tailieunhanh - Chapter 081. Principles of Cancer Treatment (Part 22)

Nausea and Vomiting The most common side effect of chemotherapy administration is nausea, with or without vomiting. Nausea may be acute (within 24 h of chemotherapy), delayed (24 h), or anticipatory of the receipt of chemotherapy. Patients may be likewise stratified for their risk of susceptibility to nausea and vomiting, with increased risk in young, female, heavily pretreated patients without a history of alcohol or drug use but with a history of motion or morning sickness. Antineoplastic agents vary in their capacity to cause nausea and vomiting. . | Chapter 081. Principles of Cancer Treatment Part 22 Nausea and Vomiting The most common side effect of chemotherapy administration is nausea with or without vomiting. Nausea may be acute within 24 h of chemotherapy delayed 24 h or anticipatory of the receipt of chemotherapy. Patients may be likewise stratified for their risk of susceptibility to nausea and vomiting with increased risk in young female heavily pretreated patients without a history of alcohol or drug use but with a history of motion or morning sickness. Antineoplastic agents vary in their capacity to cause nausea and vomiting. Highly emetogenic drugs 90 include mechlorethamine streptozotocin DTIC cyclophosphamide at 1500 mg m2 and cisplatin moderately emetogenic drugs 30-90 risk include carboplatin cytosine arabinoside 1 mg m2 ifosfamide conventional-dose cyclophosphamide and anthracyclines low-risk 10-30 agents include fluorouracil taxanes etoposide and bortezomib with minimal risk 10 afforded by treatment with antibodies bleomycin busulfan fludarabine and vinca alkaloids. Emesis is a reflex caused by stimulation of the vomiting center in the medulla. Input to the vomiting center comes from the chemoreceptor trigger zone CTZ and afferents from the peripheral gastrointestinal tract cerebral cortex and heart. The different emesis syndromes require distinct management approaches. In addition a conditioned reflex may contribute to anticipatory nausea arising after repeated cycles of chemotherapy. Accordingly antiemesis agents differ in their locus and timing of action. Combining agents from different classes or the sequential use of different classes of agent is the cornerstone of successful management of chemotherapy-induced nausea and vomiting. Of great importance are the prophylactic administration of agents and such psychological techniques as the maintenance of a supportive milieu counseling and relaxation to augment the action of antiemetic agents. Serotonin antagonists 5HT3 and neurokine NK1 .