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General Surgery Michael Grant

Notes based on QUB online Med Portal lectures, QUB student manual, Oxford Clinical handbook and various external online resources

Surgery: Page 2 of 85

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Acute Abdomen

The emergencies of the GI tract are important to recognise and treat; patients need to have adequate resus followed by specific management. Surgical emergencies can be divided classified by their location: l Oesophagus Acute dysphagia l Presentation - cannot swallow May have benign stricture or malignant neoplasm (especially exophitic) l Triggered by food bolus or tablet l Treatment § Remove bolus by endoscopy then deal with underlying oesophageal disease Perforation l High mortality l

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Causes – Iatrogenic 55% (i.e. Post-OGD esp. if there is benign/malignant stricture), Boerhaave syndrome 10% (excessive vomiting), pill esophagitis, Barrett's oesophagus, infectious ulcers (e.g. Herpes in AIDs), corrosives l Presentation – acute chest/abdominal pain, odynophagia, l CXR - Air in mediastinum and subcutaneous emphysema (crackling sensation over skin) and, if Boerhaave, + exudative pleural effusion l Treatment § Benign causes are treated with surgery (followed by PPI, ABx) § If due to malignant ulcer, then intubation Bleeding l Causes - Oesophagitis, Mallory Weiss, Varices l Variceal bleeding – tends to be most severe & can be catastrophic – use Rockall Score and/or AIMS65 l Treatment of Varices § Firstly, stabilise: Fluids, Blood transfusion, IV Omeprazol (80mg – 40mg BID) somatostatin/octreotide (25mcg bolus then 25mcg/hr IVI) GH–inhibiting hormone & synthetic; are vasoconstrictors), Erythromycin (Promotility, enhances visualization on OGD, 3 mg/kg IV over 20mins prior to OGD), Sengstakenblakemore tube, § Move on to definitive treatment, e.g. band ligation/stent insertion (later especially if longterm alco) Stomach/duodenum Perforation l Presentation - abdominal pain, rigidity/prostration, peritonism, shock, pneumoperitoneum X-ray l Treatment - ABx, resuscitate, followed by surgical repair Bleeding l Presentation: Haematemesis +/- Melaena, if severe; Increased HR>90, Fall BP3mm) l Treatment: Antibiotics, analgesics, early surgery Cholangitis l Presentation: Acute RUQ pain, +/- Pyrexia, +/- Rigors (also seen in Charcot's triad for ascending cholangitis; if low BP and altered mental status, then it is Reynolds' pentad), Obstructive jaundice l

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Yellow skin, sclerae, pruritus, pale stools, dark urine, +/- Pain, Murphey’s sign, +/- Courvoisier’s sign (palpably enlarged, non-tender gallbladder, accompanied with painless jaundice means the cause is unlikely to be gallstones) CT – dilated bile ducts, mass in pancreas, gallstones Establish diagnosis – Gallstones, Ca Head of Pancreas (esp. if pain free) Appropriate treatment, e.g. ERCP, cholecystectomy, Whipples’

Pancreas Acute pancreatitis Presentation: Constant pain, vomiting, shock Causes: Gallstones, or alcohol Diagnosis: Serum amylase elevation (+/- LFTs), USS Complications: pseudocyst (collection in lesser sac), phlegmon (spreading diffuse inflammatory process with formation of purulent exudate – usually without bacterial infection), abscess

Michael Grant

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Small intestine Intestinal obstruction l May arise due to adhesions, hernia, tumour (usually a large bowel tumour that the small has become adherent to rather than primary) l Presentation: Colicky abdominal pain, vomiting, absolute constipation (no feaces or flatus) l XR: Valvulae conniventes, rigler’s sign l Treatment: l General principles: Cause, site, speed of onset, and completeness of obstruction determine definitive therapy: strangulation and large bowel obstruction require surgery; ileus and incomplete small bowel obstruction can be managed conserva- tively, at least initially l Immediate action: ‘Drip and suck’—NGT and IV fluids to rehydrate and correct electrolyte imbalance l Surgery: Strangulation needs emergency surgery, as does ‘closed loop obstruction’; Stents may be used for obstructing large bowel malignancies either in palliation Mesenteric Infarct l Sudden occlusion of small bowel arterial supply by thrombus or other embolus l Presentation: Classical clinical triad of acute severe abdominal pain; no abdominal signs; rapid hypovolaemia leading to shock +/- peritonitis, rigidity, silent bowel sounds l Treatment: resuscitate, operate ASAP l Treat in order 1 septic peritonitis and 2 prevent SIRS becoming multi-organ dysfunction syndrome (MODS), mediated by bacterial escape from dying bowel; Resuscitation with fluid, antibiotics (gentamicin + metronidazole) and, usually, heparin are required l If arteriography is done, thrombolytics may be infused locally via the catheter l At surgery dead bowel must be removed. Revascularization may be attempted on potentially viable bowel but it is a difficult process and often needs a 2nd laparotomy Infectious diarrhoea Crohn’s Disease Meckel’s Diverticulum l Rare, diverticulum of terminal ileum from embryonic remnants of vitelline duct containing gastric and/or pancreatic epithelium. There may be gastric acid secretion, causing GI pain & occult bleeding - can present like appendicitis l "2 inches long, within 2 feet of ileocecal valve, 2 times as common in males than females, 2% of population, 2x2=4% symptomatic, 2 types of ectopic tissue: gastric and pancreatic" l Meckel’s Scan - Technetium-99m radionucleotide scan looks for ectopic gastric mucosa; more sensitive and specific in children l Complications: Perforation, Ulceration, Littre’s hernias (hernial sacs containing strangulated Meckel’s) Large Bowel (+ App) Acute Appendicitis Acute Diverticulitis l Outpouching of the gut wall, usually at sites of entry of perforating arteries l Diverticulosis means that diverticula are present, and diverticular disease implies they are symptomatic l Maximal in (L) colon, usually in the Middle aged or elderly l Presentation: LIF pain, fever, tenderness, leukocytosis l CT abdomen is best to confirm acute diverticulitis and can identify extent/ complications l Enema or colonoscopy risk perforation in the acute setting. l Treatment: analgesia, NBM, IV fluids, antibiotics, CT-guided percutaneous drainage (if abscess) l Complications: Haemorrhage, perforation, fistula, abscesses, post-infective stricture -

Lower GI bleeding Causes: Diverticulum, colitis, Crohn’s, tumour l Present with Fresh Red Blood P/R l Tendency to be more conservative than with upper GI l Treatment: Resuscitate, consider transfusion Perforation l Causes: Diverticulum, colitis, l Presentation: sudden severe abdominal pain, rigidity from faecal peritonitis, Pyrexia, shock l AXR: Free gas on X-ray l Treatment: Resuscitate, ABx, prepare to operate Intestinal obstruction

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Michael Grant

Surgery: Page 4 of 85 Uncontrolled ulcerative colitis l Presents: bloody diarrhoea, pyrexia, leukocytosis and may develop toxic megacolon (acute form of colonic distension characterised by a very dilated colon – can progress to perforation) l Treatment: IV fluids, IV Steroids to management acute inflamm., surgery on failure Perintoneal cavity Peritonitis l Causes: Any perforation, pancreatitis, inflamm. In adjacent organ l Presentation: Abdominal pain, tenderness, guarding, silent abdomen, shock l Treatment: Rx of underlying condition Intra-abdominal abscess

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Acute Appendicitis

The appendix is a blind-ended tube connected to the cecum, from which it develops embryologically. It is a vermiform (worm-like) organ found at the origin of the teniae coli (the 3 longitudinal ribbons of smooth muscle on the outside of large colon). Incidence: l Most common surgical emergency (lifetime incidence = 6%) and accounts for 2% of all hospital admissions l Can occur at any age, though highest incidence is between 10–20yrs - but is rare before age 2 because the appendix is cone shaped with a larger lumen l Affects men more than woman but women have more operations for it Pathogenesis: l Gut organisms invade the appendix wall after lumen obstruction by: o Lymphoid hyperplasia o Faecolith (very impacted, potentially calcifed, faeces) o Filarial worms o Tumour o Foreign body o Secondary bacterial infection l This leads to oedema, ischaemic necrosis and perforation Symptoms/Signs: l Crampy colicky abdominal periumbilical pain o Usually becomes sharper and more localised pain to the RIF l Maximal tenderness of McBurneys point (two thirds of the way from umbilicus to ASIS) as inflammation moves to parietal peritoneum l Anorexia is an important feature; vomiting is rarely prominent — pain normally precedes vomiting in the surgical abdomen; likely to smell fetor l Constipation is usual but diarrhoea may also occur (esp. if pelvic appendix) l Urinary symptoms can occur with retrocecal appendix, direct inflammation spread to right ureter l Abdominal mass may be felt – important to establish if this is cancer or appendix mass l Specific signs: o Rovsing’s – pain in RIF increases on palpation of LIF o Psoas sign – pain on flexion of right hip, as retrocecal appendix contacts psoas o Obturator/Cope’s sign – pain on internal rotation and flexion of right hip, as appendix contacts obturator internus o Tender right sided PR examination – may be only sign on low-lying pelvic appendix Investigations: l Predominantly a clinical Diagnosis l WCC – left shift of white cells, neutrophil leucocytosis l URINE – rule out stone or UTI l PREGNANCY TEST l Scoring Systems - ALVARADO l USS Appendix – and consider ordering USS Pelvis/Renal tracts (rule out stones) l CT has high accuracy and useful in situations where the differential is unclear – but do not delay surgery for this if patient unstable Treatment: l If diagnosis unclear: Observation, analgesia, IV fluids and reassessment o Appendix mass can result from inflamed appendix wrapped by omentum; Some advocate early surgery but a trial of conservative management —NBM and antibiotics § If mass resolves, an interval appendicectomy (i.e. delayed) can be considered § If deterioration, then there is the possibility that an appendix abscess has form: surgical drainage by laparotomy or CT/US guided percutaneous is required Michael Grant

Surgery: Page 5 of 85 If diagnosis clear: o Prompt appendicectomy: § Lanz laparotomy (muscle sparing) § Grid iron laparotomy (muscle cutting, risk of hernia) § Laparoscopy - Has diagnostic and therapeutic advantages especially in women and the obese but not recommended in cases of suspected gangrenous perforation as the rate of abscess formation o ABx: Metronidazole 500mg/8h + cefuroxime 1.5g/8h, IV starting 1h pre-op, reduces wound infections § Give a longer course depending on severity, assessed visually: • Inflammed/injected – single dose • Purulent Exudate – 48hrs • Perforated – 5 day treatment § Any pus is sent for culture o If appendix normal (10-20% cases) - still removed and other causes excluded, e.g. Meckel’s Complications: l Short term o Post-op Ileus o Infection o Wound o Pelvic Abscess § Failure of Appendix stump ligation o Urinary retention, Pneumonia, DVT, PE l Longer term o Hernia (esp. if Grid Iron used) o Adhesions l Hospital stay o Uncomplicated 24-48hrs o Complicated - variable o Return to normal activities in 2-8 weeks depending on severity and post op complications

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Fluids and Electrolytes

Michael Grant

Surgery: Page 6 of 85

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Hernia

The definition of a hernia is “The abnormal protrusion of all or part of an organ through an opening in the cavity in which it is usually contained”. However, the main focus of our course in general surgery is the inguinal hernia. This is the protrusion of the contents of the abdominal cavity or pre-peritoneal fat through a defect in the inguinal area. These types of hernia can be best thought of as consisting of a neck, sac and contents. It is very common and 15% of males over the age of 75 will have had inguinal hernia repair, with a total lifetime incidence of up to 20%. They can be described as reducible (or irreducible if their contents cannot be pushed back into place), incarcerated (contents of sac are stuck inside by adhesions), obstructed (bowel contents are unable to pass through herniated segment) or strangulated (if ischaemia occurs). Reduction should be performed as a part of assessment, however it is important to avoid reduction en masse, in which a strangulated bowel and sac back into the abdominal cavity – still in a strangulated configuration. The inguinal canal is a 4cm passage than transverse the 4 muscle layers of the abdomen (made up of external oblique, internal oblique, transverus abdominus and rectus abdominus). It’s design allows for it to withstand changes in intra-abdominal pressure by using an oblque passage. It’s anterior wall protected by external oblique, poster wall by conjoint tendon that allow the canal to be flattened when these muscles are contracted. Superior wall (roof): Medial crus of aponeurosis of external oblique Musculoaponeurotic arches of internal oblique and transverse abdominal Transversalis fascia Anterior wall: aponeurosis of external oblique Fleshy part of internal oblique (lateral third of canal only)[3] superficial inguinal ring (medial third of canal only)[4]

(inguinal canal)

Posterior wall (floor): transversalis fascia conjoint tendon (inguinal falx,reflected part of inguinal ligament, medial third of canal only)[4] Deep inguinal ring (lateral third of canal only – lies just medial to position of femoral pulse, 40% of way from ASIS to pubic tubercle

Inferior wall: Inguinal ligament Lacunar ligament (medial third of canal only)[4] Iliopubic tract (lateral third of canal only)[3]

The classic description of the contents of spermatic cord in the male are: • 3 arteries: artery to vas deferens (or ductus deferens), testicular artery, cremasteric artery; • 3 fascial layers: external spermatic, cremasteric, and internal spermatic fascia; • 3 nerves: genital branch of the genitofemoral nerve (L1/2), sympathetic and visceral afferent fibres, ilioinguinal nerve (N.B. outside spermatic cord but travels next to it and only passes through the superficial ring before descending into the scrotum) Michael Grant

Surgery: Page 7 of 85 •

3 other structures: pampiniform plexus, vas deferens (ductus deferens), testicular lymphatics

Aetiology: • Patent processus vaginalis – embryonic failure of processus to fuse (most common cause, in 4% of all male infants; if found in female, rule out testicular feminisation) • Collagen disorder – in older adults, weaker collagen is produced • AAA – similar to above, if collagen is week in the aorta it may also be weak in the canal • Cigarette smoking and COPD – both from coughing and changes to collagen make-up • Ascites/Continuous Ambulatory Peritoneal Dialysis/ • Long term heavy work • Constipation/chronic urinary retention • African heritage (narrow, taller hip) Examination: 1. Ask patient to lay supine and inspect area for scars 2. Ask patient to cough and look to see if impulse is visible and increases size of lump 3. Ask if lump is visible and for patient to point out 4. Palpate and ask patient if they can reduce it (if not, rule out the possibility of a scrotal lump) 5. To determine if inguinal or femoral (more common in women): a. Inguinal – point of exit from abdomen will be above and medial to pubic tubercle b. Femoral – point of exit from abdomen will be below and lateral to pubic tubercle 6. If inguinal, to determine if direct or indirect (although not clinical relevant as management is the same): a. b.

Reduce the hernia and occlude the deep inguinal ring (1.5cm above femoral pulse at the mid-inguinal point) Ask patient to stand or cough – if hernia remains reduced then it is indirect (i.e. comes through the deep inguinal ring lateral to inf. Epigastric vessels) but if not then it is direct (i.e. bowel comes directly through hesselbach’s triangle – medial to inf. Epigastrics and lateral to rectus abdominus)

Pre-operative: • Is operation necessary? Older patients with no symptoms; does risk outweigh benefit? • Suitable for day surgery? Halves the cost of operation. • Explain procedure and alternatives; e.g. attempt at conservative management (weight loss and smoking cessation) • Counsel regarding risks: chronic pain, infection, bleeding, recurrence • Old advice was 4 weeks rest and 10 weeks convalescence but now, with modern mesh and laparoscopic techniques, can return to work and driving in 2 weeks or less if feeling up to it: o Walk from hour one o Encourage activity o Return to work 5 to 7 days o Avoid heavy lifting for one month Operative management • Herniotomy – only really suitable for paeds with patent processus vaginalus, and simply involves ligation of the proximal sac • Lichtenstein Tension-Free Hernia Repair o An open technique that involves dissecting into the inguinal canal, cutting open the peritoneum that forms the sac of the hernia, pushing the bowel contents back into the abdomen followed by ligating and/or removing the sac. o A polypropylene mesh is the stitched in to reinforce the deep inguinal ring to prevent recurrence • Laparoscopic (preferable in recurrent and bilateral hernias) both can similar steps but TAPP requires access into the peritoneum and thus has an additional incision that increases risk of visceral damage. o TAPP (transabdominal preperitoneal) repair o TEP (totally extraperitoneal) repair § Blunt dissection and insertion of ports into pre-peritoneal space § Complete dissection of pre-peritoneal space § Dissection of retro-pubic space § Dissection of hernia § Placement of mesh Complications: These are significant issue, however 95% have no early/immediate complications • Pain – especially chronic pain (44% of patients have long-term mild-moderate pain) • Recurrence • Haematoma • Infection • Urinary retention

Michael Grant

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Pre-operative assessments

Goals of pre-assessment: l Improve efficiency and enhance patient care l Identify potential problems l Plan appropriate investigations and referrals l Risk assessment l Enable liaison with surgical team l Patient education / counselling The toll of major surgery on the energy reserves of patients is considerable, i.e. equivalent to running a half-marathon or marathon for a fit personMajor surgery produces an inflammatory response that increases metabolic demands – increased heart rate is needed to accommodate oxygenation this so patients should be assessed for cardiac redundancy. Return to pre-op levels of fitness can take 3 to 6 months.! A thorough assessment will include: • History: o PC – Presentation, effect on general health, treatment o PMH - Cardiorespiratory conditions (surgery itself), reflux (airway), renal or hepatic (drug excretion), endocrine problems (stress response) § Previous Anaesthetic Hx - Anaesthetic Difficulties, Airway problems, PON&V, Adverse Reactions o Family Hx – unexplained ICU deaths, specific conditions o Exercise tolerance - Physical Activity Levels & Limiting Factors o Drug Hx § OCP/HRT – stop 4 weeks before (DVT/PE risk) § Aspirin – can probably be continued unless v. v. high risk § Beta-blockers – continue until day of surgery § Tricyclics – increase the action of adrenaline • Examination: o Full examination of systems o Airway assessment: § Predictors of difficulty with ventilation: • The Obese (body mass index > 26 kg/m2) • The Bearded • • §

• The Edentulous – no teeth Assessment of airway: • Look for Facial trauma/ Large incisors/ Beard/ Large tongue • Evaluate 3-3-2: Inter-incisor distance (3 fingers), Hyoidmental distance (3 fingers), thyroid to floor of mouth (2fingers) • Mallampati Grade! • •

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The Elderly (older than 55 y) – muscle wasting of face The Snorers

Obstruction – swelling, foreign body Neck movement – chin to chest, and absence ...