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Examination of the literature suggests that the incidence of aspiration pneumonia in the perioperative period is relatively infrequent. Since Mendelson's report of aspiration pneumonitis in 1946, the factors that contribute to the likelihood of aspiration have been identified, and numerous attempts for preventions for regurgitation or pulmonary aspiration have been made. The low incidence of major morbidity of anesthesia-related pulmonary aspiration may be due to adopting quality measures, applying practice guidelines for preoperative fasting, and the use of pharmacologic agents to reduce the risk of pulmonary aspiration. More systematic preoperative checking and more careful selection of patients are necessary when a supraglottic airway is used in preference to a tracheal tube. Second generation supraglottic airways may not reduce the risk of regurgitation, but may reduce the chance of aspiration if the mask position is correct and drain tube works well. Because the mortality and morbidity of aspiration pneumonia remain relatively high, the preoperative risk evaluation is very important to avoid regurgitation or aspiration.

A 35-year-old parturient, 35 weeks pregnant, pre- sented with intracranial tumor with increased intracra- nial pressure. She underwent emergency cesarean section under general anesthesia, followed by craniotomy. The intraoperative and postoperative courses were uneventful. The occurrence of brain tumors during pregnancy is very rare; meanwhile pregnancy may aggravate the natural history of an intracranial tumor, and may even unmask previously unknown diagnosis. The decision to proceed with cesarean section and neurosurgery depends on the site, size, type of tumor, neurological signs and symptoms, age of the fetus, and the patient's wishes. Therefore, close communication between the neurologist, neurosurgeon, anesthesiologist, obstetrician and the patient is very important.

We describe two cases which developed loss of motor evoked potentials from bilateral lower limbs following thoracoabdominal aortic repair. Paraplegia was suspected in both cases; however, one case of Crawford type 2 aneurysm showed transient left leg monoplegia with a sensory deficit and the other case of aortic pseudoaneurysm showed no neurologic dysfunction postoperatively. We employed epidural cooling and spinal drainage for spinal protection and distal perfusion was provided through aorto-iliac side-arm conduit. Despite the prolonged spinal ischemia during thoracoabdominal aortic repair, spinal drainage and epidural cooling were very helpful for protecting the spinal cord from ischemia. The interpretation of MEPs seems very difficult especially when the potentials remain absent even after reconstruction or reperfusion of segmental arteries, because variety of intraoperative factors may affect them.

We describe a 50-year-old man who developed ventricular arrhythmia followed by cardiac arrest during laparoscopic distal gastrectomy. Preoperatively, there were no findings suggesting an ischemic heart disease. Anesthesia was maintained using sevoflurane combined with epidural anesthesia. His blood pressure, heart rate, and ECG waves were stable during the initial stage of laparoscopic procedure. After establishment of small laparotomy for stomach resection, the blood pressure decreased to before 60 mmHg without remarkable ST change on lead II. Administration of intravenous ephedrine was not effective and a short run appeared. Then persistent ventricular tachycardia followed by ventricular standstill developed. Chest compression and intravenous adrenalin restored sinus rhythm, and thereafter the patient remained hemodynamically stable with intravenous nitroglycerine and nicorandil. The operation was completed and the patient awoke without neurological deficits. Postoperatively the coronary angiography showed no stenosis of coronary arteries; however, when acetylcholine test was attempted on right coronary artery, paroxysmal ventricular fibrillation in accordance with spasm of #1 segmental coronary artery developed. In the case of abrupt onset of lethal arrhythmia, coronary vasospasm should be suspected even when ST changes are not recognized with routine ECG monitor.

Epidural anesthesia is widely used in patients who undergo thoracic, abdominal or lower extremity surgeries and generally considered useful for perioperative analgesic management. Epidural catheterization is often associated with some complications including misplacement of the catheter. Epidural catheters are known to be misplaced or migrate into subarachnoidal space, subdural space, vessels and thoracic cavities ; however, frequency, predominant sites of misplacement, and the timing of detection are not fully understood regarding the misplacement of the catheters. In this retrospective study, our incident reporting system dealt with a period of 8 years (from 1999 to 2007) at our university hospital. Out of 8 patients who had misplacement of the catheter, 6 patients were male and 2 patients were female. Epidural catheters were misplaced to subarachnoid space in 6 cases and thoracic cavity in 2 cases. The misplacement of the catheters was found before the induction of general anesthesia in 2 patients, after induction of general anesthesia in 1 patient, during surgical procedure in 3 patients, and postoperatively in 2 patients. Since misplacement of epidural catheters can occur at any moment during perioperative period, continuous monitoring and observation of patients seem to be very important to prevent and minimize the adverse events related to the misplacement of epidural catheters.

A patient developed anaphylactic shock after a heparin dosage during an operation to make inner shunt for chronic renal failure of Alport syndrome. The operation was canceled and the patient was admitted to the ICU with tracheal intubation. He was extubated safely on the fifth postoperative day, but he lost the sense of smell from the day after. Abnormality of the nasal mucosa was not recognized. The smell disorder improved slowly in three or four weeks. Anosmia after anaphylactic shock is very rare, but we should be careful for this complication after anaphylactic shock.

Background: Since the establishment of Model Core-Curriculum for Medical Education in 2001, undergraduate medical education has been progressively renovated in Japan. We conducted a questionnaire survey to investigate how this curriculum changed undergraduate anesthesiology education and how it affected our work load as the teaching staff of medical schools., Methods: The questionnaire sent to 80 medical universities in Japan, consisted of 4 parts; (1) activity of institution and human resources, (2) lectures, (3) clerkship, and (4) future direction of the lectures and clerkship., Results: The response rate was 59%. The number of staff engaged in undergraduate education was variable; ranging from 4 to 28. The number of lectures was 0 to more than 25 units per year and 6 institutions discontinued conventional didactic lectures. Although clinical clerkship program was being offered to students in most institutions, informed consent for clinical procedures by the students was obtained only in 11 of 47 institutions., Conclusions: The result shows that there is still room for improvement in educational environment, including manpower or curriculum. A written informed consent should be completed to provide patients' safety and to fulfill the clinical practice by medical students.

A 30-year-old woman was scheduled to undergo hysteroscopic myomectomy for uterine myoma. Spinal anesthesia was performed with 3 ml of 0.5% bupivacaine and she was sedated with intravenous propofol during the surgery. After the surgical procedure, propofol infusion was stopped. The patient soon awoke and vomited frequently and repeatedly. Her serum sodium concentration was as low as 129 mEq x l(-1) and fluid overload (water intoxication) was suspected. Because the abdominal X-P revealed that two parts of the surgical instrument remained in her uterine cavity at that time, hysteroscopic procedure was restarted. General anesthesia was induced with propofol and maintained with nitrous oxide and sevoflurane. During the procedure, uterus was accidentally perforated and one of the parts moved into the abdominal cavity. When the laparotomy started to fix uterine perforation, the abdomen of the patient became remarkably distended. During the laparotomy, it was revealed that 4800 ml of irrigation fluid had been accumulated in the abdominal cavity. Although hysteroscopic surgery is generally considered non-invasive, two major complications (fluid overload and uterine perforation) occurred in this case. This case suggests that anesthetists must remain alert for the signs of these complications during hysteroscopic surgery.

A 59-year-old man with paroxysmal nocturnal hemoglobinuria (PNH) underwent an operation for lumbar disk herniation. He was given warfarin, aspirin, and steroid for PNH and suspected venous thrombosis. PNH is a hemolytic anemia due to an acquired red blood cell membrane defect at the stem cell level. The patient with PNH has a risk of massive hemolysis induced by stresses such as acidosis, fever, operation, trauma and overfatigue. Other main symptoms of PNH are venous thrombosis and deficient hematopoiesis. We prevented massive hemolysis by increasing the dose of steroid and avoiding acidosis, fever and dehydration during the perioperative period. Warfarin and aspirin were changed to dalteparin before operation for the prevention of venous thrombosis as well as for easy control of bleeding tendency. The perioperative course was uneventful without obvious hemolysis, venous thrombosis and unnecessary bleeding.

A 13-month-old girl with cyanotic congenital heart disease; single atrium, single ventricle, common atrioventricular (AV) valve, pulmonary atresia and total anomalous pulmonary venous drainage, suspected of asplenia underwent ear tube surgery for otitis media. She had undergone bilateral Blalock-Taussig shunts for her heart disease. She had congestive heart failure due to moderate to severe common AV valve regurgitation and often experienced respiratory tract infection with sputum. Oxyhemoglobin saturation measured by pulse oximetry was 75-80% and polycythemia was found in complete blood count. We chose tracheal intubation for her airway management because of a large amount of sputum. General anesthesia was maintained with sevoflurane, nitrous oxide and oxygen for ear tube surgery. During anesthesia she showed several episodes of desaturation which were well managed by frequent tracheal suctioning. Her circulation was stable with 50% N2O and sevoflurane 1.7-2.0%. The operation was performed uneventfully and the patient was discharged to the ward after tracheal extubation. Asplenia is frequently complicated with cyanotic congenital heart disease and increased susceptibility to bacterial infection. Anesthesia for these patients with upper respiratory infection should be managed with tracheal intubation even for a short surgery.

Heparin-induced thrombocytopenia (HIT) type II is characterized by a decrease in platelet count and thrombosis following heparin administration. We anesthetized a 67-year-old woman with suspected HIT type II undergoing carotid endarterectomy (CEA). Preoperatively, the patient had received anticoagulation therapy with heparin for cerebral infarction due to thrombosis and she developed thrombocytopenia with deterioration of cerebral infarction. Platelet level recovered by discontinuation of heparin and platelet infusion. During the surgical procedure, a substitution for heparin as an anticoagulant was necessary and we used argatroban, a direct thrombin inhibitor, with monitoring activated coagulation time (ACT). The ACT values were maintained above 200 sec during endoarterectomy and the operation was successfully carried out. We believe that argatroban is one of the choices for anticoagulants in a patient with HIT type II.

A 64-year-old woman was admitted to our hospital for removal of a thoracic tumor. Chest X-ray and computed tomography demonstrated a giant thoracic tumor occupying the right thorax, with the right lung almost completely collapsed and the mediastinum shifted to the left. Her preoperative pulmonary function studies revealed %vital capacity of 30%, and her oxyhemoglobin saturation was 92% (room air). Anesthesia was maintained with sevoflurane and fentanyl. The trachea was intubated with an armored tube because of severe tracheal shift. Operation was performed in the supine position. A Swan-Ganz catheter was inserted from the right femoral vein under fluoroscopy with stand-by of percutaneous cardiopulmonary support. The tumor was removed segmentally, and her right lung was inflated gradually. Two hours after removal of the tumor, PaO2 decreased to 74.2 mmHg (FIO2 1.0), and a large amount of sputum was suctioned subsequently. We suspected re-expansion pulmonary edema (RPE) and administered steroid with frequent tracheal suctioning. The patient was transferred to ICU without extubation. Postoperative X-ray demonstrated diffuse alveolar infiltrates over the right lung field. The patient was followed by respiratory management and body fluid management with diuretic drugs. The trachea was extubated on the following day, and her postoperative recovery was uneventful thereafter. We should consider the occurrence of RPE at removal of the giant thoracic tumor.

This report summarizes our experience with the use of epidural cooling for protecting spinal cord ischemic injury in patients receiving thoracoabdominal aortic surgery. Of 8 cases with thoracoabdominal aortic surgery, we used epidural cooling in 5 cases. Epidural cooling was performed through an epidural catheter placed at Th 11 x 12 using chilled saline. Spinal cord temperature was maintained at approximately 28 degrees C. None of the 5 cases had paraplegia or paraparesis whereas two of 3 cases without epidural cooling had permanent paraplegia. In one case with paraplegia, we could not detect any changes in spinal evoked potential until the end of graft anastomosis. We monitored motor evoked potential in the recent 2 cases. We believe that epidural cooling combined with motor evoked potential monitoring appears to be a satisfactory strategy for preventing ischemic spinal cord injury in thoracoabdominal aortic surgery.

The efficacy of gas exchange during partial liquid ventilation (PLV) may be affected by positive end-expiratory pressure (PEEP), tidal volume (TV) and perflubron (PFOB) dose. The purpose of the present study was to clarify which factors were important for improving gas exchange during PLV. Fourteen rabbits were anesthetized and tracheostomized. Lung was introduced with intravenous oleic acid combined with saline lung lavage. After obtaining control data, PFOB 7.5 ml.kg-1 was instilled into the trachea, and ventilation settings were changed sequentially [1. TV: 10 ml.kg-1 (mTV), 2. mTV with PEEP, 3. TV: 15 ml.kg-1 (hTV), 4. hTV with PEEP]. PEEP level was set to the lower inflection point. The PFOB dose was increased to 15 ml.kg-1 and measurements were repeated under each ventilation setting. PEEP increased PaO2 in all ventilation settings. In hTV ventilation settings, incremental dose of PFOB significantly increased PaO2. The PaO2 values of all hTV ventilation settings were significantly higher than those of corresponding ventilation setting of mTV. Pulmonary compliance was significantly decreased with PEEP in hTV ventilation in addition to 15 ml.kg-1 PFOB. The results suggested that adequate gas tidal volume was the most important factor for improving gas exchange during PLV. However, PEEP or larger dose of PFOB should be avoided because they may decrease pulmonary compliance.

A multicenter study was performed to evaluate the success of endotracheal intubation using an intubating laryngeal mask (ILM, Fastrach) in patients in ASA status I or II, aged 20 years or more, who underwent general anesthesia. A total of 191 patients were studied, and 24 of them were estimated difficult to intubate by the ordinary method with laryngoscope. Endotracheal intubation was successfully performed through ILM in 162 of the 191 (success rate of 84.8%). The mean time required for intubation in these successful cases was 19.1 seconds. The success rate did not depend on the clinical experience of anesthesiologists, and the individual success rate was improved as they became more experienced. Of the 24 patients who had been estimated difficult to intubate with laryngoscope, 23 were successfully intubated with success rate of 95.8%. In summary, endotracheal intubation through ILM was easy regardless of the anesthesiologist's experience, and seemed to be valuable for patients who were difficult to intubate.

We evaluated the usefulness of the intubating laryngeal mask airway (ILMA) in patients who were predicted to have possible difficult airway. Patients with possible difficult airway were defined as those with limited head extension, Mallampati's classification of grade IV, thyro-mental distance < 4 cm, or Cormack grade III-IV on the laryngoscopy. The control group was consisted of the patients without these conditions or impaired mouth opening. Insertion of the ILMA was successfully performed in all patients of both groups. In the group of possible difficult airway, 83% of patients were intubated through the ILMA successfully, and in the control group, 86%. We conclude that the ILMA may become an additional tool in patients with difficult intubation.

A patient with protein C deficiency associated with massive pulmonary embolism underwent open heart tromboembolectomy. The operation was successfully performed under cardiopulmonary bypass using a usual dose of heparin 3 mg.kg-1. The effect of heparin was successfully reversed by the administration of protamine sulfate 6 mg.kg-1. Perioperative administration of fresh frozen plasma or protein C concentrates might be necessary to manage hypercoagulability in a patient with protein C deficiency.

The effect of thiopental and sevoflurane (1 MAC, 2 MAC) on hemodynamics was assessed in a randomized study involving 38 adult patients undergoing electroconvulsive therapy (ECT). Blood pressure, heart rate and electrocardiogram (ECG) were monitored during the ECT procedure. After oxygenation, hypnosis was induced with a bolus injection of thiopenal (TPS) 4 mg.kg-1. Muscle relaxation was achieved by succinylcholine, 1 mg.kg-1 intravenously before ECT procedure. Ventilation was assisted using a face mask with 100% oxygen (TPS group), 1.7% sevoflurane (1 MAC group) or 3.4% sevoflurane (2 MAC group), plus 50% nitrous oxide and 50% oxygen. Thereafter, an electrical stimulus was administered. A total of 150 treatment sessions were evaluated. The rate pressure product increased in every group right after ECT, but the use of sevoflurane (2 MAC) significantly diminished the response compared with sevoflurane (1 MAC) and thiopental. In the sevoflurane (2 MAC) group, no ventricular arrhythmias were observed. In general, it seems that sevoflurane (2 MAC) is as effective as thiopental and sevoflurane (1 MAC) as an induction agent for ECT.

Perioperative airway management for sleeve pneumonectomy in a 66-year-old female with tuberculous tracheal stenosis which was 2 cm above the carina to the right main bronchial orifice is reported. Endotracheal intubation was required, because she complained of dyspnea due to airway stenosis in preoperative period for anti-tuberculous chemotherapy. A special tracheal tube developed for laryngomicrosurgery (MLT tube, Mallinckrodt Co. Ltd., 21 Fr size) was used in this patient. However, 13 days after intubation with an MLT tube, sleeve pneumonectomy was done because because of right lung atelectasis and progressive hypoxemia. Left one lung ventilation was successful by an MLT tube during right thoracotomy and a spiral tube (28 Fr) was inserted to the left main bronchus in the operative field during the resection of the carina. For this type of patient with tracheo-bronchial stenosis, it is essential to select an endotracheal tube with appropriate length and diameter.

The effects of cervical epidural morphine and buprenorphine on postoperative pain were studied in 12 patients who received thoracic surgery twice. The patients who had received morphine 3 mg on the first operation were given buprenorphine 0.15 mg on the second operation, and the others received them vice versa. Morphine or buprenorphine was administered with 6 ml of 0.25% bupivacaine before skin incision. The duration of pain relief with morphine was longer (21.5 +/- 4.0 h) than with buprenorphine (13.9 +/- 7.8 h). The result of the questionnaires to the patients after operation shows that 10 patients (84%) were satisfied with morphine whereas only 6 patients (50%) were satisfied with buprenorphine. Seven patients preferred morphine to buprenorphine for postoperative analgesia, and the rest of the patients stated that analgesic effects were similar between the two. It seems that epidural morphine 3 mg may give more excellent postoperative pain relief after the thoracic surgery than epidural buprenorphine 0.15 mg.