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Amyotrophic lateral sclerosis (ALS) is a degenerative disease of motor ganglia in the anterior horn of spinal cord and spinal pyramidal tracts. The impairments of respiratory function and weakened upper airway muscle affect anesthetic management. General anesthesia may cause respiratory problem. Regional anesthesia such as spinal and epidural anesthesia is also relative contraindication for patients with a motor neuron disease, including ALS, for the fear of exacerbating the disease. Therefore patients with ALS are needed careful management during perioperative period. We report a case of epidural anesthesia for transurethral ureteroscopic lithotripsy in a patient with ALS. The patient recovered from anesthesia without exacerbating the disease.

An 11-year-old boy underwent thoracolumbar surgery to correct a deformity caused by congenital kyphoscoliosis from the 6th thoracic vertebra to the 2nd lumbar vertebra. During a screw insertion, some tore and cerebro-spinal fluid (CSF) leaked. After CSF leakage, the amplitude of the motor evoked potential in the left lower extremity was reduced by 90% compared to baseline value, but there was no nerve damage at the surgical site. His post-surgical mental status did not recover completely. Brain computed tomography revealed a subdural hemorrhage in the inter-hemispheric fissure, with both tentorium and right frontotemporooccipital and diffuse brain edema. On the 4th postoperative day, mental status recovered to near alertness, but upper motor strength was grade II, right lower motor strength was grade II and left lower motor strength was grade I. Right hemifacial palsy was also noted. At 2.5 months after surgery, right facial palsy remained, but motor function recovered to near normal levels with conservative care.

Background During sedation with dexmedetomidine, a dose adjustment may be needed based on the invasiveness of the procedure, the patient's general condition, and their age. We aim here to determine the effective dose (ED) of dexmedetomidine to induce an adequate depth of sedation in elderly patients undergoing spinal anesthesia. Methods In this study, 47 patients aged 65 years or older, American Society of Anesthesiologists physical status I or II, undergoing spinal anesthesia were included. Patients were randomly allocated into group I, II, III, IV or V according to the dexmedetomidine loading dose of 0.1, 0.3, 0.5, 0.7 and 1.0 µg/kg, respectively. After spinal anesthesia, the assigned loading dose of dexmedetomidine was infused intravenously for 10 minutes, after which infusion was maintained at a rate of 0.3 µg/kg/h for the next 10 minutes in all groups. We assessed the depth of sedation with the Ramsay sedation scale every five minutes and measured vital signs and the oxygen saturation. The ED50 and ED95 of dexmedetomidine to obtain adequate sedation (Ramsay sedation score ≥ 3) upon the completion of the loading dose were calculated with logistic regression. Results The ED50 and ED95 of dexmedetomidine for adequate sedation were 0.29 µg/kg (95% confidence intervals [CI] 0.14-0.44) and 0.86 µg/kg (95% CI 0.52-1.20), respectively. Hypotension was frequent in groups IV, V compared to groups I, II, III (31.6 vs. 3.6%, P = 0.013). Conclusions ED95 of dexmedetomidine loading dose for adequate sedation is 0.86 µg/kg. However, dose higher than 0.5 µg/kg can lead to hemodynamic instability.

Background Hip fracture surgery on elderly patients is associated with a high incidence of morbidity and mortality. The aim of this study is to identify the risk factors related to the postoperative mortality and complications following hip fracture surgery on elderly patients. Methods In this retrospective study, the medical records of elderly patients (aged 65 years or older) who underwent hip fracture surgery from January 2011 to June 2014 were reviewed. A total of 464 patients were involved. Demographic data of the patients, American Society of Anesthesiologists physical status, preoperative comorbidities, type and duration of anesthesia and type of surgery were collected. Factors related to postoperative mortality and complications; as well as to intensive care unit admission were analyzed using logistic regression. Results The incidence of postoperative mortality, cardiovascular complications, respiratory complications and intensive care unit (ICU) admission were 1.7, 4.7, 19.6 and 7.1%, respectively. Postoperative mortality was associated with preoperative respiratory comorbidities, postoperative cardiovascular complications (P < 0.05). Postoperative cardiovascular complications were related to frequent intraoperative hypotension (P

To avoid the occurrence of fatal complications of blood transfusion, several tests are implemented before transfusion. The tests include ABO typing, Rh typing, cross-matching test and blood antibody screening test, and in usual they are completed before transfusion. However in the case of repetitive operations done via brief distance, reexamination for blood antibody tends to be omitted. After 2 previous operations, 30 years old male patient showed positive blood antibody screening during the third operation. Although antibody screening test performed before the first operation, no unexpected blood antibody was detected. During the third operation, after the decision to start transfusion was made, it took two hours to find appropriate blood. There was no significant deterioration of patient's condition but the loss of time could lead to critical consequences. We present this case to make anesthesiologists and surgeons aware of possibility of unexpected blood antibody detection after transfusion.

Background 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists are effective and safe on postoperative nausea and vomiting (PONV). Palonosetron, the newest 5-HT3 antagonist, has potent antiemetic property. We hypothesized that a combination of palonosetron and dexamethasone could more decrease PONV than palonosetron alone. Methods Among the patients scheduled to undergo laparoscopic gynecologic surgery, mastoidectomy with tympanoplasty or thyroidectomy under general anesthesia, eighty four female patients with at least two PONV risk factors were enrolled in this study. They were received randomly 0.075 mg palonosetron and 4 mg dexamethasone (group C) or 0.075 mg palonosetron alone (group P). The severity of PONV using Rhodes index and the percentage of complete response during postoperative 24 hours were compared between groups. Results The frequency of mild/moderate/great/severe PONV based on Rhodes index were 9.8%/0%/0%/0% and 9.3%/2.3%/2.3%/0% in group P and group C, respectively. Complete response for PONV was observed in 90.2% and 86% of patients in group P and group C, respectively. The overall incidence of PONV in group P and C was 9.8% and 14%, respectively. There was no significant difference between the two groups. Conclusions There were no differences between palonosetron monotherapy and combination therapy of palonosetron and dexamethasone in patients with high emetogenic risk.

Ehlers-Danlos syndrome (EDS) is a rare inherited disorder of the connective tissue that is characterized by hyperextensible skin, hypermobile joints and abnormalities of the cardiovascular system. A 15-year-old girl with Ehlers-Danlos syndrome underwent thoracolumbar surgery for deformity correction. After surgery, an abdominal aortic rupture occurred, and she complained of abdominal distension had an abdominal circumference of 80 cm. Abdominal computed tomography revealed a pseudoaneurysm and a large hematoma at the retroperitoneum. She died of a massive hemorrhage during subsequent abdominal aortic surgery.

A tourniquet is used frequently in orthopedic surgeries, including total knee replacement, to reduce bleeding and enhance the visual field during surgery. Herein, we present a case with massive bleeding that occurred during a total knee replacement that had administered a tourniquet with adequate pressure. A 65-year-old man presented to the orthopaedic clinic for right total knee replacement due to osteoarthritis. The patient had right lower limb artery obstruction and a history of a right femoro-popliteal artery bypass graft 7 years prior to his visit. He was 169 cm tall weighing 68 kg. The patient had no other specific medical history, and no abnormal finding was covered on the preoperative examination. When the patient arrived at the operating room, his blood pressure was 150/90 mmHg. We provided propofol 120 mg and rocuronium 50 mg followed by induction with sevoflurane and 1 : 1 of oxygen and N2O. An inflation tourniquet with a pressure of 300 mmHg was applied to the right thigh. While the surgeon was making the skin incision to expose the joint, unpredicted massive bleeding occurred. Just before the tourniquet was applied, the patient's blood pressure was 95/65 mmHg, and right after the tourniquet was inflated, it was 130/80 mmHg. Based on the assumption of a tourniquet function error, we applied a new tourniquet with 300 mmHg of pressure on the right thigh. However, the bleeding continued even when we the raised pressure up to 400 mmHg. The bleeding decreased considerably when we deflated the cuff. Furthermore, with ultrasonographic guidance, we found that the femoral artery flow was not blocked by the tourniquet; therefore, the surgeon proceeded with the surgery without use of a tourniquet. During the surgery, 1,200 ml of crystalloid solution, 500 ml of colloid solution and packed RBC 4 units were administered and the estimated blood loss was 2,500 ml. Upon searching for the cause of the unpredicted bleeding, we examined the blood flow of the right femoro-popliteal artery bypass graft with ultrasonography 6 months later. It showed that both the femoro-popliteal artery bypass graft with or without 350 mmHg of tourniquet pressure had good blood flow (Fig. 1). A tourniquet is frequently used in total knee joint replacement surgeries to block the vascular flow of the limb during surgery. However, complications such as thigh pain, nerve injury, compartment syndrome, and nonalignment of the patella as well as systemic complications such as deep venous thrombosis, hypertension, and arrhythmia may occur. Therefore, it is important to maintain an adequate pressure and duration while using a tourniquet. There is no absolute limit on the pressure and duration when using a tourniquet, but Flatt [1] reported 2 hours is an adequate time if the patient has no hemodynamic problems. Horlocker et al. [2] reported 300 mmHg for the tourniquet pressure as being adequate for the lower limb. In this case, bleeding continued with an initial tourniquet pressure of 300 mmHg and even continued after we applied 400 mmHg of pressure. The use of the tourniquet instead increased the blood flow in our case. It is believed that the use of the tourniquet was unable to block the graft artery flow but collapsed the venous flow, which resulted in the increased blood loss. In case of artery occlusion above the knee, a polytetrafluroethylene (PTFE) bypass graft is used in elderly when an artery is in poor condition or there is no venous graft. For a PTFE bypass graft, it has good short outcomes compared to the use of a venous graft. For long term outcomes, a PTFE bypass graft shows less patency though. This case also used a PTFE bypass graft and this may have affected the blood flow when compared with a venous graft. However, there is no report on this issue yet. Complications from femoro-popliteal bypass grafts are myocardial ischemia, cerebral infarct, infection on the graft site, peripheral venous thrombosis, and sexual dysfunction by autonomic nerve injury. Infection on the graft site may result in permanent adhesion or fibrosis [3]. Therefore, in our case, it is believed that the patient had an asymptomatic infection, which resulted in adhesion and fibrosis around the artificial vessel graft. The adhesion and fibrosis blocked vessel collapsed even under high pressure causing severe bleeding afterwards. There is controversy about the use of a tourniquet in patients with peripheral artery occlusion. Some say it is safe not to use a tourniquet [4]. Others say there is no difference in postoperative vascular complications by using a tourniquet [5]. Therefore, adequate discussion must be carried out with orthopedists before use of a tourniquet. Patients with a history of a femoro-popliteal bypass graft should be evaluated first with ultrasonography on whether vascular flow can be blocked with a tourniquet. If it is decided that a tourniquet should not be used during surgery, care should be taken for the bleeding during surgery and for postoperative vascular complications.

Transverse myelitis is an inflammatory or demyelinating disease of the spinal cord, which causes bilateral hypoesthesia and motor weakness, a decrease in deep tendon reflex spasticity of the extremities, and urination and defecation problems in the areas lower than affected spinal segment, without any observation of spinal cord injury, spinal lesion, or tumor, and no observation of pressure on the spinal cord [1]. We report our experience of transverse myelitis that occurred after spinal-epidural combined anesthesia for caesarian section with a literature review. A 37-year-old pregnant woman (height 162 cm, weight 72 kg) with no specific medical history and no abnormalities was performed spinal-epidural combined anesthesia in the L 3-4 epidural space with intrathecal administration of 5% bupivacaine 7 mg for caesarean delivery at 39 + 1 weeks. Vital signs were stable with no specific event during this procedure and surgery. Fifteen minutes before the end of the surgery, fentanyl 50 µg and 1% lidocaine 40 mg were injected into the epidural space with N/S 2 ml for post-operative analgesia. For patient controlled analgesia, fentanyl 350 µg + 0.5% chirocaine 50 mg + N/S 83 ml were combined and connected to the epidural catheter with the following settings: basal rate 2 ml/hr, bolus 1 ml/hr, and lockout time 30 min. Thirty minutes after transported into the recovery room, the anesthesia was up to T12, and the patient was moved to a general ward after confirmation of stable vital signs. Two days after surgery, the epidural catheter was removed. But the patient continuously complained of hypoesthesia and motor weakness in the left lower extremities. The condition gradually worsened to both sides so a lumbar and thoracic MRI was performed, but no abnormalities were found. Four days after surgery, WBC count was 30 cell/mm3 and protein was 91 mg/dl in the cerebrospinal fluid examination. Except that, abnormal finding was not seen. The patient was IV injected with methylprednisolone 1,000 mg as a steroid pulse therapy for 5 days for suspicion of transverse myelitis. Five days after surgery, in the somatosensory evoked potential examination, bilateral peripheral conduction disturbance was observed in the posterior tibial nerve. The lumbar magnetic resonance imaging performed 7 days after surgery was normal like before, and brain MRI was normal. Ten days after surgery, motor power of lower extremities slightly increased. Thus, mobility was recovered and prednisolone 40 mg was orally administered from that day. Twenty-two days after surgery, an electrophysiology test's results showed radiculopathy in the L3-S1 region on both sides. Steroid therapy was stopped and walking practice was performed along with physical therapy. Six months after surgery, the right side displayed nearly normal motor function. The left side showed grade III hip joint flexion and grade IV extension, grade IV knee joint flexion and extension, and grade II ankle joint dorsiflexion and grade III extension. Approximately 7 months after the surgery, the patient was discharged. The prevalence of transverse myelitis is 4.6 per million in the United States, and mostly develops in young adults and middle-aged people regardless sex. Most of this disease is idiopathic but it can accompany vascular malformation or autoimmune disease such as multiple sclerosis, systemic lupus erythematosis. Also myelitis symptoms developed from preceding virus infections such as Ebstein-Barr virus, cytomegalovirus was reported. As seen in our case, transverse myelitis can develop in spinal anesthesia. Paresthesia from spinal cord injury can occur not only from needle insertion, but also from the toxicity of the regional anesthesia, secondary irritation and edema from injection, hematoma, occlusion of spinal cord artery, and a state of hypoperfusion [2]. Contrary to the case reported by Teh et al. [3] where patient's recovery time was within 24 hours, our case had a very long recovery period. Since the regional anesthesia used was not a high dose, it is unreasonable to contend that the patient developed regional anesthesia induced transverse myelitis. Also Jha and Kumar [4] reported transverse myelitis occurred after the patient experienced pain like severe electric shock when inserting the needle during spinal anesthesia. However our patient did not complain of pain and no observations of pressure such as a hematoma was found in the MRI. When spinal anesthesia is performed on patients in sedation state they become insensitive to pain, and paresthesia can be developed from spinal cord damage. However, the patient in our case did not receive any sedatives or analgesics before and during spinal anesthesia so this possibility is low. Nevertheless, it cannot be ruled out that the patient had insufficient information about spinal anesthesia and ignored any pain she felt. Approximately half of the patients with transverse myelitis complain of pain; however, there could be cases like ours where the patient only complains of muscle weakness and hypoesthesia without pain. Chronic neuropathic pain can also occur in some patients. The prognosis is known to be relatively good, but in severe cases, permanent physical disabilities can remain or even lead to death. Steroid IV injection is used as the primary treatment for acute central nervous system demyelinating disease, and antidepressants, anticonvulsants, analgesics, etc. are used too. When such medical treatment is ineffective, interventions such as nerve blocks can be attempted but the effects are insignificant. Although the physiological mechanism is not clear, there are reports that show spinal cord stimulation has been effective in treating pain. Most of the causes of transverse myelitis are idiopathic and it can occur without evidence of hematoma or infection after combined spinal-epidural anesthesia as in our case.

Pheochromocytoma is a catecholamine-secreting tumor. Reduction of the high risk of intraoperative hypertension during tumor manipulation requires adequate preoperative preparation. Even though adequate pretreatment is performed, uncontrolled hemodynamic responses during the surgery may result in postoperative complications. In particular, undiagnosed pheochromocytoma without any pretreatment can lead to highly severe life-threatening hypertensive crisis [1]. Therefore, it has always posed a great challenge for anesthesiologists [2]. In the case of our patient, induction of spinal anesthesia helped in the prevention of severe hypertension and, consequently, the development of severe complications.

Background: Reduction of nasal bone fracture can be performed under general or local anesthesia. The aim of this study was to compare general anesthesia (GA) and monitored anesthetic care (MAC) with dexmedetomidine based on intraoperative vital signs, comfort of patients, surgeons and nurses and the adverse effects after closed reduction of nasal bone fractures. Methods: Sixty patients with American Society of Anesthesiologists physical status I or II were divided into a GA group (n = 30) or MAC group (n = 30). Standard monitorings were applied. In the GA group, general anesthesia was carried out with propofol-sevoflurane-N 2O. In the MAC group, dexmedetomidine and local anesthetics were administered for sedation and analgesia. Intraoperative vital signs, postoperative pain scores by visual analog scale and postoperative nausea and vomiting (PONV) were compared between the groups. Results: Intraoperatively, systolic blood pressures were significantly higher, and heart rates were lower in the MAC group compared to the GA group. There were no differences between the groups in the patient, nurse and surgeon’s satisfaction, postoperative pain scores and incidence of PONV. Conclusions: MAC with dexmedetomidine resulted in comparable satisfaction in the patients, nurses and surgeons compared to general anesthesia. The incidence of postoperative adverse effects and severity of postoperative pain were also similar between the two groups. Therefore, both anesthetic techniques can be used during the reduction of nasal bone fractures based on a patient’s preference and medical condition. (Korean J Anesthesiol 2013; 65: 209-214)

Background: Ulinastatin is a glycoprotein derived from human urine and a serine protease inhibitor found in human urine and blood. Ulinastatin increases both liver blood flow and urine output. Rocuronium is eliminated mainly through the liver and partly through the kidney, hepatic elimination of rocuronium might be enhanced by ulinastatin. We examined the effect of ulinastatin on the neuromuscular block caused by rocuronium. Methods: Forty four adult patients were randomly divided into two groups of 22 patients each, i.e. the study group and the control group. In the study group, a bolus dose of ulinastatin 5,000 U/kg was administered 2 min before the injection of rocuronium 0.6 mg/kg. In the control group, normal saline was administered instead of ulinastatin. For the monitoring of both onset and recovery from neuromuscular blockade, train­of­four (TOF) and post­tetanic count were used with TOF­Watch Sx. All patients underwent general anesthesia with total intravenous anesthesia (TIVA) of remifentanil and propofol, using the effect site target infusion system. Results: In the study group, the onset of neuromuscular block was significantly slower than in the control group (P < 0.05). The recovery time from the rocuronium injection to the return of PTC was also significantly shorter in the study group than in the control group (P < 0.05). Similarly, times to the return of T1, T2, T3, and T4 (i.e. the first, second, third, and fourth response of TOF) were significantly shorter in the study group than in the control group (P < 0.05). Conclusions: Ulinastatin significantly delays the onset of neuromuscular block and accelerates the recovery from the block caused by rocuronium. (Korean J Anesthesiol 2012; 62: 240­244)

Massive pulmonary embolism is associated with significant perioperative morbidity and mortality. We report here on a case of a 69-year-old man who suffered a massive pulmonary embolism with pulseless electrical activity during knee arthroscopic surgery. After a diagnosis was made by performing transthoracic echocardiography, the patient was treated with recombinant tissue-type plasminogen activator. The patient was transferred to the intensive care unit after his hemodynamic status improved. The patient went on to make a full cardiopulmonary recovery without any complications.

Tracheomalacia is a malformation of the tracheal membranosa. It is maintained during spontaneous breathing but can be altered by bronchoscopy or positive airway pressure. Tracheomalacia is associated with a high mortality and may cause prolonged intubation and ventilation. Here, the case of a 13-day-old infant with jejunoileal stenosis that had surgery is reported. During induction of general anesthesia, endotracheal intubation was attempted several times with different sized endotracheal tubes. Airway obstruction occurred after the endotracheal intubation. After the airway was maintained, the operation was completed. Tracheomalacia was diagnosed after otolaryngology evaluation postoperatively.

In thoracic anesthesia with one lung ventilation (OLV), end-tidal CO2 (PeTCO2) monitoring may not be accurate to estimate PaCO2 mainly due to ventilation/perfusion mismatching.This study aimed to asses the clinical usefulness and accuracy of a transcutaneous CO2 (PtCCO2) monitoring in thoracic anesthesia, compared with PeTCO2. Methods:18 patients of ASA physical status 1 or 2, required a long period of OLV were researched.The lungs were mechanically ventilated in the lateral decubitus position.We measured PaCO2, PeTCO2, PtCCO2 during two lung ventilation (TLV) and 15 min, 30 min, 60 min after OLV.For comparing the differences of PtCCO2/PaCO2 and PtCCO2/PaCO2, we figured out bias (mean difference between values) and precision (standard deviation of bias) by using Bland-Altman plot.We compared the differences of each value, PeTCO2/PaCO2, PtCCO2/PaCO2, using the student`s t-test. Results:The bias ± precision of PeTCO2/PaCO2 and PtCCO2/PaCO2 was each 7.82 mmHg ± 3.98 mmHg, 1.95 mmHg ± 2.66 mmHg during TLV and that of mean value of PeTCO2/PaCO2 and PtCCO2/PaCO2 was each 6.93 mmHg ± 2.6 mmHg, 2.35 mmHg ± 1.66 mmHg during OLV.PtCCO2/PaCO2 differences were significantly less than PeTCO2/PaCO2 differences (P ＜ 0.05). Conclusions:During one lung ventilation, PtCCO2 monitoring is more useful and accurate than PeTCO2 monitoring for assessing PaCO2 levels.

Kyphoscoliosis is a deformity of the costovertebral skeletal structures characterized by an anterior flexion (kyphosis) and lateral curvature (scoliosis) of the patient’s vertebral column.1) In kyphoscoliosis, lung volume and compliance is reduced due to the change of vertebral column. The work of breathing is increased by abnormal mechanism of the thorax and by increased airway resistance resulting from small lung volume. Airway management and respiratory problems are common and spinal deformities can cause difficulties with regional anesthesia. We had experienced a successful spinal anesthesia for closed reduction and internal fixation (CRIF) and proximal femoral nail (PFN) of fractured intertrochanteric femur in a patient with extremely severe thoracolumbar kyphoscoliosis.

A 76-year-old woman presented with tracheal stenosis caused by a thyroid mass. Her symptoms included dyspnea and wheezing. Cervical computed tomography scans revealed an 8.5 × 7.8 cm sized mass and a trachea with an internal lumen 4.3 mm in diameter. The mass caused marked stenosis and deviation of the airway. H owever, it was not clear if the tracheal lumen was invaded by the mass. We predicted that airway management would be problematic, even in the absence of invasion. Options for intubation included small sized endotracheal tube, fiberoptic bronchoscopy-guided intubation, high frequency jet ventilation, and percutaneous cardiopulmonary support (PCPS). We decided to use PCPS to reduce the chance of ineffective oxygenation and related complications. After supplementing PCPS with epidural anesthesia, general anesthesia was performed without complications. The patient underwent surgical removal of the mass. PCPS was discontinued on the day of surgery, and after two weeks of uncomplicated mechanical ventilatory support, the patient was discharged home. (Korean J Anesthesiol 2008; 54: 703～7)

Background: Tracheal intubation induces clinically adverse hemodynamic changes. Various pharmacological strategies for controlling these reponses have been suggested with opioids being widely used. The purpose of this study was to determine the effect site concentration of remifentanil in blunting the cardiovascular responses to tracheal intubation according to gender. Methods: Eighty ASA physical status I or II patients, aged 20－40 years undergoing elective surgery, were classified into a male group (n = 40) and a female group (n = 40). Anesthesia was induced using a propofol target controlled infusion (TCI: Marsh model). A propofol target effect-site concentration of 4μg/ml was chosen. Rocuronium 0.6 mg/kg was administered after the patients lost consciousness. Remifentanil TCI (Minto model) was started 1 min after the propofol injection. Initially, an effect-site concentration of 3 ng/ml was chosen. The next concentration was chosen using the up-and-down method reported by Dixon. The non-invasive blood pressure and heart rate were recorded before induction (baseline), after the remifentanil injection, immediately after intubation as well as 1 and, 3 minutes after intubation. Results: Probit analysis revealed a remifentanil effect-site EC50 and EC95 in the male group to be 1.94 ng/ml (95% CI, 1.60－2.27 ng/ml ), 3.07 ng/ml (95% CI, 2.65－4.06 ng/ml), respectively. The EC50 and EC95 in the female group were 1.69 ng/ml (95% CI, 1.35－2.01 ng/ml), 2.81 ng/ml (95% CI, 2.39－3.81 ng/ml), respectively. There were no significant differences between the two groups. Conclusions: The effect-site concentration of remifentanil blunting the cardiovascular responses to tracheal intubation during propofol TCI anesthesia was between 2 and 3 ng/ml. There were no gender differences.