Desmopressin (Acetate)

Desmopressin acetate, a synthetic analogue of the natural hormone vasopressin, is a medication with a wide range of applications in medical practice. Its primary function is to mimic the antidiuretic effects of vasopressin, which is crucial in the body's water retention and urine concentration mechanisms. Desmopressin has been extensively studied for its therapeutic benefits in conditions such as diabetes insipidus, nocturnal enuresis, and as a hemostatic agent in various bleeding disorders due to its ability to increase the levels of von Willebrand factor (vWF) in plasma8.

Desmopressin works by binding to V2 receptors in the renal collecting ducts, leading to the insertion of aquaporin-2 channels into the cell membrane and subsequent reabsorption of water. This results in a decrease in urine volume and an increase in urine osmolality. Additionally, desmopressin has been shown to release vWF from endothelial cells, which plays a critical role in platelet adhesion and blood clot formation. This action is particularly beneficial in patients with hemostatic imbalances, such as those with von Willebrand disease or platelet function defects8.

Applications in Cardiac Surgery

In the context of cardiac surgery, desmopressin has been evaluated for its ability to reduce perioperative blood loss. Studies have shown that patients receiving desmopressin after cardiopulmonary bypass have less blood loss compared to those who receive a placebo. The beneficial effect on hemostasis may be related to an increase in overall vWF concentration rather than a change in the distribution of high-molecular-weight multimers of vWF12. Furthermore, desmopressin has been found to be effective in reducing postoperative hemorrhage in patients who have been pretreated with aspirin before coronary artery bypass grafting3. A controlled clinical trial with thromboelastographic risk stratification identified a subgroup of patients with abnormal platelet function who may benefit from desmopressin therapy, as it reduced blood loss and the need for blood product transfusions4.

Applications in Menorrhagia

Desmopressin has also been studied for its effectiveness in treating menorrhagia, particularly related to the use of copper intrauterine devices (IUDs). A pilot study demonstrated that desmopressin significantly reduced menstrual blood loss without affecting uterine blood flow, suggesting its mechanism of action lies in enhancing local hemostasis5.

Despite its vasodilatory properties, desmopressin does not appear to reduce blood loss or transfusion requirements in uncomplicated cardiac surgical procedures6. However, its role in treating severe primary nocturnal enuresis in children has been corroborated, with significant reductions in wet nights and no serious adverse effects reported7. Desmopressin's use extends to the treatment of cranial diabetes insipidus and for renal function tests due to its selective antidiuretic properties8.