Dexmedetomidine for sedation in pediatric patients who received more than 20 sessions of radiation therapy: two cases report / 대한마취과학회지

Dexmedetomidine is a highly selective α2-adrenoceptor agonist that demonstrates anxiolytic and analgesic properties without inducing respiratory compromise, which makes it a suitable agent for procedural sedation and imaging studies. In our current case reports, intravenous dexmedetomidine infusion was used to provide sedation to 2 pediatric patients over more than 20 sessions of radiation therapy. On both occasions, dexmedetomidine provided adequate sedation without respiratory depression. However, the required dosage increased with repeated radiation therapy sessions.

Arrhythmogenic potential develops rapidly at graft reperfusion before the start of hypotension during living-donor liver transplantation / 대한마취과학회지

BACKGROUND: Detailed profiles of acute hypothermia and electrocardiographic (ECG) manifestations of arrhythmogenicity were examined to analyze acute hypothermia and ventricular arrhythmogenic potential immediately after portal vein unclamping (PVU) in living-donor liver transplantation (LT). METHODS: We retrospectively analyzed electronically archived medical records (n = 148) of beat-to-beat ECG, arterial pressure waveforms, and blood temperature (BT) from Swan-Ganz catheters in patients undergoing living-donor LT. The ECG data analyzed were selected from the start of BT drop to the initiation of systolic hypotension after PVU. RESULTS: On reperfusion, acute hypothermia of < 34degrees C, < 33degrees C and < 32degrees C developed in 75.0%, 37.2% and 11.5% of patients, respectively. BT decreased from 35.0degrees C +/- 0.8degrees C to 33.3degrees C +/- 1.0degrees C (range 35.8degrees C-30.5degrees C). The median time to nadir of BT was 10 s after PVU. Difference in BT (DeltaBT) was weakly correlated with graft-recipient weight ratio (GRWR; r = 0.22, P = 0.008). Compared to baseline, arrhythmogenicity indices such as corrected QT (QTc), Tp-e (T wave peak to end) interval, and Tp-e/QTc ratio were prolonged (P < 0.001 each). ST height decreased and T amplitude increased (P < 0.001 each). However, no correlation was found between DeltaBT and arrhythmogenic indices. CONCLUSIONS: In living-donor LT, regardless of extent of BT drop, ventricular arrhythmogenic potential developed immediately after PVU prior to occurrence of systolic hypotension.

Cerebral air embolism and subsequent transient neurologic abnormalities in a liver transplant recipient following the removal of the pulmonary artery catheter from the central venous access device: a case report / 대한마취과학회지

Cerebral air embolism is a rare but potentially life-threatening complication. We experienced a living-donor liver transplant recipient who presented with unexpected cerebral air embolism and transient neurologic abnormalities that subsequently developed just after the removal of the pulmonary artery catheter from the central venous access device. One day after the initial event, the patient's neurologic status gradually improved. The patient was discharged 30 days after liver transplantation without neurologic sequelae.

Comparing the effects of thiopental and propofol administration on the cardiovascular response as an induction agent during desflurane anesthesia

BACKGROUND: This study was undertaken to compare the hemodynamic effects of thiopental and propofol administration as induction agents during desflurane anesthesia. METHODS: One hundred twenty unpremedicated ASA physical status 1 patients who were aged 20-60 years and who scheduled for elective surgery under general anesthesia were randomly divided into two groups. In group T, thiopental sodium (5 mg/kg) was used to induce anesthesia, whereas propofol (2.5 mg/kg) was used in group P. In each group, the inspired concentration of desflurane was increased to 4.0 vol% shortly after a thiopental or propofol injection. After 10 manual baggings, the target was increased to produce an end-tidal concentration of desflurane (ETdesf) of 8.0 vol%, and this was maintained until the end of the study by adjusting the vaporizer setting. The heart rate (HR) and mean arterial pressure (MAP) were measured at baseline, 2 min and 5 min after induction and at 2 min after intubation. RESULTS: The heart rate was significantly increased in the two groups compared with baseline. In the P group, the mean blood pressure was decreased at 2 and 5 min after induction compared with baseline, whereas the mean blood pressure in the T group was significantly increased after induction. The mean blood pressure was significantly lower in group P than that in group T at 2 and 5 min after the injection of the induction agent. However, the heart rate did not differ significantly between two groups. CONCLUSIONS: During desflurane anesthesia, the heart rate did not differ significantly between the two groups, yet the mean blood pressure was significantly lower when using propofol than that when using thiopental sodium.

Effects of anesthesia on fluid volume kinetics after infusion of colloid solution during blood donation / 대한마취과학회지

BACKGROUND: The fluid kinetics of intravenously infused colloid during inhalation anesthesia and hemorrhage have not been investigated. We therefore assessed fluid space changes during infusion of hydroxyethyl starch solution after hemorrhage in conscious and desflurane-anesthetized individuals. METHODS: Following the donation of 400 ml of blood, 500 ml of hydroxyethyl starch solution was infused over 20 minutes into wakeful and desflurane-anesthetized volunteers. Blood was repeatedly sampled to measure hemoglobin concentration, a marker of plasma dilution, and fluid kinetic analysis was performed to evaluate changes in fluid space. RESULTS: Using a fluid kinetic model, we found that the mean volume of fluid space was 7,724 +/- 1,788 ml in wakeful volunteers and 6,818 +/- 4,221 ml in anesthetized volunteers, and the elimination rate constants were 7.1 +/- 3.5 ml/min and 19.4 +/- 4.6 ml/min, respectively. CONCLUSIONS: Infusion of colloid after mild hemorrhage resulted in similar expansions of plasma volume in desflurane-anesthetized and conscious individuals. During anesthesia, however, the expansion of plasma volume by colloid was decreased and of shorter duration than observed in conscious patients.