Hyperthermic cytostatic lavage

Hyperthermic cytostatic lavage of the abdominal cavity is a new technique for the treatment of patients during and after surgery. Being originally developed for malignant tumors of the peritoneum, this technique is currently also applied with good results during other challenging surgical procedures. Liberation of cells occurs during the surgical procedure, usually when removing the tumor, and these cells can adhere to wound surfaces and grow subsequently. In addition, only visible structures can be removed during surgery, while the microscopic ones remain undetected. To avoid their new growth, any tumor residues must be removed as soon as possible. A novel technique of abdominal lavage known as “Hyperthermic cytostatic intraoperative intraperitoneal lavage of the abdominal cavity” according to Prof. Sugarbaker is the most effective of the currently available methods for their elimination.

The principle of the lavage consists of filling the patient’s abdominal cavity with a cytostatic solution and keeping the temperature of this solution at around 43°C. This process incorporates two important principles that are required to eliminate small tumor cells, thermotoxicity and cytotoxicity and their combinations resulting in a multiplying effect. The principle of thermotoxicity is elimination of tumor cells caused by high temperatures of the solution. Being generally poorly supplied with blood, the tumor tissue is unable to carry the heat away and covers its surface with a protective protein layer to avoid heat elimination (unlike healthy tissue which can conduct heat due to a good blood supply). The protein layer however makes the tumor tissue identifiable for the immune system, which can recognize it as an intruder and fight against it effectively. (Until being exposed to the said temperature). Cytotoxicity is based on the elimination of tumor cells by the cytostatic solution if present in concentrations above threshold values. Concentrations of cytostatic agents used during the lavage are up to 1000 higher than those used in traditional intravenous outpatient application. The combined effect of thermotoxicity and cytotoxicity makes the cytostatic solution reach all parts of the human body in suprathreshold concentrations (including the finest blood vessels and capillaries in the brain), where it should kill tumor cells earlier, before they become immune to the cytostatic solution. This time period is critical and ranges from 30 to 35 minutes after the application of the cytostatic solution. Given the natural thermoregulation of the human body, the cytostatic solution is cooled in the abdominal cavity and must be re-circulated. During the recirculation it is filtrated and heated to a temperature close to 43°C. Based on practical experience, the effective period of action of the heated cytostatic solution has been determined to be 90 minutes. (More informations on www.surgicaloncology.com or www.peritonectomy.com)

The lavage device ensures a sterile recirculation of the solution at a required flow rate, temperature control of the circulated solution in the abdominal cavity at around 43°C, and filtration of the solution from blood clots or other small particles of fat or other tissues. The safety of the system is assured by monitoring the individual parameters using independent measuring systems.

Special sterile lavage sets are hermetically interconnected to ensure recirculation of the cytostatic solution from the device into the patient and back.

Odstranění rizika kontaminace HIV / AIDS

FDA varování: http://www.fda.gov/cdrh/safety/althin.html

Healthcare personnel coming into contact with HIV positive patients or patients positive for hepatitis B, hepatitis C, and so on, should be aware of this. According to the condition of the patient, they should perform all the) available measures during the admission, treatment and inpatient stay of the patient to ensure high-quality treatment and to avoid any risk to the health or lives of other patients or even the personnel. As we know from practical experience, however, there is no space for any delay in emergency situations and the personnel learns no information about the actual condition of the patient until blood or tissue analyses are ready, which is usually a long time after the series of difficult, life-saving interventions and operations have been performed (for example a car accident involving a HIV/AIDS-positive patient). As a result, the device often becomes contaminated by virulent patients, thus posing a risk of contamination of other patients. The device becomes hazardous for other patients and personnel.

To minimize such risk, the US FDA recommends a series of measures, which pertain to increased caution on the part of healthcare personnel during interactions with patients, and increased caution when identifying infectious and non-infectious devices. However, this may not be enough in practice, as documented by the constantly increasing percentage share of patients who have become infected from the device during treatment. In some dialysis centers in the USA, prevalence of HIV kazeta infection in patients after 5 years of dialysis treatment increased approximately 2 500 times compared to the general population (from the average 0.016% in the general population to approximately 40% of treated patients).

To substantially reduce or eliminate this risk, our firm developed a special pressure cassette for pressure measurement and analysis, which prevents the device-related transmission of blood-borne infections, despite using the device in more patients. The principle of safe operation in an unknown infected patient is that the potential infection does not affect the device itself but only the replaceable pressure cassette, which can be easily gas sterilized or is intended for temporary use in a single patient (or for single use). Other patients receiving treatment with the same device are protected against blood contamination due to the "individualization" of the cassettes and direct measurement of the blood pressure by the device.

Although the overall impact on the health and lives of the patients cannot be exactly quantified, we can estimate that health insurers will save substantial amounts on the treatment of known diseases, such as hepatitis B, C,….or HIV/AIDS, as well as other diseases occurring in dynamically developing civilizations. Not to mention the lifelong complications suffered by patients who have experienced blood-borne infection.