Surgery Flashcards
What are the eight general indications for surgical prophylaxis?
Implants (joint or internal fixation) Prolonged surgery >2 hours Trauma surgery Revisional surgery Immunocompromised patient Extensive dissection required Intra-operative contamination Endocarditis (SBE)
What are the three most commonly used antibiotics for surgical prophylaxis?
Ancef/Cephazolin 2g q 4hr >120 kg use 3g
Clindamycin if PCN allergy 900mg q8hr
Vancomycin if MRSA 1g weight based sliding scale
What are the indications for ordering a chest X-ray?
Over the age of 40
Smoker
Any pulmonary/cardiac disease
What are the indications for ordering a preop EKG?
> 40 years
Any history of cardiac disease
What is the most common post operative time frame in which an MI occurs?
Day 3
How long should elective surgery be suspended if the patient has incurred an MI or CABG?
6 months
How are daily fluid inputs calculated? (not IV)
100 x first 10kg =1000 mL/day
10 x second 10kg
Remaining kg x 20
Example: 70kg patient requires: (100x10) +(10 x10) + (50 x 20) = 2500
How are daily IV fluid inputs per hour calculated?
The 421 rule!
first 10kg x4 =40
Second 10kg x 20
Remaining kg x 1
Ex 70 kg patient: 40+200+ 50 = 110 mL/hr
What is the perioperative order for diabetics?
NPO after midnight
Start D5W1/2NSS in AM
Accu-check
If insulin is controlled hold regular insulin and give half the NPH dose. Cover with sliding scale insulin.
If orally controlled, hold oral meds and cover with SSI
If diet controlled cover with SSI
What should always be obtained in a RA patient before surgery?
Cervical X-ray to look for atlantoaxial fusion.
What are the risks that a patient with long term corticosteroid use faces when undergoing surgery?
Adrenal function is supressed
These patients face risk of poor or delayed wound healing with decreased inflammatory process.
Risk of infection, low WBC may mask an infection.
What is the perioperative management for chronic steroid use?
Periop IV steroid supplementation
Hydrocortisone 100 mg IV given the night before surgery, immediately before surgery, and then q8h until posto-op stress is releived.
What is the perioperative management for patients at risk for gout?
Begin colchicine 0.6 mg PO daily 3-5 days pre-op and continue 1 week post-op.
What is the big concern with surgery on patients doing long term diuretics?
Low potassium levels
Patient is to continue use with 1/2 NSS at low rate.
When should aspirin be discontinued prior to surgery?
Seven days prior due to irreversibly binding platelets.
When should NSAIDs be discontinued prior to surgery?
3 days prior due to irreversibly binding platelets.
When should heparin be discontinued prior to surgery?
8 hours prior
Monitor PTT levels.
When should Coumadin be discontinued prior to surgery?
3-4 days (Monitor PT/INR)
What should the INR be for elective surgery?
<1.4
What should be done prior to surgery if the patients INR is >1.4?
A high INR means you are at risk for bleeding.
Transfuse fresh frozen plasma (FFP)
One unit of FFP will decrease the INR by approximately .2
Vitamin K can be given but its very slow.
If a patient undergoes surgery with a high INR what needs to be closely monitored?
Hgb and Hct
30 and 10
Which Hgb and Hct levels require a transfusion?
Surgical rule is the 30 10 rule in which Hgb should be 30 and Hct should be 10 for elective surgery.
If Hg: <8 or Hct <24 then a transfusion should be done.
What should be done if a patient is thrombocytopenic?
Order a six pack of platelets which is a concentration of six pooled platelet units.
consult hematology.
How are relaxed skin tension lines usually oriented?
Perpendicular to the long axis of the leg and foot
How should a skin incision be made in accordance to the relaxed skin tension lines?
Should be made parallel to the relaxed skin tension lines.
Perpendicular incisions are at risk for gapping due to increased transverse forces.
What is an anti-tension line incision?
S-shaped or Zig-zagged incision when the exposure that is needed cannot be made parallel to the relaxed skin tension lines,.
To close a lesion with minimal tension, what should the ratio of length to width be?
3:1 length to width.
How much lengthening can be achieved with a Z-plasty that has 60 degree angles?
75% lengthening!
To correct a skin contracture, how should a Z-plasty incision be oriented?
The central arm of the Z-should be parallel to the contracture.
To correct a 5th digit adductovarus rotation, how should the skin incision be oriented?
Distal medial to proximal lateral
“DMU”
What is the 4 steps to wound graft closure?
Direct closure
Graft
Local flap
Distant flap
What are the four stages of skin graft healing?
Plasmatic
Inosculation of blood vessels
Re-organization
Re-innervation
What are blair and humby knives?
These are knives used to harvest skin grafts
What is the most commonly used device to harvest skin grafts?
The dermatome.
What is the most common side effect of skin grafting?
Seroma/hematoma
How can hematomas/seromas be prevented in skin grafting?
Use mesh or pie crust graft and apply compressive dressings.
What are the advantages of using a split thickness graft?
Donor site heals spontaneously
May cover larger wounds.
What are the disadvantages of using a split thickness graft?
Grafts are fragile
Contraction of graft during healing
May be abnormally pigmented
What are the advantages of using a full thickness skin graft?
Minimal contraction of the graft
better appearance
What are the disadvantages of using a full thickness skin graft?
More difficult to take
Must close the donor site ({split thickness site self heals)
What is an advantage of using a muscle flap?
It brings immediate increased blood supply to the donor site.
What are the AO principles of internal fixation?
Anatomic articular reduction/adequate shaft reduction
Stable/biological fixation
Preservation of blood supply
Early ROM
What were the original AO principles published in 1958?
Anatomic reduction
Rigid internal fixation
Preservation of the blood supply
Early ROM
What are the steps to lag by technique?
Overdrill Underdrill Countersink Measure Tap Screw
How much of a screw thread should pass the far cortex in lag by technique?
One and a half threads
What is the purpose of tapping
Creates a path for screw threads
Why do you countersink for screws?
Prevents stress risers and soft tissue irritation
Provides compression from the land of the screw head.
What are the three sizes of the minifrag screws?
What type of screws are these?
1.5, 2.0, 2.7
These are all fully threaded cortical screws
What is the surgical screwdriver handle made of?
Pressed linen
What are the three differences between cortical and cancellous screws?
Cortical screws have a smaller pitch
Cortical screws have a smaller rake angle
Cortical screws have a smaller difference between thread diameter and core diameter.
What is unique about a malleolar scew?
4.5mm screw
Designed for fixation of the medial malleolus, partially threaded, same thread profile and pitch as a cortical screw.
Trephedine self cutting tip.
What type of screw is described as having a fluted tip?
Self tapping screws
What is the overdrill, underdrill, and countersink for a 1.5 mm screw?
Overdrill 1.5 mm
Underdrill 1.1 mm
Countersink 1.5 mm
What is the overdrill, underdrill, and countersink for a 2.0 mm screw?
Minifrag set
Overdrill 2.0
Underdrill 1.5
Countersink 2.0
What is the overdrill, underdrill and countersink for a 2.7mm screw?
Minifrag set
Overdril 2.7 mm
Underdrill 2.0 mm
Countersink 2.0 mm
What are the three small frag screw sizes?
What type of screws are in this set?
- 5 mm
- 0 mm fully threaded
- 0 mm partially threaded
(4. 0 for ankle gives both proximal and distal option)
What is the overdrill, underdrill, and countersink for the 3.5mm screw?
Small frag set
Overdrill: 3.5
Underdrill: 2.5
Countersink: 3.5
What is the overdrill, underdrill, and countersink for the fully threaded 4.0mm screw?
Small frag set
Overdrill: 4.0 mm
Underdrill: 2.5 mm
Countersink: 4.0
What are the four sizes of the large screw frag set?
- 5 mm
- 5 mm malleolar
- 5 mm partially threaded
- 5 mm fully threaded
What are the screw sizes found in the synthes modular hand screw system?
- 0
- 3
- 5
- 0
- 4
- 7
What are the Synthes cannulated screw sizes?
- 0
4. 0
What are the Smith and Nephew Cannulated Screw Sizes?
- 0
- 5
- 5
- 0
What are the steps for inserting a 4.0 mm cannulated screw?
Insert the 1.3 mm guide pin to the far cortex
Measure
Drill near cortex with a 4.0 mm cannulated bit
Drill the far cortex with a 2.7 mm cannulated bit
Tap
Countersink
Screw
What is a herbert screw?
A headless screw that can be inserted through articular cartilage.
There is a threaded portion proximally and distally with a smooth interpsace.
Proximal portion has a tighter pitch for compression.