What Do the Kidneys Do? (7 Functions)
What do the kidneys do? (7 functions) The kidneys are more than just “urine-making machines.” They are sophisticated, life-sustaining chemical factories that work 24/7 to keep your blood c...

The term peritoneum stems from the Greek peritonaion, meaning “to stretch around.”
1550 BC: The Ebers Papyrus contains the first recorded reference to the peritoneal cavity.
Antiquity: Ancient Egyptians identified the membrane during mummification. Later, the Roman physician Galen observed the peritoneum while treating injured gladiators.
1914: While the word dialysis (Greek for “separation”) dates back to the 1500s, it was first applied to medical contexts in the early 20th century.
Before PD became a clinical reality, scientists had to understand the membrane’s physiological properties.
1740s: Surgeon Christopher Warrick attempted a primitive infusion of wine and water into the peritoneum to treat ascites. Surprisingly, the patient recovered.
1877: G. Wegner established the basis for peritoneal ultrafiltration by showing that concentrated sugar solutions could pull fluid into the abdominal cavity.
1894: Starling and Tubby demonstrated the bidirectional transfer of molecules across the membrane.
1922: Putnam confirmed that mass transfer was driven by passive concentration gradients, setting the stage for human trials.
The mid-20th century saw the transition from laboratory experiments to bedside therapy.
1923: George Ganter performed the first successful human peritoneal dialysis for “uraemia.”
1938: Rhoads introduced Intermittent Peritoneal Dialysis (IPD) and added lactate as a buffer—a standard still used in many modern PD fluids.
1951: Arthur Grollman developed a flexible polyethylene catheter, significantly improving fluid flow and patient comfort.
1959: Morton Maxwell standardized the “Maxwell Technique,” a simplified gravity-based system that made PD accessible to hospitals without specialised equipment.
Technological breakthroughs eventually moved treatment from the hospital to the patient’s home.
1967 (Tenckhoff Catheter): Henry Tenckhoff refined a silicone permanent indwelling tube. This remains the global gold standard for permanent peritoneal access.
1976 (CAPD): Popovich and Moncrief introduced Continuous Ambulatory Peritoneal Dialysis, allowing patients to remain mobile while dialysing.
1981 (The Y-System): Umberto Buoncristiani developed the “flush before fill” connector, which drastically reduced peritonitis (infection) rates.
1987 (Standardisation): Twardowski created the Peritoneal Equilibration Test (PET) to quantify how efficiently an individual’s membrane transports solutes.
Focus shifted from hardware to biocompatibility and digital integration.
1990s (Automation): The widespread adoption of Automated Peritoneal Dialysis (APD) “cyclers” allowed patients to dialyse while sleeping.
1996 (Icodextrin): Introduction of glucose-free osmotic agents allowed for better fluid removal without metabolic damage.
Late 1990s (Multi-Chamber Bags): Neutral pH and low Glucose Degradation Products (GDPs) helped preserve the peritoneal membrane for longer years.
2015 (Remote Management): Cloud-based platforms allowed clinicians to monitor treatment data and adjust prescriptions remotely.
2023–2026 (Wearables): Clinical trials for the Automated Wearable Artificial Kidney (AWAK) aim to make PD truly portable by recycling dialysate through sorbent technology.
| Era | Milestone | Impact |
| 1877 | Wegner’s Experiments | Discovery of osmotic ultrafiltration. |
| 1923 | Ganter’s Human Trial | Proven treatment for uremia (CKD). |
| 1959 | Maxwell Technique | Simplified, sterile bedside dialysis. |
| 1967 | Tenckhoff Catheter | Reliable, long-term peritoneal access. |
| 1976 | CAPD Introduction | Enabled home-based, mobile therapy. |
| 1981 | Y-Connector System | Major breakthrough in infection control. |
| 1987 | PET Test | Standardised measurement of membrane efficiency. |
| 1996 | Icodextrin | Improved fluid removal without sugar toxicity. |
| 2000s | Biocompatible Solutions | Preserved the “life” of the membrane via neutral pH. |
| 2015 | Cloud Remote Monitoring | Enabled “telemedicine” for home dialysis safety. |
| 2023+ | Wearable/Sorbent Tech | The push toward portable, water-efficient units. |
From ancient scrolls to smartphone-integrated cyclers, the history of PD is defined by the quest for simpler, safer, and more autonomous patient care. Today, the focus is on “Incremental PD,” tailoring therapy to a patient’s remaining kidney function to maximize their quality of life.
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