The Effect of Clonidine Pretreatment on Cardiovascular Response and Seizure Duration according to Electroconvulsive Therapy / 대한마취과학회지

BACKGROUND: Elecroconvulsive therapy (ECT) is frequently associated with cardiovascular complications such as hypertension and tachycardia. The aim of this study was to evaluate whether clonidine given as an oral preanesthetic medication would influence the hemodynamic stress response, peripheral oxygen saturation and seizure duration which follows ECT. METHODS: Twenty-two ASA physical status I, II patients with major depressive disorders were included in a crossover study design and assigned randomly to either a control group who received placebo, or a clonidine group who received oral clonidine of 3 microgram/kg 90 min before preparation of ECT. All patients received glycopyrrolate 0.2 mg intramuscularly 60 min before anesthetic induction. Electrocardiography, pulse oximetry, and blood pressure monitors were applied to all patients. Patients were pre-oxygenated with 100% O2. Patients received thiopental 2.5 mg/kg and succinylcholine 0.5 mg/kg for anesthetic induction. Noninvasive mean arterial blood pressure (MAP), heart rate, and oxygen saturation were recorded just before test drug administration, immediately before ECT, and each minute for five minutes after ECT. The times from ECT stimulus to the cessation of clonic-tonic motor activity in the "isolated" arm were noted. RESULTS: There was a significant decrease in MAP (P = 0.007) through the peri-ECT period in groups with oral clonidine pretreatment (3 microgram/kg) relative to the control group. There were no significant differences in heart rate and peripheral oxygen saturation values between two groups. The duration of motor seizure activity was similar between the clonidine pretreatment and placebo groups. CONCLUSIONS: We conclude that oral clonidine 3 microgram/kg as a pretreatment medication is effective in attenuating the MAP increase in routine ECT.

Role of Fiberoptic Bronchoscopy in Conjunction with the Use of a Single Lumen Tube with Bronchial Blocker for Thoracic Anesthesia / 대한마취과학회지

BACKGROUND: Fiberoptic bronchoscopy has been recommended to verify the position of single lumen tubes with bronchial blockers (Univent(R) tube), but this remains controversial. The authors studied the role of a bronchoscopy for placing and monitoring bronchial blockers (BB) after blind intubation and after positioning the patient. METHODS: One hundred patients having thoracic surgery requiring a Univent tube insertion were prospectively studied. After "blind" tracheal intubations with Univent tubes, BB were advanced in the left-side mainstem bronchus for 60 patients and the right-side for 40 patients. A bronchoscopy was performed after conventional clinical verification of correct placement and after patient positioning for a thoracotomy. A BB was considered malpositioned when it had to be moved < 0.5 cm to correct its position. RESULTS: After "blind" BB intubation, clinical evidence of malpositioning was found in 5 patients. This was confirmed by fiberoptic assessment. In 95 patients in whom placement was judged correct by clinical assessment, malpositioning was detected by bronchoscopy in 39 cases. After patient positioning, BB were found to be displaced in 29 patients. Right-side BB were significantly more likely to be malpositioned than were left-side BB. CONCLUSIONS: After blind intubation and patient positioning, more than one third of BB required repositioning. A routine bronchoscopy is therefore recommended after intubation and after patient positioning.

The Influences of the Bispectral Index and Hemodynamics during Induction of Anesthesia with Propofol and/or Midazolam / 대한마취과학회지

BACKGROUND: The bispectral index (BIS) has been used as an indicator of sedative state and has been considered to be related to anesthetic agents and noxious stimulus. In this study, we measured BIS, blood pressure (BP) and heart rate (HR) during induction of anesthesia (IA) with propofol, with and without midazolam pretreatment. METHODS: A study design was used in 20 ASA physical status 1 and 2 patients aged from 18 to 60 years undergoing short (2 h) operation times. In the control group (group 1, n = 10), propofol 12 mg/kg/h was infused continuously after propofol 2 mg/kg as an intravenous bolus for IA preceded by normal saline. In group 2 (n = 10), propofol 12 mg/kg/h was infused continuously after half-strength propofol 1 mg/kg as an intravenous bolus for IA preceded by 0.1 mg/kg midazolam 2 min before. Patients received intravenous propofol for IA over 40 seconds. During the infusion, vecuronium (0.15 mg/kg) was given 3 5 min before intubation. The assistant and controlled ventilation were maintained with 100% oxygen over 5 min, and continued until BIS decreased to 40 and intubation was called for. The BIS, BP and HR were measured 2 min after midazolam or normal saline infusion, 3 5 min after propofol with vecuronium and 1, 3 and 5 min after endotracheal intubation. RESULTS: The midazolam pretreatment produced transient decreases in systolic BP and the BIS. During IA with propofol, BP decreased 20% in both groups. BIS decreased significantly 5 min after endotracheal intubation. CONCLUSIONS: Midazolam pretreatment attenuated the cardiovascular response to intubation, so BIS is considered a good monitor as a predictor of hypnotic state during intravenous anesthesia.

Effects of Intravenous Lidocaine on Intra-abdominal Pressure during Endotracheal Suctioning / 대한구급학회지

BACKGOUND: We evaluated the effect of intravenous lidocaine (1 mg/kg and 2 mg/kg) on intra-abdominal pressure (IAP) during endotracheal suctioning. METHODS: We studied 40 patients undergoing endotracheal intubation during mechanical ventilation. Group I (1 mg/kg) and group II (2 mg/kg)were given lidocaine double fashion. The endotracheal suctioning (ETS) was done 1, 3, 5 and 7 min after the injection of lidocaine. IAP, systolic blood pressure (SBP), diastolic blood preassure (DBP), and heart rate (HR) during ETS were recorded, IAP was measured using a transurethral bladder catheters. The cough response to ETS was classified as " cough score". RESULTS: Before administration of lidocaine, ETS produced significant increase in SBP, DBP, IAP and HR compared with baseline values in the two groups (p<0.05). Both groups showed no significant changes in SBP, DBP, and HR during the study. In group I, ETS produced a significant increase in IAP 5 and 7min after lidocaine treatment (p<0.05). There were significant differences between the two groups 5 and 7 min after lidocaine treatment (p<0.05). The score of cough decreased significantly in both groups 3 min after lidocaine treatment but there was a significant difference between the two groups at 7 min. CONCLUSIONS: We concluded that lidocaine pretreatment significantly blunted the increase in IAP, SBP DBP and HR caused by ETS and this effect lasts for 3 min in group I and 7 min in group II.

Anesthetic Management of Giant Intracranial Aneurysm / 대한마취과학회지

A 50 year-old woman was scheduled for clipping of giant middle cerebral artery (MCA) aneurysm. Preoperative four-vessel angiography and computed tomography scan revealed a giant aneurysm (3.5x3.3x3.5 cm) at bifurcation of right MCA. Induced hypotension and brain protection using sodium nitroprusside (SNP) and thiopental loading were planned to prevent cerebral damage during the operation. Before induction, esmolol, lidocaine and vecuronium were administered. Mask ventilation with isoflurane in N2O and O2 was performed over 5 minutes and then tracheal intubation was done. Anesthesia was maintained by isoflurane+N2O+O2 with pancuronium. Electrocardiography, pulse oxymetry, capnography, central venous pressure, evoked potential and invasive arterial blood pressure were monitored. She was hyperventilated intraoperatively with a PaCO2 around 30 mmHg. Perioperative hypotension was achieved with infusion of SNP (0.3~1.0 microg/kg/min). During the actual aneurysm surgery, mean arterial pressure was lowered to approximately 50 mmHg. Adjuvant drugs such as methylprednisolone, mannitol and furosemide to reduce intracranial pressure were also administered. This technique established good brain conditions during clipping of the aneurysm. A thiopental loading (4 mg/kg) was supplied while the aneurysm was approached. Satisfactory and well-controlled hypotension was obtained after thiopental and SNP. Postoperatively, the patient was transferred to the intensive care unit.