RESUMEN
BACKGROUND: Endotracheal intubation in patients with compromised cervical vertebrae and limited mouth opening is challenging, however, there are still limited options available. Among devices used for managing difficult airways, the Clarus Video System (CVS) might have considerable promise due to its semi-rigid tip. We evaluated the performance of CVS in patients with simulated difficult airways. METHODS: Philadelphia cervical collars were applied to 74 patients undergoing general anesthesia. The degree of simulated difficult airway was assessed by observing laryngeal view using McCoy laryngoscope; modified Cormack and Lehane grade (MCL) ≥ 3a (high-grade group, n = 38) or ≤ 2b (low-grade group, n = 36). Subsequently, patients were intubated using CVS by a blinded practitioner. We evaluated total time to intubation, intubation success rate, and conditions of intubation. RESULTS: Intubation took significantly longer time for the high-grade group than that for the low-grade group (38.2 ± 25.9 seconds vs. 27.9 ± 6.2 seconds, time difference 10.3 seconds, 95% confidence interval: 1.4–19.2 seconds, P < 0.001). However, CVS provided similar high intubation success rates for both groups (97.4% for the high-grade and 100% for the low-grade group). During intubation, visualization of vocal cords and advancement into the glottis for the high-grade group were significantly more difficult than those for the low-grade group. CONCLUSIONS: Although intubation took longer for patients with higher MCL laryngeal view grade, CVS provided high intubation success rate for patients with severely restricted neck motion and mouth opening regardless of its MCL laryngeal view grade.
Asunto(s)
Femenino , Humanos , Anestesia General , Vértebras Cervicales , Glotis , Intubación , Intubación Intratraqueal , Laringoscopios , Boca , Cuello , Pliegues VocalesRESUMEN
The most frequent perioperative cardiovascular event is cardiac dysrhythmia, defined as an abnormality of cardiac rate, rhythm or conduction. Although the occurrence of arrhythmia during the perioperative period is not uncommon, a case of newly developed perioperative atrial flutter which spontaneously converts to atrial fibrillation is rare. We report a case of atrial flutter that developed immediately after induction of general anesthesia, in a 70-year-old male patient who previously had a normal sinus rhythm. Atrial flutter changed spontaneously to atrial fibrillation after discharge to the recovery room. Dysrhythmia was unresponsive to drug therapy, and the atrial fibrillation disappeared after electric cardioversion.
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Anciano , Humanos , Masculino , Anestesia General , Arritmias Cardíacas , Fibrilación Atrial , Aleteo Atrial , Quimioterapia , Cardioversión Eléctrica , Periodo Perioperatorio , Sala de RecuperaciónRESUMEN
Horner syndrome is characterized by miosis, partial blepharoptosis and anhidrosis on the affected side of the face. This syndrome develops when the oculosympathetic nerve pathways to the eye and face are interrupted by various causes such as tumor in the brain, intrathoracic region or neck, surgery, drugs, trauma, carotid artery dissection, and others. It is referred to as painful Horner syndrome when Horner syndrome is accompanied by hemifacial pain. Pain is probably related to trigeminal nerve injury. Horner syndrome is a rare complication of thyroidectomy. Here, we report the case of a patient who experienced ipsilateral painful Horner syndrome after total thyroidectomy and unilateral neck dissection for thyroid cancer.
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Humanos , Blefaroptosis , Encéfalo , Traumatismos de las Arterias Carótidas , Síndrome de Horner , Hipohidrosis , Miosis , Cuello , Disección del Cuello , Neoplasias de la Tiroides , Tiroidectomía , Traumatismos del Nervio TrigéminoRESUMEN
BACKGROUND: The ideal alternative airway device should be intuitive to use, yielding proficiency after only a few trials. The Clarus Video System (CVS) is a novel optical stylet with a semi-rigid tip; however, the learning curve and associated orodental trauma are poorly understood. METHODS: Two novice practitioners with no CVS experience performed 30 intubations each. Each trial was divided into learning (first 10 intubations) and standard phases (remaining 20 intubations). Total time to achieve successful intubation, number of intubation attempts, ease of use, and orodental trauma were recorded. RESULTS: Intubation was successful in all patients. In 51 patients (85%), intubation was accomplished in the first attempt. Nine patients required two or three intubation attempts; six were with the first 10 patients. Learning and standard phases differed significantly in terms of success at first attempt, number of attempts, and intubation time (70% vs. 93%, 1.4 ± 0.7 vs. 1.1 ± 0.3, and 71.4 ± 92.3 s vs. 24.6 ± 21.9 s, respectively). The first five patients required longer intubation times than the subsequent five patients (106.8 ± 120.3 s vs. 36.0 ± 26.8 s); however, the number of attempts was similar. Sequential subgroups of five patients in the standard phase did not differ in the number of attempts or intubation time. Dental trauma, lip laceration, or mucosal bleeding were absent. CONCLUSIONS: Ten intubations are sufficient to learn CVS utilization properly without causing any orodental trauma. A relatively small number of experiences are required in the learning curve compared with other devices.
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Humanos , Educación , Hemorragia , Intubación , Intubación Intratraqueal , Laceraciones , Curva de Aprendizaje , Aprendizaje , LabioRESUMEN
BACKGROUND: The aim of this study is to evaluate the status and adverse events of anesthesiologist-administered sedation and general anesthesia, outside of the operating room. METHODS: Patients undergoing sedation and general anesthesia, outside of the operating room, were retrospectively reviewed, during the study period from March to October of 2011. The patient's characteristics, primary diagnosis for the procedure, procedures performed outside of the operating room, adverse events associated with sedation and anesthesia, sedatives/anesthetic agents, and anesthetic time, were all assessed. RESULTS: A total of 429 patient's submitted data on 44 sedation/401 general anesthesia were encountered, during the study period. The range of age varied from 2 months to 83 yrs. Most common primary diagnosis for the procedure, during sedation or general anesthesia, was vascular or neurologic problem, respectively. The most frequently used sedatives or analgesics were propofol alone, during sedation (45%) and propofol with remifentanil, during general anesthesia (60%), respectively. Adverse events occurred in 32%, during sedation and 29%, during general anesthesia. Bradycardia occurred in 16% of sedation and hypotension occurred in 15% of general anesthesia. CONCLUSIONS: Our data suggest that the sedation/general anesthesia for procedures, outside of the operating room, have been performed in a complex situation, various location, and wide age groups. Adequate monitoring, sufficient anesthesia support, including skilled staff and emergency equipments, and appropriate drug for each procedure are needed for the patient's safety.
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Humanos , Analgésicos , Anestesia , Anestesia General , Bradicardia , Urgencias Médicas , Hipnóticos y Sedantes , Hipotensión , Quirófanos , Piperidinas , Propofol , Estudios RetrospectivosRESUMEN
Azygous vein aneurysm is a rare congenital lesion that needs to be differentiated from mediastinal mass lesions. Although almost of these anomalies are asymptomatic lesions, we experienced an interesting case in which a thrombus within an azygous vein aneurysm in a 75-year-old woman caused pulmonary thromboembolism. The patient was managed by medical treatment for one month and then the thrombus within both the azygous vein aneurysm and the pulmonary arteries completely resolved.
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Anciano , Femenino , Humanos , Aneurisma/complicaciones , Vena Ácigos , Técnicas de Imagen Sincronizada Cardíacas , Tomografía Computarizada Multidetector , Embolia Pulmonar/etiología , Trombosis/complicacionesRESUMEN
Indigo carmine has been used for eight decades with few adverse effects. Several of our patients, however, experienced severe hypotensive episodes after indigo carmine administration within a period of one month. Analysis of the raw materials used to formulate the preparation of indigo carmine we used showed that they contained impurities. Following recall of these impure materials, none of our patients experienced further hypotensive episodes.
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Humanos , Hipotensión , Carmin de Índigo , IndolesRESUMEN
PURPOSE: This study was designed to determine whether transabdominal ultrasound can detect different hepatic stiffness between patients with cirrhosis and control subjects. MATERIALS AND METHODS: Sevent-three patients (Child-Pugh class A stage) with liver cirrhosis and 57 control subjects were included in this study. All patients were subdivided arbitrarily into two groups: early cirrhosis (n = 53) and overt cirrhosis (n = 20). Two sagittal images of the left lobe of the liver were obtained in the left hepatic vein level during the resting state and at full inspiration while pushing their belly out, by abdominal US (i.e., resting and stress image). The length between the inferior hepatic angle and the midpoint of the liver dome was measured in all images for the evaluation of liver distortion. The elongation was calculated by a formula: (L2-L1/L1) x 100(%); where L1 and L2 are the length of the liver for both the resting and stress image. The calculated elongated length (L2-L1, EL) and elongation rate were compared between cirrhotic patients and control subjects. RESULTS: For the control subjects, early cirrhosis, and overt cirrhosis groups, the mean ELs (elongation rate) were 2.34+/-0.98 cm (30.2+/-13.2%), 1.18+/-0.73 cm (14.9+/-9.5%) and 0.53+/-0.54 cm (6.3+/-6.6%), respectively. This difference among the three groups was statistically significant (p < 0.05). A possible best cut-off value of liver elongation rate is 17% for the prediction of cirrhosis (sensitivity: 90%, specificity: 75.3%). CONCLUSION: The liver of patients with liver cirrhosis is stiffer than that of control subjects. Calculation of the elongation rate in the left lobe of the liver during a respiratory maneuver may be used as an ancillary method of US for the evaluation of liver cirrhosis.
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Humanos , Fibrosis , Venas Hepáticas , Hígado , Cirrosis Hepática , RespiraciónRESUMEN
A 38-year-old woman who had undergone pelvic lymphangioma resection two months previously presented with cough and dyspnea. Transthoracic echocardiography and CT demonstrated the presence of a mixed cystic/solid component tumor involving the inferior vena cava, heart and pulmonary artery. Complete resection of the cardiac tumor was performed and lymphangioma was confirmed based on histopathologic examination. To the best of our knowledge, this is the first report of lymphangiomatosis with cardiac and pelvic involvement in the published clinical literature.
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Adulto , Femenino , Humanos , Neoplasias Cardíacas/diagnóstico , Linfangioma/diagnóstico , Invasividad Neoplásica , Neoplasias Primarias Secundarias/diagnóstico , Neoplasias Pélvicas/patología , Arteria Pulmonar/patología , Vena Cava Inferior/patologíaRESUMEN
BACKGROUND: Propofol and remifentanil are used for tracheal intubation in the absence of neuromuscular blocking agents. We hypothesized that the addition of sevoflurane to propofol and remifentanil would improve intubation conditions and provide hemodynamic stability. METHODS: Seventy-six patients scheduled for elective surgery were randomly allocated to be ventilated with either 4% (group I) or 7% sevoflurane (group II) after propofol injection (2 mg/kg). All patients received remifentanil (1 microgram/kg) 30 seconds after administration of propofol. Ninety seconds after remifentanil was given, laryngoscopy and tracheal intubation were performed. Intubation conditions and hemodynamic changes were evaluated. RESULTS: The overall incidence of clinically acceptable intubation conditions was significantly higher in group II (92%) than group I (58%) (P = 0.001). Scores for vocal cord position, coughing, and limb movement were significantly better in group II (P < 0.05). Mean blood pressure remained significantly lower than the pre-induction level throughout the investigation in both groups (P < 0.001), but there was no incidence of bradycardia or hypotension requiring treatment. CONCLUSIONS: Tracheal intubation without neuromuscular blocking agents can be achieved safely and reliably by adding 7% sevoflurane to propofol (2 mg/kg) and remifentanil (1 microgram/kg).
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Humanos , Presión Sanguínea , Bradicardia , Tos , Extremidades , Hemodinámica , Hipotensión , Incidencia , Intubación , Laringoscopía , Éteres Metílicos , Bloqueo Neuromuscular , Bloqueantes Neuromusculares , Piperidinas , Propofol , Pliegues VocalesRESUMEN
BACKGROUND: Percutaneous cannulation of internal jugular vein is difficult in pediatric patients because of its small size and anatomic variation. The aim of this study is to investigate cross-sectional area and relative anatomy of right internal jugular vein with respect to the carotid artery in two approaches and thereby to find ideal cannulation site in young children. METHODS: The cross-sectional area of right internal jugular vein and the degree of the carotid artery overlap was evaluated in 47 children using ultrasound at two levels; 1) at the cricoid cartilage (high approach) and 2) at the junction of the two heads of the sternocleidomastoid muscle (low approach). RESULTS: The cross-sectional area was significantly larger by about 28.8% in the low approach than that of the high approach (P < 0.01). The internal jugular vein was partially overlapping the carotid artery in 48.9% and completely overlapping in 42.6% in the low approach and in 44.7% and 34.0% in the high approach respectively. The carotid artery overlap was significantly higher in the low approach when compared with the high approach (P < 0.02). CONCLUSIONS: In terms of cross-sectional area, the low approach with larger size is optimal for internal jugular vein cannulation. Although the degree of the carotid artery overlap was higher at the low approach, the internal jugular vein was partially or completely covering the carotid artery in most patients in both approaches. When attempting to cannulate the internal jugular vein, clinicians should be aware of the large anatomic variations.
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Niño , Humanos , Variación Anatómica , Arterias Carótidas , Cateterismo , Cartílago Cricoides , Cabeza , Venas Yugulares , MúsculosRESUMEN
BACKGROUND: Sevoflurane has a low blood-gas partition coefficient, resulting in rapid induction and recovery. We compared the effects of sevoflurane with those of enflurane anesthesia on parturients and neonates during and after elective cesarean section. METHODS: Ninety-six parturients were divided into two groups: E (enflurane, n = 47) and S (sevoflurane, n = 49). After endotracheal intubation with intravenous administration of thiopental 4 mg/kg and succinylcholine 1.5 mg/kg, anesthesia was maintained with 50% nitrous oxide in oxygen and enflurane 1 vol% or sevoflurane 1 vol%. Maternal hemodynamic parameters, blood loss, and recovery were monitored. Neonatal outcome was evaluated by Apgar scores, umblical artery blood gas analysis and acid-base status. RESULTS: Recovery times were faster with sevoflurane anesthesia (P < 0.05). All patients in two groups developed transient hypertension and tachycardia after intubation, which returned to baseline in approximately 5 minutes. Maternal blood loss did not differ significantly between the two groups, and one patient in S group developed postoperative recall. Neonatal outcome was equally good in the two groups. CONCLUSIONS: Parturients anesthetized with sevoflurane for cesarean section recovered more rapidly compared with enflurane without any differences in hemodynamic parameters and neonatal outcome.
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Femenino , Humanos , Recién Nacido , Embarazo , Administración Intravenosa , Anestesia , Arterias , Análisis de los Gases de la Sangre , Cesárea , Enflurano , Hemodinámica , Hipertensión , Intubación , Intubación Intratraqueal , Óxido Nitroso , Oxígeno , Succinilcolina , Taquicardia , TiopentalRESUMEN
We had a case of respiratory difficulty following total thyroidectomy due to bilateral vocal cord palsy. The patient was a 49-year-old female undergoing total thyroidectomy for papillary carcinoma of the thyroid. Anesthesia was performed uneventfully. Spontaneous respiration resumed after reversal of the neuromuscular blockade. However, after arriving at the postanesthesia care unit, she developed hypertension, anxiety, tachypnea, and inspiratory stridor during deep inspiration. Because the patient maintained adequate oxygen saturation, we confirmed bilateral vocal cord palsy by fiberoptic laryngoscopy. During the operation, the surgeon experienced difficulty dissecting the bilateral recurrent laryngeal nerves from the surrounded tumor. So we consider that direct nerve injury was responsible for the bilateral vocal cord palsy. Movement of the right vocal cord recovered a week later.
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Femenino , Humanos , Persona de Mediana Edad , Anestesia , Ansiedad , Carcinoma Papilar , Hipertensión , Laringoscopía , Bloqueo Neuromuscular , Oxígeno , Nervio Laríngeo Recurrente , Respiración , Ruidos Respiratorios , Taquipnea , Glándula Tiroides , Tiroidectomía , Parálisis de los Pliegues Vocales , Pliegues VocalesRESUMEN
We had a case of respiratory difficulty following total thyroidectomy due to bilateral vocal cord palsy. The patient was a 49-year-old female undergoing total thyroidectomy for papillary carcinoma of the thyroid. Anesthesia was performed uneventfully. Spontaneous respiration resumed after reversal of the neuromuscular blockade. However, after arriving at the postanesthesia care unit, she developed hypertension, anxiety, tachypnea, and inspiratory stridor during deep inspiration. Because the patient maintained adequate oxygen saturation, we confirmed bilateral vocal cord palsy by fiberoptic laryngoscopy. During the operation, the surgeon experienced difficulty dissecting the bilateral recurrent laryngeal nerves from the surrounded tumor. So we consider that direct nerve injury was responsible for the bilateral vocal cord palsy. Movement of the right vocal cord recovered a week later.
Asunto(s)
Femenino , Humanos , Persona de Mediana Edad , Anestesia , Ansiedad , Carcinoma Papilar , Hipertensión , Laringoscopía , Bloqueo Neuromuscular , Oxígeno , Nervio Laríngeo Recurrente , Respiración , Ruidos Respiratorios , Taquipnea , Glándula Tiroides , Tiroidectomía , Parálisis de los Pliegues Vocales , Pliegues VocalesRESUMEN
BACKGROUND: Poly (ADP-ribose) polymerase (PARP) has been described as an important candidate for mediation of neurotoxicity after brain ischemia. This study was purposed to evaluate the effects of a PARP inhibitor on hypoxic-ischemic injury in the neonatal rat brain. In this study, a highly potent inhibitor of PARP, 3, 4-Dihydro-5-[4-(1-piperidinyl) butoxy]-1 (2H)-isoquinolinone (DPQ) was investigated. METHODS: Seven-day old Sprague-Dawley rat pups were used. The right common carotid artery was ligated under halothane anesthesia. After a recovery period of 3 hours, they were exposed to 8% oxygen at 37degreesC for about 120 minutes. The animals were divided into four groups: the pre-treatment group (n = 13) and post-treatment group (n = 21) were given DPQ 10 mg/kg and the pre-control group (n = 7) and post-control group (n = 14) were given a vehicle for controls. Pre-treatment and pre-control groups were injected 30 minutes prior to the hypoxic injury while post-treatment and post-control groups were injected 30 minutes after the hypoxic period intraperitoneally. The right cerebral hemisphere of the rats were examined with localized (1)H magnetic resonance spectroscopy on day 1 and 7 after the hypoxic insult. Lipid/N-acetyl aspartate (Lip/NAA) and lipid/creatine (Lip/Cr) ratios were used as apoptotic markers. On day 14, the degree of brain injury was scored by morphological changes. RESULTS: In the DPQ treated groups, the Lip/NAA and Lip/Cr ratios were lower than those of the control groups on day 1 after the hypoxic-ischemic injury (P < 0.05). However on day 7, only the ratios of the pre-treatment group were lower than those of the control group (P < 0.05). The degree of morphological changes of the brain injury on day 14 were lower in the DPQ treated groups (P < 0.05). CONCLUSIONS: These results suggest that DPQ exerts a neuroprotective effect in cerebral hypoxic-ischemic injury probably by inhibiting apoptosis especially in the early stage after an insult. Acute inhibition of PARP can have a therapeutic value in preventing ischemic brain injury.
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Animales , Ratas , Anestesia , Apoptosis , Ácido Aspártico , Lesiones Encefálicas , Isquemia Encefálica , Encéfalo , Arteria Carótida Común , Cerebro , Halotano , Espectroscopía de Resonancia Magnética , Negociación , Fármacos Neuroprotectores , Oxígeno , Ratas Sprague-DawleyRESUMEN
BACKGROUND: Fulminant hepatic failure is characterized by rapid progressive liver failure with the onset of encephalopathy within a few weeks of the appearance of jaundice. This illness is frequently complicated by hemodynamic instability, multiple organ dysfunction and intracranial hypertension associated with cerebral edema, which is the most common cause of death in this condition. We reviewed 8 cases of liver transplantation with fulminant hepatic failure with respect to anesthetic management and neurologic monitoring. METHODS: We analyzed anesthetic management, intracranial pressure (ICP), cerebral perfusion pressure (CPP), jugular venous oxygen saturation (SjvO2) and hemodynamics retrospectively during liver transplantation in 8 patients with fulminant hepatic failure. Intracranial hypertension was defined as an ICP >or= 20 mmHg for at least 5 minutes. The goal of management is to keep the CPP above 40 - 50 mmHg and ICP below 30 - 40 mmHg. There were 3 cases of hepatorenal syndrome and continous veno-venous hemodiafiltration (CVVHD) was used in 2 cases. RESULTS: All patients showed characteristic hyperdynamic circulation with severe vasodilation and vasopressive drugs were needed to maintain CPP. The episodes of intracranial hypertension occurred in all patients during transplantation. To decrease ICP, medical therapy with mannitol, furosemide and thiopental infusion were required. Intracranial hemorrhagic complications occurred in 3 cases. SjvO2 decreased transiently below 60% in 3 cases. However, it was improved with an increase of PaCO2 by hypoventilation and maintained above 60 - 80% in all cases. CONCLUSIONS: This data suggests that there is a risk of brain injury secondary to elevated ICP and low CPP during liver transplantation. ICP, CPP and SjvO2 monitoring in patients with fulminant hepatic failure can be useful for the prompt recognition of intracranial hypertension and for guiding therapy. However, correction of the coagulopathy before placement of the ICP tranducer must be performed to prevent hemorragic complications.
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Humanos , Anestesia , Edema Encefálico , Lesiones Encefálicas , Causas de Muerte , Furosemida , Hemodiafiltración , Hemodinámica , Síndrome Hepatorrenal , Hipoventilación , Hipertensión Intracraneal , Presión Intracraneal , Ictericia , Fallo Hepático , Fallo Hepático Agudo , Trasplante de Hígado , Hígado , Manitol , Oxígeno , Perfusión , Estudios Retrospectivos , Tiopental , Trasplante , VasodilataciónRESUMEN
During general anesthesia, intubation with kink-resistant armored tubes permit the anesthesiologist to work some distance from the surgical field during operation on the head and neck or with patients whose unusual position may kink and obstruct a tube not so reinforced. But armored tubes are still subject to number of hazards, including herniation of the intra-luminal cuff or layer into the lumen of the tube. So extra care is required in their use. We report a case of intraluminal herniation of armored tube accompanied with peak inspiratory pressure during general anesthesia.
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Humanos , Anestesia General , Cabeza , Intubación , CuelloRESUMEN
Hepatopulmonary syndrome is essentially the triad of liver disease, pulmonary vascular dilations and abnormal arterial oxygenation, which can result in severe hypoxia. We managed two cases of 9 and 49-year-old males for liver transplantation with hepatopulmonary syndrome. Preoperative evaluation showed decreased diffusion capacity of carbon monooxide and severe hypoxemia, while breathing room air (PaO2 < 60 mmHg) but they responded to oxygen therapy. The pulmonary vascular resistance was low, consistent with an intrapulmonary vascular shunt but the pulmonary artery pressure was normal, reflecting a high cardiac output. Intraoperative oxygenation was satisfactory (PaO2 of 100 - 200 mmHg) in spite of a high shunt fraction (Qs/Qt 18.5 +/- 9.2%). This means that the impairment in gas exchange is not the result of a true shunt, suggesting the presence of a functional shunt, which is characterized by diffusion-perfusion impairment. The intraoperative course was uneventful in the two patients and they are in a successful postoperative course. In case 1, the hypoxemia was resolved promptly, but in case 2, it was persistent for sixteen months after transplantation. The hypoxemia itself in hepatopulmonary syndrome is not regarded as a contraindication to liver transplantation. (Korean J Anesthesiol 2001; 40: 677 ~ 683)
Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Anestesia , Hipoxia , Carbono , Gasto Cardíaco Elevado , Difusión , Síndrome Hepatopulmonar , Hepatopatías , Trasplante de Hígado , Hígado , Oxígeno , Arteria Pulmonar , Respiración , Resistencia VascularRESUMEN
BACKGROUND: The aim of the present study was to detect and quantify auto-positive end-expiratory pressure (auto-PEEP) in anesthetized patients using a Laser-Flex endotracheal tube (Mallincrodt, ID, 6.0 mm), by comparing the effects of changes in tidal volume and respiratory rate. METHODS: All patients (n = 30) undergoing elective surgery were anesthetized, paralyzed and intubated with a ID 8.0 mm endotracheal tube (n = 10, control), ID 6.0 mm endotracheal tube (n = 10, group S), or ID 6.0 mm Laser-Flex endotracheal tube (n = 10, group L), respectively. After anesthetic induction, ventilator settings using a Siemens Servo 900C were changed for a tidal volume of 8, 10 ml/kg, respiratory rates of 10, 12 or 14 breaths/min. Peak airway pressure was measured and auto-PEEP was quantified using an end-expiratory occlusion method. Data recorded on the Bicore CP-100 pulmonary monitor was transfered to a PC and analyzed by processing software (ANADAT). RESULTS: In group S and L, peak airway pressure and auto-PEEP were higher than control group and increased during an increase in tidal volume (P < 0.05). But they were increased significantly during an increase of respiratory rate, only when the tidal volume was 10 ml/kg (P < 0.05). CONCLUSIONS: There was an increase of auto-PEEP in anesthetized patients using a Laser-Flex endotracheal tube during incremental changes of tidal volume and respiratory rates.
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Humanos , Respiración de Presión Positiva Intrínseca , Frecuencia Respiratoria , Volumen de Ventilación Pulmonar , Ventiladores MecánicosRESUMEN
BACKGROUND: The effects of the inhibitor of nitric oxide synthase (NOS) in cerebral ischemia have been debated. Recently, it has been suggested that it depends on the amount of the inhibitor used. Therefore, this study was carried out to evaluate the effects of the NOS in the acute ischemia-reperfusion of the cat model using variable amounts of the inhibitor. METHODS: Nineteen cats were divided into 3 groups: group 1 (n = 6), 10 mg/kg of N-nitro-L-arginine methyl ester (L-NAME); group 2 (n = 7), 0.5 mg/kg; group 3 (n = 6), control group. Incomplete global cerebral ischemia was induced by ligation of both carotid arteries with arterial hypotension (-40 mmHg) for 30 minutes followed by 3 hours of reperfusion. The NOS inhibitor (L-NAME), was injected intraperitoneally 5 minutes before reperfusion. 31P and 1H MR spectroscopy were performed. A series of spectra was acquired in the time intervals before ligation, during ischemia, and after reperfusion. RESULTS: Phosphocreatine/inorganic phosphate (PCr/Pi) ratios for group 1 were significantly lower than for groups 2 and 3 (P < 0.05), and there was no significant difference between groups 2 and 3. Lactate/N-acetyl aspartate (Lac/NAA) and lactate/creatine (Lac/Cr) ratios at 180 minutes after reperfusion were higher for group 1 than for groups 2 and 3 (P < 0.05). There were no significant differences in pH and lactate/choline (Lac/Cho) ratios among the 3 groups. CONCLUSIONS: It is demonstrated that the effect of the NOS inhibitor is dosage dependent. A high dose (10 mg/kg) of L-NAME seems to have an adverse effect on recovery of the ischemia, but a low dose (0.5 mg/kg) seems to have no effect.