Pre And Perioperative Flashcards
unfrictioneted heparin overdose
Give protamine sulphate
DVT complication develops in
The following surgical patients are at increased risk of deep vein thrombosis:
Surgery greater than 90 minutes at any site or greater than 60 minutes if the procedure involves the lower limbs or pelvis
Acute admissions with inflammatory process involving the abdominal cavity
Expected significant reduction in mobility
Age over 60 years
Known malignancy
Thrombophilia
Previous thrombosis
BMI >30
Taking hormone replacement therapy or the contraceptive pill
Varicose veins with phlebitis
Dehydration diagnosis
Diagnosing dehydration can be complicated, laboratory features include:
Hypernatraemia
Rising haematocrit
.Metabolic acidosis
Rising lactate
Increased serum urea to creatinine ratio
Urinary sodium <20 mmol/litre
Urine osmolality approaching 1200mosmol/k
Postoperative optimi urine output is
0,5ml/kg/hr
Postoperative oliguria is
<30ml/hr for 4 consecutive hours
Bupivacaine and lidocaine dosage with and without adrenaline
Bupivcaine without is 2mg/kg and with is 3mg/kg
Lidocaine without is 3mg/kg ND with is 7mg/kg
Amaximum dose of lidocaine in adults is
200mg
Thus if according to weight the dosage is more than we will not increase it to more than 200
CABG is preferred in
The guidelines state that CABG is the preferred treatment in high-risk patients with severe ventricular dysfunction or diabetes mellitus.
which is the excellent conduit for coronary artery bypass
internal mammary artery is an excellent conduit for coronary artery bypass
Indications for CABG
Left main stem stenosis or equivalent (proximal LAD and proximal circumflex)
Triple vessel disease
Diffuse disease unsuitable for PCI
Incisions for CABG
Midline sternotomy or left sub mammary incision
What happens when both IMA are used for bypass
Use of both is associated with increased risk of sternal wound dehiscence
Perioperative risk for CABG is calculated by
Perioperative risk is quantified using the Parsonnet and Euroscores and unit outcomes are audited using this data.
Among all structure which arebehind sternum, which needs to be divided
The interclavicular ligament lies at the upper end of a median sternotomy and is routinely divided to provide access
fibrocartilage
risk factors for recurrent Venous thromboembolism
SIGN also state that the following are risk factors for recurrent VTE:
previous unprovoked VTE
male sex
obesity
thrombophilias
Which antipsychotics causes VTE
Olanzapine
Drugs causing VTE
Medication
combined oral contraceptive pill: 3rd generation more than 2nd generation
hormone replacement therapy
raloxifene and tamoxifen
antipsychotics (especially olanzapine) have recently been shown to be a risk factor
Swinging pyrexia in
Anastomotic leak
Central line sepsis
Groin lines and those for TPN have the highest risk of central lin sepiai
Most common site of aortic dissection
Ascending aorta
Stanford classification of Aortic dissection
Type A: Proximal to subclavian
Type B: Distal to subclavian
Rx of aortic dissection
Proximal (Type A) lesions are usually treated surgically, type B lesions are usually managed non operatively
a popular choice drug in managing complex peri anal Crohns
Infliximab
Imatinib used in
Gastrointestinal stromal tumours
Chronic myeloid leukaemia
Bevacizumab is used for
Colorectal cancer
Renal
Glioblastoma
Trastuzumab is used in
Breast cancer with HER receptor
Basiliximab is used in patients with
Renal transplants
Cetuximab is used in
EGF positive colorectal cancers as it is EGF inhibitor
Which biological agents are used in
Crohns disease
Rheumatoid disease
Adalimumab
Infliximab
Etanercept
Gastrointestinal stromal tumours are treated by which biological agents
Imatinib
Some procedures require special preparation:
Thyroid surgery
Parathyroid surgery
Sentinel node biopsy
Surgery involving the thoracic duct;
Pheochromocytoma surgery
Surgery for carcinoid tumours
Colorectal cases
Thyrotoxicosis
Thyroid surgery; vocal cord check.
Parathyroid surgery; consider methylene blue to identify gland.
Sentinel node biopsy; radioactive marker/ patent blue dye.
Surgery involving the thoracic duct; consider administration of cream.
Pheochromocytoma surgery; will need alpha and beta blockade.
Surgery for carcinoid tumours; will need covering with octreotide.
Colorectal cases; bowel preparation (especially left sided surgery)
Thyrotoxicosis; lugols iodine/ medical therapy.
Which hypoglycemic has to be stopped pre operatively
Met forming 48 hours prior
Preoperative insulin infusion in type 1 diabetic
Insulin should not be stopped in patients with type 1 diabetes and omission of more than one meal will usually require a variable rate insulin infusion
Paste like anesthetic used for ENT surgeriew
Cocaine
Drug interactions of lidocaine
Beta blockers, ciprofloxacin, phenytoin
Cocaine use percentage
4 and 10 %
Which anesthetic is used for topical wound infiltration at the conclusion of surgical procedures
Bupivcaine bcx of its long duration of action
Which anesthetic contra indicated in regional blockage in case the tourniquet fails6
Bupivcaine as it’s cardiotoxic
Drug of choice in bier block
Prilocaine
Acidic environment and local anesthetic
They don’t work as acidic environment disintegrate the drug
Max dose of
Lignocaine 1% plain -
Lignocaine 1% with 1 in 200,000 adrenaline -
Bupivacaine 0.5%
3mg/ Kg - 200mg (20ml)
7mg/Kg - 500mg (50ml)
2mg/kg- 150mg (30ml)
Adrenaline with local anesthetic is contraindicated in patients
contra indicated in patients taking MAOI’s or tricyclic antidepressants.
Heparin dosage in CABG
A dose of 30,000 units is given just prior to going on cardiopulmonary bypass.
Which kind of heparin to be given before surgery
Unfractionated heparin
Drugs need to be stopped prior to surgery and before how long
oral contraceptive pill for a month,
aspirin or clopidogrel for 2 weeks before surgery
oral contraceptive pills should be stopped how long before surgery
oral contraceptive pill for a month,
Aspirin or clopidogrel should be stopped how long prior to surgery
2 weeks
INRrange for open vs jnvasive procedures
Open: <1.2
Invasive: <1.5
Fractionated Heparin inhibits only
Inhibits only factor Xa
During infractionated heparin what we should check
Un fractionated heparin
Heparin inhibits which factors
7,9,10,11 &12.
Tinzapin and
Enoxaprin dosage
Both are Frac Heparin
Once daily
Twice daily
Negative acute phase protein
Albumin
it’s increasing Levels indicate good recovery
Malignant hyperpyrexia is treated by
Dantrolene sodium Img/kg IV upto 10mg/kg max dose
Why Na avoided in old adults
risk of hyperchloraemic acidosis
Fluid of ccrystalloid in old adults
Ringer’s lactate or Hartmann’s
Na in old adults can be given only when
patient is vomiting or has gastric drainage.
Fluid of choice in Sodium losses secondary to diuretics.
Hartmann solution
When 5% dextrose as well as colloid should be given.
critically ill patient who is unable to excrete Na or H20 leading to a 5% risk of interstitial oedema
Adult requirement daily for fluid
Na
K
50-100mmol /day
40-80 mmol /day
5% dextrose as resuscitation or maintenance fluid
Use 4%/0.18% dextrose saline or 5% dextrose in maintenance fluids
IV fluid resuscitation Criteria
use crystalloids that contain sodium in the range 130-154 mmol/l, with a bolus of 500 ml over less than 15 minutes
Mackler triad
The Mackler triad for Boerhaave syndrome: vomiting, thoracic pain, subcutaneous emphysema. It typically presents in middle aged men with a background of alcohol abuse.
Oral fluid prior elective surgery
stop
Solid 6 hours pre-operatively
Fluid 2 hours
IV cannula for any long term therapy like AML
Groshong lines and Hickman lines
There can’t be given through peripheral line
inotropes and irritant drugs such as TPN
No use of central line in rapid rates of infusion due to
lumens are relatively narrow and thus they do not allow particularly rapid rates of infusion.
Groshong and Hickman lines are inserted in
Internal jugular vein
Good site for venous cut dowm
Long saphenous
Antecubital ( prefer median basilic vein)
Central venous acces is mostly through 2hich veins
Subclavian and
Internal jugular vein
Diff between low molecular and unfractionated heparin
Low molecular: no measurement of APTT needed
Unfractionated: Measurement of APTT needed
Lignocaine is used as
Local Anesthetic
Class IB antiarrythmic
Which type of Wound healing is affected in diabetes
Migration of neutrophils into wound
Mnemonic to remember factors affecting wound healing:
DID NOT HEAL
D iabetes
I nfection, irradiation
D rugs eg steroids, chemotherapy
N utritional deficiencies (vitamin A, C & zinc, manganese), Neoplasia
O bject (foreign material)
T issue necrosis
H ypoxia
E xcess tension on wound
A nother wound
L ow temperature, Liver jaundice
Diff between hypertrophic and keloid scars
Hypertrophic: don’t grow outside it’s boundary
Keloid: Grow outside it’s boundary
Delayed primary closure versus secondary
In delayed the wound is sutured back before formation of granulation tissue
In secondary it is formed after formation of granulation tissue.
Preferred test for aortic dissection is
CT angiography of chest
aortic dissection has which kind of murmur
Loud diastolic murmur which is of aortic regurgitation
Diagnosis of Boerhaaves syndrome is by
CT contrast swallow
Diagnosis of Peptic ulcer perforation
Erect chest x-ray which may show a small amount of free intra-abdominal air (very large amounts of air are more typically associated with colonic perforation).
Main peri-operative concern in people with aortic Stenosis
They can’t increase their cardiac output
investigation of choice for aortic stenosis
trans thoracic echocardiography is the
Meangradient in Severe aortic stenosis
> 40mmhg
EcG finding in proximal aortic dissection
ST-segment elevation in leads II, III, and aVF
bez mostly right cardiac ostia is involved
If ECG ShowII, III and aVF ST elevation then D/D willbe
1 Inf wall MI
2 Ascending Aortic dissection
Look for other-symptom tearing chestpain, pericardial effusion, carotid dissection and absent subclavian pulse in aortic dissection
Symptoms of aortic dissection
tearing chestpain, pericardial effusion, carotid dissection and absent subclavian pulse in aortic dissection
Test of choic ein warfarin and heparin
War: PT
Heparin: APTT
Low molecular weight heparin is
Fractionated
Fractionated heparin is
Has long half life
Decrease HIT
Stop heparin howmany hour ago to surgery
6 hours
Diabetes Rx of type I and II prior tosurgery
Type I: Insulin sliding scale
Type II: Waitand watch policy with regular blood glucose levels measurement
methylene blue to identify
Parathyroid for surgery
Sentinel node biopsy check before surgery through
patent blue dye
What to do before
Pheochromocytoma surgery;
Give first alpha then beta blockade
Drug for carcinoid tumor
Octreotide
Most commen injury 2° central line is
Tension Pneumothorax
It exacerbates whon Positive pressure ventilation is given & causes hemodynamic instability
Ifextremity and anesthetic required then
Don’t use Adrenaline
If Zadek procedure thenwhich anesthetic
Ring block with 1% lignocaine alone
Dosage of local anaesthetic agents
0.5% = 5 mg/ml
1% =10mg/ml
2% =20mg/ml,
Post operative use of local analgesia
Analgesia (eg epidural for laparotomy) • Respiratory function (allows deep inspiration and pain-free chest physiotherapy)
Topical Anesthetics
EMLA cream before cannulation in children
Lidocaine gel before urethral catheterisation
Xylocaine spray before gastroscopy
Brachial plexus blocks may be performed at different levels:
Interscalene block (trunks)
Supra-/infraclavicular block (divisions) Axillary block (cords)
Femoralblock
The femoral nerve lies at a point that is 1 cmlateral to the pulsation of the femoral artery as it exits from under the inguinal ligament and 2 cmdistal to the ligament.
Femoralblock is suitable for
This is suitable for analgesia covering the anterior thigh, knee and femur.
Intercostal block
Posterior angle of the rib at the posterior axillary line and insert the needle just below the edge of the rib
COLLOIDS example
:
Human albumin
Gelofusine
Dextrose 40
Hydroxyethyl starch
Perianal abscesswound closure thorugh
S3condary intention
ERCP preparation
Clotting, antibiotics, Vitamin K if jaundiced
Diagnostic OGD preparation
Nil by mouth for 6 hours
Flexible sigmoidoscopy preparation
Phosphate enema 30 minutes pre procedure
Colonoscopy preparation
Check U+E and if normal, prescribe oral purgatives e.g. picolax( oral Picosulphate 1 day prior)
Rx of keloid scar
Injection of Triamnicilone
Amino Ester vs amino amide anesthetics
AE: Procaine and Benzocaine
AA: All other Anesthetics
Which anesthetics are amino Ester and not amino aside type
Procaine and Benzocaine
Lignocaine MOA
Lignocaine blocks sodium channels.
If first pain then anesthesia is due to which drug
Lignocain3 as it first enhances then suppresses nervous system
Drug wh8ch should be stopped prior to colonoscopy
Ferrous sulphate
7 days prior
To diagnose Fe defi anemia gut, how to prepare
Stop ferrous sulphate 7 days pre procedure and administer oral purgative1 day prior
What blood test to be done before colonoscopy
UCE as purgative e can cause electrolyte imbalance
Anesthetic for bier block
Only 1% prilocaine without adrenaline
LMWH and renal function
Don’t give if impaired renal function
Rev3rsal of Dabigatran
Idarucizumab
Continues infusion of which heparin
Unfractionated
Which anticoagulant is used as a prophylaxis in hip and knee surgery.
Dabigatran
Atrop8ne is used to treat
low heart rate (bradycardia), reduce salivation and bronchial secretions before surgery or as an antidote for overdose of cholinergic drugs or mushroom poisoning
Alcoholic+acute pancreatitis+clinically dehydrated with normal renal function and UCE
What fluid to give
Harrtmann
sodium losses secondary to diuretics
Which fluid to give
Hartmann
CHAD Score is used for
The CHADS score assesses whether a patient should be warfarinised if they have atrial fibrillation
Which graft shows late stenosis in CABG
Saphenous vein
Lateral chest radiograph
to assess distance between front of right ventricle and back of sternum
- Aspirin: cyclo-oxygenase (COX) inhibitor
- Clopidogrel
- Abciximab(andsimilar drugs)
- inhibits thromboxane A2 production fromarachidonic acid .
- platelet ADP-receptor antagonist .
- infusible glycoprotein (GP) IIb and IIIa inhibitors
Antibiotic prophylaxis b3fore CABG
Cefuroxime IVin 3 doses is the most commonly used antibiotic.
The aims of cardioplegia are
Cardioplegia : •Maintenanceofastillsurgicalfield •Maintenanceofmyocardialenergystoresbyabolitionofmyocardialcontraction
procedures to assess distance between front of right ventricle and back of sternum
Cardioplegia aim
•Maintenance of a still surgical field •Maintenance of myocardial energy stores by abolition of myocardial contraction.
Physiological condition for CAB
Non pulsation flow to get mean perfusion pressure of 6mmHg
Systemic cooling 30 to 32°C
Thromboprophylaxis in children with risk criteria
None
What to use to prevent clotting prior to surgery in a patient with hepatic dysfunction
Ffp
Rich source of Factor VIII and fibrinogen
Cryoprecipitate
SAG-Mannitol Blood
Removal of all plasma from a blood unit and substitution with:
Sodium chloride
Adenine
Anhydrous glucose
Mannitol
