Current Diagnostic Approaches to Patients with Hypernatremia at University Health Network Hospitals
Abstract
Background: Hypernatremia is a common electrolyte disorder where serum Na + Concentration is >145 mM, and is frequently identified as an issue in patients admitted under general internal medicine 1,2 . The etiology can generally be classified as loss of free water or decreased intake, iatrogenic ingestion/infusion of hypertonic solution, or pseudohypernatremia 3 . It is a common practice to assume decreased intake of free water or extrarenal free water loss as the etiology, and to treat the hypernatremia with administration of hypotonic crystalloid solution without investigation of serum or urine osmolality, electrolytes, urea, or creatinine to delineate etiology 3,4 . In particular, the two often neglected diagnoses are diabetes insipidus and osmotic-induced diuresis. Etiology of hypernatremia is occasionally elusive and refractory to administration of crystalloid solution. However, laboratory investigations ordered by clinicians to properly determine underlying etiology of hypernatremia in these cases are not routine and may vary significantly. Objectives: We hypothesized that appropriate ordering of serum and urine studies by clinicians to determine the etiology of hypernatremia is related to the severity of hypernatremia. In addition, we aim to determine the etiology of hypernatremia that trigger clinician ordering of serum/urine studies. Methods: Patients admitted under general internal medicine at hospitals affiliated with the University Health Network (Toronto Western Hospital and Toronto General Hospital) between the dates of 2015 and 2019 with a serum sodium concentration of 150 mmol/L or greater were selected and assessed for completion of serum electrolytes, serum osmolality, urine electrolytes (Na, K, Cl), urine osmolality, urine creatinine, and urine urea. Discharge summaries were analysed to determine etiology and treatment of hypernatremia as well as treatments initiated. The research proposal was approved by Coordinated Approval Process for Clinical Research (CAPCR) at the University Health Network. Results: Based on our preliminary results, we were able to identify 606 cases of admitted general internal medicine patients with hypernatremia meeting our criteria. In our preliminary analysis of 47 cases, we were able to identify 18 cases (38.3%) with serum osmolality, 19 cases (40.4%) with urine osmolality, 23 cases (48.9%) with urine electrolytes, 1 case (2.1%) with urine urea, and 1 case (2.1%) with urine creatinine. There were 11 cases (23.4%) with all of serum osmolality, urine osmolality, and urine electrolytes. In general, the severity of hypernatremia correlated poorly with the number additional investigations ordered beyond serum electrolytes (ie. serum osmolality and urine studies; r 2 = 0.0204). Conclusion: In this study of patients with hypernatremia we found that a significant portion of admitted patients were not evaluated for urine studies, especially urea or creatinine. Unexpectedly, the severity of hypernatremia correlated poorly with the number of studies ordered to determine etiology, suggesting that the severity of hypernatremia may play a minor role in clinician ordering habits in hypernatremia. The current study signifies the importance of proper ordering and understanding of pathophysiology of hypernatremia and could contribute to filling the knowledge gap in appropriate ordering in hypernatremia, which may reduce the morbidity and mortality rate of hypernatremic patients.
Details
- Journal: Canadian Journal of Anesthesia/Journal canadien d’anesthésie
- Volume: 67
- Issue: Supplement 1
- Pages: 40-41
- Publisher: Springer Nature
- Date: 2020
Keywords
- Hypernatremia
- Diagnostic Approaches
- University Health Network Hospitals
Citation
Sarwar, S., Shafiee, M. A., Dastgheib, M., Hajighadimi, S., Ghafarian, H., & Rokni, H. (2020). Current Diagnostic Approaches to Patients with Hypernatremia at University Health Network Hospitals. Canadian Journal of Anesthesia/Journal canadien d’anesthésie, 67(Supplement 1), 40-41. https://doi.org/10.1007/s12630-019-01552-z