[Use of propofol during laser therapy of the tracheobronchial tract]. / Impiego del Propofol durante laserterapia delle vie tracheobronchiali.

Anesthesia of the tracheobronchial (TB) pathways during laser therapy (LT) faces a variety of problems including analgesia and sedation in patients with respiratory difficulties or who continue to breathe spontaneously while the airways are occupied by operating instruments. During the course of the study, two methods of anesthesia were compared in 36 patients undergoing LT of the TB pathways. The first method (Group A, n = 16) involved the use of Diazepam as an hypnotic starter and Fentanyl as an opioid analgesic in continuous infusion. Propofol was used both as an inducer and as the main drug in the second method (Group B, n = 20) in order to reduce the opioid dose required. The following variables were studied: heart rate, systolic and diastolic blood pressure, blood gas analytic parameters, side-effects such as cough and intraoperative movement, and disturbances of heart rhythm and conduction; in addition, the duration of operations and the time taken to regain consciousness were recorded, together with the total dose of Fentanyl used. An improved hematosis was observed in patients treated with Propofol during the operation and on regaining consciousness, and the time taken to regain consciousness was significantly reduced. No significant differences were observed between the two groups with regard to cardiocirculatory variables or undesirable effects.

[The transcutaneous method of monitoring partial pressure of O2 and CO2 during laser surgery of the trachea and bronchi]. / La metodica transcutanea nel monitoraggio della tensione parziale di O2 e CO2 durante laserterapia delle vie tracheobronchiali.

Anesthesia during Nd-YAG laser resection of the airways necessitates continuous O2 and CO2 monitoring. Although only partial, monitoring may be performed using a transcutaneous method utilising Clark's electrode to measure O2 and Stowe-Severinghaus' electrode to assess CO2 on the skin surface. The paper evaluates the advantages and limits of this form of monitoring during anesthesia in 85 patients undergoing laser resection of the airways. In conclusion, in spite of the fact that it is currently impossible to build up a complete picture of blood gas status from a single transcutaneous finding, the use of the transcutaneous method increases the level of safety of the operation as a whole.

Nd:YAG laser bronchoscopy. A five-year experience with 1,396 applications in 1,000 patients.

We treated 1,000 patients with the Nd:YAG laser. The rigid bronchoscope was used in 1,280 (92 percent) of the treatments, with patients almost always under general anesthesia; 116 (8 percent) treatments were performed with the flexible fiberoptic bronchoscope alone, with the use of local anesthesia. In almost all cases of benign tumors and in many carcinoid tumors, the treatment was curative. In genuine nonmalignant tracheal stenoses, laser therapy was curative in 34 out of 81 cases. In malignant tumors, the laser improved airway gauge 92 percent of the time. Cumulative survival was 50 percent (+/- 3 percent) at six months and 26 percent (+/- 3 percent) at one year. Following palliative laser therapy, eight patients with bronchogenic carcinoma appearing to be inoperable did have surgery and ten underwent less extensive surgery than expected. Results confirm the usefulness and safety of this relatively new method in the treatment of obstructive lesions of the tracheobronchial tree.

Pharmacokinetics of atenolol in hypertensive subjects with and without co-administration of chlorthalidone.

The pharmacokinetics of atenolol with and without the co-administration of chlorthalidone were studied in five hypertensive subjects. Concomitant administration of chlorthalidone appears to have little if any effect on the pharmacokinetics of atenolol during treatment for 7 days. The atenolol elimination half-lives were 6.7 +/- 1.1 and 6.3 +/- 0.9 h, respectively, with and without chlorthalidone. Two healthy volunteers also received a single 50 mg oral dose of chlorthalidone. Their blood profiles and pharmacokinetics were similar to those observed in hypertensive subjects, but a statistically significant difference (p < 0.01) was found between the urinary excretion half-lives of chlorthalidone. This difference may be because chronic administration of the drug caused saturation of red cell binding.