Hyponatremia in spinal cord injury patients: new insight into differentiating between the dilution and depletion forms

Abstract

Study design: This is a retrospective study. Objectives: The objectives of this study were to present a new model for differentiating between the dilution and depletion forms of hyponatremia in patients in the postacute phase after spinal cord injury (SCI), and to identify possible etiological factors contributing to hyponatremia in these patients. Setting: University Hospital Motol, Prague, Czech Republic. Methods: Eighty-seven of 352 patients hospitalized in 2008-2012 in the Spinal Cord Unit were hyponatremic. Seventy-four patients had S Na+ = 130-135 mmol l − 1 and 13 patients had S Na+ below 130 mmol l − 1 . We propose a simple model of an electrolyte solution in which the Na + concentration is higher than the Cl − concentration, making it possible to compare the effects of dilution and depletion of Na + and Cl − on the Na + concentration. The depletion of Na + and Cl − leads to a significant increase in the Na + /Cl − ratio, with the Na + -Cl − value remaining unchanged. Dilution with water results in a decrease of Na + -Cl − with the Na + /Cl − ratio remaining unchanged. Results: In patients with S Na+ below 130 mmol l − 1 , hyponatremia was consistent with the depletion model in 46% and with the dilution model in 32%. In patients with S Na+ ranging between 130 and 135 mmol l − 1 , the respective rates were 34 and 12%. Conclusion: Examination of S Na+ -S Cl − and S Na+ /S Cl − in patients with SCI could be helpful in considering whether hyponatremia is consistent either with the NaCl dilution model or with the NaCl depletion model. Further studies are needed for more accurate interpretation of the results, particularly with respect to volume and acid-base disorders.

Nutritional blood parameters and nutritional risk screening in patients with spinal cord injury and deep pressure ulcer—a retrospective chart analysis

“…Therefore, we recommend regular testing und supplementation if necessary. Sodium was reduced in 24% of our population compared to the general SCI population admitted to a hospital [33] and sodium levels should be regularly tested and treated. Selenium deficiency was found in 10% and because it is supplemented without any side effects to optimize wound healing [34], no regular screening seems necessary.…”

Clinical case of combined diabetes insipidus and cerebral salt-wasting syndrome in a patient with craniocerebral and spinal injury

“…В частности увеличенное давление спинномозговой жидкости в комбинации с другими факторами при травме шейного отдела СМ может приводить к СНСАГ. В свою очередь острая травма шейного отдела СМ, осложнённая гипонатриемией, может обуславливать повышение давления спинномозговой жидкости [14,15]. При этом адекватная и своевременная коррекция электролитного дисбаланса является решающей при восстановлении пациентов со спинномозговой травмой [4].…”

A study of predictors for hyponatraemia in patients with cervical spinal cord injury

“…The following variables were evaluated retrospectively by univariate logistic regression analysis: (1) age, (2) sex, (3) BP, (4) tracheostomy, (5) serum potassium, (6) serum chloride, (7) serum bicarbonate, (8) serum albumin, (9) intravenous intake and urine volume for 24 h, (10) haematocrit, (11) haemoglobin and the neurological assessment and radiological parameters stated above. To prevent missing potential predictors, Po0.10 was considered statistically significant in the univariate logistic regression analyses.…”

“…8 Therefore, impairment of the central nervous system may lead to either water retention, salt wasting or a combination of the two. 5,11 Previous studies have reported certain risk factors for hyponatraemia in CSCI patients, including low BP, severe paralysis, other electrolyte disturbances (serum potassium, serum chloride) and excessive water intake. 4,7 However, these factors might have many confounders.…”