The use of a bronchial blocker compared with a double-lumen tube for single-lung ventilation during minimally invasive direct coronary artery bypass surgery.

OBJECTIVE: To investigate whether a bronchial blocker (BB) placed through a routinely used single-lumen tube (SLT) to achieve 1-lung ventilation is appropriate in patients undergoing a minimally invasive direct coronary artery bypass (MIDCAB) operation. DESIGN: Clinical trial. SETTING: University hospital. PARTICIPANTS: Patients scheduled for elective MIDCAB operation (n = 159). INTERVENTIONS: Group A was treated with a left-sided double-lumen tube (DLT) and served as the control group. Group B was intubated with a routinely used SLT in combination with a BB. MEASUREMENTS AND MAIN RESULTS: The following data were collected: (1) time required for placement of each tube, (2) ventilation pressures, (3) lung compliance, (4) dislocations of the DLT or BB, (5) effectiveness of lung collapse, and (6) PaO(2) and fraction of inspired oxygen. In 4 patients (4%) of group B, the BB could not be placed within an acceptable time so that 155 patients (50 patients in group A, 105 patients in group B) were statistically analyzed. Statistically significant differences during 1-lung ventilation were found for peak and mean inspiratory pressure (p < 0.001 and p < 0.05), dynamic and static lung compliance (p < 0.05), and dynamic lung compliance change (p < 0.01). No statistical significance was found for intubation time (p > 0.05) and PaO(2) and fraction of inspired oxygen (p > 0.05). Lung collapse was insufficient in 1 patient of group A (2%) and in 2 patients of group B (2%). CONCLUSION: To achieve 1-lung ventilation during a MIDCAB procedure, the use of a BB combined with an SLT is an appropriate technique as an alternative to the commonly used DLT.

[Safety and efficacy of LK565--a new polymer ultrasound contrast medium]. / Untersuchungen zur Sicherheit und Effizienz von LK565--einem neuen Polymer-Ultraschallkontrastmittel.

We tested a newly developed ultrasound contrast agent (LK565) from poly-aspartic acid (PAA; particle size 3 microns; particle content: air) in 15 healthy male probands (20-38 years) in doses of 10, 30 and 100 mg intravenously. One day and immediately before the study a routine laboratory test, an ECG and an EEG were performed. The EEG was continued through the complete time period that the ultrasound contrast lasted, i.e., up to one hour after the injection. All probands were followed clinically for 24 hours when the routine laboratory and the ECG were repeated. All subjects tolerated the contrast agent well. There were no changes in either the EEG or in the ECGs performed throughout the study. There were no significant laboratory changes except for a small and transient increase in the neutrophil count in five probands receiving the highest dose. All injections with 10 mg led to a significant improvement in the color Doppler signal. All injections with 30 and 100 mg led to a very strong echo contrast lasting for 5 to 12 minutes in the harmonic B-mode. Using the latter, fragments of intramyocardial coronaries could be visualized. The tested ultrasound polymer contrast agent was safe, well tolerated and efficient in this acute study.