nausea & vomiting final

7/31/2019 Nausea & Vomiting FINAL

http://slidepdf.com/reader/full/nausea-vomiting-final 1/25



Introduction

Nausea is an uneasy or unsettled feeling in the stomachtogether with an urge to vomit. Nausea and vomiting, orthrowing up, are not diseases.

They can be symptoms of many different conditions.These include :

morning sickness during pregnancy,

infections,

migraine headaches,

motion sickness,

food poisoning,

cancer chemotherapy or other medicines.

others

2



Introduction

Nausea and vomiting are common. Usually, they arenot serious.

BUT IF the following cases occur immediatereferral is recommended

Vomited for longer than 24 hours

Blood in the vomit

Severe abdominal pain

Headache and stiff neck

3



Pathophysiology

Nausea and vomiting consist of three stages:

1. Nausea, : nausea is the subjective feeling of a need to vomit. It is oftenaccompanied by autonomic symptoms such as pallor, tachycardia,diaphoresis, and salivation

2. Retching, which follows nausea, consists of diaphragm, abdominal wall, andchest wall contractions and spasmodic breathing against a closed glottis.

Retching can occur without vomiting, but this stage produces the pressuregradient needed for vomiting, although no gastric contents are expelled.

3. Vomiting, or emesis, is a reflexive, rapid, and forceful oral expulsion of upper gastrointestinal contents due to powerful and sustained contractions inthe abdominal and thoracic musculature.1 Vomiting, like nausea, can beaccompanied by autonomic symptoms.

note :

Regurgitation, unlike vomiting, is a passive process without involvement of theabdominal wall and diaphragm wherein gastric or esophageal contents move intothe mouth. in patients with gastro esophageal reflux disease (GERD), onehallmark symptom is acid regurgitation.4



Pathophysiology

Various areas in the brain and thegastrointestinal (GI) tract are stimulatedwhen the body is exposed to noxiousstimuli (e.g., toxins), gastro-intestinalirritants (e.g., infectious agents), orchemotherapy.

These areas include : the chemoreceptor trigger zone (CTZ) in the

area postrema of the fourth ventricle of the

brain,(outside BBB-???) serotonin type 3(5-HT3), neurokinin-1 (NK1), anddopamine (D2) receptors.

the vestibular system (H1,M)

visceral afferents from the GI tract (5-HT3 R ),

the cerebral cortex .

5



6

Chemoreceptor trigger zone (CTZ)(5-ht3, D2, NK!)

Gastrointestinal visceralafferents

(5ht3, D2, NK1)

Cerebral cortex(sensory input )

Vestibular system(H1, Muscarinic) Central

vomitingcenters

(medulla)

Stimulation of salivation & respiratory

centers,pharyngeal ,

GI, Abdominalmuscle

contraction

Nauseavomitin

Physiologic pathways that result in nausea and vomiting. 5-HT3, serotonin type 3 receptor; D2,dopamine type 2 receptor; GI, gastrointestinal; H1, histamine type 1 receptor, NK1, neurokinin-1.(Adapted from American Society of Health-System Pharmacists. ASHP therapeutic guidelines on the

pharmacologic management of nausea and vomiting in adult and pediatric patients receivingchemotherapy or radiation therapy or undergoing surgery

CTH,TOXINS

Motion,

CTH,INFECTIONS

Emotionalcauses



Pathophysiology

Motion sickness is caused by stimulation of the vestibular system. Thisarea contains many histaminic (H1) and muscarinic cholinergicreceptors.

The higher brain (i.e., cerebral cortex) is affected by sensory inputsuch as sights, smells, or emotions that can lead to vomiting. This areais involved in anticipatory nausea and vomiting associated withchemotherapy.

Nausea and vomiting can be classified as either simple or complex.

Simple nausea and vomiting occurs occasionally and is either self-limiting or relieved by minimal therapy. It does not have detrimentaleffects on hydration status, electrolyte balance, or weight because it isshort-lived.

complex nausea and vomiting requires more aggressive therapy because

electrolyte imbalances, dehydration, and weight loss may occur. Unlikesimple nausea and vomiting, complex nausea and vomiting can becaused by exposure to noxious agents.

7



Rubenstein ED, et al Cancer J 2006

NeuroanatomicalCenters:Emetic centerChemoreceptor trigger zoneVagal afferents of GI

Neurotransmitters:Dopamine (DA)Serotonin (5HT)

Substance P GABA Cannabinoid I Acetylcholine Endorphins

EmeticCenter

CTZ



Assessment & Interpretation

9



Nature & severity

Projectile vomiting :

babies pyloric stenosis ,

Adults with history of peptic ulceration(usually duodenal ).

Sour smelling vomit possible obstruction(e.g. pyloric stenosis)

Blood stained vomit (hematemesis)

Blood may appear:

fresh & bright red, or dark with clotted appearance

If blood originates in the stomach , it will be

degraded by gastric acid producing a dark coloredvomit with a coffee ground appearance

10



Frequent vomiting for more than 24-48hr.

Deteriorating nausea , increasedincidence of vomiting over a longerperiod of time

Sudden vomiting without nausea is acharacteristic of a central cause (e.g.Cerebral tumor or injury),

Nausea preceding vomiting indicates agastrointestinal cause.

11

Onset & duration



Accompanying symptoms

Abdominal pain may cause reflex vomiting as in:

paroxysmal coughing can lead to vomiting .

Other disorders may lead to vomiting include Ménière’s

disease & acute pain in extra abdominal body system(glaucoma)

Gastroenteritis : Diarrhea accompanying vomitingsuggests , usually due to ingestion of some dietary insult orto infection or food

food poisoning : Recent travelers to hot countries shouldbe referred to eliminate dysentery &

12

─ liver disease ─ appendicitis , ─ biliary colic

─ renal colic ─ hernias & ─ genital disorder



Central nervous disorder (e.g. space occupyinglesions, meningitis , head injury & subdural hemorrhage )

Migraine attacks.

Anxiety or an emotional disturbance

anorexia nervosa & bulimia.

Note:

Episodic or chronic vomiting accompanied by weight lossrequires referral for investigation of the cause .

13

Accompanying symptoms



If the cause can be elicited, the decision of whether to refer or not becomes easier

Common dietary cause are hot or spicy foods , over indulgence of food oralcohol , & sensitivity to certain foods (e.g.. Sea food , pork…). such case willusually resolve spontaneous within 24 hrs.

Many drugs can cause nausea & vomiting (e.g. NSAIDS, colchicine , digoxin intoxic doses, Fe , levodopa , theophylline , estrogens & cytotoxic drugs )

Motion is a common cause of N&V, & in severe cases may persist for a day or2 after the journey

Infection may cause vomiting , especially otitis media in children & the earlystages of various viral illness(measles). Condition affecting the abdomen mayresult in reflex vomiting.

Heart failure , particularly right sided HF may result in congestion of theabdominal organs with blood , giving a sensation of nausea & sometimesvomiting.

14

Causative & modifying factors



Episodes of vomiting which may sometimes be severe, inpatients with diabetes , require immediate referral to excludeloss of control of the diabetes.

Chronic alcoholic patients may suffer from early morningvomiting

2 types of vomiting may occur in pregnancy : The familiar syndrome of morning sickness comprises regular bouts of

short lived N or V or both during the 1st few weeks of pregnancy. it mayoccur at any time of the day . It usually resolve spontaneously aroundthe 3rd month of pregnancy . Drugs should not be recommended butreassurance , frequent small meals , rest , and bed rest in the morningare sensible recommendation .

A more sever form of vomiting which may occur in early pregnancy Ishyperemesis gravidarum , it may lead to dehydration & shock & requires medical referral

15

Causative & modifying factors



Risk factors in children

Vomiting in children is usually self remitting butcertain points should be remembered

Many babies regurgitate their milk after meal(posseting) & mothers should be assured thatthis is normal

However , in cases of projectile vomiting (babymay be alert & appear normal OR in babies whoappear distressed, irritable or verydrowsy)referral is required

Children over 2 years of age require referral if they have vomited for more than 24hrs

16



If the cause of vomiting has been identified or issuspected, the underlying disorder should beattended to as a priority

Management :

Non pharmacologic

Pharmacologic

17

Management



Non pharmacologic management

General Measures:

resting the stomach

avoid strong perfumes

evaporation of mint may be helpful

sit in an upright position for 30 - 45 minutes after eating

Avoiding drinking milk or eating heavy or fatty warm, very spicy andodorous meals for 24 hrs.

Sips of tasteless drinks, ideally water, should be taken regularly toprevent dehydration

Food should be avoided until the patients feels hungry (start with breadtoast or plain biscuits )

If tolerated , intake may be increased carefully till a normal diet istolerated

Administration of fluids and electrolytes

18



Acupuncture and acupressure There are indications that acupuncture and/oracupressure (in the form of pressure massage or aspecial wristband) are effective in the case of nauseaand vomiting, particularly after surgery and afterchemotherapy.

Complementary therapies and psychologicaltechniques for psychogenic factors (anxiety and stress) andconditioning (anticipatory nausea and vomiting) playan important role.

These types of nausea and vomiting respond poorly toantiemetics.

These techniques act through relaxation, distraction,and/or a feeling of self-control.

19

Non pharmacologic management

P6 (Neiguan)point



Pharmacologic drug treatment

There are few oral drugs available to treat vomiting attacks

Both antihistamines & anti muscarinic drugs may be usefulto prevent attacks , especially of motion sickness.

Anti histamine such as cinnarizine , diphenhydramine & promethazine which also possess anticholinergic properties, may be useful , but should be used in caution in patients

with glaucoma , prostatitis , constipation & those whodrive.

Note:

Babies and young children should be given oral rehydration

fluid that replace glucose , Na , K lost during vomiting .Glucose enhance the absorption of electrolytes across theinflamed mucosa .

The use of proprietary rehydration fluids in children should beencourage over home remedies to prevent inappropriate load of Na , & K

20



21



Drug Class Information

Antacids

magnesium hydroxide, aluminum hydroxide, and/or calcium carbonate,

relieve N&V, (through gastric acid neutralization.)

Histamine-2 Receptor Antagonists

cimetidine, famotidine, nizatidine, ranitidine N&V associated withheartburn or GERD .

Antihistamine– Anticholinergic Drugs

treatment of simple symptomatology.

Adverse reactions that may be apparent with the use of the antihistaminic– anticholinergic agents primarily include drowsiness or confusion, blurredvision, dry mouth, urinary retention, and possibly tachycardia, particularly inelderly patients.

Phenothiazines “ chlorpromazine , promethazine ”

Phenothiazine are most useful in patients with simple nausea andvomiting.

dangerous side effects, including extrapyramidal reactions, hypersensitivityreactions with possible liver dysfunction, marrow aplasia, and excessivesedation.

22



Metoclopramide

Metoclopramide increases lower esophageal sphincter tone, aids gastricemptying, and accelerates transit through the small bowel, possiblythrough the release of acetylcholine.

Metoclopramide is used for its antiemetic properties in patients withdiabetic gastroparesis and with dexamethasone for prophylaxis of delayednausea and vomiting associated with chemotherapy administration.

Corticosteroids

Dexamethasone has been used successfully in the management of chemotherapy- induced nausea and vomiting (CINV) and postoperativenausea and vomiting (PONV), either as a single agent or in combinationwith selective serotonin reuptake inhibitors (SSRIs). For CINV,dexamethasone is effective in the prevention of both Cisplatin-inducedacute emesis and when used alone or in combination for the prevention of

delayed nausea and vomiting associated with CINV.

23



Selective Serotonin Receptor Inhibitors (Ondansetron, Granisetron,Dolasetron, and Palonosetron)

SSRIs (dolasetron, granisetron, ondansetron, and palonosetron) act by blocking

presynaptic serotonin receptors on sensory vagal fibers in the gut wall.

The most common side effects associated with these agents are constipation, headache,and asthenia

Cannabinoids

When compared with conventional antiemetics, oral nabilone and oral dronabinol wereslightly more effective than active comparators in patients receiving moderately emetogenicchemotherapy regimens.

The efficacy of cannabinoids as compared to SSRIs for CINV has not been studied. Theyshould be considered for the treatment of refractory nausea and vomiting in patientsreceiving chemotherapy.

Substance P/Neurokinin 1 Receptor Antagonists

Substance P is a peptide neurotransmitter in the NK family whose preferred receptor is theNK1 receptor. Substance P is believed to be the primary mediator of the delayed phase of CINV and one of two mediators of the acute phase of CINV.

Aprepitant is the first approved member of this class of drugs and is indicated as part of a

multiple drug regimen for prophylaxis of nausea and vomiting associated with high-dosecisplatin-based chemotherapy.

Numerous potential drug interactions are possible; clinically significant drug interactionswith oral contraceptives, warfarin, and oral dexamethasone have been described.24

nausea & vomiting final

Documents