Effects of Ketamine on Carbachol and Epidermal Growth Factor Contraction in Rat Trachea / 대한마취과학회지

BACKGROUND: It is well known that ketamine, a dissociative anesthetic, inhibits smooth muscle contractions induced by high KCl and receptor agonists such as carbachol, histamine and endothelin. It has been reported that the inhibitory effect is mediated by a decrease in Ca2+ influx through the plasma membrane in smooth muscle. However, the mechanism of action for ketamine is not fully understood. In the present study, the effect of ketamine on Ca2+ -dependent and -independent carbachol and epidermal growth factor (EGF) contractions was investigated in rat tracheal smooth muscle. METHODS: Tracheal smooth muscle strips from Sprague-Dawley rats were mounted in an organ bath with physiological salt solution (PSS, pH 7.4, 37oC). When high KCl and carbachol (1, 10 micrometer) induced contraction and verapamil and ketamine attenuated contraction, and when EGF or carbachol alone and EGF plus carbachol in Ca2+ free media induced contration and verapamil and ketamine inhibited contration, the changes in tention of the muscle strips were measured. RESULTS: 1) Ketamine inhibited the contractions stimulated by high KCl (70 mM) and carbachol (1, 10 micrometer) in a concentration-dependent manner. The inhibitory effect was more marked in the 1 micrometer carbachol preparation than in the 10 micrometer carbachol preparation. 2) Although the contraction induced by carbachol (1 micrometer) was attenuated by verapamil (10 micrometer), a voltage-dependent Ca2+ channel blocker, the degree of inhibition was not complete, but only partial. The verapamil-insensitive portion of the contraction induced by carbachol was completely inhibited by the cumulative application of ketamine. 3) EGF (1 mg/ml), a tyrosine kinase-associated growth factor, or carbachol alone did not induce contraction in Ca2+ -free PSS (1 mM EGTA). However EGF plus carbachol contracted tracheal smooth muscle in the Ca2+ -free media and it was completely inhibited by ketamine but not by verapamil. CONCLUSIONS: These results suggest that ketamine inhibits the smooth muscle contraction including both verapamil-sensitive and -insensitive Ca2+ increments and by Ca2+ -independent contraction mechanisms.

The Effect of the Body Position and CO2 Gas Insufflation on Airway Pressure and Compliance in Normal Subjects during Laparoscopy or Pelviscopy / 대한마취과학회지

BACKGROUND: Laparoscopic and pelviscopic techniques have rapidly increased in recent years. Laparoscopy or pelviscopy require carbon dioxide (CO2) insufflation and Trendelenburg or reverse-Trendelenburg position for operational convenience. Many studies were done about the effects of laparoscopic procedures. But simultaneous comparisons of end-tidal CO2 tension (PETCO2), peak airway pressure (Ppeak), plateau pressure (Pplat) and respiratory compliance (Cdyn), between Trendelenburg and reverse-Trendelenburg position are rare. We compared the airway pressure and compliance between the two positions during laparoscopic surgery. METHOD: Eighty patients were divided into 2 groups: for 10o reverse-Trendelenburg position (n=40, Group R) and 10o Trendelenburg position (n=40, Group T). Abdominal pressure was maintained at 10 mmHg by a CO2 insufflator, and minute ventilation was controlled with a constant tidal volume and fixed respiratory rate. We observed the change of PETCO2, Ppeak, Pplat, and Cdyn at 1 minutes before CO2 insufflation (control value), 2 min after position change, 5, 20, 30, 60 minutes after CO2 insufflation, 2 min after CO2 removal, and 2 min after operation. RESULT: PETCO2, Ppeak, and Pplat were increased and Cdyn was decreased significantly after pneumoperitoneum compared with the control in group R. PETCO2, Ppeak, and Pplat were increased significantly under the Trendelenburg compared with the reverse-Trendelenburg, and Cdyn was decreased significantly in Trendelenburg compared with reverse-Trendelenburg. CONCLUSION: PETCO2, Ppeak, Pplat, and Cdyn impedances increased more under the Trendelenburg after pneumoperitoneum compared with reverse-Trendelenburg. We should pay more attention to patient with pulmonary disease, obesity, and old age under the Trendelenburg than reverse-Trendelenburg position.

The Pharmacodynamics and Infusion Rate of Mivacurium in Patients with Liver Cirrhosis or Cholestasis / 대한마취과학회지

BACKGROUND: Action of mivacurium varies in condition with reduced plasma cholinesterase activity. The aim of this study is to evaluate the pharmacodynamics of mivacurium and to obtain the infusion rate of mivacurium in patients with liver cirrhosis or cholestasis. METHOD: We allocated into three groups. Healthy subjects without hepatobiliary disease(Group I, n=10), patients with liver cirrhosis(Group II, n=5), and patients with cholestasis(Group III, n=9) received 5 mg/kg thiopental sodium and 1~2g/kg fentanyl. They were ventilated by mask with 2.5~3% enflurane(in O2/N2O 50%) until I/E ratio of enfurane concentration gt; or = 0.8, and then received 3 ED95 mivacurium(0.18 mg/kg). Accelerographic responses to train-of-four(TOF) stimulation of ulnar nerve at 15 seconds interval were used for neuromuscular monitoring. The onset time, the duration, recovery indices and infusion rate of mivacurium were compared among groups. RESULT: The durations from the injection of mivacurium to 10% single twitch recovered (Dur10) in group II(16.5+/-4.3 min) and III(17.1+/-0.6 min) were longer significantly than that in group I(10.7+/-5.3 min). The infusion rates to maintain a steady twitch height at 5~10% for 20 min in group II(1.9+/-1.5 microgram/kg/min) and III(1.6+/-0.7g/kg/min) were lower than that in group I(3.5+/-1.3 g/kg/min). However, there was no significant difference between group II and III. CONCLUSION: Clinical duration of relaxation with 3 ED95 mivacurium is prolonged significantly and infusion rate to maintain the steady twitch height at 5~10% is lower in patient with liver cirrhosis or cholestasis than in patient without hepatobiliary disease.

Dose Thoracoscopic Sympathectomy for Hyperhidrosis Increase Airway Pressure? / 대한마취과학회지

BACKGROUND: Bilateral interruption of the upper thoracic sympathetic chain at T2 level represents a selective cure for essential hyperhidrosis. Following the surgical sympathectomy, significant changes in pulmonary function has been observed. Our hypothesis was that thoracic sympathectomy may increase airway resistance during mechanical ventilation and which may be attenuated by the anticholinergics. METHODS: 21 patients with essential hyperhidrosis in ASA physical status class 1 under going thoracoscopic sympathectomy, they were randomizely divided into two groups: glycopyrrolate premedication group (n=13) and non-premedication, control group (n=9). Glycopyrrolate 0.2 mg was administered 30 minutes before the induction of anesthesia. Blood pressure, heart rate, peak airway pressure, plateau pressure were measured at before and immediate after sympathectomy. Respiratory compliance and resistance were calculated. RESULTS: After thoracoscopic sympathectomy, there was significant increase in mean peak airway pressure (15 +/- 3 vs 18 +/- 3 cmH2O, P<0.05) and decrease in respiratory compliance (52 +/- 12 vs 45 +/- 10 ml/cmH2O, P<0.05) compared to baseline. However there was no significant difference between glycopyrolate premedication group and non-premedication group. Conclusion: Thoracoscopic upper dorsal sympathectomy in patients with essential hyperhidrosis causes increase peak airway pressure and decrease the compliance of respiratory system during mechanical ventilation.

Experience of Management in "Preadmission Anesthesia Consultation Clinic" / 대한마취과학회지

BACKGROUND: Some of elective surgical procedures may be postponed or cancelled due to inadequate preoperative assessment and preparation. To minimize this problem, our preadmission anesthesia consultation clinic had been designed and managed at the outpatient department. The case referral pattern and efficacy of the clinic were evaluated for 1 year. METHODS: The study was done collected prospectively on 881 patients referred to the clinic from January to December 1997, 1 year. The age, sex, departmental distribution of consultation, ASA physical status of patients, the clinical department and reasons of consultation, and satisfaction of the patients or their parents were analized prospectively. The preoperative hospital stay periods before and after the opening of the clinic were compared. RESULTS: The sex ratio(M/F) were 6/4. Thirty-seven percent of the patients were under 10 years old and 11.8% were twenties. ENT(48.4%), ophthalmology(15.6%), general surgery(12.6%) were mainly referral departments. Reasons for consultation were related to chest X-ray abnormality(28.9% of the cases) and EKG abnormality(17.9%). The majority of consultation had pediatric(30%) and cardiologic problem(26%). URI(54.2%) and liver disease(12.6%) were major disease entities to postpone their surgery. In 2.7% of the patients, their admission or operation were postponed by the anesthesiologists in the clinic. Ninety-one percent of the patients were satisfied to visit the clinic. CONCLUSION: We conclude that reduction in preoperative hospital stay and shortening in delay of surgery are provided, and most patients are satisfied to the preadmission anesthesia consultation clinic.

The Effects of Acute Renal Failure on Mivacurium-induced Neuromuscular Blockade in the Cat / 대한마취과학회지

BACKGROUND: Mivacurium is mainly metabolized by plasma cholinesterase. However, the duration of action may be changed in various conditions such as liver dysfunction. To evaluate the action duration and recovery of mivacurium under the experimental acute renal failure, the pharmacodynamic studies were done. METHODS: The pharmacodynamic studies were done using a common peroneal nerve-anterior tibialis muscle preparation in 12, either sex, adult cats(weight 2.0~4.0 kg). The acute renal failure was made by the ligation of bilateral renal pedicles 1 hour prior to the pharmacodynamic study. All the cat received 5XED95 of mivacurium. The action durations and recovery indices were measured. And plasma cholinesterase activities were measured at each event. RESULTS: The duration of mivacurium was not prolonged with acute renal failure group(17.20 5.48 min.) compared to control group(13.48 4.30 min.). The recovery indices were not increased in the acute renal failure group(3.56 0.58 min.) as compaired with the control group(2.82 0.99 min.). CONCLUSIONS: The mivacurium-induced neuromuscular blockade is not prolonged by the experimental acute renal failure.

There is not Different Between the Patient-Controlled Lumber Epidural and Thoracic Epidural Analgesia with Morphine for Postthoracotomy Pain / 대한마취과학회지

BACKGROUND: With different injection levels, the dose-requirements of epidural opioids association with lipid solubility are controversial. The purpose of this study was to compare the effect of patient controlled lumbar(L group) and thoracic(T group) epidural morphine on dose-requirements, analgesia and side effects after thoracotomy. METHODS: Twenty patients were randomly assigned into one of two groups. Before the induction of general anesthesia, the epidural taps with 17G with Tuohy needle were done on the 6th or 7th thoracic and 2nd or 3rd lumbar intervertebral levels, respectively. The epidural catheter tips were placed 3~4 cm above the needle tips in either groups . Morphine 3 mg in 3 ml normal saline was administered via the epidural catheter in all the patients immediately at the end of surgical manipulation. PCA/basal infusion dose and lockout interval was 0.02 mg/once, 0.08 mg/hr and 5min respectively. After the initial dose dose-requirements were checked at 4, 8, 24 and 48hour and pain was assessed on visual analogue scale at 1, 4, 8, 24 and 48hour. Side effects were observed. RESULTS: There were no significant difference between groups in the dose-requirements of morphine, their analgesia and side effects. CONCLUSIONS: Lumbar epidural morphine provides postoperative analgesia after thoracotomy that is clinically indistinguishable from that provided by thoracic epidural morphine with respect to dosage, quality of analgesia and side effect.

Effects of Cutaneous Burn Injury and Resuscitation on the Cerebral Circulation / 대한마취과학회지

BACKGROUND: Despite the importance of burn-induced encephalopathy, cerebral hemodynamics after burn injury and during resuscitation remains undefined. The aim of our study was to evaluate the effects of a large cutaneous burn injury on the cerebral circulation. METHODS: Anesthetized sheep(n=8) were prepared with vascular catheters, a urinary catheter and a Richmond bolt for intracranial pressure monitoring. A scald injury was inflicted on 70% of total body surface area with hot water. Resuscitation was started 30 minutes after scald with Ringer's lactate to restore and then maintain baseline oxygen delivery. Resuscitation maintained blood pressure, cardiac output and urine output at normal levels. Brain blood flow was measured with colored microspheres. RESULTS: During resuscitation intracranial pressure rose slowly from 10.6+/-1.5 to 17.0+/- 4.0 mmHg(P<0.05) and cerebral perfusion pressure was reduced from 86.4+/- 6.8 to 64.1+/- 2.8 mmHg(P<0.05). During early resuscitation cerebrovascular resistance declined to maintain brain blood flow and oxygen delivery at baseline or better. After 6 hours, cerebrovascular resistance was inappropriately increased during a period of reduced cerebral perfusion pressure which resulted in brain blood flow being half the baseline levels. CONCLUSIONS: These data suggest that autoregulation maintains brain blood flow immediately after burn shock and early resuscitation, but autoregulation may be less effective as burn resuscitation proceeds.

Effect of Anesthesia and Surgery on Serum Interleukin-6 Levels / 대한마취과학회지

Increasing evidence suggests that many of the systemic responses that occur after injury and infection are related to elabolation of cytokines by the host. Cytokines are a diverse poup of polypeptides released from activated reticuloendothelial cells, which have multiple biological activities. But there is a paucity of information on the effect of anesthesia on plasma cytokine levels and little information on cytokine release following surgery. We studied plasma cytokine levels and hemodynamic parameters during anesthesia, surgery, and post operation 1 day. Sixty patients were studied. Patients were divided into two groups (G: general anesthesia with isofiurane, E:epidural anesthesia with 0.5% bupivacaine) according to the method of anesthesia. Venous samples were collected at the following time: a baseline sample 30 minutes before induction of anesthesia, at 10 minutes after induction of anesthesia, at 30 minutes after the induction of surgery, at 30 minutes after the end of anesthesia, and at 24 hours after the end of anesthesia. Arterial blood pressure and heart rate were measured at all time. Eight mililiter of peripheral blood was obtained for interleukin-6 studies in plain tubes. Plasma concentration of IL-6 was measured by IL-6 ELISA kit(Amershem Life Science, England). The results were as follows: 1) IL-6 did not change during general anesthesia but increased 30~40 fold at 30 minutes after the end of anesthesia and at 24 hours after the end of anesthesia. 2) IL-6 did not change during epidural anesthesia but increased 10~40 fold at 30 minutes after the end of operation and at 24 hours after the end of operation. 3) Arterial blood pressure and heart rate were unchanged during this experiment and there were no relationships between the change of interleukin-6 level and the arterial blood pressure and heart rate. The results suggest that the increment of IL-6 levels may be induced by the tissue damage or reaction of stress in operation with anesthesia. Isoflurane, NO2O and bupivacaine, however, may not increase the IL-6 level. Further researches will be needed that the effects of other anesthetics selection except isoflurane and bupivacane to IL-6 level and immunological mechanism.