CLINICAL FEATURESOF

INTESTINAL OBSTRUCTION

SOUMEN CHAKRABORTY(INTERNEE)

Clinical features vary according to:-The location of the obstruction.

The duration of obstruction.The underlying pathology.The presence or absence of intestinal ischemia..

Cardinal features include:-

INTESTINAL OBSTRUCTI

ON

PAIN

VOMITING

DISTENTION

OBSTIPATION

PAINPAIN is the first symptom encountered, it

occurs suddenly and is usually severe..It is colicky in nature and usually centred on

the umbilicus (small bowel) or lower abdomen (large bowel).

The pain coincides with the increasing peristaltic activity..

With increasing distension, the colicky pain is replaced by a mild & m0re constant diffuse pain.

PAIN (CONTD.)The development of severe pain is suggestive

of strangulation, especially if that pain is continuous.

Colicky pain may not be a significant feature in post operative simple mechanical obstruction and pain does not occur in paralytic ileus..

VOMITINGMore proximal the obstruction, more the

frequency.The more distal the obstruction, the longer

the interval between the onset of symptoms and appearance of nausea & vomiting.

As obstruction progresses, the character of vomitus alters from digested food to faeculent material, as a result of the presence of enteric bacterial overgrowth..

Vomitus- food material, GI secretions.. Long standing low small bowel obstruction- feculent

material. Strangulation-blood.

DISTENSIONIn the small bowel, the degree of distension is

dependent on the site of obstruction & is greater the more distal the lesion.

Central abdomen is usually distended in small bowel obstruction; peripheral in small bowel obstruction..

Distension is a late feature of colonic obstruction.

CONSTIPATIONMay be ABSOLUTE(neither faeces nor flatus

is passed) or RELATIVE(only flatus is passed) Absolute constipation(obstipation)is a

cardinal feature of complete intestinal obstruction. Exceptions:-

Richter’s hernia Gallstone ileus Mesenteric valvular obstruction Functional obstruction associated with pelvic

abscess All cases of partial obstruction(in which diarrhoea

may occur)

VISIBLE PERISTALSISVisible peristalsis may be present which may

be provoked by gently flicking the abdominal wall.

Few images of visible peristalsis in obstruction

OTHER MANIFESTATIONSDehydrationHypokalemiaPyrexiaAbdominal tendernessBowel sounds

DEHYDRATIONMost common in small bowel obstruction

because of repeated vomiting and fluid sequestration resulting in

dry skin and tongue, poor venous filling and sunken eyes with oliguria

Blood urea level & haematocrit rise , giving a secondary polycythaemia.

HYPOKALEMIANot a common featureAn increase in serum potassium, amylase or

lactate dehydrogenase may be associated with the presence of strangulation.

PYREXIAPyrexia is rare & may indicate:

The onset of ischaemia Intestinal perforation Inflammation or abscess associated with the

obstructing disease.

Hypothermia indicates septicaemic shock or neglected case of long duration..

ABDOMINAL TENDERNESSLocalised tenderness indicates impending or

established ischaemia.The development of peritonitis indicates

impending or overt infarction &/or perforation.

In case of large bowel obstruction, it is important to elicit these findings in the right iliac fossa as the caecum is most vulnerable to ischaemia

BOWEL SOUNDSHigh pitched bowel sounds are present in

majority of patients with intestinal obstruction.

Bowel sounds may be scanty or absent if the obstruction is long standing and the small bowel has become inactive.

EXAMINATION

1. PHYSICAL EXAMINATION

(a) Inspection (b) Palpation(c) Percussion(d) Auscultation

2. Rectal Examination

Inspection In early stage ‘visible peristalsis is the only sign.Abdominal distension is the late sign.ØHernial orfices, surgical scars must be inspected.PalpationØDuring colic there may be muscle guarding. Slight tenderness may be present between attacks of pain. ØTenderness and rigidity at the sight of obstruction usually indicates strangulation.PercussionOnly reveals resonant note of gaseous distension of bowel.AuscultationØPresence of loud borborygmi, coinciding with intestinal colic is very diagnostic.ØIn case of intestinal obstruction “Silent abdomen” suggests paralytic ileus.

CLINICAL EXAMINATIONS

RECTAL EXAMINATION

Presence of mass on rectal examination within or outside the lumen will give a clue to diagnosis. Presence or absence of feces in rectum should be noted. Absence means obstruction is higher up. If present it should be studied for presence of occult blood, which include mucosal lesion e.g. cancer, intussusception or infarction. Sigmoidoscopy should be done if colonic obstruction is suspected.

Proximal small bowel

Distal small bowel

Large bowel

Severe vomiting Moderate vomiting Late vomiting

Less distension Central distension Early distension , pronounced

Colicky pain Central abdominal pain

Less pain

Constipation late Varies in appearance Constipation is early feature

Severe dehydration

Moderate Less dehydration

Comparison of clinical aspects

STRANGULATION

STRANGULATIONStrangulating Intestinal Obstruction is a

SURGICAL EMERGENCY. The features are:- Constant pain , severe pain. Generalised tenderness with rigidity & peritonism Shock , especially if resistant simple fluid

resuscitation.

When strangulation occurs in an external hernia, the lump is tense, tender and irreducible and there is no expansile cough impulse. There is erythema or purplish discolouration of the above skin with underlying ischemia.

INTUSSUSCEPTION

INTUSSUSCEPTIONClassical presentation is with episodes of

screaming and drawing up of the legs in a previously well male infant.

During attacks the child appears pale ; between episodes he may be listless.

Vomiting may or may not occur at the outset but becomes conspicuous and bile stained with time.

Initially passage of stool may be normal, whereas, later, blood and mucous are evacuated- the ‘redcurrant jelly’ stool.

INTUSSUSCEPTION(contd...)Classically abdomen is not usually distended.A lump that hardens on palpation may be

discerned but this is present in only 60% of cases.

There may be associated feeling of emptiness in the right iliac fossa (the sign of Dance).

On rectal examination, blood stained mucus may be found on the finger.

Occasionally in extensive ileocolic or colocolic intussusception, the apex may be palpable or even protrude from the anus.

INTUSSUSCEPTION(contd...)If unrelieved, progressive dehydration and

abdominal distension from small bowel obstruction will occur, followed by peritonitis secondary to gangrene.

CAECAL VOLVULUS

SIGMOID VOLVULUS

VOLVULUSCAECAL VOLVULUS:-

More common in females in fourth and fifth decades and usually presents acutely with the classic feature of obstruction.

Ischemia is common. At first the obstruction may be partial, with the

passage of flatus and faeces. In 25% of cases examination may reveal a palpable

tympanic swelling in the midline or left side of abdomen.

The volvulus typically results in the caecum lying in the left lying in the left upper quadrant.

VOLVULUSSIGMOID VOLVULUS:-

Symptoms resembles that of large bowel obstruction.

Abdominal distension is an early and progressive sign, which may be associated with hiccough and retching.

Constipation is absolute. In some patient, the grossly distended torted left

colon is visible through the abdominal wall.