Biomedical subjects

P B Petratos

Publications and source records attributed to P B Petratos.

3 recordsLinked to original sources

PubMed2001

Carotid artery anastomosis with albumin solder and near infrared lasers: a comparative study.

BACKGROUND AND OBJECTIVE: Laser tissue-welding has been used for anastomosis of carotid arteries. During welding, thermal injury sustained by the vessel walls should be minimized to prevent thrombosis. Two different types of lasers were used and effects on tissue damage were studied in vitro and in vivo. STUDY DESIGN/MATERIALS AND METHODS: End-to-end anastomosis of dog carotid arteries (n = 10) was performed by using a human albumin solder (HAS) in conjunction with Nd:YAG or diode lasers (lambda = 1.32 microm and 1.9 microm, respectively). The arteries were evaluated for patency and evidence of histologic injury after 21 days. Another group of arteries was laser soldered in vitro to measure the intimal and adventitial temperatures by using thermocouples. RESULTS: The arteries repaired with the diode laser sustained significantly less thermal damage than those repaired with Nd:YAG laser, both in vitro and in vivo. In particular, the intimal temperature was significantly lower (P < 0.05) for the diode than for the Nd:YAG repairs (approximately 35 degrees C and approximately 50 degrees C, respectively). In the latter group, the patency rate was 75%, but thrombosis occurred in 75% of the specimens at 21 days. All diode anastomoses were patent and thrombosis developed in only 17% of the arteries. CONCLUSION: Use of the diode laser and albumin solders may provide a means to successfully repair carotid arteries with minimal thermal damage.

Anastomosis, Surgical↗

PubMed2001

Concentrated autologous plasma protein: a biochemically neutral solder for tissue welding.

BACKGROUND AND OBJECTIVE: Xenographic or allographic serum protein solders used for laser welding may have immunologic and/or pathogenic complications. The objective of these studies was to develop a safe, autologous solder. STUDY DESIGN/MATERIALS AND METHODS: Five methods of preparing concentrated autologous plasma protein solder (CAPPS) were evaluated. Next, the CAPPS was evaluated via (1) thermal denaturation studies using differential scanning calorimetry, (2) tissue welding studies to characterize both acute and healing properties. RESULTS: The optimal concentration method to produce CAPPS rapidly was a dialysis method using chemical (osmotic) forces. The CAPPS showed similar denaturation profiles to serum albumin (SA) solders. Acutely, CAPPS provided comparable breaking strengths to SA solders. At 7 days, there was no significant difference in breaking strength or histology between 50% human SA solder and CAPPS (using a porcine skin model). CONCLUSIONS: These studies demonstrate that the CAPPS system provides acceptable acute and chronic properties for laser welding.

Animals↗

PubMed2001

Hand-assisted demucosalized gastrocystoplasty comparing different tissue closure methods.

OBJECTIVES: To perform experiments to determine whether a new tissue sealant (SynthaSeal) could be an alternative for suture closure in minimally invasive bladder autoaugmentation gastrocystoplasty using demucosalized stomach. Alternative methods to suture closure for tissue approximation such as laser tissue welding and fibrin glue have been reported. METHODS: Minimally invasive autoaugmentation gastrocystoplasty with demucosalized stomach was performed on 14 female mongrel dogs. Two dogs were used to refine the technique. The remaining dogs were assigned to a suture group (n = 6) or a SynthaSeal group (n = 6). Anastomoses were performed using either SynthaSeal or suture. The in vivo bladder volumes and pressures of the groups were measured before and after gastrocystoplasty. The animals were studied on day 14. Samples of the anastomotic area were taken to measure the tensile strength and stress. Histologic analysis was conducted to assess tissue healing. The anastomotic time was recorded for each group. RESULTS: The tensile strength of the anastomoses in the SynthaSeal group was significantly increased (9.99 +/- 1.14 Newtons) compared with the suture group (5.66 +/- 0.97 Newtons) (P <0.05). The breaking stress comparisons and anastomosis times were equivalent between the two groups. The histologic evaluation revealed minor tissue devitalization and a normal inflammatory response in both groups. CONCLUSIONS: Minimally invasive gastrocystoplasty using demucosalized stomach can be successfully performed with SynthaSeal tissue sealant. This may provide a reliable alternative to suture closure.

Anastomosis, Surgical↗