Читать книгу Point-of-Care Ultrasound Techniques for the Small Animal Practitioner - Группа авторов - Страница 96

Not all ultrasound machines were designed for the battlefield with parts that can sustain a six‐foot drop. Most were designed for the relative quiet and safety of a hospital. Ultrasound machines and their components can be easily damaged or broken by rough handling and improper use, and replacement can be costly, especially if you drop an ultrasound probe and damage its crystals. Dropping the probe is the most common cause of probe damage and machine misuse.

The second most common form of misuse involves probe head damage (Figure 4.13). There are two major forms of probe head abuse: needle damage and chemical damage. With the use of POCUS as standard of care for many invasive procedures on the human side, now fast spilling over into veterinary medicine, needle damage, in other words stabbing or catching the rubber probe head with the point of the needle, quickly leads to severe probe head damage. In the haste of the moment, the attending sonographer will often grab a bottle of isopropyl alcohol, wet down the fur with only the alcohol, and apply the probe, leading over time to chemical damage. Many ultrasound manufacturers list alcohol as an inappropriate liquid to place in direct contact with the probe head because alcohol, over time through desiccation, can cause probe head damage.

Figure 4.13. Probe head damage. The damage to the surface of this probe was attributed to a combination of repeated or prolonged contact with isopropyl alcohol and needle trauma. The contact layer is clearly lost over a portion of this probe, negating its ability to serve as an electrical insulator between the probe and patient. It is possible for potentially serious electric shock to occur through the damaged area.

Source: Courtesy of Robert M. Fulton, DVM, Richmond, VA.

Pearl: Always use acoustic coupling gel on the probe head and be familiar with the guidelines provided by the ultrasound machine's manufacturer.

Importantly, it should be noted that the rubber probe head accomplishes two things. First, it acts as a coupling medium to transmit the sound wave out of the probe. Second, it is part of an electrical insulator serving as an electrical ground between the patient and the electricity being sent from the ultrasound machine to the transducer's crystals. There are currently no reports of electrocution via a damaged ultrasound probe but theoretically it's possible.

Pearl: Avoid probe head damage by using an acoustic coupling medium on the probe head as a barrier to alcohol, and avoid stabbing the probe head with needles during ultrasound‐guided procedures.