pituitrin and Respiratory-Insufficiency

Vasopressin is a peptide synthesized in the hypothalamus whose primary role is in fluid homeostasis. It has recently gained interest as a potential agent in the treatment of cardiorespiratory arrest. Initial human studies have shown benefits with vasopressin in patients with out of hospital ventricular fibrillation and asystolic cardiac arrest. One subgroup of patients not included in these trials is patients with pulmonary hypertension, who have a five-year mortality rate of 50%. Animal studies have shown vasopressin to be a vasodilator in the pulmonary vascular system of rats, under normoxic and hypoxic conditions, with conflicting results in canines. Human studies have shown conflicting results with increases, decreases and no changes seen in pulmonary artery pressures of patients with a variety of clinical conditions. Research needs to be done in patients with pulmonary hypertension regarding the potential role of vasopressin during cardiac arrest in this subgroup.

Topics: Animals; Dogs; Heart Arrest; Hemostatics; Humans; Hypertension, Pulmonary; Pulmonary Circulation; Rats; Respiratory Insufficiency; Swine; Treatment Outcome; Vasoconstrictor Agents; Vasopressins

Acute lung disease is commonly associated with interstitial pulmonary edema and a tendency towards partial or total alveolar collapse. To counteract this tendency mechanical ventilation is successfully used in most cases. Mechanical ventilation, however, leads to a harmful retention of water and salt, which may worsen interstitial pulmonary edema and further impair gas exchange. This problem seems to be less known. A survey of the effects of currently used modes of mechanical ventilation on excretory function and hemodynamics of the kidneys is given together with a short review of the possible afferent and efferent mechanisms which mediate the renal response to mechanical ventilation. Some clinical suggestions are made to break through the vicious cycle between mechanical ventilation and kidney function.

Topics: Animals; Dogs; Glomerular Filtration Rate; Humans; Kidney; Positive-Pressure Respiration; Renal Circulation; Respiration, Artificial; Respiratory Insufficiency; Vasopressins

Vasopressin is capable of being stimulated by several nonosmotic factors such as hypovolemia, hypotension, pharmacologic agents and stress. Vasopressin levels of only 1-2 pg/ml are capable of decreasing substantially renal water excretion. If water is ingested or given intravenously in this setting, positive water balance with hypotonicity and hyponatremia of extracellular fluid (ECF) occur. Such dilution of the ECF results in water movement into cells and potential central nervous system complications [3]. Many disorders (see Tab. 1) may be associated with nonosmotic stimulation of vasopressin release. In these clinical settings, judicious administration of free water and monitoring of serum sodium concentration is necessary. A knowledge of clinical conditions associated with vasopressin-mediated water retention may have therapeutic implications as well. Thus, in recent years it has become appreciated that selected pharmacologic agents such as lithium and demeclocycline can impair the water retaining property of vasopressin [26]. Although lithium appears too toxic for routine usage, demeclocycline has proved to be efficacious therapy in some patients with high vasopressin levels and hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone who are unable to limit their water intake [9]. More recently, other compounds that selectively antagonize the hydro-osmotic effect of vasopressin are being tested and soon may be available [13].

Topics: Adrenal Cortex Diseases; Blood Volume; Diuresis; Extracellular Space; Humans; Hyponatremia; Hypothyroidism; Inappropriate ADH Syndrome; Liver Cirrhosis; Osmosis; Respiratory Insufficiency; Vasopressins

Topics: Animals; Body Fluids; Cell Membrane Permeability; Chlorides; Dogs; Extracellular Space; Heart Failure; Humans; Hyponatremia; Infant Nutrition Disorders; Kidney; Liver Cirrhosis; Neoplasms; Osmolar Concentration; Potassium; Respiratory Insufficiency; Sodium; Vasopressins; Water; Whipple Disease

Topics: Acidosis, Lactic; Acute Disease; Administration, Intravenous; Adult; Aged; Alcoholism; Anti-Bacterial Agents; Bicarbonates; Comorbidity; Confusion; Glasgow Coma Scale; Humans; Hyperlactatemia; Hypotension; Intubation, Intratracheal; Male; Norepinephrine; Respiration, Artificial; Respiratory Insufficiency; Tachycardia; Thiamine; Vasoconstrictor Agents; Vasopressins; Vitamin B Complex

Status epilepticus causes significant morbidity and mortality. A case of generalized status epilepticus followed by massive pulmonary aspiration, acute respiratory failure and transient central diabetes insipidus is presented. Seizures were promptly controlled, but the patient required mechanical ventilation and correction of polyuria with desmopressin acetate. During hospitalization mental status improved, diabetes insipidus spontaneously remitted and he was discharged without neurologic sequelae. The clinical and pathophysiological features of this case are discussed.

Topics: Acute Disease; Adult; Diabetes Insipidus; Humans; Male; Pneumonia, Aspiration; Respiratory Insufficiency; Status Epilepticus; Vasopressins

A 65-year-old man who had muscle weakness and dysarthria was admitted for investigation of motor neuron disease. He had lost 12 kg of weight in 6 months. Neurological findings disclosed upper and lower motor neuron disturbances with normal sensory nerve function, and needle electromyography showed a neurogenic pattern. Laboratory findings on admission demonstrated dilutional hyponatraemia due to an excessive secretion of antidiuretic hormone (ADH). Based on these findings, the patient was diagnosed as having the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with amyotrophic lateral sclerosis (ALS). During the night of first hospital day, the patient complained of severe dyspnoea, and mechanical ventilation was commenced. Following the mechanical ventilation, plasma ADH levels and serum sodium concentration were normalized. We propose that respiratory failure secondary to the atrophy of respiratory muscle might be responsible for the development of SIADH.

Topics: Aged; Amyotrophic Lateral Sclerosis; Blood Gas Analysis; Diagnosis, Differential; Electromyography; Humans; Inappropriate ADH Syndrome; Male; Respiration, Artificial; Respiratory Insufficiency; Saline Solution, Hypertonic; Sodium; Vasopressins

We report 2 autopsy-proven cases of motor neuron disease/amyotrophic lateral sclerosis (MND/ALS), who developed the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) prior to the respiratory failure. With respect to the underlying mechanisms of SIADH in the cases, we considered two factors; 1) dysfunction of the feedback system in ADH secretion via intrathoracic volume receptors caused by changes in intrathoracic circulation, and 2) primarily functional abnormalities in the limbic system which could influence hypothalamic osmoreceptors. It appears that SIADH can be followed by an exacerbation of respiratory dysfunction in MND/ALS.

Topics: Amyotrophic Lateral Sclerosis; Feedback; Humans; Hypothalamus; Inappropriate ADH Syndrome; Limbic System; Male; Middle Aged; Motor Neuron Disease; Neurologic Examination; Respiratory Insufficiency; Vasopressins; Water-Electrolyte Balance

A 71-year-old female with amyotrophic lateral sclerosis (ALS) developed the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) during respiratory failure due to atrophy of the respiratory muscles. Serum sodium concentration fell to 116 mEq/l and then returned to the normal range after water restriction and respiratory care. This is considered to be the first case report of ALS associated with SIADH.

Topics: Aged; Amyotrophic Lateral Sclerosis; Blood Chemical Analysis; Electromyography; Female; Humans; Inappropriate ADH Syndrome; Respiratory Insufficiency; Sodium; Vasopressins

Plasma ADH, PA and PRA in patients with respiratory failure (RF) were studied. RF patients were divided into 4 groups, i.e. acute RF (ARF) and chronic RF (CRF), with or without hypercapnia. The levels of these hormones were significantly higher in RF than those in control subjects, moreover, they were markedly elevated in ARF than those in CRF. In multiple regression analysis, ADH correlated with PaO2, pH and PRA in RF patients, but correlated with serum osmolality in control subjects. It was considered that ADH in RF was affected by the direct effect of blood gases and circulatory disorder. The mechanism of elevated PA and PRA in RF probably was mediated through restriction of intake of water and Na, reduction of renal blood flow and decreased ACE often occurred in RF. Abnormally elevated hormones are more often recognized in edematous patients than in nonedematous patients. It was suggested that many patients with RF develop heart failure or edema due to hormonal abnormalities.

Topics: Acute Disease; Aged; Aldosterone; Chronic Disease; Female; Humans; Male; Middle Aged; Renin; Respiratory Insufficiency; Vasopressins

The major complication of extracorporeal membrane oxygenation (ECMO) for the treatment of neonatal respiratory failure is bleeding related to heparinization. Systolic hypertension has emerged as another serious side effect in our experience. Thirty-eight of the first 41 newborns we treated with ECMO developed a systolic blood pressure greater than 90 mm Hg. The mean hypertension index (HI blood = hours greater than 90/hr on ECMO) was 0.17 +/- 0.16. Possible biochemical mediators were assayed in 17 patients. Plasma renin activity (PRA), aldosterone, epinephrine, norepinephrine, prostaglandin E2, thromboxane, and antidiuretic hormone were elevated. Angiotensin-converting enzyme (ACE) and prostacyclin were not elevated. Eighteen patients (44%) had intracranial hemorrhage (ICH), and 11 patients (27%) had clinically significant ICH. The HI was significantly (p less than 0.005) lower in those patients without ICH (0.11 +/- 0.01) than in those patients with ICH (0.25 +/- 0.04). PRA at hour 12, day 2, and day 3 was significantly higher (p less than 0.05) in patients experiencing ICH (62 +/- 42; 93 +/- 15; 73 +/- 30 ng/ml/hr) than in those without ICH (27 +/- 25; 14 +/- 8; 12 +/- 4 ng/ml/hr). An aggressive approach to medical management evolved that included hydralazine, nitroglycerine, and captopril, which protected against ICH. Two of 23 patients (9%) treated with the protocol sufferred clinically significant ICH, whereas nine of 18 patients (50%) treated before implementation of the protocol experienced ICH. The ACE inhibitor captopril was most effective in the control of hypertension. We conclude that systolic hypertension is common during neonatal ECMO, is associated with ICH, and is related to a high PRA. Aggressive management of hypertension during ECMO can reduce the incidence of ICH, and captopril is an important component of this aggressive medical management.

Topics: Aldosterone; Cardiac Output; Catecholamines; Humans; Hypertension; Infant, Newborn; Oxygenators, Membrane; Peptidyl-Dipeptidase A; Prostaglandins; Renin; Respiratory Insufficiency; Thromboxane B2; Vasopressins

Topics: Adult; Aged; Aged, 80 and over; Body Water; Female; Humans; Kidney; Lung Diseases, Obstructive; Male; Middle Aged; Respiratory Insufficiency; Sodium; Vasopressins

The role of antidiuretic hormone (ADH) in the pathogenesis of renal impaired water excretion in acute respiratory failure has not been clearly delineated. Plasma sodium concentration and plasma ADH levels (radioimmunoassay) were therefore serially measured in 13 patients with acute respiratory failure (10 with acute exacerbations of chronic lung disease and three with acute lung disease) and eight "control" patients admitted ot the intensive care unit with suspected myocardial infarction. None of the patients had systemic hemodynamic, hepatic or renal dysfunction. ADH levels were significantly elevated in patients with acute respiratory failure (15.1 +/- 5.2 pg/ml versus 5.7 +/- 1.9 pg/ml, p less than 0.05) when compared with levels in control patients. The elevated ADH levels occurred despite significantly lower plasma sodium concentration (133 +/- 1 meq/liter versus 138 +/- 2 meq/liter, p less than 0.05) compared wit control values. Moreover, markedly increased ADH values (range 1.1 to 13.0 pg/ml) were often encountered in patients with acute respiratory failure despite significant hyposmolality (263 to 275 mOsm/kg H2O). This was not observed in any control patients. These results suggest that patients with acute respiratory failure are susceptible to water retention and hyposmolality due to nonosmotic release of antidiuretic hormone.

Topics: Acute Disease; Blood Gas Analysis; Body Water; Female; Humans; Kidney; Lung Diseases, Obstructive; Male; Osmolar Concentration; Prospective Studies; Respiratory Insufficiency; Sodium; Vasopressins

Topics: Acidosis, Respiratory; Animals; Blood Pressure; Diuresis; Dogs; Female; Hydrochloric Acid; Hydrogen-Ion Concentration; Hypercapnia; Hypophysectomy; Male; Norepinephrine; Osmolar Concentration; Respiratory Insufficiency; Vasopressins

Vasopressin has been used with increasing frequency to control gastrointestinal bleeding, the beneficial effect being attributed to marked splanchnic vasoconstriction. Because vasopressin may result in impaired cardiac function and because other potent vasoconstrictive substances have been shown to increase the pulmonary shunt and decrease arterial oxygenation, this study was undertaken to determind the effect of vasopressin on oxygen availability. Ten healthy anesthetized mechanically ventilated dogs received a five hour intravenous vasopressin infusion, 0.005 U/kg/min. The heart rate decreased moderately and briefly. The mean systemic arterial pressure increased and then decreased, both minimally. The pulmonary shunt and the arterial oxygen content decreased slightly. The total systemic resistance increased and the stroke volume decreased, both substantially. The pulmonary artery wedge pressure gradually increased. The oxygen availability decreased markedly. This study demonstrated that a vasopressin infusion causes a marked decrease in oxygen availability due primarily to a decreased stroke volume and, to a lesser extent during the first hour, to a decreased heart rate. The pulmonary shunt did not increase. Increased systemic resistance followed by a gradual increase in the pulmonary wedge pressure suggests that the decreased stroke volume resulted, at least in part, from an increased afterload and left ventricular failure. It is suggested that until the effect of vasopressin on the cardiopulmonary systems and hence oxygen availability is fully studied in critically ill patients, that it be used with caution and with appropriate hemodynamic monitoring.

Topics: Animals; Blood Pressure; Cardiac Output; Dogs; Heart Rate; Hemodynamics; Infusions, Parenteral; Oxygen; Pulmonary Circulation; Respiratory Insufficiency; Stroke Volume; Vascular Resistance; Vasopressins

Diabetes insipidus following cardiac arrest and hypoxemic encephalopathy occurred in two patients. In both, severe hypoxemic brain damage was followed within three days by clinical and laboratory features of diabetes insipidus, which were corrected by administration of exogenous vasopressin. Hypothalamic injury resulting in diabetes insipidus should be considered in the differential diagnosis of polyuria and dehydration occurring in critically ill patients who have suffered cardiorespiratory arrest.

Topics: Adult; Diabetes Insipidus; Female; Heart Arrest; Humans; Hypothalamus; Hypoxia; Hypoxia, Brain; Respiratory Insufficiency; Vasopressins

Topics: Aged; Chronic Disease; Humans; Lung Diseases, Obstructive; Male; Respiratory Insufficiency; Respiratory Tract Infections; Vasopressins

Topics: Adolescent; Aged; Blood Pressure; Carbon Dioxide; Cardiac Output; Central Venous Pressure; Female; Humans; Kidney; Lung Compliance; Male; Middle Aged; Osmolar Concentration; Oxygen; Positive-Pressure Respiration; Potassium; Pressure; Respiration, Artificial; Respiratory Insufficiency; Sodium; Urine; Vasopressins; Water

Topics: Acid-Base Equilibrium; Acidosis, Respiratory; Chlorides; Diuretics; Electrolytes; Glucose; Humans; Hyperkalemia; Hypokalemia; Hyponatremia; Respiratory Insufficiency; Respiratory Tract Diseases; Vasopressins; Water-Electrolyte Balance

Topics: Adolescent; Adult; Aged; Body Weight; Child; Diuretics; Edema; Female; Heart Failure; Hematocrit; Humans; Lung; Lung Compliance; Male; Middle Aged; Oxygen; Positive-Pressure Respiration; Pulmonary Edema; Radiography; Respiration, Artificial; Respiratory Function Tests; Respiratory Insufficiency; Sodium; Vasopressins; Water-Electrolyte Balance

Topics: Humans; Lung Neoplasms; Male; Metabolic Diseases; Middle Aged; Respiratory Insufficiency; Vasopressins