Downloaded 25 times
More Related Content
![PERI-PROSTHETIC FRACTURE NAIL-PLATE CONSTRUCT [NPC].pptx](https://cdn.slidesharecdn.com/ss_thumbnails/drarunkumardrmohamedashrafperiprostheticfrasturenail-plateconstructnpc-260209164459-7e9d15a1-thumbnail.jpg?width=640&height=640&fit=bounds)
Cannulation .pptx
- 1.
- 2. CANNULATION The establishment and maintenanceof adequate vascular access is essential for CPB or ECMO
- 3. Introduction ■ Primary functionof CPB is to divert blood from heart and lungs. ■ Blood is drained by gravity siphonage through svc/ivc/RA ■ To return the blood to the systemic arterial system. ■ Blood returned through aortic cannula placed in the ascending aorta. ■ Peripheral cannulation using femoral or other means used when central cannulation is not possible.
- 6. Venous cannulation ■ Principle 1)Gravity siphonage 2) Vacuum assisted venous drainage.
- 7. Gravity drain ■ Twoconstraints 1) Venous reservoir – below the level of patient 2) The lines must be filled with blood or fluid.
- 8. Gravity drain contd., Theamount of venous drainage is determined by 1) Pressure in central vein(Pt. blood volume) 2)The height difference b/w pt. ` and top of blood level in venous reservoir. 3) Resistance in venous cannulas
- 9. Venous drainage ■ Venousdrainage is affected by 1) Intravascular volume and venous compliance. 2) Sympathetic tone 3) Venous chattering/fluttering
- 10. Venous cannula ■ Bicaval ■Single atrial ■ Cavo atrial ■ Proper positioning is critical
- 11. Other approaches ■ Femoral/iliac ■ Open/percutaneous ■ Indications -Emergency purpose ■ Special cannulas- long, ultrathin & wire reinforced
- 12. Types and sizeof venous cannulas ■ Mainly two types 1) Single stage 2) Two stage(Cavoatrial). ■ Made of flexible plastic ■ Wire reinforced(prevents kinking) ■ Straight or right angled. ■ Tips made of thin plastic or metal(for better id/od ratio) ■ 1/3rd of total flow – svc and 2/3rd –ivc ■ Not meant for reuse but cost constraints have led to resuse.
- 13. Connection to thepatient ■ Accomplished by inserting cannula into RA ■ Three basic approaches 1) Bicaval 2) Single Atrial 3) Cavo arterial(two stage approach)
- 14. Comparison of venouscannulation methods Bicaval With tourniquet Without tourniquet single Atrial cavoatrial Atrial incisions 2 2 1 1 Speed of cannulation Slowest Slow Fast Fast Technical difficulty Most difficult Difficult Easy Moderately easy Rt. Heart exclusion Complete Incomplete No no
- 15. Comparison of venouscannulation methods Bicaval With tourniqu et Without tourniquet single Atrial cavoatrial Coronary sinus return Excluded Partial Included included Rt.heart decompression None Fair Good best Right. Heart decompression with heart lifted up Bad Bad Bad good
- 16. Bicaval single With tourniq uet without Atrialcavoatrial Caval drianage Best About as good Not as good for ivc Not as good for svc Caval drainagewith heart lifted up Good Good Bad Ivc adeauate svc bad Adequate venous drinage forall types of surgery Yes Yes No no
- 17. Bicaval single With tourniq uet without Atrialcavoatrial Potential rewarming of heart by systemic venous return No yes yes yes myocardial preservation Best Good Suboptimal Controver sial
- 18.
- 19. Two stage VsBicaval
- 20. Persistent LSVC ■ LSVCpresent in .3% to .5% of population ■ LSVC usually drains into coronary sinus and than into the RA. ■ In some cases, LSVC drains into LA ■ LSVC should be suspected when large coronary sinus is noted on echo. ■ Suspect LSCV when Rsvc small ■ Left innominate vein small or absent
- 21. Solution ■ Use cardiotomysuction in the coronary sinus ■ Cannulate LSVC
- 22. Augmented venous drainage ■To reduce circuit volume ■ Three methods: 1) Roller pump 2) Kinetic pump 3) VAVD
- 23. Precautions ■ Regulation ofnegative pressure ■ Not to exceed – 60 to – 100 mmhg ■ 20 mmhg is enough ■ Vacuum applied after initiation of CPB
- 24. Complications of augmentedreturn ■ Hemolysis due to excessive – ve pressure. ■ Collapse of venous structures possible ■ Aspiration of macro and micro air ■ Presence of PFO can cause air embolism.
- 25. Complication associated with venousdrainage ■ Atrial arrhythmias ■ Bleeding of the atrium ■ Air embolization (low arterial pressure could cause systemic embolization with potential right to left shunts) ■ Malposition of tips(inserting the tip into azygos,innominate or hepatic veins or across an ASD into left heart) ■ Caval tapes may occlude venous lines
- 26. Causes of lowvenous return ■ Inadequate height ■ Malposition of venous cannulas ■ Obstruction or excess resistance ■ Inadequate venous pressure(venodilation or hypovolemia) ■ Kinks, airlocks During rewarming tendency for kinking is more(softening of tubes) ■ Surgical manuplation.
- 27. Causes of lowvenous return contd., ■ Low venous pressure ■ Hypovolemia ■ Drug induced venous dilation ■ Small cannula ■ Excessive flow resistance ■ Partial obstruction causes of venous return causes RV distension and contractility impairment
- 28. Arterial cannulation ■ Sites 1.Proximal aorta 2. Innominate artery 3. Distal aortic arch 4. Femoral 5. External illiac 6. Subclavian and axillary artery
- 29. Choice of cannula ■Influenced by 1. The planned operation 2. The distribution of atherosclerotic disease
- 30. Arterial cannulation ■ Cannulas Availablein different types 1) Rt angled tips 2) Tapered 3) Flanges ■ Narrowest part of ECC.
- 31. Hemodynamic charecteristics ■ Pressuredrop ■ Performance index(pressure gradient versus OD at any given flow) ■ The use of thin metal or hard plastic for the tip provides the best id/od ratio ■ Pressure gradients exceeding 100 mmhg are associated with excessive hemolysis and protein denaturation ■ Jetting effect produced by small cannulas may damage the ineterior aortic wall,dislodge atheroemboli(sandblasting) and cause dissection
- 32. Connection to thepatient ■ Ascending Aorta ■ Femoral artery ■ Abdominal aorta ■ Auxillary artery ■ Left common carotid artery(LCCA) ■ LV apex
- 35. Ascending Aorta ■ Advantagesease,safe and no additional inscision. ■ Optimal BP during cannulation – 70 to 80 mmhg(mean) systolic – 100 ■ If pressure too high – greater chance of tear and dissection ■ If pressure too low - Aorta tend to collapse, difficult to make inscision and greater risk of tear
- 36.
- 37. Ascending aorta contd., ■After cannulation confirm intraluminal placement by noting pulsatile flow in the systemic line pressure. ■ CPB line pressure approx = radial artery ■ Proper position of cannula tip is important(1 to 2 cms into aorta) ■ Directed towards middle of tranverse arch
- 39. Potential complications ■ Atherosclerosiswith or without calcification ■ Atherosclerosis is a risk factor for perioperative aortic dissection and post op renal dysfunction ■ Inabillity to introduce cannula ■ Intramural placement ■ Dislodgement of atheroemboli ■ Air embolism from the cannula
- 40. Complication contd., ■ Persistentbleeding around the cannula. ■ Malposition of the tip to retrograde position or even across the aortic valve. ■ malposition against vessel wall or into the aortic arch vessels ■ Obstruction of aorta infants ■ Aortic dissection and high cpb line pressure
- 41. Complications summary ■ Difficultinsertion ■ Bleeding ■ Tear in the aortic wall ■ Malposition of cannula tip ■ Atheromatous emboli ■ Failure to remove all air from arterial line ■ Injury to aortic back wall
- 42. Contd., ■ Inadequate orexcessive cerebral blood flow ■ Inadvertent decannulation ■ Aortic disection
- 43. Points to beobserved during aortic cannulation ■ High systemic line pressure ■ High pressure in radial artery ■ Asymmetric coolling of the neck ■ Facial edema,dilated pupils ■ Before cpb radial artery catheter may reveal sudden damping ■ Sand blasting effect
- 44.
- 45. Femoral artery ■ Indications 1)Aneurysm in ascending aorta 2) no space avilable 3) Severe calcification 4) Re-do surgeries
- 48. Femoral artery complications ■Trauma to cannulated vessel ■ Late stenosis ■ Infection ■ Embollization ■ Limb ischemia ■ retrograde arterial dissection
- 49. Abdominal aorta ■ cannulatingthe abdominal aorta through a graft is reported.
- 50. Auxillary artery cannulation ■Performed either directly or through an attached 8mm graft. ■ Advantages 1. Less likely to have atheroscleorosis 2. Has good collateral flow 3. Decreases the risk of ischemic complications 4. Healing is better and wound complications are less
- 51. Advantages of auxillaryartery cannulation contd., ■ Its antegrade flow also reduces the chances of cerebral atheroembolization ■ Used for establishing deep hypothermia before repair of type A aortic dissection ■ Rt.auxillary artery is more favoured.
- 52. Complications of auxillaryartery cannulation. ■ Auxillary artery injury,thrombosis ■ Ischemia or compartmental syndrome in the arm ■ Poor perfusion due to high resistance due to small artery or local dissection
- 53.
- 55. Innominate artery ■ Eliminatesthe need of second incision ■ 7 to 8 mm cannula directed towards the aortic arch
- 56. Left common carotidartery(LCCA) ■ Approach through extrathoracic incision in the neck and 8 mm graft sutured end to side and 22fr cannula inserted ■ Used for selective perfusion of the brain at 10 to 15 ml/kg/min at 15 degrees centrigrade. ■ Perfusion pressure < 80 mmhg(Needle placed in common caroted artery)
- 57. Left ventricular apex ■Cannulating the LV apex and passing the cannula across the aortic valve in the aortic root is reported.
- 58. Arterial cannulation Ascending aortaor arch Easy Femoral or iliac Accessibility More difficult Additional incision Cannula size Obstruct ascending aorta Risk of malperfusion of arch vessels No yes Usually unlimited Possible limited no Yes no Perfusion direction Leg ishcemia Antegrade retrograde No possible
- 59. Ascending aorta orarch Femoral or illiac Aortic dissection incidence .01 to .09% .2 to 1% Leg wound and artery complications 0 4% Indications Most cases When aortic cannulation not feasible Contra indications Ascending aortic aneurysms, diseased ascending aorta When aortic cannulation feasible,occlusive disease of vessels