MIS Principles
What gas is used for insufflation of the abdomen
CO2
To what pressure is the abdomen insufflated during robotic/laparoscopic surgery?
10-15 mmHg
Name two absolute contraindications to laparoscopic/robotic surgery
1. Hemodynamic instability
2. Surgeon discomfort or inexperience with robotic/laparoscopic surgery
Name two requirements for dispersive pad (Bovie pad) placement
1. Placed over large muscles
2. Not placed over bony prominences
3. Not overlying metallic implants
4. Not overlying cardiac implants
Is low or high frequency ultrasound better for visualization of superficial structures?
Higher frequency
What is the incidence of bowel or vascular injury with Veress needle or trocar insertion?
0.1%
Describe the effects of pneumoperitoneum on the renal system
Decreased renal blood flow can result in oliguria which should resolve postoperatively
Name at least two relative contraindications to robotic/laparoscopic surgery
2. Severe cardiopulmonary disease
3. Cirrhosis with portal hypertension
4. Inability to tolerate general anesthesia
5. Large abdominal/pelvic mass
What is the difference between monopolar and bipolar energy?
Monopolar: Energy is transferred through the patient from the instrument to the dispersive pad
Bipolar: Energy is transferred through tissue between tips of the instrument.
Does Dacron (polypropylene) or Gore-Tex (PTFE) allow for fibroblast ingrowth?
Dacron does allow fibroblast ingrowth, PTFE does not
Rank the following prep solutions in terms of flammability risk: Hibiclens, Betadine, Chloraprep
Betadine < Hibiclens < Chloraprep
Describe the effects of pneumoperitoneum on the cardiac system
Decreased preload and increased afterload
Overall decrease in cardiac output
Possible rhythm changes such as bradycardia secondary to a vagal response
Name at least two ways to prevent robotic arms from clashing during case
1. Spacing out incision sites
2. Burping the instrument arms after docking
3. Targeting the camera at start of case
What is the mechanism of a laser in coagulation?
Returns electrons to ground state and releases energy as heat
What does FRED stand for? (Laparoscopic camera lens cleaning solution)
Fog Reduction Elimination Device (antifoam solutions to clean laparoscopic camera lens)
What is Palmer's point and where is it located?
Common location for Veress needle insertion
Left midclavicular line 3cm below the costal margin
Describe the affects of pneumoperitoneum on pulmonary function
Decreased functional residual capacity
Increased peak airway pressures
Reduced pulmonary compliance secondary to increased abdominal pressure pushing the diaphragm cephalad
Name two ways to confirm intra-abdominal Veress needle placement
1. Hanging drop test: saline flows freely through Veress needle into abdomen
2. Tactile loss of resistance with insertion
3. Low insufflation pressures (≤ 8 mm Hg) with low-medium flow
How does Argon beam work?
Argon is an inert noncombustible gas which is energized allowing for superficial coagulation
It is non contact and creates a flexible eschar with decreased risk of rebleeding.
What percentage of aromatized particles can pass through a surgical mass during electrocautery?
70%. Suctioning of electrocautery smoke is important to decrease exposure to carcinogens
Describe the treatment of CO2 embolus
Put patient in trendelenburg position, left side up
Attempt aspiration of CO2 via central line
Describe the signs of a CO2 embolus
Sudden transient rise in ETCO2 followed by a drop in ETCO2
Followed by hypotension
When do bowel injuries usually present following an unrecognized thermal injury in the OR?
5-7 days
How does the Harmonic scalpel work?
Disrupts protein to hydrogen bonds, resulting in coagulation
Describe the phenomena of antennae coupling with regards to electrosurgical energy injury?
When the energy from the monopolar device or its cable transfers to nonelectrified wires such as neuromonitoring and ECG leads. This can result in burns at the sites where these wires are attached to the skin.