Methods of Myocardial Protection Myocardium need vs. Surgical demand! Surgeon wants: rapid induction, maintenance and easy reversal of cardiac arrest relaxed heart to allow for mobilization and traction a preferably bloodless and unobscured field sufficient time for adequate correction of cardiac or coronary defects Achieved by: Diastolic arrest + minimal coronary perfusion with blood +…
Intraoperative Cell Salvage (ICS) is a technique used to recover and re-infuse red blood cells during and after surgery, to reduce transfusion requirements of the patient. It removes non-cellular matter by centrifugation commonly or a counter-current system. It receives blood from: Suction – use large-bore suction tip (>4mm; e.g. Yankauer), avoid surface skimming and set vacuum…
Mechanism Roller pump at low RPM with gravity/siphoning principle Without roller-pump gravity-only circuit. Indications Reduce distension: blood leakage into heart during CPB causes distension àincreases O2 demand + impairs subendocardial perfusion Bloodless field Reduce myocardial rewarming Prevent ejection of air Usually only left heart is vented as right is vented by venous cannulae. Causes of…
Indications Maintain visibility in operative field Prevent distension of cardiac chambers Post-heparinisation suction device ‘Sucker bypass’ – if extreme haemorrhage, until venous cannulation is established Mechanism Suction driven by roller pump. The position adjusted by surgeon and flow rate adjusted by perfusionist to keep pressure as low as needed to prevent injury to blood and…
Devices Cardiotomy x 2: ‘Blue’, ‘Clear’ Cardiac Vent x 1: ‘Green’ Cell Salvage (ICS) x 1 Wall/generic suction Suction tips Plastic vs. Metal Yankauer vs Coronary/small Principles On CPB, Cardiotomy suction to catch all bleeding except: Topical cooling solution – can cause haemodilution Low visibility – use ICS, if not adequate, use wall sucker as well Debris (e.g. irrigation of…
Procedure The aortic adventitia is dissected with McIndoe’s scissors away from the proposed site of anastomosis. A side-clamp is applied to the ascending aorta, and its position fine-tuned with a Duvall clamp. A stab incision is made with a 15-blade scalpel and an aortotomy punch passed inside to make a circular hole. Any pieces of…
Procedure After haemostasis of the median sternotomy wound, apply an internal mammary retractor to elevate the left hemi-sternum. The pericardium may be left closed. Position the patient so the internal sternal edge is just above eye-level. This would mean raising the bed and rotating it away from the operator. The operator may be standing. A…
Procedure The patient is positioned sitting at 45 degrees, and hands above head to retract scapula. Scrub up (wash hands, hat, mask, gown, sterile gloves) Identify the triangle of safety: anteriorly the lateral border of pectoralis major, posteriorly the lateral border of latissimus dorsi and inferiorly the superior border of the 5th or 6th rib.…
Procedure The landmark and ultrasound-guided techniques may be used to cannulate usually the right IJV. The patient is supine in a Trendelenburg position (head down) to distend the right IJV. With the head turned to the left, the IJV may be identified superiorly in the carotid triangle anterior to the anterior border of sternocleidomastoid muscle,…
Instruments Positioning – bandage roll, tape Local anaesthesia – 5ml syringe, lidocaine 1%, alcohol wipe Aseptic technique – mask, sterile gloves, hat, gown, chlorhexidine prepping sponges x3, fenestrated drape, sterile swabs Arterial cannula – with needle+cannula or needle+guide-wire, (2ml syringe) Heparinised saline – 10-20 mls, in a syringe. Security – silk suture+straight needle, scissors, adhesive…