RESUMEN
Near-infrared spectrophotometry assesses cerebral oxygen saturation (ScO2) based on the absorption spectra of oxygenated and deoxygenated hemoglobin, and the translucency of biological tissue, in the near-infrared band. There is increasing evidence that optimising cerebral oxygenation, guided by ScO2, is associated with improved outcomes in a variety of high risk surgical settings. However, in patients with liver disease, bilirubin can potentially render cerebral oximetry inaccurate. As a result, measurement of cerebral oxygen saturation is rarely undertaken in patients undergoing hepatobiliary surgery. We prospectively measured baseline and intraoperative cerebral oxygen saturation in patients undergoing major pancreatic surgery. Indices including bilirubin, sodium, platelets and maximum amplitude on thromboelastography were associated with low baseline ScO2. However, those patients with low ScO2 (≤51%) maintained a similar trend in cerebral oximetry values both at induction and intraoperatively to those with a normal ScO2. We conclude that the pattern of cerebral oximetry is similar in patients undergoing major pancreatic surgery regardless of their underlying liver dysfunction. Therefore, cerebral oximetry may have a role in monitoring neurological function in this high risk group of patients.
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Encéfalo/metabolismo , Monitoreo Intraoperatorio/métodos , Oximetría/métodos , Oxígeno/sangre , Pancreatectomía/métodos , Espectroscopía Infrarroja Corta/métodos , Anciano , Femenino , Humanos , Iluminación/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
INTRODUCTION: Exertional heatstroke with liver involvement is a rare and potentially fatal condition. In this setting, fulminant hepatic failure (FHF) occurs as a result of severe hypoxic hepatitis. CASE REPORT: We report the case of a young male athlete who developed exertional heatstroke associated with rhabdomyolysis and hypoxic hepatitis while running the final stages of an ultra-marathon (62 km). The patient rapidly developed multiorgan failure, including fulminant hepatic failure, requiring intensive care admission for mechanical ventilation, hemodialysis, and inotropic support. He failed to improve with supportive measures and underwent an emergency hepatectomy followed by orthotopic liver transplant, after which he recovered completely. CONCLUSIONS: We discuss the rationale for liver transplantation in this setting, possible alternative treatments, and the pathophysiology of fulminant liver failure in this rare case.
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Golpe de Calor/complicaciones , Fallo Hepático Agudo/cirugía , Trasplante de Hígado , Adulto , Humanos , Fallo Hepático Agudo/fisiopatología , Masculino , Insuficiencia Multiorgánica/etiología , Rabdomiólisis/etiologíaRESUMEN
BACKGROUND: An increasing number of patients with alcoholic liver disease (ALD) are being referred for critical care support, but limited information is available on their short- and medium-term outcomes. This study aimed to determine mortality rates, identify optimal predictors of prognosis, and determine the appropriate time to apply these predictors in patients with ALD admitted to intensive care unit (ICU). METHODS: In this retrospective study, patients admitted to ICU between 2009 and 2012 with a primary diagnosis of ALD were included. Survival was calculated using the Kaplan-Meier method, risk factors for death determined by logistic regression analysis, and discriminative capacity of models using receiver operating characteristic curves. RESULTS: Of 170 patients admitted with liver disease, 62 met the inclusion criteria. Survival rates in the ICU, in hospital, and at 6 months were 40.3% (95% confidence interval [CI], 30.7%-49.9%), 35.5% (95% CI, 25.35%-45.65%), and 29% (95% CI, 19.4%-38.6%), respectively. Multiple linear regression analysis of day 1 variables produced an equation with Sequential Organ Failure Assessment score and lactate as significant predictors of mortality; this model had an area under the receiver operating characteristic curve of 0.93. A score greater than 12 in this model correlated with a mortality of more than 80% at all time points and was more accurate than any other score examined. CONCLUSION: Patients admitted to ICU with ALD have a very high inhospital mortality. A combination of the established Sequential Organ Failure Assessment score and lactate provided the most accurate predictor of outcome on day of admission and at all subsequent time points.
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Hepatopatías Alcohólicas/mortalidad , Adulto , Anciano , Intervalos de Confianza , Cuidados Críticos , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Pronóstico , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tasa de SupervivenciaAsunto(s)
Síndrome de Dificultad Respiratoria/patología , Síndrome de Dificultad Respiratoria/terapia , Terminología como Asunto , Humanos , Hipoxia/etiología , Hipoxia/fisiopatología , Hipoxia/terapia , Alveolos Pulmonares/patología , Curva ROC , Estándares de Referencia , Síndrome de Dificultad Respiratoria/diagnósticoRESUMEN
Acute respiratory distress syndrome is one of the leading causes of death in critically ill patients. Recent advances in supportive care have led to a moderate improvement in mortality. In particular, a much lower mortality rate than expected was evident in the severest category of patients (requiring extracorporeal membrane oxygenation) in Australia during the recent H1N1 pandemic. Though improvements in supportive care may have provided some benefit, there remains an absence of effective biological agents that are necessary to achieve further incremental reduction in mortality. This article will review the evidence available for current treatment strategies and discuss future research directions that may eventually improve outcomes in this important global disease.
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Síndrome de Dificultad Respiratoria/terapia , Oxigenación por Membrana Extracorpórea , Ventilación de Alta Frecuencia , Humanos , Postura , Posición Prona , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/fisiopatología , Vasodilatadores/uso terapéuticoRESUMEN
Practising physicians individualise treatments, hoping to achieve optimal outcomes by tackling relevant patient variables. The randomised controlled trial (RCT) is universally accepted as the best means of comparison. Yet doctors sometimes wonder if particular patients might benefit more from treatments that fared worse in the RCT comparisons. Such clinicians may even feel ostracised by their peers for stepping outside treatments based on RCTs and guidelines. Are RCTs the only acceptable evaluations of how patient care can be assessed and delivered? In this controversy we explore the interpretation of RCT data for practising clinicians facing individualised patient choices. First, critical care anaesthetists John Boylan and Brian Kavanagh emphasise the dangers of bias and show how Bayesian approaches utilise prior probabilities to improve posterior (combined) probability estimates. Secondly, Jane Armitage, of the Clinical Trial Service Unit in Oxford, argues why RCTs remain essential and explores how the quality of randomisation can be improved through systematic reviews and by avoiding selective reporting.
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Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Teorema de Bayes , Sesgo , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricosRESUMEN
OBJECTIVES: This study examined the effects of interleukin-1 beta on isometric tension development and relaxation in isolated rat aortic rings in response to the alpha-1 adrenergic agonist phenylephrine, the endothelium-dependent vasodilator acetylcholine, and the endothelium-independent vasodilator sodium nitroprusside. DESIGN: Randomized, controlled, paired design. SETTING: Animal laboratory within a university department of physiology. SUBJECTS Paired aortic thoracic aortic rings from specific pathogen-free Sprague-Dawley rats. INTERVENTIONS: Series I examined the potential for interleukin-1 beta to cause early arterial endothelial dysfunction. Paired aortic rings were incubated for 2 hrs with interleukin-1 beta or vehicle. Series II examined the potential for inhibition of DNA transcription to attenuate interleukin-1 beta-mediated endothelial dysfunction. Paired rings received either dactinomycin or vehicle before interleukin-1 beta incubation. Series III quantified the degree to which inhibition of DNA transcription inhibited early interleukin-1 beta-mediated endothelial dysfunction. Paired rings received either dactinomycin pretreatment followed by interleukin-1 beta incubation, or pretreatment and incubation with inert vehicles. Series IV assessed the effects of interleukin-1 beta on responsiveness to an exogenous nitric oxide donor, sodium nitroprusside, in the presence of the nitric oxide synthesis inhibitor N omega-nitro-L-arginine methyl ester. MEASUREMENTS AND MAIN RESULTS: Incubation with interleukin-1 beta for 2 hrs had no effect on contractile response but attenuated endothelium-dependent relaxation significantly relative to control. Dactinomycin pretreatment inhibited early interleukin-1 beta-mediated endothelial dysfunction. The combination of interleukin-1 beta and dactinomycin produced effects on endothelium-dependent relaxation that were not different from that seen in rings not exposed to interleukin-1 beta. Interleukin-1 beta attenuated responsiveness to sodium nitroprusside relative to control. CONCLUSIONS: Interleukin-1 beta causes an early impairment of endothelium-dependent vasorelaxation with an onset that precedes its effects on systemic contractility. This impairment occurs via a mechanism that is wholly or predominantly dependent on DNA transcription. The altered vasorelaxation induced by interleukin-1 beta is at least partly mediated by a reduction in nitric oxide responsiveness.
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Aorta Torácica/fisiopatología , ADN , Modelos Animales de Enfermedad , Endotelio Vascular/fisiopatología , Interleucina-1/inmunología , Sepsis/inmunología , Sepsis/fisiopatología , Transcripción Genética , Vasodilatación/inmunología , Acetilcolina/inmunología , Acetilcolina/farmacología , Agonistas alfa-Adrenérgicos/inmunología , Agonistas alfa-Adrenérgicos/farmacología , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/inmunología , Dactinomicina/inmunología , Dactinomicina/farmacología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/inmunología , Técnicas In Vitro , Interleucina-1/farmacología , Masculino , Nitroprusiato/farmacología , Fenilefrina/inmunología , Fenilefrina/farmacología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Transcripción Genética/efectos de los fármacos , Transcripción Genética/fisiología , Vasoconstrictores/inmunología , Vasoconstrictores/farmacología , Vasodilatación/efectos de los fármacos , Vasodilatadores/inmunología , Vasodilatadores/farmacologíaRESUMEN
BACKGROUND: Postoperative residual curarization (PORC) after surgery is common and its detection has a high error rate. Artificial neural networks are being used increasingly to examine complex data. We hypothesized that a neural network would enhance prediction of PORC. METHODS: In 40 previously reported patients, neuromuscular function, neuromuscular block/antagonist usage and time intervals were recorded throughout anaesthesia until tracheal extubation by an observer uninvolved in patient care. PORC was defined as significant 'fade' (train of four <0.7) at extubation. Neuromuscular function was classified as PORC (value=1) or no PORC (value=0). A back-propagation neural network was trained to assign similar values (0, 1) for prediction of PORC, by examining the impact of (i) the degree of spontaneous recovery at reversal, and (ii) the time since pharmacological reversal, using the jackknife method. Successful prediction was defined as attainment of a predicted value within 0.2 of the target value. RESULTS: Twenty-six patients (65%) had PORC at tracheal extubation. Clinical detection of PORC had a sensitivity of 0 and specificity of 1, with an indeterminate positive predictive value and a negative predictive value of 0.35. Using the artificial neural network, one patient with residual block and one with adequate neuromuscular function were incorrectly classified during the test phase, with no indeterminate predictions, giving an artificial neural network sensitivity of 0.96 (chi(2)=44, P<0.001) and specificity of 0.92 (P=1), with a positive predictive value of 0.96 and a negative predictive value of 0.93 (chi(2)=12, P<0.001). CONCLUSIONS: Neural network-based prediction, using readily available clinical measurements, is significantly better than human judgement in predicting recovery of neuromuscular function.
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Redes Neurales de la Computación , Bloqueo Neuromuscular/efectos adversos , Enfermedades de la Unión Neuromuscular/diagnóstico , Adulto , Femenino , Humanos , Intubación Intratraqueal/efectos adversos , Masculino , Unión Neuromuscular/efectos de los fármacos , Enfermedades de la Unión Neuromuscular/inducido químicamente , Valor Predictivo de las Pruebas , Estudios RetrospectivosRESUMEN
BACKGROUND: Residual paralysis following the use of neuromuscular blocking drugs remains a clinical problem. As part of departmental quality assurance, we examined the degree of postoperative residual curarization (PORC) following atracurium. METHODS: Forty patients undergoing general anaesthesia involving atracurium were studied. Quantitative neuromuscular monitoring (mechanomyography, Myograph 2000, Biometer, Denmark) was performed by assessing the response to supramaximal train-of-four (TOF) stimulation of the ulnar nerve. Anaesthesia was provided by non-participating clinicians who were blinded to the study data. A TOF ratio
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Atracurio/efectos adversos , Fármacos Neuromusculares no Despolarizantes/efectos adversos , Parálisis/inducido químicamente , Complicaciones Posoperatorias/inducido químicamente , Adulto , Intervalos de Confianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Bloqueo Nervioso , Oportunidad Relativa , Parálisis/fisiopatología , Nervios Periféricos/fisiopatología , Estimulación Física , Complicaciones Posoperatorias/fisiopatología , Factores de TiempoRESUMEN
BACKGROUND: Post-operative nausea and vomiting (PONV) is common, especially following gynaecological surgery. Patient-controlled analgesia (PCA) is frequently complicated by nausea. We assessed PONV, pain and sedation in patients receiving cyclizine or droperidol during PCA following abdominal hysterectomy in a double-blind trial. METHODS: Thirty women were randomised to receive either cyclizine 0.7 mg/kg or droperidol 0.04 mg/kg during surgery followed by PCA containing morphine sulphate with cyclizine 2 mg or droperidol 0.05 mg per demand. Blinded observers scored levels of nausea, sedation, anxiety and pain. RESULTS: Pain scores, PCA usage and supplemental antiemetic requirements were comparable. Nausea and sedation scores were similar in both groups. Two patients in each group developed refractory PONV. Pre-operative anxiety scores were similar and decreased comparably over time. Patients developing refractory emetic sequelae had a higher incidence of previous PONV. Previous PONV also predicted lower PCA medication intake despite similar demand rates, suggesting increased usage during lock-out periods. CONCLUSION: Prophylactic cyclizine and droperidol have similar efficacy during PCA. Neither is associated with perioperative anxiety. A minority of patients have refractory PONV during PCA. Previous PONV may predict less efficient PCA usage.
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Analgesia Controlada por el Paciente , Antieméticos , Ciclizina , Droperidol , Histerectomía , Náusea y Vómito Posoperatorios/epidemiología , Analgésicos Opioides/administración & dosificación , Antieméticos/efectos adversos , Ansiedad/prevención & control , Ciclizina/efectos adversos , Método Doble Ciego , Droperidol/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Morfina/administración & dosificación , Dolor Postoperatorio/prevención & control , Náusea y Vómito Posoperatorios/prevención & control , PremedicaciónRESUMEN
BACKGROUND: Patient knowledge of perioperative care, particularly the role of the anaesthetist, appears limited. AIM: This study investigated patients' knowledge of common medical terms, of their surgical care, of the role of the anaesthetist, and their preoperative fears and concerns about postoperative pain. We examined the changes in their knowledge base as a result of the pre-anaesthetic visit and their inpatient stay. METHODS: Three hundred patients were surveyed on three separate occasions, before a routine pre-anaesthetic visit, two to three hours after this visit and on the day of discharge from hospital. RESULTS: Patients' knowledge of medical terms, their surgical procedure, and the role of the anaesthetist in their perioperative care were limited. There was little change following either the pre-anaesthetic visit or postoperative convalescence. Misconceptions, about such issues as postoperative pain, appeared to increase by the end of their hospital stay. Male patients, older patients and patients in lower socio-economic groups had poorer knowledge. A significant proportion of patients remained unaware that the anaesthetist was medically qualified. CONCLUSIONS: Patients' knowledge of perioperative care is limited, with very little change during hospital stay. Novel educational approaches may be required to increase basic medical knowledge.
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Anestesia , Conocimientos, Actitudes y Práctica en Salud , Atención Perioperativa , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Educación del Paciente como AsuntoRESUMEN
Differential phosphorylation of the retinoblastoma protein plays a pivotal role in cell cycle regulation. The retinoblastoma protein is specifically phosphorylated during the cell cycle by cyclin-dependent kinase complexes which intersect with many cellular signaling networks. Since the loss of the retinoblastoma signaling pathways occurs in a wide variety of human tumors, understanding the significance of site-specific phosphorylation can clarify the role of selected cyclin-dependent kinase complexes during cell cycle progression. Here we describe the phosphospecificity and cellular characterization of a panel of polyclonal antibodies that recognize unique phosphorylation sites within the retinoblastoma protein. These reagents were used to validate authentic cellular retinoblastoma phosphorylation sites at amino acids 780, 795, and 807/811 correlating with the G1-S transition.
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Proteína de Retinoblastoma/metabolismo , Animales , Sitios de Unión , Ciclo Celular , Línea Celular , Humanos , Fosforilación , ConejosRESUMEN
Ambulatory surgery has proliferated as a result of increasing inpatient costs. Its high level of safety has resulted in its extension to less healthy, often elderly patients. Patient compliance with instructions is essential to avoid morbidity. We aimed to identify subgroups potentially at risk due to non-compliance. A confidential questionnaire was administered to 220 consecutive daycase patients. Data included: patient demographics, duration of fasting, taking of medications that morning, importance of fasting and medication instructions, mode of post-discharge transport, and whether they had someone to stay with them that night. Seven (3.5 per cent) patients admitted to non-compliance with fasting instructions, with 8 per cent considering these instructions non-essential. Thirteen of 59 patients on medications took them against instructions, with 9 patients considering the instructions non-essential. Eight patients admitted intending to drive home; 7 per cent admitted to having no one to stay with them on the night of surgery. A significantly minority of patients (particularly male) admit to non-compliance with ambulatory surgery instructions; these figures may be underestimates. Absence of anaesthetic/medical input and lack of reinforcement probably contribute to non-compliance. Some medication-related non-compliance may be appropriate (e.g. antianginals, antihypertensives) and may reflect conflicting instructions given to the patient. The stopping of all medications prior to ambulatory surgery needs revision. Older patients living alone may not be suitable candidates for ambulatory anaesthesia.
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Procedimientos Quirúrgicos Ambulatorios , Cooperación del Paciente , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Socioeconómicos , Encuestas y CuestionariosRESUMEN
BACKGROUND: The efficacy and effects of epidural analgesia compared with patient-controlled analgesia (PCA) have not been reported in patients undergoing major vascular surgery. We compared the effects of epidural bupivacaine-morphine with those of intravenous PCA morphine after elective infrarenal aortic surgery. METHODS: Forty patients classified as American Society of Anesthesiologists physical status 2 or 3 received general anesthesia plus postoperative PCA using morphine sulfate (group PCA; n = 21) or general anesthesia plus perioperative epidural morphine-bupivacaine (group EPI; n = 19) during a period of 48 h. During operation, EPI patients received 0.05 mg/kg epidural morphine and 5 ml 0.25% bupivacaine followed by an infusion of 0.125% bupivacaine with 0.1% morphine (0.1 mg/ ml); group PCA received 0.1 mg/kg intravenous morphine sulfate. Continuous electrocardiographic monitoring (V4 and V5 leads) was performed from the night before surgery until 48 h afterward. Respiratory inductive plethysmographic data were recorded after tracheal extubation. Visual analog pain scores at rest and after movement were performed every 4 h after extubation. RESULTS: Nurse-administered intravenous morphine and time to tracheal extubation were less in group EPI, as were visual analog pain scores at rest and after movement from 20 to 48 h. Complications and the duration of intensive care unit and hospital stay were comparable. There was a similar, low incidence of postoperative apneas, slow respiratory rates, desaturation, and S-T segment depression. CONCLUSIONS: Epidural morphine-bupivacaine is associated with reduced early postoperative intravenous opioid requirements, more rapid tracheal extubation, and superior analgesia after abdominal aortic surgery, with comparable respiratory effects.