Application of thrombin based fibrin glue and non-thrombin based batroxobin glue on intact human blood vessels: evidence for transmural thrombin activity.

An alternative method of uniting small diameter vessels to obtain tissue union while limiting the thrombogenic effect of suture placement at a vessel anastomosis involves the use of a thrombin based fibrin glue as a surgical sealant. This investigation addresses whether the in vitro application of a thrombin based glue (TG), or batroxobin glue (BG), a non-thrombin based glue made with the snake venom enzyme batroxobin, alters intravascular platelet deposition (PD) or cleaves blood fibrinogen, as measured by fibrinopeptide A (FPA) production, when the respective glue is applied to the external surface of an intact human placental artery or an artery with an anastomosis. When TG was applied to the adventitial surface of an intact vessel or an anastomosis (n = 7) of control and experimental vessels, there was a significant increase in intraluminal platelet deposition, an effect not realized with BG (n = 12, intact vessel TG p = 0.01, BG p = 0.66, anastomosis TG p <0.01, BG p <0.01). Both TG and BG significantly increased FPA levels when human whole blood was perfused through both intact vessels or vessels containing an anastomosis when compared to control vessels (intact vessel TG and BG p <0.01, anastomosis TG and BG p <0.01). Labelled thrombin studies document the rapid passage of thrombin through an intact vessel wall or vessels with an anastomosis when TG was applied to the adventitial surface of the vessel. The data suggest that TG and BG are drug delivery systems for their respective enzymes that either pass through or transfer a message across not only a surgically created anastomosis, but also an intact vessel wall.

New horizons in management of hypothermia and frostbite injury.

Diagnosing hypothermia requires a high index of suspicion. Restoring lost heat with careful attention to hemodynamics usually results in complete recovery. Frostbite is best treated by physicians who are cognizant of the pathophysiology of cold injury. Although alternative methods of intervention are being tested, rapid rewarming and anti-inflammatory agents are integral to treatment protocols.

Total mastectomy: indications and techniques.

Total mastectomy is an effective operation for patients who are candidates for a prophylactic mastectomy. This operation removes a larger percentage of breast tissue than subcutaneous mastectomy. The cosmetic results of total mastectomy with immediate reconstruction compare favorably with those of subcutaneous mastectomy.

A new photopolymerizable blood vessel glue that seals human vessel anastomoses without augmenting thrombogenicity.

A new nonbiologic photopolymerizable glue, polyethyleneglycol 400 diacrylate, was studied with respect to its mechanical and biochemical interaction with human blood vessels. Using the human placental artery model, we tested the ability of polyethyleneglycol 400 diacrylate to prevent leakage of blood at the site of vascular anastomoses, which are made porous by the presence of tissue gaps and suture puncture sites. Fibrin glue is known to augment local vessel thrombogenicity through the presence of the coagulation enzyme thrombin. We tested the effect of externally applied polyethyleneglycol 400 diacrylate (which does not contain thrombin) on luminal thrombin activity and platelet deposition from flowing human blood. At a shear rate of 312 per second and a transmural pressure of 80 cm H2O, the leakage rate of saline from human placental artery anastomoses was 1.0 +/- 1.2 ml/min (n = 8). When the same anastomoses were then glued, 7 of 8 of the anastomoses leaked less than 0.05 ml/min (p < 0.05). Platelet deposition to human vessels was not influenced by the external application of polyethyleneglycol 400 diacrylate either on intact vessels (no polyethyleneglycol 400 diacrylate, 0.51 +/- 0.28 x 10(6) platelets/cm2; with polyethyleneglycol 400 diacrylate, 0.47 +/- 0.26 x 10(6) platelets/cm2; n = 7) or at anastomoses (no polyethyleneglycol 400 diacrylate, 0.69 +/- 0.36 x 10(6) platelets/cm2; with polyethyleneglycol 400 diacrylate, 0.53 +/- 0.33 x 10(6) platelets/cm2; n = 8), p > 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

Dynamic computed tomography as an ancillary screening test for traumatic thoracic aortic injuries: a critical review.

While the divergence of opinion on the matter of diagnostic modalities will probably continue, dynamic computed tomography scans should be considered as a necessary study in assessing a possible traumatic thoracic aortic injury. The use of this modality will decrease the need for thoracic angiograms and invariably increase the yield.

Description of a novel microcomputer program to analyze left ventricular segmental wall motion during normal sinus rhythm and sinus tachycardia.

The authors have written a program to describe left ventricular (LV) regional wall motion (RWM) for a Tektronix 4051 graphic system and an MC68000, 32-bit word based microcomputer utilizing interactive graphics methods. Proper wall motion of 16 defined regions of the LV endocardial perimeter (RAO angiographic views) were computed from the magnitudes of fixed vectors fixed to analogous positions along the LV perimeter from end-diastole to end-systole (Figure 1). It was assumed that (1) LV contraction, tangential to the perimeter, produced RWM at large angles to the direction of contraction, and (2) LV contraction occurred uniformly along the anterolateral and posteromedial perimeters. All motion vectors were computed following digitization of the LV perimeters from projected images of 35-mm cineangiographic frames corrected for linear and nonlinear distortion. Digitization input was accurate to less than 0.3 mm and area computation demonstrated errors of less than 1.5%. A normal group (NG) without coronary artery (CA) disease (N = 31) defined a set of Gaussian distributed referent values for mean WM (magnitude of motion vectors) for all segments. WM amplitudes for the CA disease group (N = 125) demonstrated significant diviation in the areas supplied by occluded or stenosed coronary arteries. Qualitative and quantitative evaluation of the adequacy of coronary circulation and/or collateral vessel development could be made by inspection of WM amplitude computer plots. Proper WM was found to be highly specific for numbers and distribution of coronary arteries diseased.

Two-staged breast reconstruction in patients with symptomatic macromastia requiring mastectomy.

Patients with symptomatic macromastia undergoing mastectomy for the treatment of malignant breast disease are candidates for a two-staged operation resulting in breast reconstruction and contralateral breast reduction. Five patients with symptomatic macromastia underwent a skin-sparing mastectomy for breast disease using a modified Wise incision. The first stage of the breast reconstruction was performed with a de-epithelialized transverse rectus abdominis musculocutaneous (TRAM) flap. Second-stage breast reconstruction was conducted 4 to 6 months later when revision of the TRAM reconstructed breast and concurrent contralateral breast reduction were performed with the intent of tailoring the reduced breast to approximate the revised TRAM breast mound. Excess areola from the reduced breast was harvested and used as a full-thickness graft to reconstruct the TRAM areola complex. Patients followed for 5 to 30 months postoperatively confirm resolution of macromastia symptoms, correction of the mastectomy defect, and symmetrical breast mound creation in a timely two-staged procedure. The two-staged breast reconstruction described represents an expedient plan for patients with symptomatic macromastia requiring mastectomy for breast disease. Skin-sparing mastectomy, modified Wise pattern incisions, utilization of usually discarded areola tissue, and creation of symmetrical breast mounds during the second stage of the reconstruction highlight the salient features of this patient management paradigm.

Artificial microvascular graft thrombosis: the consequences of platelet membrane glycoprotein Ib inhibition and thrombin inhibition.

Early thrombosis of artificial microvascular grafts (AMG, grafts < or = 2 mm internal diameter) prevents their reliable clinical use. The present studies were undertaken to examine the effect of hirudin, a thrombin-specific inhibitor, and of the F(ab')2 fragment of PG-1, a monoclonal antibody (MoAb) directed against guinea pig platelet membrane glycoprotein Ib (GPIb), on AMG patency in an animal model. One-centimeter long segments of expanded polytetrafluoroethylene (ePTFE), 0.88 mm internal diameter, were serially implanted as interposition grafts in the guinea pig femoral arterial systems bilaterally. A control group was treated with 0.5 mL saline intravenously (IV) 30 minutes before limb 1 and limb 2 graft implantation. Three experimental groups were treated with 0.5 mL saline IV before limb 1 graft implantation as an animal control and with either 0.5 mL saline containing 1.25 mg/kg IV PG-1 F(ab')2, (which inhibits ristocetin-induced platelet agglutination and von Willebrand factor binding), hirudin 1 mg/kg IV, or a combination of both agents before limb 2 graft implantation. GPIb inhibition, thrombin inhibition, and the combination resulted in a significant prolongation of AMG patency (P < .005). Whereas thrombin inhibition with hirudin prolonged AMG patency similar to that observed with GPIb inhibition, the combination of GPIb and thrombin inhibition provided the overall longest prolongation of AMG patency. These results indicate that both platelet membrane GPIb and thrombin play a role in AMG thrombosis.