Increased Serum Sodium Values in Brain-dead Donor's Influences Its Long-term Kidney Function

Relationship between Hyponatremia and Peripheral Neuropathy in Patients with Diabetes

OBJECTIVES

Hyponatremia is a common complication of diabetes. However, the relationship between serum sodium level and diabetic peripheral neuropathy (DPN) is unknown. This study was aimed at investigating the relationship between low serum sodium level and DPN in Chinese patients with type 2 diabetes mellitus.

METHODS

A retrospective study was performed on 1928 patients with type 2 diabetes between 2010 and 2018. The multivariate test was used to analyze the relationship between the serum sodium level and the nerve conduction function. A restricted cubic spline was used to flexibly model and visualize the relationship between the serum sodium level and DPN, followed by logistic regression with adjustment.

RESULTS

As the serum sodium level increased, the prevalence of DPN had a reverse J-curve distribution with the serum sodium levels (69.6%, 53.7%, 49.6%, 43.9%, and 49.7%; P = 0.001). Significant differences existed between the serum sodium level and the motor nerve conduction velocity, sensory nerve conduction velocity, part of compound muscle action potential, and sensory nerve action potential of the participants. Compared with hyponatremia, the higher serum sodium level was a relative lower risk factor for DPN after adjusting for several potential confounders (OR = 0.430, 95%CI = 0.220-0.841; OR = 0.386, 95%CI = 0.198-0.755; OR = 0.297, 95%CI = 0.152-0.580; OR = 0.376, 95%CI = 0.190-0.743; all P < 0.05). Compared with low-normal serum sodium groups, the high-normal serum sodium level was also a risk factor for DPN (OR = 0.690, 95%CI = 0.526-0.905, P = 0.007). This relationship was particularly apparent in male participants, those aged <65 years, those with a duration of diabetes of <10 years, and those with a urinary albumin - to - creatinine ratio (UACR) < 30 mg/g.

CONCLUSIONS

Low serum sodium levels were independently associated with DPN, even within the normal range of the serum sodium. We should pay more attention to avoid the low serum sodium level in patients with type 2 diabetes mellitus.

Diabetes Insipidus and Syndrome of Inappropriate Antidiuretic Hormone in Critically Ill Patients

Diabetes insipidus and the syndrome of inappropriate antidiuretic hormone secretion lie at opposite ends of the spectrum of disordered renal handling of water. Whereas renal retention of water insidiously causes hypotonic hyponatremia in syndrome of inappropriate antidiuretic hormone secretion, diabetes insipidus may lead to free water loss, hypernatremia, and volume depletion. Hypernatremia and hyponatremia are associated with worse outcomes and longer intensive care stays. Moreover, pathologies causing polyuria and hyponatremia in patients in intensive care may be multiple, making diagnosis challenging. We provide an approach to the diagnosis and management of these conditions in intensive care patients.

Donor Hypernatremia is Not Related with the Duration of Postoperative Mechanical Ventilation, Primary Graft Dysfunction, or Long-Term Outcome Following Lung Transplantation

BACKGROUND Donor hypernatremia has been associated with reduced graft and recipient survival after heart, liver, kidney, and pancreas transplantation. However, it is unknown what effect donor hypernatremia has on graft and recipient outcomes after lung transplantation. The aim of this study was to investigate the relation of donor hypernatremia with the duration of postoperative mechanical ventilation, the incidence of severe primary graft dysfunction, and survival following lung transplantation. MATERIAL AND METHODS We analyzed all consecutive lung transplantations performed in adult patients at our center between 1995 and 2016. During the study period, donor hypernatremia was not considered a reason to reject lungs for transplantation. Donors were classified into 3 groups: normonatremia (sodium <145 mmol/L), moderate hypernatremia (sodium 145-154 mmol/L), or severe hypernatremia (sodium ≥155 mmol/L). Short-term outcome was defined by the duration of mechanical ventilation and incidence of primary graft dysfunction; long-term outcome was defined by 10-year mortality. RESULTS Donor hypernatremia was recorded in 275 (58%) of the 474 donors. There were no differences in baseline characteristics between the 3 study groups. The duration of mechanical ventilation was similar for all groups (8±25, 7±17, and 9±15 days respectively, P=0.204). Severe primary graft dysfunction was not different between the 3 groups (29%, 26%, 28%, P=0.724). Donor hypernatremia was not associated with (graft) survival, or after correction for potential confounders. CONCLUSIONS Donor hypernatremia was not associated with a worse outcome in lung transplant recipients. Thus, in contrast to solid organ transplantation, donor hypernatremia is not a contraindication for lung transplantation.

Sodium levels of human pancreatic donors are a critical factor for determination of islet efficacy and survival

Organs from hypernatremia (elevated Na+) donors when used for transplantation have had dismal outcomes. However, islet isolation from hypernatremic donors for both transplantation and research applications has not yet been investigated. A retrospective analysis of in vivo and in vitro islet function studies was performed on islets isolated from hypernatremic (serum sodium levels≥160 meq/l) and normal control (serum sodium levels≤155 meq/l) donors. Twelve isolations from 32 hypernatremic and 53 isolations from 222 normal donors were randomly transplanted into diabetic NOD Scid mice. Sodium levels upon pancreas procurement were significantly elevated in the hypernatremia group (163.5±0.6 meq/l) compared with the normal control group (145.9±0.4 meq/l) (P<0.001). The postculture islet recovery rate was significantly lower in the hypernatremia (59.1±3.8%) group compared with the normal (73.6±1.8%) group (P=0.005). The duration of hypernatremia was inversely correlated with the recovery rate (r2=0.370, P<0.001). Furthermore, the percentage of successful graft function when transplanted into diabetic NOD Scid mice was significantly lower in the hypernatremia (42%) group compared with the normal control (85%) group (P<0.001). The ability to predict islet graft function posttransplantation using donor sodium levels and duration of hypernatremia was significant (ROC analysis, P=0.022 and 0.042, respectively). In conclusion, duration of donor hypernatremia is associated with reduced islet recovery postculture. The efficacy of islets from hypernatremia donors diminished when transplanted into diabetic recipients.