Biomaterial Database

Pulmonary shunt and cardiovascular responses to CPAP during nitroprusside-induced hypotension. 1977

M R Hodges, and T H Stanley, and R K Johansen

The effects of continuous positive airway pressure (CPAP) on cardiovascular dynamics and pulmonary shunt (QS/QT) were investigated in 12 dogs before and during sodium nitroprusside infusion that decreased mean arterial blood pressure 40-50 per cent. Before nitroprusside infusion, 5 cm H2O CPAP significantly, P less than .05, decreased arterial blood pressure, but did not significantly alter heart rate, cardiac output, systemic vascular resistance, or QS/QT. Ten cm H2O CPAP before nitroprusside infusion produced a further decrease in arterial blood pressure and significantly increased heart rate and decreased cardiac output and QS/QT. Nitroprusside caused significant decreases in arterial blood pressure and systemic vascular resistance and increases in heart rate, but did not change cardiac output or QS/QT. Five cm H2O CPAP during nitroprusside did not further alter any of the above-mentioned variables. However, 10 cm H2O CPAP decreased arterial blood pressure, cardiac output, and QS/QT. These data indicate that nitroprusside infusion rates that decrease mean arterial blood pressure by 40-50 per cent do not change cardiac output or QS/QT. During nitroprusside infusion low levels of CPAP do not markedly alter cardiovascular dynamics, but high levels of CPAP (10 cm H2O), while decreasing QS/QT, produce marked decreases in arterial blood pressure and cardiac output.

UI	MeSH Term	Description	Entries
D007023	Hypotension, Controlled	Procedure in which arterial blood pressure is intentionally reduced in order to control blood loss during surgery. This procedure is performed either pharmacologically or by pre-surgical removal of blood.	Controlled Hypotension,Hypotension, Induced,Induced Hypotension
D009599	Nitroprusside	A powerful vasodilator used in emergencies to lower blood pressure or to improve cardiac function. It is also an indicator for free sulfhydryl groups in proteins.	Nitroferricyanide,Sodium Nitroprusside,Cyanonitrosylferrate,Ketostix,Naniprus,Nipride,Nipruton,Nitriate,Nitropress,Nitroprussiat Fides,Nitroprusside, Disodium Salt,Nitroprusside, Disodium Salt, Dihydrate,Disodium Salt Nitroprusside,Nitroprusside, Sodium
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D011175	Positive-Pressure Respiration	A method of mechanical ventilation in which pressure is maintained to increase the volume of gas remaining in the lungs at the end of expiration, thus reducing the shunting of blood through the lungs and improving gas exchange.	Positive End-Expiratory Pressure,Positive-Pressure Ventilation,End-Expiratory Pressure, Positive,End-Expiratory Pressures, Positive,Positive End Expiratory Pressure,Positive End-Expiratory Pressures,Positive Pressure Respiration,Positive Pressure Ventilation,Positive-Pressure Respirations,Positive-Pressure Ventilations,Pressure, Positive End-Expiratory,Pressures, Positive End-Expiratory,Respiration, Positive-Pressure,Respirations, Positive-Pressure,Ventilation, Positive-Pressure,Ventilations, Positive-Pressure
D011652	Pulmonary Circulation	The circulation of the BLOOD through the LUNGS.	Pulmonary Blood Flow,Respiratory Circulation,Circulation, Pulmonary,Circulation, Respiratory,Blood Flow, Pulmonary,Flow, Pulmonary Blood,Pulmonary Blood Flows
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D002302	Cardiac Output	The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).	Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D005292	Ferricyanides	Inorganic salts of the hypothetical acid, H3Fe(CN)6.
D006339	Heart Rate	The number of times the HEART VENTRICLES contract per unit of time, usually per minute.	Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse