Một kết quả phản ứng phản vệ biểu hiện lâm sàng tương tự như một phản ứng phản vệ, nhưng không phải là trung gian của một kháng thể IgE nhạy cảm. Trước khi tiếp xúc với một loại thuốc sẽ không có xảy ra, nhưng cá nhân nhạy cảm thường có tiền sử dị ứng. Mỗi bác sĩ gây mê nên biết và thực hành một "phản ứng phản vệ khoan". | emedicina Common intraoperative problems Box Major causes of intraoperative hypotension Decreased venous return haemorrhage vena caval compression - obstetrics prone position drugs infection Myocardial depression mechanical intermittent positive pressure ventilation equipment and circuit malfunction pneumothorax cardiac tamponade pulmonar y embolus cardiac disease drugs Treatment Treatment is dependent on correct identification of the cause. Rapid intravenous infusion of colloid fluid or blood may be required together with measurement of the central venous pressure. The use of inotropic drugs should only be considered when you are sure that there is an adequate circulating blood volume. Epinephrine adrenaline is not an appropriate treatment for the hypotension of haemorrhage. Laryngospasm Reflex closure of the glottis from spasm of the vocal cords is due usually to laryngeal stimulation. Common causes include insertion of a Guedel airway or laryngoscope the presence of a tracheal tube and secretions in the airway. It can also arise as a response to surgical stimulation in a lightly anaesthetised patient. Thus it occurs not only on induction of anaesthesia but also intraoperatively and occasionally postoperatively. The airway obstruction can lead to hypoxia and in severe cases pulmonary oedema can result. Treatment The management of laryngospasm depends on its severity as shown in Box . 89 emedicina How to Survive in Anaesthesia Box Management of laryngospasm 1 Identify stimulus and remove if possible. 2 Give 100 O2 and get help. 3 Ensure patent airway. 4 Tighten expiratory valve to apply a positive airway pressure to break the spasm and increase O2 intake with each breath. BE CAREFUL. 5 If unable to ventilate give suxamethonium endotracheal intubation and deepen anaesthesia. Ensure intubation and ventilation is feasible. There is a belief that a patient with severe laryngospasm and cyanosis will gasp a breath just before hypoxaernia is fatal. Do not .