Effects of Patients' Position on Blood Pressure and Heart Rate during Spinal Anesthesia for Axillo-femoral Bypass Surgery / 대한마취과학회지

BACKGROUND: Hypotension is one of the most common complications from the spinal anesthesia frequently used for surgery on the lower abdomen or extremities. It might be important in prognostic improvements to maintain cardiovascular homeostasis in elderly or patients with cardiovascular diseases. This study evaluated the effect of the patients' position on the preservation of cardiovascular stability when elderly patients suffering from hypertension undergo surgery for an axillo-femoral arterial bypass. METHODS: 24 patients with hypertension undergoing an elective axillo-femoral bypass surgery were examined. The patients were randomly allocated into two groups (Lateral 20 min group: patients with lateral position for 20 min after spinal anesthesia; Supine group: patients with the supine position immediately after spinal anesthesia). The observers recorded the hemodynamic variables, as well as the loss of sensation on both sides. RESULTS: Considering the changes in the arterial blood pressure and heart rate from the baseline values, patients in the supine group showed a greater decrease in arterial blood pressure and heart rate (P < 0.05). In the lateral 20 min group, there was a lower block level of cold sensation that reflected the sympathetic blockade at the non-operated site (P < 0.05). CONCLUSIONS: The lateral decubitus position for 20 min after spinal anesthesia can contribute to the maintenance of cardiovascular stability during unilateral axillo-femoral bypass surgery in elderly patients with hypertension.

Effect-site Target-Controlled Infusion of Propofol and Alfentanil for Laryngeal Mask Airway (LMA) Insertion in Ambulatory Breast Surgery without Neuromuscular Blockade / 대한마취과학회지

BACKGROUND: We performed this study to evaluate the appropriate effect-site concentrations of propofol and alfentanil for LMA insertion in ambulatory breast surgery without neuromuscular blockade. METHODS: Seventy-three ASA physical status 1 patients were enrolled. The administration of propofol and alfentanil was titrated versus bispectral index (BIS or = 80 mmHg) and heart rate (HR > or = 50/min), respectively. The condition of LMA insertion was assessed as grade 1 (excellent), 2 (acceptable), and 3 (poor) according to gag, cough, movement, and laryngospasm. We recorded SBP, HR and BIS before and after LMA insertion, the effect-site concentrations of propofol and alfentanil at the time of LMA insertion, and the LMA removal time at recovery. RESULTS: The condition of LMA insertion at first attempt was grade 1 in 71.6% of patients, grade 2 in 20.3%, and grade 3 in 8.1%. After the first attempt at LMA insertion, movement occurred in 25.7% and the BIS increased above 60 in 31.5%. The range of the effect-site concentrations of propofol and alfentanil at the first attempt were 2.0 6.0 (3.7 +/- 0.7)microgram/ml and 30.0 150.0 (71.6 +/- 24.4) ng/ml, which reflected a large inter-individual variability. The incidences of hypertension, tachycardia, hypotension, and bradycardia were 6.8%, 1.4%, 11.0% and 5.5%, respectively. The mean LMA removal time was 4.7 min. CONCLUSIONS: LMA was inserted successfully in 91.7% at first attempt and removed promptly at recovery. Movement and increase of BIS above 60 occurred frequently after the first attempt of LMA insertion with the effect-site target-controlled infusion of propofol and alfentanil without neuromuscular blockade.

Changes of Blood Pressure and Heart Rate According to the Effect-Site Concentrations of Alfentanil during Endotracheal Intubation with the Effect-Site Concentration of Propofol Fixed at 4microgram/ml / 대한마취과학회지

BACKGROUND: Propofol and alfentanil are frequently combined for general anesthesia. The purpose of this study was to characterize the appropriate effect-site concentration of alfentanil combined with an effect-site concentration of propofol of 4 microgram /ml during endotracheal intubation. METHODS: One hundred and thirty patients, aged 40-70 years and scheduled for abdominal surgery were randomly allocated to four groups according to the target effect-site concentrations of alfentanil: 0 ng/ml in the placebo group, 50 ng/ml in the P50 group, 75 ng/ml in the P75 group, and 100 ng/ml in the P100 group. All patients received a computer controlled infusion of propofol with an effect-site concentration of 4microgram/ml. After equilibration between plasma and effect-site was achieved, and the trachea of the patient was intubated. The assessments of hemodynamic changes were usually confined to the measurement of changes in systolic/diastolic blood pressure (SBP/DBP), mean arterial pressure (MAP), and heart rate (HR). Also, we checked the dose requirements of ephedrine and atropine used to correct hypotension and bradycardia. RESULTS: The use of alfentanil (especially 50 or 75 ng/ml) was effective at blunting the SBP increase during the few minutes after intubation. However, the dose requirements of ephedrine and atropine in the P100 group were significantly higher than those in other groups. CONCLUSIONS: The appropriate effect-site concentration of alfentanil combined with an effect-site concentration of propofol of 4microgram/ml during endotracheal intubation lies between 50 and 75 ng/ml.

Patient-controlled Sedation with Propofol and Alfentanil during Colonofiberscopy / 대한마취과학회지

BACKGROUND: The aim of this study was to examine the safety and efficacy of patient-controlled sedation (PCS) according to the lock-out time (LOT, 1 or 2 min) with a demand bolus of propofol and alfentanil fixed during a colonofiberscopy. METHODS: Fifty ASA physical status 1 or 2 patients who underwent a colonofiberscopy were enrolled in this study. They were provided with a PCS pump (Perfusor(R) fm, B Braun Germany, nominal infusion rate, NIR = 1,000 ml/h) containing propofol (9.1 mg/ml) and alfentanil (45.5microgram/ml) in order to self-administer a 2 ml bolus whenever they felt uncomfortable. The lock-out time (LOT) was set to 1 (n = 20, group 1) or 2 (n = 30, group 2) minutes. The Observer's Alertness/Sedation (OAA/S) score, D/A (delivery/attempt, %), blood pressure, heart rate, respiratory rate, SpO2, end tidal CO2 and bispectral index (BIS) were assessed and measured during and/or after the procedures. The verbal descriptive pain scores, as well as the patient's and endoscopist's satisfaction scale were assessed after the procedures. RESULTS: Intraoperative and postoperative pain scores, D/A, the patient's and endoscopist's satisfaction were similar in both groups. However, the lowest BIS values in group 1 was lower than in group 2 (70.3 +/- 12.2 and 77.6 +/- 6.8, respectively, P = 0.010). There were fewer patients whose lowest OAA/S score was <3 in group 2 (4/30) than in group 1 (11/20)(P = 0.002). CONCLUSIONS: With a demand bolus of propofol (18.2 mg) and alfentanil (91.0microgram) fixed, the incidence of over-sedation was higher at LOT 1 min than at LOT 2 min while the efficacy was similar in the PCS with a high NIR during the colonofiberscopy.

Clinical Status and Anesthetic Management of Very Low Birth Weight Premature Infants who underwent Surgical Closure of Patent Ductus Arteriosus / 대한마취과학회지

BACKGROUND: A delay in spontaneous closure of the patent ductus arteriosus (PDA) is frequent in premature infant and may lead to cardiopulmonary congestion and death. Surgical closure of the PDA in the premature infant can be a safe and effective procedure. Now, several centers prefer to eliminate the problem of transportation to operating room and adopt the policy of operating in the newborn intensive care unit (NBICU). So we investgated the anesthetic management and clinical status of premature infants who underwent surgical closure of PDA. METHODS: We analyzed retrospectively the anesthetic management and clinical status of eleven premature infants below 1,500 g birth weight. RESULTS: Range of gestational age of infants was 24-30 weeks. Most common cause of operation was failure of medical treatment. All infants had features of respiratory distresses and prematurity complications. Fentanyl, vecuronium, oxygen, and air constituted a anesthetic regimen. The body temperature remained stable. Systemic blood pressure with ligation of PDA increased to 66.3 17.4 mmHg (mean+/-SD). After operation, three infants died from complication of prematurity. There were no deaths directly related to operation. Four infants underwent operation in NBICU and also had no wound infections. CONCLUSIONS: Premature infants with PDA had associated complications of prematurity and were severely ill. If the infants did not respond to medical therapy, the PDA was closed by operation with adequate anesthesia. Furthermore, the operation can be performed safely and efficiently in the operating room or NBICU.

Changes in Epidural Pressure during Genernal Anesthesia / 대한마취과학회지

BACKGROUND: Epidural pressure is reported to change in accordance with intracranial pressure (ICP). As ICP changes during general anesthesia, it is also possible that epidural pressure may change during general anesthesia. The aim of this study was to obtain trends of epidural pressure change during general anesthesia. METHODS: Eighteen patients scheduled for gastrectomy were allocated for this study after obtaining informed consent. Epidural catheter was inserted at T7-8, T8-9 interspace before induction. Catheter was connected to a pressure transducer after calibration. General anesthesia was induced with thiopental sodium (5 mg/kg), succinylcholine (1 mg/kg), followed by 3% enflurane. Anesthesia was maintained with 50% N2O in oxygen and 1-2% enflurane with vecuronium (0.1 mg/kg). Each patients was mechanically ventilated with tidal volume of 10 ml/kg at a rate of 10 bpm. Epidural pressure was measured before induction, at the time of injection of thiopental sodium, succinylcholine, laryngoscopy, intubation, surgical incision, and 30 minutes after surgical incision. Stastical analysis was done using repeated measures of ANOVA with Helmert option (p<0.05). RESULTS: Epidural pressure significantly changed dynamically during general anesthesia. Epidural pressures increased at intubation and at 30 minutes after surgical incision when compared with those at the time of laryngoscopy and incision, respectively (p<0.05). CONCLUSION: Our study indicates that epidural pressures changes dynamically during induction period of general anesthesia and also showed possibility that epidural pressure monitoring could be used instead of more invasive direct ICP monitoring.

The Effect of Brain Hypothermia on Brain Edema Formation after Transient Ischemia / 대한구급학회지

BACKGOUND: When ischemia reduces blood supply, hypothermia remains the sine qua non for reducing demand. An alternative to whole body deep hypothermia is an isolated cerebral hypothermia via perfusion of cooled blood through one internal carotid artery. The goal of this study was to evaluate the effect of isolated cold hemisphere perfusion during the cerebral ischemia on the formation of brain edema. METHODS: The studies were designed to perfuse a saline solution into both carotid arteries with a different temperature (left 15degreesC, right 38degreesC) in the same animal. Cerebral ischemia was produced by a combination of the both carotid artery saline perfusion and systemic hypotension to a mean arterial blood pressure of 40 mmHg for 10 minutes. Ninety minutes after reperfusion, brain water contents were measured using the kerosene/bromobenzene density gradient and compared with warm saline perfusion and normal control group. RESULTS: Brain water content of cold saline perfusion hemisphere measured at 90 minutes after ischemia showed decreased water content compared to warm saline perfusion hemisphere (p<0.05). CONCLUSIONS: Cerebral cold saline perfusion during the ischemia decreased the formation of brain edema. These results showed hypothemia is one of the most effective ways to protect brain from the ischemia.

Effects of Ketamine and Clonidine for Caudal Analgesia Produced by Bupivacaine in Pediatric Ambulatory Surgery / 대한마취과학회지

BACKGROUND: Caudal block has proved to be a satisfactory method of providing perioperative analgesia for pediatric surgery in inguinal and perineal areas. This study was designed to evaluate the effects of ketamine or clonidine as an adjunctive of caudal block produced by bupivacaine. METHODS: One hundred ninety five children aged 1~10 years, undergoing surgery in inguinal and perineal areas as ambulatory cases, were randomly allocated to one of four groups after the induction of general anesthesia; 0.25 % bupivacaine 1 ml/kg(group B), 0.25 % bupivacaine 1 ml/kg with ketamine 0.5 mg/kg(group K), 0.25 % bupivacaine 1 ml/kg with clonidine 1 microgram/kg(group C), and local infiltration group(group L). Postoperative pain was assessed using an objective pain scale and the incidence of side effects, such as urinary retention and nausea/vomiting was observed after surgery. RESULTS: In the group B and L, OPS score was higher and analgesics were more frequently administered than group K and C at the recovery room and at home after discharge(p<0.05). There was no difference between the groups in the incidence of nausea and vomiting but urinary retention at the recovery room was more frequent in group C than other groups(p<0.05). CONCLUSIONS: Caudal block provided more effective postoperative analgesia than local infiltration. In caudal block, the addition of ketamine or clonidine prolongs the duration of postoperative analgesia without significant increase in side effects.

Hemodynamic Changes during Continuous Hyperthermic Intraperitoneal Perfusion for Gastric Cancer Patients with Peritoneal Seeding / 대한마취과학회지

BACKGREOUND: Hyperthermia is currently effective treatment against numerous cancer gastric cells' seeding on the peritoneal surface and floating in the cancerous ascites. We evaluated changes in hemodynamics during continuous hyperthermic intraperitoneal perfusion (CHPP) to determine strategies for safer general management during this procedure. METHODS: Ten patients with far-advanced gastric cancer were given surgical treatment followed by CHPP with anticancer drug. The body temperature, blood pressure, heart rate, central venous pressure, pulmonary artery pressure, cardiac output, electrolyte and blood gas were measured during pre-CHPP, CHPP and post-CHPP period. RESULTS: The blood temperature reached 39.3 +/- 0.4 degrees C(mean SD) during CHPP. Heart rate increased to 104.4 +/- 14.2 bpm and the cardiac index to 5.3 +/- 1.5 l.min 1.m 2 during CHPP. The mean arterial pressure remained stable during the study period. The systemic vascular resistance index decreased to 996.7 +/- 324.0 dynes.s.cm 5.m2. The mixed venous oxygen saturation fell during the first part of the CHPP period. CONCLUSIONS: This study suggest that the CHPP with anticancer drug may be safe in humans, provided that appropriate monitoring, cooling and technical support are applied.

The Effect of Intratracheal Pulmonary Ventilation on Dead Space and Airway Pressures in Rabbits with Acute Respiratory Failure Induced by Oleic Acid Injection / 대한마취과학회지

BACKGROUND: Intratracheal pulmonary ventilation (ITPV) was developed to allow a decrease in physiological dead space during mechanical ventilation. To reduce anatomic dead space, a reverse thrust catheter (RTC) is introduced into an endotracheal tube (ETT) through an adapter and positioned just above the carina inside the ETT. ITPV can be combined with pressure control mode of mechanical ventilation to make hybrid ventilation(HV). The effect of HV on the reduction of dead space was compared with that of conventional mechanical ventilation(CMV) in rabbits with acute respiratory failure. METHODS: Oleic acid of 0.06 ml/kg was injected to induce acute respiratory failure in 7 rabbits. PaO2 and PaCO2 were measured 30 minutes after the injection. Oleic acid was injected in another 7 rabbits to compare CMV with HV while increasing the respiratory rate(RR). Tidal volume, dead space(VD) and peak inspiratory pressure(PIP) were measured at the same RR. RESULTS: PaO2 decreased significantly from 467+/- 68 mmHg to 156 +/-26 mmHg at FIO2 1.0 after the injection of oleic acid. In another 7 rabbits, the VD's of CMV were 34+/- 10 ml, 27 +/-10 ml, 20+/- 6 ml, and 18+/- 3 ml at respiratory rate of 20/min, 40/min, 80/min and 120/min, respectively. The VD's of HV were 28 +/-11 ml, 16+/- 8 ml, 9+/- 4 ml, and 7+/- 3 ml at the same respiratory rates as in CMV. The VD's of HV were lower than those of CMV. The PIP's were lower in HV than in CMV. CONCLUSION: We conclude that HV, as the modification of ITPV, can be applied to acute respiratory failure to minimize the airway pressures and dead space of CMV.

Metric study of the upper airway in normal Korean adults with new radiologic lateral view of chest / 대한마취과학회지

Authors measured various portions of upper airway by use of new radiologic lateral view of chest in order to study the mean values of upper airway in normal Korean adults (n=100). The length between anterior teeth and the top of the epiglottis was 8.9+/-0.6 cm in male and 8.5+/-0.6 cm in female. The length beteen anterior teeth and the mid portion of trachea was 20.4 +/-0.7 cm in male and 18.8+/-0.8 cm in female. The length between anterior teeth and carina was 27.1+/-0.9 cm in male and 25.3+/-0.9 cm in female, while the length of trachea was 13.3+/-0.7 cm in male and 12.9+/-0.5 cm in female. The vocal cord and the carina were usually located at the level of the 5th cervicl and the 5th thoracic vertebra, respectively, in both sexes. This study also showed that the central portion of the trachea was located at the level of the lower border of the medial end of clavicle.

Two Cases of Generalized Muscular Rigidity, Hyperpyrexia, Unconsciousness and Autonomic Dysfunction after Spinal Anesthesia / 대한마취과학회지

Malignant hyperthermia is a fulminant hypermetabolic state of skeletal muscle induced by volatile inhalation anesthetics, succinylcholine, stress, exercise and etc. The primary signs of this disease included tachycardia, tachypnea, fever, generalized rigidity, metabolic and respiratory acidosis, central venous desaturation and hypercarbia as well as increasing endtidal CO2. Malignant hyperthermia is an utosomal dominant trait in human and quite different from the recessive trait in pig. There were some clinical reports that malignant hyperthermia can occur occasionally during and after spinal anesthesia. Now we also experienced two cases of generalized muscular rigidity, hyperpyrexia, tachycardia, hypotension, cardiae arrhythmia and slightly metabolic acidosis during and after spinal anesthesia. Those signs were very similar to malignant hyperthermia. And the two patients and someone among the family showed increased serum creatine kinase. There was no serum electrolyte imbalance such as natrium, ionized calcium and magnesium. And function tests of thyroid and parathyroid, electroencephalogram and brain computed tomogram were all within normal limit. So we suspected and concluded that it should be malignant hyperthermia. But we could not confirm that malignant hyperthermia, because of not doing halothane caffeine contracture test due to a lack of equipment in our hospital.

Enlargement of Parotid Glands Follwing Epidural Anesthesia / 대한마취과학회지

Salivary gland enlargement in association with anesthesia is an unusual complication first described in 1968. Since then, several additional reports have appeared. This report decribes a case of bilateral enlargement of parotid gland that developed in the recovery room. Anesthesia and surgery contribute to many faetors that predispose to the developement of this disorder. These-include dehydration, the suppression of oral secretions by the restricion of fluids, the use of medication with antisialagogue properties, and inhalation of unhumidified gases. The clinical manifestations, predisposing factors, and treatment are discussed.