Rapid progressive atypical atraumatic osteonecrosis of humeral head: a case report / 대한마취과학회지

Osteonecrosis of the humeral head is an uncommon and slow progressive condition. This condition is difficult to be recognized because its initial symptoms are nonspecific. Simple radiography is the standard tool to stage disease progression. However, plain radiographic findings of osteonecrosis are nearly normal in the initial stage. We report a case of 74 years old female patient who have suffered from painful limitation of the shoulder joint. She had no trauma history and no specific predisposing factors for osteonecrosis of the humeral head. To confirm, follow up radiography and shoulder magnetic resonance imaging were performed.

Rhabdomyolysis in a chronic kidney disease patient after lung surgery / 대한마취과학회지

No abstract available.

Ipsilateral Reexpansion Pulmonary Edema Developed after Decortication: A Case Report / 대한구급학회지

Reexpansion pulmonary edema (RPE) is a rare but sometimes fatal complication of the treatment of lung collapse secondary to pneumothorax, pleural effusion, or atelectasis. We experienced a case of RPE that developed following decortication. A 46 year-old female had a decortication for pyothorax under one-lung anesthesia. There was no event during the operation and results of arterial blood gas analysis were within normal limits. After the operation, tracheal extubation was performed and 100% oxygen saturation on a pulse oximeter (SpO2) was maintained with 100% O2, (8 L/min) via mask ventilation with self-respiration. The patient, with 50% Venturi mask, was transported to the intensive care unit (ICU). On arrival at the ICU, a SpO2 of 80% was detected and arterial blood gas analysis revealed hypoxemia with acute hypercapnic respiratory acidosis. Fortunately, reexpansion pulmonary edema was detected early and intensive treatment was performed using mechanical ventilation with positive end-expiratory pressure. Tracheal extubation was performed after 1 day of mechanical ventilation. The reexpansion pulmonary edema was successfully treated and the patient recovered without any complications.

Spontaneous, Fulminant Gas Gangrene Caused by Klebsiella Pneumoniae: An Unrecognized Small Air Bubbles in the Left Femoral, External and Common Iliac Vein, and Inferior Vena Cava: A case report / 대한마취과학회지

Fulminant gas gangrene is a rare condition, usually associated with contaminated traumatic injuries. It carries a high rate of mortality and morbidity. Also, a number of studies have implicated non-traumatic gas gangrene, associated mostly with underlying diseases that cause immunodeficiency. We report a non-traumatic fatal case of Klebsiella pneumoniae gas gangrene with small air bubbles in the left external and common iliac vein, and inferior vena cava in a previously healthy male. We would like to recommend you do not use nitrous oxide in case of gas gangrene, because it can aggravate pulmonary air embolism.

What is an Optimal Effect Site Concentration of Remifentanil for Minimizing the Hemodynamic Change to Endotracheal Intubation using Light Wand? / 대한마취과학회지

BACKGROUND: In the previous studies, remifentanil reduces the hemodynamic change induced by endotracheal intubation. We studied the optimal effect site concentration of remifentanil for endotracheal intubation using light wand. METHODS: Sixty ASA 1 or 2 patients scheduled for elective surgery under general anesthesia were classified in three groups according to the TCI (target controlled infusion) dose of remifentanil. Each group was administered 4microgram/ml of propofol TCI, rocuronium, with 2 ng/ml (group 1), 4 ng/ml (group 2), 6 ng/ml (group 3) of remifentanil TCI. Blood pressure, heart rate and bispectral index score were measured before induction, 3 minutes after remifentanil and propofol TCI, after endotracheal intubation using light wand, and 3 minutes after endotracheal intubation. Statistical analysis was done for comparison of time and dose dependant change among the groups. RESULTS: After endotrachal intubation, blood pressure and heart rate were significantly increased in group 1, and decreased in group 2 and 3. 3 minute after endotracheal intubation, heart rate significantly decreased in group 3, but there were no changes in group 2. CONCLUSIONS: The spontaneous BRS was decreased during ketamine induction of general anesthesia. These results suggest that anesthesia induction with ketamine impairs baroreflex control of heart rate, which may provoke hemodynamic instability.

The Effect of Midazolam on Outward K+ Channel Currents in Rabbit Cerebral Arterial Smooth Muscle Cells / 대한마취과학회지

BACKGROUND: Midazolam has a direct relaxing effect on vascular smooth muscle, but the mechanisms that this agent produces muscle relaxation are not fully understood. The current study was performed to identify the effects of the midazolam on K+ channels current in rabbit cerebral arterial smooth muscle cells. METHODS: Whole cell patch-clamp recording technique was used to evaluate the effects of midazolam (0.1 to 100micrometer) on outward K+ channel currents in dispersed rabbit cerebral arterial smooth muscle cells. RESULTS: Outward K+ currents of rabbit cerebral artery smooth muscle cells were voltage-dependent. Midazolam (10, 100micrometer) tested significantly inhibited outward K+ currents in a dose-dependent manner and half-blocking concentration (IC50) was 15.94micrometer at 60 mV. CONCLUSIONS: Midazolam inhibit outward K+ currents of rabbit cerebral arterial smooth muscle cells. Further study will be needed to determine the effect of midazolam on calcium channel current because it is unclear if the inhibitory effect of midazolam on outward K+current induces vasoconstriction.

Does the Desire to Know about Information Related to Anesthesia and Surgery Differ according to the Coping Style Classified by the Amsterdam Preoperative Anxiety and Information Scale? / 대한마취과학회지

BACKGROUND: High monitors are patients who require information on anesthesia and surgery and generally carry out active searches. These patients will benefit from more information related to surgery preoperatively whereas low monitors will benefit from less detailed information. This study examined whether or not patients' desire for information related to anesthesia and surgery differ according to their coping style classified by the Amsterdam Preoperative Anxiety and Information Scale (APAIS). METHODS: 465 patients were asked to fill out the questionnaires in APAIS, State-Trait anxiety inventory (STAI) and also to mark their perception on a 10 cm line in a visual analog scale (VAS). The APAIS with the other subjective measurements of anxiety were evaluated according to their gender, ASA class, past history of surgery and degree of education. Thirteen questionnaires were evaluated according to their coping styles. RESULTS: High monitors wanted to know all 13 questions compared with low monitors, whereas low monitors preferred not to know (P < 0.05). The APAIS has a significant relationship with the VAS and STAI (P < 0.05). Women, patients with no prior history of surgery, and patients with ASA 2 were significantly more anxious than men, patients with a prior experience of surgery and ASA 1 patients, respectively (P < 0.05). The VAS and APAIS were in good agreement in defining patients as anxious and there were significant correlations between the two instruments (P < 0.05). CONCLUSIONS: The APAIS can be used as an efficient tool for identifying patients who are particularly anxious or require information.

Effect of Nitrous Oxide on Bispectral Index during Sevoflurane Anesthesia / 대한마취과학회지

BACKGROUND: Nitrous oxide is generally avoided in order to prevent either hypoxia or graft dislodgment during tympanoplasty. The aim of this study was to investigate the effect of nitrous oxide on the bispectral index during sevoflurane anesthesia at the anesthetic dose. METHODS: The bispectral index was continually measured during nitrous oxide-oxygen-sevoflurane anesthesia, discontinuation of nitrous oxide and the reintroduction of nitrous oxide. RESULTS: The bispectral index of nitrous oxide-oxygen-sevoflurane anesthesia increased after discontinuing the nitrous oxide and decreased after its reintroduction. CONCLUSIONS: Nitrous oxide decreased the bispectral index of nitrous oxide-oxygen-sevoflurane anesthesia compared with oxygen-sevoflurane anesthesia at the anesthetic dose.

The Comparison of Co-administration of Alfentanil-Propofol with Propofol in Insertion of Laryngeal Mask Airway / 대한마취과학회지

BACKGROUND: We performed a prospective, randomized, controlled trial to compare the quality, hemodynamic response, and recovery index of laryngeal mask airway (LMA) insertion after either propofol alone or co-administration of alfentanil-propofol anesthesia. METHODS: Sixty patients (ASA 1 or 2, 17-63 years) were randomly allocated to control and experimental group. Control group(Group I) was received placebo (saline), experimental groups were received alfentanil 10microgram/kg (Group II), 20microgram/kg (Group III), 30microgram/kg (Group IV). RESULTS: Loss of consciousness and LMA insertion were more rapid in patients with alfentanil 30 microgram/kg group than control group (P<0.05). In alfentanil 20microgram/kg group, loss of consciousness was more rapid than control group. Also, there were significant differences in propofol induction dose, effect site concentration on induction, and propofol maintenance dose between control and experimental group (P<0.05). CONCLUSIONS: We conclude that co-adminstration of alfentanil-propofol, especially 30microgram/kg group, compares favorably with propofol alone, although LMA removal time is prolonged.

The Effect of Halothane and Isoflurane on KCNK2 Transfected HEK-293 Cells / 대한마취과학회지

BACKGROUND: According to the report that KCNK activity in transfected COS-7 and HEK-293 cells was modulated by volatile anesthetics and activation of KCNK channels by neuroprotectants, the importance of KCNK2 were emphasized. In this study, we studied the effect of halothane and isoflurane on KCNK2 in the KCNK2 transfected HEK-293 cells. METHODS: Multiple patch clamp experiments with halothane and isoflurane were conducted to characterize KCNK2 in the KCNK2 transfected HEK-293 cells. KCNK2 cDNA were transiently transfected with FuGENE6 transfection reagents and whole cell recordings were made using predesigned pulse protocol. RESULTS: KCNK2 transfected HEK cells exhibited rapid rising, a time-independent, non-inactivating, outward-rectifying currents and had no threshold for activation by voltage. Multiple patch clamp experiments showed the presence of outward-rectifying K+ selective channels with a conductance of 1.31 +/- 0.59 nS (n = 16) at positive potentials. Recordings of halothane 448microM (-2 MAC) increased outward currents from control by 218% in standard saline perfusate (n = 4, P<0.05, paired t-test) and that of isoflurane 822microM (-3 MAC) increased outward currents by 172% in standard saline perfusate (n = 12, P<0.05, paired t-test). Channel activity enhanced during the duration of the exposure to volatile anesthetics returned to the baseline quickly upon wash. CONCLUSIONS: Considering the activation of KCNK2 by neuroprotectants such as riluzole and PUFA, we might think of the possibility of halothane and isoflurane as neuroprotectants because these anesthetics activated background K+ channels in KCNK2 transfected HEK-293 cells.

Spinal and Epidural Anesthesia in Two Severe Hypoxemia Patients: Two case reports / 대한마취과학회지

Severe hypoxemia is considered by many to contraindicate major surgery. Several studies have shown that dependency on oxygen, PaO2 or = 45 mmHg, FEV1 < or = 50%, and FVC < or = 75% are indicative of a high risk of morbidity and mortality following major surgical procedures. Here, we report our experience of the use of regional anesthesia in such patients. One patient was a 82-year-old female patient who was scheduled for partial hip replacement due to a fracture of the right femur. Her pulmonary function test and preoperative arterial blood gas analysis results were as follows: FVC 1.23 L (49.1%), FEV1 1.11 L (61.3%), FEV1/FVC 90.2%, a room air pH 7.423, PaCO2 43.0 mmHg, PaO2 46.4 mmHg, SaO2 84.5% and base excess 2.7 mM/L. Another patient was a 79-year-old COPD male patient scheduled for appendectomy. His immediate preoperative arterial blood gas analysis results were; room air pH 7.368, PaCO2 62.1 mmHg, PaO2 43.8 mmHg, SaO2 77.4% and base excess 7.3 mM/L. Both patients underwent and tolerated surgery safely with regional anesthesia. No permanent sequela occured postoperatively in these cases. No severe changes in room air arterial blood gas levels were observed before and after surgery. We present a review of two cases of severe hypoxemia in which a regional block was used.

What is an Optimal Dosage of Alfentanil for Minimizing the Hemodynamic Change to Endotracheal Intubation during Anesthesia Induction with Propofol Target-Controlled Infusion? / 대한마취과학회지

BACKGROUND: Laryngoscopy and tracheal intubation are associated with hemodynamic pressor responses, which can have adverse effects. During anesthesia induction with propofol target-controlled infusion (TCI), we aimed to determine the most appropriate dosage of alfentanil required for intubation, using a steady effect-site concentration of propofol and with the use of vecuronium. METHODS: Eighty ASA class 1 or 2 patients presenting for elective surgery were allocated at random to one of four groups. Anesthesia was induced in all patients with TCI of propofol target concentration 8 microgram /ml, followed by vecuronium (0.12 mg/kg). This was reduced to 5microgram/ml when the effect-site concentration had been 4microgram/ml. After the effect-site concentrations had reached to 5microgram/ml, control group received normal saline, group 1 received alfentanil 10microgram/kg, group 2 received alfentanil 20microgram/kg, and group 3 received alfentanil 30microgram/kg. Laryngoscopy and intubation were performed 90 s later. Heart rate was monitored continuously. Systolic blood pressure, diastolic blood pressure and mean arterial pressure were measured at pre-induction, post-induction (pre-intubation) and post-intubation, respectively. Complications such as hypotention and bradycardia were recorded until 5 minutes had elapsed after tracheal intubation. RESULTS: Control group showed significant increases associated with tracheal intubation in all hemodynamic variables (P < 0.05). Post-intubation values decreased significantly from pre-induction values in groups 1, 2 and 3 (P < 0.05). In groups 2 and 3, hypotension and bradycardia occurred (zero in group 1) but there were no significant differences in their incidences between the three groups. CONCLUSIONS: We suggest that alfentanil 10microgram/kg constitutes the optimal dosage to obtund the hemodynamic responses to tracheal intubation, using propofol TCI (5microgram/ml) and vecuronium for induction of anesthesia.

Effect of Thiopental and Ketamine on Endothelium-Dependent Relaxation Induced by Reactive Oxygen Species in Rabbit Thoracic Aorta / 대한마취과학회지

BACKGROUND: Reactive oxygen species (ROS) are free radicals that induce lipid peroxidation and cause tissue damage. ROS are frequently produced by ischemia and subsequent reperfusion in clinical situation and like coronary artery bypass graft surgery and transplantation. More over, some anesthetics are known to act as an antioxidants and free radical scavenger and, the aim of this study was to explore the scavenging effects of thiopental and ketamine against ROS induced by isolated rabbit thoracic aortic endothelial damage. METHODS: Twenty white male rabbits (weighing 2.0-2.5 kg) were used. Thoracic aorta and were dissected free, cut into rings (3-4 mm), and suspended in an organ bath filled with 10 ml Krebs solution bubbled with 5% CO2 and 95% O2 at 37oC. The rings were equilibrated for 90 min and the solution changed every 15 min, and then a resting tension of 1.5 g was applied to the rings. Isometric tensions were recorded using a transducer connected to a data acqusition system (Biopac Inc. USA). Aortic rings were precontracted with norepinephrine (NE, 10-6 M), and changes in tension were measured after the cumulative administration of acetylcholine (ACh 3 x 10-7, 10-6 and 3 x 10-6 M) and nitroglycerin (NTG 10-5 M). Data are expressed as percentages of the 10-5 M NTG-induced relaxation (ACh/NTG). Percentages of ACh/NTG, before and after ROS exposure by electrolysis were noted for control and experimental groups. Aortic rings were pretreated with thiopental (3 x 10-5, 10-4 and 3 x 10-4 M, n = 9, 13, 17), ketamine (10-4 M, n = 8), catalase (1000 U/ml, n = 12), mannitol (3 x 10-4 M, n = 5) or not pretreated (free, n = 6). After 30 minutes, with the rings were exposed to ROS by electrolysis (DC 9 V, 20 mA, aortic rings 1 cm removed from the anode) in Krebs solution for 2 minutes. After electrolysis, the organ bath fluid was replaced with fresh Krebs solution, and the aortic rings were precontracted with NE and was vasorelaxation with ACh and NTG as above mentioned concentrations. RESULTS: Endothelium-dependent vasorelaxation was induced in all concentrations of thiopental groups in a dose-dependent fashion (P <0.05 vs control value) even with ROS attack. The catalase group produced vasorelaxation after ROS attack (P <0.05 vs control value). On the other hand, no ACh-induced significant endothelium-dependent vasorelaxation after ROS exposure was observed in the ketamine and mannitol pretreated group, or in the free group (P <0.05 vs control group). CONCLUSIONS: These findings suggest that thiopental and catalase preserve ACh induced endothelium-dependent vasorelaxation and that thiopental has a dose-dependent ROS scavenging effect like catalase.

The Effect of Nickel and Manganese on Store-Operated Channels in Canine Pulmonary Arterial Smooth Muscle Cells / 대한마취과학회지

BACKGROUND: Pulmonary vasoconstriction greatly contributes to the elevated pulmonary vascular resistance in patients with pulmonary hypertension. A rise in cytosolic Ca2+ concentration ([Ca2+]cyt) in pulmonary arterial smooth muscle cells (PASMCs) is a major trigger for pulmonary vasoconstriction. Presently, little is known about the nature of the store-operated channels (SOCs) in PASMCs, even though store depletion-mediated capacitative Ca2+ entry (CCE) is a critical mechanism for refilling the empty sarcoplasmic reticulum (SR) with Ca2+, and for maintaining a sustained increase in [Ca2+]cyt. The goal of this in vitro study was to investigate the effects of nickel and manganese on store-operated channels in canine PASMCs. METHODS: Isolated PASMCs were obtained from an enzymatically treated canine pulmonary artery. Currents were recorded at room temperature using the dialyzed whole cell recording technique. The protocol used to deplete the intracellular Ca2+ stores and to monitor the development of the store-operated Ca2+ currents, involved voltage-clamping cells at 0 mV to inactivate any voltage-dependent calcium currents. Crrents were recorded in response to a 200 ms voltage step from 120 to 40 mV in 20 mV increments every 15 seconds. RESULTS: Simultaneous depletion of intracellular Ca2+ leads to a voltage-independent and linear store-operated Ca2+ current (ISOC) reversal near 0 mV. Nickel and manganese inhibit ISOC. CONCLUSIONS: In canine PASMCs, the depletion of intracellular Ca2+ stores leads to the activation of ISOC, which is inhibited by nickel and manganese. These metals are non-specific inhibitors of non-selective cation channels. Our results indicate that Ni2+- and Mn2+-sensitive pathways may mediate Ca2+ entry, or that a class of non-selective cation channels may contribute to CCE in canine PASMCs.

Protective Effect of Propofol on Endothelial Damage Induced by Reactive Oxygen Species in Rabbit / 대한마취과학회지

BACKGROUND: Reactive oxygen species (ROS) induce lipid peroxidation and tissue damage in the isolated rabbit thoracic aorta. The aim of this study was to explore the influence of the propofol and midazolam against ROS in the isolated rabbit thoracic aortic endothelium. METHODS: Eighteen white male rabbits (weighing 2.0-2.5 kg) were used. The thoracic aorta was dissected free and cut into rings (3-4 mm) and then suspended in a organ bath filled with 10 ml Krebs solution bubbled with 5% CO2 95% O2 at 37 degrees C. Aortic rings were then equilibrated for 90 min, and a resting tension of 1.5 g was applied. The Krebs solution was changed every 15 min. Isometric tension was recorded with transducer coupled to a data acqusition system (Biopac Inc. USA) on a PC. After precontraction with norepinephrine (NE, 10(-6)M), changes in tension were measured following the cumulative administration of acetylcholine (ACh 3x10(-7), 10(-6) and 3x10(-6)M) and nitroglycerin (NTG, 10(-5)M). Data are expressed as percentage of the 10 5 M NTG-induced relaxation (ACh/NTG). The ACh/NTG, before and after electrolysis were defined as the control and the experimental groups. The aortic rings were pretreated with propofol (3x10(-5), 10(-4), 3x10(-4) and 5.7x10(-4) M, n = 8, 10, 15, 13), midazolam (10(-4)M, n = 7), catalase (1,000 U/ml, n = 12), mannitol (3x10(-4)M, n = 5) or not pretreated group (Free, n = 6). After 30 minutes, the aortic rings were exposed to ROS generated by electrolysis (DC 9 V, 20 mA, aortic rings 1 cm away from electrode) in Krebs solution for 2 minutes, which was then changed for physiologic buffered salt solution. The aortic rings were precontracted with NE and vasorelaxation was induced with ACh and NTG at the above mentioned concentrations. RESULTS: Propofol produced vasorelaxation of NE-precontracted thoracic aorta in a dose-dependent fashion in all groups of propofol (3x10(-5), 10(-4), 3x10(-4) and 5.7x10(-4)M) even after ROS attack (P < 0.05 vs control value). Catalase produced vasorelaxation after ROS attack (P < 0.05 vs control value).On the other hand, ACh-induced significant endothelium-dependent vasorelaxation were not observed in the midazolam or mannitol pretreated group or the non-pretreated group (P <0.05 vs control group). CONCLUSIONS: These findings suggest that propofol and catalase preserve ACh induced endothelium-dependent vasorelaxation and that propofol has a concentration dependent ROS scavenging effect like catalase.

The Target Plasma Concentration of Propofol Required to Insert a Laryngeal Mask Airway without Muscle Relaxant Use / 대한마취과학회지

BACKGROUND: We evaluated laryngeal mask airway (LMA) insertion conditions, hemodynamic changes and bispectral index (BIS) responses during the induction of anesthesia with target controlled infusion (TCI) of propofol. METHODS: Ninety patients (ASA 1 or 2, 18-64 years) were allocated randomly to receive an infusion to achieve and maintain target blood concentration of a 4, 5 and 6micro gram/ml. LMA was inserted after loss of consciousness. LMA insertion conditions, hemodynamic and BIS responses were evaluated. RESULTS: Loss of consciousness and LMA insertion were more rapid in patients with propofol target blood concentration of a 6micro gram/ml than at the other concentrations. Also, full attenuation of larygeal reflexes on the first try was greater in the 6micro gram/ml group than the other groups. CONCLUSIONS: We conclude that propofol administration at a target blood concentration of 6micro gram/ml allow successful insertion of LMA without major hemodynamic changes.

The Influences of Clonidine Premedication on the A-lineTM ARX Index and Hemodynamics during Anesthesia Induction with Propofol / 대한마취과학회지

BACKGROUND:Clonidine, an alpha2-adrenergic receptor agonist, has been shown to have a sedative effect and to suppress hemodynamics when used as a premedicant. We evaluated the change of AEP index and hemodynamics after clonidine premedication and induction with propofol. METHODS:The study design was a prospective, randomized, double-blind study. 90 patients who were scheduled for elective surgery were randomly assigned in 3 groups (Group 1, 2 and 3). In groups 2 and 3, the patients were administered 2 microgram/kg or 4 microgram/kg of i.v. clonidine 30 minutes before the induction of propofol anesthesia, respectively. We measured A-lineTM ARX index (AAI), systolic blood pressure, mean arterial pressure, diastolic blood pressure and heart rate at the ward; before the administration of clonidine premedication, before induction, just before intubation and 1 minute after endotracheal intubation, and compared these parameters among the 3 groups. RESULTS:Each dose of clonidine had a suppressive effect before the induction of anesthesia and suppressed hemodynamics successfully during intubation. In groups 2 and 3, the AAI was lower than in group 1 (P < 0.05), but 7 patients had bradycardia and 3 patients had been hypotensive in group 3. CONCLUSIONS: Intravenous injection of 2 microgram/kg clonidine as a premedicant reduced AAI significantly (P < 0.05) compared to the control group, with good hemodynamic stability. Therefore, we believe that AAI can be used to predict hypnotic state during propofol anesthesia.

The Influences of Clonidine Premedication on the Bispectral Index and Hemodynamics during the Induction of Anesthesia and Endotracheal Intubation with Propofol / 대한마취과학회지

BACKGROUND: The bispectral index (BIS) has been used as an indicator of a sedative state. In this study, we investigated the influence of intravenous clonidine 2 or 3 microgram/kg on the bispectral index and cardiovascular response to anesthetic induction. METHODS: The study design is prospective, randomized and double-blind. Ninety patients scheduled to undergo elective surgery under general anesthesia were divided into 3 groups. Each group received no premedication (group 1, n = 30), clonidine 2 microgram/kg (group 2, n = 30) and clonidine 3 microgram/kg (group 3, n = 30). The sedation and responsiveness scores of the Modified Observer's Assessment of Alertness/Sedation Scale (MOAAS/S) were measured before induction and the BIS, blood pressure, and heart rate were measured at before induction, after propofol injection, and after intubation. RESULTS: The BIS was significantly lower in groups 2 and 3 than in group 1 before anesthetic induction and intubation. Mean blood pressure was significantly lower in groups 2 and 3 than in group 1 before anesthetic induction, after propofol infusion and after intubation. Heart rate was also significantly lower in groups 2 and 3 than in group 1 after intubation. The sedation score and MOAAS/S were significantly lower in groups 2 and 3 than in group 1. CONCLUSIONS: Clonidine-premedicated patients appear to maintain stable hemodynamics during anesthetic induction and intubation. The bispectral index can be objectively used in clonidine-premedicated patients when evaluating the degree of sedation.

The Assessment of Explicit Memory and Implicit Memory after General Anesthesia for Cesarean Section Using the Process Dissociation Procedure / 대한마취과학회지

BACKGROUND: It is still unclear whether intraoperative events result entirely from moments of inadequate anesthesia. We used the process dissociation procedure to estimate implicit and explicit memory for words presented during elective cesarean sections. METHODS: Sixty patients undergoing elective cesarean sections were studied. We used a word stem completion test for memory testing. Four lists of words was played via headphones during cesarean section. During testing, two lists were used in the inclusion part (one target and one distractor list); the remaining two lists were used in the exclusion part. BIS was recorded on a computer during word presentation. RESULTS: The duration of surgery was 67.1+/-13.9 min. The mean BIS during word presentation was 73.4+/-2.5. In the inclusion part, target hit rates (i.e., the probability of responding sucessfully to a word presented during surgery) were statistically significantly higher than distractor hit rates (0.21 vs. 0.12), and in the exclusion part target hit rates were statistically significantly higher than distractor hit rates (0.17 vs. 0.11). During testing, none of the patients was able to recall the correct words presented during surgery when presented with the word stem aurally and visually. CONCLUSIONS: We found evidence of implicit memory after general anesthesia for cesarean section using the process dissociation procedure, and found that implicit memory can occur in the absence of conscious recall.

The Effect of Nicardipine on Capacitative Calcium Entry in Canine Pulmonary Arterial Smooth Muscle Cells / 대한마취과학회지

BACKGORUND: Capacitive calcium entry involves the influx of Ca2+ across the sarcolemma in response to the depletion of intracellular Ca2+ stores. Presently, little is known about the nature of the intracellular Ca2+ store (s) in pulmonary arterial smooth muscle cells (PASMCs), even though the unique contractile response of this tissue to hypoxia may at least partially involve the intracellular release of Ca2+ . The authors aimed to investigate the effects of nicardipine on capacitative calcium entry. METHODS: isolated pulmonary smooth muscle cells were obtained from enzymatically treated canine pulmonary artery. Currents were recorded at room temperature using the dialyzed whole cell recording technique. The protocol used to deplete intracellular Ca2+ stores and to monitor the development of the store-operated Ca2+ currents, involved cells being were voltage-clamped at 0 mv to inactivate any voltage-dependent calcium currents, which were recorded in response to a 200 ms voltage step from 120 to 40 mV in 20 mV increments. RESULTS: Simultaneous depletion of intracellular Ca2+ leads to linear store-operated Ca2+ current (iSOC) reversal near 0 mV. Nicardipine does not affect iSOC. CONCLUSiONS: in canine PASMCs, the depletion of intracellular Ca2+ stores leads to the activation of iSOC, which is not inhibited by nicardipine, a voltage-dependent Ca2+ channel (VDCC) blocker, indicating that VDCC blocked by nicardipine does not contribute to CCE in canine PASMCs.