FLS Flashcards
Benefits of Laparoscopy
- Faster recovery
- Cosmesis
- Less post operative pain
- Reduced adhesion
- Equivocal surgical results
Benefits of laparotomy
- Direct palpation of tissue
- Intuitive motion
- Easy abdominal access with unrestricted movement
- 3D
Surgeries that can use local anesthetic +/- mild sedation
- Diagnostic laparoscopy
- Bilateral tubal ligation
- Select inguinal hernia repair
Laparoscopic surgery physiology: CV
- Dec Cardiac output (Dec flow in IVC -> Dec preload)
- Dec splanchnic blood flow
- Dec cardiac output -> Increases afterload
- HR: Sinus tachycardia, PVC
- Inc lower extremity stasis and higher risk of VTE
Mechanism: Pressure/mechanical
Chemical = Hypercarbia
Trendelenburg
Laparoscopic surgery physiology: Pulmonary
Inc minute ventilation (Min Vent = TV x RR) to expel CO2
Inc peak airway pressure
Dec Functional residual capacity
Dec pulmonary compliance
Dec residual volume
Reduced diaphragmatic excursion - Upward displacement and stiffening of diaphragm
Decreased FRS and Reserve Volume for oxygenation = Atelectasis/VQ mismatch
CO2 accumulation
Greatest in first 15-20 minutes
Requires monitoring with end tidal CO2
Then reaches steady state
Hypotensive patient during laparoscopy
Desufflate
Check insufflator setting
Confirm adequate relaxation
Check intravascular volume status
Look for bleeding
Laparoscopy physiology: Renal
Oliguria - Renal compression
UOP is unreliable indicator of volume status
Intraoperative bolus can lead to cardiac failure, pulmonary edema
Chemical: Renin & ADH release - Reabsorption of Na, H2O, K excretion
Intraoperative oliguria self limiting after a few hours
Hypercarbia
CO2 from pneumoperitoneum absorbed in circulation
Hypercarbia effect on BP
Increase
Hypercarbia -> Sympathetic stimulation -> Increased SVR & Pulmonary vascular resistance -> Increased BP
Hypercarbia effect on pH
Acidemia
If CO2 not cleared by compensatory ventilation
Hypercarbia effect on cardiac output
Decreased
Hypercarbia -> Acidemia -> Decrease myocardial contractility -> Decreased Cardiac output
Hypercarbia effect on HR
Tachycardia, arrhythmia
Venous flow during pneumoperitoneum
Venous flow decreased 20-40%
Vagal stimulation
Stretching of peritoneum, pelvic organ manipulation, cervical stretching with manipulation = Bradycardia
Pneumoperitoneum (CO2)
Use warm CO2 - Improves patient temperature and post operative pain
Gas embolus 0.015%
Clinically insignificant gas more common
Hypotension, Tachycardia, JVD, mill-wheel mumur
CO2 embolus
Treatment:
1. Desufflate
2. Place in left lateral Trendelenburg (prevents embolus from entering right ventricular outflow tract)
3. Aspirate from central line
Contraindications to laparoscopy (Absolute)
Inability to tolerate laparoscopy
Hypovolemic shock
Lack of proper surgeon training
Lack of institutional support
Contraindications to laparoscopy (Relative)
Inability to tolerate general anesthesia
Long standing peritonitis
Large abdominal or pelvic mass
Massive incarcerated ventral or inguinal hernia
Severe cardiopulmonary disease
Acute glaucoma, retinal detachment, Inc ICP, VP shunt
Obesity and Laparoscopy
- Dec lung compliance
- Dec abdominal wall compliance = Higher insufflation pressure
- Heavy omentum putting pressure on diaphragm
- Thick subcutaneous tissue causes tunneling and prevents motion
- Higher conversion laparotomy, longer operating times, longer hospitalization
Laparoscopy in thin patients
Elevate abdominal wall
Open/Hassan, Optic trocar
Place Veress away from midline near costic margin
Ergonomic position
10-20 degrees below eye level
Patient position: Supine
Do not abduct arms >90 degrees: Prevent brachial plexus injury
Hands to void table break
Patient positioning: Tucked arms
Pelvic surgery
Patient positioning: Arms out
Upper abdominal surgery
Set up: Reverse trendelenburg
Foot board to prevent sliding
Belt across thighs to prevent knee buckling
Lithotomy
Allen stirrups > Candy canes (Femoral nerve hyperflexion)
Knees should be at level with abdomen to allow surgeon movement (upper abdominal/colon surgery)
Lateral decubitus surgery
Renal, Adrenal
Roll in axilla on dependent side - Prevent brachial plexus injury
Bean bag to hold patient up - Can cause pressure injury
Break bed to increase space between costal margin and iliac crest
Modified lateral decubitus
Splenectomy, Nephrectomy, Adrenalectomy
Allows rotation of operating table between lateral decubitus and supine
Allow for removal of large specimens
Easy conversion to laparotomy
Avoids flank incisions - Not tolerated well
Abdominal entry
- Blind trocar
- Open/ Hasson
- Opti view
- Varess
Blind trocar insertion contraindication (Relative)
- Previous abdominal surgery
- Previous intraabdominal inflammatory process
Blind trocar insertion contraindication (Absolute)
- Abdominal scar from prior open surgery in vicinity
- Placement of trocar through mesh
Diagnostic Laparoscopy
Reason: Uncertain etiology
3 port along the left abdomen (First - LUQ)
Laparoscopic Liver Surgery
Angled/ Flexible scope, may need ultrasound
Anterior abdominal wall surgery
30 degree scope
Appendicitis
Tuck both arms
Trendelenburg + Left tilt
Running small bowel
3 ports on left side of abdomen
Screen: Right shoulder & hip
Normal bowel: Ligament of Treitz -> Ileal cecal valve
SBO: Ileal cacal valve (decompressed) -> Ligament of Treitz
Trauma
Angled scope
Tuck both arms
Pelvic Surgery
Tucked arms
0 Degree scope
Mediastinum
Arms out
0 Degree scope
Set up: Retroperitoneal
Ports along costal margin (Access to kidney and adrenals)
Above Iliac bifurcation - Modified lateral decubitus
Mobilization of colon
Below Iliac bifurcation - Supine w/ Trendelenburg
Use electrocautery for biopsies?
No - makes patholgoy suboptimal
Large lesions
Incisional biopsy
Small lesions
Excisional biopsy
FNA
20-22 gauge needle
Core needle biopsy
14-18 gauge needle
Biopsy forcep
Small peritoneal implants (incisional or excisional)
Wedge biopsy
Scaple, Scissors, stapler (Incisional or excisional)
Liver biopsy
Most common: Core needle, Wedge resection
DO NOT biopsy vascular lesions
Cysts do not require biopsy
Ovary biopsy
Oopherectomy vs Wedge biopsy vs Forcep biopsy
Type of biopsy determined by menopausal status, concern for malignancy
Bowel biopsy
Excise small lesions - Close serosa with stitch
Laparoscopic suturing
Tapered needle > Cutting
Ports: 10 cm apart
Tension provided with continuous stitches (requires assistant) or locking
Sliding square knot
Useful for tissue under tension
Controls suture tightening
Intracorporeal knot tying
15 cm suture
Extracorporeal knot tying
Suture 75 cm +
Knot pusher
Roeder’s Knot (Endoloop)
End of blood vessel
Appendix
Fallopian tube
Cystic duct
Port sizes: Needles
8 mm port
Port sizes: Clips
8 mm , 10 mm
Good for tubular structure. Not good for bowel
Reusable - Requires reloading with each clip
Disposable - Can place multiple clips without reloading
Port sizes: Staples
12 mm port
Length: 30-60 mm
Places 2-3 rows of staples on each side
Staple sizes: White
Vascular: 2-2.5 mm
Staple sizes: Blue
GI tract: 3-3.5 mm
Staple sizes: Green
Distal stomach, Inflamed GI tract: 4-4.5 mm
Port site bleeding
Suture (Keith, suture passer, spinal needle)
Clip
Foley catheter (Temporary)
Peritoneal washing
100 mL NaCl
Wait 3-5 minutes before suction
Port site closure
Hernia risk <5%
Open
Laparoscopic assisted
Sole laparoscopic
Common causes of unrecognized bleeding
- Trocar injury
- Vessels/organs away from operative field (Liver, spleen)
- Venous bleeding tamponaded by pneumoneritoneum
Post operative resolution of pneumoperitoneum
Peak decrease within 30 minutes
Resolution within 3 hours
Post operative care: Nausea & Vomiting
Risk of aspiration
Wound breakdown
Failure of intraoperative hemostasis, tissue pedicle control
Post operative care: Pain
Referred pain to the shoulder - Conversion of CO2 to carbonic acid irritating diaphragm (1-3 days post op)
Prevention: Local anesthetic, lower insufflation pressure, evacuation of pneumoperitoneum, multimodal analgesia
Presentation of hollow viscus injury
Presents 1-7 days post surgery
Solid organ injury
Bleeding not appreciated during operation
Pancreas injured in splenectomy, left adrenalectomy, colon surgery — Pancreatic ascites, pseudocyst development
Bowel injury
0.0006 - 0.0016% (1 per 1000)
Vascular injury
0.00009 - 0.005% (5 per 1000)
Types of injuries during laparoscopic surgery
- Hollow viscus injury
- Solid organ injury
- Bowel
- Vascular
- Nerve
- Thermal burn
- Hernia
- Port site metastasis
Port site metastasis
1%
Types of gas supply
CO2, NO, Helium, Air, Argon
Nitrous oxide
Advantage: Less acid/base disturbance
Less post operative pain
Inc tolerance of pneumoperitoneum without general anesthesia
Cannot be used in cases with bowel perforation - Inc fire risk
Argon, Helium (Inert gas)
Advantage: Less acid/base disturbance
Disadvantage: Expensive
Inc extaperitoneal gas extavasation (Gas embolus)
Dec avalability
CO2 - Gas supply
Advantage: Dec combustion
High diffusion coefficient (20x O2) -> Soluble in blood -> Eliminated in alveoli
Dark or blurry image
Check fiberoptics - Hold lens up to light. Small black areas may present if damaged
Inspect lens
Moisture on eye piece
Defogging laparoscope
Wipe lens with defogging agent
Heated bath or scope warming device
Light source
300 W Xenon light source
Fire risk to sterile drapes
No CO2 (gas supply)
Confirm tank is full - May read empty if connected to central CO2 supply
Spare CO2 gasket available
Confirm for air leaks
No image
Ascertain monitor is plugged in
Impeded laparoscopic view/loss of working space
Check insufflator control panel
If measured pressure is < or = to preset pressure but flow is absent
Insufflator problem
- Wrong pressure for pneumoperitoneum
- Inadequate muscle relaxation
- Incorrect valve connection for insufflator
- Tubing obstruction
Low pressure, High flow
Check insufflator tubing is connected
Check all port valves are closed
Check for leaking CO2 from port sites
Check for distention of bowel or foley bag (Bowel/bladder injury)
Low pressure, absent flow
Power off
CO2 running low
Blank video screen
Disconnected power cord
Disconnected video cable
Disconnected light cable (scope or light source)
Blown light source bulb
Monopolar
Low -> High frequency
Required dispersive electrode (Bovie pad)
High resistance
Lateral spread
High energy requirement
Needs dry operative field
Cut
Low voltage
Tissue desiccation due to temperature rise -> Water evaporation = Desiccation
Inc Desiccation -> Inc tissue impedance until complete -> Current stops flowing due to high resistant -> Tissue turn brown, steam, bubbles
- Minimal lateral tissue damage
- Limited thermal coagulation
- Does not need direct contact
Coagulation
High voltage, intermittent wave form
Tissue coagulation due to tissue heating (>60C) -> Protein denaturing -> Cool 0> Reform in new pattern -> Tissue coagulation
Rapid surface heating, shallow depth of necrosis (fulguration)
Noncontact - Relies on sparking between device and tissue
Blend
Adds hemostatic effect to cutting
Current Diversion
Current passes through unintentional tissue due to path of least resistance
Fix: Insulate scope
Use low voltage and power
Activate when close to target
Use bipolar
Do not use hybrid ports (plastic/metal)
Capacitive coupling
Transfer of current from active electrode (scope, port) —> Insulator —> Passive electrode (capacitor)
Needs 2 conductors to be separated by insulator
Metal object holds charge until it can release on another object causing inadvertent injury
Example: Metal port with plastic screw
Fix: Using plastic ports or all metal trocars
Direct coupling
Transfer of current from active electrode to metal
Narrow return circuit
Current passes through ligated tissue in logarithmic fashion -> Excessive tissue heating -> Delayed perforation
If the largest part of tissue is touches, the most narrow region with be affected
Bipolar
Low resistance circuit
Tissue placed between both electrodes
Does not need dispersive electrode (bovie pad)
Less lateral spread
Lower energy requirement
Works in wet environment
Disadvantage of Bipolar
Inadvertent thermal injury to adjacent organs
Inadvertent cutting of patent vessels before adequate sealing
Device will not work if metal within jaws (staples, clips)
Disadvantage of Monopolar
Direct coupling
Capacitive coupling
Narrow return circuit
Port placement if prior surgery, umbilical hernia, mesh
Palmar point
Laparoscopy in pregnancy
2nd trimester
Bleeding staple line after use on omentum
Staples too large
Repairing enterotomy
Leave long tails for stay sutures
Absorbable sutures
Serosal bleeding
Oversew
Ultrasonic energy (Harmonic)
Mechanical energy
- Electric energy -> High frequency vibration (50,000 Hz)
- Passive blade (hold tissue) and active blade (transfers heat)
- Higher power = more cutting
- Lower power = more coagulation
