Pulmonary oxygen saturation

Monitor for changes in pulmonary symptoms such as cough, sputum production, respiratory rate, and oxygen saturation. Symptoms of an acute exacerbation should improve with antibiotics and aggressive airway clearance therapy. Pulmonary function tests should be markedly increased after 1 week and trend back to pre-exacerbation levels after 2 weeks of therapy, ft improvement lags, 3 weeks of therapy may be needed. 

Evlauation Close monitoring of pulmonary status, blood gases (if indicated), oxygen saturation, chest x-ray, blood and sputum cultures, CBC, bronchoscopy with lavage (if needed)... 

A pulmonary artery (Swan-Ganz) catheter can be used to determine central venous pressure (CVP) pulmouary artery pressure CO aud pulmonary artery occlusive pressure (PAOP), an approximate measure of the left ventricular eud-diastolic volume aud a major determinaut of left veutricular preload. CO (2.5 to 3 L/min) and mixed venous oxygeu saturatiou (70% to 75%) may be very low in a patient with extensive myocardial damage. Respiratory alkalosis is associated with low partial pressure of O2 (25 to 35 mm Hg) and alkaline pH, but uormal bicarbouate. The first two values are measured by arterial blood gas, which also yields partial pressure of carbon dioxide and arterial oxygen saturation. Circulating arterial oxygen saturation can also be measured by an oximeter, which is a noninvasive method that is fairly accurate and useful at the patient s bedside. 

Felodipine is a dihydropyridine derivative with diuretic properties (1). Its diuretic properties are not unique but are shared by other dihydropyridines. Its vasodilator-related adverse effects include flushing, headache, and tachycardia (2,3). Reduced arterial oxygen saturation has been seen in patients given intravenous felodipine for pulmonary hypertension (4,5). Along with amlodipine, but unlike other calcium channel blockers, felodipine may be safer in severe chronic heart failure accompanied by angina or hypertension. 

A 72-year-old woman, who underwent emergency resection of a giant left atrial myxoma, had pulmonary hypertension (pulmonary artery pressure 40 mmHg) and a low cardiac output (2.21/minute). Inhaled nitric oxide, 40 ppm, before cardiopulmonary bjrpass resulted in pulmonary vasodilatation and a fall in pulmonary artery pressure from 39 to 31 mmHg. This was accompanied by a fall in cardiac output from 2.4 to 1.5 1/minute and a fall in mixed venous oxygen saturation. After bypass, inhaled nitric oxide improved pulmonary and systemic hemodynamics and resulted in a rise in cardiac output from 3.0 to 3.5 l/minute. 

The safety of perflenapent has been evaluated in multicenter phase II studies in 146 patients with congestive heart failure (NYHA class III or IV, mean age 68 years), of whom 99 received perflenapent and 47 received isotonic saline, and in 134 patients with severe chronic obstructive pulmonary disease (FEVi no more than 60% of predicted, mean age 65 years), of whom 91 received perflenapent and 43 received isotonic saline (13). Blood pressure, heart rate, respiratory rate, oxygen saturation, the electrocardiogram, FEVi, complete serum biochemistry, hematology, and mental state were assessed. Adverse events were mild and required no treatment. There was no significant difference in the incidence of adverse reactions between those given perflenapent (15%) and those given placebo (11%). The most frequent adverse events with perflenapent were vasodilatation (n = 8), taste disturbance (n = 6), nausea (n = 5), and headache (n = 3). 

Whether the shift in the 02-dissociation curve that accompanies changes in the concentration of 2,3-DPG is beneficial depends largely on the oxygen saturation of arterial blood. The 2,3-DPG concentration can vary widely among patients with the same disease. For example, in severe pulmonary disease, the increase in 2,3-DPG concentration ranges from 0% to 100% in leukemia with depressed production of erythrocytes, elevations of 20-150% occur in iron deficiency, increases range from 40% to 75%. 

Five of the 11 patients did not respond to inhaled nitric oxide therapy, with either a decrease in proximal pulmonary artery pressure or an increase in systemic oxygen saturation. Each of these neonates had a predisposition toward elevation of pulmonary vascular resistance postoperatively. Two of these five patients had severe pulmonary venous hypertension requiring... 

The most common sensor is the activity sensor, which uses any of a variety of technologies (e.g., piezoelectric crystals and accelerometers) to detect body movement. Systems using a transthoracic-impedance sensor to estimate pulmonary minute ventilation or cardiac contractility are also commercially available. Numerous other sensors (e.g., stroke volume, blood temperature or pH, oxygen saturation, and right ventricular pressure) have been researched or market-released at various times. Some systems are dual-sensor, combining the best features of each sensor in a single pacing system. 

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