General surgery Flashcards
Preoperative preparations
Informed consent
Screening questionaire + regular medications
Consultation with anesthesia, cardiology
NBM after midnight
Prophylactic antibiotics: cefazolin + metronidazole
Consider DVT prophylaxis
Withhold aspirin for 1 wk prior to operation
Smoking cessation 6wks pre-op
Post-op Fever
POD 1-2
- Atelectasis
- Early wound infection
0 Aspiration pneumonitis
POD 3-7
- UTI
- Surgical and IV site infection
- Septic thrombophelbitis
- Bowel anastomosis leakage
POD 8+
- Intra-abdominal abcess
- DVT/PE
- Drug fever
6 W's Wind (pulmonary) Water (UTI) Wound Walk (DVT/PE) Wonder drugs Weins (thrombophlebitis)
Post-op drugs
6 A's Analgesia Anti-emetic Anti-coagulation Antibiotics Anxiolytics All other patietn meds
Post-op drugs
6 A's Analgesia Anti-emetic Anti-coagulation Antibiotics Anxiolytics All other patient meds
Post-op wound complications
Wound care
- Dressing removal POD 2-4
- leave uncovered if wound dry
- remove dressing if wet, signs of infection
- Bath from POD 2-3
- Suture removal POD 7-10 or - Suter removal delayed to POD 14 if elderly, steroid use, under tension
Drains
- Prevent fluid accumulation but can be sources of infection
- Removed if infected or drainage minimal <30-50mL/24hr
Surgical site infection
Bacteria: Staph aureus, E. coli, Enterococcus, Strept spp, Clostridium spp
Risk factors:
- Type of procedure
- Patient characteristics
- Other siurgical or progress factors
Presentation
- fever POD 3-6, strept and clostridium can present in 24h
- pain, erythema, induration, pus, warmth
Prophylaxis
- pre-op antibiotics: cefazolin, metronidazole, tobramycin (orthopaedics) 1hr prior to incision
- post-op antibiotics for 24hr
- normothermia
- hyperoxygenation FiO2 >80%
- sterile techniques
Treatment:
- Re-open incision, culture, pack
- Antibiotics and demarcation of erythema
- Debridement of non-viable tissue
Wound hemorrhage/hematoma
Inadequate surgical control of hemostasis.
Rx: pressure dressing, open drainage + wound packing for large hematoma
Seroma
Fluid collection other than pus or blood. It is secondary to transection of lymphatics and delays healing + increase risk of infection.
Rx: pressure dressing + needle drainage
Wound dehiscence
Disruption of fascial layer, suture tearing through the fascia. Present typically POD 1-3 with serosanguinous drainage +/- evisceration. No “healing ridge” at the wound edge.
Risk factors: increase IAP, hematoma, infection, poor blood supply, smoking, malnutrition, immunosuppression, steroids.
Rx: binder dressing on wound or operative closure.
Post-op urinary and renal complications
Urinary retention
- may occur after any operation with GA or spinal
- igher likelyhood in older males with BPH or those on anti-cholinergics
Oliguria/anuria
- most common due to pre-renal +/- ischemic ATN
- external fluid loss (hemorrhage, dehydration, diarrhea), internal fluid loss (third-space with bowel obstruction, pancreatitis)
Post-op respiratory complications
Atelectasis
- 90% of post-op pulmonary complications
- low grade fever on POD 1, tachycardia, crackles, decreased breath sounds, bronchial breathing
Prophylaxis
- Pre-op: smoking cessation >6wks
- Post-op: minimise respiratory depressant drugs, good pain control, incentive spirometry, deep breathing, chest physio, early ambulation
Pneumonia/pneumonitis
- secondary to aspiration of gastric content with GA and intubation
- productive cough, fever
- Prophylaxis: pre-op NG tube, rapid sequence anesthetic induction
- Rx: IV antibiotics
Pulmonary embolus
- sudden onset SOB, tachycardia, fever POD 7-10
- prophylaxis: SC heparin, TED stockings, aspirin
- Rx: IV heparin, long term warfarin for 3m
Pulmonary edema
- circulatory overload or LV failure
- SOB, crackles at bases, CXR abnormal
- Rx: morphine, nitrates, oxygen, sitting up
Respiratory failure
- dypnea, cyanosis, decrease sats
- Rx: ABCs, O2 +/- intubation, bronchodilators, diuretics, maintain adequate BP
Post-op cardiac complications
Common asshythmias: SVT, AF (secondary to fluid overload, PE, MI)
MI
- increased risked post-surgery
Hiatus hernia
Sliding hiatus hernia (Type I)
- herniation of both stomach and GE junction
- 90% of esophageal hernias
- risk fx: age, increased intra-abdominal pressure, smoking
- features: GRED
- investigations: barium swallow, endoscopy
- Rx: lifestyle (stop smoking, weight loss, no meals prior to sleeping, avoid alcohol), antacid, PPI, surgical if severe complications
Paraesophageal hiatus hernia (Type II)
- herniation of part of stomach with undisplaced GE junction
- features: asymptomatic, pressure sensation
- complications: hemorrhage, incarceration, stangulation, obstruction, ulcer
- Rx: surgery to prevent severe complications
Mixed hiatus hernia (Type III)
- combination of Types I and II
Type IV hernia
- herniation of other abdominal organs
Esophageal perforation
Causes
- iatrogenic: endoscopic, intubation, biopsy, NG tube
- barogenic: trauma, repeated forceful vomiting
- ingestion injury: batteries
- carcinoma
Features
- neck or chest pain
- fever tachycardia, hypotension, dyspnea, respiratory compromise
- pneumothorac, hematemesis
Treatment:
- NPO, vigorous fluid resuscitation, broadspectrum antibiotics
- surgical <24hr with primary closure
- surgical >24hr with diversion and delayed reconstruction
Esophageal cancer
Male > female, onset 50-60yrs, most common in lower esophageal.
Risk factors:
- SCC: 4 S’s (smoking, spirits, seeds, scalding), underlying esophageal disease (strictures, achalasia)
- Adenocarcinoma: Barrett’s eosphagus, smoking, obesity, GERD
Features:
- late presentation
- progressive dysphagia, odynophagia, regurgitation and aspiration
- hemetemesis, anemia, fistulas
- metastasis: trachea, recurrent laryngeal nerves, aortic, liver, lung, bone, lymph nodes
Investigations:
- Barium swallow
- Esophagoscopy
- CT chest
Thoracic outlet syndrome
Impingement of subclavian vessels and brachial plexus nerve trunk
Causes:
- congenital cervical rib
- trauma
- degenerative osteoporosis, arthritis
Features:
- neurogenic: ulnar and median nerve motor and sensory deficit
- arterial: fatige, weakness, coldness, pain
- venous: edema, venous distension
Rx:
- PT, posture and behaviour modification
- surgical removal of cervical rib
Tube thoracostomy
Insert at 4th or 5th intercostal space in ant axillary or mid-axillary line. Placed with underwater seal
Complications
- malposition
- bleeding
- local infection, empyema
- lung perforation
Peptic ulcer disease
Gastric ulcers
- require surgery if unresponsive to medical treatment (H. pylori eradication + PPI)
Duodenal ulcers
- typically on anterior surface on descending duodenum
- perforation presents with sudden acute pain onset, acute abdomen, ileus
- posterior penetration into pancreas creates pain radiating to back
- hemorrhage occurs with posterior penetration to the gastroduodenal artery, requires therapeutic endoscopy
Gastric carcinoma
More common in males and in Asian/Latina populations. Most commonly in 50-60 yr olds.
Risk factors:
- H. pylori
- HNPCC, HDGC
- smoking, alcohol, smoked foods
- pernicious anemia, gastric adeomatous polyps, hypertrophic gastropathy
- previous partial gastrectomy
Features:
- non-healing ulcer, lesion on greater curvature of stomach or cardia
- postprandial fullness, vague epigastric pain, anorexia, weight loss, burping, dyspepsia, dysphagia, hematemesis, fecal occult blood, melena, IDA
- signs of metastatic disease
= Virchow’s node: left supraclavicular node
= Blumer’s shelf: mass in pouch of Douglas
= Krukenberg tumour : metastasis to ovary
Staging I) mucosa + submucosa II) muscularis propria III) regional lymph nodes IV) distant metastasis
Treatment:
Surgical, chemotherapy, radiation
Bariatric surgery
Weight reduction surgery for those BMI >40 or BMI >35 with related comorbidity
Surgery:
- malabsorptive: decrease stomach size and bypass duodenum with Roux-en-Y
- restrictive: gastric banding
Gastric surgery complications
Alkaline reflux gastritis
- duodenal contents reflux into stomach
Afferent loop syndrome
- accumulation of bile and pancreatic secretions causes intermittent obstruction
Dumping syndrome
- hyperosmotic chyme released into small bowel, with fluid accumulation and jejunal distention
Blind loop syndrome
- bacterial overgrowth in afferent limb
Postcagotomy diarrhea
- bile salts in colon inhibit water reabsorption
Meckel’s diverticulum
Remnant of embryonic vitelline duct on border of ileum.
Features:
- only 2% symptomatic
- GI bleed by ectopic gastric mucosa, SBO, diverticulitis
Investigations
- Tec-99 (Meckel’s scan)
- AXR
Small intestine tumours
Risk factors:
- carsinogen exposure
- familial adenomatous polyposis, Peutz-Jegher syndrome, Gardner’s syndrome
- Crohn’s disease, celiac disease
Benign
- more common and usually asymptomatic
- polyps: adenomas, hamartomas, familial adenomatous polyposis, juvenile polyps
Malignant
- Adenocarcinoma: develops from polyps, predominance male 50-70yrs.
- Carcinoid: slow growing with <10% carcinoid syndrome (flushing, diarrhea, RHF), elevated 5-HIAA
- Lymphoma: usually NHL, increase risk wit autoimmune disease or immunosuppression
- Sarcoma
- Metastatic: from melanoma, breast, lung, ovary, colon, cervical cancer
Hernia terminology
Strangulated - compromised vascular supply
Incarcerated - irreducible
Richter’s hernia - only part of the bowel wall has herniated
Anatomical sites
- Groin
- Epigastric: linea alba
- Incisional
Groin hernias
Direct inguinal
- acquired weakness of transversalis fascia
- increased intra-abdominal pressure
- medial to inferior epigastric artery
Indirect inguinal
- most common in men and women
- congenital persistence of processus vaginalis in 20% of adults
- lateral to inferior epigastric artery and often descends into scotal sac/labia majorum
Femoral
- affects mostly females
- pregnancy, increased intrabdominal pressure
- into femoral canal, below inguinal ligament
Hesselbach’s triangle
Lateral - inferior epigastric artery
Inferior - inguinal ligament
Medial - lateral margin of rectus sheath
Inguinal ring
Superficial inguinal ring
- Opening: external abdominal aponeurosis, superior and lateral to pubic tubercle
- Medial border: medial crus of external abdominal aponeurosis
- Lateral border: lateral crus of external oblique aponeurosis
- Roof: intercrural fibres
Deep inguinal ring
- Opening: transversalis fascia, superior to mid-inguinal ligament
- Medial border: inferior epigastric vessels
- Superio-lateral borders: internal oblique and transversus abdominis muscles
- Inferior border: inguinal ligament