ABSTRACT
BACKGROUND: Respiratory function and pulmonary gas exchange are affected in thoracoscopic procedures where a pneumothorax is introduced using CO2. Carbon dioxide absorption into the blood during thoracoscopic surgery using intrathoracic carbon dioxide insufflation may lead to respiratory acidosis, increased ventilation requirements, and possible serious cardiovascular compromise. In the present study, the effects of propofol on pulmonary gas exchange were compared with those of enflurane in patients undergoing transthoracic endoscopic sympathectomy (TES) during standard tube ventilation with CO2 insufflation to the surgical side in a prospective randomised manner. METHODS: Sixteen patients with ASA physical status I were divided randomly into enflurane or propofol groups. After induction of anesthesia, patients were ventilated in the same mode in each group. Heart rate and mean arterial pressure were checked and blood gas analyses were performed at 3 time points: 10 min after induction of anesthesia (stage 1), 10 min after CO2 insufflation to the surgical side (stage 2), 10 min after CO2 desufflation from the surgical side (stage 3) under two lung ventilation during TES. RESULTS: Arterial oxygen tension (PaO2) did not differ significantly between enflurane and propofol groups and showed no difference among each stage. PaCO2 and end-tidal CO2 (PetCO2) increased significantly at stage 2 compared to stage 1 and then decreased significantly at stage 3 compared to stage 2 (P < 0.05). There were no significant changes in the mean arterial pressure throughout the procedure with CO2 insufflation in both groups, whereas heart rate was significantly lower in the propofol group than in the enflurane group (P < 0.05) at each stage. CONCLUSIONS: This study demonstrates that pulmonary gas exchange in patients with TES using standard tube ventilation with CO2 insufflation to the surgical side is not affected by choice of anesthesia.
Subject(s)
Humans , Absorption , Acidosis, Respiratory , Anesthesia , Arterial Pressure , Blood Gas Analysis , Carbon Dioxide , Enflurane , Heart Rate , Insufflation , Lung , Oxygen , Pneumothorax , Propofol , Prospective Studies , Pulmonary Gas Exchange , Sympathectomy , Thoracoscopy , VentilationABSTRACT
OBJECTIVES: We studied the efficacy and safety of repeated aspiration therapy and minocycline sclerotherapy for cystic thyroid nodules in the euthyroid patients and the factors which might appear to influence the outcome of therapy. SUBJECT AND METHODS: 114 patients with predominantly cystic thyroid nodules were studied. All of the patients underwent the first aspiration therapy, and patients with recurrent cystic lesions after the first aspiration treatment underwent repeated aspiration therapy or additive minocycline sclerotherapy. The patients were followed up ultrasonically 1 and 3 months, and every three month thereafter after the treatments. RESULTS: In 106 patients of 114 patients, cumulative success rate of the treatments was 54.6%. Cumulative success rate of only aspiration treatments(n=81) was 45.1%. 83 patients of 114 patients was recurred after the first aspiration therapy. In these patients, Cumulative success rate of repeated aspiration treatments(n=58) was 24.1%, Cumulative success rate of additive minocycline sclerotherapy(n=25) was 88.0%. Treatment modalities and longest diameter of the lesions significantly influenced the outcome of the trea tments. The effect of the larger longest diameter of cystic thyroid nodule would tend to reduce the cummulative success rate, and the cutoff point of the longest diameter was 4.5 cm. There were no significant adverse effects except for transient pain around the injection site in 12 patients (46%). Cytologic study showed 4 (3.5%) of 114 patients to be malignant. CONCLUSION: Minocycline sclerotherapy of cystic thyroid nodules is a useful and tolerable non-operative therapeutic method in patients with recurrent cystic thyroid nodules after repeated aspiration therapy. The size of a cystic thyroid nodule influence the outcome of aspiration therapy but may not inflcence the outcome of minocycline sclerotherapy.