RESUMO
In 1958, an 11-year-old girl with status epilepticus was given the current treatments which failed to control the convulsions. In order to stop the fits, protect the airway, prevent hypoxia and hyperpyrexia, intermittent positive pressure ventilation (IPPV) and complete muscle paralysis with d-tubocurarine was used for a total of 6 h. The girl made a complete recovery, the first patient to do so using this plan of action.
Assuntos
Relaxantes Musculares Centrais/história , Fármacos Neuromusculares não Despolarizantes/história , Estado Epiléptico/história , Tubocurarina/história , Criança , Feminino , História do Século XX , Humanos , Intubação Intratraqueal/história , Intubação Intratraqueal/métodos , Relaxantes Musculares Centrais/uso terapêutico , Fármacos Neuromusculares não Despolarizantes/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Tubocurarina/uso terapêuticoRESUMO
Percutaneous needle tracheostomy and transtracheal ventilation continues to be advocated for the management of upper airway obstruction. Recent studies recommend the use of artificial ventilation. However, as apparatus for this is not always available and because there remains some doubt regarding conditions for successful use of needle tracheostomy during spontaneous respiration, we undertook such a study in dogs. Pressure-flow characteristics of short hollow needles 18-10 SWG were first determined. The smallest of these (14 SWG Bardic Intracath) that would deliver flow sufficient (by calculation) to meet the respiratory requirement of 10-13 kg laboratory dogs was selected for further study. Respiration was possible by spontaneous or artificial methods in the presence of complete tracheal occlusion. Little or no deterioration was noted in an hour of such breathing. Artificial ventilation by machine and by hand could considerably lower PaCO2. We conclude that the technique is possible provided appropriate needles are selected and care is given to their method of use.
Assuntos
Obstrução das Vias Respiratórias/terapia , Traqueotomia/métodos , Animais , Cães , Agulhas , Respiração Artificial/métodos , Traqueotomia/instrumentaçãoRESUMO
Six intact and seven splenectomized dogs were subjected to a similar degree of hypoxaemia while under light anaesthesia and artificial ventilation. In the intact animals, heart rate, cardiac output, myocardial contractility and oxygen consumption were increased as a result of hypoxaemia; oxygen transport was not affected. In the splenectomized animals the changes in cardiac output and myocardial contractility were small, and oxygen availability was decreased.
Assuntos
Hemodinâmica/efeitos dos fármacos , Hipóxia/fisiopatologia , Esplenectomia , Anestésicos/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Cães , Frequência Cardíaca/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Respiração ArtificialRESUMO
We have compared cardiac output, gas exchange and pulmonary mechanics during spontaneous breathing and artificial ventilaton under conditions which kept PaCO2 within the normal range and maintained constant tidal volume and inspired gas flow rate. In dogs anaesthetized with pentobarbitone and ventilated with air, artificial ventilation increased VD/VT but did not reduce Q angstrom, FRC, or CL. PaO2 increased and A-aDO2 decreased during aritificial ventilation, perhaps because of a small increase in Q angstrom and a small decrease in oxygen consumption. It appears that many of the reported deleterious effects of artificial ventilation may be due to the use of other anaesthetic agents and patterns of ventilation, and to changes in PaCO2.
