RESUMEN
Peripheral pulse oximetry has become a core monitoring modality in most fields of medicine. Pulse oximeters are used ubiquitously in operating theatres, hospital wards, outpatient clinics and general practice surgeries. This study used a portable spectrometer (Lightman(®), The Electrode Co. Ltd., Monmouthshire, UK) to measure the emission spectra of the two light emitting diodes within the pulse oximeter sensor and to determine the accuracy of 847 pulse oximeters currently in use in 29 NHS hospitals in the UK. The standard manufacturing claim of accuracy for pulse oximeters is ± 2-3% over the range of 70-100% S(p)O(2). Eighty-nine sensors (10.5%) were found to have a functional error of their electrical circuitry that could cause inaccuracy of measurement. Of the remaining 758 sensors, 169 (22.3%) were found to have emission spectra different from the manufacturers' specification that would cause an inaccuracy in saturation estimation of > 4% in the range of 70-100% saturation. This study has demonstrated that a significant proportion of pulse oximeter sensors may be inaccurate.
Asunto(s)
Oximetría/normas , Humanos , Oximetría/métodos , Reproducibilidad de los Resultados , Reino UnidoRESUMEN
This article is a review of the peri-operative use of paracetamol. It reviews the pharmacology of paracetamol, highlighting new information about the mechanism of action, and examines its therapeutic use in the peri-operative period, focusing on efficacy, route of administration, and the use of a loading dose to improve early postoperative analgesia.
Asunto(s)
Acetaminofén/uso terapéutico , Analgésicos no Narcóticos/uso terapéutico , Dolor Postoperatorio/prevención & control , Acetaminofén/efectos adversos , Acetaminofén/farmacología , Analgésicos no Narcóticos/efectos adversos , Analgésicos no Narcóticos/farmacología , Vías de Administración de Medicamentos , Esquema de Medicación , Humanos , Cuidados Posoperatorios/métodosAsunto(s)
Colinesterasas/deficiencia , Isoquinolinas/efectos adversos , Fármacos Neuromusculares no Despolarizantes/efectos adversos , Parálisis/inducido químicamente , Complicaciones Posoperatorias/inducido químicamente , Resultado Fatal , Femenino , Humanos , Isoquinolinas/administración & dosificación , Mivacurio , Fármacos Neuromusculares no Despolarizantes/administración & dosificaciónRESUMEN
Clevidipine is a new vascular-selective, calcium channel antagonist of the dihydropyridine type with an ester side chain susceptible to esterase metabolism. In healthy volunteers, it has high clearance (0.069 litres min-1 kg-1) with a small volume of distribution at steady state (0.19 litres kg-1). The half-lives of the two initial rapid phases, accounting for approximately 95% of the area under the curve after an i.v. bolus, are 0.7 and 2.3 min, respectively. The aims of this study were to determine the pharmacokinetics and the pulmonary extraction ratio of clevidipine in patients undergoing cardiac surgery. Seventeen patients received clevidipine as an i.v. infusion before cardiopulmonary bypass (CPB), and eight of these patients were also given clevidipine during hypothermic CPB. Mixed venous and arterial blood samples were taken for pharmacokinetic analysis and calculation of pulmonary extraction ratio. A two-compartment pharmacokinetic model with zero-order input was used to describe the pharmacokinetics of clevidipine before and during CPB. Virtually identical concentrations in mixed venous and arterial blood suggest negligible pulmonary metabolism of clevidipine. The total blood clearance of clevidipine is extremely high (0.055 litres min-1 kg-1). During CPB, clearance of clevidipine was significantly reduced, to 0.03 litres min-1 kg-1 (P < 0.005), probably as a consequence of reduced body temperature.
Asunto(s)
Antihipertensivos/farmacocinética , Bloqueadores de los Canales de Calcio/farmacocinética , Puente Cardiopulmonar , Pulmón/metabolismo , Piridinas/farmacocinética , Adulto , Anciano , Antropometría , Antihipertensivos/sangre , Bloqueadores de los Canales de Calcio/sangre , Femenino , Humanos , Hipotermia Inducida , Cuidados Intraoperatorios , Masculino , Persona de Mediana Edad , Piridinas/sangreRESUMEN
A telephone survey of 20 English intensive care units (ICUs) confirmed that visual estimation of patient weight is often performed. Four experienced intensive care staff (three doctors and one nurse) estimated the weight and measured the height of 30 volunteers and the estimates were compared with accurate reference measurements. The estimates were shown to be significantly inaccurate for individual observers. We consider the degree of inaccuracy to be of clinical importance. However, pooling the individual estimates of weight as mean values improved accuracy. Recommendations are made concerning the performance of height and weight determination.
Asunto(s)
Estatura , Peso Corporal , Cuidados Críticos , Adulto , Humanos , Cuerpo Médico de Hospitales , Persona de Mediana Edad , Personal de Enfermería en Hospital , Variaciones Dependientes del Observador , Estándares de Referencia , Análisis de RegresiónRESUMEN
Survival following emergency surgery for ruptured abdominal aortic aneurysm remains poor and is in stark contrast to that for elective repair. We have carried out a 5-year retrospective observational study to determine the long-term (5-year) survival of patients following emergency surgery for ruptured abdominal aortic aneurysm at a district general hospital in East Anglia. A total of 99 patients presented to the operating theatre for emergency repair of ruptured abdominal aortic aneurysm in this 5-year study period. In-hospital mortality was 70% and was unchanged over the 5 years. Overall long-term survival in those patients discharged from hospital was good. The ICU cost per long-term survivor was calculated to be pound sterling 36750.
Asunto(s)
Aneurisma Roto/cirugía , Aneurisma de la Aorta Abdominal/cirugía , Anciano , Anciano de 80 o más Años , Aneurisma Roto/economía , Aneurisma Roto/mortalidad , Aneurisma de la Aorta Abdominal/economía , Aneurisma de la Aorta Abdominal/mortalidad , Urgencias Médicas , Femenino , Costos de Hospital , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos/economía , Masculino , Pronóstico , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
A number of methods exist by which the pH of local anaesthetic solutions may be increased. Most commonly, these require the addition of differing amounts of sodium bicarbonate solution according to the local anaesthetic drugs. Sodium bicarbonate (1%) was titrated against pH in six commonly used local anaesthetic solutions. Titration curves of pH and volume of sodium bicarbonate solution added are shown for this group of local anaesthetics. This study demonstrates that 1 mL of 1% sodium bicarbonate solution may be used to alkalinize this range of local anaesthetics without the risk of precipitation. We also conclude that Ropivacaine (at concentration 0.75% and 1.0%), is unsuitable for alkalinization since it precipitates at a pH of 6.0.
Asunto(s)
Álcalis/química , Amidas/química , Anestésicos Locales/química , Bupivacaína/química , Lidocaína/química , Bicarbonato de Sodio/química , Precipitación Química , Epinefrina/química , Humanos , Concentración de Iones de Hidrógeno , Ropivacaína , Seguridad , Temperatura , VolumetríaRESUMEN
We have studied the haemodynamic changes in response to tracheal intubation in 60 ASA I women undergoing elective gynaecological surgery; 30 women smoked more than 10 cigarettes a day, while the other 30 were non-smokers. Immediately after intubation, heart rate of smokers (mean 102.0 (SD 17) beat min-1) was significantly greater (P < 0.01) than that of non-smokers (mean 91.0 (12.3) beat min-1). This may be clinically important in smokers who are at risk of ischaemic heart disease and also relevant for future studies investigating haemodynamic responses to intubation.