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One-lung ventilation is used to facilitate thoracic and cardiac surgery. This article describes the development and clinical use of a new device, the bronchial blocker tube, to establish one-lung ventilation. The bronchial blocker tube has two circular lumen joined together, one for ventilation and one for acceptance of a bronchial blocker. In this setting, the bronchial blocker is a separate device which is replaceable, rotatable, and removable. In the authors' experience, the bronchial blocker tube was effective and easy to use.

Patients with abdominal aortic aneurysms (AAA) have a high incidence of associated cardiac disease. If a patient presents with both severe coronary artery disease and a large AAA, a staged procedure of cardiac surgery (CS) followed by AAA resection may present too great a risk of aneurysm rupture and death. A combined procedure may be recommended in this circumstance; however, the literature contains only individual successful case reports of such a procedure. A series of 10 patients who underwent CS and AAA repair to define the risks and outcome of this complex patient population is presented. Methods used included a retrospective analysis of hospital chart data from patients undergoing combined CS and AAA resection from 1980 to the present at this institution. The data analyzed included age, sex, chief complaint, past medical history, indications for surgery, abdominal aneurysm size, coronary anatomy, valvular pathology, preoperative left ventricular function, anesthetic agent and dose, order of surgery, prebypass complications, intraoperative complications, cardiopulmonary bypass time, aortic cross-clamp time, abdominal aortic cross-clamp time, blood product use, and postoperative complications. Seven of the 10 patients had a successful outcome (S group), whereas 3 of the 10 patients died postoperatively (D group). The staged procedure of first performing CS and then the AAA resection has a combined operative mortality of 4%. When the nature of both lesions is severe and a combined procedure is necessary, there is an associated in-hospital mortality of approximately 30% at this institution. The S group patients had an unremarkable postoperative course with a relatively short hospital stay when compared to the staged procedure.

Bilateral sequential lung transplantation is now an accepted therapy for patients with end-stage cystic fibrosis. In our experience, the use of a standard double-lumen endotracheal tube to establish one-lung ventilation during bilateral lung transplantation has been associated with difficulty in clearing the airway of the thick, tenacious secretions characteristically seen in these patients. Intraoperatively, retained secretions have resulted in inadequate ventilation with subsequent hypercarbia, hypoxia, and the need for cardiopulmonary bypass support. We therefore changed our airway management to a single-lumen endotracheal tube combined with a bronchial blocker to establish one-lung ventilation during bilateral lung transplantation. The lumen of a single-lumen tube accommodates larger suction catheters and an adult bronchoscope, which has a larger suction port. We have used this technique in our last five transplantations, finding easier clearing of airway secretions along with markedly improved ventilation compared with management with a double-lumen tube. We recommend this technique of airway management when performing a bilateral single-lung transplantation for end-stage cystic fibrosis.

VATS presents new challenges to the surgeon and anesthesiologist. Although simple diagnostic procedures on the pleura can be performed with local, regional, or general anesthesia with conventional ventilation, more complicated VATS requires general anesthesia with one-lung ventilation. Several techniques can be used to obtain one-lung anesthesia and should be tailored to the patient, proposed procedure, and comfort level of the anesthesiologist. The overall anesthetic management of these patients is similar to those having posterolateral thoracotomies and includes the ability of the anesthesiologist to react to rapid changes in the procedure as well as the overall condition of the patient.

The objective of this study was to evaluate a new reflectance pulse oximeter sensor. The prototype sensor consists of 8 light-emitting diode (LED) chips (4 at 665 nm and 4 at 820 nm) and a photodiode chip mounted on a single substrate. The 4 LED chips for each wavelength are spaced at 90-degree intervals around the substrate and at an equal radial distance from the photodiode chip. An optical barrier between the photodiode and LED chips prevents a direct coupling effect between them. Near-infrared LEDs (940 nm) in the sensor warm the tissue. The microthermocouple mounted on the sensor surface measures the temperature of the skin-sensor interface and maintains it at a present level by servoregulating the current in the 940-nm LEDs. An animal study and a clinical study were performed. In the animal study, 5 mongrel dogs (weight, 10-20 kg) were anesthetized, mechanically ventilated, and cannulated. In each animal, arterial oxygen saturation (SaO2) was measured continuously by a standard transmission oximeter probe placed on the dog's earlobe and a reflectance oximeter sensor placed on the dog's tongue. In the first phase of the experiment, signals from the reflectance sensor were recorded while the dog was immersed in ice water until its body temperature decreased to 30 degrees C. In the second phase, the animal's body temperature was normal, and the oxygen content of the ventilator was varied to alter the SaO2. In the clinical study, 18 critically ill patients were monitored perioperatively with the prototype reflectance sensor. The first phase of the study investigated the relationship between local skin temperature and the accuracy of oximeter readings with the reflectance sensor. Each measurement was taken at a high saturation level as a function of local skin temperature. The second phase of the study compared measurements of oxygen saturation by a reflectance oximeter (SpO2[r]) with those made by a co-oximeter (SaO2[IL]) and a standard transmission oximeter (SpO2[t]). Linear regression analysis was used to determine the degree of correlation between (1) the pulse amplitude and skin temperature; (2) SpO2(r) and SaO2(IL); and (3) SpO2(t) and SaO2(IL). Student's t test was used to determine the significance of each correlation. The mean and standard deviation of the differences were also computed. In the animal study, pulse amplitude levels increased concomitantly with skin temperature (at 665 nm, r = 0.9424; at 820 nm, r = 0.9834; p < 0.001) and SpO2(r) correlated well with SaO2(IL) (r = 0.982; SEE = 2.54%; p < 0.001).(ABSTRACT TRUNCATED AT 400 WORDS)

This study was designed to compare the cardiovascular effects of pipecuronium bromide (PIP) to vecuronium (V) when combined with sufentanil (SF) in patients undergoing coronary artery bypass surgery. Eighty-two patients were studied; 40 were normotensive and 42 had hypertension currently controlled by pharmacological therapy. All patients were randomly assigned to receive either intravenous V, 0.12 mg/kg, or PIP, 0.10 mg/kg. Anesthesia was induced with SF, 6 micrograms/kg, while breathing 100% oxygen. Hemodynamic data including heart rate, mean arterial pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac index, systemic vascular resistance, pulmonary vascular resistance, and left ventricular stroke work index were collected at five points: prior to induction, 3 and 6 minutes after the complete administration of PIP or V, and 3 and 6 minutes after intubation. There were no statistical differences in hemodynamic changes associated with either PIP or V. In addition, there were no statistical differences in the hemodynamic parameters measured at the five time points between the normotensive and hypertensive patient groups. This study demonstrates that there are no significant hemodynamic changes between SF/PIP and SF/V when used during coronary artery surgery. Due to its associated stable hemodynamics, as well as its long duration of action, PIP could become a commonly used muscle relaxant for anesthesia for cardiac surgery.

The relationship between preoperative left ventricular (LV) dysfunction and the use of alpha-adrenoceptor agonists during weaning from cardiopulmonary bypass was studied in 102 patients undergoing coronary artery surgery. LV function was evaluated subjectively by examination of the 30 degree right anterior oblique left ventriculogram. Group 1 consisted of 75 patients with normal or mild impairment in LV function, whereas group 2 consisted of 27 patients with moderate-severe LV dysfunction. Cardiovascular parameters were measured at baseline, during hypothermic bypass with the aorta clamped, during normothermic bypass after unclamping, and 1 and 15 minutes after separation from bypass. Thirty-seven patients in group 1 (49%) and 11 patients in group 2 (39%) required some form of inotropic and/or vasopressor support during weaning from bypass. Group 2 required significantly higher cumulative doses of phenylephrine after bypass compared with group 1 (1.69 +/- 0.70 mg, n = 9, v 0.24 +/- 0.04 mg, n = 27, P less than 0.05). Similarly, the dose of norepinephrine infusion in group 2 was 3.3 times that in group 1 (10 +/- 6 micrograms/min, n = 2, v 3 +/- 0.6 micrograms/min, n = 2, P = NS). The higher doses of alpha-adrenoceptor agonists required in patients with moderate-severe LV dysfunction may be due to differences in alpha-adrenoceptor agonist affinity and/or receptor density.