Intraperitoneal surgery encompasses a range of medical procedures performed within the peritoneal cavity, a space located inside the abdomen. These surgical interventions address various health concerns, from advanced cancer treatments to diagnostic evaluations following traumatic injuries.
The Peritoneal Cavity
The peritoneal cavity is a potential space situated within the abdominopelvic cavity, bounded by the diaphragm superiorly and the pelvic floor inferiorly. This cavity is lined by a serous membrane called the peritoneum, which consists of two layers: the parietal peritoneum lining the abdominal walls and the visceral peritoneum enveloping many abdominal organs. Between these layers, a small amount of lubricating serous fluid is present, enabling organs to move smoothly against each other with minimal friction.
Several vital organs are located within this space, including the stomach, spleen, liver, parts of the duodenum, jejunum, ileum, and sections of the large intestine like the transverse and sigmoid colon. The peritoneum also forms folds and double layers, such as the omentum and mesentery, which help support and protect these organs while providing pathways for blood vessels, nerves, and lymphatic drainage.
Hyperthermic Intraperitoneal Chemotherapy (HIPEC)
Hyperthermic Intraperitoneal Chemotherapy (HIPEC) is a specialized, two-step surgical procedure primarily used to treat advanced abdominal cancers that have spread to the peritoneal lining. This technique combines extensive surgical removal of visible tumors with the direct application of heated chemotherapy drugs within the abdominal cavity. It offers a targeted approach for cancers that are difficult to treat with traditional systemic chemotherapy.
The first step is cytoreductive surgery, where a surgeon makes an incision to identify and remove all visible cancerous tumors and diseased tissue. This process aims to leave behind as few cancer cells as possible, as even microscopic cells can lead to recurrence. The extent of this removal depends on how widely the cancer has spread within the abdominal cavity.
Following the cytoreductive surgery, the second step involves the HIPEC procedure itself. Heated chemotherapy drugs are directly administered into the abdominal cavity through catheters connected to a perfusion machine. The chemotherapy solution is warmed to a temperature of approximately 41-42 degrees Celsius (around 106-108 degrees Fahrenheit) and circulated within the abdomen for about 90 minutes to two hours. This elevated temperature enhances the drug’s ability to penetrate and destroy remaining microscopic cancer cells.
This direct and heated delivery allows for a significantly higher concentration of chemotherapy to reach the cancer cells within the peritoneal cavity compared to traditional intravenous chemotherapy, which circulates throughout the entire body. By keeping the drug localized, HIPEC can reduce systemic side effects. Cancers commonly treated with HIPEC include those originating from the appendix, colon, rectum, stomach, ovaries, and peritoneal mesothelioma and primary peritoneal cancer.
Additional Intraperitoneal Procedures
Other intraperitoneal procedures serve various diagnostic and therapeutic purposes within the abdominal cavity. These interventions also involve accessing the peritoneal space, though their objectives differ significantly from complex cancer treatment. They include paracentesis and diagnostic peritoneal lavage (DPL).
Paracentesis is a procedure primarily used to remove fluid buildup in the abdomen, a condition known as ascites. This fluid accumulation can cause discomfort, swelling, and breathing difficulties. A healthcare provider inserts a hollow needle or catheter through the skin and muscles into the abdominal cavity to drain the fluid. Paracentesis can be performed to relieve symptoms or to collect fluid samples for analysis, helping to diagnose the underlying cause of the ascites, such as infection, inflammation, or the presence of cancerous cells.
Diagnostic peritoneal lavage (DPL) is another intraperitoneal procedure, often employed in emergency settings to evaluate traumatic injuries, particularly when there is suspicion of internal bleeding or organ damage in the abdomen. The procedure involves making a small incision, inserting a catheter into the peritoneal cavity, and attempting to aspirate any free fluid, typically blood. If no significant amount of blood is aspirated, a warm saline solution, usually one liter of 0.9% saline, is infused into the cavity for a few minutes and then drained for laboratory analysis. The analysis of the retrieved fluid helps determine if an intra-abdominal injury requiring surgical exploration, known as a laparotomy, has occurred.