Dongchul Lee

Total intravenous anesthesia without muscle relaxant in a patient with amyotrophic lateral sclerosis

A 63-year-old woman with amyotrophic lateral sclerosis (ALS) was scheduled for open reduction and internal fixation of the right tibia. Total intravenous anesthesia using propofol and remifentanil without muscle relaxant was selected as the anesthetic method, in order to avoid the possible occurrence of ventilatory depression due to abnormal responses to muscle relaxants and exacerbation of the motor neuron disease. After standard and neuromuscular monitoring devices were applied, anesthesia was induced and maintained with target controlled infusion of propofol and remifentanil in the range of 2.5–5.0 μg·ml−1 and 2.5–5.0 ng·ml−1, respectively. To avoid delayed neuromuscular recovery, we did not use any muscle relaxant at all. Intubation was successful and there were no remarkable events during anesthesia, except for three brief hypotensive events; there was no exacerbation of ALS itself during or after the anesthesia. She was discharged on postoperative day 3, without any discomfort.

The effect of oral and IV ramosetron on postoperative nausea and vomiting in patients undergoing gynecological laparoscopy with total intravenous anesthesia

PurposeRamosetron can be administered orally as well as intravenously. We investigated the effect of oral ramosetron on postoperative nausea and vomiting (PONV) in patients undergoing gynecological laparoscopy.MethodsOne hundred and twenty women were allocated randomly to one of three groups (n = 40 in each) to receive saline (control), 0.1 mg oral ramosetron (PO), or 0.3 mg IV ramosetron (IV). Total intravenous anesthesia (TIVA) with propofol and remifentanil was used in all patients.ResultsThe incidence of complete response (no PONV, no rescue) in the control, IV, and PO groups was: 65%, 90%, and 87.5%, respectively, during the first 1 h; and 67.5%, 87.5%, and 80%, respectively, during 1 to 24 h.ConclusionThe effect of oral ramosetron 0.1 mg was comparable to that of IV ramosetron 0.3 mg on the prevention of PONV in women undergoing gynecological laparoscopy with TIVA. Both the oral and IV forms were effective at preventing PONV during the first 1 h after surgery.

The intermittent sequential compression device on the lower extremities attenuates the decrease in regional cerebral oxygen saturation during sitting position under sevoflurane anesthesia.

Background The sitting position has potential for serious complications such as cerebral ischemia and venous air embolism. This study investigated the effects of intermittent sequential compression device (SCD) on the changes in regional cerebral oxygen saturation (rSO2) during the sitting position. Methods Sixty-six healthy patients undergoing shoulder arthroscopy in sitting position were randomly assigned to either control (N=33) or SCD (N=33) groups. Hemodynamic variables and the rSO2 were measured 5 minutes after the induction of anesthesia (Tsupine, baseline values), and 1, 3, and 5 minutes after raising the patient to a 70-degree sitting position (T1, T3, and T5). The incidence of hypotension was recorded. Results The incidence of hypotension was significantly higher in the control group (8/33) than that in the SCD group (1/33) (P=0.027, odds ratio 0.170, 95% CI 0.042-0.684). The rSO2 was significantly higher in the SCD group compared with those in the control group at T3 and T5. Within the group, rSO2 decreased significantly only in the control group compared with baseline value at T1, T3, and T5. The % change in rSO2 from T0 to T1, T3, and T5 were significantly lower in the SCD group compared to those in the control group. Conclusions The application of SCD to the lower extremities during sitting position under sevoflurane anesthesia was a simple and effective method to attenuate the decrease in cerebral oxygen saturation.

Stewart's physicochemical approach in neurosurgical patients with hyperchloremic metabolic acidosis during propofol anesthesia.

There is both in vitro and clinical evidence that high-dose propofol can inhibit mitochondrial respiration, resulting in metabolic acidosis. The purpose of this study was to evaluate the effects of propofol anesthesia on the acid-base status in neurosurgical patients with large amount of normal saline administration. Thirty patients undergoing clipping of cerebral aneurysm were randomly assigned to receive propofol (n=15) or isoflurane (n=15). Propofol dose (mean±standard error) infused for maintenance was 5.7±0.2 mg/kg/h in propofol group. Acid-base parameters such as PaCO2, pH, serum bicarbonate concentration, standard base excess, serum electrolyte concentration, total protein, albumin, lactate, and phosphate were measured before and 4 hours after the induction of anesthesia, and after surgery. The apparent strong ion difference (SIDa), the effective SID (SIDe), and the amount of weak plasma acid were calculated using the Stewart equation. There were no significant differences in pH, PaCO2, bicarbonate, and lactate between 2 groups throughout the whole investigation period. After surgery, standard base excess significantly decreased in both groups without intergroup difference. SIDa and SIDe significantly decreased in both groups, and lactate and strong ion gap significantly increased after surgery in propofol group, but there were no significant differences between 2 groups. Both propofol and isoflurane were associated with hyperchloremic metabolic acidosis in neurosurgical patients with large amount of normal saline administration. The acid-base balance between the 2 anesthetics was similar using Stewarts physicochemical approach.

Comparison of Intravenous Dexmedetomidine and Midazolam for Bispectral Index-Guided Sedation During Spinal Anesthesia

Background Despite the high frequency of hypotension during spinal anesthesia with proper sedation, no previous report has compared the hemodynamic effects of dexmedetomidine and midazolam sedation during spinal anesthesia. We compared the effects of bispectral index (BIS)-guided intravenous sedation using midazolam or dexmedetomidine on hemodynamics and recovery profiles in patients who underwent spinal anesthesia. Material/Methods One hundred and sixteen adult patients were randomly assigned to receive either midazolam (midazolam group; n=58) or dexmedetomidine (dexmedetomidine group; n=58) during spinal anesthesia. Systolic, diastolic, and mean arterial pressures; heart rates; peripheral oxygen saturations; and bispectral index scores were recorded during surgery, and Ramsay sedation scores and postanesthesia care unit (PACU) stay were monitored. Results Hypotension occurred more frequently in the midazolam group (P<0.001) and bradycardia occurred more frequently in the dexmedetomidine group (P<0.001). Mean Ramsay sedation score was significantly lower in the dexmedetomidine group after arrival in the PACU (P=0.025) and PACU stay was significantly longer in the dexmedetomidine group (P=0.003). Conclusions BIS-guided dexmedetomidine sedation can attenuate intraoperative hypotension, but induces more bradycardia, prolongs PACU stay, and delays recovery from sedation in patients during and after spinal anesthesia as compared with midazolam sedation.

Anesthetic management of a spontaneous spinal-epidural hematoma during pregnancy.

Spontaneous spinal-epidural hematoma is uncommon and rare during pregnancy. We were presented with a 31-year-old patient who developed back pain with lower extremity paralysis at 36 weeks of gestation. A magnetic resonance imaging scan demonstrated an acute spinal-epidural hematoma and therefore, an emergency cesarean delivery was performed followed by hemilaminectomy with hematoma removal. Anesthesia was initiated with a volatile-based technique which, following delivery of the baby, was changed to target-controlled infusions of propofol and remifentanil. Postoperatively, dopamine was infused to maintain the blood pressure within the high-normal range to optimize spinal cord perfusion. Successful anesthetic and postoperative management is described together with a review of the literature.

The clinical effective dose of rocuronium for lightwand tracheal intubation after induction with alfentanil, propofol, and low concentrations of sevoflurane

Background The aim of this study was to determine the clinical effective dose of rocuronium for tracheal intubation using a lightwand after induction with propofol, alfentanil, and a low concentration of sevoflurane. Methods Twenty-eight adults scheduled to undergo elective surgery lasting less than one hour were enrolled in this study. All patients received alfentanil (10 µg/kg) and propofol (1.5 mg/kg) for the induction of anesthesia. Tracheal intubation using a lightwand was attempted 3 minutes after administering rocuronium and mask ventilation with 2 vol% of sevoflurane. The initial rocuronium dose was 0.5 mg/kg. The rocuronium dose for consecutive patients, determined by Dixons up-and-down method, was increased or decreased by 0.05 mg/kg according to the result of the previous patient. The mean arterial pressure and heart rate were recorded before induction, 1 min before intubation, 1 and 2 min after intubation. Results The 50% clinical effective dose (cED50) of rocuronium for tracheal intubation using a lightwand was 0.20 ± 0.05 mg/kg according to Dixons up and down method. Isotonic regression revealed the cED50 and cED95 (95% confidence intervals) to be 0.20 mg/kg (0.10-0.3 mg/kg) and 0.35 mg/kg (0.16-0.49 mg/kg), respectively. Conclusions The cED50 and cED95 of rocuronium for tracheal intubation using the lightwand were 0.20 mg/kg and 0.35 mg/kg, respectively, after induction with alfentanil, propofol, and a low concentration of sevoflurane.