Anesthetic experience performing intraoperative monitoring of motor evoked potentials during scoliosis surgery in adolescent patients: report on 7 cases: Seven cases report / 대한마취과학회지

Intraoperative monitoring of motor evoked potential (MEP) is a modality for preventing spinal cord injury during spinal surgery. However, inhalation anesthetics and muscle relaxants depressing MEP responses, must be restricted for monitoring MEP. Therefore, anesthetic management needs careful attention for preventing recall and unintentional movements during surgery and special techniques for monitoring adequate MEP. We report here on 7 cases of successful intraoperative monitoring of MEP with total intravenous anesthesia using propofol and remifentanil for scoliosis surgery in adolescent patients.

The effect of intraoperative colloid solutions coadministered with 6% hydroxyethyl starch (130/0.4) on platelet function in patients undergoing total intravenous anesthesia / 대한마취과학회지

BACKGROUND: Colloid solutions are used to treat hypovolemia and expanding plasma, but they may inhibit platelet function and reduce the level of coagulation factors during surgery. This study was conducted to compare the effects of hydroxyethyl starch (HES) on adenosine diphosphate (ADP)- and collagen-induced platelet aggregation in patients undergoing total intravenous anesthesia. METHODS: Patients undergoing endoscopic sinus surgery under total intravenous anesthesia with propofol and remifentanil were divided into a group that underwent fluid management with only crystalloid solution (n = 15) and a group that was managed with crystalloid solution that included 6% HES (130/0.4) (n = 15). ADP- and collagen-induced platelet aggregation were measured 5 minutes before induction, after the first intraoperative hour, and one hour postoperatively. RESULTS: Significantly diminished ADP- and collagen-induced aggregation values were observed intraoperatively when compared with the preoperative value in the patients that were managed with colloid solution that included HES. In addition, significantly diminished collagen-induced aggregation values were observed intraoperatively when compared with the preoperative value in the group that was managed with the solution that only contained the crystalloid. However, ADP- and collagen-induced platelet aggregation were recovered postoperatively in both groups. CONCLUSIONS: The results of this study indicated that fluid therapy with colloid solution that contained 6% HES (130/0.4) may diminish ADP-induced platelet aggregation intraoperatively in patients subjected to total intravenous anesthesia.

Effects of sevoflurane and desflurane on respiratory mechanics after tracheal intubation in children / 대한마취과학회지

BACKGROUND: Tracheal intubation causes a reflex tracheal constriction that leads to increased airway resistance. Inhalation anesthetics can prevent or minimize this response. Therefore, this study was conducted to evaluate the effect of 1 MAC sevoflurane or desflurane on respiratory mechanics in children after anesthetic induction using propofol and tracheal intubation. METHODS: Sixty children undergoing elective surgery with tracheal intubation were assigned into two groups at random, a 1 MAC concentration of sevoflurane (n = 30) and a desflurane (n = 30) group. Anesthesia was induced using propofol (1.5 mg/kg) and tracheal intubation was facilitated using rocuronium (0.6 mg/kg). A respiratory profile monitor was used to measure the respiratory resistance, dynamic compliance and peak inspiratory airway pressure. The measurements were made at three time points, after three inspirations from the beginning of mechanical ventilation (baseline) and at 5 and 10 min after the administration of inhalation anesthetics. RESULTS: Sevoflurane and desflurane led to a significant decrease in respiratory resistance and increased dynamic compliance at 5 and 10 min when compared to baseline. There were no significant differences in respiratory resistance and dynamic compliance between the two groups. CONCLUSIONS: A 1 MAC concentration of sevoflurane and desflurane has a similar bronchodilatory effect after tracheal intubation in children.

Experiences of the Total Intravenous Anesthesia with Remifentanil in High-risk Preterm Infants: A case report / 대한마취과학회지

Advances in neonatal medicine have improved survival rate of preterm infants, but also increased incidence of painful intensive care such as various surgical procedures and mechanical ventilation. Anesthesiologists face many problems related to their prematurity during anesthesia. So they must make plans for anesthesia carefully. Remifentanil is a useful opioid for preterm infants because of it's unique pharmacokinetic properties, minimally altered by extremes of age or renal or hepatic dysfunction, a sparing effect of hypnotics and sedatives, and provision of optimal intraoperative analgesia without compromising recovery time.We describe the successful use of the total intravenous anesthesia with remifentanil in three preterm infants undergoing thoracic and abdominal surgery.

The Effects of Propofol-remifentanil Total Intravenous Anesthesia on Platelet Function / 대한마취과학회지

BACKGROUND: The majority of anesthetic agents, including inhalation anesthetics, inhibit platelet function, but the effect of propofol on platelets is controversial. This study was designed to compare the effects of propofol-remifentanil total intravenous anesthesia and sevoflurane inhalation anesthesia on platelet function. METHODS: Patients undergoing major hip surgery were divided into two groups: inhalation anesthesia with sevoflurane or total intravenous anesthesia with propofol and remifentanil. Hemoglobin, hematocrit, platelet count, prothrombin time, activated partial thromboplastin time, and platelet aggregation were measured 5 minutes before induction, the first hour intra-operatively, and the first hour postoperatively. RESULTS: Total intravenous anesthesia with propofol and remifentanil significantly diminished collagen-induced platelet aggregation values intraoperatively compared with preoperative values. Also, intraoperative collagen- and adenosine diphosphate (ADP)-induced platelet aggregation was significantly lower in anesthesia with propofol and remifentanil compared with sevoflurane anesthesia.Sevoflurane did not induce significant changes in collagen- or ADP-induced platelet aggregation. CONCLUSIONS: Total intravenous anesthesia with propofol and remifentanil significantly reduced collagen-induced platelet aggregation intraoperatively, while inhalation anesthesia with sevoflurane did not reduce collagen-or ADP-induced platelet aggregation at all.

Comparing the effects of esmolol and remifentanil on the cardiovascular and catecholamine response to endotracheal intubation during the induction of general anesthesia / 대한마취과학회지

BACKGROUND: Esmolol and remifentanil are widely used drugs that minimize the increase of the blood pressure and the heart rate in response to endotracheal intubation during the induction of anesthesia. The purpose of this study is to compare the effect of esmolol and remifentanil on the cardiovascular and catecholamine responses to endotracheal intubation. METHODS: Sixty ASA I and II patients were randomly allocated to three groups. Anesthesia was induced with propofol 2 mg/kg and rocuronium 0.9 mg/kg and this was maintained with 2 vol% sevoflurane and 50% nitrous oxide in oxygen. The patients received 10 ml intravenous saline (control group), 1.5 mg/kg esmolol (esmolol group) or 1microgram/kg remifentanil followed by an infusion of 0.1microgram/kg/min (remifentanil group) before intubation. The noninvasive blood pressure and heart rate were recorded before induction (baseline), before intubation and at 1, 2, 3 and 5 minutes after intubation. The blood catecholamine level (epinephrine and norepinephrine) was measured before induction and at 1 and 5 minutes after intubation. RESULTS: The systolic, diastolic and mean arterial pressures after endotracheal intubation were similar in the control and esmolol groups, but they were lower in the remifentanil group (P 0.05). CONCLUSIONS: 1microgram/kg remifentanil followed by an infusion of 0.1microgram/kg/min is more effective than 1.5 mg/kg esmolol for inhibiting the cardiovascular responses following endotrachal intubation during the induction of general anesthesia.

Comparing the effects of esmolol and remifentanil on the cardiovascular and catecholamine response to endotracheal intubation during the induction of general anesthesia / 대한마취과학회지

BACKGROUND: Esmolol and remifentanil are widely used drugs that minimize the increase of the blood pressure and the heart rate in response to endotracheal intubation during the induction of anesthesia. The purpose of this study is to compare the effect of esmolol and remifentanil on the cardiovascular and catecholamine responses to endotracheal intubation. METHODS: Sixty ASA I and II patients were randomly allocated to three groups. Anesthesia was induced with propofol 2 mg/kg and rocuronium 0.9 mg/kg and this was maintained with 2 vol% sevoflurane and 50% nitrous oxide in oxygen. The patients received 10 ml intravenous saline (control group), 1.5 mg/kg esmolol (esmolol group) or 1microgram/kg remifentanil followed by an infusion of 0.1microgram/kg/min (remifentanil group) before intubation. The noninvasive blood pressure and heart rate were recorded before induction (baseline), before intubation and at 1, 2, 3 and 5 minutes after intubation. The blood catecholamine level (epinephrine and norepinephrine) was measured before induction and at 1 and 5 minutes after intubation. RESULTS: The systolic, diastolic and mean arterial pressures after endotracheal intubation were similar in the control and esmolol groups, but they were lower in the remifentanil group (P 0.05). CONCLUSIONS: 1microgram/kg remifentanil followed by an infusion of 0.1microgram/kg/min is more effective than 1.5 mg/kg esmolol for inhibiting the cardiovascular responses following endotrachal intubation during the induction of general anesthesia.

Pressure sore after Cesarean section under epidural anesthesia and analgesia: Two cases report / 대한마취과학회지

Epidural anesthesia and analgesia provide a better outcome after major surgery. Several complications such as hypotension, motor block and dural puncture are well known. Epidural anesthesia and analgesia may also cause pressures sore in elderly and debilitated patients. Prolonged soft tissue compression results in discomfort and pain secondary to local ischemia in normal individuals. The presence of hypotension, hypothermia and the interruption of venous or lymphatic drainage of the lower extremities, as well as the lack of frequent repositioning, are all contributing factors to the development of pressure sore. We describe a pressure sore that occurred in two young and healthy parturients after epidural anesthesia and analgesia.

The Successful Anesthetic Management ofCesarean Section for Quadruplets: A case report / 대한마취과학회지

Grand multifetal pregnancies (4 or more), usually caused by ovulation induction agents and assisted reproductive technologies, challenge all members of a perinatal team and put mothers and infants increased risk. Important anesthetic considerations include greater incidence of complications that in the singleton pregnancy, risks related to the large pregnant uterus, impaired uterine contraction prior to delivery secondary to fetal oxygenation, and preparation of sufficient man-power and instruments. The importance of neonatal resuscitation cannot be overemphasized. We report a successful general anesthetic management for an emergent quadruplet cesarean section at 31 weeks 5 days weeks gestational age.

Comparison of the Effects of Propofol and Ketamine on Respiratory Mechanics during Anesthetic Induction in Children / 대한마취과학회지

BACKGROUND: Propofol and ketamine are believed to reduce airway resistance. The aim of the present study was to compare the effect of propofol and ketamine on respiratory mechanics after endotracheal intubation in children. METHODS: Forty pediatric patients were assigned randomly to two groups: propofol (n = 20) and ketamine (n = 20). Patients were anesthetized with propofol (2 mg/kg) or ketamine (2 mg/kg). All patients were paralyzed with rocuronium (0.8 mg/kg) and intubated and ventilated mechanically (ETCO2: 30-40 mmHg, tidal volume: 10 ml/kg, respiratory rate: 15-25 time/min). Peak inspiratory pressure (PIP), respiratory resistance (Rr), dynamic compliance (Cdyn) and expiratory tidal volume (Vte) measurements were recorded at five time points; 0.5 min after intubation without sevoflurane (baseline), following 2.5 min, 5 min, 7.5 min and 10 min of ventilation with 2% sevoflurane- 50% nitrous oxide. RESULTS: Rr at 0.5 min after intubation was 27.4 +/- 12.7 cmH2O/L/s in the propofol group, and 30.0 +/- 13.5 cmH2O/L/s in the ketamine group. Cdyn at 0.5 min after intubation was 28.0 +/- 9.9 ml/cmH2O in the propofol group, and 25.1 +/- 10.6 ml/cmH2O in the ketamine group. There was no significant difference in the response of PIP, Rr, Cdyn and Vte between two groups and within groups. CONCLUSIONS: We suggest that the effects of propofol and ketamine on respiratory mechanics were similar during anesthetic induction in children.

General Anesthesia in a Patient with Infantile Pompe's Disease : A case report

Pompe's disease (type II glycogen storage disease) is an autosomalrecessive disorder caused by a deficiency of lysosomal acid alpha- glucosidase (GAA) leading to the accumulation of glycogen in the lysosomes primarily in cardiac and skeletal muscle. Recently a promising enzyme replacement therapy has resulted in improved clinical outcomes and a resurgence of elective anesthesia for these patients. The anesthetic management of infant with Pompe's disease presents a variety of challenges. Therefore, understanding the unique cardiac and respiratory physiology is essential to providing safe general anesthesia. We report a case of patient with infantile-onset Pompe's disease who underwent a tracheostomy for a ventilator care.

Temperature Changes and Shivering during Epidural Anesthesia in Women Undergoing Cesarian Delivery / 대한마취과학회지

BACKGROUND: Epidural anesthesia decreases the core temperature triggering vasoconstriction and shivering, presumably by increasing apparent lower-body temperature. We therefore tested the hypothesis that epidural anesthesia in cesarian delivery patients decrease forearm-fingertip skin-surface temperature gradient and it is cause of shivering. METHODS: Twenty-two healthy pregnant women were studied. Epidural anesthesia was induced by 2% lidocaine and 0.75% ropivacaine 24 ml (T4 level) at 25degrees C ambient temperature. Shivering were evaluated by observation. Core temperature was recorded in the external auditory canal using a compensated infrared thermometer. Arteriovenous shunt tone was evaluated with forearm- fingertip temperature gradients; gradients less than 0 were considered evidence of vasodilation. Skin-surface temperature, skin- temperature gradients (forearm-fingertip, calf-toe) and the presence or absence of shivering were measured. RESULTS: Shivering was observed in seven of twenty two patients. Sixty minutes after induction, Tympanic temperature decreased for 0.8 +/- 0.1degrees C in non-shivering patients and 0.9 +/- 0.1degrees C in shivering patients. Forearm temperature decreased for 0.2 +/- 1.7degrees C in non-shivering patients, but increased for 0.5 +/- 0.6degrees C in shivering patients. Upper limb (Forearm-fingertip) skin Temperature gradients continues the plus in non-shivering patients, but maintain minus (45 minutes after induction) in shivering patients. Low limb skin temperature is increases in both group. CONCLUSION: We failed to confirm our hypothesis, but for an expected reason: shivering was preceded by hypothermia and vasoconstriction in the arm. For prevention of hypothermia in epidural anesthesia, not to be monitored core temperature, but also upper limb skin temperature gradients.

Effects of Low Dose Propofol on Core and Peripheral Temperatures during Spinal Anesthesia / 대한마취과학회지

BACKGROUND: Core hypothermia during the first hour after induction of anesthesia results primarily from a redistribution of body heat. Propofol in low doses provides reliable sedation and is associated with fast recovery. However, propofol-induced peripheral vasodilation is likely to facilitate core-to-peripheral heat redistribution. This study was designed to evaluate the effects of low dose propofol on core and peripheral temperatures during spinal anesthesia. METHODS: Fifty patients of ASA status I or II, aged 20 to 60, undergoing lower extremity surgery under spinal anesthesia were studied. Spinal anesthesia was administered to all patients, who were assigned sedation as follows: 1) control (n = 25), 2) propofol (n = 25); propofol infusion rates were, 8 mg/kg/h for the first 3 min, 4 mg/kg/h for the next 10 min, and 2 mg/kg/h for the next 15 min. Temperatures were recorded after beginning surgery at 5-min intervals for 30 min. RESULTS: Core temperature was significantly decreased after 15, 20, 30 min of surgery in the propofol group, and this result was statistically different between the two groups. Forearm skin temperature decreased in the control group and increased in the propofol group, without significance. Fingertip skin temperature did not changed significantly in the control group, but increased significantly after 15 min in the propofol group and continued to increasing to 30 min. Forearm minus finger skin temperature gradients were not changed significantly in control group, but decreased between 5 and 30 min in the propofol group, which was statistically significant. CONCLUSIONS: Low dose propofol may induce a degree of hypothermia during spinal anesthesia. Close monitoring is needed to prevent core hypothermia, if sedation is induced using propofol during spinal anesthesia.

Fluid Management in Kidney Transplantation: Central Venous Pressure Guided vs Esophageal Doppler Monitoring / 대한마취과학회지

BACKGROUND: Maximizing renal blood flow during reperfusion of the transplanted kidney could be the key factor to prevent acute tubular necrosis (ATN). To achieve such a goal, augmentation of circulating blood volume is necessary. We evaluated stroke volume monitored or CVP guided volume expansion method and, which method would be better for the outcome. METHODS: Forty three patients (Group I) of 79 patients received maximum hydration guided by CVP maintaining 12-15 mmHg, other 36 patients (Group II) received fluid to achieve maximum SV using esophageal doppler monitor. All patients received albumin (maximal dose < 1 g/kg), mannitol (20%, 200 ml), and furosemide (40 mg) before renal artery reperfusion. Postoperative tests for evaluation of renal function, incidence of ATN and morbidity and hospital stay in patient were investigated. RESULTS: Amount of fluid infused were 3,891 +/- 1,145 ml in Group I and 2,981 +/- 936.4 ml in Group II. Incidence of ATN (Group I; 9.3% and Group II; 8.3%), tests for renal function were not statistically significant in both Group, but two patients in Group I was administered in intensive care unit (ICU). CONCLUSIONS: Lesser fluid was administered in the Group used with SV augmentation than conventional CVP guided group and there was no difference in the incidence of ATN between two group. In kidney transplantation, esophageal doppler monitoring may be better in fluid management than CVP monitoring.

Comparison of ETT and LMA on Respiratory Mechanics during the Induction of General Anesthesia in Children / 대한마취과학회지

BACKGROUND: Laryngeal mask airway (LMA) has recently been introduced as an alternative for the endotracheal tube. The respiratory mechanics and respiratory parameters during positive pressure ventilation (PPV) via the laryngeal mask airway (LMA) are not well known in children. So, we compared the effects of the endotracheal tube and the laryngeal mask airway on respiratory mechanics during the induction of general anesthesia in children. METHODS: We studied sixty ASA physical status I and II healthy children undergoing general anesthesia. Anesthesia was induced with sleep dose ketamine 1.0 mg/kg i.v., supplemented with propofol 2 mg/kg, Rocuronium 1.0 mg/kg i.v and maintained with 50% nitrous oxide and 2.0 Vol% sevoflurane. After inserting the laryngeal mask airway, its cuff was inflated using a balloon cuff gauge until the intracuff pressure reached approximately 60 cmH2O. Adequacy of ventilation was assessed by observing the end tidal carbon dioxide wave form, chest wall movement, and by stethoscope auscultation. Data were collected with lung mechanics recorders (Ventcheck, Novametrix Medical System, U.S.) at 5 and 10 minutes after intubation or LMA insertion. The data included Peak Inspiratory Pressure (PIP), Mean Airway Pressure (MAP), Peak End Expiratory Pressure (PEEP), Inspired Tidal Volume (VTins), Expired Tidal Volume (VTexp), Airway resistance (Raw), and Compliance (Cdyn). RESULTS: No significant difference was observed between the airway pressures, tidal volumes and gas leak fractions of the ETT and LMA groups. In terms of airway resistance and compliance, significant differences were observed between the two groups at 5 and 10 minutes. CONCLUSIONS: We conclude that the laryngeal mask airway is superior to endotracheal intubation in terms of airway resistance and compliance. The laryngeal mask airway offer an alternative for the children needing to avoid intubation under general anesthesia.

Core Temperature and Skin-Surface Temperature Gradients of Ketamine and Propofol for Anesthetic Induction in Children / 대한마취과학회지

BACKGROUND: Hypothermia after induction of anesthesia results initially from core-to-peripheral redistribution of body heat. Both central inhibition of tonic thermoregulatory vasoconstriction in arteriovenous shunts and anesthetic induced vasodilation contribute to core-to-peripheral redistribution of heat. Ketamine increases peripheral arteriolar resistance uniquely; in contrast, propofol causes profound venodilatation that other anesthetics do not. The aim of the present study is to evaluate core temperature and skin-surface temperature gradients in use of ketamine for anesthetic induction compared with propofol in children. METHODS: Forty pediatric patients of ASA status I or II, undergoing elective surgery for strabismus or inguinal hernia were studied. The patients were allocated randomly to one of two groups: (i) GROUP P (n = 20): Anesthesia was induced with propofol and maintained with sevoflurane in combination with 60% nitrous oxide in oxygen. (ii) GROUP K (n = 20): Anesthesia was induced with ketamine and maintained with sevoflurane in combination with 60% nitrous oxide in oxygen. Core temperature, forearm skin temperature, fingertip skin temperature and Forearm minus fingertip, skin-temperature gradients were recorded before induction of anesthesia, 3 min after administering ketamine or propofol (just before endotracheal intubation), 5 min, and at 5-min intervals after induction of anesthesia. RESULTS: After induction of anesthesia, core temperature in the two groups was decreased but results did not differ significantly between two groups. Forearm skin temperature was increased significantly after 20 min of anesthesia in propofol group and 15 min of anesthesia in ketamine group, but results did not differ significantly between two groups. Finger tip skin temperature was increased significantly after 3 min of anesthesia in the propofol group and 10 min of anesthesia in the ketamine group. Finger tip skin temperature of 5 min of anesthesia in propofol group increased significantly greater than in ketamine group. Forearm minus finger skin surface temperature gradients was decreased statistically significantly at 3 min of anesthesia in the propofol group and 10 min of anesthesia in the ketamine group, gradients of 5 min of anesthesia was presented statistically significant between two groups. CONCLUSIONS: For pediatric patients, after induction of anesthesia with ketamine arteriovenous shunt vasomoter status was well maintained. And maintaining vasoconstriction during induction of anesthesia reduced the magnitude of redistribution hypothermia.

The Effects of an Epinephrine-containing Epidural Test Dose during Epidural Anesthesia on Ropivacaine / 대한마취과학회지

BACKGROUND: Epinephrine-containing epidural test dose is used for obstetric epidural anesthesia to identify the unintentional cannulation of an epidural vessel. This study evaluated the effects of an epinephrine test dose during epidural anesthesia with 0.5% ropivacaine in ceasrean section. METHODS: Seventy healthy pregnant women, scheduled for elective cesarean section were randomly assigned to one of two groups. A lumbar epidural catheter was placed and aspirated. If aspiration was positive for blood or cerebrospinal fluid, the catheter was replaced. All patients received an 3 ml test dose of either 1.5% lidocaine with epinephrine 5microgram/ml (group E) or lidocaine only (group C). After test dose, 50microgram fentanyl and 20 ml of 0.5% ropivacaine were given to the all patients. Applying the pin prick method and a modified Bromage scoring system, senseory block level and motot block intensity were checked at 5 min intervals for the first hour following ropivacaine injection. After then, they were checked at 15 min intervals for the rest of the test period. Heart rate (HR) and blood pressure (BP) were measured as well. RESULTS: No significant difference between the two groups was detected in HR, BP, the profile of sensory block, motor scores and the onset of motor block. However, group C showed significantly shorter span of motor block (102 +/- 31 min.) than group E (134 +/- 32 min.) (P <0.05). There was no significant difference in neonatal outcome, as assessed by Apgar score at delivery. The most common adverse effect in mothers was hypotension. No serious adverse effects were detected in this study. CONCLUSIONS: We conclude that only the span of motor block by the epidural ropivacaine is affected by epinephrine-containing epidural test dose.

Myoclonic and Tonic-Clonic Seizures after Propofol Sedation during a Brachial Plexus Block: A case report / 대한마취과학회지

Propofol has become a popular intravenous agent for the induction and maintenance of total intravenous anesthesia (TIVA). However, the pro- or anticonvulsant properties of propofol remain controversial and abnormal muscle movement and convulsive activity are possible side-effects. We report a case in which a healthy 42-year-old man developed myoclonic and tonic-clonic seizures related to the use of propofol for sedation during a brachial plexus block.

Myoclonic and Tonic-Clonic Seizures after Propofol Sedation during a Brachial Plexus Block: A case report / 대한마취과학회지

Propofol has become a popular intravenous agent for the induction and maintenance of total intravenous anesthesia (TIVA). However, the pro- or anticonvulsant properties of propofol remain controversial and abnormal muscle movement and convulsive activity are possible side-effects. We report a case in which a healthy 42-year-old man developed myoclonic and tonic-clonic seizures related to the use of propofol for sedation during a brachial plexus block.

Effects of K+ Channel Opener WAY120491 on Renal Function in Rabbits / 대한신장학회잡지

BACKGROUND: K+ channel opener has been considered as a vasorelaxing agent working through hyperpolarization of vascular smooth muscle cells. Renal tubules-proximal, thick ascending limb of Henle and cortical collecting duct-are the site of the diversity of the K+ channel. ATP-sensitive K+ channel has been observed in the apical membranes of the thick ascending limb of Henle and collecting duct, and basolateral membrane of the proximal tubule. It was also shown that K+ channel opener increased renal hemodynamics and elicited diuretic and natriuretic effects. METHODS: To clarify the renal effects of WAY120491, a K+ channel opener, experiments were performed in unanesthetized normotensive and renal hypertensive rabbits allowing unilateral renal arterial infusion of agent. RESULTS: Intrarenal arterial infusion (0.13, 0.32 and 0.64 microgram/kg/min) of WAY120491 increaased CPAH, CCr, urine volume, UNaV, UKV and CH2O. Renal hemodynamic effects and increments of urine volume and free water clearance were completely blocked by glibenclamide (8.2 g/kg/min), while increments of UNaV and FENa were not significantly affected. Renal hemodynamic and tubular effects of WAY120491 were not significantly different in two-kidney one clip Goldblatt hypertensive rabbits from sham-operated rabbits. CONCLUSIONS: These results suggest that WAY120491 elicits renal effects through ATP-sensitive K+ channel in the renal vasculatures and renal tubules and the renal effects of WAT120491 may not be altered in the hypertension.