Question

In peritoneal dialysis (a) the blood is removed from the body and a natural filter is used (b) the blood is not removed from the body and a natural filter is used (c) the blood is not removed from the body and an artificial filter is used (d) the blood is removed from the body and an artificial filter is used

Short answer

(b) the blood is not removed from the body and a natural filter is used.

Step-by-step solution

Understanding the Concept of Dialysis

Dialysis is a medical treatment for kidney failure that removes waste products and excess fluid from the blood. Peritoneal dialysis utilizes the lining of the abdomen, called the peritoneal membrane, as a natural filter to clean the blood. It involves introducing dialysis fluid into the peritoneal cavity, where it absorbs waste products and is then drained away.

Identifying the Correct Statement

Based on the description of peritoneal dialysis, we can determine whether blood is removed from the body and the type of filter used. Peritoneal dialysis does not require the removal of blood from the body since the peritoneal membrane within the body acts as a natural filter.

Elimination Process

Since peritoneal dialysis does not involve removing blood from the body, any option stating otherwise can be eliminated. Also, since it utilizes the body's natural membrane rather than an artificial filter, options suggesting an artificial filter can be disregarded. Hence, we are left with the correct answer.

Key concepts

Kidney Failure Treatment

Kidney failure, also known as renal failure, occurs when the kidneys can no longer adequately filter waste products from the blood. Treatment options vary depending on the severity of the condition. For end-stage renal disease (ESRD), the primary treatments are dialysis or a kidney transplant.

Peritoneal dialysis (PD) is one popular method of dialysis that allows individuals to carry out the treatment at home. It involves cycling a special fluid through the peritoneal cavity, which uses the natural peritoneal membrane as a filter. Unlike hemodialysis, which requires a machine to filter blood outside the body, PD is a continuous process that mimics the natural function of the kidneys more closely. Patients opting for PD must follow a strict schedule and maintain a high level of hygiene to prevent infections.

Peritoneal Membrane

The peritoneal membrane is a semipermeable lining that covers and supports the organs within the abdominal cavity. It plays a crucial role in peritoneal dialysis, acting as a natural filter to replace the function of damaged kidneys. During the PD process, a special solution called dialysis fluid is infused into the peritoneal cavity through a catheter.

The anatomy of the peritoneal membrane, with its complex network of blood vessels, allows for the exchange of waste products and excess fluid from the blood into the dialysis fluid. Over time, the dialysis fluid absorbs the impurities and is later drained from the body, thereby cleansing the blood while avoiding the complete removal of blood from the body, an integral aspect that distinguishes PD from other forms of dialysis.

Dialysis Fluid

Dialysis fluid, also known as dialysate, is a crucial component of peritoneal dialysis. It's a sterile solution composed mainly of water, electrolytes, and salts like sodium chloride and glucose, designed to draw waste products and excess fluid out of the blood.

The process also relies on the principle of osmosis, facilitated by the high glucose concentration in the dialysis fluid, to remove excess water. The composition of the fluid typically matches the needs of the patient, tailored to achieve fluid and electrolyte balance, with some variations possible to meet specific medical requirements. Proper management of the dialysis fluid is essential as it can impact the effectiveness of the PD treatment and the patient’s overall health.

Waste Removal from Blood

The primary function of the kidneys is to filter and clean the blood, removing waste products and excess water to form urine. When kidneys fail, this process is compromised, leading to the accumulation of harmful substances like urea and creatinine, as well as an imbalance of electrolytes.

In peritoneal dialysis, the waste removal from blood is facilitated by the peritoneal membrane, which allows for the transfer of these wastes and excess fluids to the dialysis fluid. During this exchange, a gradient is created across the membrane, and because of the principle of diffusion, waste products naturally move from an area of higher concentration in the blood to the lower concentration in the dialysis fluid. This is how PD helps to cleanse the blood in patients with kidney failure, in a continuous, home-based treatment that serves as a lifeline for those affected by this condition.