BACKGROUND: Central nervous system dysfunction continues to be a major cause of morbidity after aorta and cardiac surgery under cardiopulmonary bypass (CPB). Pupillary reflexes are important component of the neurologic examination. The purpose of this study was to evaluate how the pupil reacts during hypothermic CPB under fentanyl anesthesia and its relation with postoperative neurologic deficits. METHODS: Fourteen patients undergoing ascending aortic dissection or aneurysm repair surgery under profound hypothermic CPB and circulatory arrest were enrolled. Pupil size and light reflex were evaluated at varying stages of CPB and temperatures. Temperatures were measured at different sites of perfusate, nasopharynx and rectum. Postoperatively neurologic assessments were performed to compare with the pupillary signs. RESULTS: Anesthetic induction with fentanyl decreased pupil size to pinpoint. Pupil dilated progressively under hypothermic CPB reaching fully dilated size at profound hypothermia. Rewarming returned the pupil to original size. Nasopharyngeal temperature correlated well with pupil size during cooling and rewarming. Light reflex was absent at any stage or temperature after anesthetic induction. Seven patients showed insignificant anisocoria and two died of other causes than neurologic deficit. One patient who was not in the anisocoria group exhibited delirium. CONCLUSIONS: Profound hypothermic CPB under fentanyl anesthesia dilates the pupil to a maximum size without light reflex overwhelming narcotic effect. Fully dilated pupil does not denote neurologic damage.
Anesthesia* ; Aneurysm ; Anisocoria ; Aorta ; Cardiopulmonary Bypass* ; Central Nervous System ; Delirium ; Fentanyl* ; Humans ; Hypothermia ; Narcotics ; Nasopharynx ; Neurologic Examination ; Neurologic Manifestations ; Pupil* ; Rectum ; Reflex ; Reflex, Pupillary ; Rewarming ; Thoracic Surgery

BACKGROUND: Controversy exists as to whether or not inhalation anesthetics and intravenous anesthetics impair arterial oxygenation (PaO2) during one lung ventilation (OLV). Accordingly, we examined the effect of enflurane and propofol on PaO2 and pulmonary vascular resistance (PVR) during OLV. METHODS: Forty patients, who had prolonged periods of OLV anesthesia with minimal trauma to the nonventilated lung were studied in a cross over design. Patients were randomized to four groups; Group 1 received 1 MAC of enflurane and oxygen from induction until the first 20 min after complete lung collapse, then were switched to propofol 100 g/kg/min (P100). In group 2, the order of the anesthetics was reversed. Group 3, Group 4 received the same order of the anesthetics as Group 1, Group 2, respectively but received propofol 200 g/kg/min (P200). RESULTS: During OLV, the PaO2 values were lower than those with two lung ventilation (TLV), there were no significant differences among each groups and between propofol and enflurane in PaO2, but in the selected patients (n=10, PaO2<120 mmHg during OLV), PaO2 in propofol group was higher than that of enflurane group (p<0.05). Conversion from TLV to OLV caused a significant increase in PVR, but there were no difference in PVR between propofol and enflurane group. CONCLUSIONS: These results suggest that the usual clinical dose of propofol affords no advantage over 1 MAC of enflurane anesthesia except low PaO2 patients during OLV. Propofol might be of value in risk patients of hypoxemia during thoracic surgery when OLV is planned.
Anesthesia ; Anesthetics ; Anesthetics, Inhalation ; Anesthetics, Intravenous ; Anoxia ; Cross-Over Studies ; Enflurane* ; Humans ; Lung ; One-Lung Ventilation* ; Oxygen* ; Propofol* ; Pulmonary Atelectasis ; Thoracic Surgery ; Vascular Resistance ; Ventilation

BACKGROUND: The implementation of intraoperative normovolemic hemodilution is a strategy used in an attempt to diminish the need for or obviate allogeneic transfusion and to avert the potential complications. The goal of this study was to evaluate the safety and efficacy of moderate intraoperative normovolemic hemodilution. METHODS: Fifteen patients scheduled for posterolateral spinal fusion underwent intraoperative normovolemic hemodilution with 10% pentastarch to a target hematocrit level of 25% (hemodilution group). All units of blood procured by hemodilution and additional allogeneic blood was transfused in the perioperative period to maintain the hematocrit level of>25%. We investigated the effect of hemodilution on whole blood coagulation as measured by the thromboelastography and, evaluated its efficacy of decreasing the need for allogeneic blood transfusion as compared to the nonhemodilution group, retrospectively. RESULTS: Hemodilution with pentastarch caused a decrease in response and coagulation time (p<0.01) but did not influence on the alpha angle and maximum amplitude on thromboelstogram. Amount of transfusion of allogeneic blood was 4.1 1.7 units for the hemodilution group and 5.0 1.5 units for the nonhemodilution group. Net red blood cell volume ""saved"" from hemodilution was about 120 ml. CONCLUSION: Moderate intraoperative normovolemic hemodilution with pentastarch does not affect the coagulability of whole blood. But its efficacy of decreasing the need for allogeneic blood transfusion is minimal.
Blood Coagulation ; Blood Transfusion ; Erythrocytes ; Hematocrit ; Hemodilution* ; Humans ; Hydroxyethyl Starch Derivatives ; Perioperative Period ; Retrospective Studies ; Spinal Fusion* ; Thrombelastography

BACKGROUND: The effect of arterial carbon dioxide tension (PaCO2) during ischemia and reperfusion has been a controversial issue. In this study, the effect of PaCO2 during ischemia and reperfusion was evaluated by 31P magnetic resonance spectroscopy (MRS). METHODS: Incomplete global cerebral ischemia was induced by ligation of carotid artery under lowered mean blood pressure (mean blood pressure= 40 mmHg) for 30 minutes followed by 2 hours of reperfusion. Eighteen cats were divided into 3 groups: For group 1 (n=6) (control group), animals were subjected to normocarbia (PaCO2=28~33 mmHg) during ischemia and reperfusion, for group 2 (n=6), animals were subjected to hypocarbia (PaCO2=18~23 mmHg) during ischemia and reperfusion, and for group 3 (n=6), animals were subjected to normocarbia during ischemia and hypocarbia during reperfusion. RESULTS: For group 1, the energy metabolism measured by [PCr/Pi] was recovered about 74.7 6.4%. For group 2, the energy metabolism failed to be completely recovered by 120 minutes of reperfusion (69.3 7.3%), whereas for group 3, the energy matabolism was completely recovered by 120 minutes of reperfusion (97.6 2.4%). There were statistically significant differences between group 1 and group 3 (p<0.05). The changes in pH were not significantly different among the groups. CONCLUSION: In this study, a condition of hypocarbia during reperfusion seems better for the energy metabolism after incomplete global ischemia of cats.
Animals ; Blood Pressure ; Brain Ischemia ; Brain* ; Carbon Dioxide ; Carotid Arteries ; Cats* ; Energy Metabolism* ; Hydrogen-Ion Concentration ; Ischemia ; Ligation ; Magnetic Resonance Spectroscopy ; Reperfusion

BACKGROUND: Phantom limb sensation is an unusual position sense of the extremity during nerve block that the position of extremity is misinterpreted as being flexed, or elevated, when actually they are in neutral position. Whether it is from the fixation of proprioceptive input at the time of motor blockade or from unmasking of the pattern which has been already present in the CNS is still controversial. We perfomed this study under the assumption that phantom limb sensation can still be reproduced without the influence of position at the time of nerve blockade. METHODS: Thirty-six patients scheduled for elective orthopedic surgery were randomly assigned. For 26 patients, spinal anesthesia was performed with hyperbaric 0.5% tetracaine or bupivacaine at lateral decubitus position and the position was changed to supine immediately. Existence of phantom limb sensation and the level of anesthesia was recorded at 10 and 20 minutes after injection of local anesthetics. For 10 patients, same local anesthetics were injected after patient's legs were straightened in lateral decubitus position. RESULTS: Forteen out of 26 patients whose position were changed to supine immediately after the injection of local anesthetics experienced phantom limb sensations. Five out of 10 patients whose legs were kept straight before the injection of local anesthetics experienced phantom limb sensations. Previous history of trauma was positively related to the expression of phantom limb sensation. CONCLUSION: Our data showed that the expression of phantom limb sensation is reproducible. And this was not related to the position at the time of spinal anesthesia. Trauma seems to be an important factor related to the expression of phantom limb sensation.
Anesthesia ; Anesthesia, Spinal* ; Anesthetics, Local ; Bupivacaine ; Extremities ; Humans ; Leg ; Nerve Block ; Orthopedics ; Phantom Limb* ; Proprioception ; Sensation* ; Tetracaine

BACKGROUND: The arterial to end-tidal carbon dioxide tension difference(Pa-ETCO2) can be increased in patients with congenital heart disease(CHD) and, therefore, end-tidal carbon dioxide tension(PETCO2) does not accurately approximates arterial carbon dioxide tension(PaCO2). The purpose of this study was to evaluate the stability of the Pa-ETCO2 in pediatric patients with congenital heart disease undergoing open heart surgery. METHODS: Forty three children with CHD were studied: twenty two were acyanotic and twenty one were cyanotic. Simultaneous PETCO2 and PaCO2 measurements, as well as pulse rate, blood pressure, pH and arterial oxygen tension(PaO2) were obtained for each patient during four intraoperative events: (1) after induction of anesthesia and before sternotomy, (2) after sternotomy and before cardiopulmonary bypass(CPB), (3) after weaning of CPB, and (4) after closure of sternotomy. RESULTS: The PETCO2 of cyanotic group were lower than that of acyanotic group throughout operation period, and did not change significantly after CPB. Cyanotic children demonstrated a greater Pa-ETCO2 difference before CPB as compared with acyanotic group. In acyanotic group, Pa-ETCO2 difference increased significantly after CPB(P <0.05), whereas it remained unchanged in cyanotic group. CONCLUSIONS: Since cyanotic children had higher Pa-ETCO2 differences intraoperatively and acyanotic children showed an increase in Pa-ETCO2 after CPB, the PETCO2 cannot be the alternative value to estimate reliably the PaCO2 during open heart surgery of pediatric CHD.
Anesthesia ; Blood Pressure ; Carbon Dioxide ; Child ; Heart Defects, Congenital ; Heart Diseases* ; Heart Rate ; Heart* ; Humans ; Hydrogen-Ion Concentration ; Oxygen ; Sternotomy ; Thoracic Surgery* ; Weaning

PURPOSE: To evaluate characteristic MR findings of primary cardiac and pericardiac tumors. MATERIALS AND METHODS: There were myxomas (n=7), malignant lymphoma (n=l), lipoma (n=l), and pericardiac mesotheliomas (n=2). We analyzed location, size, shape, signal intensity, contrast enhancement, and associated findings of adjacent structures such as pericardiac and pleural effusion, and mediastinal lymph node enlargement. RESULTS: Locations of the myxomas were left atrium in four cases, left ventricle in one, right atrium in one, and right ventricle in one. Mean diameter was 3.5cm (range, 2-7cm). They were polypoid or Iobulated in shape, and attached to interatrial or interventricular septurn in all cases except in right atrial myxoma which was attached to lateral wall. Their peduncles were demonstrated in three left atrial myxomas. The signal intensities were iso or slightly high on T1-weighted images and high on T2-weighted images. Pleural and pericardial effusions were shown in the three cases. Malignant lymphoma was manifested as large mass in right ventricle infiltrating to right atrium, interventricular septum, right paratracheal and retrocardiac area. It had slightly high intensity in both T1- and T2-weighted images with a strong contrast enhancement and associated with both pericardiac and pleural effusion. Lipoma was polypoid in shape and attached to lateral wall of left ventricle with bright T1 and high T2 signal intensity. Pericardiac mesothelioma was manifested as a pericardiac and atrial mass with diffuse irregular uneven thickening of pericardium which had iso signal on T1- and high T2-weighted images with moderate contrast enhancement. Conculsion: MR imaging is a very useful method in demonstration of the location, extent, tissue characteristics of the mass, and relationship with its adjacent structu res in evaluation of cardiac and pericardiac tumors.
Heart Atria ; Heart Ventricles ; Lipoma ; Lymph Nodes ; Lymphoma ; Magnetic Resonance Imaging* ; Mesothelioma ; Myxoma ; Pericardial Effusion ; Pericardium ; Pleural Effusion

BACKGROUND: Flow interruption technique has been used to measure respiratory system mechanics, and its prominent advantage is to partitionate the respiratory system resistance into airway and tissue component. In this study, we investigated the effects of varing concentrations of enflurane on respiratory system mechanics using flow interruption technique. METHODS: Six cats, weighing 3.0~3.6 kg were used. Pentobarbital sodium was injected intraperitonially and endotracheal intubation was followed. Intermittent mandatory ventilation was applied with Siemens Servo 900C ventilator. The inspiratory flow rate, tidal volume, and respiratory rate were fixed, and normocarbia (PaCO2; 30~35 mmHg) was maintained throughout the experiment. The changes in the pressure and volume were recorded with Bicore CP100 pulmonary monitor at control, 0.5, 1, 1.5, and 2 MAC of enflurane. The data were transfered to a PC and analyzed by Anadat processing software. Respiratory system, airway and tissue viscoelastic resistances, and dynamic and static compliances were calculated. RESULTS: Respiratory system resistances decreased up to 1 MAC of enflurane compared to the control value (p<0.05), but there were no significant differences in the values of resistance among 1, 1.5, 2 MAC of enflurane. There were no significant differences in tissue viscoelastic resistances, and dynamic and static compliances with varying concentrations of enflurane. CONCLUSIONS: Enflurane significantly reduces the respiratory system resistance mainly by decreasing airway resistance. Tissue viscoelastic resistance and respiratory system compliances are not influenced by changes in concentration of enflurane.
Airway Resistance ; Animals ; Cats* ; Enflurane* ; Intubation, Intratracheal ; Mechanics* ; Pentobarbital ; Respiratory Rate ; Respiratory System* ; Tidal Volume ; Ventilation ; Ventilators, Mechanical

Achondroplasia is a congenital disorder resulting from a specific disturbance in endochondral bone formation. The ophthalmic features reportedly associated with achondroplasia are telecanthus, exotropia, inferior oblique overaction, angle anomalies and cone-rod dystrophy. This is first report of chorioretinal coloboma in achondroplasia. An 8-year-old female was diagnosed with a developmental delay, known as achondroplasia, seven months after birth. Upon her initial visit, visual acuity was 0.3 in both eyes. The patient had telecanthus but normal ocular motility. Findings were normal upon anterior segment examination. Fundus examination of both eyes revealed about 1,500 microm sized chorioretinal coloboma inferior to the optic nerve head. Upon fluorescent angiography, there was chorioretinal coloboma without any other lesions. Afterward, there was no change in the fundus lesion, and best corrected visual acuity was 0.6 in both eyes. Chorioretinal coloboma is associated with choroidal and retinal detachment. As chorioretinal coloboma and achondroplasia are developmental disorders in the embryonic stage, early detection and regular ophthalmologic examination would be essential in patients with achondroplasia.
Achondroplasia/*complications/diagnosis ; Child ; Choroid/*abnormalities ; Choroid Diseases/*complications/diagnosis ; Coloboma/*complications/diagnosis ; Female ; Humans ; Ophthalmoscopes ; Tomography, Optical Coherence ; Visual Acuity

A pulmonary artery catheter (PAC) is a useful monitoring device for measuring pulmonary artery pressure, pulmonary capillary wedge pressure and cardiac output, but its insertion brings about many complications including pulmonary artery rupture, infarction, thrombosis and infection. This case concerns the knotting of a PAC in a 27 year-old female patient who had undergone cardiac transplantation due to dilated cardiomyopathy. The PAC was inserted via the right subclavian vein to the pulmonary artery and withdrawn to the superior vena cava before heart was removed. After the weaning of the cardiopulmonary bypass (CPB), we tried to reinsert the PAC, which was neither advanced nor withdrawn. Postoperative chest x-ray revealed that the PAC appeared to be knotted in the subclavian vein. Two days later, we loosened the knot of the PAC and removed it via femoral and bracheal cineangiography techniques guided by fluoroscopy without any complications. In this case, we thought the knotting of the PAC occurred at insertion due to severe tricuspid regurgitation, and its size was reduced at withdrawal before the CPB and wedging to the subclavian vein. Knotting of PAC is very rare and unpredictable, but once it or other complications of the PAC is suspected, we recommend that the manipulation of the PAC should be stopped and x-ray should be checked.
Adult ; Cardiac Output ; Cardiomyopathy, Dilated ; Cardiopulmonary Bypass ; Catheters* ; Cineangiography ; Female ; Fluoroscopy ; Heart ; Heart Transplantation* ; Humans ; Infarction ; Pulmonary Artery* ; Pulmonary Wedge Pressure ; Rupture ; Subclavian Vein ; Thorax ; Thrombosis ; Tricuspid Valve Insufficiency ; Vena Cava, Superior ; Weaning