic (Figure 5), it starts with causes of shock attributed to the ‘Breathing’ part of ABC, with letter L symbolizing Lung consisting of Pneumothorax and Pulmonary Edema. This is followed by the ‘Circulatory’ causes of shock composed of Cardiac output, IVC, Free fluid, AAA, pregnancy, DVT and PE. On the other hand, ACUTE ABDOMEN (Table 3) begins with the most critical cause: Abdominal Aortic Aneurysm. Other surgical causes of acute abdomen are listed in “ABDOMEN” part of the mnemonic (Table 3): Appendicitis, biliary tract disease, distended bowel loop, obstructive uropathy, Men: testicular torsion, and Women: ovarian torsion. Moreover, our mnemonics exhibit certain characteristics that make them easy to remember, such as they follow an anatomical approach and each mnemonic title represents the problem it is designed to address.

Conclusion

POCUS played a prominent role in the management and decision making process for this patient and a lot of other patients. Having an algorithmic approach with the ACUTE ABDOMEN, and LOW BP mnemonics will help Emergency Physicians or any Critical Care Physician rule out serious conditions that can be easily missed.

References:

1. Al Ali, M and Alrajaby S. Abdominal pain in ED – Using a novel sonographic approach. European Journal of Emergency Medicine. 2017; 24():e1-e15.
2. Sajid R, Hussein L, Saif M, Annajjar F. Low-BP; a simple approach to beside ultrasound use in undifferentiated shock. European Journal of Emergency Medicine. 2017; 24():e1-e15.
3. Coppolino FF, Gatta G, Di Grezia G, et al.: Gastrointestinal perforation: ultrasonographic diagnosis. Critical Ultrasound Journal 2013 5(Suppl 1):S4. DOI:10.1186/2036-7902-5-S1-S4
4. Goudie A. Detection of intraperitoneal free gas by ultrasound. Australasian Journal of Ultrasound in Medicine. 2013; 16(2):56-61.