Delayed symptomatic hyponatremia in transsphenoidal surgery: Systematic review and meta-analysis of its incidence and prevention with water restriction

Emergency department visits following endoscopic skull base surgery: An opportunity for improvement

BACKGROUND

Readmissions are major healthcare expenditures, key hospital metrics, and are often preceded by an evaluation in the emergency department (ED). The purpose of this study was to analyze ED visits within 30 days of endoscopic skull base surgery (ESBS), risk factors for readmission once in the ED, and ED-related evaluation and outcomes.

METHODS

Retrospective review from January 2017 to December 2022 at a high-volume center of all ESBS patients who presented to the ED within 30 days of surgery.

RESULTS

Of 593 ESBS cases, 104 patients (17.5%) presented to the ED following surgery within 30 days, with a median presentation of 6 days post-discharge (IQR 5-14); 54 (51.9%) patients were discharged while 50 (48.1%) were readmitted. Readmitted patients were significantly older than discharged patients (median 60 years, IQR 50-68 vs. 48 years, 33-56; p < 0.01). Extent of ESBS was not associated with readmission or discharge from the ED. The most common discharge diagnoses were headache (n = 13, 24.1%) and epistaxis (n = 10, 18.5%); the most common readmitting diagnoses were serum abnormality (n = 15, 30.0%) and altered mental status (n = 5, 10.0%). Readmitted patients underwent significantly more laboratory testing than discharged patients (median 6, IQR 3-9 vs. 4, 1-6; p < 0.01).

CONCLUSIONS

Approximately half of patients who presented to the ED following ESBS were discharged home but underwent significant workup. Follow-up within 7 days of discharge, risk-stratified endocrine care pathways, and efforts to address the social determinants of health may be considered to optimize postoperative ESBS care.

Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: Clinical recommendations on the perioperative management of pituitary tumors

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7%-14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up.

Executive summary of the expert consensus document from the Spanish Society of Neurosurgery and the Spanish Society of Endocrinology and Nutrition: clinical recommendations on the perioperative management of pituitary tumors

Pituitary tumors (PT) account for 15% of intracranial tumors affect 10.7-14.4% of the population although the incidence of clinically relevant PT is 5.1 cases/100,000 inhabitants. Surgical treatment is indicated in PTs with hormone hypersecretion (except for prolactin-producing PTs) and those with local compressive or global neurological symptoms. Multidisciplinary care, is essential for patients with PTs, preferably delivered in a center of excellence and based on a well-defined care protocol. In order to facilitate and standardize the clinical procedures for this type of tumor, this document gathers the positioning of the Neuroendocrinology Knowledge Area of the Spanish Society of Endocrinology and Nutrition (SEEN) and the Spanish Society of Neurosurgery (SENEC) on the management of patients with PTs and their preoperative, surgical and postoperative follow-up.

Syndrome of Inappropriate Antidiuresis: From Pathophysiology to Management

Hyponatremia is the most common electrolyte disorder, affecting more than 15% of patients in the hospital. Syndrome of inappropriate antidiuresis (SIAD) is the most frequent cause of hypotonic hyponatremia, mediated by nonosmotic release of arginine vasopressin (AVP, previously known as antidiuretic hormone), which acts on the renal V2 receptors to promote water retention. There are a variety of underlying causes of SIAD, including malignancy, pulmonary pathology, and central nervous system pathology. In clinical practice, the etiology of hyponatremia is frequently multifactorial and the management approach may need to evolve during treatment of a single episode. It is therefore important to regularly reassess clinical status and biochemistry, while remaining alert to potential underlying etiological factors that may become more apparent during the course of treatment. In the absence of severe symptoms requiring urgent intervention, fluid restriction (FR) is widely endorsed as the first-line treatment for SIAD in current guidelines, but there is considerable controversy regarding second-line therapy in instances where FR is unsuccessful, which occurs in around half of cases. We review the epidemiology, pathophysiology, and differential diagnosis of SIAD, and summarize recent evidence for therapeutic options beyond FR, with a focus on tolvaptan, urea, and sodium-glucose cotransporter 2 inhibitors.

Machine learning models predict delayed hyponatremia post-transsphenoidal surgery using clinically available features

PURPOSE

Delayed hyponatremia (DHN), a unique complication, is the leading cause of unexpected readmission after pituitary surgery. Therefore, this study aimed to develop tools for predicting postoperative DHN in patients undergoing endoscopic transsphenoidal surgery (eTSS) for pituitary neuroendocrine tumors (PitNETs).

METHODS

This was a single-center, retrospective study involving 193 patients with PitNETs who underwent eTSS. The objective variable was DHN, defined as serum sodium levels < 135 mmol/L at ≥ 1 time between post operative days 3 and 9. We trained four machine learning models to predict this objective variable using the clinical variables available preoperatively and on the first postoperative day. The clinical variables included patient characteristics, pituitary-related hormone levels, blood test results, radiological findings, and postoperative complications.

RESULTS

The random forest (RF) model demonstrated the highest (0.759 ± 0.039) area under the curve of the receiver operating characteristic curve (ROC-AUC), followed by the support vector machine (0.747 ± 0.034), the light gradient boosting machine (LGBM: 0.738 ± 0.026), and the logistic regression (0.710 ± 0.028). The highest accuracy (0.746 ± 0.029) was observed in the LGBM model. The best-performing RF model was based on 24 features, nine of which were clinically available preoperatively.

CONCLUSIONS

The proposed machine learning models with pre- and post-resection features predicted DHN after the resection of PitNETs.

Delayed postoperative hyponatremia in patients with acromegaly: incidence and predictive factors

PURPOSE

Delayed postoperative hyponatremia (DPH) is a unique complication of transsphenoidal surgery (TSS) in pituitary tumors. Growth hormone (GH) enhances renal sodium reabsorption; however, the association between postoperative GH reduction and DPH in acromegaly is unclear. This study was performed to clarify the incidence of and the predictive factors for DPH in patients with acromegaly who underwent TSS.

METHODS

Ninety-four patients with active acromegaly were examined retrospectively. During the postoperative course, patients with serum sodium levels ≤ 134 mEq/L were classified into the DPH group. We compared basic clinical characteristics, tumor characteristics, and preoperative and postoperative examination findings between the DPH and non-DPH groups.

RESULTS

DPH occurred in 39 patients (41.5%), and the lowest serum sodium levels were generally observed during postoperative days (PODs) 7-9. They needed a 3-day longer hospital stay than those without DPH. The DPH group had lower preoperative body weight and body mass index. In addition, a transient increase in body weight during PODs 5-7 occurred with a transient decrease in urinary volume in the DPH group. Preoperative and postoperative GH and insulin-like growth factor-1 levels did not differ between the two groups.

CONCLUSION

The findings suggested that lower preoperative weight and a postoperative transient gain in body weight are associated with an increased risk of DPH in acromegaly patients undergoing transsphenoidal surgery.

Disorders of Salt and Water Balance After Pituitary Surgery

Transsphenoidal surgery is the first-line treatment for many clinically significant pituitary tumors and sellar lesions. Although complication rates are low when performed at high-volume centers, disorders of salt and water balance are relatively common postoperatively. Both, or either, central diabetes insipidus (recently renamed arginine vasopressin deficiency - AVP-D), caused by a deficiency in production and/or secretion of arginine vasopressin, and hyponatremia, most commonly secondary to the syndrome of inappropriate antidiuresis, may occur. These conditions can extend hospital stay and increase the risk of readmission. This article discusses common presentations of salt and water balance disorders following pituitary surgery, the pathophysiology of these conditions, and their diagnosis and management.

Prevention of Hyponatremia After Transsphenoidal Surgery: A Systematic Review

Context: Pituitary adenomas are amongst the most common tumors with a low mortality rate compared to other intracranial malignancies. Delayed hyponatremia (DH) is a common finding after transsphenoidal resection (TSS), which is the basis for the management of these tumors. Although DH is one of the leading causes of readmission after TSS, no unified guidelines exist with regard to the prevention of this electrolyte disturbance. Objectives: This study aims to evaluate and compare existing preventive protocols for DH in order to identify and signify their common grounds. Methods: After a search in electronic databases, including PubMed (NCBI), Embase, Scopus, and Google Scholar with the keywords of “pituitary adenoma,” “hyponatremia,” “transsphenoid surgery”, “water electrolyte balance,” “patient readmission", six original articles were included in the study. Results: We found that a protocol that both identifies groups susceptible to DH (males, older individuals, and those with a lower BMI) and consists of fluid restriction, sodium supplementation, and regular serum sodium monitoring could be utilized to prevent DH in patients with pituitary adenomas after TSS. Conclusions: Further studies with a larger sample size must be conducted to compare existing protocols for preventing DH and also investigate post-surgery optimal fluid-restricted diets and corticosteroid therapy in these patients.