Peritoneal dialysis | |
---|---|
Specialty | nephrology |
ICD-9-CM | 54.98 |
MeSH | D010530 |
Peritoneal dialysis (PD) is a type of dialysis that uses the peritoneum in a person's abdomen as the membrane through which fluid and dissolved substances are exchanged with the blood. [1] [2] It is used to remove excess fluid, correct electrolyte problems, and remove toxins in those with kidney failure. [3] Peritoneal dialysis has better outcomes than hemodialysis during the first two years. [4] Other benefits include greater flexibility and better tolerability in those with significant heart disease. [4]
Complications may include infections within the abdomen, hernias, high blood sugar, bleeding in the abdomen, and blockage of the catheter. [3] Peritoneal dialysis is not possible in those with significant prior abdominal surgery or inflammatory bowel disease. [3] It requires some degree of technical skill to be done properly. [4]
In peritoneal dialysis, a specific solution is introduced through a permanent tube in the lower abdomen and then removed. [3] This may either occur at regular intervals throughout the day, known as continuous ambulatory peritoneal dialysis (CAPD), or at night with the assistance of a machine, known as automated peritoneal dialysis (APD) [3] or continuous cycling peritoneal dialysis (CCPD). [5] The solution is typically made of sodium chloride, bicarbonate, and an osmotic agent such as glucose. [3]
The solution used for peritoneal dialysis is on the World Health Organization's List of Essential Medicines. [6] [7] As of 2009, peritoneal dialysis was available in 12 of 53 African countries. [8]
Peritoneal dialysis is a method of renal replacement therapy for those needing maintenance therapy for late stage chronic kidney disease and is an alternative to the most common method hemodialysis.
A common cause of peritonitis is touch contamination, e.g. insertion of catheter by un-sanitized hands, which potentially introduces bacteria to the abdomen; other causes include catheter complication, transplantation of bowel bacteria, and systemic infections. [9] Most common type of PD-peritonitis infection (80%) are from bacterial sources. [9] Infection rates are highly variable by region and within centers with estimated rates between 0.06 - 1.66 episodes per patient year. [10] With recent technical advances peritonitis incidence has decreased over time. [11]
Antibiotics are needed if the source of infection is bacterial; there is no clear advantage for other frequently used treatments such as routine peritoneal lavage or use of urokinase. [12] The use of preventative nasal mupirocin is of unclear effect with respect to peritonitis. [13] Of the three types of connection and fluid exchange systems (standard, twin-bag and y-set; the latter two involving two bags and only one connection to the catheter, the y-set uses a single y-shaped connection between the bags involving emptying, flushing out then filling the peritoneum through the same connection) the twin-bag and y-set systems were found superior to conventional systems at preventing peritonitis. [14]
The fluid used for dialysis uses glucose as a primary osmotic agent. According to a 2020 review published in the American Journal of Nephrology, some studies suggest that the use of glucose increases the risk of peritonitis, possibly as a result of impaired host defenses, vascular disease, or damage to the peritoneal membrane. [15] The acidity, high concentration and presence of lactate and products of the degradation of glucose in the solution (particularly the latter) may contribute to these health issues[ ambiguous ]. Solutions that are neutral, use bicarbonate instead of lactate and have few glucose degradation products may offer more health benefits though this has not yet been studied. [16]
The mortality rate of peritoneal dialysis related peritonitis is estimated to be 3-10%, with approximately 50% of cases resulting in hospitalization. [17] Peritoneal fluid studies with a white blood cell count greater than 100 per μL and greater than 50% neutrophils strongly suggest peritonitis, with a definitive diagnosis based on culture of microorganisms from the peritoneal fluid. [17] In order to avoid delaying treatment, a cloudy fluid in the dialysate fluid can be assumed to be due to peritonitis unless an alternative cause is identified. [17] Peritonitis in those undergoing PD is usually due to gram positive bacteria. [17] Intraperitoneal antibiotics are preferred to intravenous as they have a greater effect at the area of infection, unless sepsis is present, in which case intravenous antibiotics are indicated. [17] The peritoneal dialysis catheter may have to be removed if the infection does not resolve with antibiotics, and it is recommended that the PD catheter be removed in all cases of fungal peritonitis. [17]
The volume of dialysate removed as well as patient's weight are monitored. If more than 500ml of fluid are retained or a liter of fluid is lost across three consecutive treatments, the patient's physician is generally notified.[ citation needed ] Excessive loss of fluid can result in hypovolemic shock or hypotension while excessive fluid retention can result in hypertension and edema. Also monitored is the color of the fluid removed: normally it is pink-tinged for the initial four cycles and clear or pale yellow afterward. The presence of pink or bloody effluent suggests bleeding inside the abdomen while feces indicates a perforated bowel and cloudy fluid suggests infection. The patient may also experience pain or discomfort if the dialysate is too acidic, too cold or introduced too quickly, while diffuse pain with cloudy discharge may indicate an infection. Severe pain in the rectum or perineum can be the result of an improperly placed catheter. The dwell can also increase pressure on the diaphragm causing impaired breathing, and constipation can interfere with the ability of fluid to flow through the catheter. [18]
Long term use of PD is rarely associated with fibrosis of the peritoneum. [11] A potentially fatal complication estimated to occur in roughly 2.5% of patients is encapsulating peritoneal sclerosis, in which the bowels become obstructed due to the growth of a thick layer of fibrin within the peritoneum. [19]
Other complications include low back pain and hernia or leaking fluid due to high pressure within the abdomen. [20] Hypertriglyceridemia and obesity are also concerns due to the large volume of glucose in the fluid, which can add 500-1200 calories to the diet per day. [21]
Best practices for peritoneal dialysis state that before peritoneal dialysis should be implemented, the person's understanding of the process and support systems should be assessed, with education on how to care for the catheter and to address any gaps in understanding that may exist. The person should receive ongoing monitoring to ensure adequate dialysis, and be regularly assessed for complications. Finally, they should be educated on the importance of infection control and an appropriate medical regimen established with their cooperation. [22]
The abdomen is cleaned in preparation for surgery and a catheter is surgically inserted with one end in the abdomen and the other protruding from the skin. [23] Catheters can also be inserted without a general anaesthetic by a physician using a needle, known as a medical insertion. Both methods have similar safety profiles. [24] [25] Before each infusion the catheter must be cleaned, and flow into and out of the abdomen tested. 2-3 liters of dialysis fluid is introduced into the abdomen over the next ten to fifteen minutes. [18] The total volume is referred to as a dwell [26] while the fluid itself is referred to as dialysate. The dwell can be as much as 3 liters, and medication can also be added to the fluid immediately before infusion. [18] The dwell remains in the abdomen and waste products diffuse across the peritoneum from the underlying blood vessels. After a variable period of time depending on the treatment (usually 4–6 hours [18] ), the fluid is removed and replaced with fresh fluid. This can occur automatically while the patient is sleeping (automated peritoneal dialysis, APD), or during the day by keeping two litres of fluid in the abdomen at all times, exchanging the fluids four to six times per day (continuous ambulatory peritoneal dialysis, CAPD). [26] [27]
The fluid used typically contains sodium chloride, lactate or bicarbonate and a high percentage of glucose to ensure hyperosmolarity. The amount of dialysis that occurs depends on the volume of the dwell, the regularity of the exchange and the concentration of the fluid. APD cycles between 3 and 10 dwells per night, while CAPD involves four dwells per day of 2-3 liters per dwell, with each remaining in the abdomen for 4–8 hours. The viscera accounts for roughly four-fifths of the total surface area of the membrane, but the parietal peritoneum is the most important of the two portions for PD. Two complementary models explain dialysis across the membrane - the three-pore model (in which molecules are exchanged across membranes which sieve molecules, either proteins, electrolytes or water, based on the size of the pores) and the distributed model (which emphasizes the role of capillaries and the solution's ability to increase the number of active capillaries involved in PD). The high concentration of glucose drives the filtration of fluid by osmosis (osmotic UF) from the peritoneal capillaries to the peritoneal cavity. Glucose diffuses rather rapidly from the dialysate to the blood (capillaries). After 4-6 h of the dwell, the glucose osmotic gradient usually becomes too low to allow for further osmotic UF. Therefore, the dialysate will now be reabsorbed from the peritoneal cavity to the capillaries by means of the plasma colloid osmotic pressure, which exceeds the colloid osmotic pressure in the peritoneum by approximately 18-20 mmHg (cf. the Starling mechanism). [28] Lymphatic absorption will also to some extent contribute to the reabsorption of fluid from the peritoneal cavity to the plasma. Patients with a high water permeability (UF-coefficient) of the peritoneal membrane can have an increased reabsorption rate of fluid from the peritoneum by the end of the dwell. The ability to exchange small solutes and fluid in-between the peritoneum and the plasma can be classified as high (fast), low (slow) or intermediate. High transporters tend to diffuse substances well (easily exchanging small molecules between blood and the dialysis fluid, with somewhat improved results with frequent, short-duration dwells such as with APD), while low transporters have a higher UF (due to the slower reabsorption of glucose from the peritoneal cavity, which results in somewhat better results with long-term, high-volume dwells), though in practice either type of transporter can generally be managed through the appropriate use of either APD or CAPD. [29]
Though there are several different shapes and sizes of catheters that can be used, different insertion sites, number of cuffs in the catheter and immobilization, there is no evidence to show any advantages in terms of morbidity, mortality or number of infections, though the quality of information is not yet sufficient to allow for firm conclusions. [30]
A peritoneal equilibration test may be done to assess a person for peritoneal dialysis by determining the characteristics of the peritoneal membrane mass transport characteristics.
Peritoneal dialysis can be improvised in conditions such as combat surgery or disaster relief using surgical catheters and dialysate made from routinely available medical solutions to provide temporary renal replacement for people with no other options. [31]
As of 2017, hemodialysis is the most widely available renal replacement modality found in 96% of countries whereas peritoneal dialysis (PD) is only available in 75% of countries. [11] In 2016, the proportion of people receiving peritoneal dialysis (PD) was estimated at 11% with wide differences between different countries and regions. [32] In Hong Kong and Mexico, PD is more common than the world average, with Mexico conducting most of its dialysis through PD, while Japan and Germany have rates lower than the world average. [33] Peritoneal dialysis first models, patients requiring renal replacement therapy are placed on PD first, and financial incentives for using PD are associated with increase uptake of PD in multiple countries. [32]
Hong Kong has the highest rate of PD use worldwide at 71.9% in 2014, while in Mainland China had 20% in 2014, 23% in Thailand during 2012, and 10-20% in Vietnam during 2011. [32] Hong Kong had a PD-first model since 1985, Thailand began a PD-first model since 2008 which increased their levels of PD from <10%. [32]
Prevalence in of PD use was 9.7% in USA during 2013 and 16.3% in Canada during 2013. [32] The lower PD rates in the USA are due to higher availability of large corporate owned hemodialysis centers. There have been recent increase in PD uptake in the USA due to changes to medicare reimbursement such as bundled payment for dialysis this incentivizes use of PD which is a less costly modality for dialysis. [32]
Overall, prevalence of PD use is 24.6% in Latin America during 2011. [32] Within Latin America, hemodialysis has a higher growth rate in use compared to PD between 1994 - 2010. In 2010, the most prevalent use of PD were in Mexico 55.9% and El Salvador 67.6%. Between 2000 - 2010, Colombia's PD rate dropped from 54% to 31.3%. [34]
Peritoneal dialysis was first carried out in the 1920s; however, long-term use did not come into medical practice until the 1960s. [35] The timeline was
Compared to hemodialysis, PD allows greater patient mobility, produces fewer swings in symptoms due to its continuous nature, and phosphate compounds are better removed, but large amounts of albumin are removed which requires constant monitoring of nutritional status. [11] The costs of PD are generally lower than those of HD in most parts of the world, this cost advantage is most apparent in developed economies. [41] There is insufficient research to adequately compare the risks and benefits between CAPD and APD; a Cochrane Review of three small clinical trials found no difference in clinically important outcomes (i.e. morbidity or mortality) for patients with end stage renal disease, nor was there any advantage in preserving the functionality of the kidneys. The results suggested APD may have psychosocial advantages for younger patients and those who are employed or pursuing an education. [42] [ needs update ]
PD may also be used for patients with cardiac instability as it does not result in rapid and significant alterations to body fluids, and for patients with insulin-dependent diabetes mellitus due to the inability to control blood sugar levels through the catheter.
The cost of dialysis treatment is related to how wealthy the country is. [8] In the United States peritoneal dialysis costs the government about $53,400 per person per year. [4]
In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and right in the retroperitoneal space, and in adult humans are about 12 centimetres in length. They receive blood from the paired renal arteries; blood exits into the paired renal veins. Each kidney is attached to a ureter, a tube that carries excreted urine to the bladder.
Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common, life-threatening inherited human disorders and the most common hereditary kidney disease. It is associated with large interfamilial and intrafamilial variability, which can be explained to a large extent by its genetic heterogeneity and modifier genes. It is also the most common of the inherited cystic kidney diseases — a group of disorders with related but distinct pathogenesis, characterized by the development of renal cysts and various extrarenal manifestations, which in case of ADPKD include cysts in other organs, such as the liver, seminal vesicles, pancreas, and arachnoid membrane, as well as other abnormalities, such as intracranial aneurysms and dolichoectasias, aortic root dilatation and aneurysms, mitral valve prolapse, and abdominal wall hernias. Over 50% of patients with ADPKD eventually develop end stage kidney disease and require dialysis or kidney transplantation. ADPKD is estimated to affect at least one in every 1000 individuals worldwide, making this disease the most common inherited kidney disorder with a diagnosed prevalence of 1:2000 and incidence of 1:3000-1:8000 in a global scale.
The peritoneum is the serous membrane forming the lining of the abdominal cavity or coelom in amniotes and some invertebrates, such as annelids. It covers most of the intra-abdominal organs, and is composed of a layer of mesothelium supported by a thin layer of connective tissue. This peritoneal lining of the cavity supports many of the abdominal organs and serves as a conduit for their blood vessels, lymphatic vessels, and nerves.
Kidney dialysis is the process of removing excess water, solutes, and toxins from the blood in people whose kidneys can no longer perform these functions naturally. Along with kidney transplantation, it is a type of renal replacement therapy.
Peritonitis is inflammation of the localized or generalized peritoneum, the lining of the inner wall of the abdomen and cover of the abdominal organs. Symptoms may include severe pain, swelling of the abdomen, fever, or weight loss. One part or the entire abdomen may be tender. Complications may include shock and acute respiratory distress syndrome.
Kidney failure, also known as end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as either acute kidney failure, which develops rapidly and may resolve; and chronic kidney failure, which develops slowly and can often be irreversible. Symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications of acute and chronic failure include uremia, hyperkalemia, and volume overload. Complications of chronic failure also include heart disease, high blood pressure, and anaemia.
Uremia is the condition of having high levels of urea in the blood. Urea is one of the primary components of urine. It can be defined as an excess in the blood of amino acid and protein metabolism end products, such as urea and creatinine, which would normally be excreted in the urine. Uremic syndrome can be defined as the terminal clinical manifestation of kidney failure. It is the signs, symptoms and results from laboratory tests which result from inadequate excretory, regulatory, and endocrine function of the kidneys. Both uremia and uremic syndrome have been used interchangeably to denote a very high plasma urea concentration that is the result of renal failure. The former denotation will be used for the rest of the article.
Hemodialysis, also spelled haemodialysis, or simply dialysis, is a process of filtering the blood of a person whose kidneys are not working normally. This type of dialysis achieves the extracorporeal removal of waste products such as creatinine and urea and free water from the blood when the kidneys are in a state of kidney failure. Hemodialysis is one of three renal replacement therapies. An alternative method for extracorporeal separation of blood components such as plasma or cells is apheresis.
Home hemodialysis (HHD) is the provision of hemodialysis to purify the blood of a person whose kidneys are not working normally, in their own home. One advantage to doing dialysis at home is that it can be done more frequently and slowly, which reduces the "washed out" feeling and other symptoms caused by rapid ultrafiltration, and it can often be done at night, while the person is sleeping.
Hepatorenal syndrome (HRS) is a life-threatening medical condition that consists of rapid deterioration in kidney function in individuals with cirrhosis or fulminant liver failure. HRS is usually fatal unless a liver transplant is performed, although various treatments, such as dialysis, can prevent advancement of the condition.
In medicine, Kt/V is a number used to quantify hemodialysis and peritoneal dialysis treatment adequacy.
Artificial kidney is often a synonym for hemodialyzer, but may also refer to the other renal replacement therapies that are in use and/or in development. This article deals mainly with bio-artificial kidneys featuring cells that are grown from renal cell lines/renal tissue.
Hemofiltration, also haemofiltration, is a renal replacement therapy which is used in the intensive care setting. It is usually used to treat acute kidney injury (AKI), but may be of benefit in multiple organ dysfunction syndrome or sepsis. During hemofiltration, a patient's blood is passed through a set of tubing via a machine to a semipermeable membrane where waste products and water are removed by convection. Replacement fluid is added and the blood is returned to the patient.
Renal replacement therapy (RRT) is therapy that replaces the normal blood-filtering function of the kidneys. It is used when the kidneys are not working well, which is called kidney failure and includes acute kidney injury and chronic kidney disease. Renal replacement therapy includes dialysis, hemofiltration, and hemodiafiltration, which are various ways of filtration of blood with or without machines. Renal replacement therapy also includes kidney transplantation, which is the ultimate form of replacement in that the old kidney is replaced by a donor kidney.
In nephrology, the peritoneal equilibration test (PET), is a tool used by nephrologists to determine the characteristics of the peritoneal membrane mass transport characteristics, when assessing a patient for peritoneal dialysis.
Icodextrin is a colloid osmotic agent, derived from maltodextrin, used in form of an aqueous solution for peritoneal dialysis under the trade name Extraneal, and after gynecological laparoscopic surgery for the reduction of post-surgical adhesions under the trade name Adept.
Northwest Kidney Centers is a regional, not-for-profit community-based provider of kidney dialysis, public health education, and research into the causes and treatments of chronic kidney disease. Established in Seattle in 1962, it was the world's first out-of-hospital dialysis provider. It offers dialysis throughout the greater Seattle area in 20 free-standing clinics, eight hospitals and its home dialysis program. It opened its first clinic in Everett in 2020, the organization's first in Snohomish county.
Many conditions are associated with disorders of the function of the parathyroid gland. Some disorders may be purely anatomical resulting in an enlarged gland which will raise concern. Such benign disorders, such as parathyroid cyst, are not discussed here. Parathyroid diseases can be divided into those causing hyperparathyroidism, and those causing hypoparathyroidism.
Catheter lock solution is a solution put into catheters to fill the catheter when not in use, primarily to prevent clotting. Neutrolin is an anti-microbial catheter lock solution developed by Cormedix/Cormedix GmbH. Neutrolin contains heparin and citrate, two compounds commonly used to prevent thrombosis and maintain catheter patency. Other brand names include Citra-Lock and Taurolock.
Encapsulating peritoneal sclerosis(EPS) is a chronic clinical syndrome with an insidious onset that manifests as chronic undernourishment accompanied by sporadic, acute, or subacute gastrointestinal obstruction symptoms. Peritoneal dialysis is most commonly linked to encapsulating peritoneal sclerosis, especially when peritoneal dialysis is stopped. The diagnosis is verified by macroscopic and/or radiological observations of intestinal encapsulation, calcification, thickening of the peritoneum, or sclerosis.