1. Investigation of the Surgical patient
M K ALAM MS;FRCS

2. Objectives At the end of this presentation students will be able to:
Identify the need for establishing diagnosis.
Describe the whole spectrum of available investigations.
Choose relevant investigations and justify their use.
Understand the side effects and complications of some investigation.
Identify need for assessing physiological status.
Understand the need for screening common asymptomatic disorders.

3. Establish diagnosis History Clinical examination Investigations:
-Support clinical suspicion
-Refute clinical suspicion
-Risk to patient
-Cost

4. Other aims of investigation
Assess physiological impairment for risk to surgical treatment.
Example: Cardiac, renal respiratory diseases
Screen for common asymptomatic disorders.
Example: Diabetes, coronary artery disorders, hypertension

5. Hematological investigations
FBC or CBC: Anemia (low Hb.), MCV, MCHC (normocytic, microcytic), leukocytosis (infection)
Platelet count: Thrombocytopenia ( drug- heparin, ITP, autoimmune), Thrombocytosis ( post-splenectomy)
Coagulation profile: PT, INR, APTT (disordered in patients of jaundice, bleeding, anticoagulant, antiplatelet medications)

6. Biochemical tests
Na: mmol/L ( water overload, NG asp., sepsis, vomiting)
K: mmol/L (changes- vulnerable to arrhythmias)
Urea: mmol/L ( dehydration, renal insufficiency)
Creatinine: mmol/L (marker of renal disease)
Glucose: mmol/L ( diabetes)
Total protein: G/L
Albumin: 35-50G/L (nutritional assessment)
Bilirubin <17 mmol/L (jaundice)
ALP: U/L
AST: U/L
ALT: 5-30U/L
LDH: U/L
Creatinine phosphokinase: U/L
Amylase <100 u/L

7. Microbiological investigations
Urine (UTI), sputum, stool
Hepatitis screening (B, C)
Antibiotic sensitivity

8. Tumour markers PSA- Prostate CEA- Colorectal
α- fetoprotein (AFP)- Hepatocellular
β-hCG- Testicular, gestational
CA Colorectal, pancreas
CA Ovarian

9. Imaging studies Plain x-ray- CXR, AXR, tomograms
Side effects: Induction of malignancy, genetic mutation.

11. AXR (gallstone)

12. Imaging studies
Contrast studies- gastrografin swallow, barium meal, barium enema.
Visualize GI tract
Single contrast, double contrast
Inferior to endoscopy
Contraindicated if bowel perforation suspected

13. Gastrografin & Barium enema

14. Imaging studies
CT scan (oral, iv contrast): Widely used for abdomen, chest , brain, vascular and urinary tract.
(anaphylactic reaction, renal injury, radiation)
CXR millisieverts CT abdomen & pelvis- 9.5 ms.
Ultrasound: Safe, low cost. Operator dependent Investigation of first choice for biliary disease and gynaecology.
MRI: Good images of soft tissue (better than CT), blood vessel (MRI angiogram) No radiation, no known deleterious effect Slow and expensive.
Isotope scan: More information about function than structure I131,Tc99, I123, Ga67, Th201- incorporated into other molecule to localize target organ. Detected by gamma camera Bone metastasis, renal function, foci of infection, GI bleeding, infarction of myocardium, sentinel node detection
PET scan: Expensive. Brain physiology, tumour detection , cardiac physiology.

15. Intestinal ischemia

16. Intussusception

17. Lower GI bleeding Scan

18. Meckel's scan

20. Endoscopy
Precise diagnosis of GI, pancreatico-biliary, bronchus, urinary tract pathology.
Perform cytology/ biopsy.
Minimally invasive therapy- laparoscopy, arthroscopy, ERCP.
Disadvantages: Unpleasant, uncomfortable (sedation/ anesthesia)
Complications: Infection, perforation, aspiration, bleeding, cardiac arrhythmias, respiratory arrest

21. Upper GI endoscopy & Colonoscopy Carcinoma- Stomach & rectum

22. ERCP (Stone CBD, Periampullary carcinoma)

23. CBD stone extraction

24. Tissue sampling Body fluids- pleura, peritoneum, sputum , urine.
Smears, brush cytology
FNAC ( insitu vs invasive, follicular adenoma vs carcinoma)
Core biopsy
Open biopsy
Frozen section biopsy: (biopsy frozen in liquid nitrogen, sliced, stained and reported in minutes)

25. Function tests
Cardiac evaluation: ECG, Thallium scan, echocardiography
Respiratory function: ABG ( risk pCO2 > 45 mmHg) FVC & FEV1 ( risk- < 70% of predicted)
Renal function
Endocrine function

26. Screening Screening for malignant disease.(FOB, mammography, PSA)
Screening for surgical diseases ( abdominal aortic aneurysm)

27. Thank you!