Ultrasound imaging has been around for decades, often used to help diagnose infections and pain within the body. But medical advancements in the past few years have extended its usage all the way to the operating room, where anesthesiologists are now using it to make orthopedic surgery safer.
Ultrasound-Guided Regional Anesthesiology
Over the past 10 years, ultrasound guided regional anesthesiology (UGRA) has become routine practice for anesthesiologists at Hospital for Special Surgery (HSS). Prior to UGRA, nerve blocks were guided blindly by anatomical landmarks or by nerve stimulation, but UGRA has been shown to improve patient outcomes including improving pain scores and decreasing complications after orthopedic surgery.
Using ultrasound to guide local anesthetic to a specific part of the body helps the anesthesiologist avoid vital structures, such as blood vessels. Ultrasound guidance also enables anesthesiologists to selectively block the sensory branch of a nerve, without affecting the motor branch, retaining muscle function and resulting in less pain and an earlier re-entry into everyday function after knee or hip surgery.
Ultrasound guidance improves the success of peripheral nerve blocks which have been linked to lower incidences of postoperative nausea and vomiting, less reliance on prescription pain medications, and lower hospital-acquired infection rates. Future research on ultrasound involves studying the application of 3D and 4D ultrasound technology to improve delivery of localized anesthetics for orthopedic patients.
Point-of-Care Ultrasound (PoCUS)
Anesthesiologists are using point-of-care ultrasound (PoCUS) in addition to a stethoscope during physical exams. This is because PoCUS imaging allows clinicians to visualize the targeted structure, such as the heart, lungs or blood vessels, improving the possibility of diagnosing potentially adverse conditions, whereas a stethoscope primarily offers an audio analysis.
PoCUS, while not exposing the patient to radiation, may facilitate early diagnosis and minimize the need for delay in management of patients with major health issues. These ultrasound techniques, in conjunction with other imaging modalities, such as X-ray, CT scan and MRI, may allow for more rapid (and in some instances, more accurate) diagnosis of potentially life-threatening conditions.
The use of PoCUS can help anesthesiologists more effectively determine which patients can be safely taken directly to the operating room or patients that need to be delayed for more extensive testing before surgery. Anesthesiologists also use PoCUS to better assess why a patient may be unstable after surgery and more rapidly diagnose and manage those patients. It provides helpful information about of the baseline function of the heart and lungs before urgent or emergent surgery. This type of insight improves the anesthesiologists’ ability to manage patients in the critical time surrounding surgery.
As technology evolves, the basic tools clinicians use to assess patients change as well. Like UGRA, PoCUS has the potential to improve patient management for all medical and surgical subspecialties. In routine and urgent settings, using ultrasound imaging to help in the timely assessment and diagnosis of medical conditions is going to become more commonplace among general practitioners, critical care physicians, orthopedic surgeons, and anesthesiologists.
For example, a recent study at Hospital for Special Surgery published in a major anesthesia journal demonstrated how PoCUS can be used at the bedside to identify and diagnose patients at increased risk of pain after hip arthroscopy surgery due to fluid tracking from the hip joint into the abdomen. This study is just one example of the many potential uses for PoCUS.
It is a natural evolution of ultrasound technology to consider its uses outside its more traditional indications. Just a decade ago, using ultrasound to guide peripheral nerve blocks was considered novel; now regional anesthesiologists routinely use ultrasound to improve localized delivery of anesthetics. Now anesthesiologists are tapping into the role of ultrasound in the entire surgical period – before, during and after – in order to make orthopedic surgery even safer. Adapting and innovating with ultrasound imaging technology will undoubtedly impact and improve anesthesiology for orthopedics for decades to come.
Dr. Stephen Haskins, MD, is an assistant attending anesthesiologist at Hospital for Special Surgery. He lectures on and teaches point-of-care ultrasound courses across North America.