Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ INTRODUCTION ++ Nausea is usually defined as the inclination to vomit or as a feeling in the throat or epigastric region alerting an individual that vomiting is imminent. Vomiting is defined as the ejection or expulsion of gastric contents through the mouth, often requiring a forceful event. +++ ETIOLOGY AND PATHOPHYSIOLOGY ++ Specific etiologies associated with nausea and vomiting are presented in Table 27–1. Table 27–2 presents cytotoxic agents categorized by their emetogenic potential. Although some agents may have greater emetogenic potential than others, combinations of agents, high doses, clinical settings, psychological conditions, prior treatment experiences, and unusual stimuli to sight, smell, or taste may alter a patient’s response to a drug treatment. The three consecutive phases of emesis are nausea, retching, and vomiting. Nausea, the imminent need to vomit, is associated with gastric stasis. Retching is the labored movement of abdominal and thoracic muscles before vomiting. The final phase of emesis is vomiting, the forceful expulsion of gastric contents due to GI retroperistalsis. Vomiting is triggered by afferent impulses to the vomiting center, a nucleus of cells in the medulla. Impulses are received from sensory centers, such as the chemoreceptor trigger zone (CTZ), cerebral cortex, and visceral afferents from the pharynx and GI tract. When excited, afferent impulses are integrated by the vomiting center, resulting in efferent impulses to the salivation center, respiratory center, and the pharyngeal, gastrointestinal (GI), and abdominal muscles, leading to vomiting. ++Table Graphic Jump LocationTABLE 27–1Specific Etiologies of Nausea and VomitingView Table||Download (.pdf) TABLE 27–1 Specific Etiologies of Nausea and Vomiting GI mechanisms Mechanical obstruction Gastric outlet obstruction Small bowel obstruction Functional GI disorders Gastroparesis Nonulcer dyspepsia Chronic intestinal pseudoobstruction Irritable bowel syndrome Organic GI disorders Peptic ulcer disease Pancreatitis Pyelonephritis Cholecystitis Cholangitis Hepatitis Acute gastroenteritis Viral Bacterial Cardiovascular diseases Acute myocardial infarction Congestive heart failure Radio-frequency ablation Neurologic processes Increased intracranial pressure Migraine headache Vestibular disorders Metabolic disorders Diabetes mellitus (diabetic ketoacidosis) Addison’s disease Renal disease (uremia) Psychiatric causes Psychogenic vomiting Anxiety disorders Anorexia nervosa Therapy-induced causes Cytotoxic chemotherapy Radiation therapy Theophylline preparations Anticonvulsant preparations Digitalis preparations Opiates Antibiotics Volatile general anesthetics Drug withdrawal Opiates Benzodiazepines Miscellaneous causes Pregnancy Noxious odors Operative procedures ++Table Graphic Jump LocationTABLE 27–2Emetic Risk of Agents Used in OncologyView Table||Download (.pdf) TABLE 27–2 Emetic Risk of Agents Used in Oncology Emetic Risk (If No Prophylactic Medication Is Administered) Cytotoxic Agent (in Alphabetical Order) High (>90%) Combination of either doxorubicin or epirubicin + cyclophosphamide Carmustine Cisplatin (>50 mg/m2) Cyclophosphamide (≥1500 mg/m2) Dacarbazine Ifosfamide (>10 g/m2) Mechlorethamine Streptozotocin Moderate (30%–90%) Aldesleukin (>12–15 million units/m2) Amifostine (>300 mg/m2) Arsenic trioxide Azacitidine Bendamustine Busulfan Carboplatin Cisplatin (<50 mg/m2) Clofarabine Cytarabine (>200 mg/m2) Cyclophosphamide (<1500 mg/m2) Daunorubicin Dactinomycin Doxorubicin Epirubicin Idarubicin Ifosfamide Interferon alfa (10 million units/m2... Your MyAccess profile is currently affiliated with '[InstitutionA]' and is in the process of switching affiliations to '[InstitutionB]'. Please click ‘Continue’ to continue the affiliation switch, otherwise click ‘Cancel’ to cancel signing in. Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth