Bone regeneration of demineralized dentin matrix with platelet-rich fibrin and recombinant human bone morphogenetic protein-2 on the bone defects in rabbit calvaria / 대한악안면성형재건외과학회지

Background@#This study was to evaluate the bone formation ability of demineralized dentin matrix (DDM) combined with platelet-rich fibrinogen (PRF) and DDM combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) to improve the osteoinductive ability of DDM. @*Methods@#After four bone defects with a diameter of 8mm were created in the calvarium of each rabbit, DDM was grafted into the first defect (experimental groups 1), a combination of DDM and PRF was grafted into the second defect (experimental groups 2), and DDM with absorbed rhBMP-2 was grafted into the third defect (experimental groups 3). The fourth defect was used as the control group. Twelve healthy male rabbits (New Zealand, white rabbits) weighing around 3.0–4.0 kg were used. Among 12 rabbits, 3 rabbits were sacrificed immediately after surgery and at 2, 4, and 8 weeks after surgery, respectively. Histopathologic analysis and histomorphometric analysis were conducted to evaluate bone formation in each group. @*Results@#The PRF/DDM group did not show a significantly higher degree of new bone formation in calvarial bone defects than the DDM group at 2, 4, and 8 weeks postoperatively in histopathological findings and histomorphometric results. On the other side, the rhBMP-2/DDM group showed higher degrees of new bone formation and calcification, and the lamellae of bone matrix, which are observed in mature bone tissue, were more distinctly visible in the rhBMP-2/DDM group. Moreover, the rhBMP-2/DDM group showed a significantly higher amount of new bone formation, compared to the DDM group at 4 and 8 weeks postoperatively (P<0.05) in histomorphometric results. @*Conclusion@#The DDM has great potential as a carrier for the maintenance and sustained release of rhBMP-2, which has been recently receiving wide attention as a type of signaling molecules to promote bone formation.

Laryngeal granulomas in patients after two-jaw surgery: Four cases report

BACKGROUND: Endotracheal intubation can cause focal ischemia, damage or edema to the laryngeal mucosa, and may be followed by serious complications such as vocal cord paralysis, ulcers, and granulation tissue formation. Laryngeal granuloma is rare but also a significant late complication of endotracheal intubation, and anesthesiologists should be concerned about it.CASE: We experienced four cases of laryngeal granuloma that developed after two-jaw surgery January 2017–December 2018 in our hospital and would like to report these cases with brief review of literature.CONCLUSIONS: There are frequent movements on the head and neck in maxillofacial surgery and the nasotracheal intubation should be prolonged after bimaxillary osteotomy surgery because of post-operative airway problems. This may be why two-jaw surgery may have higher occurrence of laryngeal granuloma than others.

Fiberoptic bronchoscope and C-MAC video laryngoscope assisted nasal-oral tube exchange: two case reports

In cases of multiple facial trauma and other specific cases, the anesthesiologist may be asked to convert an oral endotracheal tube to a nasal endotracheal tube or vice versa. Conventionally, the patient is simply extubated and the endotracheal tube is re-inserted along either the oral or nasal route. However, the task of airway management can become difficult due to surgical trauma or worsening of the airway condition. Fiberoptic bronchoscopy was considered a novel method of airway conversion but this method is not useful when there are secretions and bleeding in the airway, or if the anesthesiologist is inexperienced in using this device. We report a successful airway conversion under the aid of both, a fiberoptic bronchoscope and a C-MAC video laryngoscope.

Histologic study of bone-forming capacity on polydeoxyribonucleotide combined with demineralized dentin matrix / 대한악안면성형재건외과학회지

BACKGROUND: This study examined the osteoinductive activity of demineralized dentin matrix (DDM) from human and polydeoxyribonucleotide (PDRN) for nude mice. METHODS: Twenty healthy nude mice, weighing about 15~20 g, were used for the study. DDM from human and PDRN were prepared and implanted subcutaneously into the dorsal portion of the nude mice. The nude mice were sacrificed at 1, 2, and 4 weeks after grafting and evaluated histologically by hematoxylin-eosin and Masson's trichrome staining. The specimens were also evaluated via a histomorphometric study. RESULTS: The DDM and PDRN induced new bone, osteoblasts, and fibroblasts in soft tissues. The histological findings showed bone-forming cells like osteoblasts and fibroblasts at 1, 2, and 4 weeks. New bone formation was observed in the histomorphometric study. In particular, the ratio of new bone formation was the highest at 2 weeks compared with the first week and fourth week. CONCLUSIONS: In this study, we showed that the PDRN used in this experimental model was able to induce bone regeneration when combined to the DDM.

Posterior reversible encephalopathy syndrome after normal vaginal delivery: A case report

Benign primary headaches are common during the postpartum period. However, there are several other kinds of headaches caused by specific underlying pathologies like post-dural puncture headache (PDPH), pregnancy induced hypertension, cortical vein thrombosis, posterior reversible encephalopathy syndrome (PRES), subarachnoid hemorrhage, intracranial hemorrhage, brain tumor, and so on. These headaches are rare but each can be life threatening conditions when diagnosis is delayed. If a patient was treated for another type of headache, like a PDPH, the diagnosis would be even more difficult. We report on the case of a 24 year-old woman who suffered with PDPH followed by postpartum eclampsia with PRES.

Effect on bone formation of the autogenous tooth graft in the treatment of peri-implant vertical bone defects in the minip / 대한악안면성형재건외과학회지

BACKGROUND: The aim of this study was to evaluate the effect of autogenous tooth bone as a graft material for regeneration of bone in vertical bony defects of the minipigs. MATERIAL AND METHODS: Six minipigs were used in this study. Four molars were extracted in the right mandibular dentition and sent to the Korea Tooth Bank for fabrication of autogenous tooth bone. Ten days later, each extraction site was implanted with MS Implant Narrow Ridge 3.0 x 10mm fixture (Osstem, Seoul, Korea) after standardized 2mm-sized artificial vertical bony defect formation. Pineappleshaped Root-On type autogenous tooth bones were applied to the vertical defects around the neck area of the posterior three fixtures and the fore-most one was not applied with autogenous bone as a control group. Each minipig was sacrificed at 4, 8, 12 weeks after fixture installation and examined radiologically and histologically. Histological evaluation was done under light microscope with Villanueva osteochrome bone staining with semi-quantitative histomorphometric study. Percentage of new bone over total area (NBF) and bone to implant contact (BIC) ratio were evaluated using digital software for area calculation. RESULT: NBF were 48.15 +/- 18.02%, 45.50 +/- 28.37%, and 77.13 +/- 15.30% in 4, 8, and 12 weeks, respectively for experimental groups. The control group showed 37.00 +/- 11.53%, 32.25 +/- 26.99%, and 1.33 +/- 2.31% in 4,8,12 weeks, respectively. BIC ratio were 53.08 +/- 19.82%, 45.00 +/- 28.37%, and 75.13 +/- 16.55% in 4,8,12 weeks, respectively. Those for the control groups were 38.33 +/- 6.43%, 33.50 +/- 29.51 %, and 1.33 +/- 2.31% in 4, 8, 12 weeks, respectively. CONCLUSION: Autogenous tooth bone showed higher score than control group in NBF and BIC in all the data encompassing 4,8,12 weeks specimens, but statistically significant only 12 weeks data in both NBF and BIC.

Expression of vascular endothelial growth factor in oral squamous cell carcinoma

OBJECTIVES: The goal of this study was to determine the correlation of clinicopathological factors and the up-regulation of vascular endothelial growth factor (VEGF) expression in oral squamous cell carcinoma. MATERIALS AND METHODS: Immunohistochemical staining of VEGF and quantitative real-time polymerase chain reaction (RT-PCR) of VEGF mRNA were performed in 20 specimens from 20 patients with oral squamous cell carcinoma and another 20 specimens from 20 patients with carcinoma in situ as a controlled group. RESULTS: The results were as follows: 1) In immunohistochemical study of poorly differentiated and invasive oral squamous cell carcinoma, high-level staining of VEGF was observed. Significant correlation was observed between immunohistochemical VEGF expression and histologic differentiation, tumor size of specimens (Pearson correlation analysis, significance r>0.6, P<0.05). 2) In VEGF quantitative RT-PCR analysis, progressive cancer showed more VEGF expression than carcinoma in situ. Paired-samples analysis determined the difference of VEGF mRNA expression level between cancer tissue and carcinoma in situ tissue, between T1 and T2-4 (Student's t-test, P<0.05). CONCLUSION: These findings suggest that up-regulation of VEGF may play a role in the angiogenesis and progression of oral squamous cell carcinoma.

Epidural hematoma after thoracic epidural analgesia in a patient treated with ketorolac, mefenamic acid, and naftazone: a case report / 대한마취과학회지

A 26-year-old male undergoing thoracotomy and bleeding control received a preoperative thoracic epidural for postoperative analgesia. On the fifth postoperative day, paralysis of both lower limbs occurred and urgent magnetic resonance imaging showed massive anterior epidural hematoma. During laminectomy and decompression, platelet dysfunction was diagnosed and preoperative non-steroidal anti-inflammatory drugs medications were supposed to the cause of platelet dysfunction. After infusion of ten units of platelet concentrate, coagulopathy was improved. We should be more careful to drugs with antiplatelet effect when using regional analgesia.

Effectiveness of milrinone for cardiogenic shock due to massive pulmonary aspiration: a case report / 대한마취과학회지

Pulmonary aspiration of gastric contents is one of the most frightening complications during anesthesia. Although pulmonary aspiration of gastric contents in general surgical patients is not common and resulting long-term morbidity and mortality are rare, severe hypoxemia and other sequelae of pulmonary aspiration continue to be reported. We report a case of massive aspiration of gastric contents during induction of general anesthesia, resulting in cardiac arrest due to severe pulmonary hypertension and myocardial infarction. Sustained cardiac arrest and shock that did not respond the conventional resuscitation was successfully treated using milrinone. The patient was discharged without complications in 20 days.

Comparison of ultrasound-guided supraclavicular block according to the various volumes of local anesthetic / 대한마취과학회지

BACKGROUND: The ultrasound guidance in regional nerve blocks has recently been introduced and gaining popularity. Ultrasound-guided supraclavicular block has many advantages including the higher success rate, faster onset time, and fewer complications. The aim of this study was to examine the clinical data according to the varied volume of local anesthetics in the ultrasound-guided supraclavicular block. METHODS: One hundred twenty patients were randomized into four groups, according to the local anesthetic volume used: Group 35 (n = 30), Group 30 (n = 30), Group 25 (n = 30), and Group 20 (n = 30). Supraclavicular blocks were performed with 1% mepivacaine 35 ml, 30 ml, 25 ml, and 20 ml, respectively. The success rate, onset time, and complications were checked and evaluated. RESULTS: The success rate (66.7%) was lower in Group 20 than that of Group 35 (96.7%) (P < 0.05). The average onset times of Group 35, Group 30, Group 25, and Group 20 were 14.3 +/- 6.9 min, 13.6 +/- 4.5 min, 16.7 +/- 4.6 min, and 16.5 +/- 3.7 min, respectively. There were no significant differences. Horner's syndrome was higher in Group 35 (P < 0.05). CONCLUSIONS: In conclusion, we achieved 90% success rate with 30 ml of 1% mepivacaine. Therefore, we suggest 30 ml of local anesthetic volume for ultrasound-guided supraclavicular block.

A suspected case of malignant hyperthermia that was successfully treated with dantrolene administration via nasogastric tube / 대한마취과학회지

No abstract available.

Students' Response to the Questionnaire about the Usefulness of Concept Maps for Problem-Based Learning and the Forms of Concept Maps / 한국의학교육

PURPOSE: Concept maps have been studied and used in diverse ways in scientific fields. This study aimed to investigate the usefulness and limitations of using concept maps during problem-based learning (PBL) in Year 3 medical students. METHODS: After each PBL module, we gathered concept maps from each pair of students and questionnaires about the usefulness and limitations of concept maps, and analyzed them. RESULTS: There were two types of concept maps, with some modifications. The students felt that concept maps provided overall understanding, analysis, and reorganization of problem cases. But, they also criticized shortage of disciplines related to drawing skills and rationales for each type of map. A strong need for expert maps and feedback for students resulted. CONCLUSION: For optimal use of concept maps, we recommend that the committee implements a plan to teach drawing skills, explains rationales for each type of map, and gives feedback to students.

Percutaneous Cardiopulmonary Support (PCPS) for Patients with Cardiopulmonary Bypass Weaning Failure during Open Heart Surgery / 대한흉부외과학회지

BACKGROUND: Recently, percutaneous cardiopulmonary support (PCPS) has been widely used to rescue patients in cardiogenic shock or cardiac arrest. However, patients with cardiopulmonary bypass (CPB) weaning failure during open heart surgery still have very poor outcomes after PCPS. We investigated clinical results and prognostic factors for patients who underwent PCPS during open heart surgery. MATERIAL AND METHOD: From January 2005 to December 2008, 10 patients with CPB weaning failure during open heart surgery underwent PCPS using the CAPIOX emergency bypass system (EBS(R), Terumo Inc, Tokyo, Japan). We retrospectively reviewed the medical records of those 10 patients. RESULT: The average age of the patients was 60.2+/-16.5 years (range, 19~77 years). The mean supporting time was 48.7+/-64.7 hours (range, 4~210 hours). Of the 10 patients, 6 (60%) were successfully weaned from the PCPS While 5 (50%) were able to be discharged from the hospital. Complications were noted in 5 patients (50%). In univariate analysis, long aortic cross clamp time during surgery, mediastinal bleeding during PCPS and high level of Troponin-I before PCPS were significant risk factors. All of the discharged patients are still surviving 34+/-8.6 months (range, 23~48 months) post-operatively. CONCLUSION: The use of PCPS for CPB weaning failure during open heart surgery can improve the prognosis. More experience and additional clinical studies are necessary to improve survival and decrease complications.

Intracerebral hemorrhage in a patient with preeclampsia and HELLP syndrome which was diagnosed after caesarean section : A case report / 대한마취과학회지

Intracerebral hemorrhage (ICH) is one of very dangerous complications of preeclampsia/eclampsia. We experienced postoperative ICH in a 39-year-old woman with preeclampsia and HELLP syndrome. The paturient complained severe headache and upper abdominal pain with nausea and vomiting. Her initial blood pressure was 190/120 mmHg and her heart rate was 80 beat/min. The diagnosis of preeclampsia with HELLP syndrome was confirmed by the severe hypertension and the laboratory findings. She was drowsy at the emergency room but she lost consciousness when transferring to the operation room. Caesarean section was done under general anesthesia. After the operation she could not recover self-respiration and consciousness. Her brain CT showed ICH in the basal ganglia with intraventricular hemorrhage and severe brain edema. She expired one the 5 th post operative day due to brain death and multiple organ failure. Early diagnosis is the key to treating ICH.

Surgical Treatment of Patients with Abdominal Aortic Aneurysm / 대한흉부외과학회지

BACKGROUND: Open surgical repair of abdominal aortic aneurysms was initiated by Dubost in 1952. Despite the rapid expansion of percutaneous endovascular repair, open surgical repair is still recognized for curative intent. We retrospectively analyzed surgical outcome, complications, and mortality-related factors for patients with abdominal aortic aneurysms over a 6 year period. MATERIAL AND METHOD: We analyzed 18 patients who underwent surgery for abdominal aortic aneurysms between March 2002 and March 2008. The indications for surgery were rupture, a maximal aortic diameter >60 mm, medically intractable hypertension, or pain. RESULT: The mean age was 66.6+/-9.3 years (range, 49~81 years). Twelve patients (66.7%) were males and 6 patients were females. Extension of the aneurysm superior to the renal artery existed in 6 patients (33.3%), and extension to the iliac artery existed in 13 patients (72.2%). Five patients (27.8%) had ruptured aortic aneurysms. The mean maximal diameter of the aorta was 72.2+/-12.9 mm (range, 58~109 mm). Surgery was performed by a midline laparotomy, and 6 patients underwent emergency surgery. The mean total ischemic time from aorta clamping to revascularization was 82+/-42 minutes (range, 35~180 minutes). The mortality rate was 16.7%; the mortality rate for patients with ruptured aneurysms was 60%, and the mortality rate for patients with unruptured aneurysms was 0%. The postoperative complications included one each of renal failure, femoral artery and vein occlusion, and wound infection. The patients who were discharged had a long-term survival of 34+/-26 months (range, 4~90 months). Rupture and emergency surgery had a statistically significant mortality-related factor (p<0.05). CONCLUSION: Emergency surgery for ruptured aortic aneurysms continues to have a high mortality, but unruptured cases are repaired with relative safety. Successfully operated patients had long-term survival. Even though endovascular aortic repair is the trend for abdominal aortic aneurysms, aggressive application should be determined with care. Experience and systemic support of each center is important in the treatment plan

Dyspnea after supraclavicular brachial plexus block in a morbidly obese patient due to phrenic nerve block: A case report / 대한마취과학회지

A 57-year-old woman with morbid obesity (BMI: 37.39) was scheduled for ligament reconstruction with tendon interposition of the carpometacarpal joint. A difficult supraclavicular brachial plexus block was performed using a 22-gauge regional block needle with a nerve stimulator and 40 ml of 1% mepivacaine. Approximately 10 minutes after the injection, she complained dyspnea, shortness of breath and right mid-thoracic pain. Her oxygen saturation decreased from 100% to 95%. Diagnostic workup revealed right diaphragmatic elevation caused by phrenic nerve block. General anesthesia was induced because of the unsuccessful brachial plexus block and dyspnea with chest pain. She recovered without any residual complications and was discharged on the third postoperative day. Phrenic nerve block is a common complication in supraclavicular brachial plexus block but it is usually not severe and reassurance is enough to control it. However, pre-operative physical conditions that may lead to decreased respiratory reserves, such as morbid obesity should be considered as a risk factors when conducting supraclavicular brachial plexus block.

The Effect of Vertebral Wedge Angle to the Change of Kyphotic Angle by the Posterior Instrumentation Method in Thoracolumbar Spine Fracture / 대한척추외과학회지

STUDY DESIGN: Retrospective study OBJECTIVES: To examine the effect of transpedicular screw fixation on fractured vertebrae about the vertebral wedge angle (VWA) after posterior instrumentation of the thoracolumbar fracture, determine the effect of reduced VWA on the change in the Kyphotic angle (KA), and minimize loss of reduction of KA. SUMMARY OF THE LITERATURE REVIEW: Maintenance of the KA of a thoracolumbar fracture after surgery is important for the radiologic and functional outcome. MATERIALS AND METHODS: Forty patients, who had undergone posterior instrumentation in a thoracolumbar fracture between February 2006 and February 2008 and followed-up for more than one year, were enrolled in this study. The patients were divided into two groups according to transpedicular screw fixation (Group A) or not (Group B) including fractured vertebrae. The evaluation was performed by measuring the changes in the KA and VWA taken after the injury, immediate after surgery and 1 year after surgery. RESULTS: There was correlation between groups A (transpedicular screw fixation on fractured vertebrae) and B (no transpedicular screw fixation on the fractured vertebrae) regarding the correction of the VWA and the loss of correction KA, (p<0.05). CONCLUSIONS: Reduction of the VWA is an important factor for preventing reduction loss of the KA, and transpedicular screw fixation including fractured vertebrae would help reduce the VWA. Therefore, the operator must pay attention to the increase in VWA to maintain the KA through short segment transpedicular screw fixation including fractured vertebrae.

The correlation between the effects of propofol on the auditory brainstem response and the postsynaptic currents of the auditory circuit in brainstem slices in the rat / 대한마취과학회지

BACKGROUND: Although there have been reports showing the changes of the auditory brainstem response (ABR) waves by propofol, no detailed studies have been done at the level of brainstem auditory circuit. So, we studied the effects of propofol on the postsynaptic currents of the medial nucleus of the trapezoid body (MNTB)-lateral superior olive (LSO) synapses by using the whole cell voltage clamp technique and we compared this data with that obtained by the ABR. METHODS: 5 rats at postnatal (P) 15 days were used for the study of the ABR. After inducing deep anesthesia using xylazine 6 mg/kg and ketamine 25 mg/kg, the ABRs were recorded before and after intraperitoneal propofol injection (10 mg/kg) and the effects of propofol on the latencies of the I, III, and V waves and the I-III and III-V interwave intervals were evaluated. Rats that were aged under P11 were used in the voltage clamp experiments. After making brainstem slices, the postsynaptic currents (PSCs) elicited by MNTB stimulation were recorded at the LSO, and the changes of the PSCs by the bath application of propofol (100 microM) were monitored. RESULTS: We found small, but statistically significant increases in the latencies of ABR waves III and V and the interwave intervals of I-III and III-V by propofol. However, no significant changes were observed in the glycinergic or glutamatergic PSCs of the MNTB-LSO synpases by the application of propofol (100 microM). CONCLUSIONS: Glycinergic or glutamatergic transmission of the MNTB-LSO synapses might not contribute to the propofol-induced changes of the ABR.

Sinus arrest during valsalva maneuver after pneumonectomy: A case report / 대한마취과학회지

We report a case of cardiac arrest in a 71 year old male during the Valsalva maneuver that had been performed immediately after completing a pneumonectomy. The patient had a subclinical atrial septal defect (1.08 cm sized) and he previously undergone a left upper lobectomy of the lung without complications 11 months earlier. He underwent a left completion pneumonectomy due to recurrent lung cancer. After surgery a Valsalva maneuver was performed with 35 cmH2O to relocate the mediastinum. During this procedure, the patient experienced a cardiac arrest and was resuscitated with difficulty. It is believed that the cardiac arrest was due to pulmonary hypertension, right ventricular failure and right to left shunt caused by several factors, such as the pneumonectomy, subclinical atrial septal defect (1.08 cm sized), and Valsalva maneuver. In addition, the hypovolemia caused by fluid restriction and the epidural injection of local anesthetics might have contributed to this incident. Although it is a rare complication, it is suggested that subclinical ASD can cause severe hypoxemia, dyspnea even cardiac arrest after pneumonectomy. In order to avoid these complications, ASD should be treated with percutaneous closure or surgical intervention. If these are not possible, care must be taken when anesthetizing the patient, and anything that can increase the pulmonary vascular resistance and right to left shunt should be avoided.

Surgical Treatment for Descending Necrotizing Mediastinitis / 대한흉부외과학회지

BACKGROUND: Descending necrotizing mediastinitis (DNM) is a serious disease originating in odontogenic or oropharyngeal infection with high mortality despite adequate antibiotics and aggressive surgery. We analyzed results of treatment for DNM. MATERIAL AND METHOD: We studied 8 cases diagnosed as DNM from 1998 to 2007. All patients received emergent surgical drainage and debridement with broad spectrum antibiotics just after diagnosis. Antibiotics were changed after bacterial susceptibility testing. The surgical approach included 2 cases of cervicotomy, 6 cases of cervicotomy, and a thoracotomy. RESULT: The interval between symptom onset and hospitalization was 4.6+/-1.8 days (1~9 day). DNM originated in 4 cases of odontogenic infection (50%), 2 cases of oropharyngeal infection (25%), and 2 cases of unknown origin (25%). Causative organisms were found in 6 cases; Streptococcus in 4 cases, Staphylococcus in 1 case, and Klebsiella in 1 case. The Endo DNM classification was type I (2 cases), IIA (3 cases), and IIB (3 cases). The incidence of thoracotomy was 75%. The surgical mortality rate was 25% (2/8). The cause of death was multiple organ failure caused by septic shock. All mortality cases received only cervicotomy and aggravated infections after initial drainage. CONCLUSION: Early diagnosis, immediate surgical drainage, and adequate antibiotics, including covered anaerobes, are required. Thoracotomy should be performed with cervicotomy even for localized DNM.