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KEY POINTS
Restrictive lung diseases are comprised of extrinsic disorders involving the chest wall, such as kyphoscoliosis, obesity, or muscle weakness disorders, and intrinsic disorders involving the lung parenchyma.
In extrinsic restriction, low tidal volumes and high respiratory rates likely minimize the risk of barotrauma during mechanical ventilation; however, gradual institution of anti-atelectasis measures may improve gas exchange and static compliance.
Nocturnal hypoxemia is common and may contribute to cardiovascular deterioration; routine polysomnography is recommended.
Strategies for management of patients with chronic ventilatory failure include daytime intermittent positive pressure ventilation, nocturnal noninvasive ventilation, and ventilation through tracheostomy.
Acute deterioration in respiratory status can occur from disease progression, upper and lower respiratory tract infections, congestive heart failure, failure to clear secretions, atelectasis, aspiration, and pulmonary embolism.
Intrinsic restrictive lung diseases involve parenchymal reduced lung volumes as a defining feature, whereby the underlying disease and antecedent treatment, such as immunosuppression, can impact prognosis and management.
Hypoxemia results from ventilation-perfusion mismatch that is accentuated with increased cardiac output and atelectasis associated with sleep.
Patients with interstitial lung diseases and pulmonary fibrosis admitted to the ICU with acute respiratory failure have an extremely poor prognosis.
If mechanical ventilation (MV) is deemed appropriate, the use of low tidal volumes and high respiratory rates during MV likely minimize ventilator-induced lung injury.
Decisions for pharmacotherapy and antibiosis hinge upon accurate diagnosis of underlying pathology and pretest probability for infectious processes.
Lung transplantation is a viable option in selected patients with end-stage fibrosis.
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Both extrinsic diseases, such as thoracic cage deformity and obesity, and intrinsic diseases, such as pulmonary fibrosis, result in a restrictive limitation to breathing. Although relatively rare in the context of pulmonary intensive care, these disorders present unique challenges that complicate ICU management. In this chapter, we describe the pathophysiologic derangements in cardiopulmonary function associated with these disorders and how they affect management during acute illness. A primary goal of this chapter is to offer a strategy for cardiovascular management and mechanical ventilation (MV) that minimizes the risk of ventilator-induced complications and maximizes the chance for early, successful extubation. Many of these recommendations are grounded more on general precepts than on disease/disorder-specific evidence.
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PATIENTS WITH EXTRINSIC RESTRICTION
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Thoracic Cage Deformity
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Although a number of disorders can deform and restrict the movement of the respiratory system (Table 60-1), kyphoscoliosis (KS) is the prototypical cause of severe thoracic deformity. In many instances, KS is used to illustrate findings common to all extrinsic restrictive disorders. KS is the combination of kyphosis (posterior deformity of the spine) and scoliosis (lateral deformity of the spine). It is far more common than isolated cases of kyphosis or scoliosis, placing over 200,000 people in the United States at risk of developing respiratory failure.1 Most cases are idiopathic and begin in childhood.2 Other cases result from congenital ...