Basics of Laparoscopy Gyn

setup
ergonomics
port placement
complications

1. BASICS OF LAPAROSCOPY PRESENTER :DR SHRUTHI SHIVDAS MODERATOR: PROF DR PALLAVI VR DEPT OF GYN ONCO, KMIO, B’LORE Dr Shruthi Shivdas

2. CONTENTS BASIC SET UP – laparoscopic tower shelf ERGONOMICS PORT PLACEMENT ENTRY ENERGY DEVICES COMPLICATIONS STERILISATION Dr Shruthi Shivdas

3. Laparosopic tower The laparoscopic "tower" Shelf contains Imaging system Insufflator Electrocautery unit In this manner, the surgeon can rapidly assess any equipment problems ( eg. loss of insufflation pressure) for rapid trouble-shooting.  Electrocautery unit should ideally be kept separately to avoid antenna coupling. Dr Shruthi Shivdas

4. Imaging System monitor Camera box Light Source Dr Shruthi Shivdas

5. LIGHT source & cable Three types of light source are in use today: 1. Halogen light source 2. Xenon light source 3. Metal halide light source Xenon - Best illumination by powerful sources. Minimum heat conduction to the telescope body- “cold light” Light cables transmit the output from the light sources to the telescope. 1. Fiber optic cable 2. Liquid crystal gel cable. White balance by making sure white is correctly identified so that all the colors through the spectrum are correct. Dr Shruthi Shivdas

6. Light cable Dr Shruthi Shivdas

7. Telescope -diameter 10mm-Most commonly used for operative as well as Diagnostic purpose. 5mm- Mainly used for diagnostic purpose , can be used for operative purpose. < 5mm- Very delicate MINIlaparoscopy mainly used in children (1.1mm) Diagnostic purpose also in operative purpose. With contemporary technology, 5-mm lenses are useful but provide slightly less capacity for light transmission and may appear dark. The darkness of the 5-mm lens may be accentuated by blood in the operative field as blood further absorbs light. Dr Shruthi Shivdas

8. Telescope -ANGLES Straight/forward view with - 0 degree Angled at -25 to 30 or 45 to 50 degrees. With a 0 degree lens, the lens is flat and rotating the laparoscope does not alter the angle of vision; better for panaromic vision. Sufficient for diagnostic procedures. Angled lenses provide additional optical versatility by giving the operative team the ability to look at the surgical field with an angle up to either 30 degrees or 45 degrees by rotating the laparoscope; Especially useful for viewing underlying areas under difficult anatomical conditions e g: study of adhesions, ovarian surfaces ,while sealing uterine vessels, PLND Dr Shruthi Shivdas

9. ergonomics Dr Shruthi Shivdas

10. Tower shelf- straight line principle The laparoscopic "tower" should be straight ahead of the surgeon and in line with the forearm–instrument motor axis. It should be positioned lower than the surgeon's eye level to avoid neck extension. The most comfortable viewing direction is approximately 15° downward. Dr Shruthi Shivdas

11. TABLE HEIGHT Proper table height keeps the surgeon's arms and elbows adducted at his/her side at all times, which makes operating more comfortable. This is especially true for intracorporeal suturing where maximum range of motion is imperative. Dr Shruthi Shivdas

12. SURGEON’s stance Viewing distance is highly dependent on monitor size. Keeping monitor too close leads to extensive accommodation of the eyes and contraction by the extraocular muscles and eye fatigue. Keeping it too far leads to staring and loss of detail, eyestrain. The distance of the monitor from the surgeon also impacts on eyestrain.; preferably between 60 – 80 cm Dr Shruthi Shivdas

13. The camera-man Having the cameraman and the surgeon standing on the same side of the patient, the surgeon is prevented from working in "reverse" or at an angle. For pelvic laparoscopic procedures,the surgeon typically stands on the patient's left side and the assistant stands on the patient's right side Dr Shruthi Shivdas

14. Cords & Tubings To minimize tangling, the surgeon should keep only enough cord length for each instrument without excess. The suction-irrigation tubing, bipolar cautery cord, surgical energy device cords such as the harmonic scalpel cord or LigaSure cord should run off the head of the bed away from the surgeon.  Once the surgical team is pleased with trocar deployment and the access for surgery, the insufflation tubing should be placed on any trocar other than the camera trocar , which minimizes its cooling effect and consequent lens fogging. Dr Shruthi Shivdas

15. Operative setup Camera man TOWER Dr Shruthi Shivdas

16. Dr Shruthi Shivdas

17. Foot Pedals Best to use hand controls when possible. Pedals should be placed near the foot and aligned in the same direction as the instruments, toward the target quadrant and laparoscopic monitor,so that the surgeon need not twist his / her body or leg. A pedal with a built‐in foot rest is preferable, to avoid the surgeon having to keep the foot in air in between activations. X Dr Shruthi Shivdas

18. ERGONOMICS SURGEON’S STANCE Straight Line Principle Low Lying Table Below Elbow Gaze Down View PORT POSITIONING Triangulation if ipsilateral Baseball Diamond if contralateral Manipulation Angle Azmuth Angle ElevationAngle Dr Shruthi Shivdas

19. PORT positioning Dr Shruthi Shivdas

20. LATERALITY of the lap surgeon CONTRALATERAL IPSILATERAL Dr Shruthi Shivdas Baseball diamond Concept/ triangulation Triangulation Sectorization

21. Generally, all laparoscopic instruments should behave like type 1 lever ( half of the instruments should be in and half out). It means fulcrum in center and load is equal and opposite to the force applied.  If the port is very close to the target of dissection, the maximum length of the instrument is outside ( type 2 lever), elevation angle will be 90 degrees then surgery cannot be performed as an instrument will not lift the tissue; which results in tissue tear and avulsions.  If the port is very far from the target of dissection (type 3 lever), instrument has to be pushed too in to reach target; elevation angle will be less than 10 degrees then the handle of the instrument will touch the body of the patient; the maximum length of the instrument is inside the body which results in overshooting. Ideally 60 Dr Shruthi Shivdas

22. Dr Shruthi Shivdas

23. Points for secondary ports/working ports (BASEBALL) STEP 1 : OPTIMAL AREA For optimal performance, half to 2/3 of instrument should be inside abdomen. So adult instrument, (36 cm) 28 cm to 24 cm should be inside. STEP 2 : POINT WITHIN THE AREA Telescope mid way between instruments (contralateral) Manipulation angle between instruments should be 60 degrees Approximatel 7-8 cm from camera Dr Shruthi Shivdas

24. Angles in contralateral positioning Dr Shruthi Shivdas

25. Dr Shruthi Shivdas CAMERA TARGET Working Port Working Port 18 cm 24 cm BASEBALL DIAMOND 60

26. Advantages of contralateral port positioning : No magnification errors (instrument closer to camera appears larger) No movement errors ( mvt of instrument close amplified) Disadvantages Surgeon has to bend Ergonomically poor Surgeon’s hands clash with camera Dr Shruthi Shivdas

27. IPSILATERAL PORT POSITIONING 18- 20 cm 6-8cm Both can be used in ipsilateral port placement to decide position of secondary working ports (on surgeon side) and assistant ports, with respect to camera. Sectorisation used while doing omentectomy and PALND (trans and extraperitoneal). Camera in RIF; surgeon between pt legs and works on suprapubic and LIF ports. Sectoring of instruments should be avoided by beginners since it requires a greater degree of understanding of laparoscopic views and significantly different one-eye coordination; image and mobility parallax errors. Dr Shruthi Shivdas

28. FOOT end A W W Dr Shruthi Shivdas Red marks denotes adaptations for transperitoneal PALND

29. eppalnd Trocar placements for transperitoneal paraaortic lymphadenectomy. Trocar placement for extraperitoneal para-aortic lymphadenectomy. The initial entry is placed at the umbilicus to evaluate the abdominal cavity. 10-mm camera trocar 2-3 cm medial to the left ASIS surgeon uses his/her index finger to open the extraperitoneal space between the peritoneum and muscles of the abdominal wall. A balloon-tipped trocar is then inserted and used to visualize the extraperitoneal space. Insufflate the extraperitoneal space while exsufflating the peritoneal cavity at the same time. Working ports 1 – 1.5 cm medial to ant axillary line Assistant port 3 – 5 cm above camera port. C W W Dr Shruthi Shivdas

30. Leg end ASIS Subcostal Ant Ax Line CamP AssP 1 – 1.5 cm Dr Shruthi Shivdas

31. EPPALND As the camera trocar site is usually positioned more medial than the working trocars, the camera must be angled up to view the operative field. In this position, the camera driver must hold the laparoscope and camera rather low. Allowing the camera driver to sit on a stool optimizes comfort and performance. Dr Shruthi Shivdas

32. EPPALND Trocars position in the left side to access extraperitoneal space (in blue 10-mm trocars, in green 5-mm trocars, and red one for transperitoneal access). The peritoneum is dissected from theLEft psoas muscle . The left ureter is identified on the anterior surface of the psoas and is separated with the peritoneum, being the roof of the dissection plane. Nodal dissection starts at the aortic bifurcation and ends with the level of the renal veins (it is identified directly or by following the left gonadal vein). The peritoneal sac is elevated, allowing the identification of the sacral promontory and the bifurcation of the aorta and the inferior vena cava. The right common iliac vein and the right common iliac artery are dissected by gentle manoeuvres. The right ureter is identified and then elevated; next it is separated from the iliac vessels and right psoas muscle. Cranial dissection should continue with lymph dissection above the inferior vena cava. Finally, lymph nodes are carefully removed by an Endobag through the 10-mm port. Haemostasis should be evaluated. Then, the extraperitoneal space is deflated and the abdominal cavity is insufflated , a 2-cm incision is made in the peritoneal sac in order to avoid lymphocyst formation. Dr Shruthi Shivdas

33. EPPALND ADVANTAGES : faster access to the lymph nodes area with an adequate exposure of the surgical field. Trendelenburg position is not necessary, thus reducing the patient’s haemodynamic instability during surgery. the risk of postoperative complication, including ileus and intestinal obstruction, is significantly reduced. Avoid boewl adhesions and RT morbidity Maintaining the integrity of the peritoneum is a key factor during the extraperitoneal para-aortic lymphadenectomy. DISADVANTAGES the peritoneum could be damaged and opened, losing the surgical field exposure advantage provided by the pneumoperitoneum. Possible solutions to this inconvenience include occluding the foramen with a Foley catheter balloon, or performing a closure with a running suture by using a transperitoneal approach. In some circumstances the hole is impossible to close and the procedure needs to be converted to a transperitoneal route or directly to laparotomy. lymphocele formation. Leblanc showed that postoperative lymphocele was present 13.4%. After doing a preventive marsupialisation of the left paracolic gutter, however, only 3.8% developed the complication Dr Shruthi Shivdas

34. T LIFT Elevation of the peritoneum to form a tent in the case of an obscure surgical fi el Dr Shruthi Shivdas

35. SAFE entry Dr Shruthi Shivdas

36. Closed Technique- Verres Open Technique- Hassans – Primary Trocar Direct Entry with Primary Trocar Dr Shruthi Shivdas

37. Veress entry Dr Shruthi Shivdas Based on the Cochrane Review (2015), closed entry associated with the risk of failed abdominal entry (8.5–11.6%) extra-peritoneal insufflation (2%) omental injury (2%) UMBILICAL VERESS: The skin incision should be at the deepest point of the umbilical pit as this is the point where all the abdominal wall layers (skin, fascia and parietal peritoneum) merge and fuse, and there is an absence of muscles and subcutaneous fat. This is the thinnest entry point to the abdomen independent of patient’s BMI . The base of the umbilicus or trans-umbilical insertion is contraindicated in patients with known or suspected umbilical pathology (e.g., adhesions, herniation) or after three failed attempts to insert the Veress needle

38. PALMER’s POINT Dr Shruthi Shivdas Left upper quadrant (LUQ), also referred as Palmer’s point, is located 3 cm below the left subcostal border in the mid-clavicular line . (2 – 3 finger widhth lateral to midline, and 3 finger breadth below subcostal line) Nearly zero risk of injury to large vessels patients with longitudinal peri/infra-umbilical laparotomy scars, obesity very thin women with android pelvis and prominent sacral promontory in whom large vessels lie within 2 cm of the umbilicus when prominent aortic pulsations are palpated in close proximity to the umbilicus. after three failed trans-umbilical attempts. The Palmer’s point serves for both Veress needle and primary trocar insertion after abdominal insufflation . Gastric decompression is recommended Contraindications for this approach include splenomegaly, hepatomegaly, portal hypertension, gastric or pancreatic masses, history of a splenic or gastric surgery and presence or suspicion of left upper quadrant adhesions

39. “Jain Point” the Jain point” is located 10–13 cm lateral in the left para-umbilical position. Discovered by Dr Nutan Jain of Vardhaman Laparoscopy and Training Centre This non-umbilical entry site also gives an additional benefit of avoiding bowel and omental adhesions at blind umbilical entry. Aslo avoid the great vessel bifurcation at midline Dr Shruthi Shivdas

40. Dr Shruthi Shivdas Two clicks SHOULD BE be heard/ felt (resistance), corresponding to the penetration of the abdominal fascia and parietal peritoneum, respectively. . The insertion should be ceased as soon as the abdominal entry is achieved. Lateral movements of the introduced needle must be avoided, since these may enlarge a puncture visceral/vascular injury of 1.6 mm to an injury of up to 1 or more cm Spring loaded  Blunt tip retractable into sharp sheath Veress Intraperitoneal Pressure (VIP <= 10mm Hg) is the only one reliable indicator of correct Veress needle placement.

41. needle angulation Dr Shruthi Shivdas Abd wall elevation always not needed

42. separating rather than cutting  Disposable or reusable  Diameter 2mm and length 12-15mm  Insufflation upto 2.5L/min Test to identify correct position Double click test-First needle hold perpendicularly(90⁰)- resistance followed by a give felt(1st click), as passes through sheath then at 45°- click is felt as passes through peritoneum. Hanging drop method-a small amount of sterile saline is placed on the top of veress needle. The saline drops in the peritoneal cavity shows negative intraperitoneal pressure. Aspiration test-A 10ml syringe with NS is attached to the veress needle. Aspiration is done to rule out blood or bowel contents. The saline is then pushed down and aspiration is again done. If the needle placement is correct ,the fluid cannot be withdrawn as it goes it he peritoneal cavity. Veress Intraperitoneal Pressure (VIP <= 8 mmHg ; <10mm in obese) is the only one reliable indicator of correct Veress needle placement. Other Veress placement tests are not necessary while swinging needle test must be avoided COCHRANE Dr Shruthi Shivdas

43. DIRECT entry –primary trocar a single blind step without prior pneumo-peritoneum as an alternative to the Veress needle technique. After skin incision, the anterior abdominal wall is elevated by two towel clips or manually, Primary trocar should be inserted in the same direction as the Veress needle, in a controlled, two-handed manner, perpendicular till rectus sheath; angulated at peritoneum . The advantage of this method was thought to be avoidance of the complications related to Veress needle use, including extra-peritoneal insufflation, omental/intestinal insufflation and CO2 embolism as well as failed pneumo-peritoneum . Fastest entry The recommended trocars for direct peritoneal entry are to be sharp and pointed to minimize penetration force . The use of both bladeless and bladed optical trocars have been also reported , although the manufacturers generally recommend the insertion of bladed optical trocars only after pneumo-peritoneum is established. Dr Shruthi Shivdas

44. PRIMARY trocars Dr Shruthi Shivdas

45. Open entry ( hassan’s Dr Shruthi Shivdas preferred method for patients with a history of previous surgeries (i.e., suspected intra-abdominal adhesions) or after other entry techniques fail . The open technique has also been used in pregnant women, as well as in very thin patients and children who have short anterior– posterior abdominal diameters. The open (Hasson) technique is associated with a reduced rate of failed abdominal entry, without a significant difference in visceral or vascular injury rates  Blunt trocar is introduced, only after visualising omentum or bowel. Currently, blunt-tip trocars with an inflatable balloon are frequently engaged to ensure airtight fixation ( Hassons canula)

46. Radially expanding access system 1.9 mm Veress needle and an expansible external polymeric sleeve surrounding the needle. This system was developed to eliminate the use of sharp trocars, to avoid radial force and the need of fascial defect suturing, as well as to promote cannula stability. Following Veress needle insertion and abdominal cavity insufflation, the nner Veress needle is removed and the outer sleeve, that remains in the Veress needle tract, is dilated up to 12 mm by insertion of a blunt obturator trocar by twisting and pushing movements  Not found to be any safer Dr Shruthi Shivdas

47. O ptical trocar and cannula access (direct vision) technique the peritoneal cavity is approached under direct monitor view, with the following three specialized optical devises and methods: the reusable optical Veress needle, the single use optical trocar and cannula, and the reusable threaded visual cannula The single-use optical trocar, with a laparoscope in the hollowed trocar, is placed into the skin incision (0.5–1cm), perpendicular to the abdominal wall. Gentle linear pressure is applied while observing the progression of the device tip through each layer of the abdominal wall. After the abdominal cavity is reached, the hollowed trocar with the laparoscope is withdrawn, then the laparoscope reinserted through the cannula . The optical trocar (direct vision) entry is not superior to the conventional open ( Veress needle) or closed (Hasson) entry techniques regarding the risk of iatrogenic injuries (II-2/B). Dr Shruthi Shivdas

48. Optical trocar Dr Shruthi Shivdas

49. Optical threaded canula Threaded canulas eliminate the use of sharp instruments, convert the uncontrolled excessive linear entry force to a rotational radial penetration force (torque) and allow a visual entry, as a 0 laparoscope is sheathed into the hollow threaded cannula in lieu of a trocar. Threaded ports also allow successive anterior abdominal wall tissue layers to be tented upwards along the cannula’s outer threads, using Archimedes’ principle, to lift and transpose successive anterior abdominal wall tissue layers onto the cannula’s outer thread until the cannula enters the peritoneal cavity safely, under visual control. Based on available evidence, published data, expert opinion and FDA assertion, the threaded visual cannula entry system appears to be a safe entry method and instrument Dr Shruthi Shivdas

50. Injury - proofing All equipment should be checked, correct connections confirmed and laparotomy instruments available in case of conversion. Camera should be connected and white-balanced before the primary trocar placement. Urinary catheter and/or nasogastric tube are placed before laparoscopy since a filled bladder or stomach increases the risk of iatrogenic injuries. Latter especially in cases where difficult endotracheal intubation was encountered. To avoid displacement of the ‘‘pelvic’’ bowel in a cephalad direction and reduce the risk of damage to retroperitoneal structures by misdirection of the Veress needle or the primary trocar, the patients should be horizontal at the time of laparoscopic entry. After primary trocar, Inspect the abdomen with the laparoscope. The distal tip of the trocar should be within the peritoneal cavity. The area immediately under the primary trocar deployment site is the first place to be inspected for possible Veress needle of trocar injury. There should be no evidence of trauma such as blood, gastric fluid or urine in the peritoneal cavity. I Dr Shruthi Shivdas

51. INSUFFLATOR IAP for primary trocar introduction should be 25 mmHg in healthy women with immediate IAP reduction to 12–16 mmHg after all trocars have been inserted. This achieves three things: (1) creates a tense splinting effect of the abdominal wall that does not indent when linear penetration force is applied during trocar insertion, (2) Initial high IAP creates approximately 6 cm distance between the anterior abdominal wall and the underlying intra/retroperitoneal organs/structures and (3) Reducing pressure after entry avoids compromise venous return . usual adult abdominal cavity will insufflate with approximately 3 to 5 L of CO 2  gas. During Verres insufflation Initially flow rate is 1-2 L/ mte & then increased, preferably to 3-6 L/ min. Dr Shruthi Shivdas GASES USED FOR INSUFFLATION: - Filter room air -Carbon dioxide- commonly used , has advantages of being rapidly absorbed by blood, nontoxic, cost effective and can be used with cautery. CO2 is being used because same refractive index as air, doesn’t distort the image and is non combustible. -Nitrous oxide -Helium

52. Assistant Trocars insert secondary (ancillary) trocars under direct vision, at a 90 angle (perpendicular) to the skin/abdominal wall, in a controlled, screwing manner, after Trendelenburg.  Generally 5mm 10 mm port may be used with minimizer; preferred if endobag ; or camera position change anticipated (PALND/Omentectomy)  Placing working trocars too close to each other causes rolling (instruments rubbing against each other in side the patient). Specifically, the instruments can contact the camera making ideal visualization of the surgical field challenging. To prevent the physical interaction of the camera with the working trocars, the trocars should be placed a minimum of 6 cm – 8 cm apart. Lateral Trocars should be placed at least 6cm lateral to the midline to prevent epigastric injury. A safe and useful site for secondary trocar placement is located on an imaginary line connecting the umbilicus and the anterior superior iliac crest, approximately 2 cm from the iliac crest In the morbidly obese patient, the pannus pushes the peritoneum anteriorly, thereby displacing the retroperitoneum more laterally. In this patient population, moving the trocar template laterally is usually required to optimize access and surgical performance. Dr Shruthi Shivdas

53. Avoiding injury to IEA YELLOW ISLAND Accumulation of adipose subperitoneal tissue that is at the lateral third of a line between the ASIS and the umbilicus. There are no major vessels such as the IEA present in the ‘ Yellow Island ’ . It is very easy to identify in obese women in whom the IEA is dif fi cult to locate by laparoscopic visualisation. SAFE ZONES: medially, within 1 cm either side of the midline 2) laterally, more than 8 cm from the midline IEA can also be directly visualized transperitoneally . Superficial EA can be visualized by transillumination Dr Shruthi Shivdas

54. Yellow island Dr Shruthi Shivdas

55. DOOM,pain triangles corona mortis Staples or tackers should be avoided in the “triangle of pain” and in the “triangle of doom” in laparoscopic mesh hernia repair Triangle of doom is an inverted V-shaped area bound laterally by the gonadal vessels and medially by the vas deferens in male patients, or the round ligament in female patients. The EIA, external iliac vein, deep circumflex iliac vein, genital branch of the genitofemoral nerve, and femoral nerve are involved in this area. Area of the triangle of pain involves the femoral branch of the genitofemoral nerve, lateral femoral cutaneous nerve, femoral nerve, and the anterior cutaneous branch of the femoral nerve. Even a subtle injury to the nerves located within the triangle of pain is a risk factor for intractable pain. Dr Shruthi Shivdas

56. Instruments Design of instrument handle should be according to the task to be performed, pistol‐type handle for tasks that required force and axial / precision‐type handle for tasks that require precision The pistol type handle often result in compression of the digital nerves and a neuropathy, particularly of the thumb. In addition, a pistol type handle requires radial deviation of the wrist to ensure that the instrument is in line with the axis of the lower arm. Although the axial type of handle appears to be favoured for laparoscopic suturing, this type of handle results in prolonged ulnar deviation of the wrist and abduction of the shoulders. using laparoscopic instruments requires three to five times the muscle contraction force of open instruments. Dr Shruthi Shivdas

57. Laparoscopic ENERGY sources Dr Shruthi Shivdas

58. CUTTNG - When the intracellular temperature rises rapidly to more than 100°C, cellular vaporisation with explosion occurs COAGULATION : A gradual increase in temperature of between 60°C and 95°C leads to simultaneous tissue desiccation and coagulation. FULGURATION is non-contact sparking with the coagulation output to produce a superficial layer of black coagulation over a wide oozing surface. By contrast with cutting, fulguration uses high voltage with a low duty cycle of 6%. When electrical arcs hit the tissue, they produce high temperature and carbonisation. This results in a thin layer of black coagulation that insulates deeper tissue and reduces lateral thermal spread. The high voltage of fulguration helps to overcome impedance of the intervening air between the active electrode and the tissue. Dr Shruthi Shivdas

59. Power output is displayed in watts. Generally, surgeons should use the lowest effective power setting to achieve the desired effects because higher wattage is associated with increased risk of unintended tissue burns. A power setting of between 50 W and 80 W is recommended for effective cut mode, whereas a setting of between 30 W and 50 W is recommended for effective coagulation mode. The patient’s condition can dictate the appropriate power setting: muscular patients require lower settings compared with obese or emaciated patients. Dr Shruthi Shivdas

60. A continuous sinusoidal waveform with a high current and low voltage causes a rapid rise in tissue temperature to more than 100°C, which vaporises or cuts tissue with minimal coagulation. An interrupted waveform with a low current and high voltage causes a slow increase in temperature to less than 100°C, which desiccates and coagulates tissue. These two waveforms are inaccurately known as ‘cut’ (yellow-coded) and ‘coagulation’ (blue-coded) modes, respectively. Blend waveform is a modulated cut waveform with a variable duty cycle, current and voltage. They are better referred to as ‘continuous low voltage’ and ‘interrupted high-voltage’, respectively, with the blend waveform referred to as ‘interrupted low-voltage’ Dr Shruthi Shivdas

61. BIPOLAR Mechanical compression obstructs the vessel, helps to develop a proximal thrombus and eliminates the heat sink. (heat from the area carried away by flow of blood) Mushroom (outside loop) effect As the grasped tissue desiccates and coagulates, its impedance increases, forcing the current to take a path of least impedance outside the jaws of the bipolar instrument. This can result in collateral thermal injury to nearby vital structures (Figure 4). Electrical bypass effect Overcompression of the tissue between the jaws of the bipolar instrument may cause them to touch, leading to electrical bypass and deficient tissue coagulation Dr Shruthi Shivdas

62. Traditional energy devices Monopolar energy requires that the current from the generator pass from the active electrode through the patient and out of the body through a dispersive electrode pad (grounding pad) connected to the generator to form a complete circuit. In bipolar energy ,the active electrode and the return electrode are integrated into the energy delivery instrument with the target tissue being grasped between to complete the circuit, sparing the patients body from the circuit,  making bipolar energy more precise,more haemostatic and less likely to cause collateral damage to adjacent tissues. Disadvantages of bipolar: needs increased time for coagulation due to a low power setting, which leads to charring and tissue adherence with incidental tearing of adjacent blood vessels. the electrodes cannot cut tissue. Even if a continuous (cut) waveform is applied to bipolar instruments, cutting is inefficient. Dr Shruthi Shivdas

63. Antenna coupling This phenomenon occurs when the active electrode cord (transmitting antenna) emits electromagnetic energy in the air, which is captured by a nearby inactive cord or wire (receiving antenna). It may be regarded as a type of capacitive coupling and can result in unintended tissue burns. The receiving antenna may be the camera cord or wires of monitoring devices such as electrocardiography or neuromonitoring devices Robinson et al.31 found that separating the laparoscopy tower from ESU, avoiding parallel arrangement of cords and lowering the power setting reduced antenna coupling ( Dr Shruthi Shivdas

64. Monopolar injuries  In a review of laparoscopic bowel injuries managed at Johns Hopkins, 50% of the injuries were associated with cautery burns.  There are 3 types of monopolar energy damage that can occur. Insulation failure DIRECT COUPLING CAPACITATIVE COUPLING BOTH ARE USUALLY MISSED INTRAOP; PRESENT POSTOPERATIVELY Dr Shruthi Shivdas

65. DIRECT COUPLING Direct coupling occurs when an active electrode makes an unintended contact with another non isulated metal instrument. Recognition of this complication may be delayed until the postoperative period with serious consequences To avoid a direct coupling the surgeon should not activate the generator while the active electrode is touching or in close proximity to another metal object, especially with a plastic canula WITH metal trocars, if the active electrode touches the instrument, the current will simply flow from the instrument to the metal trocar. As long as the trocar is in contact with a relatively large portion of the abdominal wall, the current will not concentrate. Instead, it will dissipate harmlessly from the trocar through the abdomen and back through adjacent tissue to the return electrode. If the trocar is completely or partially constructed of plastic (HYBRID TROCARS), however, the energy may not be able to dissipate back through the body. The metal within the trocar will build up a charge, which could eventually arc to adjacent tissue and back to the return electrode, but at a harmful level of current. In doing so, it may travel through the bowel, skin, or even the operator’s hands, causing burns. Dr Shruthi Shivdas

66. CAPACITATIVE COUPLING This occurred in the early days of laparoscopic surgery with the use of plastic fixation screws to fix metal ports to the abdominal wall so as to prevent them from being accidentally pulled out or pushed when instruments were withdrawn during the course of an operation. Whenever current is applied through an insulated instrument inserted through a metal trocar (port) some radio frequency electric charge is transferred to the metal cannula by every activation (even if the insulation of the instrument is perfect). This effect is known as capacitance coupling (THE ABILITY OF TWO METAL CONDUCTORS TO CONDUCT CURRENT BETWEEN THEM THROUGH A LAYER OF INSULATION.) There is absolutely no problem if the metal cannula is in contact with the full thickness of the abdominal wall, as the charge accumulated by the cannula is immediately discharged over a wide contact area (low power density, like the neutral return electrode plate) and hence no damage is done. However, if the cannula is isolated from the abdominal wall, by a plastic screw (acting as an insulator), the cannula can not discharge and thus accumulates a substantial charge with repeated activation of the electrosurgical instrument. Thus, in essence, it becomes an electric accumulator! Should at any stage, the tip of the cannula inside the abdomen touch tissue or bowel, the accumulated charge will discharge immediately through a single point of contact, i.e. with a high power density sufficient to cause an electrical burn. Since this occurs away from the site of action of the operation, it is usually overlooked. Dr Shruthi Shivdas

67. AEM To protect patients from stray currents that may be released through faulty insulation, the electroshield system was introduced. The electroshield system uses active electrode monitoring (AEM). The conductive shielding within the insulation itself becomes "capacitively coupled" to the active electrode, and not any metal surgical instruments or patient's tissue, eliminating the incidence of tissue burns from capacitive coupling. The conductive sheath is electrically connected to the return electrode of the electrosurgical unit, allowing for harmless dissipation of capacitively coupled currents. If stray energy levels become sufficiently high to damage non-targeted tissues, the AEM circuit interrupts the flow of energy from the electrosurgical unit and sounds an alarm. Monopolar energy should only be used in laparoscopy in conjunction with the AEM system. Dr Shruthi Shivdas

68. Good practice in electrosurgery Monopolar devices Use the lowest possible power setting. Use short intermittent activations. Allow a safety margin when close to vital structures because of lateral thermal spread. Avoid activation in close proximity to or in contact with another metal instrument. Use return electrode monitoring and active electrode monitoring technology. Bipolar devices Avoid tension on the tissue during activation because this compromises coagulation. In areas with anatomical tension, repeat coags with overlapping of the seal, without leaving any unsealed tissue in between two seals . Keep the jaws of the instrument clean at all times by wiping with a wet swab to achieve adequate tissue effects. To prevent tissue charring, activate the instrument in a short intermittent manner and release the tissue just before current flow is terminated at the vapour phase. When stuck to tissue, re-approximate the jaws and reactivate before opening them. The tissue can also be irrigated with fluid before reactivation. Avoid over-compression of grasped tissue to prevent the bypass effect do not include a big bundle of tissue in the jaws of the instrument for a good seal. Consider skeletonising vessels before application to achieve a good seal. Dr Shruthi Shivdas

69. Advanced Bipolar Energy devices/vessel sealers These devices produces a hemostatic seal by applying high current and low voltage, which differs from the energy used in standard monopolar and bipolar cautery (high voltage and low current). The system senses uses the end-effector to sense the impedance of the tissues within the jaw, and adjusts the energy accordingly. Once the impedance monitor detects that the seal is complete, a brief period of cooling ensues. After the tissue cools and is ready to be divided, the surgeon is notified by an audible tone. The bipolar energy fuses collagen fibers within the vessel wall to produce a translucent seal The delivery of electrical energy by the advanced bipolar system is highly pulsatile, allowing for tissue cooling during activation in an attempt to minimize lateral thermal spread . .All advanced bipolar devices are capable of tissue transection with an incorporated cutting mechanism . The cutting device is most commonly a retractable blade built into the jaws of the instrument Advanced bipolar devices have been approved by FDA to seal vessels up to 7 mm in diameter . Currently available advanced bipolar technologies include LigaSure (Covidien, Mansfield, MD, USA), Starion Tissue Welding system (Sunnyvale, CA, USA ), EnSeal (Ethicon Endo-Surgery, Cincinnati, OH, USA), and Plasma Kinetic System (PKS; Gyrus ACMI, South- borough, MA, USA) Dr Shruthi Shivdas

70. Advanced bipolar devices LIGASURE ADVANCE WITH MONOPLOAR TIP Dr Shruthi Shivdas ALL work by approximation of vessels walls along with fibrin formation

71. LIGASURE MARYLAND Thin curved tip Dissection capability Button for one step sealing & cutting Dr Shruthi Shivdas

72. ULTrasonic devices Work on principle of piezoelectricity (conversion of mechanical energy to electrical enery . Ultrasonic devices have piezoelectric crystals that generate mechanical vibrations at over 20 kHz (i.e., above the audible range). The high frequency vibration of tissue molecules generates stress and friction in tissue, which generates heat and causes protein denaturation. Ultrasonic energy sources result in less charring of tissue, less lateral thermal spread (0-1mm), and less particulate plume ("smoke") that can degrade the surgeon's vision. Also can be used as a dissector, in addition to coagulation and cutting. Dr Shruthi Shivdas

73. AVAILABLE INSTRUMENTS ETHICON : Initially the prototype Ultracision Harmonic Scalpel was developed for commercial use, which was approved to seal vessels up to 3 mm in diameter. The Harmonic ACE (Ethicon Endo-Surgery) was subsequently developed; with an active jaw frequency of 55 kHz, and has been approved by FDA to seal vessels up to 5 mm in diameter. Harmonic Ace +7 shears FDA approved for 7mm vessel sealing COVIDIEN:AutoSonix (Covidien), Sonocision (Covidien) SonoSurg (Olympus America, Center Valley, PA, USA). Dr Shruthi Shivdas BOTH USE ADAPTIVE TISSUE TECHNOLOGY