Anaesthesia for lap chole

Anaesthesia for lap chole

1. Anaesthetic Considerations For Laparoscopic Cholecystectomy Dr. Suresh Pradhan

2. Introduction the development of “minimally invasive surgery” or “minimal access surgery” has revolutionized the field of surgery Carl Langenbuch : 1 st successful cholecystectomy in 1882 Philippe Mouret : Introduced Laparoscopic Cholecystectomy in 1987

3. Advantages minimizes surgical incision and stress response decreases postoperative pain and opioid requirements preserves diaphragmatic function improves postoperative pulmonary function earlier return of bowel function

4. Advantages Contd … fewer wound-related complications earlier ambulation shorter hospital stays early return to normal activities and work reduces health costs

5. Minimally Invasive surgery may not be Minimally stressful to the patient !!!

6. The Pneumoperitoneum and the patient positions required for laparoscopy induce pathophysiologic changes that complicate anaesthetic management.

7. PNEUMOPERITONEUM insufflation of the peritoneal cavity with gas CO 2 - used most commonly CO 2 – non combustible - allows the use of Diathermy or Laser highly Soluble – rapid elimination of absorbed gas colourless non – toxic less expensive

8. PNEUMOPERITONEUM CO 2 is insufflated at the rate of 4-6L/min to the pressure of 10 -15 mm Hg Pneumoperitoneum is maintained by a constant gas flow of: 200 – 400 ml / min

9. Gases used to create Pneumoperitoneum Gas Advantages Diaadvantages Air, O 2 Easily avialable , inexpensive , limited physiological effect Support combustion N 2 Does not support combustion , poorly absorbed , avoids hypercapnia Low blood solubility –dangerous consequences if gas embolization occurs N 2 O May be benificial in patients undergoing procedures under regional anaesthesia Supports combustion Helium/Argon Poorly absorbed – avoids hypercapnia , does not supports combustion Low blood solubility –dangerous consequences if gas embolization occurs. Not cost effective CO 2 Does not support combustion Absorbed in large quantities from the peritoneal

10. Gasless Laparoscopy utilizes an abdominal wall lift system to achieve surgical space avoids the physiologic alterations due to carboperitoneum although safe, this method has not been accepted in routine clinical practice because it increases operating time and surgical costs without improving clinical outcomes

11. Gasless Laparoscopy

12. PHYSIOLOGICAL CHANGES FROM PNEUMOPERITONEUM and POSITIONING

13. the physiologic consequences of laparoscopy can be complex and depend on the interactions between: patient’s pre-existing cardiopulmonary status, and surgical factors magnitude of IAP degree of CO 2 absorption alteration of patient position type of surgical procedure

14. the various physiological changes can be studied under: Respiratory and Gas exchange effects Haemodynamic Changes/ Cardiovascular effects Effects in Regional Perfusion

15. Respiratory Complications 1. Carbon dioxide subcutaneous emphysema—due to extra-peritoneal insufflation 2. Pneumothorax, pneumomediastinum , pneumopericardium, capnothorax 3. Endobronchial intubation—due to cephalad movement of the diaphragm 4. Gas embolism 5. Aspiration of gastric contents

16. RESPIRATORY CHANGES pneumoperitoneum -cephalad displacement of diaphragm -decreased thoraco-pulmonary compliance by 30 – 50% FRC and TLC decreases risk of atelectasis, intrapulmonary shunting -hypoxemia increase in airway pressure-- increase resistance--increase work of breathing

17. RESPIRATORY CHANGES risk of increased physiological dead space, V/Q mismatch and shunting unlikely with IAP 14mm Hg and Head up position of 10 – 20 degrees but may be of concern in patients with respiratory and cardiovascular diseases

18. RESPIRATORY PROBLEMS ENDOBRONCHIAL INTUBATION cephalad displacement of the diaphragm due to pneumoperitoneum can result into cephalad displacement of carina decreased oxygen saturation (SaO 2 ) increase in the airway pressure

19. RESPIRATORY PROBLEMS INCREASE in PaCO 2 absorption of the gas from the peritoneal cavity depends on : diffusibility absorption Area perfusion of the walls of the cavity duration of Surgery

20. .. Increase in PaCO 2 PaCO 2 progressively increases to reach the plateau 15 – 30 mins following the insufflation if significant increase after this period; other causes like CO 2 subcutaneous emphysema should be ruled out during deflation; CO 2 accumulated in the collapsed peritoneal capillaries reach the systemic circulation causing transient increase in PaCO 2

21. .. End tidal CO 2 tension (P ET CO 2 ) Normal P ET CO 2 5% ( 35 – 37 mm Hg) Gradient between PaCO 2 and P ET CO 2 ( Δ a –ETCO2): 5-6 mm Hg

22. .. Increase in PaCO 2 ( Δ a –ETCO2) : No significant change

23. … Measures for maintaining Normocapnia MINUTE VENTILATION V T RR Increasing VT may worsen the hemodynamic changes.

24. RESPIRATORY PROBLEMS CO 2 Subcutaneous Emphysema complication of accidental extraperitoneal insufflation any increase in P ET CO 2 after its plateau : suspect it readily resolves after the insufflation is stopped

25. .. CO 2 Subcutaneous Emphysema

26. RESPIRATORY PROBLEMS PNEUMO – THORAX/ PERICARDIUM/ MEDIASTINUM embryonic remnants – communication channels ; which can open up when intraperitoneal pressure rises pneumothorax may also occur due to defects in the diaphragm/ weak points in Aortic or Oesophageal hiatus / (Iatrogenic – Pleural tears)

27. .. CAPNOTHORAX reduced thoracopulmonary compliance increased Peak Airway Pressure PaCO 2 and PETCO 2 also increases Tension Pneumothorax – Hemodynamic Changes and Desaturation

28. .. CAPNOTHORAX PNEUMOTHORAX Due to CO 2 RUPTURED BULLAE VENTILATION WITH PEEP THORACOCENTESIS Mandatory Resolution Occurs ~ 30 – 60 mins

29. RESPIRATORY PROBLEMS GAS EMBOLISM rare but most dangerous accidental needle or trochar placement into a vessel

30. … Gas Embolism Earliest changes: Increased mean Pulmonary artery Pressure Doppler sound changes Tachycardia Hypotension Cyanosis Millwheel murmurs Increased CVP ECG : Rt. Heart strain pattern Capnography : PETCO 2 Decreases !! Aspiration of Air or Foamy Blood from the Central Line establishes diagnosis

31. … Gas Embolism stop insufflation and release pnemoperitoneum discontinue N 2 O and allow 100% O 2 DURANT Position : Steep head down and Lt Lateral hyperventilation : to increase CO 2 elimination CPR if required : also fragments the CO 2 emboli into small bubbles central venous line / Pulmonary artery catheter – Aspiration of the gas hyperbaric O 2 if cerebral embolism suspected

32. Respiratory Complications: Summary

33. HAEMODYNAMIC PROBLEMS DECREASED CARDIAC OUTPUT significant haemodynamic alterations occur after IAP > 10 mm Hg and and is proportional to IAP changes Cardiac Output falls by 10 - 30% due to peritoneal insufflation whether the position is head up or down

34. .. Decreased Cardiac Output Mechanism : increased IAP( >15mm of Hg) and Vena- caval compression head up position: pooling of the blood in venous system increased Venous Resistance

35. .. Decreased Cardiac Output fall in CO attenuated by increasing circulating volume before pneumoperitoneum is created slight head down position before insufflation sequential Pneumatic compression devices leg elastic bandages

36. HAEMODYNAMIC PROBLEMS INCREASE IN SVR ( AFTERLOAD ) due to release of neuro-humoral factors eg ; Catecholamines , Vasopressin , RAAS the increase in systemic vascular resistance explains why the arterial pressure increases but the cardiac output falls

37. HAEMODYNAMIC PROBLEMS

38. HAEMODYNAMIC PROBLEMS

39. HAEMODYNAMIC PROBLEMS Increased IAP and Head up position results in Venous Statis , may predispose to the development of thromboembolic complications

40. Effect of pneumoperitoneum on Regional Perfusion 1. Renal effects : decrease in renal blood flow -- glomerular filtration rate due to the reduction in cardiac output-- reduction in intra-operative urine output 2. Splanchnic and hepatic blood flow : unclear 3. Gastrointestinal effects : Raised intra-abdominal pressure can predispose the patient to regurgitation and aspiration

41. 4 . Neurologic effects : hypercapnia, head-low position, and elevated systemic vascular resistance ---- increase in ICP with a resultant decrease in cerebral perfusion pressure 5. Ocular effects : increase in IOP 6. Neuroendocrine effects : Increased levels of stress hormones. Increase in ADH and aldosterone levels

42. TROCHAR RELATED PROBLEMS Trochar Insertion TRAUMA VAGAL OVERSTIMULATION STOMACH BOWEL LIVER VESSELS – Hemorrhage ! Due to sudden stretching of the Peritoneum. - Bradycardia - Arrhythmias - Asystole

43. Problem with position 1. Reverse Trendelenburg (head up): blood pooling in the lower extremities--- Preload is decreased, resulting in lowered pressure (MAP) increase the risk of venous thrombosis and pulmonary emboli. however, pulmonary function is improved

44. 2. Trendelenburg position (head down): cardiac output and central venous pressure increase decreased functional residual capacity, decreased total lung capacity, and decreased pulmonary compliance, predisposing the patient to developing atelectasis endobronchial intubation

45. Problem with positioning 3. Nerve injuries : ulnar nerve- when the upper limbs are adducted against the body brachial plexus- when using shoulder braces common peroneal nerve- in the lithotomy position in steep head-up position, the patient must be securely strapped to prevent the patient from slipping off the table access to intravenous lines may be a problem, and the use of extension tubing may be needed

46. POST OPERATIVE PAIN Infiltration of the port sites with Local Anaesthetics Intraperitoneal infiltration - in the gallbladder bed Encourage the surgeon to expel as much as intra peritoneal gas to reduce post op pain Preoperative NSAIDS decrease post op pain and also reduce the opioid requirements TAP block POST OPERATIVE PAIN Parietal Abdominal wall VISCERAL Biliary Colic REFERRED Shoulder tip pain

47. POST OPERATIVE NAUSEA VOMITING High Incidence of PONV following Laparoscopic surgery Perioperative Opioids Use of N 2 O ? PROPOFOL used for Induction Intraoperative Administration of Droperidol / 5 – Hydroxytryptamine Type 3 Antagonists ( Ondansetron, Granisetron ) reduces the incidence of PONV

48. Laparoscopic Cholecystectomy – Anaesthetic Considerations Techniques: GA with ET intubation, muscle relaxation and controlled ventilation is considered the safest technique: Protects airway Enables PaCO 2 control Better Surgical exposure

49. Laparoscopic Cholecystectomy – Anaesthetic Considerations GA with LMA Proseal LMA provides better seal pressure and permits drainage of gastric secretions better avoided if history of reflux or in obese patients or prolonged surgery expected

50. Laparoscopic Cholecystectomy – Anaesthetic Considerations regional techniques generally avoided as higher level of blocks required Epidural/spinal : successfully performed esp. in cases of COPD patients hemodynamic effects not adequately studied

51. Controlled versus spontaneous ventilation Controlled ventilation Good airway seal risk of aspiration is decreased allows for controlled ventilation to prevent hypercapnia allows abdominal wall relaxation and muscle paralysis, and ensures adequate oxygenation Good surgical vision Increased Stress response to intubation and sore throat Spontaneous ventilation No seal of airway Increase level of CO2 Chances of hypoxemia high High chances of aspiration pneumonia No stress respone and sore throat Chances of instrumental related injury

52. Pre – Operative Considerations… Patients are usually “ Fat Female Fertile Forty Fair ”

53. Pre – Operative Considerations… ABSOLUTE CONTRAINDICATION Uncontrolled Coagulopathies End Stage Liver Disease Severe Obstructive Pulmonary Disease Congestive Heart Failure (EF <20%) Shock Significantly raised ICP Retinal detachment Right to left shunt

54. Pre – Operative Considerations… POTENTIALLY DIFFICULT (Previous Relative Contraindications) Acute Cholecystitis Empyema / Gangrene of Gallbladder Pregnancy Obesity Ventriculo – Peritoneal Shunt Previous abdominal surgeries Biliary Enteric Fistula

55. Preoperative assesment History- comorbid condition , medication , surgical history, personal history, family history General physical and systemic examination Investigation: hemogram, liver and renal function tests, chest X-ray and ECG if history or ECG is suggestive of cardiac disease-- 2D-Echocardiogrpaphy or stress testing is indicated Deep venous thrombosis prophylaxis with heparin or low-molecular weight heparins should be considered

56. Preoperative consideration Monitoring: -electrocardiogram, noninvasive arterial pressure monitor, airway pressure monitor, pulse oximeter, ETCO2 concentration monitor, peripheral nerve stimulator (optional) and core body temperature monitoring continuous arterial pressure, cardiac filling pressures and blood gases monitoring --- For patients with compromised cardiopulmonary function

57. Pre – Operative Considerations… Premedication with : (Increased risk for aspiration) H 2 Antagonists/ Proton Pump Inhibitors Metoclopromide Esp. in Obese patients Premedications with analgesics – Paracetamol or NSAIDS – Better post operative pain control all patients have risk of conversion into open procedure

58. Pre – Operative Considerations… Hypovolemia should be avoided. Pre- operative fluid deficits must be corrected Preloading – decrease the fall in the cardiac output. Adequate level of anaesthesia / Premedication with Vagolytics – May prevent vagal stimulation

59. Peri - operative considerations.. Choice of anaesthetic technique – GA + ETT safest Propofol as inducing agent – less incidence of Post – op nausea and vomiting. Avoid gastric distention during bag and mask ventilation. N 2 O : Gastric distention / Post op nausea vomiting Use of gastric tube to deflate the stomach.

60. Peri - operative considerations.. Increased CO 2 absorption will require increased minute ventilation. ( VT increase may increase hemodynamic changes / Requires RR control ) normocarbia desirable if difficult, may require intermittent release of the insufflating gas possible causes of Hypoxemia during the surgery !!

61. Intraoperative complication creation of pneumoperitoneum through intraperitoneal CO 2 insuflation , patient positioning, and surgical instrumentation - cardiopulmonary compromise, renal dysfunction, and hypothermia Surgical complications - subcutaneous emphysema, capnothorax , capnomediastinum, capnopericardium, gas embolism, acute hemorrhage, and bowel or bladder perforation.

62. Causes of Hypoxemia during laparoscopy

63. DIFFERENTIAL DIAGNOSIS OF CARDIOVASCULAR COLLAPSE DURING LAPAROSCOPY

64. DIFFERENTIAL DIAGNOSIS OF HYPERCARBIA DURING LAPAROSCOPY

65. PREVENTION OF CARDIOPULMONARY CHANGES IN PATIENTS WITH SIGNIFICANT CARDIOPULMONARY DISEASE

66. Peri - operative considerations.. Anti – emetics Prophylactically given during the end of the surgery 5 – HT 3 Antagonists Check for endobronchial intubation after gas insufflation and after positional changes

67. Post Operative Considerations … Encourage the surgeon to expel as much of intra- peritoneal gas following surgery. Pain : Intra- peritoneal and port sites infiltration with local anaesthetics Continuation of antiemetics and analgesics. Increased O 2 demand after surgery (PaO 2 decrease).

68. Extubation prolonged laparoscopy in the Trendelenburg position requires special considerations delay extubation if the patient has edema, venous congestion, and duskiness of the head and neck sometimes the tongue becomes edematous

69. Thank You!!!