ACUTE ABDOMEN

INTRODUCTION

 Is the most common presenting surgical emergency. It has been estimated that at least 50% of general surgical admissions are emergencies and 50% of them present with acute abdominal pain.

 Studies have shown a 30-day mortality of 4% among patients admitted with acute abdomen. So, it represents a significant part of the general surgical workload. The aim is to differentiate serious causes from less serious causes of acute abdominal pain.

• ‘Acute abdomen’ is a term used to encompass a spectrum of surgical, medical and gynecological conditions, ranging from the trivial to the life-threatening, which require hospital admission, investigation and treatment.

• The acute abdomen may be defined generally as an intra-abdominal process causing severe pain requiring admission to hospital, and which has not been previously investigated or treated and may need surgical intervention.

• The mortality rate varies with age, being the highest at the extremes of age.

• The highest mortality rates are associated with laparotomy for unresectable cancer, ruptured abdominal aortic aneurysm and perforated peptic ulcer.

• Most common causes in any population will vary according to age, sex and race, as well as genetic and environmental factors.

Causes-

A. Gastrointestinal-

1-Gut

Acute appendicitis

Intestinal obstruction

Perforated peptic ulcer

Diverticulitis

Inflammatory bowel disease

Acute exacerbation of peptic ulcer

Gastroenteritis

Mesensteric adenitis

Meckel’s diverticulitis

2-Liver and biliary tract

cholecystitis

cholangitis

Hepatitis

biliary colic

3-Pancreas

Acute pancreatitis

4-Spleen

Splenic infarct and spontaneous rupture

Causes-

B. Urinary tract

Cystitis

Acute pyelonephritis

Ureteric colic

Acute retention

C. Vascular

Ruptured aortic aneurysm

Mesenteric embolus

Mesenteric venous thrombosis

Ischemic colitis

Acute aortic dissection

D. Abdominal wall conditions

Rectus sheath haematoma

E. Peritoneum

Primary peritonitis

Secondary peritonitis

F. Retroperitoneal

Hemorrhage e.g anticoagulants

G. Gynecological

Torsion of ovarian cyst

Ruptured ovarian cyst

Fibroid denegeration

Ovarian infarction

Salpingitis

Pelvic endometriosis

Severe dysmenorrhea

Endometriosis

H. Extra-abdominal causes

Lobar pneumonia

Pleurisy

MI

Sickle cell crisis

Uremia

Hypercalcemia

DKA

Addison’s disease

Acute intermitent porphyria

Classification with age

Children

Gastroenteritis

Mesentric adenitis

Meckel’s diverticulitis

Intussusception

Henoch-schonlein purpura

Adult

Regional enteritis

Ureteric colic

Perforated ulcer

Testicular torsion

Pancreatitis

Relation of pain to embryology

• Intestine and its outgrowths (the liver, biliary system and pancreas)-> midline.

• Irritation of foregut structures

• (oesophagus to the second part of the duodenum)

• ->epigastric area.

• Midgut structures

• (the second part of the duodenum to the splenic

• flexure) ->umbilicus.

• Hindgut structures (the splenic flexure to the rectum)->

• hypogastrium.

Management

• History

• Physical examination

• Management

• History-

– Biodata

Age:

• Mesenteric adenitis in children

• Diverticulitis in elderly

Gender

Characteristics of abdominal pain

• Site

• Time and mode of onset

• Severity

• Nature/Character

• Progression

• Radiation

• Duration

• Cessation

• Exacerbating/relieving factors

• Associated symptoms

Site-pain

Whole abdomen

Peritonitis or mesentric infarction

Right upper quadrant

Acute cholycystitis

Cholangitis

Hepatitis

Peptic ulceration

Left upper quadrant

Peptic ulceration

Pancreatitis

Splenic infarct

Right lower quadrant

Appendicitis

Ovarian cyst Ectopic pregnancy PID Right ureteric colic

Left lower quadrant

Sigmoid diverticular disease

Ovarian cyst

Ectopic pregnancy

PID

Left ureteric colic

Symptoms--Pain

Onset

sudden: perforation of bowel, smooth muscle colic

slow insidious onset: inflammation of visceral peritoneum

Severity

Patient asked to rate pain from 1-10

Ureteric colic is one of worst pains

Character

Aching-dull pain poorly localised

Burning- peptic ulcer symptoms

Stabbing-ureteric colic

Gripping-smooth muscle spasm e.g. intestinal obstruction worse by movement ; wringing of cloth

Progression

-Constant e.g. peptic ulcer

-Colicky e.g. seconds(bowel), minutes(ureteric colic) or tens of minutes (gallbladder

-may change character completely from dull poorly localized pain to sharp pain indicates involvement of parietal peritoneum e.g.appendicitis

Radiation of the pain

Back: duodenal ulcer, pancreatitis, aortic aneurysm

Scapula: gall bladder

Sacroiliac region: ovary

Loin to groin: ureteric colic

Groin: testicular torsion

Cessation-

abrupt ending- colicky pains

resolving slowly-inflammatory pain, biliary pain

Exacerbating/relieving factors-

Movement/Rest-inflammatory conditions

Food- peptic ulcers

Past history

previous surgery

trauma

any medical diseases

Drug history

corticosteroid: mask pain

anti-coagulant: intra-mural hematoma

NSAIDS: gastritis, peptic ulcer

Family history

colon cancer

IBD

Intestinal obstruction

• One of the common cause of acute abdomen

• May lead to high morbidity and mortality if not treated correctly

 It can be classified into two types:

Dynamic (mechanical)

Adynamic

Dynamic

1.Intraluminal: impacted faeces, foreign bodies, gallstones

2.Intramural: tumours, inflammatory strictures, congenital atresia

3.Extramural: adhesion, hernias, volvulus, intussusception, tumours

*also can be divided into:

1. Small bowel obstruction (SBO)

-high ->early perfuse vomiting

rapid dehydration

-low->predominant pain, and central distention

Vomiting delayed

air-fluid levels seen on AXR

2. Large bowel obstruction (LBO)

early pronounced distension, mild pain

vomiting, dehydration late

e.g. -carcinoma

-diverticulitis or volvulus

Adynamic

1.Paralytic ileus (peristalsis is absent)

2.Peristalsis is present in a non-propulsive form e.g. mesentric vascular occlusion

Obstruction can be-

Simple: blockage without interfering with vascular supply

Strangulation: significant impairment of blood supply most commonly associated with hernia, volvulus, intussusception and vascular occlusion

-surgical emergency

Closed loop obstruction: bowel is obstructed at both the proximal and distal end)

Pathophysiology

Irrespective of etiology or acuteness of onset:

Proximal to obstruction

Increased fluid secretion  abdominal distention

Accumulation of gas  abdominal distention

Increased intraluminal pressure

Decreased reabsorption with time and flaccidity to prevent vascular damage from high pressure

Vomiting

Dehydration

Dilatation of bowel

Reflex contraction of smooth muscle  colicky pain

Increased peristalsis to overcome obstruction  increased bowel sounds

If obstruction not overcome  bowel atony

Distal to obstruction: nothing is passed & bowel collapse  constipation

Symptoms

The four cardinal features of intestinal obstruction:

-abdominal pain

-vomiting

-distension

-constipation

Vary according to:-

location of obstruction

age of obstruction

underlying pathology

intestinal ischemia

Abdominal pain

colicky in nature, around the umbilicus in SBO while in the lower abdomen in LBO

if it becomes continuous, think about perforation or strangulation

Vomiting

-starts early in SBO and late in LBO

-vomitus starts with clear color then becomes thick, brown and foul ( faeculent)

-more with lower or complete obstruction

-diarrhea may be present with partial obstruction

Distension

-more with lower obstruction

Constipation

-more with lower or complete obstruction

-diarrhea may be present with partial obstruction

-either absolute (no feces or flatus)<-cardinal in absolute IO

or relative (flatus passed)

Distension

-more with lower obstruction

In strangulation:

• severe constant abdominal pain

• distended abdomen

• fever

• tachycardia

• tender abdomen

Clinical examination:

General examination-

Vital signs

Signs of dehydration –tachycardia, hypotension

dry mucus membrane, decreased skin turgor, decreased urine output

Inspection

distension, scars, peristalsis, masses, hernial orifices

Palpation

tenderness, masses, rigidity

Percussion tympanitic abdomen

Auscultation

high pitched bowel sound or silent abdomen

*Examine rectum for mass, blood, feces or it may be empty in case of complete obstruction

Investigations

• CBC- WBC (neutrophilia-strangulation)

• Hb

• U&E

• Plain AXR

• Sigmoidoscopy (carcinoma, volvulus)

• Double Contrast x-ray ( complete or incomplete)

• CT abdomen

Normal Gas Pattern

AXR

 Stomach

 Always

 Small Bowel

 Two or three loops of non-distended bowel

 Normal diameter = 2.5 cm

 Large Bowel

 In rectum or sigmoid – almost always

Normal Fluid Levels

 Stomach

 Always (except supine film)

 Small Bowel

 Two or three levels possible

 Large Bowel

 None normally

Treatment

• Three main measures-

- GI drainage

- F&E replacement

- Relief of obstruction, usually surgical

Treatment

• Some cases will settle by using this conservative regimen, other need surgical intervention.

• Surgery should be delayed till resuscitation is complete unless signs of strangulation and evidence of acute or closed-loop obstruction.

• Cases that show reasons for delay should be monitored continuously for 72 hours in hope of spontaneous resolution e.g. adhesions with radiological findings but no pain or tenderness

• “The sun should not both rise and set” in cases of unrelieved obstruction.

Indication for surgery:

- failure of conservative management

- tender, irreducible hernia

-strangulation

Type of surgery depends upon the nature of the cause.

Laprotomy is usually done

Decompression of obstruction ( by repair of hernia, complete lysis of adhesion)

Surgical treatment

*Once obstruction relieved, the bowel is inspected for viability, and if non-viable, resection is required.

Indication of non-viability

1.absent peristalsis

2.loss of normal shine

3.loss of pulsation in mesentry

3.green or black color of bowel

• If in doubt of viability, bowel is wrapped in hot packs for 10 minutes with increased oxygen and reassessed for viability.

• Sometimes a second look laprotomy is required in 24-48 hours e.g. multiple ischemic areas.

• Right sided large bowel lesion is treated by right hemicolectomy with covering colostomy