1
Q
What are the common laparoscopic surgeries?
A
- GI
- gastric
- colonic
- splenic
- hepatic
- gallbladder
- gynecologic
- hysterectomy
- Urologic
- nephrectomy
2
Q
How does laparoscopic surgery compare with general surgery?
A
- lower pain scores and opioid requirements
- earlier ambulation and return to normal activities
- lower incidence of post-operative ileius
- usually faster recovery, shorter hospital stay (SDS)
- reduced post-op pulmonary/diaphragmatic dysfunction
- not for everyone, can still have severe post op pulmonary dysfunction leading to hypoxia
- less stress response and wound complications
- usually lower cost
3
Q
What are the relative contraindications of laparoscopic surgery?
A
- Increased ICP
- hypovolemia
- V/P shunt or peritoneojugular shunt
- ok if they have unidirectional valve resistant to IAP (intra-abdominal pressure)
- Severe CV disease
- severe respiratory disease
4
Q
How is the laparoscopic technique done?
A
- small incisions made and intraperitoneal space is insufflated with CO2
- Trochars may be inserted blindly or by using a mini laparotomy (this is safer)
- After placement is verified , abdomen is insufflated until intraabdominal pressure reaches goal (usually 15 mmHg or less)
5
Q
How can the pneumoperitoneum be insufflated?
A
- CO2
- stimulates cardiovascular system
- Inert gasses (helium and argon)
- prevent the increase in absorbed CO2
- accentuates decrease in cardiac output
- Gasless laparoscopy
- more difficult for surgeon
- relies on wall lift obtained by a fan retractor
- may be safer for cancer patients in reducing metasis
- less hemodynamically challenging for really fragile patients
- increases surgical time and cost
6
Q
Why is CO2 the gas of choice?
A
- more soluble in blood than air, helium, oxygen, or nitrous oxide
- capacity for carriage in the blood
- rapid elimination
- better outcomes compared with He embolus)
- nonflammable/noncombustible can be used with diathermy
7
Q
What changes can CO2 in the peritoneum cause?
A
- PaCO2 progressively rises to reach a plateau 15-30 minutes after insufflation
- If it continues to rise, search for a pathologic cause (embolism, emphysema, MH)
- respiratory and cardiovascular changes
8
Q
What should you consider regarding the anesthesia for a laparoscopic procedure?
A
- It can potentially be a high-risk procedure
- pneumoperitoneum + positions required = pathophysiological changes
- often long duration
- risk of unsuspected visceral injury
- difficulty in evaluating the amount of blood loss
- at risk for aspiration of gastric contents
9
Q
Why does the PaCO2 increase during laparoscopic surgery?
(9)
A
- absorption of CO2 from the peritoneal cavity (primary reason)
- abdominal distension
- VQ mismatch
- decreased FRC
- decreased pulmonary compliance
- Patient position
- VQ mismatch
- Depression of ventilation by anesthetic agents if spontaneous breathing
- CO2 emphysema- SQ or body cavities
- Capnothorax (pneumothroax with CO2)
- CO2 embolism
- Selective bronchial intubation
10
Q
What affects the absorption of CO2?
(4)
A
- Diffusibility of gas
- absorption area
- vascularity of insufflation site
- greater in pelvic surgery than in intraperitoneal surgery
11
Q
How much does insufflation decrease pulmonary compliance?
How much should you increase alveolar ventilation?
A
- pulmonary compliance decreases 30-50%
- increase alveolar ventilation 10-25%
12
Q
What are the hemodynamic changes seen in laproscopic surgeries?
(9)
A
- Decreased CO 10-30% (depends on insufflation and position)
- decreased venous return
- decreased LVEDV
- Increased intrathoracic pressure
- increased right atrial and PA occlusion pressures
- minimal increase HR
- Increased aBP, PVR, SVR
- catecholamines
- renin-angio
- vasopressin
- arterial compression by high IAP
- may increase myocardial wall tension and O2 demand
- increased risk for arrhythmias
- d/t peritoneal stretching, intolerance of hemodynamic changes, and increased CO2
13
Q
Explain the flow chart of what occurs with increased intra-abdominal pressure
A
14
Q
What are things a CRNA can do to attenuate the changes caused by increased abdominal pressure?
A
- fluid load before insufflation
- us alpha-2 agonists like clonidine, dexmedetomidine, and beta blockers
- Remifentanyl can help reduce hemodynamic response
- In pts at risk for CHF:
- remember that normalization of HD parameter does not occur for at least one hour post-op so CHF can develop in PACU
15
Q
Describe hemodynamic alterations in:
Splanchnic
kidney
head
A
- Splanchnic
- usually unchanged- mechanical compression + neuroendocrine vasoconstriction balance by hypercarbic dilation
- Kidney- decreased GFR, renal plasma flow, UOP
- Head-
- increased cerebral blood flow and ICP in steep t-burg
- increased IOP in steep t-burg
16
Q
What should you consider during induction for a laparoscopic surgery?
A
- GA w/cuffed ETT and controlled ventilation
- increased MV (20-30%) and PIP often required
- adjust RR, Vt (6-8 ml/kg), PEEP (5-10) and PIP
- Goals: ETCO2 = 35 mmHG, PIP low 30’s
- aspiration risk
- RA has been used- risky
- need high block (T4-5) which causes SNS denervation, making it more difficult to compensate
- shoulder and distension pain incompletely alleviated
- Intra-abdominal pressure limit of <15 mmHg is best to avoid CV compromise
- ASA III-IV and/or abnormal gradient PaCO2:ETCO2 require invasive monitors
- blood gas and BP
17
Q
Can you use an LMA for laparoscopic surgeries?
A
- ETT
- secures airway (aspiration protection)
- allows for control of ventilation
- ProSeal LMA (controversial)
- spontaneous ventilation
- lower incidence of sore throat
- lower pain scores, less analgesic medications required, less PONV
- 1/3 of deaths during lap surery occurred during GA without ETT
- unable to:
- secure the airway
- control ventilation
- administer muscle relaxation
18
Q
What should you consider regarding positioning for laparoscopic surgery?
A
- prevent nerve injury
- lithotomy: common peroneal
- shoulder braces: brachial plexus
- Tilt should not exceed 15-20 degrees
- make changes slowly
- recheck the ETT position after every change
- consider less aggressive fluid replacement in head down position d/t edema
19
Q
What should you consider regarding GA maintenance for a laparoscopic surgery?
A
- Standard maintenance
- balanced techniqe appropriate or TIVA
- Consider TIVA if pt has history of PONV
- Continue muscle relaxation
- new evidence suggests this might not be necessary
- Continue careful monitoring of pulmonary and hemodynamic status
- Watch for endobronchial intubation during position changes
20
Q
What do you do if the laparoscopic procedure is converted on an open procedure?
A
- Supine position
- new fluid plan- 3rd space losses will increase
- new pain management plan- opioid requirements will change
- New ventilator settings- may need to reduce rate and increase Vt
21
Q
What kind of intraoperative surgical complications should you monitor for?
A
- Vascular injury- trocar insertion/veress needle
- aorta, ICV, iliac vessels, cystic hepatic arteries, retroperitoneal hematoma
- GI- trocar insertion/veress needle
- bowel, liver, spleen, mesenteric
- Cardiac
- dysrhythmias- hypercarbia, vagal, BP changes
- SQ emphysema- extra-peritoneal insufflation
- accidental or inguinal hernia repair
- Capnothorax, capnomediastinum, capnopericardium
- diaphragm defect, pleural tear, bullae rupture
- CO2 embolism
- direct needle placement in vessel
- gas insufflation into abdominal organ
22
Q
What makes a procedure higher risk for SQ emphysema or capnothorax?
A
- procedure > 200 minutes
- more than 6 ports used
23
Q
What is the pathophysiology of Gas Embolism?
A
- Depends on size of bubbles and rate of entrainment
- Can cause vapor lock in vena cava and RA
- Obstruction to venous return
- Acute RV hypertension = paradoxical embolism (to cerebral and coronary vasculature)
- Circulatory collapse
24
Q
How is Gas embolism diagnosed?
Ideally?
Real world?
A
- In the ideal world:
- Trans-esophageal echo (TEE)
- Swan-Ganz catheter
- precordial dopplers
- In the real world:
- Pulse oximetry (hypoxemia)
- Esophageal stethescope- millwheel sound
- ETCO2 decrease
- Aspiration of gas from CVP
- hypotension
25
How is Gas embolism treated?
* Stop insufflation and desufflate
* Position
* steep trendelenberg
* left lateral decub- to displace from RV outflow tract
* d/c N2O and give 100% FiO2
* hyperventilate
* place CVP
* CPR
* consider CPB
26
What should you consider for GA emergence and post-operatively for laparoscopic cases?
* Procedures are associated with intra-abdominal, incisional, and shoulder pain
* irritation of diaphragm and/or visceral pain from biliary spasm
* treat with:
* opioids
* NSAIDS
* acetaminophen
* LA (Tap block)
* PONV
27
What affects PONV of laparoscopic surgeries?
* experienced by 40-75% of patients after laparoscopic procedures
* meds that can help:
* propofol
* versed
* decadron
* zofran
* minimize opioids
* gastric decompression
Advanced Principles- Fall 2018
flashcards
Decks in class (17)
# Cards
-
Difficult Airway- Lots of Review27
-
Difficult Airway22
-
Neuraxial Anesthesia17
-
Neuraxial Anesthesia- physiologic changes and Techniques41
-
Regional- upper body32
-
Regional- lower body13
-
Regional- Technique24
-
Ambulatory25
-
Laproscopic27
-
Burns27
-
Burns- management and anesthetic considerations20
-
Trauma62
-
Remote locations39
-
Remote locations 228
-
Orthopedics27
-
Orthopedics- Lower39
-
Ortho- Spine18
