FLS LATEST 2026 STUDY GUIDE QUESTIONS AND ANSWERS
GRADED A+
✔✔Troubleshooting: actual pressure in abdomen is higher than your set pressure flow
rate - ✔✔-check actual and set pressure of pneumoperitoneum and make sure it is
correct
-check status of relaxation of the patient (look for intraabdominal muscle contractions or
firmness of the abdomen which is different than anesthesia check for neuromuscular
twitch which has to do with the diaphragm relaxing not the abdomen)
-check to see if the valve connected to insufflator tubing is on/open
-check to make sure insufflator tubing is not kinked or someone standing on it
✔✔Troubleshooting: actual pressure in the abdomen is lower than your set pressure
flow rate and your flow states that you are on high flow - ✔✔-check insufflator tubing
and make sure tubing is connected to the insufflator and port
-check all ports and make sure the valves are closed
-check ports for leaking CO2 (e.g. skin/fascia incision to big and CO2 is leaking)
-check for distention of bowel and bladder catheter as CO2 can escape into other
hollow organs
✔✔Troubleshooting: actual pressure in the abdomen is lower than your set pressure
flow rate but your flow states that you have no flow - ✔✔-ensure power is on
-check gas tank level
-check CO2 gasket to ensure no leak or damage
✔✔what are the two options for delivering radiofrequency electricity? - ✔✔monopolar vs
bipolar
✔✔what type of circuit does monopolar use? - ✔✔electrosurgical unit (ESU) that
converts low frequency current from a wall source to high frequency current in order to
cut and coagulate; everything is delivered and received through electrodes
-i.e. high frequency goes through metal portion of laparoscopic instrument --> through
the tissue --> to the dispersive electrodes connected to the generator (i.e. grounding
pad)
✔✔how does tissue coagulation occur with monopolar? (describe process) - ✔✔-tissue
heating (temps > 60 Celsius) causes protein denaturation. As tissue cools, bonds
reform in a haphazard fashion leading to tissue coagulation.
-as tissue heating is occurring, water evaporates from tissue causing desiccation and
the tissue impedance (resistance) increases until current eventually stops flowing due to
the very high resistance.
-Clinically tissue will turn brown, bubble, and steam
✔✔definition of hemostasis - ✔✔fibrous binding of dehydrated/denatured of vessel
endothelium
,✔✔at what temp does internal water molecules vaporize and explode? - ✔✔100
degrees Celcius
✔✔how does current density relate to power and tissue resistance? - ✔✔-current
density is directly proportional to applied power
-current density is inversely proportional to tissue resistance
✔✔formula for tissue heating - ✔✔(current density)^2
= (current/area)^2
✔✔Formula for current density - ✔✔current (amps) / area (cm2)
-therefore if area is large (i.e large area of dispersive electrode like the grounding pad
on the patient), the less current density there is and thus the less the current heat and
vice versa
✔✔On what areas should the grounding pad not be placed on a patient and why? - ✔✔-
hairy skin, previous scars, metal implants
-increases risk if burn to patient
✔✔3 basic modes of operation on monopolar instruments (describe them) - ✔✔-Cut:
unmodulated waveform, low voltage; heats tissue quickly by causing cell water to steam
and then explode. Causes less thermal spread but poor coagulation. Electrode should
not contact tissue directly.
-Coag: intermittent waveform, high voltage; rapid surface heating causing a superficial
eschar formation and shallow depth of necrosis. (fulguration). Allows heat to be more
widely dispersed so cutting does not happen; can do noncontact mode and arc heat
from electrode to tissue
-Blend: mixes both wave forms allowing surgeon better control of desired tissue effect
✔✔Hazards of monopolar - ✔✔1. current diversion where current may through
unintentional pathways because it follows the path of least resistance
2. capacitive coupling: when the electrode (metal thing with current
like monopolar scissors) touches something it wasn't supposed to (e.g. suction irrigator
or another instrument etc), that passive instrument will serve as a capacitor and store
the charge and potentially unintentionally burn something else
3. excessive tissue heating can occur when trying to apply current to ligated tissue
(ligated tissue = small area = big current density = excess heat)
Ex: apply heat to ligated tissue (ex: appendiceal stump) can result in delayed
appendiceal blow out
✔✔what structures should you avoid when using monopolar? - ✔✔vascular structures,
ureter, nerves
, ✔✔How do you minimize risk of inadvertent tissue injury with monopolar? - ✔✔-inspect
insulation carefully
-use lowest possible power setting
-use lowest voltage waveform (pure cut or continuous low voltage waveform)
-use brief intermittent activation instead of prolonged activation
-don't activate unless in proximity of target tissue
-don't activate in proximity or direct contact with another instrument
-use bipolar if able
-don't use hybrid ports that mix metal and plastic
✔✔how does tissue coagulation occur with bipolar? (describe process) - ✔✔-tissue is
placed directly between 2 electrodes and current is only able to flow between these 2
(no need for grounding pad); current flows through much smaller amount tissue
-controlled delivery and high pressure from grasping tissue causing denaturation of
collagen within tissue wall
✔✔Difference between monopolar and bipolar - ✔✔-lower energy requirement and thus
less tissue necrosis compared to monopolar
-less lateral thermal spread given lower energy used
✔✔max diameter of vessel that bipolar can seal - ✔✔7mm
✔✔Hazards of bipolar - ✔✔-inadvertent damage to adjacent organs can occur
-if instrument has a cutting blade and you cut prior to adequate sealing, bleeding can
occur
-need to complete entire activation cycle before cutting
-will not work if metal is within the jaws (e.g. surgical staples)
✔✔what is ultrasonic energy? how does it work? - ✔✔-relies on mechanical energy and
tissue heating is generated by converting electric energy to high frequency ultrasonic
vibration (i.e. piezoelectric transducer) with minimal heat being transferred to passive
jaw
-50,000x/second (Hz)
-lower power = more hemostasis
-higher power = more cutting
✔✔where should be monitors in room be positioned? - ✔✔at eye level
✔✔where should you stand in relation to operative field as the surgeon? - ✔✔on
opposite side of anticipated operative field
✔✔how should your arms, elbows and wrists be positioned when operating? - ✔✔arms
<30 degree angle from trunk
elbows flexed 60-120 degrees
wrists protonated
GRADED A+
✔✔Troubleshooting: actual pressure in abdomen is higher than your set pressure flow
rate - ✔✔-check actual and set pressure of pneumoperitoneum and make sure it is
correct
-check status of relaxation of the patient (look for intraabdominal muscle contractions or
firmness of the abdomen which is different than anesthesia check for neuromuscular
twitch which has to do with the diaphragm relaxing not the abdomen)
-check to see if the valve connected to insufflator tubing is on/open
-check to make sure insufflator tubing is not kinked or someone standing on it
✔✔Troubleshooting: actual pressure in the abdomen is lower than your set pressure
flow rate and your flow states that you are on high flow - ✔✔-check insufflator tubing
and make sure tubing is connected to the insufflator and port
-check all ports and make sure the valves are closed
-check ports for leaking CO2 (e.g. skin/fascia incision to big and CO2 is leaking)
-check for distention of bowel and bladder catheter as CO2 can escape into other
hollow organs
✔✔Troubleshooting: actual pressure in the abdomen is lower than your set pressure
flow rate but your flow states that you have no flow - ✔✔-ensure power is on
-check gas tank level
-check CO2 gasket to ensure no leak or damage
✔✔what are the two options for delivering radiofrequency electricity? - ✔✔monopolar vs
bipolar
✔✔what type of circuit does monopolar use? - ✔✔electrosurgical unit (ESU) that
converts low frequency current from a wall source to high frequency current in order to
cut and coagulate; everything is delivered and received through electrodes
-i.e. high frequency goes through metal portion of laparoscopic instrument --> through
the tissue --> to the dispersive electrodes connected to the generator (i.e. grounding
pad)
✔✔how does tissue coagulation occur with monopolar? (describe process) - ✔✔-tissue
heating (temps > 60 Celsius) causes protein denaturation. As tissue cools, bonds
reform in a haphazard fashion leading to tissue coagulation.
-as tissue heating is occurring, water evaporates from tissue causing desiccation and
the tissue impedance (resistance) increases until current eventually stops flowing due to
the very high resistance.
-Clinically tissue will turn brown, bubble, and steam
✔✔definition of hemostasis - ✔✔fibrous binding of dehydrated/denatured of vessel
endothelium
,✔✔at what temp does internal water molecules vaporize and explode? - ✔✔100
degrees Celcius
✔✔how does current density relate to power and tissue resistance? - ✔✔-current
density is directly proportional to applied power
-current density is inversely proportional to tissue resistance
✔✔formula for tissue heating - ✔✔(current density)^2
= (current/area)^2
✔✔Formula for current density - ✔✔current (amps) / area (cm2)
-therefore if area is large (i.e large area of dispersive electrode like the grounding pad
on the patient), the less current density there is and thus the less the current heat and
vice versa
✔✔On what areas should the grounding pad not be placed on a patient and why? - ✔✔-
hairy skin, previous scars, metal implants
-increases risk if burn to patient
✔✔3 basic modes of operation on monopolar instruments (describe them) - ✔✔-Cut:
unmodulated waveform, low voltage; heats tissue quickly by causing cell water to steam
and then explode. Causes less thermal spread but poor coagulation. Electrode should
not contact tissue directly.
-Coag: intermittent waveform, high voltage; rapid surface heating causing a superficial
eschar formation and shallow depth of necrosis. (fulguration). Allows heat to be more
widely dispersed so cutting does not happen; can do noncontact mode and arc heat
from electrode to tissue
-Blend: mixes both wave forms allowing surgeon better control of desired tissue effect
✔✔Hazards of monopolar - ✔✔1. current diversion where current may through
unintentional pathways because it follows the path of least resistance
2. capacitive coupling: when the electrode (metal thing with current
like monopolar scissors) touches something it wasn't supposed to (e.g. suction irrigator
or another instrument etc), that passive instrument will serve as a capacitor and store
the charge and potentially unintentionally burn something else
3. excessive tissue heating can occur when trying to apply current to ligated tissue
(ligated tissue = small area = big current density = excess heat)
Ex: apply heat to ligated tissue (ex: appendiceal stump) can result in delayed
appendiceal blow out
✔✔what structures should you avoid when using monopolar? - ✔✔vascular structures,
ureter, nerves
, ✔✔How do you minimize risk of inadvertent tissue injury with monopolar? - ✔✔-inspect
insulation carefully
-use lowest possible power setting
-use lowest voltage waveform (pure cut or continuous low voltage waveform)
-use brief intermittent activation instead of prolonged activation
-don't activate unless in proximity of target tissue
-don't activate in proximity or direct contact with another instrument
-use bipolar if able
-don't use hybrid ports that mix metal and plastic
✔✔how does tissue coagulation occur with bipolar? (describe process) - ✔✔-tissue is
placed directly between 2 electrodes and current is only able to flow between these 2
(no need for grounding pad); current flows through much smaller amount tissue
-controlled delivery and high pressure from grasping tissue causing denaturation of
collagen within tissue wall
✔✔Difference between monopolar and bipolar - ✔✔-lower energy requirement and thus
less tissue necrosis compared to monopolar
-less lateral thermal spread given lower energy used
✔✔max diameter of vessel that bipolar can seal - ✔✔7mm
✔✔Hazards of bipolar - ✔✔-inadvertent damage to adjacent organs can occur
-if instrument has a cutting blade and you cut prior to adequate sealing, bleeding can
occur
-need to complete entire activation cycle before cutting
-will not work if metal is within the jaws (e.g. surgical staples)
✔✔what is ultrasonic energy? how does it work? - ✔✔-relies on mechanical energy and
tissue heating is generated by converting electric energy to high frequency ultrasonic
vibration (i.e. piezoelectric transducer) with minimal heat being transferred to passive
jaw
-50,000x/second (Hz)
-lower power = more hemostasis
-higher power = more cutting
✔✔where should be monitors in room be positioned? - ✔✔at eye level
✔✔where should you stand in relation to operative field as the surgeon? - ✔✔on
opposite side of anticipated operative field
✔✔how should your arms, elbows and wrists be positioned when operating? - ✔✔arms
<30 degree angle from trunk
elbows flexed 60-120 degrees
wrists protonated
