Sternal Retractor

Abstract

Devices and methods for sternal retraction that reduces bleeding from the cut edges of a sternum and reduces fracturing of the sternum during retraction. The devices and methods involve the use of sternal refractor blades having a certain geometry and inserts placed inside the sternal retractor blades during retraction of the sternotomy incision. The blades and inserts act to tamponade the blood flow from the cut sternal edge and reduce fracturing of the sternum during retraction.

What is claimed is: 
     
         1 . A retractor blade for use with a sternal retractor having one fixed arm and a second movable arm, wherein the blade comprises:
 a rigid frame configured to attach to a retractor arm; and   an insert configured to fit inside the rigid frame;   wherein the rigid frame is substantially the length of a cut sternal edge; and   wherein the insert is configured to reduce bleeding from a cut sternal edge.   
     
     
         2 . The retractor blade of  claim 1 , wherein the length of the rigid frame is at least 50% the length of the cut sternal edge. 
     
     
         3 . The retractor blade of  claim 1 , wherein the length of the rigid frame is at least 75% the length of the cut sternal edge. 
     
     
         4 . The retractor blade of  claim 1 , wherein the length of the insert is at least 50% the length of the cut sternal edge. 
     
     
         5 . The retractor blade of  claim 1 , wherein the length of the insert is at least 75% the length of the cut sternal edge. 
     
     
         6 . The retractor blade of  claim 1 , wherein the frame has a floor, two side walls, and a closed or notched cephalad end and the frame is configured to encase the cut sternal edge. 
     
     
         7 . The retractor blade of  claim 1 , wherein the length of the frame is from about 7 cm to 25 cm and the width is between about 1.0 and 3.5 cm. 
     
     
         8 . The retractor blade of  claim 1 , wherein the frame is bent and has a caudal section about 4 to 20 cm in length and a cephalad section about 3 to 5 cm in length. 
     
     
         9 . The retractor blade of  claim 4 , wherein the angle of curvature between the caudal section and the cephalad section is from about 5 to 30 degrees. 
     
     
         10 . The retractor blade of  claim 1 , wherein the insert attaches to the frame with a friction fit, snaps onto the frame, attaches with Velcro®, or attaches with adhesive. 
     
     
         11 . The retractor blade of  claim 1 , wherein the frame has an inwardly directed lip and the insert is slid into the frame under the lip from the open caudal end of the frame. 
     
     
         12 . The retractor blade of  claim 1 , wherein the insert material is irreversibly molded onto the frame of the blade. 
     
     
         13 . The retractor blade of  claim 1 , wherein the insert is conformable to the cut sternal edge. 
     
     
         14 . The retractor blade of  claim 1 , wherein the insert is made from a silicone or thermoplastic elastomer. 
     
     
         15 . The retractor blade of  claim 1 , wherein the insert comprises a material that conforms to the cut sternal edge, has a durometer ranging from 10 to 50 Shore A, and is biocompatible and sterilizable. 
     
     
         16 . A sternal retractor comprising a first fixed arm and a second movable arm and a rack and pinion mechanism to move the first and second arms away from each other and further comprising a blade of  claim 1  attached to each arm, wherein the blades pivot on the retractor arms from 0 to 45 degrees away from the centerline of the retractor. 
     
     
         17 . The retractor of  claim 16 , wherein the blades pivot on the retractor arms from 15 to 30 degrees away from the centerline of the retractor. 
     
     
         18 . The retractor of  claim 16 , wherein the means of attaching the blades to the retractor arms is reversible, such that the rack and pinion may be positioned either cephalad or caudad. 
     
     
         19 . A retractor blade for use with a sternal retractor having a first fixed arm and a second movable arm, wherein the blade comprises:
 a rigid frame configured to attach to a refractor arm; and   wherein the rigid frame is substantially the length of a cut sternal edge.   
     
     
         20 . The retractor blade of  claim 19 , wherein the length of the rigid frame is at least 50% the length of the cut sternal edge. 
     
     
         21 . The retractor blade of  claim 19 , wherein the length of the rigid frame is at least 75% the length of the cut sternal edge. 
     
     
         22 . The retractor blade of  claim 19 , wherein the frame has a floor, two side walls, and a closed or notched cephalad end and the frame is configured to encase the cut sternal edge. 
     
     
         23 . The retractor blade of  claim 19 , wherein the length of the frame is from about 7 cm to 25 cm and the width is between about 1.0 and 3.5 cm. 
     
     
         24 . The retractor blade of  claim 19 , wherein the frame is bent and has a caudal section about 4 to 20 cm in length and a cephalad section about 3 to 5 cm in length. 
     
     
         25 . The retractor blade of  claim 24 , wherein the angle of curvature between the caudal section and the cephalad section is from about 5 to 30 degrees. 
     
     
         26 . The retractor blade of  claim 24 , wherein the width of the frame tapers over the length of the frame, with the cephalad end being wider and the caudal end being narrower. 
     
     
         27 . An insert for use with a sternal retractor that has two opposed blades that are placed onto the cut edges of a sternum and moved away from each other in order to spread apart the cut edges of a sternum, wherein the insert is configured to mount onto the surface of a blade that engages the cut sternal edge and wherein the insert extends substantially the length of the cut sternal edge and reduces blood flow from the cut sternal edge. 
     
     
         28 . The insert of  claim 27 , wherein the length of the insert is at least 50% the length of the cut sternal edge. 
     
     
         29 . The insert of  claim 27 , wherein the length of the insert is at least 75% the length of the cut sternal edge. 
     
     
         30 . The insert of  claim 27 , wherein the insert is conformable to the cut sternal edge. 
     
     
         31 . The insert of  claim 27 , wherein the insert is made from a silicone or thermoplastic elastomer 
     
     
         32 . The insert of  claim 27 , wherein the insert comprises a material that conforms to the cut sternal edge, has a durometer ranging from 10 to 50 Shore A, and is biocompatible and sterilizable. 
     
     
         33 . The insert of  claim 32 , wherein the durometer of the insert ranges from 20 to 40 Shore A. 
     
     
         34 . The insert of  claim 27 , wherein the insert contains one or more active agents selected from pro-thrombic agents, antimicrobial agents, analgesic agents, and osteoblastic agents. 
     
     
         35 . A method for performing a surgical procedure involving a sternotomy with less bleeding from the cut sternal edge comprising using a sternal retractor having blades that extend at least 50% the length of the cut sternal edge. 
     
     
         36 . The method of  claim 32  wherein the blades further include an insert that conforms to the cut sternal edge. 
     
     
         37 . A method of performing a surgical procedure involving a sternotomy with lower incidence of sternal breakage comprising using a sternal retractor having blades that extend at least 50% the length of the cut sternal edge. 
     
     
         38 . The method of  claim 37  wherein the method further involves using a retractor with pivoting blades or pivoting arms so that the sternum is opened more widely at its caudal end than at its cephalad end.