Download Investigation of the Surgical patient

Investigation of the Surgical
patient
M K ALAM
MS;FRCS
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.
Diagnosis
• History
• Clinical examination
• Investigations:
-Support clinical suspicion
-Refute clinical suspicion
-Risk to patient
-Cost
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
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)
Biochemical tests
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Na: 135-146 mmol/L ( water overload, NG asp., sepsis, vomiting)
K: 3.5- 5.5 mmol/L (changes- vulnerable to arrhythmias)
Urea: 2.6- 6.7 mmol/L ( dehydration, renal insufficiency)
Creatinine: 60-120 mmol/L (marker of renal disease)
Glucose: 3.9-5.6 mmol/L ( diabetes)
Total protein: 62-80 G/L
Albumin: 35-50G/L (nutritional assessment)
Bilirubin <17 mmol/L (jaundice)
ALP: 25-120 U/L
AST: 10-40 U/L
ALT: 5-30U/L
LDH: 49-195U/L
Creatinine phosphokinase: 24-195 U/L
Amylase <100 u/L
Microbiological investigations
• Urine (UTI), sputum, stool
• Hepatitis screening (B, C)
• Antibiotic sensitivity
Tumour markers
•
•
•
•
•
•
PSA- Prostate
CEA- Colorectal
α- fetoprotein (AFP)- Hepatocellular
β-hCG- Testicular, gestational
CA 19-9- Colorectal, pancreas
CA 125 - Ovarian
Imaging studies
• Plain x-ray- CXR, AXR, tomograms
Side effects: Induction of malignancy, genetic
mutation.
AXR (gallstone)
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
Gastrografin & Barium enema
Imaging studies
•
CT scan (oral, iv contrast): Widely used for abdomen, chest , brain, vascular and
urinary tract.
(anaphylactic reaction, renal injury, radiation)
•
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.
Intestinal ischemia
Intussusception
Lower GI bleeding Scan
Meckel's scan
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
Upper GI endoscopy & Colonoscopy
CBD stone extraction
ERCP (Stone CBD, Periampullary carcinoma)
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)
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
Screening
• Screening for malignant disease.(FOB,
mammography, PSA)
• Screening for surgical disease ( abdominal
aortic aneurysm)
Thank you!