A system for treating a tissue site, comprising: a dressing assembly, comprising: a dressing bolster having a first side and a second side, a comfort layer coupled to the second side of the dressing bolster, a sealing member comprising: a first sealing member (132, 226) covering the first side of the dressing bolster, and a second sealing member (134, 228) covering a portion of the second side of the dressing bolster and extending outward from the dressing bolster, wherein a portion of the first sealing member (132, 226) is coupled to the second sealing member (134, 228), and a sealing ring (117, 248) positioned at the second side of the dressing bolster, wherein the first sealing member (132, 226), the second sealing member (134, 228), and the sealing ring (117, 248) are configured to provide a sealed space at the tissue site; an access portal coupled to an exterior surface of the sealing member, wherein the access portal is configurable between an open state and a closed state, wherein the access portal provides a passage into the sealed space in the open state and a fluid seal in the closed state; and a reduced-pressure subsystem comprising a reduced-pressure source configured to be coupled in fluid communication with the sealed space. a dressing assembly, comprising: a dressing bolster having a first side and a second side, a comfort layer coupled to the second side of the dressing bolster, a sealing member comprising: a first sealing member (132, 226) covering the first side of the dressing bolster, and a second sealing member (134, 228) covering a portion of the second side of the dressing bolster and extending outward from the dressing bolster, wherein a portion of the first sealing member (132, 226) is coupled to the second sealing member (134, 228), and a sealing ring (117, 248) positioned at the second side of the dressing bolster, wherein the first sealing member (132, 226), the second sealing member (134, 228), and the sealing ring (117, 248) are configured to provide a sealed space at the tissue site; a dressing bolster having a first side and a second side, a comfort layer coupled to the second side of the dressing bolster, a sealing member comprising: a first sealing member (132, 226) covering the first side of the dressing bolster, and a second sealing member (134, 228) covering a portion of the second side of the dressing bolster and extending outward from the dressing bolster, wherein a portion of the first sealing member (132, 226) is coupled to the second sealing member (134, 228), and a first sealing member (132, 226) covering the first side of the dressing bolster, and a second sealing member (134, 228) covering a portion of the second side of the dressing bolster and extending outward from the dressing bolster, wherein a portion of the first sealing member (132, 226) is coupled to the second sealing member (134, 228), and a sealing ring (117, 248) positioned at the second side of the dressing bolster, wherein the first sealing member (132, 226), the second sealing member (134, 228), and the sealing ring (117, 248) are configured to provide a sealed space at the tissue site; an access portal coupled to an exterior surface of the sealing member, wherein the access portal is configurable between an open state and a closed state, wherein the access portal provides a passage into the sealed space in the open state and a fluid seal in the closed state; and a reduced-pressure subsystem comprising a reduced-pressure source configured to be coupled in fluid communication with the sealed space.