BACKGROUND: Fluid replacement after hemorrhage usually results in hemodilution, and hemodilution leads to increased cerebral blood flow, which is known to be beneficial to the outcome of ischemic brain damage. However, the effect of hemodilution may be different in patients with head injuries and increased intracranial pressure (ICP). The aim of this study was to evaluate the effects of normovolemic hemodilution on cerebral blood flow (CBF), brain tissue oxygen tension (PbtO2), and the severity of cryogenic brain injury, and to determine the acceptable limit of hemodilution during cryogenic brain injury. METHODS: Thirty New Zealand white rabbits were anesthetized with O2-N2O-isoflurane. Cryogenic brain injury (1 cm in diameter) was produced by applying liquid nitrogen on the surface of the right parietal bone for 90 seconds. Sixty minutes after cryogenic brain injury, acute normovolemic hemodilution was induced with 10% pentastarch for 30 minutes. In group I (n = 7), hemodilution was not induced. In groups II (n = 7), III (n = 8), and IV (n = 8), the hemoglobin concentrations were adjusted to 9-10, 6-7 and 3-4 g/dl, respectively. Mean arterial pressure, central venous pressure and ICP were measured, and local CBF and PbtO2 of the right parietal subcortex were continuously monitored. The rabbits were euthanized 150 minutes after brain injury, and the brains were removed and sectioned coronally through the center of the lesion. The extent of brain injury in the coronal plane was measured by light microscopic examination. The posterior part of the brain was divided into two halves and the water fraction of each part was measured by the dry-weight method. Data obtained were compared by the Kruskal-Wallis test or by repeated measures ANOVA. The difference was considered significant when P <0.05. RESULTS: No differences were observed in mean arterial pressure, central venous pressure or rectal temperature. However, significant differences were found in ICP, CBF and PbtO2 among the groups. ICP was significantly higher in group IV than in groups I and II. The CBF values of groups III and IV were higher than those of group I. The values of PbtO2 of group IV were lower than those of groups I and II. Normovolemic hemodilution, of up to 6-7 g/dl of hemoglobin, led to an abrupt increase in CBF and a subsequent increase in ICP. Hemodilution, of up to 3-4 g/dl of hemoglobin, decreased brain tissue oxygen tension significantly. No differences in the brain water fractions and the extent of cryogenic injury were found among the groups. CONCLUSIONS: It is concluded that the acceptable limit of acute normovolemic hemodilution in cryogenic brain injury is 9-10 g/dl of hemoglobin, as ICP and CBF do not increase and PbtO2 does not deteriorate.
Arterial Pressure ; Brain ; Brain Injuries ; Central Venous Pressure ; Craniocerebral Trauma ; Hemodilution ; Hemorrhage ; Humans ; Hydroxyethyl Starch Derivatives ; Intracranial Pressure ; Neutrophils* ; Nitrogen ; Oxygen ; Parietal Bone ; Propofol* ; Rabbits ; Rabeprazole

BACKGROUND: Propofol is widely used in neurosurgical anesthesia as an intravenous anesthetic agent. There have been some reports on the protective effects of propofol in cerebral ischemia. However conflicting results also exist. This study was designed to test the hypothesis that propofol pretreatment would provide protective effect on the focal cerebral ischemia-reperfusion injury. METHODS: Thirty Sprague-Dawley rats were divided into two groups; 15 for a halothane group, 15 for a propofol group. After induction of anesthesia with halothane in 100% oxygen, the tracheas were intubated and mechanical ventilation was maintained. For the entire experimental period normocapnia was maintained and scalp temperature was maintained in the range of 37 - 37.5oC. In the propofol group, propofol was infused at the rate of 2 mg/kg/min for 30 min without halothane administration prior to the ischemic period. In the halothane group, propofol was not infused. The left middle cerebral artery was occluded for 90 minutes with an intraluminal monofilament. After ischemia, perfusion was restored and rats were awakened. After 24 hours, the brain was removed and sectioned coronally and immersed in the 2% 2,3,5-triphenyltetrazolium choride solution. Percent mean infarcted area was calculated and compared between groups by Wilcoxon rank sum test. RESULTS: The percent infarcted area of halothane and propofol groups was 18.8 +/- 19.2% and 15.7 +/- 16.4%, respectively. There was no difference between groups in the aspect of percent infarcted area and physiologic variables such as mean arterial pressure, scalp temperature and serum glucose concentration. CONCLUSIONS: The pretreatment of propofol does not produce protective effect on focal cerebral ischemia compared with treatment with halothane.
Anesthesia ; Animals ; Arterial Pressure ; Blood Glucose ; Brain Ischemia ; Brain* ; Halothane ; Ischemia ; Middle Cerebral Artery ; Oxygen ; Perfusion ; Propofol* ; Rats* ; Rats, Sprague-Dawley ; Reperfusion Injury ; Respiration, Artificial ; Scalp ; Trachea

BACKGROUND: Patient-controlled analgesia (PCA) is a widely used method of postoperative analgesia with the advantage of tailored dosing for each individual. In spite of its popularity, there have been few reports on the current state of PCA in Korea. In this study, the data on PCA management and PCA regimens of medical institutions in Korea were collected and analyzed. METHODS: Members of the Korean Society for Anesthetic Pharmacology were questioned as to the state of postoperative PCA management, such as acute pain services (APS) and pain assessment. A list of PCA regimens for each institution was also requested and analyzed. RESULTS: Among 65 hospitals, APS was run in 30 and the severity of postoperative pain was assessed in 60. The safety and efficacy of PCA was evaluated only in 9 hospitals. A total 518 PCA regimens were reported (414, 95 and 9 regimens for intravenous, epidural and other routes, respectively). For intravenous PCA, fentanyl only and fentanyl-ketorolac regimens comprised 33.8 and 30.9% of treatments, respectively. In 95.9% of the regimens, background infusion was used. For epidural PCA, fentanyl-ropivacaine or fentanyl-levobupivacaine regimens made up the majority (47.4 and 13.7%, respectively). CONCLUSIONS: In Korea, APS was used in less than 50% of the hospitals and the evaluation of the safety and efficacy of PCA is not carried out in the majority. Background infusion, known to have little advantage in most cases, was widely used in intravenous PCA.
Analgesia ; Analgesia, Patient-Controlled* ; Fentanyl ; Korea* ; Pain Clinics ; Pain Measurement ; Pain, Postoperative ; Passive Cutaneous Anaphylaxis ; Pharmacology

Genetic and/or environmental factors lead to large inter-individual variability in the efficacy and the side effects of drugs. Pharmacogenetics is the study of genetically determined differences in drug response. It focuses on the genetic variations involved in drug metabolism, transporters and receptors, which result in the pharmacokinetic and pharmacodynamic differences. Recently, pharmacogenetic studies on anesthetics and analgesics have been carried out actively. The pharmacogenetics of the commonly used drugs in anesthetic practice is reviewed.
Analgesics ; Anesthetics ; Genetic Variation ; Pharmacogenetics

No abstract available.
Resin Cements

Opioids are the cornerstone for treating moderate to severe pain and are commonly used for anesthesia and pain management. However, large inter-individual variability exists in the analgesic and adverse effects. It would be very helpful to predict the opioid response of each patient, considering the serious outcomes related to insufficient pain control and fatal side effects. Pharmacogenetic data on opioids have accumulated; thus, the aim of this article is to review the pharmacogenetic studies related to opioids frequently used for anesthesia and pain management.
Analgesia ; Analgesics, Opioid ; Anesthesia* ; Humans ; Pain Management* ; Pharmacogenetics*

No abstract available
Anesthetics, Intravenous* ; Pharmacogenetics*

BACKGROUND: The performance of a target controlled infusion (TCI) system needs to be confirmed in a clinical setting. Aquafol(TM), a microemulsion propofol, can be used for TCI with its pharmacokinetic parameters. The aim of this study is to evaluate the predictive performance of Aquafol(TM) TCI by using a PION TCI(R) pump incorporating the previously established pharmacokinetic parameters and ke0. METHODS: Thirty adult patients were enrolled in the study. General anesthesia was maintained with TCI of Aquafol(TM) and remifentanil using a PION TCI(R) pump. During the maintenance of anesthesia with a constant target effect-site concentration of propofol for at least for 20 minutes, blood was drawn and the propofol plasma concentration was measured. The predictive performance of Aquafol(TM) TCI was evaluated by determining the median performance error (MDPE), median absolute performance error (MDAPE), divergence, and wobble from the intra-individual and pooled performance errors. The acceptability of the TCI system was determined based on the pooled predictive performance. RESULTS: A total of 153 propofol blood samples were analyzed. The estimates of pooled MDPE, MDAPE, divergence and wobble were 8.59% (1.61), 19.1% (1.12), -1.12%/h and 9.87% (1.01), respectively. The MDAPE indicating the accuracy of the TCI infusion system was within the clinically acceptable range (< 20-30%) and the bias (MDPE) was also acceptable (< 10-20%). CONCLUSIONS: The performance of Aquafol(TM) TCI using a PION TCI(R) pump was acceptable for the clinical use.
Adult ; Anesthesia ; Anesthesia, General ; Bias (Epidemiology) ; Drug Delivery Systems ; Humans ; Mesons* ; Plasma ; Propofol

Ankylosing spondylitis is a chronic and systemic disease involving the axial skeleton. In patients with involved cervical spine ankylosing spondylitis, endotracheal intubation by direct laryngoscope may be difficult because they have a limitation of cervical movement and anatomical anomalies. We experienced the evaluation of thirteen patients with involved cervical spine ankylosing spondylitis by the Mallampati classification, Cormack and Lehane grade, thyromental distance and orolaryngeal angle. By Mallampati class and Cormack and Lehane grade, patients were almost class 3 or 4. Thyromental distance was 5.3 +/- 0.4 cm, and orolaryngeal angle was 90.4 +/- 8.0o.
Airway Management* ; Anesthesia* ; Classification ; Humans ; Intubation, Intratracheal ; Laryngoscopes ; Skeleton ; Spine* ; Spondylitis, Ankylosing*

BACKGROUND: Hydroxyethyl starches (HES) solutions are the most commonly used colloids for treating hypovolemia and expanding plasma, but they compromise platelet function and reduce the level of coagulation factors. As opposed to other HES solutions, 6% HES (130/0.4) solution may influence hemostasis minimally due to its low mean molecular weight and degree of substitution. This study was designed to establish the safety of HES (130/0.4) infusion in the presence of massive blood loss. METHODS: Twelve healthy adult patients scheduled for spine surgery were enrolled in this study. Before the induction of general anesthesia, all patients underwent acute normovolemic hemodilution (ANH), which was independent of surgical stress and other confounding factors. While approximately 30% of the estimated blood volume was procured, the blood deficit was replaced with the same volume of 6% HES (130/0.4) solution. Hematocrit, platelet count, factor VIII activity and plasma fibrinogen concentration were determined and thrombelastography was performed to evaluate the hemodilution effect and hemostatic impairment before and after ANH. Statistical testing was conducted to analyze the effect of HES on hemostasis. RESULTS: Hematocrit, platelet count, factor VIII activity and plasma fibrinogen concentrations decreased significantly (P < 0.05 respectively) after the ANH. On comparing pre-ANH and post-ANH thrombelastographic findings, the R time was shortened (P = 0.045), the alpha angle increased (P = 0.01) and MA decreased (P = 0.003) significantly. CONCLUSIONS: Summarizing, little effect was observed on the hemostatic system when 20 ml/kg of 6% HES (130/0.4) solution was infused. HES (130/0.4) solution as used to maintain normovolemia during ANH may be free from bleeding risk.
Adult ; Anesthesia, General ; Blood Coagulation Factors ; Blood Platelets ; Blood Volume ; Colloids ; Factor VIII ; Fibrinogen ; Hematocrit ; Hemodilution ; Hemorrhage ; Hemostasis* ; Humans ; Hypovolemia ; Molecular Weight ; Plasma ; Platelet Count ; Spine ; Starch ; Thrombelastography