Estimation of sodium and chloride storage in critically ill patients: a balance study

Enteral free water vs. parenteral dextrose 5% in water for the treatment of hypernatremia in the intensive care unit: a retrospective cohort study from a mixed ICU

PURPOSE

Effective treatment options for patients with hypernatremia are limited. Free water administration (parenterally or enterally) is the mainstay of treatment but the impact of each strategy on lowering serum sodium (Na) is not known. The purpose of the study was thus to assess the effectiveness of enteral free water vs. parenteral dextrose 5% in water (D5W) in treating ICU-acquired hypernatremia.

METHODS

An electronic medical record-based, retrospective cohort study was conducted in a 30-bed mixed medical-surgical intensive care unit (ICU) in Japan. All adult patients admitted to the ICU from August 2017 to July 2021 were reviewed. After a 2-step exclusion, patients who stayed in the ICU ≥ 24 h and received either or both treatments for ICU-acquired hypernatremia (Na ≥ 145 mEq/L) constituted the study cohort. The primary outcome was a change in serum Na during the 24 h before treatment each day (ΔNa); the secondary outcomes were gastrointestinal complications, serum glucose levels, ICU/hospital mortality, ICU/hospital length of stay, and the duration of mechanical ventilation. Repeated measurements on each patient were addressed using a generalized estimated equation (GEE) for multiple linear regression analysis. Analysis was conducted with R version 4.0.3.

RESULTS

In total, 256/6596 (131: D5W, 125: enteral free water) patients were analyzed. Median treatment lasted 6 days [3-17] for the D5W group vs 7 days [3-14] for the enteral free water group with a total median daily treatment volume of 799 [IQR 299-1221] mL vs. 400 [IQR 262-573] mL. GEE multiple linear regression analysis showed an estimated mean ΔNa per liter of treatment fluid of - 2.25 [95% CI - 2.76 to - 1.74] mEq/L per liter of parenteral D5W vs. - 1.91 mEq decrease [95% CI - 2.75 to - 1.07] per liter of enteral free water. Hydrochlorothiazide was the only medication associated with a statistically significant negative ΔNa by- 0.89 [- 1.57 to - 0.21] mEq/L. There were no significant inter-group differences for secondary outcomes.

CONCLUSIONS

These results suggest that both enteral free water and parenteral D5W are effective for treating ICU-acquired hypernatremia. Parenteral D5W was slightly more effective than enteral free water to lower serum Na levels in patients with ICU-acquired hypernatremia.

TRIAL REGISTRATION

Not applicable.

Electrolytes, albumin and acid base equilibrium during laparoscopic surgery

BACKGROUND

Surgery, causing inflammation, disrupts endothelial permeability leading to movement of fluids and albumin across the vascular barrier. Fluid therapy for restoring circulatory homeostasis may lead to positive fluid balance which has been shown to increase morbidity and mortality in surgical patients. The current investigation aims to describe physio-pathological changes in circulating albumin, fluid and electrolyte balance, and acidbase equilibrium in a cohort of patients undergoing laparoscopic surgery under general anesthesia.

METHODS

Single-center prospective observational study. Patients undergoing laparoscopic colorectal surgery were screened for eligibility.. Before surgery the baseline fasting conditions were homogenized. Hemoglobin, urinary and plasmatic were collected before surgery and then at pre-defined timepoints. Albumin/Creatinine ratio was measured before and after surgery. Expected and actual circulating Sodium concentrations were compared according to a physiological theoretical model. Assessment and quantification of changes in major electrolytes, albumin and acid-base balance was defined as the primary outcome of the study.

RESULTS

38 patients were enrolled in the protocol. Patients had a positive electrolytes (Na+ 295 [244-375] mmol, Cl- 234 [195-295] mmol, K+ 16.8 [12.0-21.4] mmol) and fluid balance (2165 [1727-2728] ml). The positive fluid balance was associated with stable chloride (105 [103-107], end study vs 103 [102-106] mmol/L, baseline, p=ns) and potassium (4.2 [3.8-4.4], end study vs 4.1 [3.6-4.4] mmol/L, baseline, p=ns) levels, but sodium concentrations decreased over time (138 [137-140], end study vs 139 [138-141] mmol/L, baseline, p<0.05). The Albumin/Creatinine ratio was higher at the end of surgery 134 [61-267] vs 7 [4-14], p<0.001).

CONCLUSIONS

Data from patients undergoing colorectal laparoscopic surgery showed a positive fluid balance, decreased circulating albumin and increased albuminuria. A positive sodium balance was not always associated with an increase in sodium plasma concentration.

ICU acquired hypernatremia treated by enteral free water - A retrospective cohort study

PURPOSE

ICU acquired hypernatremia (IAH) is associated with increased morbidity and mortality, however treatment remains controversial. This study aims to determine the effect of enteral free water suppletion in patients with IAH.

MATERIALS AND METHODS

Retrospective single center study in a tertiary ICU.

INCLUSION CRITERIA

patients with IAH and treatment with enteral free water.

EXCLUSION CRITERIA

patients with renal replacement therapy, diabetic ketoacidosis or hyperosmolar hyperglycaemic state.

PRIMARY OUTCOME

change in plasma sodium (in mmol/l) after 5 days treatment. Responders were defined as patients with a decrease in sodium level of 5 mmol/l or more.

RESULTS

In total 382 consecutive patients were included. The median sodium level at the start of water therapy was 149 mmol/l (IQR 147-150). The median volume of enteral water was 4423 ml (IQR 3349-5379 ml) after 5 days and mean sodium decrease was 1.87 mmol/l (SD 4.84). There was no significant correlation between the volume of enteral water and sodium decrease (r² = 0.01).

CONCLUSIONS

Treatment with enteral free water did not result in a clinically relevant decrease in serum sodium level in patients with IAH. In addition, the volume of enteral free water and the use of diuretics was unrelated with sodium change over 5 days.