anaesthesia for laparoscopic sx

ANESTHESIA FOR LAPAROSCOPIC SURGERIES

Prepared & Presented By:Dr. ROSHANA MALLAWAARACHCHI

AIMS

To review the history of laparoscopic surgeries.

To discuss, briefly, the basic principles of laparoscopic surgeries.

To discuss the physiological consequences of laparoscopic surgeries.

To discuss the complications (management) of laparoscopic surgeries.

To discuss the anesthetic management of laparoscopic surgery.

HITORICAL NOTES

1980: Patrick Steptoe (UK): started laparoscopic procedures.

1983: Semm (German gynecologist): performed the first laporoscopic appendectomy.

1985: Erich Muhe (Germany): 1st reported lapaorscopic cholecystectomy.

1987: Ger: lap repair of inguinal hernia.

HISTORICAL NOTES (…CONTD.)

1987: Phillipe Mouret (France): 1st Laparoscopic Cholecystectomy using video technique

1988: Harry Reich: laparoscopic lymphadenectomy for t/t of ovarian cancer.

1989: Harry Reich: first laparoscopic hysterectomy using bipolar dissection.

1990: Bailey and Zucker (USA): laparoscopic anterior highly selective vagotomy with posterior truncal vagotomy.

ADVANTAGES OF LAPAROSCOPIC SURGERY

Less postoperative pain

Less postoperative pulmonary impairment

Less incidence of postoperative ileus

Shorter hospital stay

Earlier ambulation

Smaller surgical scars

LAPAROSCOPIC PROCEDURES (GENERAL) Cholecystectomy Vagotomy Appendectomy Colectomy Inguinal hernia repair Adrenalectomy Nephrectomy Prostatectomy Pancreatectomy

Bariatric surgery Nissen fundoplication Para-esophageal

hernia repair Splenectomy Liver resection Cystectomy with ileal

conduit

LAPAROSCOPIC PROCEDURES (GYNECOLOGIC)

Ectopic pregnancy Ovarian

cystectomy Reversal of

ovarian torsion Salpingo-

oophorectomy Hysterectomy

Myomectomy Sacrocolpopexy Lymphadenectomy Lymphadenectomy

, staging Ablation of

endometriosis

SURGICAL STEPS

Introduction of ‘Veress Needle’

Creation of pneumoperitoneum

Electrocautery dissection

GASES USED TO CREATE PNEUMOPERITONEUM: WHY IS CO2 PREFERRED??

HeliumInsoluble, gas embolism

Argon

N2O: Supports combustion, diffuses into the bowel, PONV

CO2: Soluble in blood, Risk of gas embolus is reduced. Safe during electrocautery (Non-flammable) Can be easily eliminated through the lungs Rapidly absorbed into the bloodstream Inexpensive

PROPERTIES OF IDEAL GAS FOR INSUFFLATION

Colorless

Limited systemic absorption across the peritoneum

Limited systemic effects when absorbed.

Rapid excretion if absorbed

Incapable of supporting combustion.

High solubility in blood.

Limited physiological effects with intravascular systemic embolism

PHYSIOLOGICAL EFFECTS OF LAPAROSCOPY

Minimally invasive surgery is not minimally stressful!

MAJOR FACTORS RESPONSIBLE FOR ALTERATION IN PHYSIOLOGY

Pneumoperitoneum

Positioning

Systemic absorption of Carbon dioxide

EFFECT OF PNEUMOPERITONEUM (MECHANICAL EFFECTS)

RESPIRATORY & VENTILATORY CHANGES

Increased Intra-abdominal pressure

Upward displacement of diaphragm/Impaired diaphragmatic movements

Reduced lung compliance & FRCIncreased airway pressure & barotrauma

V/Q mismatch with hypoxemia & hypercarbiaCompression of basilar lung segments &

atelectasis

HEMODYNAMIC CHANGES

↑Intra-abdominal Pressure

↓Venous return & ↑SVR

↓ Cardiac Output & Cardiac Index

CNS

1) ↑ Intrathoracic pressure2) ↑ PaCO2 & ↑CBF

3) Compression of IVC, ↑ lumbar spinal pressure &↓ CSF drainage

↑ ICP

HEPATOPORTAL

? ↓ Gastrointestinal (Splanchnic) blood flow Mechanical compression ADH Superior mesenteric artery

constriction

? Maintained Splanchnic blood flow Hypercarbia Vasodilation

RENAL

Decrease in renal blood flow when IAP >15 mmHg Decrease in GFR Decrease in urine output Decrease in creatinine clearance Decrease in sodium excretion Potential for volume overload in the face of

excessive fluid administration.

LOWER LIMB

1) ↓ Femoral venous blood flow

2) Pooling of blood (Reverse Trendelenberg position)

↑DVT

EFFECT OF PNEUMOPERITONEUM ON PHARMACOKINETICS

Prolonged T1/2 of drugs eliminated by liver (reduction of hepatic perfusion)

Reduced Clearance of drugs eliminated through kidneys (reduced creatinine clearance and urine flow)

NEUROHUMORAL RESPONSES

RAA system activation (↑ renin, ↑ angiotensin, and ↑ aldosterone)

Sympathetic system activation (↑ catecholamines)

EFFECT OF POSITIONING

Friedrich Trendelenburg 1844-1924

EFFECTS OF POSITIONING

Position varies according to the anatomical site of operation Trendelenberg position

Pelvic procedures

Reverse Trendelenberg position

Supremesocolic procedures (e.g., Cholecystectomy)

Associated changes are related to: Degree of head-down/up

tilt Patient’s age Intravascular volume

status Associated cardiac

disease Ventilation techniques Anesthetic drugs

EFFECTS OF TRENDELENBERG POSITION Cardiovascular System

↑ CVP & CO Baroreceptor reflex vasodilation and

bradycardia Usually insignificant in healthy patients

Patients with coronary heart disease with poor left ventricular function - ↑ central blood volume, and pressure changes maybe harmful.

EFFECTS OF TRENDELENBERG POSITION Respiratory System

Facilitates the development of atelectasis FRC, total lung volume, and pulmonary

compliance is reduced.

CNS ↑ CBF

↑ ICP ↓ Venous return

EFFECTS OF REVERSE TRENDELENBERG POSITION

Cardiovascular System Venous return thus reducing CO and MAP

(compounded by the pneumoperitoneum) Venous stasis occurs in the legs

Respiratory System Increased FRC

EFFECTS OF CO2 INSUFFLATION

Direct Effects: Hypercarbia, Acidosis Decrease in HR, contractility, and SVR.

Indirect Effects (stimulation of SNS) Increase in HR, contractility, and SVR.

Premature ventricular contractions

Bradydysrhythmias

Asystole

COMPLICATIONS OF LAPAROSCOPY WITH RELEVANCE TO ANESTHESIA

Cardiovascular: Hypotension, hypertension, tachycardia, bradycardia, dysrhythmias,

asystole Pulmonary:

Hypercapnia, hypoxemia, atelectasis, barotrauma Related to gas insufflation

Subcutaneous emphysema, gas embolism, pneumothorax, pneumomediastinum, pneumopericardium, extreme CO2 absorption

Surgical Hemorrhage, damage to hollow viscera, damage to nerves

Mechanical Damage to nerves or eyes (positioning and draping), dislodgement

of ET tube with endobronchial intubation Miscellaneous:

Hypothermia, nausea and vomiting, hyperkalemia, renal failure, increased risk of regurgitation

Foramen Bochdalek

Foramen of Morgagni

Paraesophageal hiatus

Subcutaneious Emphysema

Subcutaneous Emphysema

GAS EMBOLISM: DETECTION

Fall in ETCO2 Dysrhythmias (bradycardia, tachycardia,

asystole) Hypotension (decreased left ventricular filling) Fall in arterial oxygen saturation Increased CVP and venous congestion ECG evidence of acute right heart strain Mill-wheel murmur Precordial Doppler, TEE, Transthoracic

echocardiography

GAS EMBOLISM: TREATMENT

Stop gas insufflations immediately Increase inspiratory O2 concentration to 100%

and hyperventilate Position patient head down, left lateral

decubitus Attempt intracardial gas aspiration if CVP

present Give inotropes to support right ventricle Treat severe hypotension with vasopressors CPR for asystole

DYSRHYTHMIAS

Tachycardia, bradycardia, asystole

Identify the cause

Stop gas insufflation

Consider Atropine (may need to give undiluted atropine)

Don’t delay CPR

ENDOBRONCHIAL INTUBATION

Carina shifts upwards with creation of pneumoperitoneum Exaggerated by positioning (head down)

Check tube position frequently

HYPOXEMIA Pre-existing conditions: morbid obesity, COPD

Hypoventilation: positioning, pneumoperitoneum, ET tube obstruction, bronchospasm, inadequate ventilation, gas embolism.

Intrapulmonary shunting: decreased FRC, endobronchial intubation, pneumothorax, atelectasis.

Decreased Cardiac Output: hemorrhage, dysrhythmias, myocardial depression.

Technical equipment failure: circuit disconnection, delivery of hypoxic gas mixture.

HYPERCARBIA

Excessive absorption of CO2 Hypoventilation Increased dead space CO2 embolism Pneumothorax, pneumomediastinum,

pneumopericardium Subcutaneous emphysema Exhausted CO2 absorber Malignant hyperthermia

ANESTHESIOLOGICAL CONTRAINDICATIONS OF LAPAROSCOPY

Congestive heart disease (NYHA II-IV) Ischemic heart disease Obstructive and restrictive pulmonary diseases Morbid obesity Pregnancy Patent foramen ovale Huge organomegaly Moderate to severe ascites Right-to-left shunt

ABSOLUTE CONTRAINDICATIONS

Acute or recent MI

Blood dyscrasias

Late 2nd trimester of pregnancy

Uncompensated COPD

Hiatus hernia

CONDUCT OF ANESTHESIA

Pre-anesthetic check-up & Pre-op advice

History, physical examination, risk assessment.

Premedication: H2-blocker, Anxiolytic (midazolam/diazepam)

CONDUCT OF ANESTHESIA

Goals: IAP: 12 – 15 mmHg (don’t allow to rise >20 mmHg) Airway pressure <40 cmH2O (20 – 30) EtCO2 ~ 35 mmHg Maintain BP and HR.

Give attention to Prevent Acid Aspiration ET tube displacement Rhythm changes esp. at the time of gas insufflation PONV prophylaxis Post-operative pain management

Patient may be anxious

Duration may be long

Trendelenburg position (with pneumoperitoneum) may cause respiratory compromise and dyspnea in the awake patient

Muscle relaxation is invariably needed.

LMA, & spontaneous breathing not recommended.

Induction: Injection Pethidine 0.5 – 1 mg/kg; then inj Propofol (1.5 – 2 mg/kg) or STP (5 mg/kg); Succinylcholine (vecuronium, rocuronium, cisatracurium) + Inj Dexamethasone 4 mg iv for PONV prophylaxis

Intubation: appropriate size cuffed ET tube (LMA not recommended). NG or OG tube insertion and aspiration of stomach content (air)

Maintenance: Isoflurane (or TCI of TIVA) + O2 + Muscle relaxant ;

Ventilation: O2 + IPPV (spontaneous ventilation not recommended) adjusted to eliminate CO2

End of the Sx: Give inj ondansetron 4 mg; stop isoflurane when instruments are removed; slightly reduce ventilation, allow the patient to breathe spontaneously (but avoid hypoventilation); Reversal agent

Halothane (+ fentanyl) not recommended.

Extubation

Watch for facial edema

Watch for subcutaneous emphysema

Inspect oropharynx

POSTOPERATIVE MANAGEMENT

Issues:

Pain: wound/ right shoulder

PONV

PROTOCOL FOR POSTOPERATIVE PAIN RELIEF

Preoperative administration of a non-opioid analgesic (e.g. NSAID, Paracetamol)

Pre-incisional infiltration of trocar insertion sites with local anesthetics (e.g. 40 ml bupivacaine 0.25%, lidocaine 0.5%)

Rescue medication with small doses of an opioid (e.g. morphine)

Treat postoperative shivering with clonidine or pethidine.

PONV

Incidence as high as 42%.

Inj Dexamethasone 4 mg iv at the time of induction.

Inj Ondansetron 4 mg iv at the end of surgery.

Third anti-emetic for rescue therapy.

Adequate pain control.

Recent Advances

GASLESS LAPAROSCOPY

SINGLE-PORT LAPAROSCOPIC SURGERY

Less postoperative pain, less blood loss, faster recovery time, and better cosmetic resultsDrawbacks - increased operative time

Thank You