Just add ultrasound: ICU protocol additions aid diagnosis
Adding a head-to-toe ultrasound protocol to the physical examination performed on patients admitted to an intensive care unit can reveal many unsuspected clinical abnormalities, according to a study published in the October issue of Anesthesiology.

The ultrasound protocol used in the study resulted in a modified diagnosis for 26 percent of patients, according to study authors Emilpaolo Manno, MD, of Maria Vittoria Hospital, Torino, Italy, and colleagues.

“As part of rapid global assessment of the patient on admission, our ultrasound protocol holds potential for improving healthcare quality,” wrote the authors.

Physical examinations at admission to the ICU have been reported to be too often inaccurate, prompting a need for diagnostic imaging that has adequate sensitivity, availability and portability, according to the authors. To this end, they developed an ultrasound protocol, performed at bedside, which examines the optic nerve, thorax, heart, abdomen and venous system.

Manno and colleagues devised a prospective study of 125 consecutive patients admitted to an ICU to determine whether the protocol could detect occult anomalies, prompt changes in therapy, induce further testing or confirm diagnosis in situations where no major environment- or patient-related limitations are encountered.

Results showed that in addition to modifying diagnosis in more than one-quarter of patients, transthoracic ultrasound examinations led to changes in medical therapy in 18 percent of patients and prompted invasive procedures in 22 percent of patients. Findings also prompted further testing in 18 percent of patients.

Ultrasound was not effective in confirming or modifying diagnosis in 14 percent of cases, and missed diagnosis in 2 percent of patients. Environmental conditions hampered the exam moderately in 16 percent of patients and hampered it strongly in 3 percent of patients.

Breaking down the specific findings made possible by the addition of the protocol, the authors said that lung ultrasound was especially efficient in differentiating acute pulmonary edema from decompensated chronic obstructive pulmonary disease, asthma or pulmonary embolism in 20 percent of patients with shortness of breath or other signs of respiratory failure. Optic nerve sonography was able to detect intracranial pressure.

“Ultrasound examination revealed new findings of optic nerve sheath enlargement in six cases, in all of which computed tomography showed unknown intracranial hypertension, demonstrating the importance of this easy-to-perform ultrasound evaluation at admittance to a general ICU,” wrote Manno and colleagues.

The researchers plan to extend the ICU ultrasound protocol to include transcranial Doppler and positive end-expiratory pressure-induced lung recruitment.