Name:
06 Median Sternotomy Heart
Description:
06 Median Sternotomy Heart
Thumbnail URL:
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Duration:
T00H05M28S
Embed URL:
https://stream.cadmore.media/player/21602dfd-a00e-4500-977b-4cab31e788fe
Content URL:
https://cadmoreoriginalmedia.blob.core.windows.net/21602dfd-a00e-4500-977b-4cab31e788fe/0620Median20Sternotomy20Heart.mov?sv=2019-02-02&sr=c&sig=sTYWu9z7IFawiWFzUSuHvH8qr49K3awwyGINDquiWC4%3D&st=2024-05-02T22%3A53%3A06Z&se=2024-05-03T00%3A58%3A06Z&sp=r
Upload Date:
2022-03-03T00:00:00.0000000
Transcript:
Language: EN.
Segment:0 .
In this video, we will discuss the proper technique to perform median sternotomy for exposure of the heart and repair of cardiac injuries.
Segment:1 Objectives.
We will begin by reviewing the anatomy, the necessary instruments, proper patient positioning, and then demonstrate exposure of the heart through a median sternotomy and repair of cardiac injuries. Finally, we will discuss the tips and pitfalls of this exposure.
Segment:2 Anatomy.
The heart lies directly posterior to the sternum, and therefore a median sternotomy provides optimal exposure for cardiac injuries, most of which are due to penetrating trauma.
Patients presenting without vital signs, however, should be managed instead with an emergency room thoracotomy and possible clamshell thoracotomy to enable cardiac massage across clamping of the descending aorta. The heart is enveloped by the pericardium, which also contains the root of the ascending aorta, pulmonary artery and veins, and the last two to four centimeters of the superior vena cava and inferior vena cava.
The phrenic nerves descend along the lateral surfaces of the pericardium. As little as 200 cc of blood in the thick fibrous pericardium can result in cardiac temponade, so prompt recognition of cardiac injury is imperative. The right ventricle is the most anterior chamber of the heart. It is therefore the most commonly injured. The left ventricle lies laterally at the apex, and is much thicker walled. The left anterior descending artery lies in the groove between the right and left ventricles.
And the right coronary artery lies in the groove between the right ventricle and right atrium.
Segment:3 Instrumentation and Positioning.
The patient should be positioned supine with arms abducted out at 90 degrees. The patient should be prepped and draped from the neck to the knees to allow for extension of the incision, as well as for possible saphenous vein harvest as necessary. Instruments should include a sternotomy tray, sternal saw or lebsche knife, Finochietto or Canadian sternal retractor, vascular instruments, and vascular conduits.
The skin incision is made from the sternal notch to below the xiphoid process. The incision is carried down to the fascia to the sternum, and the sternum is scored with electrocautery. The interclavicular ligament at the sternal notch is divided with electrocautery, so as to allow purchase for the sternal saw. Pass a finger under the sternum from above and below to allow for safe passage of the sternal saw.
Ventilations are temporarily suspended. The hook of the sternal saw is engaged at the suprasternal notch and upward traction is maintained as the sternum is divided in the midline. The sternum is then gently spread manually and the Finochietto retractor is placed at the upper part of the sternum with the opening facing superiorly. The pericardium is then visible and divided in the midline and teed off at the base. On inspection of the heart, note the location of the left anterior descending artery, the left ventricle, right ventricle, and right coronary artery.
The left atrial appendage is found posteriorly on the left. And the right atrial appendage is seen posteriorly on the right. After repairing cardiotomy, control bleeding
Segment:4 Cardiac Repair.
with direct finger compression. In the emergency room, temporary control may be obtained by placing a Foley catheter into the injury and inflating the catheter. The cardiac wound is repaired with figure of eight or horizontal mattress sutures, using a 2-0 or 3-0 non-absorbable monofilament suture on a large tapered needle.
PLEDGES: may be reserved for cases where the myocardium tears during tying of the sutures. Injuries near a coronary artery should be repaired with horizontal mattress sutures under the artery so as to not ligate it and preserve distal perfusion to the myocardia. Elevating the heart out of the chest will kink the inflow to the heart, which will result in cardiac arrest and is not advised. In order to expose posterior injuries to the heart, it is better to sequentially place laparotomy pads behind the heart, or to grasp the apex of the heart with a Duval clamp and gently retract inferiorly and slowly elevate the heart.
Segment:5 Tips and Pitfalls.
PLEDGES: Median sternotomy provides excellent exposure of the heart, however patients without vital signs should undergo resuscitative thoracotomy. Failure to divide the interclavicular ligament will cause the pneumatic sternal saw to seize, as it does not work on soft tissues. In patients with a tense pericardium, it is difficult to grasp, so use a scalpel to facilitate injury. Always inspect the internal mammary arteries for injury prior to closure of the sternotomy.
PLEDGES: Injuries near coronary arteries should be repaired with horizontal mattress sutures under the vessel. Elevation of the heart out of the chest is not well-tolerated. Place laparotomy pads under it sequentially, or grasp the apex with a Duval clamp to expose the posterior surface. Place epicardial pacing leads after cardiac repair in case of postoperative arrhythmia. Postoperatively, all patients should undergo early routine echocardiography to rule out intracardiac injuries such as septal defects, valvular or papillary muscle dysfunction.
PLEDGES: Wall motion abnormality is indicative of ischemia and pericadial effusion. Thank you.