The Care Management of an Adult Patient with Central Venous Line - Essay Example

Name: Instructor: Course: University: Date Submitted: The care management of an adult patient with central venous line 1. Introduction Management of Central venous pressure is essential in treating the patients with septic shock. Doctors find the need of maintaining CVP while adjusting cardiac preload, contractility, after-load to balance systemic oxygen delivery on demand. Maintenance of adequate central venous pressure helps in carrying out hemodynamic adjustments and maximizing mixed or central venous oxygen saturation. In general patient need CVP greater than 8mm Hg in case of one lactate greater than 4mmol/L and initial fluid challenge with 20mL/Kg of crystalloid equivalent. Management of CVP includes maintaining CVP, considering blood products, maintaining pressure in mechanically ventilated patients, in the cases to increase abdominal pressure and in the cases of septic patients having multi-factorial aspects that demand CVP. 1 2. Literature Review 2.1 General View about CVP: CVP is a direct measurement of the blood pressure in the right atrium and vena cava. The system acquires this pressure threading a central venous catheter into any of various large veins in the cavity. A pressure monitoring assembly in distal port of a multilumen central vein catheter helps in monitor the CVP. The CVP catheter is a significant tool to assess the right ventricular function and systemic fluid status. In normal conditions, the CVP is 2-6mm Hg. CVP increases due to over-hydration that increases venous return. The heart failure or PA stenosis also may lead to venous congestion as it limits the venous outflow. CVP decreases below normal due to hypo-volemic shock from haemorrhage. This may be due to fluid shift and dehydration. The mechanical negative pressure used for high spinal cord injuries also can lead to the decrease of CVP. Considering above-mentioned measurements, the CVP catheter is an important tool for treatment. The monitoring is essential in the cases of rapid infusion, infusion of hypertonic solutions and medications that may damage veins and venous blood assessment. 2 2.2 Definition and Measurement: According to publications of Sepsis Surviving Campaign, there are no definite calculations provided for Central Venous Pressure. Clinicians like to have a not that central venous pressure as an estimate of volume status that is underestimated in patients receiving positive end expiratory pressure. This is due to absence of measurement tool to account for the effects of PEEP on CVP. 3 2.3During Liver Transplantations: The effect of low central venous pressure is a factor in transfusion requirements of blood products during liver transplantations and has considerable effect. According to Massicotte et al observation in 2006 regarding liver transplantations, maintaining low central venous pressure through restriction of volume replacement corrected the coagulation defects with plasma transfusion. The basis is regarding the observation of the results in 100 liver transplantations during a two-year period. They concluded that the avoidance of plasma transfusion and maintenance of low CVP before anhepatic phase finds its association with RBC transfusions during liver transplantations. This study supports practicing of lowering CVP with phlebotomy in order to reduce blood loss during liver dissection without harmful effect. 4 2.4 Relationship with Arterial Blood Pressure: The Arterial Blood Pressure is dependent on the product of cardiac output and peripheral resistance. Heart rate and stroke volume control cardiac output. The stroke volume is in turn, related with myocardial contractility and blood volume. The central venous filling or central venous pressure depends on the above-mentioned conditions. Due to this, the venous pressure originates from the arterial pressure. This is in turn, transmitted through the capillary pressure into the venous reservoir. The effects of three factors that include circulation then calculate the CVP. Those three effects are Cardiac pump action, Circulating blood volume and vascular tone. Cardiac pump action contains inflow that accelerates venous flow and outflow that impedes the venous pressure. The circulating blood volume is a determining factor in the maintenance of central venous pressure. This is because the venous side of vascular system accommodates 50 to 55 percent of total blood volume. Vascular tone refers to external pressure exerted on veins. This depends on contractility of veins, as the veins are resistance vessels. The stimulation of alpha-receptor sites can result in vasoconstriction. Other factors that contribute to external and lateral pressure are pressure by skeletal muscles, tone and pump valve effects. The tissue pressure and respiratory movements also result in exerting CVP. However, the CVP is not an index of blood volume per second as it is the analysis of the interrelated effects of the blood volume, cardiac pump action and vascular tone. 5 The above facts are utilised in anaesthesia practices in kidney recipients to monitor and manage central venous pressure. According to the study (N. Hadimioglu, 2006) on 30 consecutive kidney recipients who had no valvular disease or clinically left ventricular failure, there is a highly significant relation ship between peripheral venous pressure and central venous pressure with a Pearson correlation coefficient of 0.97. The study concluded that the PVP is consistently in high agreement with CVP in the peri-operative period among the patients with no cardiac dysfunction. The researchers in this study observed that the PVP is 13.5 Hg and CVP is 11.0 Hg during surgery with a variance of 1.8 to 1.5 Hg respectively. The repeated measurements also indicated the highly significant relationship between PVP and CVP. 6 The facts and findings mentioned in this chapter are useful in analysing the practical purposes of CVP in critically ill patients. 3. Significance of CVP 3.1 Non-Invasive Measurement: According to Christoph Thalhammer and colleagues of University Hospital Basel, central venous pressure is important in monitoring heamodynamics in seriously ill patients. This is a method does not need central venous access using sonography at forearm. Clinical observations reveal that the sonography techniques involve the visualising a cephalic vein and measuring the pressure need to compress the vein. According to the study on 10 healthy adult volunteers, there is a strong correlation between non-invasive and invasive measurement during induced degrees of hypertension. When the same research is done on 50 intensive care patients, it has been found that there exists a mean difference between CVP measured invasively and noninvasively, which is negligible. This is negligible below and at the heart level. Though the study excluded some critically ill patients due to venous punctures, they concluded that the method is not suitable for continuous monitoring. However, this is an attractive alternative for assessment of emergency room patients when invasive technique is less then the best. 7 3.2 Use of CVP Catheters in ICU and adult patients: In adult patients, the vascular access helps in using CVP catheters in ICU. The adult patients in ICU are in general edematous and peripheral vascular access may be difficult. In this condition, the large-bore central venous catheter is useful for volume resuscitation of patients in shock. If the patients receive inotropes and vasopressors, may result in tissue necrosis. Here central venous catheter provides a standard of care for those patients to deliver antibiotics and potassium chloride in lower doses, thus controlling central venous pressure. Adult patients with mechanical ventilation, pulmonary hypertension and severe ventricular dysfunction, the patients need measurement of central venous pressure due to cannulation. In general, it reflects the right ventricular preload. If the patients are severely ill, clinical practices involve adequate volume resuscitation to control sepsis syndrome. In these cases, the CVP may not clearly reflect the preload and needs caution in interpreting. Placing of pulmonary artery catheter helps in accurate assessment. To avoid central venous catheter infection, the use of antimicrobial-impregnated catheters recommended. 8 3.2 Usage of Peripheral Pressure instead of central venous pressure: In adult patients the tricuspid valve, superior vena cava and hepatic vein Doppler patterns is in general abnormal finds application in the case of predicting high central venous pressure. Only Hepatic vein peak D correlated with CVP and there is no near correlation between other factors and CVP. 9 3.3 Prevention of Air Embolism in Adult patients in Neck and Head Surgeries: In case of adult patients with neck and head surgeries, a central venous pressure multichannel catheter insertion is via sub-clavian or a jugular vein just into the superior cava vein. This enables to measure the pressure difference between proximal distal ports. By inflating the balloon, the blood pressure at the site of surgery relative to the environment can be brought to near zero. In case of adult patients, the catheter diameter is about 3mm in diameter to cause minimum blockage. In this context, the diameter of the balloon will be more than 1.5 cm. In general, the clinical practice is to insert the catheter 10 (used in adults) in the neck veins when the patient is about supine and head down. There is no threat of introducing air in the afore-mentioned condition. The practice is to record the CVP at lumens 14 and 16 after the patient returns to horizontal position. When the Anaesthesia begins, the position of patient is to sit up to the required level. The recording of new pressure readings is necessary at this. The changes in pressure between catheter ports 22 and 24 indicate changes in cardiac output and require continuous monitoring. If there is any need of increasing and decreasing of pressure, they manage accordingly by readjusting the balloon pressure and size to maintain the optimum pressure difference. The anaesthesia levels can stabilise the cardiac output and for that, the difference in ports pressure indicate balloon size adjustments. 10 4. Care During Various Clinical Practices In a number of clinical practices, the monitoring of central venous pressure is important. This is because; in cases like living-donor, liver transplantation the blood loss is associated with morbidity and mortality. The clinical practice is to maintain lower central venous pressure to reduce blood loss during resection. This needs monitoring and management of central venous pressure in living-donor hepatectomies. This rationale is supported by evidence by investigations of Niemann and his colleagues during intra-opertive management of central venous pressure in living-donor hepatectomies. 11 In a study of Abduiaziz Alzccr in 1998 found that, the investigation on the effect of central venous pressure on common iliac vein reflect on right atrial pressure in adult patients. This study evaluated the pressure readings of right atrium in 26 mechanically ventilated adult patients. A correlation between TCVP and ACVP indicated the avoidance of complications by adopting femoral route for measurement of central venous pressure. The femoral vein veni-puncture is safe when compared to the effects like pneumothorax, haemothorax, air embolism, arterial puncture, bleeding, dysrhythmias and thoracic duct injury associated with internal jugular or sub-clavian veins. However, it is not free from complications like local haematoma, femoral lartery laceration and occasional femoral nerve damage. 12 In some cases, the resuscitation in Sepsis of a patient in ICU needs measurement of CVP as a measure of recovery. The improvised supportive care resulted in eradication of infectious focus and fluid resuscitation. This treatment should begin as early as the condition is recognized and resuscitation targets are measured according to central venous pressure of 8 to 12 mm Hg, and a mean arterial pressure of at least 65 mm Hg. 13 Adult patients with meningococcal septicaemia display different degrees of symptoms and may result in multiple organ failure. Within the first hour of the ICU care, the patient may become increasingly tired and drowsy and fluid resuscitation will be in process. Nurse need to monitor continuously, the arterial and central venous pressures. These need the recording of blood pressure and central venous pressure. These observations enable accurate manipulation of fluids and inotropes to maximize organ perfusion. Arterial blood gases are taken at hourly intervals along with central venous pressure. 14 In cases of adult patients with congenital diaphragmatic problems, eventrtion is an uncommon condition that is a result of abnormal elevation of diaphragm. During the surgery, the intra-abdominal pressure and anaesthetic management play an important role that involves the monitoring and management of central venous pressure. In case of such patients, the premedication with oral 10 mg diazepam is necessary before the surgery. The routine monitoring is about non-invasive blood pressure and pulse oximetry. In this type of case, the trachea is in-tubated and mechanical ventilation with pressure-controlled mode is necessary. By arranging a total fresh gas flow of 2 L /min, an arterial catheter in radial artery is necessary for continuous blood pressure that monitors central venous pressure. The central catheter placed percutaneously through left brachial vein helps in measuring CVP. This is necessary for increasing and decreasing of CVP according to necessity. CVP maintenance at 7 to 10 cm H2O is necessary through out the operation. In general, the above-mentioned conditions ensure the oxy-haemoglobin saturation of 96% when breathing room air after the surgery. 15 Works Cited 1. Surviving Sepsis Campaign, Maintain Adequate Central Venous Pressure, Surviving Sepsis Campaign, 2008, Accessed on 12th April 2008 from 2. Surviving Sepsis Campaign, Maintain Adequate Central Venous Pressure, Surviving Sepsis Campaign, 2008, Accessed on 12th April 2008 from < http://www.survivingsepsis.org/how_to_improve/measures_CVPgoal> 3. Massicotte L et al, Effect of low central venous pressure and phlebotomy on blood product transfusion requirements during liver transplantations, noblood.org, Accessed on 12th April 2008 from 4. Rnceus, Central Venous Pressure Monitoring, rnceus.com, Accessed on 13th April 2008 from 5. Leonabd C. Jenkins et al, Central Venous Pressure Monitoring in Anaesthesia, Canadian Anaesthetists' Society Annual Meeting, Accessed on 14th April 2008 from http://www.cja-jca.org/cgi/reprint/13/5/513.pdf 6. N. Hadimioglu et al, Correlation of Peripheral Venous Pressure and Central Venous Pressure in Kidney Recipients, Science Direct, Accessed on 14th April 2008 from 7. J Am Coll Cardiol, Central Venous Pressure Can be Measured Noninvasively by Sonography, Reuters Health Information, Accessed on 14th April, 2008 from 8. Michael A. Gropper, Ask the Experts on Central Venous Pressure Catheters, medscape.com, Accessed on 14th April 2008 from http://www.medscape.com/viewarticle/439833 9. SASKIA RITTER, Can Doppler Systemic Venous Flow Indices Predict Central Venous Pressure in Children?, Blackwell Synergy, Accessed on 15th April 2008 from http://www.blackwell-synergy.com/doi/abs/10.1111/j.1540-8175.2000.tb01113.x?cookieSet=1&journalCode=echo 10. Aillon, Rene , Central venous pressure catheter for preventing air embolism and method of making , Free Patents Online, Accessed on 16th April 2008 from 11. Niemann, Central venous monitoring is not required during living-donor hepatectomies, Nature Clinical Practice Gastroenterology and hepatology, Accessed on 16th April 2008from http://www.nature.com/ncpgasthep/journal/v4/n5/full/ncpgasthep0777.html 12. Abduiaziz Azeer, Central Venous Pressure From Common Iliac Vein reflects Right Atrial Pressure, cja-jca.org, Accessed on 16th April from http://www.cja-jca.org/cgi/reprint/45/8/798.pdf 13. Gregory S. Martin, The Surviving Sepsis Campaign: Clinical Practice Guideline Revisions for Improving Outcomes in Sepsis, medscape.com, Accessed on 16th April 2008 from 14. Inmed, Adult Meningococcal Septicaemia, inmed.co.uk, Assessed on 16th April 2008 from 15. Hale YARKAN UYSAL et al, Anaesthesia for an Adult Patient with Congenital Diaphragmatic Eventration, journals.tubitak.gov.tr, Assessed on 16th April 2008 from journals.tubitak.gov.tr/medical/issues/sag-07-37-5/sag-37-5-10-0706-10.pdf Read More