To evaluate the presence of hyponatremia and natriuresis and their association with atrial natriuretic factor in neurosurgery patients.The study included 30 patients who had been submitted to intracranial tumor resection and cerebral aneurism clipping. Both plasma and urinary sodium and plasma atrial natriuretic factor were measured during the preoperative and postoperative time periods.Hyponatremia was present in 63.33% of the patients, particularly on the first postoperative day. Natriuresis was present in 93.33% of the patients, particularly on the second postoperative day. Plasma atrial natriuretic factor was increased in 92.60% of the patients in at least one of the postoperative days; however, there was no statistically significant association between the atrial natriuretic factor and plasma sodium and between the atrial natriuretic factor and urinary sodium.Hyponatremia and natriuresis were present in most patients after neurosurgery; however, the atrial natriuretic factor cannot be considered to be directly responsible for these alterations in neurosurgery patients. Other natriuretic factors are likely to be involved. INTRODUCTION Disorders of plasma sodium concentration expose cells to hypotonic or hypertonic stress.

Although all cells are affected, the clinical manifestations are primarily neurologic. Rapid changes in plasma sodium concentrations can cause severe, permanent and sometimes lethal brain injury. Those disorders are common in neurology and neurosurgery patients who already have cerebral edema from the primary injury and whose adaptive mechanisms may be impaired with the worsening of the patients' neurologic condition. Trial reset 3.3. (-) Hyponatremia is defined as a serum sodium concentration 20mEq/L) and worse neurological states. Cerebral salt wasting syndrome (CSWS) is defined as the renal loss of sodium during intracranial disease, which leads to hyponatremia.

A decrease in extracellular fluid volume is the main cause of these alterations in neurosurgery patients. (-,-) The mechanism by which intracranial disease leads to renal salt wasting is not completely understood. The regulation of sodium homeostasis involves both humoral and neural mechanisms. Humoral factors include the renin-aldosterone axis, atrial natriuretic factor, and antidiuretic hormone.

Neural factors include the direct neural modulation of tubular sodium reabsorption and the indirect neural modulation of rennin release. Natriuretic factors may play an important role in CSWS, (,,,,,,,,,) and in recent years, several reports have attempted to identify a causal relationship between natriuretic peptide and CSWS. Amongst the various natriuretic factors, atrial natriuretic factor (ANF) might be the most probable candidate to mediate CSWS. (,,-,,,,-) ANF is produced in and released from the atrial appendages, and it seems to act in different tissues, participating in the control of fluid balance with a negative sodium balance and changes in blood volume. ANF has also been identified in areas of the central nervous system involved in cardiovascular, sodium and fluid regulation. (,,,,) ANF-containing neurons have been identified in the rat hypothalamus and lamina terminalis; however, the concentration of ANF in the brain is 10000 times lower than in the heart, making it unlikely that the brain secretion of ANF is responsible for CSWS. Although atrial stretch is thought to be the principal mechanism for cardiac ANF release, there is evidence that the central nervous system modulates cardiac ANF secretion.

Independent risk factor for mortality 6,7; it can also lead to or worsen heart failure. Of atrial fibrillation: rhythm control and rate control. Data show that patients assigned to rhythm. Download full-text PDF. Role of atrial natriuretic factor in volume control. THOMAS MAACK. Role of atrial natriuretic factor in volume control. Atrial natriuretic.

Intracranial disease may lead to a disturbance of the brain's control over ANF secretion, and, under certain conditions, excessive ANF is secreted. () The purpose of the present study was to verify the presence of hyponatremia and natriuresis and their relationships with atrial natriuretic factor in neurosurgery patients. Statistical analysis Descriptive statistics of numeric variables were performed to describe the profile of the sample.