Symptomatic life-threating hyponatremia complicating severe COPD exacerbation, pulmonary edema and pulmonary hypertension-a critical role for conivaptan

Hyponatremia, the most common electrolyte abnormality in hospitalized patients, is associated with increased morbidity and mortality. Phase 3 clinical trials and subsequent studies including the Study of Ascending Levels of Tolvaptan in Hyponatremia 1 and 2 (SALT 1 and 2) clearly demonstrated the efficacy of vasopressin antagonists in increasing plasma sodium levels. The "vaptans", oral tolvaptan and intravenous conivaptan, are vasopressin antagonists but as recently as 2015, there remained conflicting recommendations for their use by different expert committees in patients with hyponatremia. This circumstance was blamed on limited patient experiences and limited research data. We recently encountered worsening life-threatening symptomatic hyponatremia, unresponsive to hypertonic 3% saline infusion, and impending respiratory failure in a 62-year old obese Caucasian male patient who was further complicated by advanced chronic obstructive pulmonary disease (COPD), pulmonary hypertension and acutely decompensating diastolic heart failure, albeit with stable CKD II creatinine levels. Intravenous loop diuretics may have helped with heart failure but potentially would have aggravated the already critically low sodium levels. He demonstrated a brisk response to intravenous conivaptan administration. Intravenous conivaptan is sine qua non the absolute ideal therapeutic agent for acutely decompensating congestive heart failure with concurrent life-threatening hyponatremia.