Introduction:
Point-of-care ultrasound (POCUS) is a valuable tool in emergencies that provides a quick diagnosis. It is a test performed at the bedside to diagnose the abdomen. These POCUS machines are ultrasound machines that use sound waves, and these are affordable, movable, and can also be used by radiologists who are less trained.
What Is Point-Of-Care Ultrasound (POCUS)?
Point-of-care ultrasound is a type of ultrasound examination that makes decisions on the spot and is performed at the bedside by a physician as a part of a clinical examination. It can demonstrate blood flow and bowel movements. POCUS gives better diagnosis and, therefore, better patient care. The images produced are different due to the different densities. Black images demonstrate fluids, such as urine or blood. Gray images demonstrate soft tissues, such as the liver. White images without a shadow demonstrate fibrous tissues, and white images with a shadow demonstrate stones and bones.
What Are the Uses of Point-Of-Care Ultrasound in the Emergency Department?
The uses of POCUS in the Emergency Department include:
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Cardiac Evaluation: POCUS helps in assessing the cardiac anatomy, such as its chambers and valves, along with its function, which is useful in conditions such as myocardial infarction (reduced or blocked blood supply to the heart), heart failure, or pericardial effusion (accumulation of fluid in the outer membrane of the heart). In the case of cardiac failure, it can show real-time cardiac activity and can help in identifying massive pulmonary embolism (a blood clot in the lung) or cardiac tamponade (fluid accumulation in the outer membrane of the heart causing compression and decreased function of the heart). Apart from these, it also helps in detecting defects in the aorta called aortic dissection (a tear in the wall of the aorta) or aneurysm (a bulge in the wall of the aorta).
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Lung Evaluation: POCUS helps in detecting pneumothorax (collection of air in the outer membrane of the lungs) by visualizing the movements of the outer membrane of the lungs, called lung sliding. It can help in evaluating pleural effusion, which occurs due to the accumulation of fluid in the outer membrane of the lungs, and pulmonary edema (collection of fluid inside the lungs). Apart from this, POCUS also helps in evaluating lung consolidation, which occurs due to an inflammatory material or a fluid. Therefore, this can help differentiate cardiac and non-cardiac situations causing breathing difficulty.
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Obstetrical Evaluation: POCUS gives real-time visualization of fetal structures, uterus, and ovaries. It helps in assessing fetal cardiac activity during an ongoing pregnancy and helps in determining fetal position, such as a breech presentation or a transverse lie position. Apart from these, it can evaluate the amniotic fluid and, therefore, can recognize conditions, such as polyhydramnios (increased amniotic fluid) or oligohydramnios (decreased amniotic fluid). It can identify placenta previa in which the placenta covers the cervix and also helps in examining ectopic pregnancy which occurs when the egg is attached outside the uterus.
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Trauma Evaluation: POCUS helps in FAST (focused assessment with sonography for trauma) exam in case of traumatic patients by visualizing any internal bleeding or presence of fluids. It can quickly asses pneumothorax which requires early intervention. It also helps in assessing cardiac function along with its abnormalities, such as pericardial effusion, cardiac tamponade, myocardial contusion (a bruise in the membrane of the heart), or traumatic cardiac injury, abdominal and pelvic injuries, and vascular injuries, such as the presence of active bleeding, hematoma (a pool of blood outside the blood vessel in the tissues), or a vessel occlusion (blockage). Apart from these, it can also evaluate joint dislocations, fractures, and soft tissue injuries.
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Abdominal Evaluation: POCUS can be used in the case of acute appendicitis (inflamed appendix). It can be focused at the point of tenderness, and underlying structures can be seen with the help of the graded compression technique. POCUS can help in detecting intraperitoneal fluid (liquid in the abdominal cavity), which can occur due to ascites (accumulation of fluid due to liver diseases), traumatic bleeding, bile leak, ruptured ectopic pregnancy, and urinary leak. It can help in diagnosing the cause of intestinal obstruction. It can also help in detecting free intraperitoneal air that occurs due to leakage of bowel gas through the bowel perforation, which needs emergency treatment. Apart from that, it also helps in detecting gallstones by moving the POCUS probe from the central abdomen to the right side, and after localization of the gallbladder. In case of confirming gallstones, the patient is asked to move, which causes the gallstones to move.
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Vascular Access Guidance: POCUS helps in visualizing blood vessels and guiding needle placement for fluid replacement or drug delivery and, therefore, can assist in the identification of veins for IV (intravenous) cannulation, central venous catheter (CVC) insertion, intraosseous access (placement of the needle into the bone), and arterial cannulation. Apart from these, it can be helpful in difficult cases, such as obese patients or scarring for vascular access. It can help in avoiding complications, such as pneumothorax due to procedural complications, accidental puncture of adjacent structures, nerve injury, or hematoma.
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Procedural Guidance: POCUS helps in visualizing blood vessels and, therefore, can help in the identification of veins for IV cannulations, CVC insertions, intraosseous access, and arterial cannulation. It helps in the guidance of paracentesis (removal of fluid from the abdominal cavity) and thoracentesis (removal of fluid from the outer membrane of the lungs). Apart from these, it identifies safe puncture sites, helps in a procedure for the removal of CSF (cerebrospinal fluid) from the spine called lumbar punctures, visualizes the target nerve, draining fluids and abscesses, and also helps in visualizing the fracture alignment.
What Are the Benefits of POCUS Ultrasound in the Emergency Department?
Several benefits of POCUS ultrasound in the emergency department are as follows:
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It provides real-time imaging at the patient's bedside without any need for transport.
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In emergencies, POCUS helps in the rapid diagnosis of several medical conditions, such as abdominal trauma.
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It helps doctors in the direct visualization of anatomical structures.
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It also assists in guiding various procedures, such as joint aspiration.
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It reduces radiation exposure.
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It also helps in providing accurate assessments.
Conclusion:
POCUS is an important diagnostic tool that should be used by all primary healthcare sectors. Therefore, it can be used in cardiac, lung, obstetric, trauma, and abdominal evaluations. It also provides real-time visualization in case of needle placements for fluid replacement or delivering drugs, reduces procedural complications such as pneumothorax, hematoma, or injury to other structures, and therefore enhances patient safety. However, this requires appropriate training by the health sector staff.
