Central venous pressure

Vasodilators are a group of dtugs, which relax the smooth muscle cells of the blood vessels and lead to an increased local tissue blood flow, a reduced arterial pressure and a reduced central venous pressure. Vasodilators reduce the cardiac pre-load as well as after-load and thereby reduce cardiac work. They are used in a variety of conditions including hypertension, cardiac failure and treatment/prevention of angina pectoris. Major groups are Ca2+-channel blockers (e.g. dihydropyridines), NO-donators (e.g. organic nitrates), K+-channel openers (minoxidil), phosphodiesterase inhibitors (e.g. sildenafil), Rho-kinase inhibitors (e.g. Y27632) or substances with unknown mechanism of action (e.g. hydralazine). Inhibitors of the... 

Monitoring the patient in shock requires vigilance on the part of the nurse The patient s heart rate, blood pressure, and ECG are monitored continuously. The urinary output is measured often (usually hourly), and an accurate intake and output is taken. Monitoring of central venous pressure via a central venous catheter will provide an estimation of the patient s fluid status. Sometimes additional hemodynamic monitoring is necessary with a pulmonary artery catheter. The use of a pulmonary artery catheter allows the nurse to monitor a number of parameters, such as cardiac output and peripheral vascular resistance The nurse adjusts therapy according to the primary health care provider s instructions. 

Titrate to appropriate volume status and central venous pressure... 

FIGURE 10-4. Treatment algorithm for the management of moderate to severe hypovolemia. BP, blood pressure CVP, central venous pressure ECG, electrocardiogram MAP, mean arterial pressure PA, pulmonary artery PAOP, pulmonary artery occlusion pressure PRBCs, packed red blood cells SBP, systolic blood pressure. 

The clinical scenario and the severity of the volume abnormality dictate monitoring parameters during fluid replacement therapy. These may include a subjective sense of thirst, mental status, skin turgor, orthostatic vital signs, pulse rate, weight changes, blood chemistries, fluid input and output, central venous pressure, pulmonary capillary wedge pressure, and cardiac output. Fluid replacement requires particular caution in patient populations at risk of fluid overload, such as those with renal failure, cardiac failure, hepatic failure, or the elderly. Other complications of IV fluid therapy include infiltration, infection, phlebitis, thrombophlebitis, and extravasation. 

A pulmonary artery (Swan-Ganz) catheter can be used to determine central venous pressure (CVP) pulmonary artery pressure CO and pulmonary artery occlusive pressure (PAOP), an approximate measure of the left ventricular end-diastolic volume and a major determinant of left ventricular preload. 

Immediate initial resuscitation of a patient in severe sepsis or sepsis-induced tissue B hypoperfusion should be instituted to achieve central venous pressure 8-12 mm Hg mean arterial pressure >65 mm Hg urine output >0.5 mt/kj hour, central venous or mixed venous oxygen saturation >70%... 

Central venous pressure (CVP) The usual CVP trace should be drawn on at a pressure of 5-10 mmHg. The c wave occurs during IVC owing to bulging of the closed tricuspid as the ventricle begins to contract. The y descent occurs immediately following IVR as the tricuspid valve opens and allows free flow of blood into the near empty ventricle. 

The central venous pressure is the hydrostatic pressure generated by the blood in the great veins. It can be used as a surrogate of right atrial pressure (mmHg). 

Shock IV Infusion Rate of 0.5-5 mq min (0.25-2.5 ml of 1 500,000 dilution) rate of infusion based on clinical response (heart rate, central venous pressure, systemic BP, urine flow measurements). 

Less effective compared to morphine, but less respiratory depression and opposite cardiovascular pharmacodynamics increases pulmonary, arterial, and central venous pressure... 

GTN is a nitrate. This class of drugs are potent vasodilators. At therapeutic doses the main effect of nitrates is to act on vascular smooth muscle to dilate the veins, thus reducing central venous pressure (preload) and ventricular end-diastolic volume. The overall effect is to lower myocardial contraction, wall stress and oxygen demand, thereby relieving the angina. Nitrates also promote vasodilation of the coronary blood vessels. 

She had good cardiac output with a raised heart rate (109) and central venous pressure of 18 mmHg with bilateral wheeze and fluid overload. The family were told she had a 50-50 chance of survival. 

The next day the patient had decreased respiratory rate, became tired with falling blood sugar and acidosis. She had acute renal failure with urine output <30 mL/h and was in fluid overload. The doctors started her on terlipressin 2 mg q.d.s. and HAS (Human Albumin Solution) 20% to maintain central venous pressure 8-12 mmHg and prevent hepatorenal syndrome. Terlipressin is a prodrug for vasopressin. 

A pulmonary artery (Swan-Ganz) catheter can be used to determine central venous pressure (CVP) pulmouary artery pressure CO aud pulmonary artery occlusive pressure (PAOP), an approximate measure of the left ventricular eud-diastolic volume aud a major determinaut of left veutricular preload. CO (2.5 to 3 L/min) and mixed venous oxygeu saturatiou (70% to 75%) may be very low in a patient with extensive myocardial damage. Respiratory alkalosis is associated with low partial pressure of O2 (25 to 35 mm Hg) and alkaline pH, but uormal bicarbouate. The first two values are measured by arterial blood gas, which also yields partial pressure of carbon dioxide and arterial oxygen saturation. Circulating arterial oxygen saturation can also be measured by an oximeter, which is a noninvasive method that is fairly accurate and useful at the patient s bedside. 

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