[Anesthesia for Patients with Obstructive Sleep Apnea Syndrome Associated with Severe Obesity].

A 41-year-old woman with concomitant severe obesity, obstructive sleep apnea syndrome, and asthma was scheduled for endoscopic cholecystectomy. She was 165.8 cm tall and weighed 141.2 kg, with BMI of 51.4. We were concerned with difficulty in ventilation and intubation at the time of anesthesia induction and intra- and post-operative ventilatory failure. After sedation with fentanyl and droperidol together with intraoral local anesthesia with lidocaine (Xylocaine Viscous), the intubating laryngeal mask (ILMA) was inserted while awake, and after the confirmation of adequate ventilation, the bronchoscope was inserted into the guide. Although she received no nerve block, she did not choke at the time of intubation. Because of airway pressure elevation during surgery, volume-controlled ventilation was changed to pressure-controlled ventilation, and, because of a worsening P/F ratio, the recruitment procedure was performed during surgery, with a consequent improvement in the ratio. Although the use of the reservoir and NPPV equipment after extubation was considered, her respiratory status was stable, and she returned to her room with oxygen mask.

[Case report of re-expansion pulmonary edema in a patient with anorexia nervosa after removal of a huge ovarian tumor].

We described a case of 19-year-old female who developed re-expansion pulmonary edema (RPE) after removal of a huge ovarian tumor. Altered lung volume after the surgery was observed by chest X-ray. Preoperatively, the lung was highly compressed by the tumor. Patient was intubated under general anesthesia and was ventilated by pressure controlled mode with only 5 cmH2O of positive end-expiratory pressure (PEEP). P/F ratio was changed from 163 to 444 after removal of the tumor. At the end of the surgery, P/F ratio decreased to 263 with yellow frothy sputum in the endotracheal tube and we diagnosed re-expansion pulmonary edema based on appearing yellow frothy sputum and chest X-ray. No recruitment procedure was carried out through the course except positive pressure ventilation with 5 cmH2O of PEEP in the intensive care unit after surgery. Twelve hours after the surgery, we could not confirm the recovery of lung volume on chest X-ray; however the patient was extubated because of P/F ratio increasing to 507. After 8 days of the surgery, the chest X-ray showed recovery of the lung volume to almost normal size. In this case, the compressed lung needed almost 1 week to recover the lung volume. This change in chest X-ray might indicate inadequate recovery of lung volume by recruitment maneuver and this should be avoided in order not to allow development of unfavorable clinical course of RPE.

[A case of malignant hyperthermia with evident symptoms in the postoperative period].

A 36-year-old man (185 cm tall, weighing 85 kg) was scheduled for fixation of a right carpal bone fracture. He had no operative history, and his preoperative laboratory data were normal. A laryngeal mask was inserted after intravenous propofol and fentanyl administration without a muscle relaxant. Anesthesia was maintained by sevoflurane in a mixture of air and oxygen. A tourniquet was placed on the right upper arm. One hour after the operation, his heart rate increased to 90-100 beats x min(-1) from 70-80 beats x min(-1) at the start of the operation, and tachycardic continued, even after release of the tourniquet. Although end-tidal CO2 was 50-60 mmHg, his body temperature remained 37.6 degrees C, and neither muscle stiffness nor brown urine was observed. The duration of the operation and the duration of anesthesia were 2 hours 40 min and 4 hours, respectively. The patient went back to the ward without myalgia after removal of the laryngeal mask. On the postoperative day one, the patient had brown urine. On the postoperative day 2, he experienced myalgia of the upper and lower extremities and masseter muscle. On the postoperative day 3, myoglobinuria was detected. As in this case, although evident symptoms of malignant hyperthermia are not always observed during operations, some cases show obvious symptoms during the postoperative period. Thus, it is important to be aware of the symptoms of malignant hyperthermia postoperatively for early diagnosis and treatment.

Simultaneous control of turbidity and dilution rate through adjustment of medium composition in semi-continuous Chlamydomonas cultures.

For production of starch in algal cultures, a growth rate limited by a nutrient is an important factor. Under phototrophic conditions, turbidity must be also paid attention, as the shading effect may affect its productivity. Semi-continuous cultivation methods, which enable control of turbidity and dilution rate (D) at the same time, have been developed for evaluation of those factors on starch production in Chlamydomonas sp. A specific feature of the methods is in a process of alternately feeding medium adjusted at two different nitrogen (N) concentrations. In the turbidostat-based method, a turbidostat culture was operated repeating three steps of determining D within a preset interval, alternating media by comparing the D with a preset value, and adjusting D in the next interval by feeding the selected medium. In the chemostat-based method, turbidity of a chemostat culture was controlled by repeating two steps of alternating media by comparing transmitted photon flux intensity (I) with a preset value and adjusting I by feeding the selected medium. D controlled by the turbidostat-based method reached quickly a preset value as low as 0.010/h, and then it was dispersed around but above the preset value. On the other hand, mean N concentrations of fed media formed a plateau. In the chemostat-based method, I was well controlled to a preset value while the mean N concentrations were a bit fluctuated. Starch concentration varied from 0.052 to 0.41 g/L with turbidity and D defined by these methods.