Systemic hemodynamic effects of norepinephrine versus phenylephrine in intermittent bolus doses during spinal anesthesia for cesarean delivery

Background@#Norepinephrine, a potent α-adrenergic agonist with β-adrenergic effects, has recently emerged as a potential alternative to phenylephrine that does not lower cardiac output (CO) and heart rate (HR) during cesarean deliveries. We examined the systemic hemodynamic effects of both agents in this setting, using intermittent bolus doses to treat spinal anesthesia-induced hypotension. @*Methods@#A total of 56 parturients consenting to spinal anesthesia for elective cesarean delivery were randomly assigned to phenylephrine (100 μg/ml) or norepinephrine (5 μg/ ml) intermittent bolus dosing. The primary study outcome was maternal normalized CO, examining and other hemodynamic variables, maternal side effects, and fetal outcomes secondarily. @*Results@#In terms of systolic blood pressure and HR, there were significant within-group differences over time (P < 0.001 and P < 0.001, respectively). Normalized CO and stroke volume (SV) also showed significant differences between groups (P < 0.001 and P = 0.002, respectively). In the phenylephrine group, normalized CO and SV declined (relative to baseline values) by as much as 13% and 9%, respectively; whereas in the norepinephrine group, normalized CO did not differ significantly from baseline, and SV increased up to 5% (relative to baseline). Normalized total peripheral resistance likewise displayed significant within-group differences over time (P < 0.001). @*Conclusions@#During elective cesarean delivery, intermittent bolus doses of norepinephrine proved effective for treating spinal anesthesia-induced hypotension, while maintaining CO and SV. No maternal complications or fetal effects were evident.

Pneumocephalus during labor analgesia using the combined spinal-epidural technique / 대한마취과학회지

No abstract available.

The effect of midazolam dose and age on the paradoxical midazolam reaction in Korean pediatric patients / 대한마취과학회지

BACKGROUND: Although midazolam administration may occasionally induce a paradoxical episode, such as threatened crying and violent behavior in children, systematic studies on the causes of paradoxical reaction are limited. We investigated the effect of children's age and a dose of midazolam on the paradoxical reaction. METHODS: A total of one hundred sixty four children of 1-3 years and 3-5 years, were enrolled in this study. Each age group randomly received 0.05 mg/kg or 0.1 mg/kg of intravenous midazolam (41 patients/group). RESULTS: The incidence of paradoxical midazolam reaction in the study groups, 1-3 years with 0.1 mg/kg of intravenous midazolam, 1-3 years with 0.05 mg/kg, 3-5 years with 0.1 mg/kg, and 3-5 years with 0.05 mg/kg were as follows: 29.3%, 12.2%, 7.3% and 2.4%, respectively. The incidence among the 4 groups was significantly different (P = 0.002), highest in the 1-3 years receiving 0.1 mg/kg of midazolam (29.3%). Both age (P = 0.004, OR [95%CI] = 5.3 [1.7-16.8]) and dose of midazolam (P = 0.036, OR [95%CI] = 3.0 [1.1-8.4]) were risk factors. Perioperative clinical data including anxiety scales of children were not associated with the paradoxical midazolam reaction. CONCLUSIONS: In conclusion, we suggest that children less than 3 years old receiving higher dose of intravenous midazolam are at risk for the paradoxical midazolam reaction.

The comparison of clinically relevant doses of intrathecal ropivacaine and levobupivacaine with fentanyl for labor analgesia / 대한마취과학회지

BACKGROUND: Intrathecal labor analgesia using new local anesthetics such as ropivacaine or levobupivacaine becomes more popular by virtues of their safety and decreased motor weakness. However, the analgesic efficacy of the clinically effective intrathecal doses of these new local anesthetics combined with fentanyl has yet to be determined. METHODS: Sixty parturients who requested neuraxial analgesia in early active labor were randomly assigned to either ropivacaine (group R, n = 30) or levobupivacaine (group L, n = 30) group. Group R received 3 mg of intrathecal ropivacaine and the group L received 3 mg of intrathecal levobupivacaine mixed with 20 microg of fentanyl as part of a combined spinal-epidural (CSE) technique. The associated block parameters, such as pain scores, duration of analgesia, the highest levels of the sensory block and motor block scores 30 mins after the injection were compared between two groups. RESULTS: Intrathecal ropivacaine offered shorter analgesia (87 +/- 41 min vs. 122 +/- 56 min, P < 0.05) with lower sensory height (T8.5 vs. T6, P < 0.05) and led to lower incidence of complete analgesia (73 vs. 97%, P < 0.05) compared with intrathecal levobupivacaine. Although motor weakness was comparable in both groups, significantly weak perineal squeezing was noticed in Group L (7 of 30 parturients vs. 16 of 30, P < 0.05). CONCLUSIONS: Clinically relevant doses of intrathecal levobupivacaine in combination with fentanyl as part of a CSE technique provides more effective analgesia than equivalent doses of intrathecal ropivacaine in early labor, but is accompanied by slight motor weakness.

Dynamic left ventricular outflow tract obstruction in living donor liver transplantation recipients: A report of two cases / 대한마취과학회지

We present two cases of dynamic left ventricular outflow tract obstruction in 2 patients who were undergoing living donor liver transplantation. On the preoperative transthoracic echocardiography, the first patient showed normal ventricular function and a normal wall thickness, but severe hemodynamic deterioration developed during the anhepatic period and this was further aggravated after reperfusion in spite of volume resuscitation and catecholamine therapy. Intraoperative transesophageal echocardiography revealed the systolic anterior motion of the mitral valve leaflet together with left ventricular outflow tract obstruction. The second patient showed left ventricular hypertrophy with left ventricular outflow tract obstruction on the preoperative echocardiography. Intraoperative transesophageal echocardiography was used to guide fluid administration and the hemodynamic management throughout the procedure and a temporary portocaval shunt was established to mitigate the venous pooling during the anhepatic period. The purpose of this report is to emphasize the clinical significance of dynamic left ventricular outflow tract obstruction in patients who are undergoing living donor liver transplantation and the role of intraoperative echocardiography to detect and manage it.

Combined spinal-epidural anesthesia for caesarian section in a patients with multiple sclerosis: A case report / 대한마취과학회지

The use of neuroaxial blocks in patients with multiple sclerosis has been controversial, because the effect of local anesthetic drugs on the course of the disease is unclear. We report an obstetric patient with multiple sclerosis whose caesarian section was performed successfully under combined spinal-epidural anesthesia and postoperative pain control was managed using patient-controlled epidural analgesia. There were no exacerbation of neurologic symptoms and no relapse of disease at two month follow-up. We suggest that the choice of anesthetic technique for patients with multiple sclerosis should be determined after evaluation of the course of the disease and informed consent. The obstetric patients with multiple sclerosis should not be denied the neuroaxial block for labor and caesarian section.

Knotting of a guidewire during internal jugular vein catheterization in an infant: A case report / 대한마취과학회지

Central venous catheterization has been frequently used in pediatric patients in wide variety of conditions. Several authors have described about various complication of central venous catheterization in pediatric patients and reported complication rates of 3% to 6%. Knotting of guidewire as a complication of central venous catheterization has been reported in adult patients, but knotting of guidewire has not been reported in infants. Therefore we report an infant who experienced a knotting of guidewire during internal jugular vein catheterization which was successfully removed without any adverse events. We suggest that knot formation is possible in infants and there should be a high suspicion if resistance is felt at the time of catheter advancement.

Peripheral Arteriovenous Malformations with a Dominant Outflow Vein: Results of Ethanol Embolization

OBJECTIVE: To assess retrospectively the treatment results of ethanol embolization of peripheral arteriovenous malformations (AVMs) with a dominant outflow vein (DOV). MATERIALS AND METHODS: Nineteen patients who had peripheral AVMs with a DOV were enrolled in this study (mean age, 29.7 years; range, 15-42 years). Fifty-one ethanol embolizations (mean, 2.7; range, 1-8) were performed by direct puncture (n = 29), the transarterial approach (n = 13), the transvenous approach (n = 5), or a combination of methods (n = 4) under general anesthesia. Coil and/or core-removed guide wire embolization of the DOV or another flow occlusion technique (i.e., use of an external pneumatic pressure cuff) to achieve vascular stasis were required in all patients during ethanol embolization. Clinical follow-up (mean, 22.2 months; range, 1-53 months) was performed for all patients, and imaging follow-up (mean, 22.1 months; range, 2-53 months) from the last treatment session was performed for 14 patients. The therapeutic outcome (cure, improvement, no change, or aggravation) was assessed according to the clinical response and the degree of devascularization at angiography. RESULTS: Ethanol embolization was considered as an effective procedure in all patients. Thirteen (68%) of 19 patients were cured and six displayed improvement. Three of six patients with improvement needed further treatment sessions for residual AVMs. Four patients (21%) experienced a total of eight complications. Five complications (three events of a distal embolism and one event each of a urinary bladder necrosis and a brain infarct related to the accidental cannulation of the common carotid artery during insertion of the Swan-Ganz catheter) were major and three complications (skin necrosis) were minor. CONCLUSION: Peripheral AVMs with a DOV can be effectively treated with a high cure rate by the use of ethanol embolization alone or in conjunction with the use of coil and/or core-removed guide wire embolization.

Effect of Intraoperative 80% Inspired Oxygen on Postoperative Nausea and Vomiting in Patients undergoing Vitreoretinal Surgery / 대한마취과학회지

BACKGROUND: Most recently, the antiemetic effects of high inspired oxygen have been discussed and various results have been reported according to the types of surgeries and the groups of patients. In ophthalmic surgical patients, surgical procedures involving intraoperative manipulation of the eye and giving rise to residual eye discomfort were associated with the increased incidences of postoperative nausea and vomiting (PONV). The antiemetic effect of 80% inspired oxygen for the patients undergoing vitreoretinal surgery is unknown. Therefore, we examined the efficacy of 80% inspired oxygen in the decrease of the PONV incidences after vitreoretinal surgery under general anesthesia. METHODS: 170 adults under 70 years of age have received standardized sevoflurane anesthesia. After tracheal intubation, they were randomly assigned to two groups: 30% inspired oxygen in air (Group 30), and 80% inspired oxygen in air (Group 80). Postoperative nausea and vomiting were evaluated at the 2, 6, and 24 h postoperatively by an investigator unaware of patients' allocation. RESULTS: There was a significantly lower incidence of PONV during the first 2 h postoperatively in the Group 80 (22%) compared with the Group 30 (40%) (P = 0.024). The Group 80 (33.8%) showed the decreased incidence of PONV during the first 24 h postoperatively compared with the Group 30 (48.8%), but these differences were not statistically significant (P = 0.081). CONCLUSIONS: The use of 80% inspired oxygen during vitreoretinal surgery reduced the incidence of PONV during the first 2 h postoperatively.

Effect of Superior Cervical Sympathetic Ganglion Block on Brain Injury Induced by Focal Cerebral Ischemia/Reperfusion in a Rat Model / 대한통증학회지

BACKGROUND: Cerebral blood vessels are innervated by sympathetic nerves that originate in the superior cervical ganglia (SCG). This study was conducted to determine the effect of an SCG block on brain injury caused by focal cerebral ischemia/reperfusion in a rat model. METHODS: Male Sprague-Dawley rats (270-320 g) were randomly assigned to one of three groups (lidocaine, ropivacaine, and control). After brain injury induced by middle cerebral artery (MCA) occlusion/reperfusion, the animals were administered an SCG bloc that consisted of 30 microliter of 2% lidocaine or 0.75% ropivacaine, with the exception of animals in the control group, which received no treatment. Twenty four hours after brain injury was induced, neurologic scores were assessed and brain samples were collected. The infarct and edema ratios were measured, and DNA fragmented cells were counted in the frontoparietal cortex and the caudoputamen. RESULTS: No significant differences in neurologic scores or edema ratios were observed among the three groups. However, the infarct ratio was significantly lower in the ropivacaine group than in the control group (P<0.05), and the number of necrotic cells in the caudoputamen of the ropivacaine group was significantly lower than in the control group (P<0.01). Additionally, the number of necrotic and apoptotic cells in theropivacaine group were significantly lower than inthe control group in both the caudoputamen and the frontoparietal cortex (P<0.05). CONCLUSIONS: Brain injury induced by focal cerebral ischemia/reperfusion was reduced by an SCG block using local anesthetics. This finding suggests that a cervical sympathetic block could be considered as another treatment option for the treatment of cerebral vascular diseases.

Delayed Subarachnoid Migration of an Epidural Catheter: A case report / 대한마취과학회지

A 37-year old man was given thoracic epidural catheter insertion for the postoperative epidural analgesia one day before the liver transplantation as a donor. During the epidural catheterization, no complications were observed. Next morning, the patient complained of postural headache and cerebrospinal fluid leakage through the catheter was noted. We concluded that the epidural catheter had migrated into a subarachnoid space and removed the catheter. On the postoperative day three, epidural blood patch was performed resulting in symptom relief. Due to the possibility of accidental subarachnoid migration of epidural catheter, careful monitoring is recommended in a patient who is undergoing continuous epidural infusion.