Thirst perception and osmoregulation of vasopressin secretion are altered during recovery from septic shock.

Abstract

ObjectiveVasopressin (AVP) secretion during an osmotic challenge is frequently altered in the immediate post-acute phase of septic shock. We sought to determine if this response is still altered in patients recovering from septic shock.DesignProspective interventional study.SettingIntensive care unit (ICU) at Raymond Poincaré and Etampes Hospitals.PatientsNormonatremic patients at least 5 days post discontinuation of catecholamines given for a septic shock.InterventionOsmotic challenge involved infusing 500 mL of hypertonic saline solution (with cumulative amount of sodium not exceeding 24 g) over 120 minutes.Measurements and main resultsPlasma AVP levels were measured 15 minutes before the infusion and then every 30 minutes for two hours. Non-responders were defined as those with a slope of the relation between AVP and plasma sodium levels less than ConclusionMore than half of patients recovering from septic shock have an alteration of osmoregulation characterised by a dramatic decrease in vasopressin secretion and thirst perception during osmotic challenge. The mechanisms of this alteration but also of the relationship between haematosis and normal response remain to be elucidated.