Digestive tract disorders in palliative care

For the patient, gastrointestinal problems are among the most frequent and cumbersome disorders during palliative care.

They can concern all segments of the digestive tract:

Mouth care,
Dysphagia ,
Dyspepsia,
Hiccups,
Occlusion,
Nausea and vomiting,
Constipation

Mouth care :

During palliative care, patients often suffer from their mouth. This is due to:

mouth dryness or xerostomia,
Treatment related stomatitis (radiotherapy, chemotherapy, antibiotherapy),
very frequent fungal infection,
open mouth breathing,
nutritional imbalance,
loss of autonomy and general weakness (difficult mouth rinsing).

Some very difficult situations are observed in head and neck cancer during the terminal phase.
Poor hygiene often leads to a very foul-smelling breath or halitosis which may increase family uneasiness, speech difficulty and pain during meals associated with difficulty in swallowing.

Prevention of mucitis and the use of simple therapeutic methods are mandatory and should be repeated every day without provoking pain:

The use of Q-tips and compresses to humidify the oral cavity,

Soft tooth-brushing with a pleasant non-irritating tooth paste,

Frequent gargles (when feasible) with Coca-Cola or antifungal mouth rinsing solutions (many magistral preparations exist),

The use of morphinic mouth rinsing solutions when severe, painful mucitis prevents feeding,

Alcoholic solutions should be avoided, since they induce pain when mucitis or mouth ulcers occur.

Good air hydration (use of misty water spray or a nebuliser) also offers improved preservation of oral comfort.

Dysphagia :


Dysphagia can be defined as the difficulty in transferring the alimentary bolus (liquid or solid) from the mouth to the stomach.

In a palliative care unit (like St Christopher), dysphagia is observed in approximately 10% of patients (however, the unit also welcomes patients with lateral sclerosis for which dysphagia is an evolutive phase of the disease).

Deglutition physiology

Four steps are necessary for correct swallowing:

endobuccal preparation of the alimentary bolus (mastication, salivation),

oral swallowing phase, with closed lips and anterior tongue retraction pushing the bolus towards the oropharynx,

pharyngeal phase: partial occlusion of the nasal fossa, complete occlusion of larynx, stopped breathing,

esophageal phase: peristalsis pushes the bolus towards stomach.

The first two phases are voluntary; the latter two are reflexive.

Pathophysiology of deglutition disorders

A tumour mass in the mouth or the superior pharynx will rapidly lead to swallowing difficulties, whereas a low pharynx tumour or an oesophageal tumour will be troublesome only when voluminous.
Treatment of the tumour also provokes major swallowing side-effects:

surgery,radiotherapy: post-radiotherapy sclerosis, mouth dryness, candidiasis,

chemotherapy, not onlyvia chemotherapy alone, but also through the increased risk of candidiasis complicating dry irradiated mucosa,

other potential mouth infections: herpes zoster, cytomegalovirus.

Major problems

Depending of the location, patients may suffer from:

mouth leakage (the patient slavers): lip sensation disorders, abnormal tongue movement, reduced swallowing reflex,

frequent nasal regurgitations poor palatal function (often after surgery or radiotherapy),

swallowing difficulty: the patients pushes his head backwards in order to swallow,

coughing when swallowing may occur

• before deglutition (poor deglutition reflex),
• during deglutition (poor laryngeal occlusion),
• after deglution (difficulty in emptying the pharynx, poor functionning of cricco-pharyngeal muscles, tracheo-esophageal fistula).

Therapeutic attitude

Should enteral alimentation (feeding) or parenteral alimentation (hydration) be proposed to the patient?
The following table summarises enteral and parenteral feeding indications:

General indications	Parenteral route	Nasogastric tube, gastrostomy
Indications Swallowing time greater than 10 seconds No improvement after rehabilitation or nutritional support Radical treatment proposed (surgery, radiotherapy)	Indications Complete pharyngeal or oesophageal obstruction Short use (a few weeks), Other intestinal or gastric problems	Indications Prolonged use (more than two weeks)
Contraindications Rapid terminal deterioration Other major difficulties	Contraindications Presence of sepsis Difficulties at home No access to biochemical monitoring No access to nutritional team Superior vena cava compression	Contraindications For the tube: oesophageal obstruction, fistula For gastrostomy: gastric tumour, occlusion

Some simple advice may help a dysphagic patient to eat normally by mouth:

• (if possible) always eat while comfortably seated, head upright, relaxed,
• do not talk while eating or drinking, largely yawn before eating to ease any constriction,
• eat small amounts, with closed lips, and try to slowly chew and volontarily swallow small quantities,
• take a break between each deglutition, eat slowly, do not mix solid and liquid food,
• drink a small amount of water after each meal to rinse your mouth and clear your throat,
• remain seated a good while after eating or drinking.

Dyspepsia :


Dyspepsia can be defined as a postprandial discomfort or upper abdominal pain. It can also be called indigestion (and in France 'mal au foie' - liver problem!). It is a common situation since 40% of the general population may be more or less concerned.

Main symptoms

Patients have various complaints:

general epigastric discomfort, not always pain as such,

premature satiety (the patient states being hungry but stops eating after only a few bites),

postprandial heaviness, fullness, or bloating,

sensation of incomplete digestion (as if food stayed in the stomach for several hours),

epigastric acidity,

frequent and repeated belching, gulping, hiccups,

nausea, retching, vomiting.

Simple classification

In a simple classification, five types of dyspepsia can be described: 

Small stomach dyspepsia: the patient is hungry but rapidly repleted, he/she experiences epigastric fullness or heaviness soon after eating,

Borborygmus dyspepsia: postprandial bloating with frequent belching associated with dry air swallowing, increased by anxiety, 

Reflux dyspepsia (gastro-oesophageal reflux): retrosternal burning when the patient bends over, when he/she eats more than usual or lies flat. 

Gastric ulcerations or ulcer: precise localised pain wakening the patient at night, relieved by meal or antiacid medication, 

Intestinal motility disorder dyspepsia: abdominal distension, premature satiety, gastric 'heaviness' or fullness, multiple alimentary intolerance, diffuse pain, frequent nausea with irritable bowel syndrome.

Causes of dyspepsia in palliative care

To simplify, causes can be divided into: 

Cancer-related dyspepsia: gastric tumour, massive ascitis, paraneoplastic neuropathy

dyspepsia related to the poor general health state during cancer (candidiasis, reduced alimentation, anxiety), 

treatment-related dyspepsia (abdominal surgery, radiotherapy especially in the abdomen volume, chemotherapy, morphine treatment, other medications), 

associated pre-existing dyspeptic syndromes.

Dyspepsia treatment

Depending on the cause:

Not forgetting auto-medication by the patient at home, which is not always known by the physician (aspirin, gassy water).

A little simple dietary advice can help, such as a more varied diet.

Small stomach dyspepsia can be treated by smaller, more frequent meals.

Drug administration may be reduced (such as anti-inflammatory drugs) but not always stopped.

In the case of gastric acidity, antacid treatment may be prescribed, for example ranitidine, an H2-receptor antagonist avoiding proton pump inhibitors because of their prolonged effect on gastric parietal cells.

Gassy syndromes may be improved by defoaming antiflatulent agents such as simethicone derivatives.

Dyspepsia related to motility syndromes may be treated by prokinetic drugs such as metoclopramide, domperidone, cisapride.

Occlusion syndrome :


During palliative care, occlusion (or obstructive syndrome) generally announces disease progression and the fear of a fatal short-term evolution. It should be totally distinguished from a nascent neoplastic occlusion.

Around 5% of cancer patients suffer from end of life occlusion, mainly those with colon and ovarian carcinoma with a more or less diffuse peritoneal carcinomatosis.

Clinical presentation

Contrary to usual surgical occlusions, palliative care occlusion generally begins slowly and progressively and its site is imprecise. In relation to peritoneal carcinomatosis, it is accompanied by a inflammatory phenomena. The specific date of gas and matter blockage is unclear in these constipated patients. Pain may be due to the tumour itself (compression of nerve plexi) or to intestinal spasms induced by occlusion. Rare cases of vomiting are observed.

At clinical examination, we can distinguish a ballooned abdomen (by dilatation upstream of the lesion) and a flat abdomen (if occlusion is high or total). Palpation also often reveals tumour masses.

Progression can be long: occlusion is often well tolerated over several days or weeks. However, the psychological consequences are important for patients who do not eat, do not pass stools and who permanently suffer from abdominal pain.

Discussing surgery

At the onset of occlusion, the clinical examination should eliminate any surgical indication: an acute onset and noisy symptoms may be due to an acute obstacle which could be solved by a simple surgical act.
However, most often, occlusion is slow to progress, the abdomen is flat, peritoneal masses are found and, in the case of surgery, the surgeon would find himself/herself in an inextricable surgical situation.

An untimely intervention would only add post-surgical pain and the increased risk of numerous adhesions.

Medical treatment

Medical treatment of occlusion is often efficient (mainly corticosteroids at a dosage of 2 - 3 mg/kg of prednisone. When necessary, a nasogastric tube may reduce pain and vomiting. Intravenous infusion is not always necessary.
 
Pain (generally major spasms) should always be treated and small dosages of subcutaneous morphine are not contraindicated when pain is intense.

In colon cancer, an endoprothesis (generally a wired metal endoprothesis) may be installed by colonoscopy providing a more or less regular passage for faecal matter, but with relatively minor colic discomfort.

Preventing vomiting

When occlusion cannot be stopped, a strong analgesic and antispasmodic treatment should be instituted (pethidine may be interesting), avoiding stimulating drugs (such as metoclopramide). When profuse vomiting occurs, octreotide (synthetic somatostatine unfortunately a very costly drug) may be attempted to reduce intestinal secretions. An intermittent nasogastric tube may solve this problem, avoiding a pseudo angina syndrome. In very profuse vomiting, certain physicians would try a per-endoscopic gastrostomy .

Sometimes, episodical vomiting in the absence of intestinal cramps is relatively well tolerated.
Terminal occlusion of peritoneal carcinomatosis is a very slow evolutive death process.

 Nausea and vomiting:

Definitions

Nausea is a multiple sensation: the need to vomit, epigastric pain, distaste for food and general malaise. Nausea is generally relieved by vomiting.

Unfortunately, in palliative care, nausea may be more or less permanent, therefore very toilsome for the patient and often more unpleasant than vomiting itself.

Vomiting is the rejection of eaten matter: it may be beneficial (for instance after food poisoning). When vomiting is repeated, digestive spasms, muscle contractures and the usual accompanying vagal manifestations (bradycardia, hypersialorrhea) end in patient exhaustion. This phenomena is frequently observed during palliative care

Physiopathology

Vomiting occurs in response to the stimulation of the vomiting centre situated in the mid brain. Several brain zones may stimulate this centre in response to stimuli coming from:

the mouth and the pharynx region (olfactory, gustatory and tactile sensations),
the bronchial tree,
the vestibule (motion sickness),
the digestive tract (numerous receptors),
the meninges,
the brain itself (importance of psychology in triggering vomiting).

By studying induced vomiting in animal chemotherapy, a trigger zone has been discovered in the area postrema, i.e. on the floor of the fourth ventricle. These studies showed the importance of serotonin. Stimulating this area stimulates the vomiting centre.

Several neurotransmitters are implied in triggering vomiting:

in the area postrema, dopamine and serotonin (5-hydroxy-tryptamin)
in the vomiting centre, histamine and acetylcholine.

The main causes of vomiting in a palliative setting

Four major causes should be looked for: 

gastrointestinal causes: infiltration or stenosis of the digestive tract, independently of the primitive tumour,

metabolic causes: renal insufficiency, hypercalcaemia, hepatic insufficiency, 

treatment causes: vomiting induced by morphine, antibiotics, chemotherapy, radiotherapy, 

intracranial hypertension: brain metastase, carcinomatous meningitis.

Other causes are either not so frequent or easy to recognize (persisting coughing leading to vomiting, vertigo).

Care should be taken before diagnosing psychogenic vomiting (anxiety of death, repeated medication intake, fear of suffering), which should only acknowledged after the elimination of other causes.

Vomiting complications

They only occur with repeated vomiting:

oesogastric burning which might lead to Mallory-Weiss syndrome (oesophageal hemorrhage),

false passage with deglutition pneumopathies,

metabolic complications: dehydration, alcalosis, renal insufficiency,

impossibility of administrating oral medication (a major hindrance during palliative care),

diet problems: wasting, despair, necessity of parenteral hydration (SC or IV).

Treatment

Treatment depends on the cause.
Firstly, the physician should eliminate a surgical indication, responsible radiotherapy or medication.
Sometimes, vomiting is not frequent and should be respected in order to avoid over-prescription. Vomiting due to morphine is generally transitory.

The main available drugs act either:

on the trigger zone:

antidopaminergic: phenothiazine, haloperidol, metoclopramide, domperidone,

antiserotonin from the setron family.

on the vomiting centre (and vestibular centres)

antihistaminic: diphenhydramine, promethazine,
anticholinergic: scopolamine

on the digestive tract itself

antiserotonin, antidopamin and anticholinergic medications may be useful (see above),
prokinetic medications may also be used: metoclopramide, domperidone, alizapride.

 Constipation:

Definition

Although invalidating and apparently evident to everyone, it is difficult to scientifically define constipation:

it may be reduced defecation frequency (but 5% of healthy persons only pass stools three times per week),

it may also involve difficult defecation (long and strenuous defecation)

Whatever the definition, constipation is an obsession for bedridden patients, particularly during the terminal phase, involving constant abdominal discomfort. More than 65% of patients suffer from constipation.

Causes

During palliative phases, many causes are encountered:

low motility (little walking),
frequent bedridden periods,
opioid intake (and other constipating medication such as anticholinergic drugs),
poor feeding: frequent dehydration and poorly hydrated diet,
pain provoked by defecation of hard stools (patients fearing to pass stools) provoking intracranial hypertension, muscular pain, anal fissure, haemorrhoid.

Diagnosis

Precise diagnosis is necessary before treatment. It is based on: 

rectal examination: is the rectum empty or is there a fecaloma (potentially provoking pseudo-diarrhoea),

 abdominal examination: presence of peritoneal carcinomatosis or of a ballooned abdomen.

Treatment

Preventive treatment

Prevention of constipation is essential as soon as a patient is bedridden. It is done through:

quality hydration (per os if possible),
patient mobilisation as often as possible,
adding fibres to diet,
regular intake of fruits, prunes,
systematic laxative prescription with morphine like analgesics.

Curative treatment

A simple diagram based on the stool consistency may be proposed:
hard stools

They should be treated by a stool softener (stimulating peristalsis on an obstruction can only increase pain):

liquid paraffin (with various taste enhancers),
docusate,
lactulose.

soft stools
They can be treated with peristaltic drugs:

anthracenes (senna),
polyphenolics (bisacodyl).

Use of rectal laxatives (like bisacodyl) may be interesting for fecaloma but these products rapidly provoke irritation.

If necessary, manual evacuation of a fecaloma can be performed under light sedation.