pituitrin and Intracranial-Hypertension

Introduce and evaluate a new model which explains the release of brain antidiuretic hormone (ADH) independent of plasma osmolality.. Systematic review and critical analysis of the professional literature.. Primary electronic database searches using key terms revealed 57,432 hits. Secondary searches with application of specific inclusion and exclusion criteria and manual inspection for completeness reduced the total number of studies to fourteen (N = 14). Twelve (N = 12) studies investigated human subjects in the hospital settings, and two (N = 2) studies investigated animals (rhesus monkeys and dog) under invasive experimental conditions. All fourteen studies included direct or indirect indicators of intracranial pressure (ICP), measurements of plasma ADH, and plasma osmolality or urine osmolality. Findings, in brief, reveal a stable and positive association between increased intracranial pressure (ICP) and increased ADH release, in patients with low or normal blood osmolality. Findings are reliable and reproducible across human and animal populations.. Findings support the proposed model, which explains increase secretion of brain ADH when plasma osmolality is low or within normal limits. Mechanical pressures exerted on hypothalamic nuclei, especially paraventricular and supra-optic nuclei, as a consequence of increased intracranial pressure, produce release of ADH, independent of plasma osmolality. The mechanical pressure model explains release of ADH previously unexplained by traditional plasma osmolality models. Findings have important clinical implications for the medical and surgical management of patients.

Topics: Animals; Female; Humans; Intracranial Hypertension; Intracranial Pressure; Male; Neurophysins; Osmolar Concentration; Protein Precursors; Vasopressins

We examined the link between increased intra-abdominal pressure, intracranial pressure, and vasopressin release as a potential mechanism. Intra-abdominal pressure, produced by abdominal-cavity insufflation with carbon dioxide (CO. Statistically significant elevations (all P ≤ .001) were noted from T. Increased mean arterial pressure, intracranial pressure, and vasopressin release appear to be intermediary steps between increased intra-abdominal pressure and oliguria. Further research is necessary to determine any causative links between these physiological changes.

Topics: Adult; Aged; Female; Gastrectomy; Humans; Intra-Abdominal Hypertension; Intracranial Hypertension; Laparoscopy; Male; Middle Aged; Oliguria; Pneumoperitoneum, Artificial; Prospective Studies; Vasomotor System; Vasopressins; Young Adult

Topics: Blood Pressure; Hemodynamics; Humans; Intracranial Hypertension; Intracranial Pressure; Reflex; Vasopressins

Abdominal compartment syndrome has been linked to detrimental hemodynamic side effects that include increased intracranial pressure and diminished renal function, but the mechanisms behind this continue to be elucidated. In this study, we sought to investigate any direct association between acute elevations in intra-abdominal pressure and intracranial hypertension during experimentally induced abdominal compartment syndrome and between acutely elevated intracranial pressure and the hemodynamic response that might be elicited by a vasopressin-induced Cushing reflex affecting urine osmolality and urine output. The aim of this study is to explain the Cushing reflex and the vasopressin-mediated hemodynamic response to intracranial pressure during acute elevations in intra-abdominal pressure.. We measured intra-abdominal pressure, intrathoracic pressure, optic nerve sheath diameter as an indirect sign of intracranial pressure, vasopressin levels in blood, urine osmolality, and urine output at 4 time points during surgery in 16 patients undergoing sleeve gastrectomy for morbid obesity. Values for the 4 time points were compared by repeated-measures analysis of variance.. More than 50-fold elevations in serum vasopressin paralleled increases in optic nerve sheath diameter, rising throughout prepneumoperitoneum and tapering off afterward, in conjunction with a marked decrease in urine but not serum osmolality. Mean arterial pressure rose transiently during pneumoperitoneum without elevated positive end-expiratory pressure but was not significantly elevated thereafter.. These findings support our hypothesis that the oliguric response observed in abdominal compartment syndrome might be the result of the acutely elevated intra-abdominal pressure triggering increased intrathoracic pressure, decreased venous outflow from the central nervous system, increased intracranial pressure, and resultant vasopressin release via a Cushing reflex.

Topics: Adult; Female; Humans; Intra-Abdominal Hypertension; Intracranial Hypertension; Intracranial Pressure; Male; Middle Aged; Optic Nerve; Pneumoperitoneum, Artificial; Prospective Studies; Ultrasonography; Vasopressins

Case report.. Operating room.. 25YF, ASA IV E who underwent an emergent decompressive craniectomy for refractory intracranial hypertension secondary to acute intracranial hemorhage.. A 25Y caucasian female presented with acute intracranial hemorrhage with intraventricular extension secondary to Moya Moya disease. Post admisison, she underwent an emergent decompressive craniectomy for medically refractory intracranial hypertension. Introperatively (post dural closure and bone flap removal) the patient developed acutely worsening peak and plateau pressures followed by pulseless electrical activity necessitating CPR with epinephrine and Vasopressin before return of circulation before return of circulation. Intraoperative TEE done during return of circulation, was essentially non diagnostic, the patient had normal breath sounds throughout, and non-contributory bronchoscopy findings.. EKG, arterial blood pressure, heart rate, resp. rate, introperative tranesophageal echocardiogram (TEE), Pulse oximetry, serial arterial blood gases, introperative bronchoscopy, ventilatory peak pressures.. A post operative chest CT revealed extensive pneumomediastinum with subcutaneous emphysema. The focussed introperative echocardiogram showed preserved left ventricular function and no evidence of tamponade physiology.. Tension pneumomediastinum was the likely etiologic factor for the acute hemodynamic collapse and should be considered in the differential diagnosis of intraoperative circulatory arrest.

Topics: Adult; Angiography; Bronchoscopy; Cardiopulmonary Resuscitation; Chest Tubes; Computed Tomography Angiography; Decompressive Craniectomy; Diagnosis, Differential; Echocardiography, Transesophageal; Epinephrine; Female; Heart Arrest; Humans; Intracranial Hemorrhages; Intracranial Hypertension; Intraoperative Complications; Mediastinal Emphysema; Moyamoya Disease; Pulmonary Embolism; Respiratory Sounds; Vasoconstrictor Agents; Vasopressins

Head injury frequently results in increased intracranial pressure and brain edema. Investigators have demonstrated that ischemic injury causes an increase in cerebrospinal fluid (CSF) levels of antidiuretic hormone (ADH); increased CSF ADH levels exacerbate cerebral edema, and inhibition of the ADH system with specific ADH antagonists reduces cerebral edema. The current study was designed to test the hypothesis that elevated levels of ADH are present in the CSF of subjects with head injury.. Ventricular CSF and blood samples were taken from 11 subjects with head injury and 12 subjects with no known head trauma or injury. ADH levels were analyzed using radioimmunoassay. Severity of increased intracranial pressure (ICP) was rated in head-injured subjects using a four-point ordinal scale, based on which treatments were necessary to reduce ICP.. Subjects with head injury had higher CSF (3.2 versus 1.2 pg/ml; P<0.02) and plasma (4.1 versus 1.4 pg/ml; P<0.02) levels of ADH than did control subjects. In head-injured subjects, CSF ADH levels positively correlated with severity of ICP.. The results of this study suggest that ADH plays a role in brain edema associated with closed head injury.

Topics: Adult; Aged; Brain Edema; Brain Injuries; Child; Head Injuries, Closed; Humans; Intracranial Hypertension; Male; Middle Aged; Neurophysins; Protein Precursors; Vasopressins

Topics: Accidents, Traffic; Adult; Brain Edema; Brain Injuries; Catecholamines; Fatal Outcome; Glasgow Coma Scale; Hematoma, Subdural; Humans; Hyperglycemia; Hyperkalemia; Hypokalemia; Hypothermia; Insulin; Intracranial Hypertension; Male; Mannitol; Norepinephrine; Potassium; Vasopressins