Intestinal Obstruction

Question 1

Definition

Answer 1

Stoppage of onwards passage of intestinal contents ( food, digestive juices, gases )

Question 2

Different ways to classify intestinal obstruction

Answer 2

Mechanical , paralytic

High , low,

Acute, chronic, acute on chronic

Simple, closed loop, strangulation

Question 3

Different areas of obstruction in intestines

Answer 3

Intraluminal
Intramural
Extramural
Mesenteric vascular obstruction
Others

Question 4

Causes of intraluminal obstruction

Answer 4

Foreign bodies
Pedunculated tumors
Worms
Impacted faeces
Bezoars
Gallstones
Faecolith

Question 5

Intramural causes of obstruction

Answer 5

Tumors
Atresias
Anorectal anomalies
Aganglionic megacolon
Intussusception

Question 6

Extramural causes of obstruction

Answer 6

Hernia
Adhesions / bands
Volvulus

Question 7

Pathophysiology of simple obstruction

Answer 7

Distal segment obstruction

Proximal segment distension with accumulation of fluid, food and gases (loss of absorption , increase in secretion ) , increase in intraluminal pressure (wall edema, integrity loss, bacteria translocation, venous stasis and occlusion, arterial stasis )

Collapse of distal segment

Dehydration and electrolyte imbalance with loss of GI secretion (accumulation in lumen and vomiting +loss in peritoneum and bowel wall ) leading to hypokalemia , Hyponatremia , hypochloremia , metabolic alkalosis or acidosis and kidney affected

Question 8

Closed loop obstruction pathophysiology

Answer 8

No content entering or leaving segment in the loop
Shows same pathophysiology as simple obstruction

Question 9

Complication in closed loop if rapid distension

Answer 9

Rupture

Question 10

Example of disease causing closed loop obstruction

Answer 10

Hernias
Adhesions
Volvulus
Obstructing colonic mass with competent IC valve

Question 11

Can you have an obstruction that is simple, closed loop, and strangulated

Answer 11

Yes

Question 12

Strangulation obstruction pathophysiology

Answer 12

Sequestration of blood leading to hypovolemia

Dilatation of intramural lymph channels bacteria and toxins diffusion can lead to peritonitis, septicemia, endotoxin shock

Bleeding into lumen , wall , peritoneal cavity

Bowel wall infarction leading to anaerobic organisms multiplication

Question 13

Causes of death in bowel obstruction

Answer 13

Shock
Dehydration
Electrolyte imbalance and metabolic disturbance
Peritonitis
Septicemia
Renal failure
Respiratory failure
Multiple organ failure

Question 14

main symptoms and signs

Answer 14

Pain (colicky if mechanical )
Vomiting
Constipation
Abdominal distension

Question 15

Vomiting occurs early in disease in low or high bloackage

Answer 15

High blockage

Question 16

Type of constipation in intestinal obstruction

Answer 16

Absolute with no faeces nor flatus

Question 17

Constipation occurs early in low or high blockage

Answer 17

Low blockage

Question 18

History of presenting complaints

Answer 18

Onset
Relationship between vomiting , abdominal distension, constipation, abdominal pain
Progression of pain , constipation

Question 19

Systemic enquiry important findings

Answer 19

Fever
Weight loss

Question 20

Important past medical history

Answer 20

Previous surgery (adhesions, anastomotic structure )
Spinal injury
Retroperitoneal hemorrhage
Electrolyte imbalance (hypokalemia , hypomagnesemia )

Question 21

General features found on examination

Answer 21

Dehydration
Shock presentation

Question 22

Examination inspection findings

Answer 22

Abdominal distension
Asymmetry
Visible peristalsis
Scars
Hernia orifices

Question 23

Palpation findings on examination

Answer 23

Hernia orifices
Tenderness
Rebound tenderness

Question 24

Percussion findings on examination

Answer 24

Tympanitic

Question 25

Auscultation findings on examination

Answer 25

Bowel sounds Increased volume or pitch possible

Question 26

Rectal examination findings

Answer 26

Feeling of faeces Tumors

Question 27

Investigations

Answer 27

Plain X ray CT scan CHest x ray Urea and electrolytes FBC Barium enema

Question 28

Position of patients on plain x ray

Answer 28

Erect Supine

Question 29

Differential diagnosis of intestinal obstruction

Answer 29

Causes of mechanical obstruction Causes of paralytic ileus Acute pancreatitis Severe constipation Pseudo obstruction Other causes of acute abdomen

Question 30

Treatment of intestinal obstruction

Answer 30

Resuscitation (fluid and electrolyte imbalance correction ) Bowel decompression with NG tube Antibiotics Pain relief and sedation

Question 31

Factors affecting prognosis

Answer 31

Interval between onset and treatment Level of obstruction Causes of obstruction Age of patient Adéquation of rescusitation Viability of bowel Pre existing disease