PRESENTATION ON “ RESPIRATORY SYSTEM” “ AHMAD ALI SHAH”
INTRODUCTION Blood from systemic veins flows into the right atrium; the pressure in the right atrium is the central venous pressure (CVP). CVP is determined by the function of the right heart and the pressure of venous blood in the vena cava. Under normal circumstances an increased venous return results in an augmented cardiac output, without significant changes in venous pressure. However with poor right ventricular function, or an obstructed pulmonary circulation, the right atrial pressure rises. Loss of blood volume or widespread vasodilation will result in reduced venous return and a fall in right atrial pressure and CVP.
AIM To share the knowledge among the participants about central venous pressure.
OBJECTIVES At the end of this presentation the participant will be able to: Define the central venous pressure. In list parts of respiratory system Discuss on respiratory process Explore external and internal respiration know about the lungs volume Regulation of respiration by the nervous system
DEFINITION Central venous pressure (CVP) describes the pressure of blood in the thoracic vena cava, near the right atrium of the heart.cvp reflects the amount of blood returning to the heart and the ability of the heart to pump blood into the arterial system.
Factors affecting CVP Factors that increase CVP include: Hypervolemia forced exhalation Tension pneumothorax Heart failure Pleural effusion Decreased cardiac output Cardiac tamponade Mechanical ventilation and the application of positive end-expiratory pressure (PEEP)
Cont…. Factors that decrease CVP include: Hypovolemia Deep inhalation Distributive shock .
TYPES OF CVP LINE
Central Line Complications Infections Air embolus Dislodgement of catheter Catheter occlusion
INSERTION SITES FOR CVP LINE Right internal jugular left internal jugular right subclavian left subclavian femoral
Indications for CVP lines are fluid resuscitation Parenteral feeding measurement of central venous pressure poor venous access administration of irritant drugs
COMPLICATIONS FOLLOWING CVP LINE INSERTION Malposition of the catheter haematoma arterial puncture pneumothorax haemorrhage sepsis air emboli Catheter embolism Thrombosis Haemothorax Cardiac tamponade Cardiac arrhythmias
NURSING CARE Monitor the patient for signs of complications Label CVP lines with drugs/fluids etc. being infused in order to minimise the risk of accidental bolus injection If not in use, flush the cannula regularly to help prevent thrombosis. A 500ml bag of 0.9% normal saline should be maintained at a pressure of 300mmHg.
CONT… Ensure all connections are secure to prevent exsanguination, introduction of infection and air emboli Observe the insertion site frequently for signs of infection. The length of the indwelling catheter should be recorded and regularly monitored. CVP lines should be removed when clinically indicated
REFERENCES H enderson N., (1997) Central Venous Lines Nursing Standard 11:42, pp49-56 Mallett J., (2000) The Royal Marsden NHS Trust Dougherty L., Manual of Clinical Nursing Procedures, Fifth Edition Oxford; Blackwell Science, pp630-635. Mc Dermott M., (1995) Central Venous Pressure Nursing Standard 9:35, pp54 Nursing Standard., (1999) Quick Reference Guide 6. Central Venous Lines Nursing Standard 13:42.