Resp Care
-
Strategies to support oxygenation can cause substantial harm through lung stretch injury, oxygen toxicity, transfusion risks and cardiac over-stimulation. Traditional goals of maintaining near normal cardiorespiratory parameters are most likely overly simplistic and are insensitive and nonspecific for tissue hypoxic effects. ⋯ We also need to learn better ways of monitoring tissue oxygenation, especially in "mission critical" tissues. Ultimately clinical trials will be needed to determine appropriate oxygenation targets to allow permissive hypoxemia.
-
The beneficial effects of ambulatory home oxygen have been demonstrated since the 1950s, when Cotes and Gibson gave oxygen to ambulatory COPD patients from small portable high pressures cylinders in the United Kingdom. Over the ensuing 7 decades, oxygen has been prescribed to millions of COPD patients in the home setting. Additionally, it is common clinical practice to prescribe supplemental oxygen when chronic hypoxemic respiratory failure not due to COPD (eg, interstitial lung disease, pulmonary hypertension, kyphoscoliosis, and cystic fibrosis) is present or in patients with hypoxemia at hospital discharge following flares of their underlying chronic respiratory disorder, without any substantial evidence. ⋯ Research conducted in the 1970s and 1980s still provides the basis for clinical decision making and insurance coverage policies regarding long-term oxygen administration. Remarkably, little current research is being conducted to extend our knowledge regarding the indications, mechanisms, and benefits of long-term oxygen therapy. This review will focus on our current knowledge of the end points for supplemental oxygen at home, such as mortality, effects on functional performance, sensation of dyspnea, cognitive function, and quality of life, and highlight areas where future research is needed.
-
The nasal cannula has been a commonly used patient interface to provide supplemental oxygen since its introduction in the 1940s. Traditionally, it has been categorized as a low-flow device and capable of delivering a 0.4 F(IO(2)) with flows up to 6 L/min to adults with normal minute ventilation. However, there is considerable performance variability among patients and design, which results in an exponential decline in delivered F(IO(2)) as breathing frequencies increase. ⋯ HFNC therapy has also been considered valuable in perinatal care in treating the respiratory distress syndrome or supporting patients after extubation similar to nasal CPAP. At present, research-based evidence for the role of HFNC for its perinatal applications remains unclear. This review will identify proposed mechanisms for therapeutic effectiveness, current delivery equipment, guidelines for rational patient application, and direction for further research.
-
The physiologic changes that occur in ventilation during sleep contribute to nocturnal oxygen desaturation in those with lung disease. Nocturnal supplemental oxygen is often used as therapy, although convincing data exist only for those who are hypoxemic both during sleep and wake. ⋯ Because of its prevalence, obstructive sleep apnea may commonly overlap with lung disease in many patients and have important consequences. Patients with overlap syndromes may be good candidates for noninvasive ventilation during sleep.