Acute Abdomen, its sign symptoms, History, Examination and Treatment

INTRODUCTION;
Acute abdomen 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. 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

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:

1. Dynamic (mechanical)
2. Adynamic
   

Dynamic;

1.Intraluminal: impacted faeces, foreign bodies, gallstones

2.Intramural: tumours, inflammatory strictures, congenital atresia

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

It can also 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

• 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