Pulmonary transit of sonicated albumin microbubbles during controlled mechanical ventilation: A transthoracic echocardiographic study

Federico Bilotta, Laura Fiorani, Eugenio Lendaro, Sergio Picardo, Italia La Rosa, Giovanni Rosa, Francesco Fedele

Research output: Contribution to journalArticlepeer-review


Air-filled human serum albumin microspheres are ultrasonic contrast tracers that pass through the right ventricle, traverse the lungs, and effectively opacify the left heart chambers in spontaneously breathing patients. In this clinical study, we assessed whether they also do so in anesthetized patients during and after mechanical ventilation. In 20 anesthetized patients undergoing intermittent positive pressure ventilation (IPPV) for elective peripheral neurosurgical procedures, a sonicated ultrasound contrast drug (0.06 mL/kg) was injected IV before inducing anesthesia in spontaneously breathing patients (baseline), during IPPV, and 5 and 30 min after tracheal extubation. Transthoracic echocardiograms were obtained in the four-chamber apical view and were recorded for off-line analysis. Time to contrast appearance in the right ventricle and pulmonary transit time were measured in cardiac cycles. The peak intensity of right and left ventricular chamber opacification were scored on a scale ranging from 1 (no contrast or traces only) to 5 (attenuation). After each injection, the time for contrast appearance in the right ventricle was similar in all patients. Pulmonary transit time increased significantly during IPPV and was normal 5 min and 30 min after extubation. Right ventricular chamber opacification achieved high-grade intensity and remained constant before, during, and after IPPV. Conversely, although the baseline contrast injection resulted in high-grade left ventricular chamber opacification, the intensity decreased significantly during IPPV, remained low 5 min after extubation, and was normalized 30 min after extubation. Implications: During intermittent positive pressure ventilation, IV sonicated albumin microbubbles pass through the lungs poorly and inefficiently opacify the left ventricle compared with the effects observed during spontaneous ventilation.

Original languageEnglish
Pages (from-to)273-277
Number of pages5
JournalAnesthesia and Analgesia
Issue number2
Publication statusPublished - 1999

ASJC Scopus subject areas

  • Anesthesiology and Pain Medicine


Dive into the research topics of 'Pulmonary transit of sonicated albumin microbubbles during controlled mechanical ventilation: A transthoracic echocardiographic study'. Together they form a unique fingerprint.

Cite this