Impact of perioperative hyponatremia in children: A narrative review

Postoperative hyponatremia in neonates with esophageal atresia and tracheoesophageal fistula receiving restricted hypotonic fluids

Background

During the postoperative course following neonatal surgery, several stimuli like respiratory distress, pain, and stress cause the release of the antidiuretic hormone which can induce hyponatremia. This hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion (SIADH) in neonates can lead to neurologic impairment and in severe cases can cause significant morbidity and mortality. Lung involvement in neonates undergoing TEF makes this subset of patients vulnerable to this entity because most of them are sick and require ventilation in the postoperative period. The incidence of postoperative hyponatremia following neonatal surgery has not been studied vastly. To the best of our knowledge, this is the first prospective study that has analyzed the incidence of postoperative hyponatremia in this vulnerable population.

Methods

Prospective observational study to assess the incidence of postoperative hyponatremia in neonates with esophageal atresia and tracheoesophageal fistula (EA and TEF) receiving restricted hypotonic fluids. As per the unit policy N/4 5% D is given in the postoperative period. Most neonatal units follow a protocol in which fluid is hiked daily to reach 150 ml/kg/day in 5–7 days. However, in our neonatal surgical unit a protocol to restrict the maintenance fluid at 100 ml/kg/day irrespective of day of life is followed.

Results

Out of a total of 90 neonates (270 sodium measurements), we identified 16 with hyponatremia (11%). Most of the neonates had mild hyponatremia(130–135 meq/l). The incidence of moderate and severe hyponatremia was low.

Conclusion

Postoperative restriction of fluids especially in neonates who are at a high risk for developing SIADH can lead to decreased incidence of severe hyponatremia.

Postoperative dysnatremia in infants after open-heart surgery occurs frequently and is associated with prolonged intensive care length of stay

BACKGROUND

Dysnatremia after surgery for congenital heart disease (CHD) is well known and has been associated with prolonged pediatric intensive care unit length of stay (PICU-LOS). Fluctuations in plasma sodium levels occur perioperatively. The primary aim of the study was to evaluate the occurrence of dysnatremia during the first 48 h after surgery and whether it was associated with PICU-LOS. The secondary aim was to evaluate if the degree of sodium fluctuations was associated with PICU-LOS.

METHODS

A retrospective observational, single-center study including infants undergoing surgery for CHD. The highest and lowest plasma sodium value was registered for the prespecified time periods. PICU-LOS was analyzed in relation to the occurrence of dysnatremia and the degree of plasma sodium fluctuations. The occurrence of dysnatremia was evaluated in relation to surgical procedure and fluid administration.

RESULTS

Two hundred and thirty infants who underwent 249 surgical procedures were included. Dysnatremia developed in more than 60% within 48 h after surgery. Infants with normonatremia had a 40%-50% shorter PICU-LOS among children in RACHS-1 category 3-6, compared with infants developing either hypo- or hyper-/hyponatremia within 48 h after surgery (p = .006). Infants who had a decline of plasma sodium >11 mmol/L had almost double the PICU-LOS compared to those with a decline of <8 mmol/L.

CONCLUSION

Dysnatremias were common after surgery for CHD and associated with prolonged PICU-LOS. The degree of decline in plasma sodium was significantly associated with PICU-LOS. Fluid administration both in terms of volume and components (blood products and crystalloids) as well as diuresis were related to the occurrence of dysnatremias.

Evaluating a standardized protocol for the management of diabetes insipidus in pediatric neurosurgical patients

OBJECTIVES

Central diabetes insipidus (DI) is a known complication following surgical resection of a suprasellar mass. There are limited data analyzing the outcomes of a standardized protocol for the management of postoperative DI in the pediatric population. We sought to fill this gap and hypothesized that utilizing a standardized protocol for fluid management (3-bag system) would reduce serum sodium fluctuations in the postoperative period after suprasellar surgery.

METHODS

A retrospective chart review was performed. Patients were identified with the following criteria: age ≤ 18 years, undergoing a surgical procedure for suprasellar mass that also had postoperative DI. The primary outcome was the variability in serum sodium during the first 48 h and between 48 and 120 h postoperatively.

RESULTS

There were 21 encounters pre-protocol and 22 encounters post-protocol for neurosurgical procedures. Use of the standardized protocol was associated with a lower range of sodium within 48 h postoperatively (p=0.065) and 83% lower odds of hypernatremia (Na>150 mmol/L) within 48 h postoperatively (CI 0.039-0.714) after controlling for age, gender, and prior DI diagnosis. History of DI conferred a lower risk of hypernatremia as well as less sodium fluctuation within 48 h postoperatively. Younger patients, those <9.7 years of age were associated with increased risk of hyponatremia and greater sodium fluctuations during the postoperative period.

CONCLUSIONS

In patients with postoperative DI after suprasellar surgery, using a standardized protocol for fluid management (3-bag system) appears to reduce serum sodium variability in the first 48 h after surgery.

Factors affecting blood glucose and serum sodium level with intraoperative infusion of 1% dextrose in ringer's lactate in neonates undergoing surgery

Context:

Under anesthesia, blood glucose level in term neonates varies widely due to stress induced glucose mobilisation due to various factors. Postoperative hyponatremia occurs with intraoperative infusion of large volume of hypotonic fluid. There is a growing consensus on the intraoperative use of 1–4% glucose containing isotonic fluid in them.

Aims:

To know the relation of duration of surgery, infusion rate, fluid bolus, blood transfusion with blood glucose level and effect on serum sodium level with intraoperative 1% dextrose ringer's lactate (1% DRL) in neonates undergoing surgery.

Settings and Design:

Prospective single-center study in tertiary institute.

Subjects and Methods:

A total of 100 neonates undergoing various surgeries under general anesthesia with or without caudal anaesthesia were included. 1% DRL was used as maintenance and replacement fluid intraoperatively. Blood glucose level at hourly interval throughout surgery and serum sodium concentration before and after infusion was documented.

Statistical Analysis Used:

Student's t test (two tailed, independent) has been used for statistical analysis.

Results:

After the infusion of 1% DRL during surgery, mean blood sugar levels were increased above the base line in all neonates at successive hourly interval. Serum sodium levels remained within physiological range in all neonates.

Conclusion:

Intraoperative hyperglycemia is more obvious with higher intravenous fluid infusion rate, prolonged duration of surgery, and requirement of fluid bolus as well as blood transfusion intraoperatively. Use of 1% DRL in neonates undergoing surgery is effective in preventing dysnatremia.