Overview of Hemodialysis

Hemodialysis is done to patients in hospitals or health centers. Furthermore, it is done on patients with kidney failure on the advanced stage. An artificial kidney performs hemodialysis; it has a dialyzer that filters extra fluid and wastes from the blood. Patients who present at the renal unit are trained to be very independent (Mayo Clinic, 2018).

The weight of each patient is taken so that the nurses can know the exact amount of fluid each patient needs to remove. Some patients can connect themselves to dialysis machines depending on their vascular access. Nurses entirely check them and regularly monitor their blood pressure. Furthermore, they need excellent communication skills to communicate with patients and make them comfortable effectively. The essay discusses a day in the dialysis unit, the various components of a dialysis machine and how they function. Furthermore it discusses patient education in dialysis.

Hemodialysis is a process that uses an artificial kidney to remove metabolic wastes, urea, excess fluid, and toxins from the blood. Dialysis is the movement of water and solutes across a semi-permeable membrane along a concentration gradient. Hemodialysis is the exchange of solutes and water between an artificial solution known as dialysate and blood in the body across a semipermeable membrane (Mackenzie & Zawada, 2005).

The fluid exchange removes toxins and metabolic wastes in the blood. Furthermore, it corrects the electrolytes, fluid, and acid-base arrangements. Small molecular weight solutes, water, and uremia toxins pass through membrane pores along hydrostatic and diffusive gradients. However, the movement of plasma proteins, large solutes, and blood cellular components are limited to pore sizes. Excess water and other solutes are forcibly removed through the membrane by ultrafiltration, which is produced by osmotic and hydrostatic forces in the dialysis membrane. The removal of uremic solutes is influenced by the concentration gradient, permeability characteristics of the membrane, blood flow, duration of dialysis and the amount of ultrafiltration (Blowey, 2005).

  Pre-dialysis involves intensive patient education, adherence to lifestyle modifications and pharmacotherapy. The symptoms of uremia are handled by a nephrologist who analyses urine tests and blood tests. Each patient is diagnosed and treated for the risk factors to reduce mortality and comorbidity. Furthermore, the nephrologist discusses adherence to prescribed medicines, daily exercise, healthy diet, quit habits such as smoking. Pre-assessment supports patients in coping up with the real stress that accompanies dialysis so that they can identify renewed balance in life (Yvo, Noeleen & Ton, 2008).

Components of a Dialysis Machine

  The patients experience many symptoms which are not easily recognized or treated. Furthermore, they experience post-dialysis fatigue after dialysis sessions. The dry weight is encountered at the end of the dialysis process, which leaves the patient with symptoms of hypotension and low weight. The overestimation of dry weight can lead to potential hazards of overhydration such as pulmonary edema and hypertension. Underestimation can make dialysis patients suffer hypotensive episodes (Watson, 2008).

  The arteriovenous fistula is formed by linking the patient’s vein and artery in the limb. It is done using a local anesthetic as an outpatient operation. The vein grows stronger as blood flows from the newly connected artery to the vein. Furthermore, a patient is shown how to do workouts such as pressing a rubber ball on the hand to help the fistula toughen up.This procedure can take approximately five to six weeks (Davita Kidney Care, 2018).

The fistula matures after the period. Therefore, it can provide a good flow of blood during hemodialysis. Kidney experts such as the National Kidney Foundation, consider AV as a gold standard choice of access in hemodialysis. People with fistula have few complications when compared to other regions of access (Davita Kidney Care, 2018).

Fluid overload also known as hypervolemia is having too much fluid in the body. Signs of hypervolemia include swelling in the ankles, feet, face, and wrists. Furthermore, symptoms include body discomfort, stomach bloating and headache (Carissa, 2017).

 Kidney failure causes hypervolemia. Typically, kidneys balance the number of fluids and salts in the body. However, when kidneys retain salts, the fluid content increases.  Heart failure especially the left ventricle, liver cirrhosis, kidney failure due to diabetes, premenstrual edema that occurs before menstruation in women and hormonal imbalance caused by pregnancy because of fluid overload (Carissa, 2017).

Hypervolemia is diagnosed by observing the weight gain and swelling in body parts.  A blood test is conducted to asses sodium levels. High sodium levels are an indication of hypervolemia. Urinary sodium content is usually higher than 20 milliequivalents per liter (mEq/L). In the case of heart failure, nephrotic syndrome and cirrhosis sodium content are less than ten mEq/L (Carissa, 2017).

The dry weight is the average weight of the body without any other fluid; extra fluid causes extra strain in the body. Dialysis gets rid of excess wastes and fluids that build up in the body in between treatments. The symptoms of dizziness, cramping or nausea are experienced due to the removal of too much fluid; too much extra fluid in the body requires longer hemodialysis treatments (Jack & Ravindra, 2000).

Patient Education in Dialysis

A kilogram is the standard measure of dry weight; it is equivalent to 2.2 pounds. Many hemodialysis patients need to reduce the weight gained in each session to less than 2.2 pounds between dialysis sessions (National Kidney Foundation, 2018).

Potassium is checked before dialysis to regulate its levels during dialysis sessions. If the levels of potassium are high, breathing problems are experienced, and this affects the regular heartbeat. A dietician can help avoid high potassium foods if the levels are high before dialysis. Low potassium levels require more dialysis fluid to boost the levels (Queen Elizabeth Hospital, 2017).

Bicarbonate acid reduces with kidney failure; if the level is too low, then more bicarbonate is needed in the dialysis fluid. Levels of urea checked in blood URR, and eKt/V values indicate the dose of dialysis you have had in a particular day. The two values are calculated from urea levels in the blood. Urea is a toxin removed from the body by the kidneys. By calculating the levels of urea, the efficiency of the dialysis process in cleaning the blood can be assessed. Toxins can build in the body if the levels are high before dialysis. The dialysis line is not working correctly, or the dialysis prescription needs to be changed if the URR or eKt/V is low. Therefore, the flow of blood should be increased (Queen Elizabeth Hospital, 2017).

The most common difficulty that accompanies dialysis especially for people with diabetes is hypotension. Hypotension leads to muscle cramps, nausea, or abdominal cramps. Furthermore, muscle cramps are common during hemodialysis. The pain is reduced by adjusting the prescription. Moreover, the patients have sleeping issues because breathing breaks during sleep (Mayo Clinic, 2018).

Furthermore, anemia is a common complication of dialysis. Kidneys that have failed cannot produce the erythropoietin hormone, which is involved in the formation of red blood cells. Removal of vitamins and irons due to hemodialysis can also contribute to anemia (Mayo Clinic, 2018).

 Also, too much fluid between hemodialysis treatments can lead to heart failures. Also, hemodialysis contributes to high levels of potassium ions.  The kidneys are involved in the removal of potassium ions from the body. Therefore, in the case of kidney failure, the potassium levels in the body increases hence the heart can stop (Paweena, & Bertrand, 2017).

The Gambro AK 96 machine set up

The Gambro AK 96 machine has innovative features such as the Discan system and a new user interface that provides consistent and reliable HD treatments. Furthermore, it has a standby mode that allows users to be flexible in preparation of fluid and save both the concentrate and water. The Discan system enables Kr/V measurements and clearance surveillance. The system allows for consistency and improved control in treatment delivery. The system provides issuance of prescription to patients (Gambro, 2018).

Pre-dialysis Preparations

The chain prevents bacterial growth and biofilm. Furthermore, it stops endotoxins from getting to patients. Therefore, it reduces the occurrence of microbiological side effects, treatment-related inflammatory episodes, and exposure to toxic disinfectant. It promotes a better patient outcome (Gambro, 2018).

The chain has full control of the machine. Furthermore, it has traceability through the recorded history of disinfection, maintenance programmability, full integration with water treatment, 93⁰ heat disinfection, a drainable single pass fluid and a UFD kit used to produce an ultrapure dialysis fluid. This set up reduces contamination by endotoxins levels in the fluid; it has diminished micro-inflammation and improved response to erythropoietin therapy (Gambro 2018).

Low access pressure alarm has a pressure gauge that measure the negative pressure made by the access pump that sucks blood from the patient and pushes it into a filter. The maximum pressure tolerated is -250mmHg, an increase will lead to a” low access “pressure alarm. The patient should have enough venous blood or the vascath should be checked for kink (Gambro, 2018).

  The high return pressure alarm is triggered when the maximum tolerated pressure goes above 300mmHg.The pressure gauge measures the positive pressure created by a return pump , which sucks blood from the filter into the patient. To, manage it; the vascath kink should not be dislodged (Gambro, 2018).

Furthermore, when the filter is dying, the high filter pressure alarm is triggered. It goes off when the difference between return pressure and filter pressure is higher than 250 mmHg. The line moving to the filter should be free from kinks. Finally, the low return pressure alarm is triggered by the return pump pressure gauge due to negative pressure, no clamp is anywhere in order to manage it (Gambro, 2018).

The AK 96 machine has separate hardware for protection and control systems. It has a separate AD converter, CPU board, and connecting wires. This unique design allows each system to operate independently for higher safety. The AK 96 machine assists with automation during priming, rinse back or patient connection. The direct access to alarm conditions and the convenient alarm layout reduces stress in treatment (Gambro, 2018).

Conductivity in the dialysate fluid is composed of electrolyte concentrations, and positively charged ions such as potassium, calcium, sodium and magnesium. It is maintained between 12 to 16 m S/cm. The monitor of conductivity is always in contact with the dialysate and it has two electrodes across which a constant voltage is applied. Therefore, changes in the concentration of electrolyte would cause changes in voltage (Gambro, 2018).

Potential Complications of Hemodialysis

Venous Pressure Monitor monitors pressure in the venous drip chamber. This is a segment that exists between the patients venous access and the drip chamber, and an extra intra access pressure. A resistance to blood entering the venous access would lead to a positive pressure above 0 mmHg (Gambro, 2018).

The pre blood pump immediately delivers replacement fluid to the blood circuit after it is pulled into the circuit at site of access. Furthermore, it effectively delivers anticoagulants in the blood circuit. It is also a form of hemofiltration that involves removal of large amounts of plasma in dialysis (Gambro, 2018).

The Trans membrane Pressure (TMP) monitor’s the function of the filters. It rises as the filter gets clogged with filth. However, if it rises suddenly then the filtrate line has become clamped or kinked (Gambro, 2018).

The Water System in Hemodialysis Machines.

The success of hemodialysis depends on the availability of ultra-clean water. Water is an essential component in providing effective and safe hemodialysis. Therefore, the dialysis system needs an efficient water purification system .Water has an iatrogenic conversion of dialysate. The water system is mostly out of sight for patients and staff. The dialysate is obtained from ordinary municipal water (Centers for Disease Control, 2018)

The municipal water has a wide variety of molecules and ions, which can be toxic to patients. For example, it has chlorine used to disinfect drinking water. Groundwater has several ions and heavy metals such as magnesium, copper, and aluminum. Surface water has several organic compounds from animal waste and farm runoffs. Water needs to be converted to a dialysate using a series of carbon tanks, deionizers and reverse osmosis (Culligan, 2018).

A carbon tank removes chloramine and chlorine from water, which is added to disinfect water. Chlorine affects the patient’s blood since it forms sodium hypochlorite. Furthermore, it diffuses into the patient where it causes neurologic abnormalities and hemolysis. Moreover, chlorine damages the reverse osmosis equipment. Therefore, carbon filters protect both the machine and the patient (Culligan, 2018).

The first carbon tank removes 100 % of chloramine. Kidney doctors check chloramine levels every four hours in water that exist the first carbon tank. The allowed concentration is 0.1 parts per million. The second carbon tank is used as a backup when the first tank fails (Culligan, 2018).

It is the main workhouse of the water treatment system. It moves water through porous membranes, which is against the solute concentration gradient. Water runs from a low solute concentration region to a higher concentration region during osmosis. However, reverse osmosis is the opposite of osmosis with movement from a high concentration to a low solute concentration. It requires a lot of energy from a pressurized tank. The permeate will be free of organic compounds, ions, viruses, and bacteria (Culligan, 2018).

  It is an optional component during water treatment. Most hemodialysis units rarely use DI tanks because the RO tank removes all ions, solutes, and microorganisms. The DI tank works when the RO breaks down due to a mechanical failure. Therefore, water must pass through the DI tank for H+ and OH- ion exchange. The DI tank exchanges these ions for the cations and anions found in water, an ultra-filter must be fixed to sterilize the water since it does not sterilize water (Culligan, 2018).

Patient education is essential in dialysis. The patient learns various aspects of their conditions and the suitable treatment options. Patients get e educated about dialysis and why they need dialysis. Also, the patients get education information about surgery (Castner, 2008).

Furthermore, the patients are educated on the types of dialysis that is suitable for them depending on their lifestyle and health; this can produce proper choices. Moreover, the patients go to organizations where they can find more support and learn about kidney disease and dialysis such as the National Kidney Foundation. Dialysis centers have free classes for various dialysis choices. The patients can also ask their nephrologists about support groups and classes in their areas.

References

Blowey, D. (2005) Dialysis principles for primary healthcare providers. Clinical Pediatrics Journal, 44(1): 19-27.

Carissa, S. (2017) Hypervolemia (Fluid Overload. Health line.) [Online] Available from https://www.healthline.com/health/health/hypervolemia [Accessed 24th November 20181].

Castner, D. (2008) Patient education series: Kidney dialysis. [Online] Available from https:www.nursingcenter.com/journalarticle?Article_ID=8113308&Journal _ID=54016&Issue_ID=811281 [Accessed 24 November 2018].

Centers for Disease Control. (2018) Water use in hemodialysis. [Online] Available from <https://www.cdc.gov/healthywater/other/medical/hemodialyisis.html [Accessed 24th Nov. 2018].

Culligan. (2018) Medical and Dialysis Water Treatment Systems. [Online] Available from <https://www.culligan.co.uk/commercial-industrial-water-treatment-products/medical-dialysis-water-systems/

Davita Kidney Care. (2018) Arteriovenous fistula. [Online] Available from https://www.davita.com/education/kidney-vocabulary/arteriovenous-fistula [Accessed 24th November 2018.

Gambro. (2018) The AK 96 Machine, Advance Version. [Online] Available from https://www.pdf.medicalexpo.com/pdf/gambro/ak96/70729-68958.html [Accessed 24th Nov. 2018].

Jack, J. & Ravindra, L. (2000) Assessment of Dry Weight in Hemodialysis. Journal of the American Society of Nephrology, 10(2), 392-403.

Mackenzie, T., Zawada, E. (2005) Hemodialysis. Basic principles and practice. Postgrad Medicine, 77(1), 95-101

Mayo Clinic. [2018] Hemodialysis. [Online] Available from https://www.mayo.clinic.org/tests-procedures/hemodialysis/about/pac-20384824 [Accessed 24 November 2018].

National Kidney Foundation. (2018) What is dry weight? [Online] Available from https://www.kidney.org/atoz/content/dry-weight [Accessed 24 November 2018].

Paweena, S. & Bertrand, J. (2017) Hemodialysis: Acute Complications-Dialysis induced Headache. Renal and Urology News. [Online] Available from https://www.renalandurologynews.com/nephrology-hypertension/hemodialysis-acute-complications-dialysis-induced-headache/article/616435/ [Accessed 24 November 24, 2018].

Queen Elizabeth Hospital. (2017) Hemodialysis Blood Results. [Online] Available from https://www.uhb.nhs.uk>Downloads>pdf [Accessed 24^th November 2018].

Watson, D. (2008) Post-dialysis “pre-dialysis” care: the cart before the horse—advanced practice nurse intervention and impact on modality selection. CANNT Journal, 18(1), 30-3.

Yvo, S., Noeleen, C. & Ton, R. (2008) Optimal predialysis care. NDT Plus, 1(4), 7-13.