SBAs in Surgery Flashcards
Other name for Hartmann’s?
Proctosigmoidectomy.
Resection of the rectosigmoid colon with closure of the rectal stump and formation of an end/terminal colostomy. Used to be common for diverticular disease and cancer.
Can be reversed in 60-70% cases
Chylothorax
A chylothorax (or chyle leak) is a type of pleural effusion. resulting from lymph formed in the digestive system (chyle) accumulating in the pleural cavity due to either disruption or obstruction of the thoracic duct, which transports up to 4 L of chyle per day, allowing a rapid and large accumulation of fluid in the chest.
50% malignant (60% lymphoma, esp NHL); 25% trauma (esp cardiothoracic surgery)
The best form of fluid therapy is to replace ____
Like with like
Initial first line fluid therapy for trauma patients according to ATLS?
2L warmed Hartmann’s solution
Colloids are useful as osmotically active and stay IV, but are used after initial crystalloid
Typical requirements of fluid and electrolytes in a healthy adult
1-2.5 L H2O
1-2 mmol/kg Na
0.5-1 mmol/kg K
30-40 kcal/kg/day
Third space losses in bowel obstruction (remember ITU pt laparotomy with Mr Tsochazis)
Patients with bowel obstruction sequester huge amounts of fluid within bowel (3rd space). This is salt rich fluid - approx 130 mmol/L Na, 110 Cl, and 10 K
Glasgow Scale Pancreatitis
PaO2 < 8kPa (60mmhg) Age > 55 years Neutrophils: (WBC >15 x109/l Calcium < 2mmol/l Renal function: (Urea > 16mmol/l) Enzymes: (AST/ALT > 200 iu/L or LDH > 600 iu/L) Albumin < 32g/l Sugar: (Glucose >10mmol/L)
3+ Indicate SEVERE disease
ALI in severe pancreatitis
Acute lung injury (ALI) is a complication of systemic inflammation where increased endothelial and epithelial barrier permeability results in leakage of a protein-rich exudate into the alveolar space and interstitial tissues, thus compromising oxygenation and gas exchange. Therefore lungs become susceptible to fluid overload. Presents similarly to acute heart failure.
Bilateral pulmonary oedema, normal cardiac filling pressures, and a ratio of arterial oxygen pressure and inspiratory oxygen concentration (PaO2/FiO2 < 300 mmHg for ALI and < 200 mmHg for ARDS.
CVP fluid challenge monitoring and what is normal?
No defined normal value for CVP. increased value in hypervolaemia and cardiac failure.
If after fluid challenge CVP doesn’t change pt is hypovolaemic. If it increases 2-4 mmH20 and goes back down within 30 min = euvolaemia. A sustained increase >5 mm H2O = overload/CF
Define massive blood transfusion
Replacement of individuals entire circulating volume within 24h
Complications of massive blood transfusion
Stored blood deficient in V and VII.
Additional plt and cryoprecipitate needed to avoid DIC and bleeding
Blood stored at low temp, therfore pt prone to hypothermia
Stored blood high in K, ++K can be a problem
Hypocalcaemia - stored blood anticoagulated with citrate, which Ca ions thus preventing coagulation. In massive transfusion citrate may overwhelm circulating Ca
Hartmanns Composition
Na 131 (all mmol/L) Cl 111 HCO3 29 K 5 Ca 2 Lactate 29
When is Hartmann’s useful, when is it not?
First choice resus fluid according to ATLS.
However lower Na than 0.9 saline (131 vs 150) and inability to add extra potassium (as in 0.9 saline) in pts experiencing salt losses makes its value more limited in medical patients.
SIADH
Hyponatreamia Inappropriately high urine osmolality (>200 mEq/L) Excessive urine Na losses (>30 mEq/L) Decreased osmolality Euvolaemic patient w/o signs of oedema
What should be measured daily in TPN patients?
Blood glucose Urea Creatinine K Na Mg PO4 - hypophosphate esp problematic in TPN pts FBC - prone to sepsis Daily weights and fluid balance charts
** LFTs twice weekly for cholestatic jaundice and fatty hepatitis
In TPN, of which is there more, fats or sugar?
Lipid > Carbohydrate (glucose converted to CO2 resulting in more resp work for the acute surgical pt)
Also 14 g Nitrogen as L-AA
Pneumothorax or Hemo/Chylo thorax?
With a very resonant percussion note - pneumo
With a dull percussion note - something solid must be filling that hole, either blood or chyle
How often should a central line be changed?
Every 5 days
Foramen of Winslow (Omental foramen)
Communication between greater and lesser sac of the abdomen. “Behind” CBD
Anterior: hepatoduodenal ligament (two layers containing CBD, HA and PV)
DAVE: Duct, Artery, Vein, Epiploic foramen.
Posterior: peritoneum covering IVC
Superior: peritoneum covering caudate lobe of liver
Inferior: the peritoneum covering the duodenum and the hepatic artery
Left lateral: gastrosplenic ligament and splenorenal ligament
As the portal vein is the most posterior structure in the hepatoduodenal ligament, and the inferior vena cava lies under the posterior wall, the epiploic foramen can be remembered as lying between the two great veins of the abdomen.
Where is portal triad contained anatomically?
Within hepatoduodenal ligament
Risk factors for gastric cancer
H pylori Pernicious Anaemia Previous gastrectomy Dried fish and cured meats Smoking and Drinking Blood group A (wierd) Atrophic Gastritis Low social status
What are the branched of the internal carotid before it reaches the cranial vault
Trick question - there are none
Oesophagus - structure and blood supply
Top 1/3 is stricated muscle supplied by inferior thyroid artery and drained by inferior thyroid veins and deep cervical lymph nodes
Middle 1/3 blend of striated and smooth muscle supplied by descending aorta, drains via azygous vein and posterior mediastinal LN
Bottom 1/3 smooth muscle, supplied by oesophageal branches of left gastric artery and drained via left gastric vein into portal circulation, and LN around ceoliac plexus.
Define achalasia
Degenration of the Auerbach plexus leads to aganglionosis and failure to relax of the lower oesophageal sphincter. Idiopathic, most likely between 25-50
Similar to trypanosma cruzi (Chagas disease)
Will present as progressive dysphagia to fluids before solids (opposite to cancer). Reason being is that fluids reach LOS quicker and therfore not enough time for relax. Slow eating of food makes more efficient use of LOS. Weight loss late presentation
Plummer Vinson
Severe Iron Deficiency (Koilonychia) + Hyperkeratinasation of proximal 1/3 oesophagus leading to formation of oesophageal web and dysphagia.
Describe the components of the gastro oesophageal sphincter
3 parts*
- LOS - 4cm segment of hypertrophied smooth muscle continous with the distal oesophagus. Maintains pressure 25mmH2O over resting intragastric pressure
- Extrinsic sphincter - skeletal muscle fibres of the right crus of diaphragm which slings around oesophagus. Supports LOS at rest but also contracts with diaphragm during inspiration and abdominal straining
- Physiological - oesophagus projects 2-3 cm into abdominal cavity therefore rise in intra-abdominal pressure will compress this. In addition angle of His provides a flap valve.
* Knowledge important when considering effects of Hiatus hernia which will leave LOS without support
How common is a hiatus hernia?
30% of population >50
50% of those will complain about GORD
8% of hernias are sliding and do not require surgery
Rolling hiatus hernia (paraoesophageal) may require repair due to risk of strangulation.
Los Angeles classification of Oesophagitis severity
Grade 1 - small mucosal breaks, limited to <2 mucosal folds
Grade 2 - mucosal break >5mm long, limited to <2 mucosal folds
Grade 3 - >2 mucosal folds but <75% oesophageal circumference
Grade 4 - circumferential mucosal breakdown >75% of circumference
Complications of oesophagitis
Bleeding (usually small volume chronic)
Barrett’s
Malignancy
- Conservative (smoke, drink, diet)
- Medical (PPI & H2 antagonists) - e.g. omeprazole and ranitidine. These are complimentary therapies
- Endoscopy to avoid missing early malignancy may be required
- Surgery if symptoms life threatening or v. severe
Complications of partial gastrectomy / gastrectomy
\++ Risk of malignancy Obstructions Malabsorbtive symptoms - B12, Iron, B9 Early satiety (often desired outcome) Dumping syndrome - uncontrolled release of large volume of chyme into proximal bowel leads to rapid large volume fluid shifts (transient) causeing hot flushes, palpitations, syncope. Feels similar to hypo attack
What drug do you give in oesophageal varices?
Propranolol
What is the name of the balloon inserted into oesophagus to put pressure on variceal bleed?
Sengstaken - Blakemore tube
Why can you get RIF pain in perforated PUD?
As fluid tracks into peritoneal gutter (gravity), causing inflammation there
Kocher’s incision
Mostly used in open biliary surgery. Incision 3-5 cm below costal margin.
Anterior rectus sheath exposed and divided along line of incision exposing rectus muscles.
These are divided with care to ensure haemostasis when branches of superior gastric vessels sacrificed.
Eighth and Ninth intercostal nerves lie between internal oblique and transverse muscles - often 8 is sacrificed
Lanz Incision
Transversely crosses McBurney’s point (2/3 between pubic symphysis and right ASIS. Incision starts 2 cm inferomedial to the right ASIS and extends medially for 5–7 cm.
Good access to appendix and caecum.
Its transverse lie tends to make the iliohypogastric and ilioinguinal nerves more susceptible to division. This can predispose the patient to later inguinal herniation.
Inguinal Incision
Incision 1 cm above and parallel to the inguinal ligament, from the inner to the outer inguinal ring.
Through the SC fat and Camper’s fascia to expose the aponeurosis of the external oblique
Incision of the aponeurosis of the external oblique from the external inguinal ring to the level of the internal inguinal ring.
ID and protect ileoinguinal nerve
Blunt mobilization of the spermatic cord
Blood supply to the stomach
All blood derived from coeliac plexus (T12).
Lesser curve supplied by L and R gastric vessels.
Greater curve by R and L gastroepiploic vessels
R gastroepiploic a branch of gastroduodenal, which passes just underneath D1, and is susceptible to erosion by DU (rapid bleed and high mort)
How long can a pt have malaena after bleeding stopped
As long as 72h (even longer with constipation)
Zollinger-Ellison
Gastrin-like hormone secreting tumour of the pancreas. Hyperacidity of stomach and therefore severe and extensive ulcers
Gallstone composition
15% cholesterol
5% pigment stones
80% mixed
Most common cause of pancreatitis
Gallstone (45%)
Alcohol (25%)
Rest
Risk factors for gallstones to elicit in Hx
Race (black and asian) Hypercholesterolaemia (or v. fatty diet) Obesity Oestrogen state - COCP, prego, PCOS Haemolytic states Crohn's - after surgery loss of terminal ileum
Mirizzi’s syndrome
Common hepatic duct obstruction caused by an extrinsic compression from an impacted stone in the cystic duct or Hartmann’s pouch of the gallbladder
Causes of cholecystectomy postoperative jaundice
Gallstone retention
Recurrence
Biliary sepsis
Fibrotic stricturing (usually if too enthusiastic with electrocautery - blunt disssection preferable)
Inappropriate ligation of cystic duct - anatomy of that region displays high variability
CC and PBC
20-30% PSC pts will develop CC
Majority (vast) of CC pts will have PSC and IBD underlying
Liver flukes
Opisthorchis viverrini
Clonorchis sinensis
Whipple’s procedure
Cancer of the head of pancreas. Removal of gastric antrum, pylorus, proximal duodenum, gallbladder, cystic duct, head of pancreas.
common hepatic duct preserved and anastamosed to blind loop of jejunum. Jejunum anastamosed to remant pancreas and stomach
Blood film post splenectomy
Howell Jolly bodies - DNA remnants
Target cells - RBC with membrane abnormality
Ecchinocytes - RBC with membrane abnormality
Pappenheimer bodies - granules in iron loading cells
Why is pancreatitis common after splenectomy?
Tail of pancrease shares blood supply with spleen
Why do pts need antiplatelet therapy post splenectomy?
Paradoxical increase in plt count. High risk of thrombosis in first 3 weeks (can persist occasionally).
Aspirin ± Dipyridamole
Vaccinations in hyposplenism
Encapsulated bacteria
Step Pneumo
Meningococcus B and C
HiB
+ Influenza
± prophylactic penicillin V
How much pancreatic juice secreted in one day
1500 mL
Endocrine functions of pancreas
4
Insulin (B cells)
Glucagon (A cells)
Somatostatin (D cells)
Gastrin (G cells)
Pancreatic pseudocysts
Late complication of pancreatitis, occurs approx 20% cases. ++ chance with %% aetiology
6-8 weeks after initial attack
Persistantly raised amylase with no systemic upset and pyrexia. DDx chronic pancreatitis
Collection of pancreatic juices enclosed by non-epithelial (hence pseudocyst) fibrous layer. Most commonly in lesser sac.
Can become infected (abscess), rupture, erode, pressure (duodenal obstruction)
If small, conservative If large (>6cm), US/CT guided drainage or open pancreatectomy
Villous adenoma vs tubular adenoma
Villous colonic adenomas characteristically secrete large amounts of K rich mucus. Only symptoms may be mucous and hypokalaemia. Far higher malignant potential due to level of epithelial dysplasia
Liver resection in colonic cancer
As long as mets confined to single lobe (gadolinium enhanced MRI to confirm), liver resection and agressive management increases survival to 30% (remember 5yr prognosis for Dukes D cancer 5%)
Excising tumours of the transverse colon
Technical difficulty in creating colon:colon anastamosis means that left hemicolectomy and transverse colectomy have fallen out of favour. If possible, extended R hemicolectomy
Post stoma formation and electrolytes
Immediately following stoma formation, large quantities of Na rich secretions may be lost = hypokalaemic metabolic alkylosis as Na conserved in exchange for K and H in renal tubules.
Short term complication
Managing sigmoid volvulus
Sigmoidoscopy and insertion of flatus tube.
If failure or bowel infarction - laparotomy and colectomy
Is OP a complication of CD?
No, although can be caused by long term steroid use. Not disease itself though
Saint’s triad
Association between diverticula, cholelithiasis and hiatus hernia which occurs more frequently in western societies
Where is the site of most diverticula and why not the rectum?
95% sigmoid colon
Outpouchings between taenia coli which are not true diverticula.
Within rectum, taenia coli become fused.
What do you give a IBD patient intolerant to azathioprine?
6-mercaptopurine
Although this is the active metabolite of azathioprine (which is not tolerated by 1/3 pts), 50% of those intolerant to azathioprine will respond well to 6mp
First line mesalazine/sulphasalazine
Second line azathioprine/6mp
Third line therapy is methotrexate for CD and ciclosporin for UC
4th line therapy is biologics - infliximab
