Peritoneal Dialysis and Hemodialysis

Overview

Definition

Dialysis is a form of renal replacement therapy (RRT) that is used to perform the blood-filtering role of the kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy when the kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy are not functioning.

• The conditions generally include:
  • AKI AKI Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury
  • CKD CKD Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. Hypertension and diabetes are the most common causes; however, there are a multitude of other etiologies. In the early to moderate stages, CKD is usually asymptomatic and is primarily diagnosed by laboratory abnormalities. Chronic Kidney Disease
• Types:
  • Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome
  • Peritoneal dialysis

Indications for dialysis in acute kidney injury Acute Kidney Injury Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury

Acute kidney injury Acute Kidney Injury Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury is sometimes so severe that dialysis is needed as a life-support measure while waiting for possible renal recovery.

• Dialysis is a temporizing measure that is used with the hope that the patient will recover enough renal function to allow dialysis to be discontinued permanently.
• Some patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with AKI AKI Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury do not recover renal function and require long-term RRT.

Indications:

• Signs of uremia Uremia A clinical syndrome associated with the retention of renal waste products or uremic toxins in the blood. It is usually the result of renal insufficiency. Most uremic toxins are end products of protein or nitrogen catabolism, such as urea or creatinine. Severe uremia can lead to multiple organ dysfunctions with a constellation of symptoms. Acute Kidney Injury
• Severe hyperkalemia Hyperkalemia Hyperkalemia is defined as a serum potassium (K+) concentration >5.2 mEq/L. Homeostatic mechanisms maintain the serum K+ concentration between 3.5 and 5.2 mEq/L, despite marked variation in dietary intake. Hyperkalemia can be due to a variety of causes, which include transcellular shifts, tissue breakdown, inadequate renal excretion, and drugs. Hyperkalemia
• Severe metabolic acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis
• Volume overload refractory to diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication
• Acute poisonings: 
  • Lithium Lithium An element in the alkali metals family. It has the atomic symbol li, atomic number 3, and atomic weight [6. 938; 6. 997]. Salts of lithium are used in treating bipolar disorder. Ebstein’s Anomaly
  • Toxic alcohols ( ethylene glycol Ethylene glycol A colorless, odorless, viscous dihydroxy alcohol. It has a sweet taste, but is poisonous if ingested. Ethylene glycol is the most important glycol commercially available and is manufactured on a large scale in the United States. It is used as an antifreeze and coolant, in hydraulic fluids, and in the manufacture of low-freezing dynamites and resins. Nephrolithiasis, methanol Methanol A colorless, flammable liquid used in the manufacture of formaldehyde and acetic acid, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness. Metabolic Acidosis)

Indications for dialysis in chronic kidney disease Chronic Kidney Disease Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. Hypertension and diabetes are the most common causes; however, there are a multitude of other etiologies. In the early to moderate stages, CKD is usually asymptomatic and is primarily diagnosed by laboratory abnormalities. Chronic Kidney Disease

• Chronic kidney disease Chronic Kidney Disease Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. Hypertension and diabetes are the most common causes; however, there are a multitude of other etiologies. In the early to moderate stages, CKD is usually asymptomatic and is primarily diagnosed by laboratory abnormalities. Chronic Kidney Disease is often progressive, such that patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship will reach end-stage renal disease (ESRD) and then require dialysis or kidney transplantation Kidney Transplantation The transference of a kidney from one human or animal to another. Organ Transplantation.
• The decision to start chronic dialysis is individualized based on uremic symptoms and lab results.  
• Consensus statements from Kidney Disease: Improving Global Outcomes (KDIGO) and Kidney Disease Outcomes Quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement Initiative (KDOQI) help guide these decisions, considering the following factors:  
  • GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests < 15 mL/min
  • Uremic symptoms:
    • Encephalopathy Encephalopathy Hyper-IgM Syndrome
    • Serositis Serositis Inflammation of a serous membrane. Systemic Lupus Erythematosus ( pericarditis Pericarditis Pericarditis is an inflammation of the pericardium, often with fluid accumulation. It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma. Acute, subacute, and chronic forms exist. Pericarditis/ pleuritis Pleuritis Pleuritis, also known as pleurisy, is an inflammation of the visceral and parietal layers of the pleural membranes of the lungs. The condition can be primary or secondary and results in sudden, sharp, and intense chest pain on inhalation and exhalation. Pleuritis)
    • Worsening nutritional status
  • Hypervolemia Hypervolemia Renal Sodium and Water Regulation that is uncontrollable with diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication
  • Electrolyte abnormalities (primarily hyperkalemia Hyperkalemia Hyperkalemia is defined as a serum potassium (K+) concentration >5.2 mEq/L. Homeostatic mechanisms maintain the serum K+ concentration between 3.5 and 5.2 mEq/L, despite marked variation in dietary intake. Hyperkalemia can be due to a variety of causes, which include transcellular shifts, tissue breakdown, inadequate renal excretion, and drugs. Hyperkalemia) that are uncontrollable with medications
  • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension that is uncontrollable with medications

Principles

Dialysis, which depends on the principles of diffusion and ultrafiltration through a semipermeable membrane, can be administered through two distinct mechanisms:

• Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome: The semipermeable membrane is the synthetic dialysis filter.
• Peritoneal dialysis ( PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease): The semipermeable membrane is the patient’s peritoneal membrane.

Definitions:

• Semipermeable membrane:
  • A membrane that is permeable to some, but not all, solutes
  • Permeability may be determined by size and/or charge of the solutes.
  • Necessary for the concept of concentration gradients 
• Diffusion: movement of solutes across a semipermeable membrane from areas of high concentration to areas of low concentration
• Ultrafiltration: 
  • Movement of water across a semipermeable membrane
  • In dialysis, this occurs with water moving from a place of higher pressure (the blood) to a place of lower pressure (the dialysate).

Introduction to Hemodialysis

Overview

Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome is a procedure by which waste products and excess water are removed from a patient’s blood. This is done by directly removing blood from the patient’s circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment, passing it through the dialysis filter, and then returning it directly back into the circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment.
Apparatus needed:

• Dialyzer or dialysis filter
• Dialysate (dialysis solution)
• Tubing for transport of blood and dialysate
• Machine that powers and monitors the filtration

Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome access

• Provides direct access to the patient’s circulatory system via the large central veins Central Veins Central Venous Catheter 
• Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome cannot be performed without an adequately functioning access point. 
• Two basic types: 
  • Central venous catheters Central Venous Catheters Catheters that are inserted into a large central vein such as a subclavian vein or femoral vein. Central Venous Catheter 
  • Permanent access points (i.e., arteriovenous fistula Arteriovenous fistula An abnormal direct communication between an artery and a vein without passing through the capillaries. An a-v fistula usually leads to the formation of a dilated sac-like connection, arteriovenous aneurysm. The locations and size of the shunts determine the degree of effects on the cardiovascular functions such as blood pressure and heart rate. Vascular Surgery)

Central venous catheters Central Venous Catheters Catheters that are inserted into a large central vein such as a subclavian vein or femoral vein. Central Venous Catheter

• Large bore (usually 11–13 French) allows for the faster flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure rates needed for dialysis.
  • Usually inserted into the internal jugular vein Internal jugular vein Parapharyngeal Abscess or femoral vein
  • Can be nontunneled or tunneled (underneath the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions)
• Nontunneled dialysis catheters:
  • Commonly referred to as “Quinton catheters” or “temporary dialysis catheters”
  • Most commonly placed in hospital settings for AKI AKI Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury
  • Secured to the patient only with sutures and surgical dressing
  • Intended to stay in place for only a period of days:
    • High risk of infection over time
    • Significant bleeding risk if inadvertently dislodged
  • Patient may not be discharged from the hospital with this type of catheter.
• Tunneled dialysis catheters (TDC):
  • Also known as “Hickman catheters” or “permacaths”
  • Not considered permanent access
  • Used for patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who need chronic dialysis started urgently (serving as a “bridge”), but do not yet have a permanent access (i.e., arteriovenous fistula Arteriovenous fistula An abnormal direct communication between an artery and a vein without passing through the capillaries. An a-v fistula usually leads to the formation of a dilated sac-like connection, arteriovenous aneurysm. The locations and size of the shunts determine the degree of effects on the cardiovascular functions such as blood pressure and heart rate. Vascular Surgery)
  • Usually inserted into internal jugular vein Internal jugular vein Parapharyngeal Abscess 
  • Catheter is tunneled subcutaneously and exits the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions underneath the clavicle Clavicle A bone on the ventral side of the shoulder girdle, which in humans is commonly called the collar bone. Clavicle Fracture.
  • Secured to patient via a “cuff”:
    • Synthetic material around the part of the catheter that rests underneath the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions near the exit site
    • Fibrosis Fibrosis Any pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury. Bronchiolitis Obliterans develops around the cuff and surrounding subcutaneous tissue Subcutaneous tissue Loose connective tissue lying under the dermis, which binds skin loosely to subjacent tissues. It may contain a pad of adipocytes, which vary in number according to the area of the body and vary in size according to the nutritional state. Soft Tissue Abscess, holding the catheter in place and serving as a barrier to infection.
  • May be left in place for a period of several weeks.
    • Patient may be discharged from the hospital with this type of catheter.
    • Less risk for infection as compared with nontunneled catheters
    • Overall risk for infection is still significant, particularly if left in place for long periods.
    • Removed once permanent dialysis access is functional

Permanent access

Permanent dialysis access points allow dialysis for the long term (i.e., years) and include arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs).

Arteriovenous fistula Arteriovenous fistula An abnormal direct communication between an artery and a vein without passing through the capillaries. An a-v fistula usually leads to the formation of a dilated sac-like connection, arteriovenous aneurysm. The locations and size of the shunts determine the degree of effects on the cardiovascular functions such as blood pressure and heart rate. Vascular Surgery:

• Ideal type of access for chronic hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome:
  • Least risk of infection
  • Longest lasting
• Direct surgical connection (i.e., anastomosis) of an artery and a vein, most commonly: 
  • Radial artery Radial Artery The direct continuation of the brachial trunk, originating at the bifurcation of the brachial artery opposite the neck of the radius. Its branches may be divided into three groups corresponding to the three regions in which the vessel is situated, the forearm, wrist, and hand. Forearm: Anatomy to cephalic vein
  • Brachial artery Brachial Artery The continuation of the axillary artery; it branches into the radial and ulnar arteries. Cubital Fossa: Anatomy to cephalic vein
  • Brachial artery Brachial Artery The continuation of the axillary artery; it branches into the radial and ulnar arteries. Cubital Fossa: Anatomy to basilic vein Basilic vein Arm: Anatomy
  • Lower-extremity AVFs are also possible.
• High pressure from the artery is transmitted directly into the vein, instead of being dispersed throughout a capillary bed.
  • Results in vein changing anatomically (i.e., thickening, or “arterializing”) to resemble an artery, which takes weeks to occur
  • This process is known as “maturation” of the fistula Fistula Abnormal communication most commonly seen between two internal organs, or between an internal organ and the surface of the body. Anal Fistula; AVF cannot be used during this period.
  • Necessary because normal veins Veins Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia. Veins: Histology will either collapse or blow out under the high fluid flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure rates needed for dialysis
• Poor candidates for AVF:
  • Inadequate or small veins Small veins Veins: Histology
  • History of AVFs that do not mature adequately
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with multiple failed AVFs and no other locations available for AVF

Arteriovenous graft Graft A piece of living tissue that is surgically transplanted Organ Transplantation:

• Better for chronic dialysis than TDC, but not as good as AVF
• Indirect surgical connection of an artery and vein using a tube of prosthetic material
• Many possible locations: forearm Forearm The forearm is the region of the upper limb between the elbow and the wrist. The term “forearm” is used in anatomy to distinguish this area from the arm, a term that is commonly used to describe the entire upper limb. The forearm consists of 2 long bones (the radius and the ulna), the interosseous membrane, and multiple arteries, nerves, and muscles. Forearm: Anatomy, upper arm Upper Arm The arm, or “upper arm” in common usage, is the region of the upper limb that extends from the shoulder to the elbow joint and connects inferiorly to the forearm through the cubital fossa. It is divided into 2 fascial compartments (anterior and posterior). Arm: Anatomy, chest, thigh Thigh The thigh is the region of the lower limb found between the hip and the knee joint. There is a single bone in the thigh called the femur, which is surrounded by large muscles grouped into 3 fascial compartments. Thigh: Anatomy
• Advantages compared with AVF:
  • Much shorter maturation period (can hypothetically be used immediately, though usually wait approximately 2 weeks before initial use)
  • Dialysis needles are placed directly into the synthetic graft Graft A piece of living tissue that is surgically transplanted Organ Transplantation material.
  • Can be placed in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who are poor candidates for AVF
  • Can be placed in more anatomic locations than AVFs (i.e., chest)
• Disadvantages compared with AVF:
  • Higher risk of infection owing to synthetic material residing inside the body
  • Higher risk of clotting

The Process of Hemodialysis

Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome procedure

1. Two sets of tubing are connected to the patient’s dialysis access:
   • Connected directly to central venous catheter Central Venous Catheter Central venous catheters are IV lines placed into the large central veins for monitoring of central venous pressure (CVP), prolonged drug administration, or administration of parenteral nutrition. The most common sites of insertion are the internal jugular and subclavian veins. Central Venous Catheter
   • Two needles inserted into AVF/AVG and taped down
2. Azotemic blood pumped from patient into dialysis filter 
3. Dialysis filter removes toxins primarily through diffusion:  
   • Dialysis filter is a plastic cylinder filled with thousands of tiny individual tubes composed of the filtering material.
   • Blood flows through the inside of the tiny tubes in one direction.
   • Dialysis fluid (dialysate) flows on the outside of the tiny tubes (but still within the single plastic cylinder that contains them) in the opposite direction.
   • The opposing directions of blood and dialysate result in maximal concentration gradients that drive the diffusion of toxins:
     • Known as “countercurrent” mechanism
     • Also results in correction of electrolyte/acid–base abnormalities via diffusion 
4. Dialysis filter removes excess water from the blood through ultrafiltration.
   • Suction force is applied by the dialysis machine across the dialysis filter.
   • Water is pulled from the blood side into the dialysate side. 
5. Clean blood and waste-filled dialysate exit the dialysis filter.
   • Clean blood is pumped back into the patient’s circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment.
   • Waste-filled dialysate is disposed of (including the excess water from the patient’s body that was removed during ultrafiltration).
6. Overall process continues until the end of the treatment session.
   • Chronic dialysis
     • 3–4 hours each session
     • 3 times a week (Monday/Wednesday/Friday or Tuesday/Thursday/Saturday)
   • Acute dialysis: Treatment duration and daily schedule are variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables.

Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome prescription

The nephrologist may control many variables within the dialysis procedure:

• Duration of treatment 
• Ultrafiltration goal
• Anticoagulation Anticoagulation Pulmonary Hypertension Drugs:
  • Blood is prone to clotting as it travels through the plastic tubing and dialysis membrane.
  • When cloting occurs, the treatment must be stopped and reset, which limits the overall treatment time and effectiveness.
  • IV heparin is often used to help prevent this clotting of the dialysis circuit.
• Electrolyte composition of the dialysate: 
  • Potassium Potassium An element in the alkali group of metals with an atomic symbol k, atomic number 19, and atomic weight 39. 10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the water-electrolyte balance. Hyperkalemia can be set between 0 and 4 mEq/L.
  • Sodium Sodium A member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23. Hyponatremia can be set between 130 and 145 mEq/L.
  • Calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes can be set between 2.5 and 3.5 mEq/L.
  • Bicarbonate Bicarbonate Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the ph of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity. Electrolytes can be set between 30 and 40 mEq/L.
• Speed of blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure and dialysate flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure:
  • Blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure ranges from 250 to 450 mL/min.
  • Dialysate flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure ranges from 500 to 800 mL/min.

Introduction to Peritoneal Dialysis

Overview

• Peritoneal dialysis achieves the same net result as hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome (the removal of toxins and excess water); however, the process is completely different.  
• Instead of removing blood from the patient, filtering it externally, and then returning it to the patient, the filtration occurs within the patient’s abdominal cavity.
• The only fluid moving in and out of the patient’s body is the dialysate.

Anatomical considerations

Anatomy of the abdomen can be simply thought of as including:

• Intraperitoneal Intraperitoneal Peritoneum: Anatomy space
• Abdominal organs
• The peritoneal membrane, which lines the intraperitoneal Intraperitoneal Peritoneum: Anatomy space and abdominal organs, functions as the dialysis filter:
  • Semipermeable membrane
  • Capillaries Capillaries Capillaries are the primary structures in the circulatory system that allow the exchange of gas, nutrients, and other materials between the blood and the extracellular fluid (ECF). Capillaries are the smallest of the blood vessels. Because a capillary diameter is so small, only 1 RBC may pass through at a time. Capillaries: Histology on one side
  • Dialysate inside the intraperitoneal Intraperitoneal Peritoneum: Anatomy space on the other side
• Peritoneal dialysis ( PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease) catheter:
  • Surgically inserted through the abdomen
  • Allows direct access for the insertion and drainage of dialysis fluid
  • Inside the body, the catheter tip is curled and rests in the intraperitoneal Intraperitoneal Peritoneum: Anatomy space.
  • Outside the body, the catheter extends several inches from the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions.

Peritoneal dialysis access

• Provides direct access to the peritoneal space via a surgically implanted catheter
• Unlike hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome, there is only one basic type of PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease access: the PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease catheter:
  • Surgically implanted through the abdominal wall Abdominal wall The outer margins of the abdomen, extending from the osteocartilaginous thoracic cage to the pelvis. Though its major part is muscular, the abdominal wall consists of at least seven layers: the skin, subcutaneous fat, deep fascia; abdominal muscles, transversalis fascia, extraperitoneal fat, and the parietal peritoneum. Surgical Anatomy of the Abdomen
  • Utilizes a cuff system to hold it in place, similar to TDC
  • Can be used immediately if urgently needed, but usually wait approximately 2 weeks after surgery

Peritoneal dialysis fluid

• Not the same as is used for hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome!
• The dialysate from PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease is very hypertonic Hypertonic Solutions that have a greater osmotic pressure than a reference solution such as blood, plasma, or interstitial fluid. Renal Sodium and Water Regulation to the patient’s blood (the dialysate from hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome is isotonic Isotonic Solutions having the same osmotic pressure as blood serum, or another solution with which they are compared. Renal Sodium and Water Regulation).
  • Hypertonicity Hypertonicity Volume Depletion and Dehydration is the result of very high glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance concentrations.
  • Creates a concentration gradient for ultrafiltration

Process of Peritoneal Dialysis

Peritoneal dialysis procedure

1. Dialysate is inserted into the peritoneal space through the PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease catheter.
2. Dialysate and blood interact with the peritoneal membrane. 
3. Toxins and water move from the blood side to the dialysate side via diffusion:
   • Toxin concentrations are high in the blood and zero in the dialysate. 
   • Tonicity Tonicity Plasma tonicity refers to the concentration of only the osmotically active solutes in blood Renal Sodium and Water Regulation of blood (i.e., water concentration) is lower than that of the high-tonicity dialysate. 
   • Electrolyte/acid–base abnormalities also are corrected via diffusion. 
   • After several hours, the two sides equilibrate and no further net transport occurs.
4. Equilibrated dialysate (including the toxins and excess water from the blood) is removed from the peritoneal space through the PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease catheter.
5. The process is repeated several times per session.

Methods of peritoneal dialysis

There are two basic methods to perform peritoneal dialysis:

• Continuous ambulatory peritoneal dialysis (CAPD)
• Automated peritoneal dialysis

Both methods utilize the same catheter and generally have the same clinical results, with selection Selection Lymphocyte activation by a specific antigen thus triggering clonal expansion of lymphocytes already capable of mounting an immune response to the antigen. B cells: Types and Functions dependent on patient preference.

The primary difference is the use of a machine (called a “cycler”) in automated peritoneal dialysis to automatically pump Pump ACES and RUSH: Resuscitation Ultrasound Protocols the dialysis fluid into and out of the body.

Continuous ambulatory peritoneal dialysis:

• Does not use a machine
• Gravity is used to allow dialysate to flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure into and out of the intraperitoneal Intraperitoneal Peritoneum: Anatomy space:
  • Bag of fresh dialysate is hung above the patient.
  • Drainage bag for spent dialysate rests below the patient.
• Treatment is done throughout the day:
  • Patient uses sterile Sterile Basic Procedures technique to connect PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease catheter tubing to dialysate bag.
  • Approximately 2 L of dialysate are inserted into the abdomen.
  • Patient uses sterile Sterile Basic Procedures technique to disconnect from the dialysate bag.
  • Patient can ambulate and go about their normal day while the fluid acts.
  • Several hours later (dwell time), the patient uses sterile Sterile Basic Procedures technique to connect to the drainage bag and dialysate bag.
  • Patient drains the spent dialysate from the abdomen into the drainage bag.
  • Patient refills the abdomen with fresh dialysate (process known as an “exchange”).
• Pros:
  • No machine needed
  • Patient not continuously attached to apparatus for many hours
  • Patient less likely to have sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disturbed by dialysis (treatment is during the day)
• Cons CoNS Staphylococcus: 
  • More work for the patient
  • Must connect and disconnect multiple times per day, increasing the chance for touch contamination
  • Patient must monitor the dwell time.
  • Fluid that goes in and out of the abdomen must be measured; too much fluid in will be uncomfortable (net fluid removed is the ultrafiltration volume).

Automated peritoneal dialysis:

• Uses a machine (cycler) to transfer fluid into and out of the peritoneal space
• Treatment is done primarily at night.
  • Patient uses sterile Sterile Basic Procedures technique to connect PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease catheter to the cycler.
  • Cycler is turned on, and patient goes to sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep.
  • Cycler automatically pumps approximately 2 L of dialysate into the abdomen.
  • Dialysate dwells for several hours.
  • Cycler automatically pumps the spent dialysate out.
  • Process repeats with fresh dialysate.
  • When the patient wakes up, they detach from the cycler and the process is finished.
• Pros:
  • Less work for patient, as the cycler measures fluid volumes in and out 
  • Patient can review data (ultrafiltration volume) on the cycler after treatment.
  • Patient connects/disconnects only two times per session, so less chance for touch contamination.
  • Can function during daytime without having to stop for drain/fill procedure (i.e., exchanges)
• Cons CoNS Staphylococcus:
  • Cost and maintenance of the cycler
  • Must be attached to cycler for 8–10 hours consecutively
  • May interrupt sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep

Peritoneal dialysis prescription

Considerations:

• The variables for the PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease prescription are much different from those for the hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome prescription.  
• After choosing between automated peritoneal dialysis and CAPD, the primary variables are:
  • Strength of dialysate used
  • Number of exchanges per session
  • Length of each exchange
• It takes several weeks after changing the PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease prescription to determine its effect, unlike the hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome prescription, which can be monitored after each session.

Prescription contents:

• Automated peritoneal dialysis versus CAPD
• Number of exchanges per session (usually 4–5)
• Dwell time per exchange: 
  • 4–6 hours for CAPD
  • 1–3 hours for automated peritoneal dialysis
• Dwell volume (usually approximately 2 L, but can be increased)
• Dialysate strength:
  • 3 options if dextrose Dextrose Intravenous Fluids is used as the osmotic agent:
    • 1.25% dextrose Dextrose Intravenous Fluids, 2.5% dextrose Dextrose Intravenous Fluids, 4.25% dextrose Dextrose Intravenous Fluids
    • Osmolality Osmolality Plasma osmolality refers to the combined concentration of all solutes in the blood. Renal Sodium and Water Regulation is 346, 396, and 485, respectively.
    • Higher strength results in more ultrafiltration.
  • 1 option if dextrose Dextrose Intravenous Fluids is not used as the osmotic agent: icodextrin
    • Colloid Colloid Colloid solutions include large proteins or cells that do not readily cross capillary membranes. They remain in the ecf and do not distribute into the icf (similar to crystalloids). Intravenous Fluids
    • Less commonly used than dextrose Dextrose Intravenous Fluids solutions
  • Bags are color coded to help in patient/physician communication Communication The exchange or transmission of ideas, attitudes, or beliefs between individuals or groups. Decision-making Capacity and Legal Competence.
    • 1.25% dextrose Dextrose Intravenous Fluids (yellow), 2.5% dextrose Dextrose Intravenous Fluids (green), 4.25% dextrose Dextrose Intravenous Fluids (red)
    • Icodextrin (purple)
    • Example: Physician may instruct the patient to switch from green bag to red bag if more ultrafiltration is needed.
  • Other components (i.e., electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes, base buffer) are standardized and not commonly manipulated.

Choice of Method

Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome versus peritoneal dialysis

• Studies have failed to show overall, long-term differences in outcomes (including mortality Mortality All deaths reported in a given population. Measures of Health Status) between hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome and peritoneal dialysis.  
• The decision between the two methods comes down to patient preference, based on the factors below.

Pros and cons CoNS Staphylococcus of hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome

Pros:

• Not work-intensive for the patient: 
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship do not have to connect themselves to the dialysis machine.
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship do not have to operate or monitor the dialysis machine.
• Changes to dialysis prescription can be assessed for quickly.
  • Ultrafiltration goal can be changed every session if extra fluid weight is gained.
  • Time can be added to a session, if needed.
  • Electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes can be manipulated each session.

Cons CoNS Staphylococcus:

• Some patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship have long-term issues with hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome access:
  • Arteriovenous fistulas can fail to mature and require multiple surgeries.
  • Arteriovenous fistulas/arteriovenous grafts can clot and require declotting procedures.
  • Tunneled dialysis catheter can get infected.
• Must spend considerable time in dialysis unit (approximately 9–12 hours) 
• Must have adequate transportation to and from the dialysis unit
• Residual renal function is lost more quickly than with PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease.
• Must be stricter with oral fluid restriction:
  • Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship tend to have minimal residual urine output.
  • Hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship tend to have minimal response to oral diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication.
  • All fluid that the patient drinks between dialysis treatments (approximately 48 hours) must be removed during the following treatment.
• Some have significant issues with adverse effects:
  • Intradialytic hypotension Intradialytic hypotension Hypotension
  • Muscle cramps Cramps Ion Channel Myopathy

Pros and cons CoNS Staphylococcus of peritoneal dialysis

Pros:

• Occurs at home
• Can adjust life around dialysis more easily than with hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome:
  • Many patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship on PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease continue to work, which is less common for those on hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome.
  • Dialysis takes place only at night with cycler
• Residual renal function is lost more slowly than with hemodialysis Hemodialysis Procedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys. Crush Syndrome.
• Can be more liberal with oral fluid restriction:
  • With PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease, patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship tend to have significant urine output and will respond to oral diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication.
  • With PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease, patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship dialyze 7 days a week, with the fluid from only the previous 24 hours needing to be removed with each treatment.

Cons CoNS Staphylococcus:

• Very work-intensive for the patient:
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship must connect themselves to and disconnect themselves from the dialysis apparatus.
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship must always use strict sterile Sterile Basic Procedures technique and avoid touch contamination.
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship must monitor dialysis process (dwell time, ultrafiltration).
  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship must make sure they do not run out of supplies. 
• Peritonitis Peritonitis Inflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs. Penetrating Abdominal Injury:
  • Infection of the peritoneal space
  • Very painful
  • Usually due to touch contamination during the connect/disconnect process
  • Treated with antibiotics that can be added to the dialysate bags
• Hyperglycemia Hyperglycemia Abnormally high blood glucose level. Diabetes Mellitus:
  • Dextrose Dextrose Intravenous Fluids solutions cause varying degrees of hyperglycemia Hyperglycemia Abnormally high blood glucose level. Diabetes Mellitus, depending on strength.
  • Can limit Limit A value (e.g., pressure or time) that should not be exceeded and which is specified by the operator to protect the lung Invasive Mechanical Ventilation the utility of PD PD Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease if patient is diabetic ( insulin Insulin Insulin is a peptide hormone that is produced by the beta cells of the pancreas. Insulin plays a role in metabolic functions such as glucose uptake, glycolysis, glycogenesis, lipogenesis, and protein synthesis. Exogenous insulin may be needed for individuals with diabetes mellitus, in whom there is a deficiency in endogenous insulin or increased insulin resistance. Insulin requirements will increase)
• Changes to dialysis prescription take several weeks to take effect.