Acute Care Surgery Flashcards
What is the differential for groin masses?
MINT: Malformation: hernia, testicular stuff Infectious/Inflammatory Neoplastic Traumatic
What to think: groin mass that protrudes with standing?
Hernia
What is a hernia?
Protrusion of tissue or organs through a defect, usually in the abdominal wall
What is the difference between a reducible, incarcerated and a strangulated hernia?
Reducible: contents in the sac can be pushed back through the defect into the peritoneal cavity
Incarcerated: contents are stuck in hernia sack
Strangulated: Compromised blood flow to the herniated organ
What clues on history and PE point to incarcerated hernia progression to strangulated? Why?
- Fever, tachycardia, elevated WBC, plus redness of overlying skin
- Due to blood flow compromise, irreversible ischemia and necrosis
What is the pathophys of a direct inguinal hernia?
Acquired weakness in the abdominal wall, usually due to chronic straining
What is the pathophys of an indirect inguinal hernia?
Congenital: usually due to a patent processes vaginalis
What is the pathophys of a femoral hernia?
Multiple pregnancies dilate femoral veins and widen the femoral canal
Which rings do indirect inguinal hernias traverse?
deep and superficial
Which rings do direct inguinal hernias traverse?
superficial
Why are femoral hernias more prone to incarceration?
femoral ring is very rigid and unyielding
What is a Richter’s Hernia?
- Only part of the circumference of the bowel wall is trapped within the hernia sac
- Herniated segment can become strangulated and result in ischemic changes
What is a sliding hernia?
Indirect hernia: retroperitoneal organ typically slides with the sac and essentially makes up the posterior wall of the sac
How to diagnose a hernia?
Clinically: history and physical. Patient stands, clinician inserts finger at level of external ring. If patient coughs and a bulge is palpated, a hernia is present.
When do we use imaging to confirm a hernia?
CT in an obese patient, or with a Spigelian hernia since they lie between 2 layers of bowel wall and are difficult to palpate
How to treat an asymptomatic hernia?
- Observe! Except: femoral hernias or inguinal hernias in infancy (wait until premie out of ICU)
- Eventually will become symptomatic and need repair
How to treat indirect hernia?
Open the sac anteriorly, reduce any contents and perform a high ligation at the internal ring of the hernia sac
How to treat a direct hernia?
Do not open the sac (no patent processus vaginalis) and reinforce floor with mesh
How to treat a femoral hernia?
- Emergently!
- Medial to the femoral vein and inferior to the inguinal ligament
- High incarceration risk
What do we do for incarcerated hernia?
Attempt reduction, then repair semi-electively
What do we do for strangulated hernia?
Urgent surgery. Do not try to reduce - necrosis of bowel will cause peritonitis
How do we treat an umbilical hernia?
Usually corrects on its own Repair it if: - Persists > age 4 - Defect > 2cm - Progressive enlargement after age 2
What are complications of hernia repair?
- Nerve injury due to transection, stretching, cauterization or entrapment of sutures or by scar tissue around the mesh
- Testicular ischemia: swollen painful testicle after surgery due to venous drainage in spermatic cord being cut
- Recurrence
What is the significance of SBO in the absence of an abdominal scar?
- Removes most common benign etiology of SBO
- less likely to resolve with conservative treatment, may need emergency surgery
What is the most common cause of SBO worldwide?
Hernias
What is the Howship-Romberg sign?
- Pain in the medial thigh with abduction, extension or hip internal rotation
- Due to compression of obturator nerve by obturator hernia
What is the significance of severe abdominal pain and localized tenderness in association with an SBO?
- Suggests strangulated SBO - vascular perfusion is impaired leading to intestinal ischemia and necrosis
- Surgical intervention needed
What are the 4 cardinal signs of strangulated bowel?
Fever
Tachycardia
Leukocytosis
Localized abdominal tenderness
What is a closed loop obstruction?
- Segment of intestine obstructed proximally and distally
- Gas and fluid accumulate in segment and cannot escape
- Causes rapid strangulation with ischemia and perforation
What are the most common causes of an SBO
- Intra abdominal adhesions due to prior abdominal surgery
- Hernia
- Gallstone ileus: gallstone at ileocecal valve
- Crohn’s
- Intususception
- Neoplasm
- Volvulus
What are the common causes of adhesions leading to SBO?
- Surgery: appendectomy, colorectal resection, gyn procedures
- Inflammatory: appendicitis, diverticulitis
What are the mechanisms of fluid loss in SBO?
- Repeated emesis
- Refusal of oral intake
- Transudative loss into peritoneal cavity
- THIRD SPACING: Stasis in lumen: bacterial overgrowth –> increased hydrostatic pressure –> fluid accumulates in bowel wall and starling forces change: net filtration of fluid, electrolytes and protein into bowel wall and lumen
What labs to get when working up SBO? Why do they matter?
CBC
Chemistry panel
Serum lactate
Need to assess dehydration, possibility of bowel ischemia or compromise
What imaging is recommended for SBO?
- Abdominal series
2. CT abdomen and pelvis with oral and IV contrast
How to tell small bowel vs. large bowel on X-ray?
Small: plica circulates all the way through the bowel
Large: hausfrau only halfway through the bowel
What do we see on abdominal series for SBO?
- Dilated loops of small intestine
- Air-fluid levels
- Bowel stacking
How is complete SBO different than partial SBO?
Complete: intestinal lumen entirely occluded: no passage of gas or fluid
Partial: gas and fluid are able to pass
How are symptoms of complete and partial SBO different?
Complete: colicky ab pain, N/V/obstipation
Partial: similar symptoms but develop more slowly, and continue to pass gas and stool beyond 12 hours after symptom onset
Why is it important to distinguish between complete and partial SBO?
Partial: low risk of strangulation. Can manage non-op
Complete: substantial risk of strangulation, may require surgical intervention
How to distinguish between small and large bowel obstruction?
Depends on etiology and location. Proximal colon more likely to be mistaken since luminal contents similar to SB.
LBO: gradually increasing abdominal pain, progressive dissension, constipation and occasional feculent vomiting. Longer intervals between pain and pain in suprapubic area
What are common causes of LBO?
Colon cancer: apple core
diverticulitis
volvulus: bird beak to LLQ
How to distinguish between postoperative ileus and SBO?
CT
What are complications/sequelae of SBO?
Emesis and third spacing: dehydration, pre renal azotemia and hypochloremic hypokalemic metabolic acidosis
What are initial management steps of an SO?
- Aggressive fluid resuscitation
- Place NG tube to evacuate air and fluid
- Electrolyte repletion
How do we treat complete SBO?
- Manage conservatively for 12-24 hours
- If no clinical improvement: surgical intervention
When is it appropriate to proceed to OR with SBO?
Signs or symptoms of peritonitis or bowel ischemia
What to do if you suspect nonviable bowel during laparotomy for SBO?
Bowel resection
What is the management of early postoperative SBO?
Avoid re-operation on early post-op SBO unless clear evidence of peritonitis or bowel compromise