pathophysiology of nausea and vomiting pdf

Pathophysiology Of Nausea And Vomiting Pdf

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Chemotherapy-induced nausea and vomiting: pathophysiology and therapeutic principles

One of the side effects of radiation therapy is radiation-induced emesis; however, antiemetics appear to sometimes be underutilized. Several organizations have published guidelines on the management of radiation-induced nausea and vomiting based on the level of risk. Appropriate prevention and treatment of radiation-induced nausea and vomiting are necessary for completing the course of radiation therapy so that a positive treatment outcome may be achieved without interruption.

Radiation-induced nausea and vomiting as a side effect of radiation therapy may be underestimated by both the heathcare provider and the patient. Patients undergoing this therapy often receive up to 40 fractions of radiation in a 6- to 8-week period. Patients with radiation-induced nausea and vomiting potentially could refuse further treatment or experience delays in treatment, which could adversely affect outcome. The severity of nausea and vomiting induced by radiation therapy depends mainly on the area where the radiation is delivered.

Total-body radiation has the highest likelihood of inducing nausea and vomiting, and radiation delivered to the upper abdomen incurs the second-highest risk. Also, increasing the body area being irradiated, the radiation fractions used, and the overall total dose of radiation administered will elevate the risk of radiation-induced nausea and vomiting.

The pathophysiology and mechanisms of radiation-induced emesis are complex. It has been suggested that both serotonin levels and the abdomen play important roles in radiation-induced nausea and vomiting. Elevated levels of the active serotonin metabolite 5-hydroxyindoleacetic acid have been identified in the urine of patients experiencing this side effect.

Also, emesis caused by radiation therapy can be well controlled with administration of a 5-hydroxytryptamine type 3 5-HT 3 receptor antagonist, which confirms the role of serotonin in radiation-induced nausea and vomiting. Statistically significant factors that influence the prescribing of antiemetic therapies are concurrent administration of chemotherapy with radiation therapy and previous occurrence of chemotherapy-induced vomiting.

Based on study results, radiation-induced nausea and vomiting appear to be underestimated, and antiemetics for the condition are being underprescribed by radiation oncologists. A variety of antiemetic agents have been used for the prevention and treatment of radiation-induced nausea and vomiting, but the most evidence is available for 5-HT 3 receptor antagonists.

In patients receiving radiation to the upper abdomen or other localized sites, either granisetron 2 mg by mouth daily or ondansetron 8 mg by mouth twice daily, with or without dexamethasone 4 mg by mouth daily, should be given. For concurrent administration of chemotherapy and radiation, it is recommended that an antiemetic regimen appropriate for chemotherapy be used. Some chemotherapy agents confer a higher emetogenic risk when they are combined with radiation. Patients who experience breakthrough radiation-induced nausea and vomiting should be given a drug of a different class from the agent administered for breakthrough chemotherapy-induced nausea and vomiting.

Patients who experience breakthrough radiation-induced nausea and vomiting should be given a drug of a different class from the agent administered for prophylaxis of the nausea and vomiting. It is recommended that patients who are undergoing high-risk total-body radiation be offered a two-drug regimen for prevention of radiation-induced nausea and vomiting.

The two-drug regimen should comprise either ondansetron oral, oral dissolving tablet, oral soluble film, or IV or granisetron oral or IV plus oral or IV dexamethasone. Ondansetron may be administered once or twice daily on radiation-therapy days; if it is administered twice daily, the first dose should be administered prior to the radiation. Also, the patient should receive ondansetron once or twice daily on the day following each radiation session if radiation therapy is not planned for that day.

Granisetron is administered once daily on the day of each radiation session prior to administration of radiation and on the day after each radiation session if radiation therapy is not planned for that day.

Dexamethasone is administered prophylactically once daily on days of radiation therapy before radiation is administered and on the day following each radiation session if radiation therapy is not planned for that day.

Patients receiving moderate-risk radiation upper abdominal or craniospinal should be given prophylactic treatment with ondansetron oral, oral dissolving tablet, oral soluble film, or IV , granisetron oral or IV , or tropisetron oral or IV and, optionally, oral or IV dexamethasone. Prophylactic ondansetron may be administered once or twice daily on days of radiation therapy, with the first dose administered before the radiation.

Granisetron and tropisetron are administered once daily before the radiation. If dexamethasone is used prophylactically, it should be administered once daily prior to the radiation on the first 5 days of radiation therapy. According to the ASCO, patients undergoing low-risk radiation head and neck, thorax, or pelvis or minimal-risk radiation extremities or breast should be offered rescue therapy with ondansetron or granisetron, dexamethasone, or a dopamine receptor antagonist prochlorperazine or metoclopramide.

Patients undergoing low-risk radiation to the brain should be offered dexamethasone as rescue therapy. Dexamethasone may be administered as a rescue agent if the patient is not already taking a corticosteroid, and the dexamethasone dose should be titrated as needed to a maximum of 16 mg daily oral or IV. Prochlorperazine and metoclopramide administered as rescue agents for low-risk radiation-induced nausea and vomiting should be titrated up as needed to a maximum of 3 to 4 administrations daily.

For adult patients being treated with radiation therapy and chemotherapy concurrently, the antiemetic regimen should be appropriate for the emetic risk of chemotherapy if the risk level of radiation therapy is not higher than the risk level of chemotherapy. If radiation therapy continues after chemotherapy has been completed, the antiemetic regimen should be adjusted to the emetic risk of radiation therapy.

The high-risk category comprises total-body radiation; it is recommended that these patients receive prophylactic treatment with 5-HT 3 receptor antagonists in combination with dexamethasone. Patients undergoing upper-abdominal or craniospinal radiation therapy are considered to be at moderate risk for developing radiation-induced nausea and vomiting. In these patients, prophylactic treatment with a 5-HT 3 receptor antagonist and optional dexamethasone is recommended.

Patients receiving radiation to the cranium, head and neck, thorax region, or pelvis are considered to have a low risk of developing radiation-induced nausea and vomiting. Patients receiving cranial radiation should be given dexamethasone as prophylactic or rescue therapy. Those receiving radiation therapy to the head and neck, thorax region, or pelvis should receive prophylactic or rescue therapy with dexamethasone, a dopamine receptor antagonist, or a 5-HT 3 receptor antagonist.

Patients who receive minimal-risk radiation therapy extremities or breast should be offered rescue therapy with dexamethasone, a dopamine receptor antagonist, or a 5-HT 3 receptor antagonist. If a patient receives concomitant chemotherapy and radiation therapy, the antiemetic therapy should be aligned with the emetic risk of the chemotherapy unless radiation therapy has a higher risk of inducing nausea and vomiting.

Therefore, prevention and treatment are important to help avoid or alleviate the symptoms of radiation-induced nausea and vomiting. Support Care Cancer. Urba S.

Radiation-induced nausea and vomiting. J Natl Compr Canc Netw. A prospective observational trial on emesis in radiotherapy: analysis of patients recruited in 45 Italian radiation oncology centres. Radiother Oncol. On the mechanism of radiation-induced emesis: the role of serotonin. A randomised placebo controlled study with ondansetron in patients undergoing fractionated radiotherapy. Ann Oncol. Double-blind, randomized, parallel-group study on the efficacy and safety of oral granisetron and oral ondansetron in the prophylaxis of nausea and vomiting in patients receiving hyperfractionated total body irradiation.

Bone Marrow Transplant. National Comprehensive Cancer Network. Version 1. Accessed August 15, J Clin Oncol. Featured Issue Featured Supplements. US Pharm. To comment on this article, contact rdavidson uspharmacist. Related CE.

View More CE. Related Content. All rights reserved. Reproduction in whole or in part without permission is prohibited.

Overview of Chemotherapy-Induced Nausea and Vomiting and Evidence-Based Therapies

Vomiting is the forceful expulsion of contents of the stomach and often, the proximal small intestine. It is a manifestation of a large number of conditions, many of which are not primary disorders of the gastrointestinal tract. Regardless of cause, vomiting can have serious consequences, including acid-base derangments, volume and electrolyte depletion, malnutrition and aspiration pneumonia. Vomiting is usually experienced as the finale in a series of three events, which everyone reading this has experienced:. The series of events described seems to be typical for humans and many animals, but is not inevitable. Vomition occasionally occurs abruptly and in the absense of premonitory signs - this situation is often referred to as projectile vomiting.

Nausea has been considered a uniquely unpleasant discomfort that defies precise definition 1. Although this statement may be reasonably accurate, it has little clinical utility. Retching consists of spasmodic inspiratory movements with the glottis closed and abdominal muscle contractions such that the pressure generated by the abdominal musculature is opposed by negative intrathoracic pressure the gastric antrum contracts - while fundus and cardiac relax. Vomiting is the forceful expulsion of the gastric contents out of the mouth from a coordinated contraction of predominantly abdominal muscles and diaphragm while the gastric cardia is open and elevated with contracted pylorous 2. Nausea may be accompanied by autonomic-driven physiologic changes of pallor, diaphoresis, altered heart rate tachycardia or bradycardia , upper GI tract hypersecretion, and relaxation of the gastric fundus and cardia 2. It is important to document the perceived level of nausea intensity.


Stimuli giving rise to nausea and vomiting originate from visceral, vestibular, and chemoreceptor trigger zone inputs which are mediated by serotonin/dopamine.


Management of Radiation-Induced Nausea and Vomiting

Vomiting also known as puking , throwing up , barfing , emesis , among other names is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be caused by many conditions; it may be present as a specific response to ailments like gastritis [2] or poisoning , or as a non-specific sequela ranging from brain tumors and elevated intracranial pressure to overexposure to ionizing radiation. The feeling that one is about to vomit is called nausea ; it often precedes, but does not always lead to vomiting. Antiemetics are sometimes necessary to suppress nausea and vomiting. In severe cases, where dehydration develops, intravenous fluid may be required.

Vomiting can also be referred to as emesis , and consists of the following stages: Nausea Nausea is an unpleasant sensation of wanting to vomit , and is often associated with cold sweat, pallor , salivation, loss of gastric tone, duodenal contraction, and the reflux of intestinal contents into the stomach. Nausea generally precedes vomiting, but can occur by itself. The system that brings about the loss of gastric tone, of gastric relaxation, is the efferent part of the long loop intestinal reflex that relaxes the gut during food intake. Retching Retching is a strong involuntary effort to vomit , and usually follows nausea.

Overview of Chemotherapy-Induced Nausea and Vomiting and Evidence-Based Therapies

Pathophysiology of nausea and vomiting in palliative medicine

Chemotherapy-induced nausea and vomiting CINV is a major determinant of quality of life in cancer patients. In addition, the perceptions that oncology professionals have about CINV quite often do not coincide with reality. Antineoplastic agents and their combinations can be categorised according to their emetogenic level, and this categorisation is helpful for classifying the severity of CINV and treating it. All CINV treatment guidelines emphasise the need to administer prophylaxis to patients who receive highly or moderately emetogenic chemotherapy.

One of the side effects of radiation therapy is radiation-induced emesis; however, antiemetics appear to sometimes be underutilized. Several organizations have published guidelines on the management of radiation-induced nausea and vomiting based on the level of risk. Appropriate prevention and treatment of radiation-induced nausea and vomiting are necessary for completing the course of radiation therapy so that a positive treatment outcome may be achieved without interruption.

References

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