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

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.

Airway Management Failure after Delayed Extubation in a Patient with Oral Malignant Melanoma Who Underwent Partial Mandibulectomy and Reconstruction with a Free Flap.

Maxillofacial surgery may cause severe complications in perioperative airway management. We report a case of failed airway management in a patient who underwent segmental mandibulectomy, radical neck dissection, and reconstruction with a free flap. The patient was extubated approximately 36 hours after surgery. Approximately 7 hours after extubation, the patient complained of dyspnoea, and respiratory failure followed. Bag-mask ventilation, direct laryngoscopy, video laryngoscopy, and supraglottic airway access were ineffective. The surgical airway was secured with an emergency tracheostomy while performing cardiopulmonary resuscitation. However, the patient experienced permanent hypoxic brain damage. The airway of patients with oral cancer may be compromised postoperatively due to surgical trauma and bulky flap reconstruction. Patients should be closely monitored during the postoperative period to prevent airway failure. Early diagnosis and airway management before airway failure occurs are important. Medical staff should be aware of airway management algorithms, be trained to perform difficult airway management, and have the required equipment readily available.

Successful management of uncontrolled postpartum hemorrhage due to morbidly adherent placenta with Resuscitative endovascular balloon occlusion of the aorta during emergency cesarean section - A case report.

BACKGROUND: Morbidly adherent placenta (MAP) may cause life-threatening postpartum hemorrhage (PPH) requiring massive transfusions. Furthermore, it could endanger the lives of both mother and baby. Despite various efforts, such as adjuvant endovascular embolization and hysterectomy, massive PPH due to MAP still occurs and is difficult to overcome. CASE: Herein, we described the case of a 40-year-old woman with placenta previa totalis who experienced massive bleeding during a cesarean section. We used resuscitative endovascular balloon occlusion of the aorta (REBOA) and it improved the condition of the surgical field and the hemodynamic stability of the patient temporarily. The patient was successfully managed without further complications. CONCLUSIONS: REBOA can be used as a rescue procedure for uncontrolled bleeding situations in patients with MAPs. Anesthesiologists should consider and recommend REBOA as another resuscitative therapeutic option in the case of massive PPH.

Efficacy of minimal invasive cardiac output and ScVO2 monitoring during controlled hypotension for double-jaw surgery.

BACKGROUND: Controlled hypotension (CH) provides a better surgical environment and reduces operative time. However, there are some risks related to organ hypoperfusion. The EV1000/FloTrac system can provide continuous cardiac output monitoring without the insertion of pulmonary arterial catheter. The present study investigated the efficacy of this device in double jaw surgery under CH. METHODS: We retrospectively reviewed the medical records of patients who underwent double jaw surgery between 2010 and 2015. Patients were administered conventional general anesthesia with desflurane; CH was performed with remifentanil infusion and monitored with an invasive radial arterial pressure monitor or the EV1000/FloTrac system. We allocated the patients into two groups, namely an A-line group and an EV1000 group, according to the monitoring methods used, and the study variables were compared. RESULTS: Eighty-five patients were reviewed. The A-line group reported a higher number of failed CH (P = 0.005). A significant correlation was found between preoperative hemoglobin and intraoperative packed red blood cell transfusion (r = 0.525; P < 0.001). In the EV1000 group, the mean arterial pressure (MAP) was significantly lower 2 h after CH (P = 0.014), and the cardiac index significantly decreased 1 h after CH (P = 0.001) and 2 h after CH (P = 0.007). Moreover, venous oxygen saturation (ScVO2) decreased significantly at both 1 h (P = 0.002) and 2 h after CH (P = 0.029); however, these values were within normal limits. CONCLUSION: The EV1000 group reported a lower failure rate of CH than the A-line group. However, EV1000/FloTrac monitoring did not present with any specific advantage over the conventional arterial line monitoring when CH was performed with the same protocol and same mean blood pressure. Preoperative anemia treatment will be helpful to decrease intraoperative transfusion. Furthermore, ScVO2 monitoring did not present with sufficient benefits over the risk and cost.

The effect of low-dose rocuronium on rapid tracheal intubation using a video laryngoscope: A randomized double blind controlled study.

BACKGROUND: The aim of this study was to investigate the clinical effectiveness of rocuronium in low doses on conditions during rapid tracheal intubation using video laryngoscope. METHODS: Ninety-eight patients undergoing otolaryngologic surgery were randomly divided into 2 groups: group L using 0.3 mg/kg of rocuronium intravenously (n = 49) and group C using 0.6 mg/kg of rocuronium (n = 49). Sixty seconds after rocuronium administration, tracheal intubation was performed using a video laryngoscope. The overall intubation condition was evaluated along with specific conditions, including laryngoscopy condition, vocal cord position, and intubation response. Intubation profiles, including Cormack-Lehane grade, 1st attempt success rate, and intubation time, were also evaluated. RESULTS: Overall intubation conditions showed a significant difference between group L and group C (P = .003). Although the incidence of vigorous response after tracheal intubation was higher in group L than in group C (P = .022), laryngoscopy condition and vocal cord position were similar between the 2 groups (P = .145 and .070, respectively). Intubation profiles showed no differences between the 2 groups. The frequency and amount of additional rocuronium administration during surgery were also similar. CONCLUSIONS: Low-dose rocuronium provided significantly worse overall intubation conditions compared to the conventional dose of rocuronium for rapid tracheal intubation. However, when using a video laryngoscope, it may provide clinically acceptable laryngeal muscle relaxation.

Inspection of the nasopharynx prior to fiberoptic-guided nasotracheal intubation reduces the risk epistaxis.

BACKGROUND: Various complications may occur during nasotracheal intubation. This may include epistaxis and damage to the nasopharyngeal airway. We tested the hypothesis that the use of fiberoptic bronchoscopy (FOB)-guided intubation is superior to endotracheal tube (ETT) obturated with an inflated esophageal stethoscope. METHODS: Patients were randomly assigned to 1 of 2 groups (n=22 each): either an FOB-guided intubation group or ETT obturated with an inflated esophageal stethoscope group. After the induction of general anesthesia, patients in the FOB group received an FOB inspection through the nostril without advancement of ETT. Then, after confirming the placement of the bronchoscope tip in the trachea, the lubricated ETT was advanced via the nostril to the trachea along the bronchoscope. In the obturated ETT insertion group, the proximal opening of the ETT was blunted with an inflated esophageal stethoscope. The ETT was inserted into the selected nostril and advanced blindly into the posterior oropharynx. Then, the esophageal stethoscope was removed and tracheal intubation was performed with the bronchoscope. The number of attempts for successful tracheal intubation, the degree of difficulty during insertion, and bleeding during bronchoscopy were recorded. Another anesthesiologist, blinded to the intubation method, estimated the severity of epistaxis 5minutes after the intubation and postoperative complications. RESULTS: The FOB group had significantly less epistaxis during bronchoscopy, better navigability, and fewer intubation attempts and redirections. CONCLUSION: Fiberoptic-guided nasotracheal intubation was associated with less epistaxis. It also showed better navigability and less redirection rate. Therefore, FOB as an intubation guide is superior to ETT with an inflated esophageal stethoscope when intubating a patient via the nasotracheal route.

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

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.

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.

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

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.

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

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.