The role of systemic inflammatory response, hypermetabolism, and wound treatment and repair in hypernatremia of severely burned patients

Hypernatremia represents a critical complication in patients with severe burns. This study aims to further investigate the etiology, clinical features, and therapeutic strategies for hypernatremia in this patient population. We conducted daily measurements of serum sodium (Na), chloride (Cl), potassium (K), urea nitrogen (Un), creatinine (Cr) concentrations, procalcitonin (PCT) levels, and serum osmolality in 23 patients with total burn area ≥ 90% TBSA. Additionally, 24-hour urine output was recorded, and urinary excretion of Na, Cl, K, Un, and Cr was analyzed. Changes in wound status and systemic inflammatory response were also monitored. After wound treatment and repair, serum and 24-hour urine test indicators were reassessed. Patients were categorized into two groups based on their serum Na concentration: the normal group (N group) with serum Na ≤ 149 mmol/L, and the hypernatremia group (H group) with serum Na ≥ 150 mmol/L. Among the 10 patients in the H group, serum Na, Un, PCT, and serum osmolality were 158.09 ± 5.74 mmol/L, 27.43 ± 9.10 mmol/L, 1.40 ± 0.94 ng/mL, and 323.53 ± 8.46 mosm/kg, respectively, all significantly higher than those in the N group ( P < 0.05). Urinary Na excretion in the H group was 105.95 ± 44.81 mmol/24 h, significantly lower than in the N group (p < 0.05). Urinary excretion of Un, Cr, and K increased in the H group, with Un excretion reaching 1339.08 ± 350.43 mmol/24 h, significantly higher than in the N group ( P < 0.05). The H group exhibited signs of wound eschar dissolution and exacerbated systemic inflammatory response. Within 2 days post-wound treatment and repair, serum Na levels in the H group normalized, with 8 out of 10 patients achieving full recovery. All 13 patients in the N group recovered fully. Some severely burned patients may experience increased systemic inflammatory response, leading to enhanced high catabolic metabolism, increased production and excretion of Un, and reduced urinary Na excretion, resulting in hypernatremia. Reduced urinary Na excretion is a significant cause of hypernatremia in severely burned patients. The primary basic treatment measure should be to treat and repair the wound, thereby controlling systemic inflammatory response, reducing high metabolism, and promoting urinary sodium excretion. • A clinical observation was conducted on patients with burn area ≥ 90% TBSA. • Reduced urinary sodium excretion is an important cause of hypernatremia. • Wound treatment and repair are fundamental measures for treating hypernatremia.