anesthetic management of robotic procedures in steep trendelenburg Flashcards
what are advantages of robotic surgery
- reduced blood loss
- reduced physiologic tremor or surgeon
- greater scale of hand movements
- greater hand eye coordination
- seven degrees of freedom of the instruments
- surgeon can sit with reduced fatigue
- 3D, HD stereotactic vision
- greater depth perception
what are advantages of robotic surgery
- reduced blood loss
- reduced physiologic tremor or surgeon
- greater scale of hand movements
- greater hand eye coordination
- seven degrees of freedom of the instruments
- surgeon can sit with reduced fatigue
- 3D, HD stereotactic vision
- greater depth perception
what are disadvantages of robotic procedures
- higher costs
- lengthy set up, patient positioning, and prep time
- inefficient with some surgeries compared to conventional laparoscopy
- bigger operating room required
- trocar placement not cosmetically favorable
- limited direct access to patient
- no feedback regarding tactile or force
- not easily converted to open in emergency
what is the triple threat?
altered physiology with 3 positions:
- lithotomy
- abdominal insufflation
- steep trendelenburg
what is steep trendelenburg?
> 30 degrees, max 45 degrees tilt head down
why is steep trendelenburg used in robotic procedures?
-maximal surgical exposure and optimal visualization
what position is prostate, colon, and GYN surgeries usually performed in?
max position (45 degrees)
- once robot is docked, table movement requires undocking (or trocar will rip where placed in pt.)
- surgeons avoid readjusting if more trendelenburg is needed
what are the effects of steep trendelenburg on the pulmonary system?
- abdominal contents shift cephalad
- diaphragm can shift cephalad as much as 8-10 cm
- trachea shortens; ETT may migrate to Rt. main branch
- reduced pulmonary compliance and FRC
- worsening ventilation-perfusion mismatch (shunt, perfusion w/o ventilation)
- PIPs increase as much as 50%
- chest binding and high insufflation pressures further reduce compliance (along with ST, up to 68%)
what insufflation pressures are recommended?
how does the pneumoperitoneum (abdomen insufflation) affect the pulmonary system
- increased intra abdominal pressure
- CO2 acting as a drug
- pulmonary management strategies must consider additional CO2
- elevated CO2 after deflation is explained by large amounts of CO2 stored in extravascular compartments of body slowly redistributing or exhaled
what has been shown to improve oxygenation after prolonged pneumonperitoneum?
PEEP of 5 cmH2O
how can the pt. in ST be ventilated?
- volume control or pressure control ventilation
- volume control leads to increased PiPs
- pressure control found to be more efficient resulting in lower PiPs and higher dynamic compliance
- lowering Vt and increasing RR are strategies used to maintain adequate ventilation
what caution needs to be taken with PCV?
- use volume control
- inadequate Vt if PC setting is too low
- excessive Vt can lead to volutrauma when pneumoperitoneum is released
what are intraocular effects of ST?
- debate whether autoregulation maintains OPP (MAP-IOP or CVP, whichever higher)
- increased ocular pressure has resulted in: retinal detachment, posterior ischemic optic neuropathy
- elderly have a higher baseline IOP
- hypotensive ischemic optic neuropathy: may be combination of periorbital edema and increased venous congestion leading to a compartment syndrome of optic nerve
- reduced ocular perfusion pressure r/t prolonged ST
- Hespan (colloid) used to help hold fluid in vascular compartment decreasing cerebral congestion
- very long cases may lead to vision loss
why is the CV system not the biggest concern with ST?
body often compensates for changes
