A Biomechanical Study of Laparoscopic 4S-Modified Roeder and Weston Knot Strength in 3-0 Polyglactin 910 and 3-0 Polydioxanone

Comparison between intracorporeal and extracorporeal ligations in a laparoscopic ovariectomy model in dogs

OBJECTIVE

To compare the influence of extracorporeal and intracorporeal ligations on the duration of and complications associated with laparoscopic ovariectomy in dogs.

STUDY DESIGN

Prospective randomized experimental study.

ANIMALS

Healthy intact female dogs (n = 18).

METHODS

The left and right ovarian pedicles of dogs undergoing laparoscopic ovariectomy were randomly assigned to intracorporeal (n = 18) or extracorporeal (n = 18) ligation groups. Surgeries were performed by two American College of Veterinary Surgeons (ACVS) diplomates and two ACVS residents. The time required to place extracorporeal and intracorporeal ligations, duration of surgery, and intraoperative complications were compared between ligation techniques. Postoperative complications were recorded.

RESULTS

The time required for intracorporeal ligation (17.3 ± 8.7 minutes) did not differ from that required for extracorporeal ligation (15.1 ± 6.1 minutes; P = .38). The total duration of surgery was 102.7 ± 28.7 minutes including portal placement and veterinary student closure of incisions. Ligation of the ovarian pedicle was successful in 16 of 17 dogs. Intraoperative hemorrhage occurred in three dogs, and postoperative complications were noted in three dogs, without apparent difference between ligation techniques.

CONCLUSION

No difference was identified between extracorporeal and intracorporeal ligations of ovarian pedicles.

CLINICAL SIGNIFICANCE

This study does not provide evidence to support one ligation technique rather than the other.

In vitro holding strength of the laparoscopic Miller's knot compared with open Miller's knot, open surgeon's throw, and laparoscopic surgeon's throw in a vascular pedicle model

OBJECTIVE

To compare in vitro knot holding strength of the laparoscopic Miller's knot (LMK), open Miller's knot (MK), open surgeon's throw (Sx), and laparoscopic surgeon's throw (LSx) in a vascular pedicle model when used as the first throw for vascular ligation.

STUDY DESIGN

Experimental study.

SAMPLE POPULATION

Ten constructs each of the Miller's knot and surgeon's throw performed openly and laparoscopically with 2-0 polyglyconate suture.

METHODS

Knot holding strengths of the LMK, MK, LSx, and Sx knots were evaluated on balloon dilation catheters used as vascular pedicle models. Laparoscopic knots were tied in a laparoscopic box trainer. Knot constructs were pressure tested to failure. Results were compared by Kruskal-Wallis and Steel-Dwass comparisons.

RESULTS

Both MK and LMK had mean leakage pressures above 300 mm Hg. The MK leaked at higher pressure than all other knots, including the LMK (P < .001). The LMK leaked at greater pressures compared with the Sx and the LSx (P < .001). No difference was detected between leaking pressures of the Sx and the LSx (P = .226), with both leaking at pressures below 40 mm Hg.

CONCLUSION

The LMK created a more secure first throw compared with the Sx and leaked at supraphysiologic pressures.

CLINICAL SIGNIFICANCE

The LMK has excellent knot holding strength on a vascular pedicle model and may be further evaluated for clinical application.