الفهرس 
Anatomy and Physiology of the Respiratory SystemOnly 14 pages are availabe for public view
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Abstract
Respiratory problems are one of the most frequently problems in anesthetic practice, contribute significantly to morbidity and mortality in surgical patients.
These problems include obstructive pulmonary diseases as (bronchial asthma and COPD), restrictive pulmonary diseases (acute and chronic), primary pulmonary hypertension, pulmonary pneumonia as (active TB), and pulmonary cancer, also end stage lung transplantation.
A review of normal anatomy and physiology of respiratory system, pathophysiology of obstructive and restrictive pulmonary diseases were discussed with some details in this essay.
Preoperative assessment of the patient’s condition was discussed to help in reducing the expected complications and their management that could be achieved by careful history, examination and investigations including pulmonary function tests in details.
Preoperative preparation was important goal, intending to improve the respiratory condition as possible through eradication of infection, cessation of smoking, treatment of bronchospasm and chest physiotherapy.
An optimal narcotic and sedative premedications should allay anxiety, improve work of breathing, and possibly avert the induction of bronchospasm, while avoiding oversedation and respiratory depression.
Choice of induction technique could be intravenous (as propofol, ketamine and thiopental) or inhalational, which guided primarily by the patient’s condition and by consideration of the ease with which the trachea may be intubated.
Regional blocks or neuraxial anesthesia, if not contraindicated by anticoagulation, would be used as long as the effects of loss of sympathetic tone, preload reduction, and bradycardia were considered. For these reasons, slow titration of an epidural or continuous spinal block might be safer than the rapid onset of a single shot spinal.
Maintenance of anesthetic depth was discussed in order to keep the stability of the respiratory and cardiovascular systems, with various inhalational agents as sevoflurane, isoflurane, and halothane or by total intravenous anesthesia (TIVA).
Concerning muscle relaxation were discussed with each pulmonary problem providing the safety on respiratory and cardiovascular systems, the disadvantages of them in each situation.
The control of mechanical ventilation should be manipulated whether spontaneous or assisted controlled based on the patient’s underlying disease process. One lung ventilation was also mentioned in different situation when needed. A brief review of intraoperative monitoring was also mentioned in this article.
Reversal of neuromuscular block was done by atropine or glycopyrrolate followed by neostigmine to avoid precipitation of bronchospasm and its pro-secretory effect.
Deep extubation had been practiced, but it had its own inherent hazards. It mandates full reversal of neuromuscular block. Even if tracheal extubation was smooth, emergence through the arousal stage could initiate severe bronchospasm and laryngospasm.
Postoperative management was also discussed according each situation regarding recovery duration and satisfactory ventilation. The use of elective postoperative artificial ventilation would be required in some cases.
Postoperative pulmonary complications include pain, hypoxemia, hypoventilation, atelactasis; pneumonia and respiratory failure were discussed. Consequently understanding of the risk factors associated with postoperative pulmonary complications was essential to develop strategies for reducing these complications