Search

Background: It is difficult to achieve good postoperative analgesia in patients who undergo abdominal aortic surgery without epidural analgesia and who have a bleeding tendency or are undergoing anticoagulation therapy. Intravenous fentanyl analgesia can be used in such patients, but it occasionally causes respiratory depression. Dexmedetomidine is used to achieve postoperative sedation and analgesia without respiratory depression. We compared the methods used to achieve postoperative analgesia after abdominal aortic surgery., Methods: In the intravenous fentanyl analgesia group (group F, n = 15), 0.5 microg x kg(-1) x hr(-1) fentanyl infusion was initiated during operation and continued to the next morning. In the intravenous dexmedetomidine group (group D, n = 15), 0.4-0.7 microg x kg(-1) x hr(-1) dexmedetomidine infusion was commenced during the operation and decreased to 0.2-0.7 microg x kg(-1) x hr- in the next morning. In the control group (group C, n = 15), continuous intravenous analgesia was not used. The frequency of analgesic use, Ramsay score, PaCO2 value, and rate of nausea and shivering were evaluated on the next morning., Results: The frequency of analgesic use and Ramsay score were similar in groups F and D. The Paco2 value was higher in group F than group D., Conclusions: With regard to respiratory depression, intravenous dexmedetomidine analgesia is safer and more useful than intravenous fentanyl analgesia.

We report the clinical management of 2 adults with mental retardation because of trisomy 21 who were sedated with high-dose dexmedetomidine (DEX) alone during diagnostic cardiac catheterization (DCC). The first patient was a 25-year-old man with aortic regurgitation and ventricular septal defect. DEX increased his Ramsay sedation score; however, a high dose and bolus injection of DEX were required to perform an invasive procedure. Cardiovascular drugs were not administered and heart rate was maintained in the low 40s. The maximum predicted plasma concentration (pCp) of DEX was 2.3 ng/mL. The second patient was a 26-year-old woman who had developed hypoxia 20 years after palliative surgery for tetralogy of Fallot. High-dose DEX was administered to keep the bispectral index value below 70 and maintain an immobile state; her maximum pCp of DEX was 4.3 ng/mL. Percutaneous oxygen saturation was kept above 83%, because of the suspicion that DEX may increase the ratio of pulmonary artery flow to systemic artery flow. In both cases, no respiratory system complications occurred despite inspiration of room air, indicating the usefulness of DEX for DCC. However, because of DEX may affect DCC data, it is necessary to pay careful attention to the use of DEX during DCC.

A 69-year-old man with normal renal function underwent resection of a parotid tumor under general anesthesia. For tracheal intubation, rocuronium 0.6 mg x kg(-1) was administered, and for facial nerve stimulation, sugammadex 2 mg x kg(-1) was administered immediately after intubation. The operation time was 3 h. At the end of the surgery, sugammadex 2 mg x kg(-1) was administered again. Bleeding occurred 6 h after the surgery. During the second operation, rocuronium 0.6 mg x kg (-1) was administered for tracheal intubation. Maximal suppression was achieved 1 min 42 s after the administration of rocuronium, and the recovery time was 44 min. The times for both maximal suppression and recovery are similar to those when the same dose of rocuronium was used without sugammadex. The half-life of sugammadex is about 2 h. From the observations in this case, we think that after the completion of approximately 3 half-lives, a normal dose of rocuronium can produce the desired effect without the influence of residual sugammadex present in the plasma.

Background: Recently, rigid indirect laryngoscopes with integrated tube guidance such as Pentax-AWS (AWS) and Airtraq (ATQ) are clinically available. They are known to improve the laryngeal view and facilitate intubation compared to the Macintosh laryngoscope (MAC). However, whether these new devices are easy to learn for novice laryngoscopists is not well understood. We surveyed medical students regarding their usefulness in intubation procedure on mannequin., Methods: Sixty-six medical students with no intubation experience were enrolled. A short instruction including practice for four devices (MAC, Miller laryngoscope (MIL), AWS, and ATQ) was given. Four intubation procedures (one for each device) to the mannequin (Laerdal airway trainer) were performed. The time to place the tube, percentage of glottic opening (POGO), incidence of esophageal intubation and teeth click were recorded. Participants were asked to choose the best device for their use. For statistical analyses, ANOVA and Chi-square tests were used where appropriate, and P < 0.01 considered significant., Results: Time for intubation was significantly longer in ATQ (P < 0.01). POGO was significantly higher in AWS, but lower in MAC (P < 0.01). Complications were fewer in AWS (P < 0.01), and 70% of the participants chose AWS as the best device., Conclusion: With minimal instruction including practice, the AWS seemed to achieve safer intubation with better laryngeal view for novice laryngoscopists.

We safely administered dexmedetomidine (DEX) for sedation during spinal anesthesia in a very elderly patient. The patient was a 98-year-old woman who had hypertension, renal failure, and first-grade atrioventricular block. She was scheduled to undergo internal fixation for fracture of the femoral neck. Initially, DEX (6.0 μg/kg/h) was administered over 10 min, followed by continuous infusion at a dose of 0.7 μg/kg/h. Consequently, her Ramsay sedation score (RSS) increased to 5, and the patient did not grimace in pain while being turned to the lateral position. Epidural catheterization and spinal anesthesia were performed under sedation without any problem. The DEX dose was adjusted to maintain the RSS within 3-4. The surgical operation was performed smoothly without any problem. Since the hemodynamic condition was stable, administration of ephedrine (5 mg) was required only once during surgery. Percutaneous oxygen saturation was maintained at 98% or more; respiratory rate was within 15-21 tpm, and no ventilatory assistance was required. The maximum predicted plasma concentration (pCp) of DEX was 1.56 ng/mL, and the mean pCp of DEX during surgery was approximately 0.45 ng/mL. We found that DEX can be safely used for sedation during spinal anesthesia in a very elderly patient.

Background: We studied the effect of the initial loading dose of dexmedetomidine on hemodynamics in pediatric patient undergoing cardiac surgery., Methods: This study was on 10 children under ten who were scheduled for elective surgery for repair of the atrial and ventricular septal defect. The induction and maintenance of anesthesia were performed with total intravenous anesthesia (TIVA) using propofol and fentanyl. After closing the sternum, we administered dexmedetomidine as a loading dose of 1 microg x kg(-1) for 10 minutes followed by a maintenance infusion of 0.7 microg x kg(-) x hr(-1). During the study systolic blood pressure, diastolic blood pressure, heart rate, and central venous pressure were measured., Results: There were no significant changes temporalily in heart rate and central venous pressure. Systolic and diastolic blood pressure increased temporalily. They reached the maximum 15 minutes after starting dexmedetomidine. And 30 minutes later they returned to the baseline level., Conclusions: Any clinical problems leading to a major increase in blood pressure were not encountered. But these results suggest that it is necessary to devise a method of administration of dexmedetomidine in consideration of the patient's condition and the drug effect in severe cases.

Background: Stroke volume variation (SVV) has been shown to be a reliable predictor of fluid responsiveness. It has been reported that SVV is useful for perioperative fluid management. We evaluated SVV and hemodynamics after aortic declamping during abdominal aortic surgery., Methods: Patients scheduled to undergo abdominal aortic surgery were selected for this study. A FloTrac sensor was fitted to a 20 G cannula indwelled in the radial artery, and cardiac output (CO), central venous pressure (CVP) and SVV were continuously monitored. Patients were divided into two groups depending on pressure decrease after aortic declamping: above 50 mmHg (F group) and below 50 mmHg (N group). CO, CVP and SVV before and after the aortic declamping in the two groups were compared., Results: Thirty patients were included in this study (15 in the F group and 15 in the N group). Measurement points were 26 points in the F group and 28 points in the N group. SVV before aortic declamping in the F group was significantly higher than that in the N group. Rate of decrease in CO after aortic declamping in the F group was significantly higher than that in the N group. There was no difference in CVP between the two groups., Conclusions: The results of this study suggest that monitoring SVV during abdominal aortic surgery is useful.

Background: An anesthetic-sparing effect of dexmedetomidine has been shown in several studies. We investigated the effect of dexmedetomidine on anesthetic requirements in 24 patients undergoing cardiovascular surgery., Methods: Patients were randomly divided into two groups in which continuous infusion of dexmedetomidine was started before induction of anesthesia (DEX group, n = 12) or when closing the sternum (control group, n = 12). Dexmedetomidine was administered intravenously at 0.7 microg x kg(-1) x hr(-1) after a bolus infusion at 6.0 microg x kg(-1) x hr(-1) for 10 min. All patients received total intravenous anesthesia with propofol and fentanyl., Results: Mean effect-site concentration of propofol was significantly lower in the DEX group than in the control group (1.9 +/- 0.3 microg x ml(-1) vs 2.5 +/- 0.8 microg x ml(-1)). Mean effect-site concentration of fentanyl in the DEX group was significantly lower than that in the control group (1.93 +/- 0.41 ng x ml(-1) vs 2.67 +/- 0.70 ng x ml(-1)., Conclusions: The combined use of dexmedetomidine decreases anesthetic requirements in cardiovascular surgery.

We performed two successive operations in a 39-year-old pregnant woman with myasthenia gravis (MG) with perioperative administration of dexmedetomidine. The first was an emergency cesarean section at 28 weeks' gestation. The patient was administered vecuronium, a muscle relaxant during the operation. She was sedated with dexmedetomidine for prolonged postoperative intubation until she was conscious and the effects of vecuronium had worn off. Extubation was successfully performed within half an hour of regaining consciousness. The second operation was an extended thymectomy performed under general anesthesia. Dexmedetomidine was administered intravenously as an adjunctive anesthetic without vecuronium. Extubation was successfully performed immediately after the operation. Here, we report a successful perioperative management with dexmedetomidine in a patient with MG, without any complications. Although dexmedetomidine has been considered useful for perioperative management of patients with MG, further consideration regarding its use in such cases is needed.

We report a case of transfusion-related acute lung injury (TRALI) during coronary artery bypass surgery. A 73-year-old man developed severe hypoxemia after transfusion of platelet concentrate just before completion of surgery. The possibility of cardiogenic pulmonary edema was excluded by transesophageal echocardiography. A chest X-ray showed bilateral pulmonary edema, suggesting TRALI. Steroid therapy and administration of sivelestat sodium hydrate and vasopressors were started. The patient's PaO2 /FIO2 ratio increased from 56 to 223 within 12 hrs. Anti-HLA and antigranulocyte antibodies were detected in the donated blood products. We assume that the cause of this case was an immune reaction through anti-HLA and/or antigranulocyte antibodies. TRALI is a potentially life-threatening, underrecognized and under-reported complication of transfusion. A better understanding and awareness is needed for medical staffs.

Background: Objective structured clinical examination: OSCE is now widely used in educational scene in medical schools before medical students start their clinical training. However, the utility of OSCE on BLS education has not been confirmed yet. The effect of OSCE on BLS education was examined using questionnaires., Methods: Questionnaires on knowledge of resuscitation were distributed to 166 medical school students (100 students in 1999 semester without OSCE, 66 in 2004 semester with OSCE). The questionnaire included 13 questions based on the 1992 or 2000 guidelines for cardiopulmonary resuscitation. Six out of 12 questions were defined as "skill related questions" and the student who correctly answered all these "skill related questions" were thought to be competent for providing adequate BLS., Results: Competent student ratio was significantly higher in students with OSCE (48%, vs 20% without OSCE, P < 0.001). Thus OSCE was useful for medical student to establish BLS knowledge when compared with students without OSCE. However, this result also revealed that the acquired knowledge through OSCE did not last long. Although 98% of students actually passed OSCE, only half of them were competent on paper test during clinical training., Conclusions: OSCE improved medical students' knowledge of BLS, but did not contribute to prevent forgetting for a long time. Thus, reeducation in BLS is still necessary for students after passing OSCE.