Effects of ischemic phrenic nerve root ganglion injury on respiratory disturbances in subarachnoid hemorrhage: an experimental study

Endocrine dysregulation in aneurysmal subarachnoid haemorrhage

INTRODUCTION

Aneurysmal Subarachnoid haemorrhage (aSAH) is one of the most common causes of neurocritical care admission. Consistent evidence has been suggestive of endocrine dysregulation in aSAH. This review aims to provide an up-to-date presentation of the available evidence regarding endocrine dysregulation in aneurysmal subarachnoid haemorrhage.

METHODS

A comprehensive literature search was performed using PubMed database. All available evidence related to endocrine dysregulation in hypothalamic-pituitary hormones, adrenal hormones and natriuretic peptides after aSAH, published since 2010, were reviewed.

RESULTS

There have been reports of varying prevalence of dysregulation in hypothalamic-pituitary and adrenal hormones in aSAH. The cause of this dysregulation and its pattern remain unclear. Hypothalamic-pituitary and adrenal dysregulation have been associated with higher incidence of poor neurological outcome and increased mortality. Whilst there is evidence that long-term dysregulation of these axes may also develop, it appears to be less frequent than the acute-phase dysregulation and transient in pattern. Increased levels of catecholamines have been reported in the hyper-acute phase of aSAH with reported inconsistent correlation with the outcomes and the complications of the disease. There is growing evidence that of a causal link between the endocrine dysregulation and the development of hyponatraemia and delayed cerebral ischaemia, in the acute phase of aSAH. However, the pathophysiological mechanism and pattern of endocrine dysregulation which could be causally associated with these complications still remain debatable.

CONCLUSION

The evidence, mainly from small observational and heterogeneous in methodology studies, is suggestive of adverse effects of the endocrine dysregulation on the outcome and the incidence of complications of the disease. However, the cause of this dysregulation and a pathophysiological mechanism that could link its presence with the development of acute complications and the outcome of the aSAH remain unclear. Further research is warranted to elucidate the clinical significance of endocrine dysregulation in subarachnoid haemorrhage.

Neuropulmonology

Neuropulmonology refers to the complex interconnection between the central nervous system and the respiratory system. Neurologic injury includes traumatic brain injury, hemorrhage, stroke, and seizures, and in each there are far-reaching effects that can result in pulmonary dysfunction. Systemic changes can induce impairment of pulmonary function due to changes in the core structure and function of the lung. The conditions and disorders that often occur in these patients include aspiration pneumonia, neurogenic pulmonary edema, and acute respiratory distress syndrome, but also several abnormal respiratory patterns and sleep-disordered breathing. Lung infections, pulmonary edema - neurogenic or cardiogenic - and pulmonary embolus all are a serious barrier to recovery and can have significant effects on outcomes such as hospital course, prognosis, and mortality. This review presents the spectrum of pulmonary abnormalities seen in neurocritical care.

The impact of L5 dorsal root ganglion degeneration and Adamkiewicz artery vasospasm on descending colon dilatation following spinal subarachnoid hemorrhage: An experimental study; first report

CONTEXT

Somato-sensitive innervation of bowels are maintained by lower segments of spinal cord and the blood supply of the lower spinal cord is heavily dependent on Adamkiewicz artery. Although bowel problems are sometimes seen in subarachnoid hemorrhage neither Adamkiewicz artery spasm nor spinal cord ischemia has not been elucidated as a cause of bowel dilatation so far.

AIMS

The goal of this study was to study the effects Adamkiewicz artery (AKA) vasospasm in lumbar subarachnoid hemorrhage (SAH) on bowel dilatation severity.

SETTINGS AND DESIGN

An experimental rabbit study.

MATERIALS AND METHODS

The study was conducted on 25 rabbits, which were randomly divided into three groups: Spinal SAH (N = 13), serum saline (SS) (SS; N = 7) and control (N = 5) groups. Experimental spinal SAH was performed. After 21 days, volume values of descending parts of large bowels and degenerated neuron density of L5DRG were analyzed.

STATISTICAL ANALYSIS USED

Statistical analysis was performed using the PASW Statistics 18.0 for Windows (SPSS Inc., Chicago, Illinois). Two-tailed t-test and Mann-Whitney U-tests were used. The statistical significance was set at P < 0.05.

RESULTS

The mean volume of imaginary descending colons was estimated as 93 ± 12 cm(3) in the control group and 121 ± 26 cm(3) in the SS group and 176 ± 49 cm(3) in SAH group. Volume augmentations of the descending colons and degenerated neuron density L5DRG were significantly different between the SAH and other two groups (P < 0.05).

CONCLUSION

An inverse relationship between the living neuronal density of the L5DRG and the volume of imaginary descending colon values was occurred. Our findings will aid in the planning of future experimental studies and determining the clinical relevance on such studies.

The harmful effects of subarachnoid hemorrhage on extracerebral organs

Subarachnoid hemorrhage (SAH) is a devastating neurological disorder. Patients with aneurysmal SAH develop secondary complications that are important causes of morbidity and mortality. Aside from secondary neurological injuries, SAH has been associated with nonneurologic medical complications, such as neurocardiogenic injury, neurogenic pulmonary edema, hyperglycemia, and electrolyte imbalance, of which cardiac and pulmonary complications are most common. The related mechanisms include activation of the sympathetic nervous system, release of catecholamines and other hormones, and inflammatory responses. Extracerebral complications are directly related to the severity of SAH-induced brain injury and indicate the clinical outcome in patients. This review provides an overview of the extracerebral complications after SAH. We also aim to describe the manifestations, underlying mechanisms, and the effects of those extracerebral complications on outcome following SAH.