Respiratory

Advanced respiratory nursing means recognizing a patient who is failing to oxygenate or ventilate before the numbers become extreme, choosing and titrating oxygen and ventilatory support safely, keeping airways clear without causing harm, and escalating early. Two jobs of the lung must be kept separate. Oxygenation is the transfer of oxygen from alveolar gas into blood (reflected by PaO2 and SpO2). Ventilation is the movement of gas in and out of the lungs that clears carbon dioxide (reflected by PaCO2). A patient can fail at either job, or both, and the treatment differs. Arterial blood gas (ABG) reference values for an adult are pH 7.35 to 7.45, PaCO2 35 to 45 mmHg, PaO2 about 80 to 100 mmHg on room air, and bicarbonate (HCO3-) about 24 mmol/L (laboratory reference ranges vary; 22 to 26 mmol/L is commonly printed). The Henderson-Hasselbalch relationship, pH = 6.1 + log([HCO3-] / [0.03 x PaCO2]), shows why: with HCO3- 24 mmol/L and PaCO2 40 mmHg the ratio of bicarbonate to dissolved carbon dioxide is 24 / 1.2 = 20 to 1, and pH stays near...