The Early Endocrine Stress Response in Experimental Subarachnoid Hemorrhage

Association between serum sodium levels within 24 h of admission and all-cause mortality in critically ill patients with non-traumatic subarachnoid hemorrhage: a retrospective analysis of the MIMIC-IV database

Objective

The study aimed to evaluate the relationship between serum sodium and mortality in critically ill patients with non-traumatic subarachnoid hemorrhage.

Methods

This is a retrospective investigation of critically ill non-traumatic patients with subarachnoid hemorrhage (SAH) utilizing the MIMIC-IV database. We collected the serum sodium levels at admission and determined the all-cause death rates for the ICU and hospital. We employed a multivariate Cox proportional hazard regression model and Kaplan-Meier survival curve analysis to ascertain the relationship between serum sodium and all-cause mortality. In order to evaluate the consistency of correlations, interaction and subgroup analyses were also conducted.

Results

A total of 864 patients with non-traumatic SAH were included in this study. All-cause mortality in the ICU and hospital was 32.6% (282/864) and 19.2% (166/864), respectively. Sodium levels at ICU admission showed a statistically significant J-shaped non-linear relationship with ICU and hospital mortality (non-linear P-value < 0.05, total P-value < 0.001) with an inflection point of ~141 mmol/L, suggesting that mortality was higher than normal serum sodium levels in hypernatremic patients. Multivariate analysis after adjusting for potential confounders showed that high serum sodium levels (≥145 mmol/L) were associated with an increased risk of all-cause mortality in the ICU and hospital compared with normal serum sodium levels (135-145 mmol/L), [hazard ratio (HR) = 1.47, 95% CI: 1.07-2.01, P = 0.017] and (HR = 2.26, 95% CI:1.54-3.32, P < 0.001). Similarly, Kaplan-Meier (K-M) survival curves showed lower survival in patients with high serum sodium levels. Stratified analysis further showed that the association between higher serum sodium levels and hospital all-cause mortality was stronger in patients aged < 60 years with a hospital stay of <7 days.

Conclusion

High serum sodium levels upon ICU admission are related to higher ICU and hospital all-cause mortality in patients with non-traumatic SAH. A new reference is offered for control strategies to correct serum sodium levels.

Correlation between clinical severity and extent of autonomic cardiovascular impairment in the acute phase of subarachnoid hemorrhage

Background and aim

To assess associations between clinical severity and possible dysfunction of autonomic cardiovascular modulation within the acute phase after spontaneous subarachnoid hemorrhage (SAH).

Methods

In this prospective observational study, in 51 patients with spontaneous SAH, Hunt-and-Hess scores (H&H) were assessed and cardiovascular autonomic modulation was monitored within 24 h after SAH-onset. From 5 min time-series of R–R-intervals (RRI) and blood-pressure (BP) recordings, we calculated autonomic parameters including time-domain [RRI-coefficient-of-variation (RRI-CV) and square-root-of-the-mean-squared-differences-of-successive-RRIs (RMSSD)] and frequency-domain parameters [low- and high-frequency-powers of RRI- and BP-modulation (RRI-LF-, RRI-HF-, SBP-LF-powers) and RRI-total-powers]. Data were compared to those of 20 healthy volunteers.

Results

RRI- and BP-values did not differ between groups. Yet, parameters of sympathetic (RRI-LF-powers 141.0 (18.9–402.4) ms² vs 442.3 (246.8–921.2) ms², p = 0.001) and total autonomic modulation (RRI-CV 2.4 (1.2–3.7) ms² vs 3.7 (3.1–5.3) ms², p = 0.001) were significantly lower in patients than in controls. Subgroup analyses (patients with H&H < 3 vs H&H ≥ 3) and Spearman-rank-correlations revealed increasing loss of sympathetic (RRI-LF-powers 338.6 (179.7–710.4) ms² vs 72.1 (10.1–175.9) ms², p = 0.001, rho = − 0.524) and total autonomic modulation (RRI-CV 3.5 (2.3–5.4) ms² vs 1.6 (1.0–2.8) ms², p < 0.001, rho = − 0.519) with higher H&H-scores. Multiple-logistic-regression underlined the significant influence of H&H-scores on sympathetic (RRI-LF-powers, p = 0.033) and total autonomic modulation (RRI-CV, p = 0.040) compared to possible confounders (e.g., age, intubation).

Conclusion

Within the acute phase, spontaneous SAH induces a decrease in sympathetic and total autonomic cardiovascular modulation. Higher H&H-scores were associated with increasing autonomic dysfunction and may therefore augment the risk of cardiovascular complications and poor clinical outcome.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11220-w.

Early Serum Biomarkers for Intensive Care Unit Treatment within the First 24 Hours in Patients with Intracerebral Hemorrhage

BACKGROUND

 The prognostic significance of serum biomarkers in patients with intracerebral hemorrhage (ICH) is not well investigated concerning inhospital mortality (IHM) and cardiopulmonary events within the first 24 hours of intensive care unit (ICU) treatment. The influence of troponin I (TNI) value and cortisol value (CV) on cardiopulmonary events within the first 24 hours of ICU treatment was reported in subarachnoid hemorrhage patients, but not in ICH patients up to now. The aim of this study was to investigate the role of early serum biomarkers on IHM and TNI value and CV on cardiopulmonary events within the first 24 hours of ICU treatment.

PATIENTS AND METHODS

 A total of 329 patients with spontaneous ICH were retrospectively analyzed. Blood samples were taken on admission to measure serum biomarkers. The TNI value and CV were defined as biomarkers for cardiopulmonary stress. Demographic data, cardiopulmonary parameters, including norepinephrine application rate (NAR) in microgram per kilogram per minute and inspiratory oxygen fraction (FiO₂) within the first 24 hours, and treatment regime were analyzed concerning their impact on ICU treatment and in hospital outcome. Binary logistic analysis was used to identify independent prognostic factors for IHM.

RESULTS

 Patients with initially nonelevated CVs required higher NAR (p = 0.01) and FiO₂ (p = 0.046) within the first 24 hours of ICU treatment. Lower cholinesterase level (p = 0.004), higher NAR (p = 0.002), advanced age (p < 0.0001), larger ICH volume (p < 0.0001), presence of intraventricular hemorrhage (p = 0.007) and hydrocephalus (p = 0.009), raised level of C-reactive protein (p = 0.024), serum lactate (p = 0.003), and blood glucose (p = 0.05) on admission were significantly associated with IHM. In a multivariate model, age (odds ratio [OR]: 1.055; 95% confidence interval [CI]: 1.026-1.085; p < 0.0001), ICH volume (OR: 1.016; CI: 1.008-1.025; p < 0.0001), and Glasgow Coma Scale (GCS) score (OR: 0.680; CI: 0.605-0.764; p < 0.0001) on admission as well as requiring NAR (OR: 1.171; CI: 1.026-1.337; p = 0.02) and FiO₂ (OR: 0.951; CI: 0.921-0.983, p = 0.003) within the first 24 hours were independent predictors of IHM.

CONCLUSION

 Higher levels of C-reactive protein, serum lactate, blood glucose, and lower cholinesterase level on admission were significantly associated with IHM. Patients with initially nonelevated CVs required higher NAR and FiO₂ within the first 24 hours of ICU treatment. Furthermore, requiring an NAR > 0.5 µg/kg/min or an FiO₂ > 0.21 were identified as additional independent predictors for IHM. These results could be helpful to improve ICU treatment in ICH patients.

Relevance of Porcine Stroke Models to Bridge the Gap from Pre-Clinical Findings to Clinical Implementation

In the search of animal stroke models providing translational advantages for biomedical research, pigs are large mammals with interesting brain characteristics and wide social acceptance. Compared to rodents, pigs have human-like highly gyrencephalic brains. In addition, increasingly through phylogeny, animals have more sophisticated white matter connectivity; thus, ratios of white-to-gray matter in humans and pigs are higher than in rodents. Swine models provide the opportunity to study the effect of stroke with emphasis on white matter damage and neuroanatomical changes in connectivity, and their pathophysiological correlate. In addition, the subarachnoid space surrounding the swine brain resembles that of humans. This allows the accumulation of blood and clots in subarachnoid hemorrhage models mimicking the clinical condition. The clot accumulation has been reported to mediate pathological mechanisms known to contribute to infarct progression and final damage in stroke patients. Importantly, swine allows trustworthy tracking of brain damage evolution using the same non-invasive multimodal imaging sequences used in the clinical practice. Moreover, several models of comorbidities and pathologies usually found in stroke patients have recently been established in swine. We review here ischemic and hemorrhagic stroke models reported so far in pigs. The advantages and limitations of each model are also discussed.

Supportive hand-holding attenuates pupillary responses to stress in adult couples

BACKGROUND

Social relationships, particularly marriage, have been shown to ameliorate the potentially pathogenic impact of stressful events but prior research has been mostly aimed at downstream effects, with less research on real-time reactivity. Pupillometry is an innovative procedure that allows us to see the effects of acute stress in real time. The muscles that control pupil size are linked to the autonomic nervous system, so that when stressed, the pupils dilate; this occurs within 200ms. This quick response allows us to see the immediate effects of acute stress on the autonomic nervous system (ANS), and the real-time effects of social support in buffering stress.

PURPOSE

The purpose of this study is to examine the dampening effects of received social support on the ANS's pupillary response.

METHODS

Eighty individuals (40 couples) were randomly assigned to either a spousal support (i.e., spouse hand-holding) or non-support condition (i.e., alone) and administered a Stroop task while pupil dilation was measured.

RESULTS

The Stroop task elicited a stress reaction in terms of pupil dilation in response to the incongruent task trials. Participants in the support condition showed accelerated habituation to the stress task (p < .001), and less pupil reactivity (p < .001) providing evidence for buffering effects of social support via spousal presence and hand-holding.

CONCLUSIONS

These results reveal the speed at which stress-buffering occurs, suggesting that pupillometry could be a good method to address the immediate dampening effects of social support.

Serum glucose/potassium ratio as a clinical risk factor for aneurysmal subarachnoid hemorrhage

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (SAH) can result in poor outcomes, and biomarkers for predicting poor prognosis have not yet been established. The aim of this study was to clarify the significance of the serum glucose/potassium ratio for predicting the prognosis of aneurysmal SAH.

METHODS

The authors retrospectively reviewed the records of 565 patients with aneurysmal SAH between 2006 and 2016. The patient group comprised 208 men and 357 women (mean age 61.5 years, range 10-95 years). A statistical analysis was conducted of the clinical and laboratory risk factors of poor outcome, including the serum glucose/potassium ratio.

RESULTS

On estimation of the initial assessment using Hunt and Kosnik (H-K) grading, 233 patients (41.2%) were classified as the severe SAH group (H-K Grade IV or V). There were significant correlations between the severe SAH group and serum glucose/potassium ratio (p < 0.0001). Serum glucose/potassium ratio was elevated in an H-K grade-dependent manner (Spearman's r = 0.5374, p < 0.0001). With the estimation of the Glasgow Outcome Scale (GOS) score at discharge, 355 patients (62.8%) were classified as poor outcome (GOS score 1-3). The serum glucose/potassium ratio was elevated in a GOS score at discharge-dependent manner (Spearman's r = 0.4006, p < 0.0001), and was significantly elevated in the poor outcome group compared with the good outcome group (GOS score 4 or 5; p = 0.0245). There were significant correlations between poor outcome and serum glucose/potassium ratio (p < 0.0001), age (p < 0.0001), brain natriuretic peptide levels (p = 0.011), cerebral infarction due to vasospasm (p < 0.0001), and H-K grade (p < 0.0001). Multivariate logistic regression analyses showed significant correlations between poor outcome and serum glucose/potassium ratio (p = 0.009).

CONCLUSIONS

In this study, the serum glucose/potassium ratio of patients with aneurysmal SAH at admission was significantly correlated with H-K grade and GOS score at discharge. Therefore, this ratio was useful for predicting prognosis of aneurysmal SAH, especially in severe cases.