[Simple Formula to Predict Residual Amount of Continuously Infused Rocuronium in the Body].

BACKGROUND: When antagonism is performed using sugammadex after continuous infusion of rocuronium, if the total amount of residual rocuronium can be esti- mated prior to performing antagonism, antagonism without excess or deficiency of sugammadex will be made possible. We therefore prepared a simple formula to predict residual amount of rocuronium in the body, which can be easily applied in clinical setting, and veri- fied it using Tivatrainer©. METHODS: 1. Pharmacokinetics of rocuronium was simulated, using a 3-compartment model. The following assumptions were made to derive the simple for- mula : when rocuronium is continuously infused to reach the steady state plasma concentration, an equal concentration in each compartment is reached. Only the amounts of rocuronium infused to the central com- partment and rocuronium excreted from there are thus considered, and these two amounts are in balance. For pharmacokinetic parameters, we referred to V. Saldien, Anesth Analg 2003 ; 97 : 44-9. 2. The prepared simple formula was verified using Tivatrainero. We considered a model in which initial boluses of 0.3, 0.6, 0.9, and 1.2 mg · kg(-1) were adminis- tered, and continuous infusion began at 30 minutes at the rate of 0.2, 0.3, 0.4, 0.5, 0.6, and 0.8 mg - kg-1 - hr-1. Patients with body weight of 50, 60, 70, and 80 kg were investigated. RESULTS: 1. The derived simple formula was as fol- lows : Q=0.74 X R Q Total residual amount of rocuronium (mg) R Dose per hour (mg · hr(-1)) 2. The predicted value of the total residual amount obtained from the simple formula was consistent with the value predicted by Tivatrainer© with a high preci- sion within the error of 1.4%. Convergence time until the stable state was reached varied depending on the condition. However, it took approximately 150 minutes after the beginning of continuous infusion.for the error between values predicted by the simple formula and Tivatrainer© to stabilize within 5 mg. CONCLUSIONS: We prepared a simple formula to esti- mate the total residual amount of rocuronium at a steady state. The value predicted by the simple for- mula agreed with the value predicted by Tivatrainer) with a high precision.

Analysis of prehospital endotracheal intubation performed by emergency physicians: retrospective survey of a single emergency medical center in Japan.

OBJECTIVES: Advanced airway management in the prehospital setting is a serious issue in Japan because emergency medical technicians are not authorized to perform such management, whereas physicians-who are authorized to perform advanced airway management-do not usually engage in prehospital emergency medical activity. The purpose of this investigation was to investigate the success rate for endotracheal intubation (ETI) procedures and other methods of airway management employed by physicians in the prehospital setting in a single institution, as well as to examine the risk factors associated with difficult or failed endotracheal intubation (D/F ETI). METHODS: We performed a retrospective survey of patients treated in the prehospital setting by emergency physicians of the Hyogo Emergency Medical Center from 2004 to 2011. Patients were divided into two groups: a cardiopulmonary arrest (CPA) group and a non-CPA group. Data on cases of D/F ETI were obtained, and risk factors for these two groups were identified using univariate and statistical analysis. RESULTS: During the investigation period, ETI was attempted in the prehospital setting on 742 eligible patients; in 30 (4.04 %) of these cases, the attempts at ETI proved difficult or failed. Of those 30 patients, 13 patients received a surgical airway (attempts to provide a surgical airway failed in two patients), a blind ETI was performed in four, a video-assisted airway device was used in another four, and esophageal intubation was performed in four patients. Bag-valve ventilation alone was performed in one patient. The incidence of D/F ETI was higher in the non-CPA group than in the CPA group (6.27 vs. 2.63 %: p < 0.05). Facial or neck injury was a risk factor for D/F ETI in the prehospital setting in the CPA group (odds ratio 7.855; 95 % CI 1.754-36.293: p = 0.042). On the other hand, no risk factors for D/F ETI in the prehospital setting in the non-CPA group were identified. CONCLUSION: The success rate for ETI performed by physicians in the prehospital setting at a single emergency medical center was high, and the incidence of D/F ETI was 4.31 %. The success rate for ETI in the CPA group was greater than that in the non-CPA group.

[Difficult mask ventilation and tracheal intubation in a patient with Hutchinson-Gilford syndrome].

We report a case of difficult ventilation and tracheal intubation in a 18-year-old woman with Hutchinson-Gilford syndrome. She was diagnosed with osteosarcoma in the right tibia and thyroid cancer. She was scheduled for two operations under general anesthesia for the bone tumor and the thyroid. In the operation, we experienced difficult mask ventilation and tracheal intubation because of her small mouth, small mandible and narrow upper airway related to Hutchinson-Gilford syndrome. In the second operation, mask ventilation and tracheal intubation were easily conducted by using Berman pharyngeal airway. Berman airway was useful for airway managemant of Hutchinson-Gilford syndrome.

[Case of postoperative paraplegia caused by idiopathic spinal cord infarction in a young male patient].

We report a case of spinal cord infarction in a 20-year-old man, who underwent abdominal surgery under general anesthesia combined with epidural anesthesia. The patient was a healthy young man with no medical history. After the operation, he complained of weakness and sensory blockade of both legs. MRI revealed spinal cord infarction at the T9-10 vertebral levels. Steroid pulse therapy was introduced, and paraplegia almost disappeared. Spinal cord infarction in a young man is very rare, but should be considered in case of postoperative paraplegia even in a young patient.

Preoperative elevated FDP may predict severe intraoperative hypotension after dural opening during decompressive craniectomy of traumatic brain injury.

PURPOSE: Coagulation disorder and intraoperative hypotension are representative complications of traumatic brain injury which cause worse perioperative outcome. The aim of this study was to survey the relation of coagulation disorder and intraoperative hypotension (IH) during decompressive craniectomy. METHOD: Patients who underwent emergency decompressive craniectomy due to traumatic brain injury were retrospectively surveyed. The relation between preoperative coagulation date and intraoperative hypotension (systolic blood pressure < 60 mmHg after dural opening) was analyzed. RESULTS: Of 41 patients screened, 12 patients (27.9%) developed IH. Fibrinogen degradation products (314 vs 64.4 µg/mL; p = 0.01) were significantly higher in the IH group. In contrast, fibrinogen (181 vs 239 mg/dL; p = 0.01) was significantly lower in the IH group. Reduction rate of sBRP before and after dural opening (%) was higher in IH group than in non-IH group (49.1 vs 27.6%: p = 0.001). CONCLUSIONS: Preoperative elevated FDP may predict IH after dural opening during traumatic decompressive craniectomy.

[Management for the removal of dopamin-secreting pheochromocytoma].

Incidence of dopamin-secreting pheochromocytoma is very rare. We reported managment of anesthesia for the removal of dopamin-secreting pheochromocytoma. A 46-year-old woman was diagnosed with pheochromocytoma, but lacking clinical symptoms. Plasma and urinary dopamine levels were remarkably elevated, but other catecholamine levels were within normal limits. She underwent left adrenalectomy. Plasma dopamine was measured before during and after the adrenalectomy. Blood pressure was not related to plasma dopamine levels.

[Management of one lung ventilation with bronchial blocker catheter for a patient with tracheobronchopathia osteochondroplastica].

Tracheobronchopathia osteochondroplastica is a rare benign disease, with difficult airway for intubation because the trachea and bronchia are narrow and transformed. We experienced one lung ventilation for a patient with the lung cancer associated with the tracheobronchopathia osteochondroplastica. The Coopdech bronchial blocker is a device for one lung ventilation. We could actually manipulate the blocker balloon very easily and maintain complete one lung ventilation maintaining SpO2 well. Coopdech bronchial blocker is useful for one lung ventilation in a patient with difficult airway such as tracheobronchopathia osteochondroplastica.

[Tracheal intubation for two patients with lingual tonsil hyperplasia and prospect of difficult airway management].

Lingual tonsil hyperplasia is rare, but may cause difficult or inpossible tracheal intubation. We experienced two cases of tracheal intubation for lingual tonsil hyperplasia. A 71-yr-old man was scheduled for resection and biopsy of symptomatic hypertrophied lingual tonsils. In this patient, we performed oro-tracheal intubation by rigid laryngoscopy from left oral angle, because left hypertrophied lingual tonsils are smaller than those on the right side. A 44-yr-old man was scheduled for resection of symptomatic hypertrophied lingual tonsils after lingual tonsillitis. In this patient, we performed nasotracheal intubation using fiberoptic bronchoscopy with assist of jaw-lift and tongue-extension. When an anesthesiologist can predict the abnormality of lingual tonsils, these methods might be recommended for difficult airway and intubation. However, it is necessary to prepare a difficult airway management set including laryngeal mask airway, intubating laryngeal mask airway, fiberoptic bronchos-copy and transcutaneous tracheotomy set. And most important is preliminary evaluation of airway and cautious planning of tracheal intubation.

[Management of maternal tetanus contracted by an obstetric procedure].

A 34-year-old woman from the Philippines showed difficulty in opening the mouth. She had no wounds in the last one mouth, but was treated with an obstetric procedure after stillbirth 16 days before in the Philippines. She showed trismus, rigidity and muscle pain, but no muscle spasms, dyspnea and autonomic dysfunction. In this case, it is supposed that the obstetric procedure is the origin of the injury. In Japan, this is the first report of maternal tetanus.

[Pneumothorax during esophageal endoscopic mucosal resection].

We report a case of pneumothorax occurring during esophageal endoscopic mucosal resection (EEMR). A 53-year-old man with early esophageal carcinoma was scheduled for EEMR under general anesthesia with artificial ventilation. During the operation, arterial oxygen saturation measured by pulse oximeter suddenly decreased from 99% to 84%, and airway pressure increased from 15 cmH2O to 25 cmH2O. Right pneumothorax was detected and chest drainage was performed. On resumption of the operation, perforation of the esophagus was identified and repaired. The esophageal perforation and pleural injury were thought to have been caused by endoscopic operation. Although a rare complication in EEMR, pneumothorax should be considered when sudden' hypoxia occurs during EEMR.

Petechial and subcutaneous hemorrhage with blister formations in right upper extremity during cardiopulmonary bypass by axillary artery cannulation.

A 72-year-old man underwent aortic valve replacement and coronary artery bypass graft using cardiopulmonary bypass with right axillary artery cannulation. After undraping, petechial and subcutaneous hemorrhage with blister formations were found in right upper extremity. Axillary artery cannula was considered to compress right subclavian and disturb venous return in the right subclavian vein, which caused an acute compartment syndrome during cardiopulmary bypass. This case was a rare,but severe complication of cardiopulmonary bypass with right axillary artery cannulation.