Point-of-Care Ultrasound Case Pearl in
Neurocritical Care
By Gabriel Prada, MD1; Jose L. Diaz-Gomez, MD1,2; and Aarti Sarwal, MD3
Affiliations: 1Department of Critical Care Medicine, Mayo Clinic,
Jacksonville, Florida; 2Department of Neurologic Surgery, Mayo
Clinic, Jacksonville, Florida; 2Departments of Neurology and
Critical Care, Wake Forest School of Medicine, Winston Salem,
North Carolina.
Point-of-care ultrasound (POCUS) is ultrasonography performed
by the provider in real time at the bedside to help clinical decision
making. POCUS is increasingly being implemented as a powerful
tool for screening, diagnosis, monitoring of critically ill patients
as well as procedural guidance. POCUS complements the physical
examination, improves immediate bedside therapeutic decision
making, and optimizes the choice and the yield of further
diagnostic testing.
Focused Assessment with Sonography for Trauma (FAST)
examination is an ultrasound-driven evaluation of the torso
indicated in patients after traumatic injury. The FAST exam
maximizes the probability for early detection of pericardial,
pleural and peritoneal free fluid (blood, urine or bile), which
appears as a hypoechoic (i.e., black or dark gray) collection.
The extended FAST exam (e-FAST) incorporates anterior-chest
ultrasonography for the identification of pneumothorax. A
recent study demonstrated that e-FAST, compared to computed
tomography, demonstrated specificities of 100 percent for
pneumothorax and 98.4 percent for peritoneal free fluid, but
sensitivities of 100 percent, 75 percent and 42.9 percent for pleural
effusion, pneumothorax and peritoneal free fluid, respectively.
Knowledge of practice guidelines for the performance of the FAST
examination may be of great educational value to a neurointensivist
even in non-traumatic cases. Using a low-frequency (2.5 to 5 MHz)
curvilinear or phased-array transducer, the standard FAST exam
consists of the following evaluations of the heart for pericardial
fluid: right flank (hepato-renal view/Morison’s pouch), left flank
(peri-splenic view) and pelvic (retro-vesical view) for peritoneal
fluid and lateral and anterior thoracic views for hemothorax and
pneumothorax, respectively. FAST may not be useful in patients
with obesity, subcutaneous emphysema and lesions that produce
smaller than 200 ml of free fluid (>200 ml) but in cases of acute
traumatic shock can help identify free fluid and triage need for
exploratory laparotomy.
We describe the use of FAST exam in a 68-year-old man with
diagnosis of locked-in syndrome who underwent tracheostomy
and percutaneous endoscopic gastrostomy. Upon return to
the neurointensive care unit, the patient developed shock
unresponsive to fluid resuscitation, consequently requiring
vasopressor support. There was no drop in hemoglobin noted.
With patients cardiac history presumed, cardiogenic shock was
suspected. Increasing vasopressor requirements with worsening
shock necessitated further assessment. The neurointensivist team
performed POCUS of heart with parasternal long and short
axis views showing normal gross biventricular function, mild
pericardial effusion but no signs of tamponade physiology (Figure:
1 and 2) ruling out cardiogenic shock. An e-FAST exam revealed
peritoneal free fluid in the hepato-renal and peri-splenic views
(Figures 2 and 3), and absent hemothorax and pneumothorax.
POCUS exam took approximately five minutes to complete.
Emergency general surgery was contacted who took the patient
for emergency laparotomy and found extensive mesenteric
hematomas from a bleeding source related to peg tube placement.
Successful control of source of bleeding was done with good
clinical course and the patient was discharged to a long-term care
facility within next 48 hours for further supportive care.
This case highlights the practicability and diagnostic utility of
POCUS for the neurointensivist. Without POCUS, this patient’s
cause of shock could not been narrowed down in a time
efficient manner. Detection of the cause in this case preceded
clinical signs of acute abdomen. Conventional diagnostic
testing (echocardiography followed by computed tomography)
would have not been able to narrow down the etiology in such
a short time and could have been associated with high risk of
circulatory collapse during transport. We encourage all providers
in neurocritical care to learn basic critical care point of care
ultrasound as a useful tool in improving patient care.
For further POCUS learning opportunities, please check out the
2018 Annual Meeting Workshops and sign up for the Critical
Care Ultrasound workshop. If you are looking for volunteer
opportunities at the workshop, please contact
info@neurocriticalcare.org.
Gabriel Prada, MD Jose L. Diaz-
Gomez, MD
Aarti Sarwal, MD
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