Determination of the True Inclination Angle of the Main Bronchi Relative to the Median Sagittal Plane for Placement of a Left-Sided Double-Lumen Tube.

OBJECTIVES: This study aimed to determine the true inclination angle of the main bronchi relative to the median sagittal plane, using CT imaging to help increase accuracy of double-lumen tube (DLT) placement. DESIGN: In this retrospective study, 2 investigators independently measured normal chest CT scans from 50 male and 50 female patients. To determine the true AP axis, a mid-sagittal plane reference line (MSPRL) was drawn, intersecting the midsternum and the vertebral spinous process at the level of mid-carina. Lines were drawn through the center of each main bronchus to determine the inclination angle with regard to the MSPRL. SETTING: Research was conducted at a single institution, the Los Angeles County and University of Southern California Medical Center. PARTICIPANTS: Normal chest CT images from 50 women and 50 men. MAIN RESULTS: The mean true inclination angle between the main bronchi and trachea in the mid-sagittal plane was 108.4° on the left compared with 96.2° on the right (p<0.0001). INTERVENTIONS: No specific interventions were done because this was a retrospective study and CT scan analysis. CONCLUSION: The data suggested that the trachea does not merely branch in the horizontal plane but branches posteriorly as well, with a true mean anatomic angle between the left main bronchus and trachea of 108.4°. This finding concurred with the authors' suggestion that the DLT be rotated to 110° counterclockwise instead of the routine practice of 90°. The authors suggest clinicians rotate the DLT an additional 20° counterclockwise and direct the top of the DLT to the 11 o'clock position.

The use of regional cerebral oximetry monitoring during controlled hypotension: a case series.

Regional cerebral oximetry monitoring was used to guide nitroglycerin infusion and IV fluid administration during controlled hypotension in order to optimize each individual patient's mean arterial pressure in a series of 20 consecutive patients who underwent major open urological or abdominal surgery. Although controlled hypotension offers a definite benefit in patients undergoing complex surgery where blood loss will be elevated or would severely compromise the surgical field, it is not without risk as low arterial pressure may compromise tissue perfusion and promote ischemia. In this case series, despite an average mean arterial pressure decrease of 19.5 % (p < 0.001), cerebral oximetry values increased by an average of 22.7 % (p < 0.001) after the nitroglycerin infusion had been initiated (220 mcg/min average). Patients received an average of 3.15L crystalloid and 437 ml albumin in fluid resuscitation.

Rates of symptom reoccurrence after endovascular therapy in subclavian artery stenosis and prevalence of subclavian artery stenosis prior to coronary artery bypass grafting.

Percutaneous transluminal angioplasty (PTA) and stenting is commonly used to treat subclavian artery stenosis (SAS). In this study, the outcomes of 43 consecutive cases, performed at one institution from October 1997 to October 2005, were analyzed. Mean stenosis was 84.41% pre-intervention and 6.83% post-intervention. Five of the procedures were angioplasty alone; 38 were angioplasty with stenting. Technical success was achieved in 42 out of 43 patients. The 30-day mortality rate was 0%. At one-month post intervention, all patients were symptom free. Ten patients redeveloped symptoms by one year. Demographic data, patient comorbidities, and indication to treat were analyzed. It was found that prior coronary intervention led to a statistically significant higher rate of symptom reoccurrence (p = 0.036). Additionally, a divergence in the rate of symptom reoccurrence based on indication to treat SAS was noted with the highest rate of symptom reoccurrence in the pre-coronary artery bypass grafting (CABG) group and the lowest rate of symptom reoccurrence in the subclavian steal syndrome (SSS) group. The coronary subclavian steal (CSS) group had an intermediate rate of symptom reoccurrence. During this time period, 1154 CABGs were performed. Flow-limiting stenosis was noted on angiography in 17 of these patients, giving pre-CABG prevalence of 1.46%.