What is Ultrasound?

Brandon Geer, APRN

Ultrasound by definition is a collection of sound waves with frequencies above the limits of human hearing. The concept came from bats that navigated and hunted based on inaudible sound. Ultrasound was first used in World War I. A military scientist named Paul Langevin created a device to detect submarines. This has since been further studied and developed into a tool used widely in the medical community. Ultrasound transducers use sound waves to determine distances away from the transducers. Sound waves react to different tissue types and are converted to images.

New Uses for Ultrasound

Ultrasound is a relatively new diagnostic tool in medicine. It was, first used in the 1950s in neurology, ophthalmology, and obstetrics. Ultrasound imaging is widely used in medicine – both in and out of the hospital setting. Ultrasound can image virtually any part of the human body. It can also be used for procedures. Common procedures include intravenous access, joint injections, and abscess drainage (Geer, 2021). Ultrasound was first thought to be a complex, obscure, and high-level diagnostic tool. More recently, it has also been easily adopted by non-physician specialties. Today, it used regularly by advanced practice providers (APPs), nurses, and paramedics. This raises the question of where ultrasound can and should be used.

Original technology included transducers hooked up to a large computer. This was rather difficult to move around the hospital. As with most technology, this technology has become increasingly smaller to the point of becoming handheld. This has greatly increased the accessibility and utility of ultrasound, and has also led to the concept of “point of care ultrasound” (POCUS). This new technique also allows any trained medical professional to complete a variety of different tasks in a diverse collection of environments.

Picture the following scenarios:

No IV Access

A 64-year-old male presents to a small rural emergency department for abdominal pain, nausea, vomiting, and dehydration. He has a history of IV drug use which has rendered most of his veins useless. The emergency department staffs 3 RNs who are fantastic at IVs, but are unable to place an IV despite several attempts. There is no IV service at this hospital, and ultrasound is only available during the day, however the patient is sick and needs IV access.

The emergency provider quickly heads to their radiology department to obtain their device, pulls it into the patient’s room, and is able to perform a vascular assessment to place a peripheral IV in the patient’s brachial vein under ultrasound guidance. As a result of ultrasound, the patient is treated and sent home without any issues.

Cellulitis

A 47-year-old male presents to Urgent Care for a “pimple” that he first noticed about 1 week ago in his right groin that he “popped”, and tried to treat with warm compresses. The site has progressively swollen over the past week, and is now erythematous and painful to the touch. The nurse practitioner assesses the site, and believes there may be some fluctuance to the site, but is unsure if he should perform an I&D for a suspected abscess.

The nurse practitioner pulls his handheld ultrasound device out of his lab coat, and evaluates the site, which does not identify any collections of fluids, but does identify “cobble stoning” of the skin which shows cellulitis. The provider also notes that the site sits just above the femoral artery. An incision and drainage is unnecessary because there is no fluid collection.

Dialysis Fistula Patency

A 73-year-old female presents to the dialysis center having missed the last 2-3 treatments, and is short of breath due to the extra fluid she has on board. She states she has been afraid to come to dialysis because the nurse “always has trouble” with accessing her fistula. The patient couldn’t take the pain or poking, and so she skipped the last couple treatments as she felt the pain was not worth the treatment.

In anticipation of this, the dialysis unit obtained a new ultrasound device used specifically for evaluation of fistulas, both to evaluate patency, and to assist with cannulation.

Abdominal Trauma

A 23-year-old woman is involved in a motor vehicle collision. The accident was in a rural area about 15 minutes away from a small community hospital, and also about 30 minutes away from a city trauma hospital. The patient complains primarily of leg and elbow pain, as well as mild dizziness. Her vital signs reveal a blood pressure of 104/73 and a heart rate of 108. She wants to go to the community hospital as she doesn’t feel like she’s very sick.

The ambulance has an ultrasound device on board. The paramedic performs a FAST exam. This reveals fluid in “Morrison’s pouch”, and so the paramedic makes the determination to bring the patient to the trauma hospital instead, as they need a lot more services than the community hospital has to offer.

Many More Uses!

These are just a few scenarios that show the utility of ultrasound devices in practice. They have a wide range of utility, from obstetric evaluations to evaluation of vascular fluid levels (through imaging of the inferior vena cava). Ultrasound can also be used to obtain vascular access. It can also help with guiding sensitive procedures. It has also been used in a variety of settings, including outpatient facilities, hospitals, and rural areas.

We are finding more uses for ultrasound as its use grows. Underserved areas such as rural Vietnam have embraced this modality to triage or rapidly identify life threatening ailments. These include cardiac abnormalities and trauma. In fact, many of these underserved areas have helped prove that many healthcare providers can become proficient in the use of ultrasound with minimal training.

Ultrasound Devices and Portability

Ultrasound devices used to be large, bulky, and confined to a designated ultrasound room. This simply is not the case any longer! These devices have progressively decreased in size to the point where they can fit in a pocket. Likewise, this makes ultrasound invaluable in providing quick assessments in a variety of settings. The creation of pocket ultrasound devices, and general portable ultrasound devices has also led to a race amongst different ultrasound companies to provide the best possible portable ultrasound device.

If you work in the healthcare system, it is likely that you’ve seen a Philips or Sonosite device, usually on wheels with a large screen and multiple transducer options. These are fantastic options to offer high quality imaging on a large screen, and can offer multiple disciplines fast access to a high end ultrasound picture. These machines are also large and bulky and usually confined to a unit or building.

Portability

Portable ultrasounds offer greater availability, and offer any provider to bring an ultrasound with them wherever they may be. You may have heard of the Butterfly Ultrasound, the GE VScan, or the EagleView. These offer greater versatility, and depending on the device, often don’t compromise much on quality. Personally, I have found great utility with the Butterfly and Eagleview. These devices have also allowed me to bring point-of-care ultrasound availability to such settings as the Emergency Department, Urgent Care, Primary Care, and even rural healthcare settings like community health clinics in rural Peru.

Ultrasound devices are being used everywhere. Providers need minimal training to use it. Several studies have shown that as little as four hours of training is effective. This can provide significant access to point of care ultrasound, and can provide vast improvement and augmentation of the healthcare industry overall. If more people utilize ultrasound, and practice with ultrasound devices, we can provide significantly improved patient care, and can provide a significant service to the patient populations we see.

References

Geer, B. (2021). Using point-of-care ultrasound in nursing. Nursing2021, 51(6), 50-52. doi:
10.1097/01.NURSE.0000743052.88928.dc

Kirkpatrick JN, Nguyen HTT, Doan LD, et al. Focused cardiac ultrasound by nurses in rural
Vietnam. J Am Soc Echocardiogr. 2018;31(10):1109–1115. DOI: 10.1016/J.ECHO.2018.05.013

Mayo Clinic Staff. (2020). Ultrasound. MayoClinic. Retrieved from:
https://www.mayoclinic.org/tests-procedures/ultrasound/about/pac-20395177

O’Rourke, K., Kibbee, N., Stubbs, A. (2015). Ultrasound for the evaluation of skin and soft tissue infections. Missouri Medicine, 112(3), 202-205. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6170135/