Awake during General Anesthesia with BispectralIndex Value of 35

Awareness of intraoperative events in patients under general anesthesia is rare, but awareness during anesthesia is a serious complication that leads to anxiety and post-traumatic stress disorder. The Bispectral Index (BIS) has generally been accepted as a measurement of hypnosis under anesthesia. It is derived from a processed electroencephalogram and computer algorithm that assigns a numerical value based on the probability of consciousness. A 46-year-old, 65-kg male without underlying disease underwent elective surgery for ventral hernia. The patient in this case was administered an anesthetic that we frequently use and then average BIS value are 35. But he experienced awake during general anesthesia. We describe the first case of intraoperation awake under BIS 40 using desflurane.

The Cardiovascular Effects of Thoracic Epidural Injection of Ropivacaine during Sevoflurane General Anesthesia / 대한마취과학회지

BACKGROUND: Thoracic epidural anesthesia (TEA) combined with general anesthesia is commonly used in major upper abdominal surgery. The advantages of this method is the suppression of the perioperative stress response, the improvement in endocardial perfusion, and the reduction of myocardial oxygen consumption, postoperative morbidity and mortality. In particular, this method reduces the level of postoperative ileus and intestinal anastomosis leakage during gastrointestinal surgery. However, there is the possibility of severe cardiovascular depression using this combination method. This study evaluates the cardiovascular effects of extensive TEA combined with sevoflurane general anesthesia. METHODS: Fifty patients scheduled subtotal gastrectomy were enrolled in this study. After administering a bolus injection of 20 ml of 0.375% ropivacaine through an epidural catheter during sevoflurane general anesthesia, mean arterial pressure, heart rate, stroke volume, cardiac output, and systemic vascular resistance measured by Hemosonic (HemoSonic(TM) 100, Arrow, USA) every 5 minutes over a 30-minute period after the injection. RESULTS: All the data showed a significant decrease from 5 minutes after the epidural bolus injection except for the stroke volume, but that was not important clinically. CONCLUSIONS: A thoracic epidural injection of 20 ml of 0.375% ropivacaine can be used safely during sevoflurane anesthesia without severe cardiovascular complications during upper abdominal surgery.

Effects of Continuous Epidural Infusion after Thoracic Epidural Anesthesia for Mastectomy on Postoperative Pain, Nausea and Vomiting / 대한마취과학회지

BACKGROUND: Breast cancer is the most common cause of tumors in Korean women. Until recently, oncologic breast surgery was performed by using general inhalation anesthesia. However, this anesthetic method is associated with incomplete postoperative pain control and significantly more postoperative nausea and vomiting (PONV). Therefore, this study examinated the value of thoracic epidural anesthesia (TEA) for a mastectomy, and evaluated the effects of a continuous epidural infusion on postoperative pain control and the PONV, which is known to be a better method than general anesthesia with intravenous patient controlled analgesia (IV PCA). METHODS: Sixty five patients scheduled for a mastectomy were randomly assigned and divided into two groups. The GA group underwent general anesthesia using O2-N2O-sevoflurane with IV PCA. The TEA group was injected with 20 ml of 0.375% ropivacaine with fentanyl 50microgram at T4-5. After surgery the visual analogue scale (VAS) score of postoperative pain and nausea was checked. RESULTS: The postoperative pain intensity was significantly (P < 0.05) lower in the TEA group at the postoperative period and during 6 hours compared with the GA group. Postoperative nausea intensity was significantly (P < 0.05) lower in the TEA group during 6 hours. CONCLUSIONS: These results suggest that TEA is a method suitable of regional anesthesia for a mastectomy and a continuous epidural catheter infusion is more effective on postoperative pain control than general anesthesia with IV PCA. In addition, it is a good method for decreasing the PONV to a similar level as IV PCA with antiemetics.

Transcutaneous Electrical Stimulation of the P6 Acupoint Reduces Postoperative Nausea after Minor Breast Surgery / 대한마취과학회지

BACKGROUND: The present study was undertaken to investigate whether the transcutaneous electrical stimulation of the P6 acupoint prevents postoperative nausea and vomiting (PONV) after minor breast surgery. METHODS: In this prospective, randomized, double-blind and placebo-controlled study, we investigated ASA I or II female patients who underwent minor breast surgery under general anesthesia using sevoflurane. We used a ReliefBand(R) device (NSTTM 600, Woodside Biomedical Inc, USA) for the transcutaneous electrical stimulation of the P6 acupoint. The patients were randomly divided into two groups; in the P6 group (n = 33) the activated ReliefBand(R) was placed at the P6 acupoint; in the placebo group (n = 33) the inactivated ReliefBand(R) was placed at the P6 acupoint. The ReliefBand(R) was applied 10 min before the end of surgery and it remained in place for 24 h. We evaluated the incidence and severity of PONV, and the need for palliative antiemetics during the first 6 h and 24 h after surgery. RESULTS: The incidence of nausea was significantly lower in the P6 group (33%) than in the placebo group (67%) during the first 24 h after surgery. The severity of nausea was also significantly lower in the P6 group than in the placebo group. However, the incidence of vomiting and the need for palliative antiemetics was not different between the two groups. CONCLUSIONS: Transcutaneous electrical stimulation of the P6 acupoint significantly reduced the incidence and severity of nausea, but not the incidence and severity of vomiting, for female patients undergoing minor breast surgery during the first 24 h after surgery.

Transcutaneous Electrical Stimulation of the P6 Acupoint Reduces Postoperative Nausea and Vomiting after Laparoscopic Cholecystectomy / 대한마취과학회지

BACKGROUND: It is believed that stimulation of the P6 acupoint minimizes nausea and vomiting, and has been used to prevent and treat nausea and vomiting in various situations. The present study was undertaken to investigate whether the transcutaneous electrical stimulation of the P6 acupoint prevents postoperative nausea and vomiting (PONV) in female patients undergoing laparoscopic cholecystectomy. METHODS: In this prospective, randomized, double-blind, placebo-controlled study, we investigated 59 ASA I or II female patients who underwent laparoscopic cholecystectomy under general anesthesia using isoflurane or enflurane. We used a ReliefBand(R) unit (NSTTM 600, Woodside Biomedical Inc, USA) for the transcutaneous electrical stimulation of the P6 acupoint. Patients were randomly divided into two groups; in the P6 group (n = 29) the activated ReliefBand(R) was placed at the P6 acupoint; and in the placebo group (n = 30) the inactivated ReliefBand(R) was placed at the P6 acupoint. The ReliefBand(R) was applied 10 min before the end of surgery and remained in place for 24 h. We evaluated the incidence and severity of PONV, and need for rescue antiemetics during the first 6 h and 24 h after surgery. RESULTS: No differences in age, weight, previous PONV history, or duration of anesthesia were present between groups. The incidence of PONV was significantly lower (34%) in the P6 group than in the placebo group (63%) during the first 24 h after surgery. The severity of nausea and vomiting was also significantly lower in the P6 group than in the placebo group. However, the need for rescue antiemetics was similar in the two groups. CONCLUSIONS: Transcutaneous electrical stimulation of the P6 acupoint significantly reduces the incidence and severity of PONV in female patients undergoing laparoscopic cholecystectomy during the first 24 h after surgery.

Relaxant Effects of Thiopental, Ketamine, and Propofol on Isolated Rat Tracheal smooth Muscle / 대한마취과학회지

BACKGROUND: Intravenous anesthetics may modify airway responsiveness. The author investigated the relaxant effect of thiopental, ketamine, and propofol on isolated rat tracheal smooth muscles. METHODS: The trachea of the rat was dissected and cut into 3-mm rings. The rings were mounted in a water-jacked organ bath filled with Krebs solution aerated with 95% O2 and 5% CO2 at 37degreesC. Thiopental, ketamine, and propofol were given randomly to each ring preconstricted with EC50 of acetylcholine from 10(-6) to 10(-3) M. The relaxation response was the tension during anesthetic equilibration, expressed as a percentage of the tension from EC50 of acetylcholine. RESULTS: Thiopental and propofol (10(-5) to 10(-3) M) relaxed acetylcholine-induced contractions in a dose dependent manner (P < 0.05). Ketamine in doses of 10(-5) and 10(-4) M constricted acetylcholine-induced contractions by 3.2% and 16.5% respectively (P < 0.05). But ketamine in a dose of 10(-3) relaxed acetylcholine-induced contractions by 76.4% (P < 0.05). The relaxation of tracheal smooth muscles was greatest in thiopental, and was least in ketamine (P < 0.05). CONCLUSIONS: All three intravenous anesthetics have an excellent relaxation of tracheal smooth muscles in rats, except in doses of 10(-5) and 10(-4) M of ketamine.

Effect of Pancuronium, Vecuronium and Atracurium to the Plasma Cholinesterase Activity / 대한마취과학회지

BACKGROUND: Succinylcholine is metabolized by plasma cholinesterase (PChE). When it was pretreated by small doses of nondepolarizing muscle relaxants in order to minimize the side effects, there are evidences to be associated with alteration in the duration of action. This study is investigated whether the responses would be related to the enzymatic activities. METHODS: In 21 adult patients, ASA class I or II, PChE levels were measured by the modified Garry method after induction of anesthesia (control value) and at 3, 10, 20 and 30 min following administration of pancuronium 0.1 mg/kg, vecuronium 0.1 mg/kg and atracurium 0.5 mg/kg. Data were expressed as mean (SEM). RESULTS: The levels of PChE were significantly lower (p<0.05) than the control values at 3, 10, 20 and 30 min after given pancuronium as 4764 (270), 4777 (261), 4796 (306) and 4740 (332) IU/L respectively and after given vecuronium as 5004 (341), 5051 (329), 4969 (340) and 4960 (340) IU/L respectively whereas enzyme levels after given atracurium were not significant differences to compare the control values as 5153 (336), 5136 (320) 5124 (312) and 5151 (275) respectively. CONCLUSIONS: The results of present study show that both pancuronium and vecuronium may possibly inhibit PChE activity but this was not affected by atracurium.

Effects of Succinylcholine on the Recovery of Vecuronium-induced Neuromuscular Block / 대한마취과학회지

BACKGROUND: Succinylcholine is commonly used for tracheal intubation during induction of anesthesia and followed by a nondepolarizing neuromuscular blocking drug for intraoperative muscle relaxation. We have determined whether the effect of succinylcholine used for endotracheal intubation on the recovery of vecuronium-induced neuromuscular block offers many changes in time course of neuromuscular block. METHOD: Forty ASA class 1 or 2 adult male patients were studied. Patients were premedicated with nalbuphine 10 mg and glycopyrrolate 0.2 mg and after induction of anesthesia with thiopental, anesthesia was maintained with 1~2% enflurane, and 50% nitrous oxide in oxygen. Twitch responses of adductor pollicis were measured acceleromyographically using 0.2 ms, 2 Hz, train of four (TOF) stimulation of ulnar nerve every 15 seconds. The patients were allocated randomly to following four groups; Ten patients received vecuronium 0.1 mg/kg only (group 1), remained thirty patients received succinylcholine 1.0 mg/kg first and vecuronium 0.1 mg/kg was administered at 0% (group 2, n=10), 25% (group 3, n=10), 75% (group 4, n=10) recovery of first twitch from succinylcholine-induced neuromuscular block respectively. RESULT: Clinical duration, recovery index, and TOF ratio of vecuronium were not significantly different between groups. CONCLUSION: Succinylcholine for endotracheal intubation during induction of anesthesia does not affect time course of action of vecuronium-induced neuromuscular block. The cause of this result suspect that the effect of succinylcholine might be masked by large dose of vecuronium (2XED95). Clinically, it is unlikely that prior administered succinylcholine 1 mg/kg influence the recovery of vecuronium-induced neuromuscular block.

The Isolated Arm Test for the Assessment of Neuromuscular Blockade / 대한마취과학회지

Subjects should not have any factors affecting neuromuscular transmission. Anestheisa was induced by a sleep dose of 2.5% thiopental sodium, and oxygen, nitrous oxide and lower concentration of enflurane were used for maintenance. When the patients were stabilized, the arm with electrode attached and an indwelling needle inserted into a vein on the back of the wrist, was elevated for 30 seconds to partially drain the blood from it and then pneumatic tourniquet inflated 30 to 40 mmHg above the systolic blood pressure around the upper arm, so that a small dose of relaxants (1/60 or 1/30 of the clinical dose; succinylcholine 1mg/kg, vecuronium 0.08 mg/kg, atracurium 0.2 mg/kg, pancuronium 0.08 mg/kg and alpha-tubocurarine 0.2 mg/kg) could be injected into the arm isolated from the systemic circulation. Thereafter, ischemia was maintained for 4 minutes to allow retrograde spread of some of the drugs into the capillary bed where neuromuscular block was established. At the end of 4 minutes after tourniquet applied, the tourniquet was released. Neuromuscular conduction was recorded using ABM monitor of the Datex Co. for neuromuscular transmssion by 40 mA 2Hz stimulaton to ulnar nerve 20 seconds interval. We confirmed the marked rundown of amplitude of muscle action potensial (MAP) in group injected very small doses throughout the isolated limb but no affect the evoked MAP in group injected into systemic circulation. Conclusively, even there are various factors affecting extent of block by the tournique; ischemic acidosis, concentration volume of drugs, amovnt of exsanguination and the state of vasculare bed, these were not thought to be a source of error for study. Therefore small doses of relaxants required wih this technique exclude the possibility of unwanted systemic side effects and can be reliable and effective for clinical study for neuromuscular transmission.

Anesthesia for Congenital Esophageal Atresia and Tracheoesophageal Fistula Combined with Subglottic Laryngeal Stenosis - A case report - / 대한마취과학회지

We experience a 1 day old female patient with congenital esophageal atresia and tracheoeso-phageal fistula combined with a subglottic laryngeal stenosis which was 2 mm in diamete. At the time of surgery, an attempt was made to intubate, but it was impossible to pass a tube beyond the vocal cord which was mormal in size and shape. Thus a gastrostomy was performed only under mask with pure oxygen and local anesthesia. The child died one day later due to respiratory failure. Congenital subglottic laryngeal stenosis combined with esophageal atresia and tracheoeso-phageal fistula is very rare, but it is a very critical anomaly to anesthesia and resuscitation. Therefore, in the case of esophageal atresia and tracheoesophageal fistula with signs of respiratory obstruction, the possible presence of subglottic laryngeal stenosis should be considered and accurately assessed.

The Effect of Pretreated Pancronium with Subpsralytic Dose on Neuromuscular Blocking Onset / 대한마취과학회지

This study was undertaken to investigate the effect of subparalytic doses of pancuronium on the its onset time of action during induction before endotracheal intubation. The patients were composed of 20 healthy female and 20 male adults which were ASA class l and ll. At the time of intubation, the control group received a pancuronium 0.08mg/kg as a single bolus after a 2.5% thiopental sodium 5mg/kg injection, and the pretreatment group received subparalytic dose of pancuronium 0.015mg/kg before the thiopental sodium injection and then followed by pancuronium 0.08mg/kg 3 minutes later. The degree of neuromuscular transmission was measured using the train of four stimulation of the ulnar nerve repeated every 20 seconds, and the time was measured when the 1st twitch height(T1) was changed to 85%, 75%, 50% and 25%. The results were as follows; the onset time of neuromuscular blocking action was quicker in female patients than in male patients, and was significantly more rapid in both sexes in the pretreated group by 23.3 to 63.8% compared to the control group.