Dr Santanu Kumar Dash

to understand the principles of anaesthesia for laparoscopic surgery

to increase awareness of the risks of CO2 peritonium

benefits of laparoscopic surgery from patient’s point of view

special considerations in geriatrics, COPD, heart disease, pregnancy, paediatrics and obese patients

Laparoscopy introduced in 20 th Century

1975 : first laparoscopic salpingectomy

1970 -- 80 : used for gyne procedures

1981: Semm, from Germany,1st lap appendectomy

1989: laparoscopic cholecystectomy

Day care surgery Shorter hospital stay Improved cosmesis Less post-op ileus Faster recovery Rapid return to normal activities Minimal pain Small scar Better preservation of resp fn

More expensive More operating time Difficult in complicated cases Potential for major complications

in inexperianced hand

General Surgery: ▪ Cholecystectomy ▪ Appendicectomy ▪ Varicocoelectomy ▪ Hernioplasty ▪ Diagnostic laparoscopy ▪ Hiatus hernia repair

▪ Adhesiolysis

OBG: ▪ Diagnostic tool for infertility▪ Ectopic pregnancy ▪ Myomectomy ▪ LAVH ▪ Endometriosis

Thoracic Surgery: ▪ Sympathectomy

Mediastinoscopy

Diaphragmatic hernia Acute or recent MI Severe obstructive lung disease Increased ICP V – P shunt Hypovolemia CCF Valvular heart diseases

CO2 pneumo peritoneum

Due to patient positioningCardiovascular effects Respiratory effects Gastro intestinal effects Unsuspected visceral injuries Difficulty in estimating blood loss Darkness in the OR

Insufflator Gas used N2O /CO2 /Argon /He/ Air

Preferred gas : CO2 Working pressure : 12 to 14 mm Hg Slow inflation of 1 liter / minute(Air & O2 –risk of embolism high. N2O –bowel distension,risk of

explosion,PONV. He & Argon not available here- embolism)

CO2 as Insufflator Gas

▪ More soluble in blood than air ▪ Carriage is high due to bicarbonate

buffering and combination with Hb ▪ Rapidly eliminated by lungs ▪ Inert & not irritant to tissues

Cardiovascular effects depends on

▪ Patient’s preexisting cardiopulmonary status

▪ the anesthetic technique ▪ intra-abdominal pressure (IAP) ▪ carbon dioxide (CO2) absorption ▪ patient position ▪ duration of the surgical procedure

- There is biphasic response on CO - If IAP <10mmHg, milking effect on veins CO - If IAP >15mmHg, 10%-30% reduction in CO

increase in systemic vascular resistance, mean arterial pressure, and cardiac filling pressures

more severe in patients with preexisting cardiac disease

significant changes occur at pressures greater than 12 - 15 mmHg

Increased noradrenalin levels leads to

increased SVR increased plasma renin activity (PRA)

due to increased intra-abdominal pressure (IAP) and the local compression of renal vessels

Hypertension, tachycardia leading to increased myocardial oxygen demand

Hypercarbia and acidosis

common during insufflation and during desufflation

Volatile anaesthetic agents Hypercarbia, hypoxia and gas

embolism ppt tachyarrythmias and VPDs

Sudden stretching of peritoneum causes vagal stimulation

Light planes of anaesthesia

Management : Adequate preload will improve cardiac

output Intermittent pneumatic compression to

legs will improve venous return Use of alpha 2 agonist such as clonidine

or dexmedetomidine & or beta blocker reduces haemodynamic changes

Exaggerated in obese patients, ASA classII and III patients & in those with respiratory dysfunction

Intra-abdominal distension leads to a decrease in pulmonary dynamic compliance

1. increased IAP displaces the diaphragm upward 2. functional residual capacity and total lung

compliance decreases 3. Early closure of smaller airways, basal atelectasis 4. increased peak airway pressures 5. increase in minute ventilation required to maintain

normocarbia6. Increase in intra pulmonary shunting

Risk factor for RegurgitationIncreased intra-abdominal pressureDecreased lower esophageal sphincter

tone (if barrier pressure is increased>30cm of H2O)

Head down position

NG tube mandatory

Mesentric circulation: Reduced bowel circulation resulting in

decreased gastric intra mucosal pH Due to IAP, collapse of capillaries and

small veins, Reverse Trendelenburg position, Release of vasopressin all lead to decreased mesenteric circulation

Porto Hepatic circulation: Rise in IAP result in decreased total

hepatic blood flow due to splanchnic compression

Hormonal release (catecholamine, Vasopressin & Angiotensin lead on to overall reduction in splanchnic blood flow except for Adrenal glands

Increased IAP decreased RBF increased sympathetic activity elevated plasma Renin activity fall in filtration pressure fall in urine output

Increased IAP Increased lumbar spinal pressure Decreased drainage from lumbar plexus Increased ICP

Hypercapnia, high systemic vascular resistance and head low position combine to elevate intracranial pressure.

The induction of pneumoperitoneum itself increases middle cerebral artery blood flow

Increased IAP may lead to increased venous stasis

causing deep vein thrombosis especially in prolonged surgery

deep vein thrombosis prophylaxis should be done in such patients.

Continuous flow of dry gases into peritoneal cavity under pressure can lead to fall in body temperature.

(sudden expansion of gas produces hypothermia due to Joule Thompson effect)

0.30 C fall in core temperature/50 Lit flow of CO2

Activation of Hypo thalamo pituitary Adreno cortical Axis

Rise in ACTH, Cortisol and Glucogon

Altered glucose metabolism

Laparoscpic surgery is as stressful asconventional surgery

Head Down tilt - for pelvic and sub meso-colic surgery

HeadUp tilt - for supra mesocolic surgery

Lithotomy position - for gynecological procedures

Head-down position ▪ Endo-bronchial intubation▪ Promotes atelectasis ▪ Decreases FRC ▪ Decreases TLC ▪ Decreases pulmonary compliance

Head-Up position: favorable for respiration

Head up tilt----- Blood pooling Venous stasis Thrombo-embolism ↓ venous return ↓cardiac output → ↓ Blood Pressure

Head down Position: ▪ Increases CVP ▪ Increases cardiac output ▪ Increases cerebral circulation ▪ Increased ICP ▪ Increased intra-ocular pressure

Hyper extension of arm --- brachial plexus injury

Lithotomy position --- common peroneal injury

Due to trochar injuryPositioning and compression effectCVS and RS complicationsThermal injuriesGas embolism

Subcutaneous emphysema ▪ occur if the tip of the Veress needle does not

penetrate the peritoneal cavity prior to insufflation of gas.

▪ Occur in inguinal hernia repair, renal surgery▪ During fundoplication for hiatus hernia repair

Extraperitoneal insufflation, which is associated with higher levels of CO2 absorption than intraperitoneal insufflation, is reflected by a sudden rise in the EtCO2, excessive changes in airway pressure and respiratory acidosis

CO2 subcutaneous emphysema readily resolves after insufflation has ceased

Pneumothorax, Pneumomediastinum and Pneumopericardium

Patent pleuro-peritoneal channels Pleural injuries Ruptured emphysematous bullae

Pneumothorax, Pneumomediastinum and Pneumopericardium

Sudden hypoxia, rise in peak airway pressure, hypercarbia, haemodynamic alterations and

abnormal movement of the hemidiaphragm on laparoscopic view should raise a suspicion of pneumothorax

Recommended Guidelines Stop N2O Adjust ventilator settings to correct

hypoxemia If due to pleuro peritoneal channel route Apply PEEP Reduce intra-abdominal pressure Communicate with surgeon Avoid thoracocentesis unless necessary Avoid PEEP if there is rupture of

emphysematous bulla and thoracocentesis is mandatory

Most feared & fatal complication Seen frequently when laparoscopy is associated with

hysteroscopy Intra vascular injection of gas following direct trocar

placement into vessel Gas insufflation into abdominal organ

Suspicion of Gas Embolism Blood on aspiration from Vere’s needle Pulsation of flow meter pressure gauge Disappearance of abdominal distention despite

sufficient volume of gas

Depends on volume of air and rate of iv entry Rapid insufflation of gas into blood (2ml/kg) -> larger bubbles -Gas lock in RA & venacava -> Fall in cardiac output ->High pressure in RA -> Open foramen ovale ->Embolus in cerebral & coronary beds -> Paradoxical embolism

Detection of gas in right side of Heart –foamy blood aspirated in the central venous catheter

Recognition of physiological changes secondary to emboli: ▪ Tachycardia ▪ Cardiac arrhythmia ▪ Hypotension ▪ CVP rise ▪ Mill-wheel murmur ▪ Cyanosis ▪ Right heart strain pattern in ECG ▪ Pulmonary edema

Doppler & TEE ---- very sensitive (0.5ml/kg)

Immediate cessation of insufflation Release of pneumo-peritoneum Patient in head down and left lateral

decubitus (Durant’s) position Cessation of N2O Give 100% oxygen CVP insertion and aspiration of gas CPR help to fragment CO2 emboli into small

bubbles

Postoperative Pain abdominal and shoulder tip pain after

laparoscopic surgery Complete removal of the insufflating gas

is essential Infiltration of the portal sites with a local

anaesthetic reduces pain right-sided subdiaphragmatic instillation

with a local anaesthetic reduces shoulder tip pain

Post Operative Nausea & Vomiting (PONV)

Peritoneal insufflation, bowel manipulation and pelvic surgery are some of the causative factors

A meticulous anaesthetic technique along with antiemetics is helpful in reducing the incidence of PONV

J Emerg Trauma Shock. 2011 Apr;4(2):168-72.Comparison of ondansetron and combination of ondansetron(4mg) and dexamethasone(4mg) as a prophylaxis for postoperative nausea and vomiting in adults undergoing elective laparoscopic surgery.Bhattarai B, Shrestha S, Singh J.SourceDepartment of Anesthesiology, Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel; Kavre, Nepal.

Conclusion: Combination of ondanserton and dexamethasone is more effective in preventing post operative nausea vomiting in patients undergoing laparoscopic surgerythan ondansetron alone.

Am J Ther. 2011 Apr 23. [Epub ahead of print]A Randomized Double Blind Study to Evaluate Efficacy of Palonosetron(0.075mg) With Dexamethasone(8mg) Versus Palonosetron Alone for Prevention of Postoperative and Postdischarge Nausea and Vomiting in Subjects Undergoing Laparoscopic Surgeries with High Emetogenic Risk.Blitz JD, Haile M, Kline R, Franco L, Didehvar S, Pachter HL, Newman E, Bekker A.SourceDepartment of Anesthesiology, New York Uiversity Langone Medical Center, New York, NY.

Conclusion: There was no change in comparative efficacy over 72 hours, most likely due to the low incidence of PDNV in both groups.

Peritoneal cavity is expanded using abdominal wall lifter.

This avoids haemodynamic & respiratory repercussions of increased IAP

It increases technical difficulty

Anaesthetic Goals Accommodate surgical requirements and

allow for physiological changes during surgery.

Monitoring devices available for the early detection of complications.

Recovery from anaesthesia should be rapid with minimal residual effects.

The possibility of the procedures being converted to open laparotomy to be considered

Pre-operative assessment The cardiac and pulmonary status of all

patients should be carefully assessed Pre-medication ▪ Anxiolytics ▪ antiemetic ▪ H2 receptor blockers ▪ Gastro-kinetic drugs ▪ Preemptive analgesia with NSAIDs  ▪ Atropine to prevent vagally mediated

bradyarrhythmias

1.Routine Patient Monitoring Include Continuous ECG Intermittent NIBP Pulse oximetry (SpO2) Capnography (EtCO2) Temperature Intraabdominal pressure 2. Optional Monitoring Include Pulmonary airway pressure Oesophageal stethoscope Precordial doppler Transoesophageal echocardiography

VIGILANT ANAESTHESIOLOGIST

General anaesthesia

Preloading with crystalloid solution is recommended 

Preoxygenation During induction of Anaesthesia, avoid stomach

inflation tracheal intubation – mandatory PLMA  should only be used by experienced LMA

users  NG tube placement for Stomach decompression Catheterisation to empty  the urinary bladder

Maintenance of Anaesthesia

▪ intermittent positive pressure ventilation (IPPV) .▪ Normocarbia (34-38mmHg) to be maintained by

adjusting the minute volume ▪ The use of nitrous oxide during laparoscopic surgery

is controversial (bowel distension during surgery and the increase in postoperative nausea) . ▪ Halothane increases the incidence of arrhythmia  ▪ Isoflurane / sevoflurane comparatively better

Reversal of NM blockade

Recovery room -Post-op Period 1.Continue monitoring 2.Post-op pain relief 3.Post-op shivering 4.O2 thru’ Mask 5.Measures to Prevent pulmonary

atelectasis 6.DVT prophylaxis

▪ Epidural anaesthesia for outpatient gynaecological laparoscopic procedures to reduce complications and shorten recovery time after anaesthesia .

▪ not been reported for laparoscopic cholecystectomy or other upper abdominal surgical procedures except in patients with cystic fibrosis .

▪ The high block produces myocardial depression and reduction in venous return, aggravating the haemodynamic effects of tension pneumoperitoneum

Local anesthesia with IV sedationQuick recovery less PONVLess haemodynamic changesEarly diagnosis of complications

Peripheral nerve blocks Rectus sheath block Inguinal block Para vertebral block

Pre requisites: relaxed cooperative patient low IAP reduced tilt precise gentle surgical technique

Risk for post operative pulmonary complications can be minimised by meticulous pre

op.preparation. Procedure time should be minimized to less than

2hrs PFT,CXR,ABG, SpO2 in addition to history and

physical examination Cessation of smoking, adequate bronchodilators,

steroids and chest physiotherapy with incentive spirometry help to reduce post op pul c/o

Standard monitoring IAP less than 12mmHg GA with controlled ventilation Helium for pneumo peritonium Monitor peak airway pressure to avoid

barotraumas Minimal tilt Multimodal approach for P.O.analgesia to

avoid respiratory depression

Obesity is associated with Diabetes Mellitus, hypertension and

hypercholesterolemia, angina and sudden death. Life expectancy in obese patients is

shortened by as much as eight years.

Obesity is defined as a body mass index (BMI) >30kg/m2.

Laparoscopy is not contraindicated in healthy obese patients who experience reduced pain, faster recovery and fewer postoperative problems compared to laparotomy

Detrimental effect in respiratory mechanics is due to supine position and increased weight

Carbon dioxide production and oxygen consumption are increased.

Reduced chest wall compliance & decreased lung compliance.

Functional residual capacity (FRC) will be reduced 25 per cent in the supine position, with a further reduction of 20 per cent with Anaesthesia.

airway closure and hypoxemia, Increase in intrapulmonary shunting. Alterations to gastric function and drug

distribution.

Potential airway and intubation problems Difficulties may be encountered during

intravenous access, positioning, pneumoperitoneum induction, trocar access

In obese patients, the umbilicus is located 3-6cm caudal to the aortic bifurcation, making trocar placement more difficult.

.

Two tables may be necessary. Mechanical lifting devices, with extra padding should be available.

Monitoring equipment such as a large blood pressure cuff, compression lower extremity stockings and pneumatic boots should be available.

Intravenous access may need to be central rather than peripheral in some cases.

Positioning should include padded stirrups with extra padding, compression devices

Towels behind shoulder blades to elevate the head, facilitating intubation and airway access .

complications may be reduced by filling the peritoneal cavity with carbon dioxide (CO2) to a predetermined pressure level rather than to a preset volume

Tilt Test: Placing the patient in steep Trendelenburg for two to

five minutes following intubation and positioning, observing the patient’s cardiac and respiratory indices. Patients who remain Normotensive and maintain peak airway pressures at < 30-40mmHg during the Tilt Test before and after insufflation , the surgery is relatively straightforward, producing excellent results.

Postoperative Care: Early mobilisation and avoidance of the supine

position will facilitate early recovery. oxygen therapy Aggressive pulmonary care and positioning. Abdominal pain may restrict ventilation and

ambulation. analgesia is paramount. Obese patients must have sequential

compression devices on their lower extremities or

Prophylactic anticoagulation to prevent pulmonary emboli (five to 12 per cent obese patients)7.

Age related physiological and pathological changes and age related concomitant diseases

Narrow margin of safety decrease in organ reserve Lead to high incidence of Peri operative

complications

Positioning the patient: 1.Fragile osteoporotic & spondylytic

changes in vertebrae 2.Protect from nerve injury 3.Prevention of venous stasis 4.Careful tilting (increment of 5° )

During intra-op period: -CV to maintain EtCO2 – 35mm.Hg. - Isoflurane less arrhythmogenic - IAP maintained below 15mm.Hg - Atropine to counteract ref.vagal

tone - Monitor urine out put & Electrolytes - Careful titration of all anaesthetic

agents -

-During recovery— -Exaggerated hypotension on

correcting lithotomy - Expected delay in recovery Inc.sensitivity to drugs. Imp.metabolism Delayed excretion

Indications:AppendicectomyCholecystectomyOvarian cystecomy

Increased risk of acid aspiration Increased risk of abortion/

miscarriage / premature laborGreater distribution volume due to

increase in blood volumeMore prone to hypoxemia due to

decrease in FRC and increase in O2 consumption

Difficult airway due to wt. gain, soft tissue in the neck, breast enlargement, and laryngeal edema

Relatively safe in 8-24 wks of pregnancy.

Chances for damage to gravid uterus by Verees needle

Fetal acidosis common

Operation in 2nd trimester before 24 wks Tocolytics therapy if risk of preterm labor Open laparoscopy for abdominal access

(HASSON’S TECH) to avoid damage to gravid uterus

IAP less than 12mmHg Continuous Fetal heart monitoring with trans

vaginal USG PaCO2 to be maintained at normal levels with the

help of EtCO2 monitor/ABG Mechanical ventilation to maintain physiologic

maternal alkalosis (pH7.44) Pneumatic compression devices to calf muscles

to prevent DVT

Small abdominal surface and organs demand small telescopes for laparoscopy.

The abdominal surface / cavity ratio in infants and children is less than that of adults.

The abdominal wall in children is pliable and attention is needed while placing the cannulas and trocars to prevent intraabdominal injuries.

The trans umbilical open laparoscopic technique for insufflation under direct vision is recommended to prevent complications with veress-needle

Gasless laparoscopic surgery can now be performed in these children and smaller infants .

In infants less than 5 kg weight, peri umbilical area should not be used for port access because of risk of puncture of umbilical vessels.

Cold, non-humidified CO2 directly in to the abdominal cavity also contributes to a major risk of hypothermia

A fluid bolus of 20 ml.kg-1 can be used to offset hemodynamic effects

In neonates, the foramen ovale or the ductus arteriosus is potentially patent and may reopen during the procedure.

The pulmonary arterial resistance is relatively high, predisposing to reverse flow through a patent ductus arteriosus or foramen ovale.

There is a risk of reopening of right-to-left shunts,

cardiac insufficiency and gas embolism into the systemic circulation which may result in cardiac ischemia and neurological damage.

CO2 absorption is more intense and faster in infants

Volume of gas for creation of pneumo peritoneum

is less

IAP should be limited to 5 – 10 mm Hg in neonates

and infants and 10 – 12 mm Hg in older children.

risk of injuries to vitals is higher, so care is must.

Prone for hypothermia & PONV

CO2 peritoneum results in ventilatory /respiratory changes

PaCO2 rise will aggravate cardio respiratory disturbances

Increase in EtCO2 >25% later than 30mts after beginning, suspect CO2 sub.cut.emphysema

Haemodynamic changes decrease CO and this is more in haemo dynamically compromised patients

Preload augmentation, use of vaso dilators, clonidine and Dexmedetomedine, high dose opioids, & beta blockers – will attenuate pathophysiologic hemodynamic changes

In pregnancy, lap surgery can be safely performed before23 wks (avoid hypercarbia) & open laparoscopic approach to avoid injury to gravid uterus.

Gasless laparoscopy may be helpful but technical difficulty is more

Laparoscopy has proven benefits allowing quick recovery, shorter hospital stay, less p.o.pain

General anesthesia with controlled ventilation has proved to be clinically superior anesthetic technique

Improved knowledge of pathophysiology and good perimoperative monitoring permit safe management in patient with severe cardio respiratory disease

Laparoscopy  surgery    presents  new challenges to the anaesthesiologist. 

A thorough knowledge of the patho physiological changes during laparoscopy along with vigilant monitoring is the backbone for an uneventful and complete

success.