Small Bowel Flashcards
what are the most common types of hernia
inguinal hernias
definition of a hernia
protrusion of part or whole of an organ or tissue through the wall of the cavity that normally contains it
what are the 2 main subtypes of inguinal hernia and what is the difference between them
direct inguinal hernia = bowel enters inguinal canal directly through weakness in the posterior wall of the canal (termed Hesselbach’s triangle)
indirect inguinal hernia = bowel enters inguinal canal via the deep inguinal ring, they arise from incomplete closure of the processus vaginalis
what type of patients do direct inguinal hernias usually occur in
older patients , secondary to abdominal wall laxity or a significant increase in intra-abdominal pressure
what are the borders of Hesselbach’s triangle
lateral = inferior epigastric vessels
medial = lateral border of rectus abdominis
inferior = inguinal ligament
what is the relation of direct and indirect inguinal hernias with the inferior epigastric vessels
direct = medial to inferior epigastric vessels
indirect = lateral to inferior epigastric vessels
risk factors for inguinal hernias
male
increasing age
raised intra-abdominal pressure; chronic cough, heavy lifting, chronic constipation
obesity
clinical features of reducible inguinal hernias
lump in the groin which will disappear with minimal pressure or when the patient lies down, there can be mild to moderate discomfort which can worsen with activity or standing
what is an incarcerated inguinal hernia and what are its clinical features
incarcerated means that the bowel cannot be reduced back into the abdominal cavity
painful, tender, erythematous and may be signs of bowel obstruction if the bowel lumen is blocked
what is a strangulated inguinal hernia and what are its clinical features
strangulated means that its blood supply has become compromised leading to the bowel becoming ischaemic
presents as an irreducible, tender and tense lump with the pain being out of proportion to clinical signs, also with clinical features of obstruction
investigations into inguinal hernias
clinical diagnosis. if uncertain then MRI is recommended first line imaging
for features of obstruction or strangulation then CT will be required
management of inguinal hernias
all patients with symptomatic inguinal hernias should be offered surgical intervention
any patient showing signs of strangulation requires urgent surgical exploration
surgical; open mesh repairs are preferred in primary inguinal hernias, or laparascopic repairs which are preferred in bilateral or recurrent inguinal hernias
what are the indications for laparascopic repair of inguinal hernia rather than open mesh repair
bilateral
recurrent
what are the indications for urgent surgical intervention in inguinal hernias
incarcerated
obstruction of the bowel
strangulation leading to bowel ischaemia and potentially infarction
what are femoral hernias and why are they important to identify
occur when the abdominal viscera or omentum pass through the femoral ring and into the potential space of the femoral canal
high rate of strangulation
what are the anatomical borders of the femoral canal
superior border = femoral ring
anterior border = inguinal ligament
posterior border = pectineus
lateral border = femoral vein
medial border = lacunar ligament
risk factors for femoral hernias
female
pregnancy
raised intra-abdominal pressure
increasing age
investigations into femoral hernias
USS or CT abdo-pelvis
management of femoral hernias
all femoral hernias should be managed surgically, ideally within 2 weeks of presentation due to the high risk of strangulation
high vs low approach
high = above inguinal ligament (preferred)
low = below inguinal ligament
what forms the borders of the femoral triangle
superior = inguinal ligament
lateral = medial border of sartorius muscle
medial = medial border of adductor longus
why do all femoral hernias require surgical intervention
due to the high risk of strangulation
what is an epigastric hernia
occurs in the upper midline through the fibres of the linea alba
secondary to chronic raised intra-abdominal pressure such as with obesity, pregnancy or ascites
what is a paraumbilical hernia
herniation through the linea alba around the umbilical region
secondary to chronic raised intra-abdominal pressure
what is a spigelian hernia
rare form of abdominal hernia that occurs at the semilunar line (the tendinous lateral border of the rectus, where the aponeuroses fuse) around the level of the arcuate line
present as small lump at the lower lateral edge of the rectus abdominus
they have a high risk of strangulation so should be repaired urgently
what is an obturator hernia
hernia of the pelvic floor, occurring through the obturator foramen into the obturator canal
present with mass in upper medial thigh and often patients will have features of small bowel obstruction
what is a Littre’s hernia
very rare form of abdominal herniation of a meckel’s diverticulum
what is the name of the hernia that describes herniation of a Meckle’s diverticulum
Littre’s hernia
what is gastroenteritis
term used to describe inflammation of the gastrointestinal tract, usually considered infective in origin
what are the common symptoms of gastroenteritis and how does the duration of symptoms affect the thoughts on the causative agent
diarrhoea, vomiting, abdo pain
bacterial toxins = hours
viruses = days
bacteria = weeks
parasites = months
risk factors for gastroenteritis
poor food prep
immunocompromised
poor personal hygiene
why is recent use of antibiotics important in the context of gastroenteritis
could suggest potential C. difficile infection
what are some important things to ask in the history of a patient presenting with gastroenteritis
recent travel abroad
affected family members
recent antibiotic use
bowel movements (blood, mucus)
what investigation is often warranted in gastroenteritis
stool culture - especially in cases with blood and mucus in the stool
management of gastroenteritis
rehydration - encourage oral fluid intake; if unable to tolerate fluids then admission for an IV fluid rehydration
exclusion from work
self-limiting
common viral causes of gastroenteritis
norovirus - most common
rotavirus - infants and young children
adenovirus - children
common bacterial causes of gastroenteritis
campylobacter - most common cause of food poisoning
E. coli - most common cause of travellers diarrhoea
salmonella
shigella
(all gram negative bacillus)
common bacterial toxins that cause gastroenteritis
bacterial toxins arise from;
S. aureus
Bacillus cereus - found in reheated rice
clostridium perfringes
vibrio cholera - contaminated water supplies
parasitic causes of gastroenteritis
crytposporidium
entamoeba histolytica
giardia intestinalis
schistosoma
what investigation should you do if suspecting of a parasitic gastroenteritis
stool culture for ova, cysts and parasites
infection with what bacteria can result in toxic megacolon
C. difficile
what is the most common causative organism of hospital-acquired gastroenteritis
C. difficile
what does dysentery mean
gastroenteritis characterised by loose stools with blood and mucus
gastroenteritis ceasing within a few hours was most likely caused by what
bacterial toxins
what type of bacteria is E. coli
gram negative bacillus
what pathogen most commonly causes travellers diarrhoea
enterotoxigenic E. coli
