In 100 morbidly obese patients, neither obesity nor body mass index predicted problems with tracheal intubation. However, a high Mallampati score (greater-than-or-equal to 3) and large neck circumference may increase the potential for difficult laryngoscopy and intubation.

The "ramped" position is superior to the standard "sniff" position for direct laryngoscopy in morbidly obese patients.

No abstract

Preoperative assessment of blood volume (BV) is important for patients undergoing surgery. The mean value for indexed blood volume ((In)BV) in normal weight adults is 70 mL/kg. Since (In)BV decreases in a non-linear manner with increasing weight, this value cannot be used for obese and morbidly obese patients. We present an equation that allows estimation of (In)BV over the entire range of body weights.

Obesity has become a worldwide epidemic in both industrial and developing nations. The precursors of obesity include gender, genetics, environment, ethnicity, education and socioeconomic status. Obesity related medical conditions are reversible following surgical weight loss. Laparoscopy is the preferred operative approach since it is associated with less postoperative pain, earlier recovery and reduced risk of postoperative pulmonary complications. Surgical options currently include either strictly restrictive procedures (vertical banded gastroplasty, adjustable gastric banding) that limit stomach capacity, or operations that combine gastric restriction and malabsorption (Roux-en-Y gastric bypass, biliary-pancreatic diversion, duodenal switch).

M ODERN DISPOSABLE plastic double-lumen tubes (DLTs) are generally safe and easy to use. 1,2 However, a misplaced or improperly used DLT can jeopardize any procedure and even injure the patient. This article reviews considerations for the selection and placement of left-sided DLTs based on data collected from a large series of patients undergoing thoracic procedures requiring one-lung ventilation (OLV) at this institution. Although the information presented represents the authors' experience at a single center, others can apply many of the lessons in their own practices. With the permission of the Human Subjects Committee at Stanford University Medical Center, over an 8-year period from 1993 and 2001, 1,170 consecutive patients undergoing anesthesia for noncardiac, general thoracic surgical procedures were studied. All patients were anesthetized by anesthesia residents under the supervision of one of the authors (JBB). At the time of operation, patient sex, height, weight, site, and type of surgical procedure were recorded. When the patient's chest radiograph (CXR) was available the width of trachea, and in some patients the width of the left bronchus, were measured. The size of the DLT selected, the depth of placement of the DLT in the bronchus, and the volume of air used to inflate the bronchial cuff were recorded. Data are reported as the mean Ϯ standard deviation unless indicated otherwise. Relationships between parameters were analyzed using regression analysis. Any difficulties encountered, complications, or changes in tube position during the procedure were also noted. Data for measured parameters were not complete for some patients.

No abstract

Selective collapse of a lung and one-lung ventilation (OLV) is now performed for most thoracic surgical procedures. Modern double-lumen endobronchial tubes and bronchial blockers have made lung separation safe and relatively easy to achieve. However, OLV in the patient with a 'difficult airway' can present a challenge to the anaesthesiologist. This review considers the different techniques used to achieve lung separation and their application to the patient with a difficult airway.