RESUMO
Capnography is a useful technique in monitoring the integrity of anaesthetic equipment such as the malfunctioning of unidirectional valves in circle system. However, the lack of a precise mechanism in existing capnographs to identify the start of inspiration and the beginning of expiration in the capnograms, makes the analysis of the carbon dioxide waveforms during inspiration difficult and thus results in inaccurate assessement of rebreathing. We report a case where, during the malfunction of the inspiratory unidirectional valve in the circle system, the capnograph failed to detect the presence of substantial rebreathing. Critical analysis of the capnogram recorded during the malfunction revealed that there was substantial rebreathing which was underestimated by the capnograph as it reports only the lowest CO2 concentration rebreathed during inspiration in such abnormal situations.(AU)
Assuntos
Humanos , Pessoa de Meia-Idade , Feminino , Anestesia com Circuito Fechado/efeitos adversos , Anestesia com Circuito Fechado/instrumentação , Dióxido de Carbono/análise , Monitorização Fisiológica/métodos , Inalação , Falha de Equipamento , Monitorização Fisiológica/instrumentação , Pressão , Respiração Artificial , Ventilação Pulmonar/fisiologia , Volume de Ventilação PulmonarRESUMO
The esophagus may be the origin of chest pain clinically indistinguishable from that of ischemic heart disease. In some patients the esophageal origin of the pain may only be recognized by pharmacological provocation during manometry. We describe nine patients with chest pain which could be explained by disorders of esophageal motility-diffuse spasm in four, high pressure lower esophageal sphincter in three, and "nutcracker esophagus" in two. Methacholine provoked the pain and manometric abnormalities in five patients who had normal baseline tracings. However, seven patients given methacholine developed ischemic changes on the electrocardiogram. In one patient these were typical of Prinzmetal's variant angina. The mannometric and electrocardiographic abnormalities were reversed by intravenous atropine. Ischemic heart disease and esophageal motor disorders may occur concomitantly and pose a dilemma in diagnosis and management. (AU)
Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Doença das Coronárias/diagnóstico , Doenças do Esôfago/diagnóstico , Junção Esofagogástrica/fisiopatologia , Dor/etiologia , Tórax , Doença das Coronárias/fisiopatologia , Doença das Coronárias/diagnóstico por imagem , Deglutição/efeitos dos fármacos , Diagnóstico Diferencial , Eletrocardiografia , Doenças do Esôfago/fisiopatologia , Manometria/métodos , Compostos de Metacolina/diagnóstico , Peristaltismo , Pressão , Espasmo/induzido quimicamente , Taquicardia/induzido quimicamente , Transdutores de PressãoRESUMO
A study of rheological determinants (plasma viscosity, whole-blood viscosity, and erythrocyte deformability) was made in 24 matched pairs of patients with homozygous sickle cell disease, with and without homozygous x-thalassaemia. Patients with coexisting x-thalassaemia showed a significant increase in erythrocyte deformability measured as filtration of washed erythrocytes through 5 um diameter pores and also as viscosity of whole blood at high shear rate (230s-1) and standard haematocrit (0.45). This rheological advantage may explain the beneficial effect of x-thalassaemia 2 on haematological parameters and clinical events in homozygous sickle cell disease (AU)
