Case 38 - laproscopic robotic prostatectomy Flashcards
what are your primary anestheic concerns for robotic assisted laproscopic radiacl prostatectomy (RALP)?
- physiologic effects of pneumoperitoneum in t-berg
- restricted access to pt due to robot
- prevention or tx of complications 2/2 t-berg, exaggerated lithotomy, pneumoperitoneum
What are the cerebrovascular effects of pneuoperitoneum in steep t-berg position?
- decrease cerbal vascular drainage –> increase CBV and increase CSF
- increase ICP
- pneumoperitoneum –> increase intrabdominal pressure –> transmits to thorax and superior vena cava –> hinders cerebral venous drainage –> increases CBV –> increase ICP
- pneumoper -> inc PaCo2 -> cerebral vasodilate
- t-berg also increases ICP due to poor cerbreal venous drainage
- CPP does not appear to be compromised.
Describe the respiratory effects of pneumperitoinum in steep t-berg position?
- Increase peak airway and plateau pressures
- decrease FRC
- decrease pulmonary compliance
- pneumoperitoneum increase intrabdominal pressure –> decrease pulm compliance and tidal volumes –> increase peak airway and plateau pressure
- along with steep t-berg –> decrease FRC, decrease pulm compliance, redispose to atelectasis
- due to t-berg, pulmonary blood increases in lungs, at risk for interstital edema 2/2 increase hydrostatic pressure (lung below level of heart)
what would you do to maintain minute ventilation in a patient with pneumoperitoneum in t-berg position?
- will need to increase peak airway pressure to overcome airway resistance and allow gas flow into lungs.
- avoid extreme high PAP due to risk of barotrauma
- permissive hypercapnia
- increase RR to maintain constant minute ventilation (since tidal volume will decrease due to position)
- consider I:E ratio change
What are the hemodynamic effects of pneumoperitoneum in steep t-berg position?
- decrease or unchange HR, CO, MAP
- increase CVP and SVR
- increase stroke volume/preload
- pneumoperitoneum can cause aortic compression –> increase afterload/SVR
- CVP increase with steep t-berg due to dependent flow of blood (gravity)
- be mindful that insufflation can cause vagal reflex (bradycardia)
What are complications of pneumoperitoneum and steep t-berg posistion during RALP?
- CO2 sub-q emphysema
- crepitus
- hypercapnia
- pneumothorax / mediastinum / pericardium
- venous gas embolism
- sudden cardiovascular collapse
- lose CO2 tracing
- positioning
- slide off table
- brachial plexus injuries/peripheral nerve injury
- facial/laryngea/pharyngeal edema
- difficult extubation
- re-intubating difficult
- ocular injuries
- ION
- abrasion
what are the complications of CO2 subcutaneous emphysema?
CO2 sub-q emphysema
- crepitus (can compress airway)
- hypercarbia (increase RR)
- pneumothorax / mediastinum / pericardium
- crepitus can be felt. swelling of neck can interefere with breathing, hypercapnia causes elevated RR
- if pt has severe crepitus —> mech ventilate until resolved
The patient during RALP has acute hypotension, you suspect venous gas emboli, what do you do?
venous gas embolism
- CO2 used for insufflatoin, more solubule then air therefore it is less threatening to cause air lock then similar sized emboli composed of air
- Co2 gas embolism can occur with intial insufflation and dissection of deep dorsal venous cmplex
MGMT
- notify sx to stop immedietly, desufflate abdomen, undock and remove robot for pt access
- maintain steep t berg and tilt patient left side down (shifts emboli away from RVOT)
- d/c N2O, hyperventilate with 100% to facilitate removal of CO2
- can attempt to aspirate gas with CVC
- ACLS if necessary
At the end of the case, you extubate the patient and he experiences SOB and stridor, you suspect laryngeal edema. How could you have prevented this?
Facial/pharyngeal/larygeal edema
- occurs with combo of steep t berg and pneumoperitoneum
- increase IV fluids, reduced venous outflow due to pneumopertioneum, and steep berg causing pooling of head/neck contribute to this
Prevent
- restrict fluids, minimize time in steep t berg
- assess for facial and conjunctival edema (surrogate for airway edema)
- cuff leak test
- when in doubt, keep patient intubated + mech vent, sitting position, diuretics, and delay extubation until edema resolves
- consider extubation over airway exchange catheter
- if extubated patient experiences SOB and stridor, suspect airway edema and emergently reintubate.
what are some causes of ischemic optic neuropathy in RALP patients?
ION
- typically occurs in spine cases 2/2 prone position, hypotension, acute blood loss
- can occur in cases of severe t-berg as well
ION in RALP
- decrease venous ocular outflow - steep t berg and pneumperito –> increase venous pressure in head/neck due to pooling of blood
- decrease arterial flow –> due to increase backflow of venous pressure which can increase IOP
- increase PaCo2 can cause vasodilation and increase IOP
what are preanesthetic concerns for patients presenting for RALP?
patients are typically > 60 and have comorbid conditions
- preexisting neurological deficits
- at risk for brachial plexus/peripheral nerve injury
- document deficits, have awake patient in lithotomy patient to see if they r comfortable
- CAD
- cardiac reserve, stress test?, echo?, PCI/DES/BMS?
- COPD
- patients may have lung bullae/blebs
- sx associated with high PAP –> barotrauma
- obesity
- can slide off table
- high incidence of CAD, pulm dysfunciton, DM (neuro deficits)
anesthetic technique for RALP?
- General anes with ETT
- controlled ventilation required
- main stem with pneumoper and t berg (abdominal contents shift diaphragm upwards)
- invasive lines +/-
- dependent on comorbid conditions
- place before robot is docked (limited access)
- muscle relaxation
- required to faciliate pneumoperitoneum/surgical exposure
what is your fluid managment going to be for RALP sx?
avoid excessive fluid administration
- at risk for facial/laryngeall/pharyngeal edema
- may also obscure surgical view during vesicourethral anastomosis