Lap BTL - bilateral tubal ligation

Diagnostic for pelvic pain, infertility, etc

LAVH - lap assisted vaginal hysterectomy

Ectopic pregnancy

lap choley

lap appy

hiatal hernia

diaphragmatic hernia

lap banding - weight loss

colon, spleen, liver

prostatectomy

HAL nephrectomy 

Hand assisted laparoscopic nephrectomy

What are the advantages of laparoscopic surgery? (5)

_____ surgical trauma

______ postop pain

improved postop _______ function

_______ hospital stays

earlier return to ______ activities

minimizes surgical trauma

less postop pain

improved postop pulmonary function

shorter hospital stays

earlier return to normal activities

*see chart slide 64

decreases in C-reactive protein

decreases in interleukin-6

(these reflect the extent of tissue damage)

decreased manipulation of the bowel

minimization of peritoneal incision

reduction in hyperglycemic response as compared to laparotomy

(nitrogen balance and immune fcn might be better preserved as a result)

Is the adrenocortical response decreased with lap surgery?

Excretion of ____ and _____ metabolites unchanged from laparotomy.

How can intraop stress be decreased?

No:

no benefit in reduction of adrenocotical response

(adrenocortical response more from visceral nociception than incisional stimulation)

excretion of cortisol and catecholamine metabolites unchanged from laparotomy

Intraop stress can be decr by giving alpha-2 agonists preop

yes

significant reduction in need for post-op analgesics

more visceral pain (spasm)

and

shoulder pain from diaphragmatic irritation

Pre-operative NSAIDs

intraperitoneal LA

more complete evacuation of pneumoperitoneum

laparoscopic cholecystectomy

gynecologic laparoscopy other than BTL

When is an intraperitoneal LA beneficial?

Conflicting results with _______.

particularly beneficial in gynecologic procedures

conflicting results with lap choley

What type of block is valuable in Lap BTL?

When is it more effective?

Mesosalpinx block

more effective if performed at start of procedure rather than end

(The mesosalpinx is the part of the broad ligament of the uterus enclosing a fallopian tube)

Give a valsalva breath at the end of case, which helps push some air out

close APL

give 15-20 cmH2O breath over 8-10 sec

less severe

&

resolves more quickly

elderly

obesity

COPD

smokers

PONV

2-dimensional image

difficulty in maneuvering instruments

40-75% incidence

(high)

Propofol anesthesia

Intraop antiemetics - often in combo

Supplemental analgesia to reduce opioid consumption

Emptying stomach intraop (OGT)

Nitrous oxide (Ron says incr PONV)

O2 supplementation in PACU

What positions are used for pelvic & lower GI surgery?

Which position predisposes pt to gas emoblism?

Trendelenburg position,

often accompained by Lithotomy

trendelenburg

Reverse Trendelenburg

decreased FRC

decreased lung volume

decreased lung compliance

elderly

obese

preexisting pulmonary compromise

What is the effect of laparoscopy on HR caused by?

What are the CV changes related to Trendelenburg?

What 2 mechanisms are activated?

Are these synergistic or antagonistic?

What heart rhythm predominates?

A fcn of peritoneal stretch as a result of incr IAP→decr HR 

Increased CVP & CO →Baroreceptor Reflex →Systemic Vasodilation and Bradycardia

The baroreceptor & atrial stretch reflexes compete against each other, bradycardia predominates.

Baroreceptor reflex--with incr CVP & CO, inhibit SNS & incr PNS to get back within norm BP

Atrial stretch receptors are also activated by incr R sided filling pressures (bainbridge reflex= incr SNS outflow to move blood out of atria, get incr in SNS & decr PNS, which would incr HR & contractility)

What is venous stasis exacerbated by?

What type of prophylaxis do we use?

reverse trendelenburg

pneumoperitoneum

lithotomy

pts need SCD

When are nerves more susceptible to injury?

What is the primary concern with Trendelenburg position and nerve injuries?

during stretch or ischemia

over-extension of the shoulder

common peroneal nerve

lateral femoral cutaneous nerve

femoral nerve

compartment syndrome

~30-50% compliance reduction (depends on IAP & preexisting disease)

FRC decreased secondary to elevated diaphragm

What is there a potential for with a  pneumoperitoneum? (respiratory)

We should avoid pressure of _____, particularly w/ _____.

If a pt becomes bradycardic as a result of insufflation, what can help?

potential for V/Q mismatch

avoid pressure of >14mmHg particularly with CV compromise

slow down rate of gas insertion or decr IAP a little

How does pneumoperitoneum affect PaCO2 in pts under controlled ventilation?

When does it plateau?

What happens if the PaCO2 keeps incr after this period of time? What could this indicate?

Change in PaCO2 depends on increased _____? 

PaCO2 progressively incr

Reaches plateau ~ 15-30 min after beginning of CO2 insufflation

Any sig. incr PaCO2 after this period requires a search for a cause such as subQ emphysema, gas embolism, MH

incr in PaCO2 depends on IAP

Mimics PaCO2 (but ~4-5 mmHg lower):

progressively incr & reaches plateau ~ 15-30 min after beginning of CO2 insufflation in pts under controlled ventilation

How does local anesthesia affect PaCO2?

What is this d/t?

PaCO2 unchanged due to:

compensatory increase in minute ventilation

GETA with spontaneous ventilation

________ PaCO2 despite ____ minute ventilation, due to _____ compliance and ventilatory _______ from anesthetics

Don't they compensate?

How can CRNA fix this?

Increased PaCO2 despite increased minute ventilation, due to decreased compliance and ventilatory depression from anesthetics

pt tries to compensate, but can't compensate for laparoscopy, pneumoperitoneum & GA all at same time

since they are intubated, we can incr MV to blow off CO2

What are the 2 causes of increased PaCO2 during pneumoperitoneum? Which is the number 1 cause?

How do we know that absorption of CO2 is the main reason for the increase in PaCO2 seen with pneumoperitoneum?

absorption of CO2

(#1 cause)

mechanical causes

b/c if do laproscopy with Helium etc there is minimal to no increase in PaO2

(no increase with healthy pts per Ron)

Impaired ventilation and perfusion:

 abdominal distention

 positioning

 inadequate ventilation

-Iatrogenic

-Ventilatory depression with spontaneous respiration

Pts can get increased PaCO2 d/t ventilatory changes and mechanical forces on top of absorption mechanism IF have...(2)

What happens as IAP continues to increase?

Where do we like to keep the IAP?

 cardio-respiratory compromise

or IAP >10mmHg

The vent/mechanical effects play a greater role as IAP increases further

 keep IAP ≤14mmHg

(not my job to monitor)

subcutaneous emphysema

pneumothorax (pneumomediastinum, pneumopericardium)

endobronchial intubation

gas embolism

see chart on slide 32

an increase in ETCO2 following the inital plateau

(also consider MH with increase in EtCO2)

swelling & crepitus

accidental extraperitoneal insufflation

necessary extraperitoneal insufflation

inguinal hernia

pelvic lymphadenectomy

hiatal hernia repair

hyperventilation and suspend insufflation/surgery briefly until CO2 blown off

continue mechanical ventilation at conclusion of case until ETCO2 returns to normal

What is a capnothorax?

What causes it?

increased airway pressure

increased EtCO2

(CO2 in chest cavity = inc surface area for absorption)

auscultation & CXR

reduced air entry

hyperresonance

What is a pneumothorax?

What causes it?

increased airway pressure

decreased EtCO2

auscultation & CXR

 decr air entry

 hyperresonance

How do we manage a CO2 pneumothorax (capnothorax)? (4)

When and how will it resolve?

stop N2O if using (just don't use it b/c of increased N/V issues & increase in size of air emboli if occur - per Ron)

adjust vent to correct hypoxemia

PEEP

reduce IAP

resolves spontaneously - very highly diffusable

thoracentesis

no PEEP

(would just push more air into the thorax)

What is the main difference in diagnosing capnothorax vs pneumothorax?

What is a difference in managing these?

Capnothorax: increased ETCO2 (CO2 in chest cavity) 

Pneumothorax: decreased ETCO2

capnothorax: use PEEP

pneumothorax: no PEEP

How do you diagnose an endobronchial intubation?

How do you manage this?

decreased SpO2

increased airway pressure

auscultation (reduced air entry)

pull tube back some

When does a gas embolism typically present?

What is it d/t?

typically presents at the start of insufflation

d/t placement of insufflating needle into a blood vessel or organ

Is CO2 soluble in blood?

CO2 has a ____ carrying capacity and is ___ eliminated

yes, very soluble in blood

high carrying capacity

rapidly eliminated

So absorption issues can resolve quickly etc

What may a large volume of CO2 in the RA or vena cava result in?

In which pts in particular does this happen?

R→L shunt producing gas embolization of the coronary and cerebral vasculature

 particularly with patent foramen ovale

How do we diagnose a gas embolism? (4)

What is the definitive diagnosis of a gas embolism?

decr EtCO2

decr SpO2

tachycardia

hypotension

millwheel murmur

aspiration of gas or foamy blood from a central venous line

*List the steps for managment of a gas embolism. (8 total)

Step 8 - consider ______ treatment if gas in cerebral circulation

1. stop insufflation

2. release pneumoperitoneum

3. steep trendelenburg

4. left lateral decubitis

5. stop nitrous oxide

6. 100% oxygen

7. central venous line to aspirate gas

8. consider hyperbaric oxygen treatment if gas in cerebral circulation

controversy exists over whether the increased IAP during laparoscopy predisposes the patient to increased aspiration risk

may be compensated in some part by increased tone of lower esophageal sphincter

(d/t SNS stimulation with insufflation)

minimal to no change in HR

decreased CO -initial 10-30% decrease with insufllation

increased SVR -d/t incr. catecholamines/vasopressin

increased BP -d/t incr SVR

*see chart on slide 41

How much is the CO decreased initially during insufflation?

proportional to?

independent of?

decreased 10-30% initially

proportional to increase in IAP

independent of patient positioning

d/t incr IAP:

increased SVR (SNS)

decreased venous return (compression)

What level of IAP causes decreased venous return  to be seen with pneumoperitoneum? How does this occur?

What attenuates the decrease in CO see? (2)

at IAP>10mmHg

increased IAP→caval compression→ ↑venous resistance & pooling of blood in legs

attenuated by:

fluid preload

wrapping legs or SCDs

What is the change in SVR with insufflation?

What is this NOT a result of?

increased SVR

NOT a result of decreased CO

(but rather d/t incr. SNS)

attentuated by trendelenburg

accentuated by reverse trendelenburg

How does vol loading affect CI & SVR w/ pneumoperitoneum?

Should we always vol load?

vol loaded pts better able to maintain CI

SVR lower (closer to baseline)

yes, vol loading is always important unless there is compelling reason not to

*see graph slide 37

What causes/mediates increased SVR seen with pneumoperitoneum?

What cause the release of these mediators? (2)

mechanically and neurohumorally mediated:

increased vasopressin, catecholamines

increased intrathoracic pressure
stimulation of peritoneal receptors

What is the potential for thromobembolic complications due to?

How do we try to prevent this?

Is this worse with laparoscopy?

potential d/t lower limb venous stasis

most patients are wearing SCDs

no measurable increase seen with laparoscopy in & of itself but positioning plays a big role per Ron

What are the renal changes seen with pneumoperitoneum?

How is this fixed?

~50% reduction in UOP, GFR, & renal blood flow

promptly restored when pneumoperitoneum released

How is splanchnic and hepatic blood flow affected?

Why?

appear not to be clinically significant

b/c CO2 vasodilates splanchnic vessels = compensates for compression per Ron

How is cerebral blood flow affected?

What should we do for pts at risk for complications with increased CBF and ICP?

increased d/t elevated PaCO2 (vasodilates)

maintain normocarbia in pts at risk

How is IOP affected in pts with healthy eyes?

What if they have glaucoma?

no change in absence of pre-existing disease

slight increase seen in glaucoma animal model SO DONT USE LAPROSCOPY with GLACOMA PTS

low CO 

decr CVP

high SVR

high MAP

*all these issues will become worse with insufflation

How do you manage patients with heart disease going for a laparoscopic surgery?

Which pts tend to need higher insufflation pressures?

preop fluid load

slow insufflation with minimum IAP necessary

if needed, a selective arteriorlar dilator

ie Hydrazaline

Obese

What is the most common arrhythmia w/ pneumoperitoneum?

What is it due to?

bradycardia

d/t reflex increase of vagal tone from stretch of the peritoneum

can also see with traction of fallopian tubes and round ligaments

Bradycardia is more severe with pts on ______?

What can it progress to?

may be more severe in B-blocked patients

may progress to asystole

1. stop insufflation

2. release pneumoperitoneum if necessary (↓stretch)

3. atropine

4. ACLS as needed

5. less likely to recur with a deeper plane of anesthesia, if tolerated

insufflation

underlying cardiac disease/rhythm disturbance

gas embolism

adnexal surgery (ovarian cyst)

appendectomy

cholecystectomy

simulation of premature labor

damage to gravid uterus

teratogenicity of anesthetic gases

Involve the Obstetrician:

timing of procedure

tocolysis

monitoring

What are other considerations for lap surgery in the pregnant patient?

minilap for trocar access

fluid load as in others

maintain normal maternal EtCO2

left uterine displacement

increased ICP

hypovolemia

VP or PJ shunt

VP=venticularperitoneal

PJ=peritoneojugular

(Miller 2195 states that lap can be performed safely in pts w/ VP or PJ shunt w/ unidirectional valve resistant to IAPs used during pneumoperitoneum)

heart disease 

renal insufficiency 

DVT prophylaxis 

preop NSAIDs (reduce postop pain & opioid requirements) 

anesthetic adjuncts:

dexmedetomidine

clonidine

(these both decr intraop stress response & improve HD stability)

In positioning the patient for a laparoscopy, what should you be mindful of?

How much do you tilt pt?

careful padding and placement of braces

use only amount of tilt needed (~15-20 degrees) & adjust tilt slowly to avoid sudden HD & resp changes

When should you verify ETT placement when doing anesthesia for a lap surgery?

Consider ____ placement of OGT to decompress stomach

*____ _____ prior to pelvic trocar placement

verify ETT placement following position changes & insufflation

consider early placement of OGT to decompress stomach

empty bladder prior to pelvic trocar placement

EKG

BP

pulse ox

capnography

auscultation - esophageal or precordial

What are the invasive monitors that can be used?

Are they routinely used?

 TEE likely more effective than CVP or PA due to increased intrathoracic pressure from pneumoperitoneum (this interferes w/ measurements)

no, rarely used

What is the safest anesthesia technique?

Why?

general anesthesia with ETT

allows superior control of ventilation

N2O - dont use at all with laps per Ron b/c of risk for N/V and increased size of any air emboli

propofol infusion

MR

antiemetics

avoid in intestinal surgery

controversy over NV

Why is propofol beneficial?

When should it be avoided?

decreased NV

avoid with embryo transfer

Is a LMA a good option?

Why?

not really

less protection of airway

less control of ventilation

incr airway pressure d/t pneumoperitoneum & decr thoracopulmonary compliance

1/3 of deaths related to laparoscopic procedures were related to anesthetic complications during GA without intubation 

SO PUT AN ETT IN

Is a local & epidural ok for a lap procedure?

requires?

need to?

best with?

What does Ron think?

has been performed successfully

requires a skilled surgeon and willing patient

need to minimize IAP

maybe best with gasless lap

(according to Ron, this is not a good option)

What may the sympathetic block with an epidural during larparoscopy leave _____ unopposed.

When may an epidural be helpful?

vagal reflexes = more brady risk

associated vasodilation may be helpful in select cardiac patients

In the post-op care of lap patients, what 3 things may persist for a short while?

What else is common postop and can be prolonged for awhile?

increased SVR 

increased O2 demand

increased RR and EtCO2

 (above not usually a problem)

 NV

What is the main cause of complications with laparoscopic gynecologic surgery?

When do most complications occur for this type of Sx and why?

intestinal injury

vascular

burns

most occur at the beginning w/ creation of pneumoperitoneum & involve trocar

The main complications for general laparoscopic surgery (ie cholecystectomy) are?

When do the complications usually occur?

bowel perforation

CBD injury (common bile duct)

hemorrhage

occur later closely r/t surgical procedure, many involve hemorrhage

What inert gases can be used as alternatives to CO2 pneumoperitoneum?

When using inert gases, are respiratory and HD effects decreased? Why?

 helium and argon

 No, respiratory and HD effects of pneumoperitoneum persist

bc IAP is increased

PaCO2 not elevated

smaller increase in BP

greater decrease in CO

low blood solubility (safety issues r/t gas embolism)

 advantages of using a gasless lap

r/t: resp and HD?

r/t: renal and splanchnic?

avoids respiratory and HD issues of pneumoperitoneum

no decrease in renal and splanchnic perfusion

What are the advantages of using a gasless lap

r/t: port-site metastases?

r/t: pain & NV with a choley?

reduced incidence of port-site metastases w/ lap Sx for cancer

decreased pain & NV with choley

ROBOTICS

What is scaling?

ROBOTICS

What is registration?

autonomous action based on registration

(programmed off-line & tasks are invoked on command; precise tasks such as drilling & probe insertion are based on registration; ex: robots used in ortho & neurosurg)

What does an assist device do?

Is it autonomous?

controls instrument location and guidance

not autonomous, requires surgeon input

What is a telemanipulator under control of?

How does it work?

under constant user control

mimics the operator's hand motions in exact or scaled motion

 (the system allows surgeon to be physically remote from pt, but surgeon can also be in OR)

What are the advantages of robotic surgery? (6)

increased ______

filter of _____

less _____

______ hospital stay

better _____ result

potential for ____ ______ surgery

increased precision

filter of tremor

less pain

shorter hospital stay

better cosmetic result

potential for long distance surgery

laparoscopy

thoracoscopy

mitral valve repair

general surgery

laparoscopy

1987 - 1st lap choley done completely with telemanipulation

1988 - 1st totally endoscopic CABG

What will some procedures with robotics require?

What's important to remember about the robots arms being engaged?

some procedures will require steep tilt of the patient

once the robot arms are engaged, the position can't be changed without removing them

With thoracic procedures and robotics, what may be required for ventilation?

What is a standard monitor?

may require prolonged one lung ventilation

TEE pretty standard monitor

choley

pyloroplasty

adrenalectomy

anti-reflux surgery

internal mammary harvesting

CABG

mitral valve repair

ASD closure

ligation of PDA

TURP

radical prostatectomy

vas deferens reanastomosis

gynecology - fallopian tube reanastomosis

orthopedics - total hip and knee

laser microsurgery

RAMS = robot assisted microsurgery system 

jointly developed with NASA

100:1 scaling

superior tremor filtering