58f6anesthesia For Laparoscopic Surgeries.pptx

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Anesthesia For Laparoscopic Surgeries Prepared & Presented By: Hem Raj Paneru MD 2nd Year, Anesthesiology Moderator: Prof. Dr. B B Singh NAMS 16th Magh, 2067 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 • Salpingooophorectomy • Hysterectomy • Myomectomy • Sacrocolpopexy • Lymphadenectomy • Lymphadenectomy, staging • Ablation of endometriosis Surgical Steps • Introduction of ‘Veress Needle’ • Creation of pneumoperitoneum • Electrocautery dissection • Helium • Argon Gases used to create pneumoperitoneum: Why is CO2 preferred?? Insoluble, gas embolism • N2O: Supports combustion, diffuses into the bowel, PONV • N2 • Air • CO2: – Safe during electrocautery – Can be easily eliminated through the lungs – Rapidly absorbed into the bloodstream 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 excursion Reduced lung compliance, FRC Increased airway pressure & barotrauma V/Q mismatch with hypoxemia & hypercarbia Compression of basilar lung segments & atelectasis Hemodynamic Changes ↑IAP ↓Venous return & ↑SVR ↓ Cardiac Output & Cardiac Index CNS 1) ↑ Intrathoracic pressure 2) ↑ PaCO2 & ↑CBF 3) Compression of IVC, ↑ lumbar spinal pressure &↓ CSF drainage ↑ ICP Hepatoportal • ? ↓ 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 • Associated changes are to the anatomical site of related to: operation – Degree of head-down/up – Trendelenberg position • Pelvic and inframesocolic procedures – – – – – – Reverse Trendelenberg position • Supremesocolic procedures (e.g., Cholecystectomy) 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 deleterious 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 Paraesophageal hiatus Foramen of Morgagni Subcutaneous Emphysema Subcutaneious Emphysema Gas Embolism: Detection • Fall in ETCO2 • Dysrhythmias (bradycardia, tachycardia, VPCs, 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, VPCs, 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 Unidirectional valve dysfunction 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. Prevent Acid Aspiration ET tube displacement Rhythm changes esp. at the time of gas insufflation PONV prophylaxis Post-operative pain management • Give attention to GETA with IPPV The “Gold Standard” • 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: 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 Do we need ABG??? When To Perform ABG? • After 30 minutes of pneumoperitoneum??? – During laparoscopy an unsteady sate of CO2 level exists between body compartments. – Rate of rise of PCO2 is greatest during the first 20 – 30 minutes. – After 20 – 30 minutes, new equilibrium levels are reached between the different compartments, and the rate of PCO2 rise is slower. 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 ABDOLIFT Gasless Laparoscopy Laparoscopic Cholecystectomy Under Regional Anesthesia • • • • • 12 patients, ASA I & II 4 ml 0.5% hyperbaric bupivacaine + 150µg Morphine Minimal operating table tilt CO2 pneumoperitoneum IAP <10 mmHg Ambulatory Laparoscopic Cholecystectomy • ASA I & II patients • Appropriate social conditions • Uncomplicated surgery • Minimal post-operative analgesia requirements • No PONV Thank You