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Carlos Roger Molinas

Publications and source records attributed to Carlos Roger Molinas.

12 recordsLinked to original sources
PubMed2006

Effect of desiccation and temperature during laparoscopy on adhesion formation in mice.

OBJECTIVE: To investigate the effects of desiccation (without cooling) and of oversaturation of the pneumoperitoneum on adhesion formation. DESIGN: Prospective randomized trial. SETTING: Academic research center. ANIMAL(S): BALB/c and NMRI female mice. INTERVENTION(S): The effect of desiccation using nonhumidified CO(2) on adhesion formation was evaluated in a laparoscopic mouse model. Body temperature (BT) was maintained at 37 degrees C using a homeothermic blanket. In addition to controls without desiccation, the effect of both hypothermia and desiccation on adhesion formation was evaluated. Subsequently the effect of oversaturating the pneumoperitoneum using a high energy gas to avoid any desiccation was studied. MAIN OUTCOME MEASURE(S): During surgery BT, pneumoperitoneum temperature, and relative humidity were monitored. Adhesions were scored after 7 days. RESULT(S): Adhesions increased with increasing levels of desiccation when BT was kept at 37 degrees C. This was prevented with humidified gas. If BT decreased, adhesions were fewer. Oversaturating the pneumoperitoneum increased adhesions due to high energy gas causing an increase in both BT and pneumoperitoneum temperature. CONCLUSION(S): Adhesions increase with desiccation and decrease when BT is reduced. Adhesions are minimized when humidified gas is used. Since desiccation is associated with cooling, its effect is generally underestimated because of the counterbalance with cooling. The concept of combining controlled intraperitoneal cooling with a rigorous prevention of desiccation might be important for clinical adhesion prevention.

Animals↗
PubMed2006

Office hysteroscopy and adenomyosis.

Adenomyosis, the heterotopic presence of endometrial glands and stroma within the myometrium, has traditionally been diagnosed by the pathologist in hysterectomy specimens. However, the recent development of high-quality non-invasive techniques such as transvaginal sonography (TVS), magnetic resonance imaging (MRI) and hysteroscopy has renewed interest in diagnosing adenomyosis in the office prior to any treatment. Hysteroscopy offers the advantage of direct visualization of the uterine cavity, and since nowadays it is performed in the office, it can be offered as a first-line diagnostic tool for evaluation of uterine abnormalities in patients with abnormal uterine bleeding and/or infertility. The available data clearly indicate that high-quality mini-hysteroscopes, saline as a distension medium, and atraumatic insertion technique are essential for the success of office hysteroscopy. The procedure is indicated in any situation in which an intrauterine anomaly is suspected; it is immediately preceded by a physical exam and a TVS to evaluate uterine characteristics, and it is followed by a second TVS to take advantage of the intracavitary fluid for a contrast image of the uterus. Although diagnostic hysteroscopy does not provide pathognomonic signs for adenomyosis, some evidence suggests that irregular endometrium with endometrial defects, altered vascularization, and cystic haemorrhagic lesion are possibly associated with the entity. In addition to the direct visualization of the uterine cavity, the hysteroscopic approach offers the possibility of obtaining endometrial/myometrial biopsies under visual control. Since they can be performed in the office, the combination of TVS, fluid hysteroscopy and contrast sonography is therefore a powerful screening tool for detecting endometrial and myometrial abnormalities in association with adenomyosis.

Ambulatory Care↗
PubMed2005

Adhesion formation and interanimal variability in a laparoscopic mouse model varies with strains.

Adhesion formation after laparoscopic surgery was evaluated in mice of different strains. More adhesions were observed in Swiss, NMRI, and BALB/c mice, with less interanimal variability in BALB/c mice. These data point to genetics effects on adhesion formation, which open new insights in its pathogenesis and indicate the importance of a careful strain selection for animal studies.

Animals↗
PubMed2004

Prospective multicentre randomized controlled trial to evaluate factors influencing the success rate of office diagnostic hysteroscopy.

BACKGROUND: Diagnostic hysteroscopy is not widely performed in the office setting, one of the reasons being the discomfort produced by the procedure. This randomized controlled trial was performed to evaluate the effects of instrument diameter, patient parity and surgeon experience on the pain suffered and success rate of the procedure. METHODS: Patients were randomly assigned to undergo office diagnostic hysteroscopy either with 5.0 mm conventional instruments (n=240) or with 3.5 mm mini-instruments (n=240). Procedures were stratified according to patient parity and surgeon's previous experience. The pain experienced during the procedure (0-10), the quality of visualization of the uterine cavity (0-3) and the complications were recorded. The examination was considered successful when the pain score was <4, visualization score was >1 and no complication occurred. RESULTS: Less pain, better visualization and higher success rates were observed with mini-hysteroscopy (P <0.0001, P <0.0001 and P <0.0001, respectively), in patients with vaginal deliveries (P <0.0001, P <0.0001 and P <0.0001, respectively) and in procedures performed by experienced surgeons (P=0.02, P=NS and P=NS, respectively). The effects of patient parity and surgeon experience were no longer important when mini-hysteroscopy was used. CONCLUSIONS: Our data demonstrate the advantages of mini-hysteroscopy and the importance of patient parity and surgeon experience, suggesting that mini-hysteroscopy should always be used, especially for inexperienced surgeons and when difficult access to the uterine cavity is anticipated. They indicate that mini-hysteroscopy can be offered as a first line office diagnostic procedure.

Adult↗
PubMed2004

Role of vascular endothelial growth factor receptor 1 in basal adhesion formation and in carbon dioxide pneumoperitoneum-enhanced adhesion formation after laparoscopic surgery in mice.

OBJECTIVE: To evaluate the role of vascular endothelial growth factor receptor-1 (VEGFR-1) in adhesion formation after laparoscopic surgery. DESIGN: Prospective, randomized study. SETTING: Academic research center. ANIMAL(S): Forty female Swiss mice. INTERVENTION(S): Adhesions were induced by standardized lesions during laparoscopy. The CO2 pneumoperitoneum was maintained for the minimum time needed to perform the lesions (10 minutes) or for a longer period (60 minutes) to evaluate basal adhesions and pneumoperitoneum-enhanced adhesions, respectively. Mice were treated either with IgG or with antibodies against VEGFR-1. MAIN OUTCOME MEASUREMENT(S): Adhesions were quantitatively and qualitatively scored after 7 days during laparotomy. RESULT(S): In IgG-treated mice, 60 minutes of CO2 pneumoperitoneum increased basal adhesions. In VEGFR-1 antibody-treated mice, basal adhesions were similar to the control group and 60 minutes of CO2 pneumoperitoneum did not increase adhesions. Therefore, in these mice, pneumoperitoneum-enhanced adhesions were lower than in IgG-treated mice. CONCLUSION(S): The data confirm that CO2 pneumoperitoneum is a cofactor in adhesion formation and demonstrate that VEGFR-1 plays a role in pneumoperitoneum-enhanced adhesions, which is consistent with a role of placental growth factor, VEGF-A, and VEGF-B in pneumoperitoneum-enhanced adhesions. These observations give new insight into the pathogenesis of adhesion formation.

Animals↗
PubMed2004

Effect of adding more than 3% oxygen to carbon dioxide pneumoperitoneum on adhesion formation in a laparoscopic mouse model.

OBJECTIVE: To investigate the effect of the addition of 3% or higher oxygen concentrations to the carbon dioxide (CO2) pneumoperitoneum. DESIGN: Prospective, randomized trial. SETTING: Academic research center. ANIMAL(S): Female Naval Medical Research Institute mice (n = 100). INTERVENTION(S): Sixty minutes of CO2 pneumoperitoneum with 0%, 3%, 6%, 9%, or 12% oxygen; induction of adhesions by the creation of standardized peritoneal lesions during laparoscopy. MAIN OUTCOME MEASURE(S): Adhesions were quantitatively and qualitatively scored after 7 days during laparotomy to determine [1] the effect of 60 minutes of CO2 pneumoperitoneum with 0%, 3%, 6%, 9%, or 12% oxygen on adhesion formation, and [2] the effect of duration of CO2 pneumoperitoneum and insufflation pressure on adhesion formation with the addition of 0%, 3%, and 12% oxygen. RESULT(S): Compared with a CO2 pneumoperitoneum with 3% oxygen, adhesion formation is greater when either no oxygen or more than 3% oxygen is added to the CO2 pneumoperitoneum. These effects persisted at higher insufflation pressures and longer duration of pneumoperitoneum, both known to increase adhesion formation with pure CO2. CONCLUSION(S): This study confirms that adhesion formation is decreased with the addition of 3% oxygen to the CO2 pneumoperitoneum. The addition of higher oxygen concentrations, however, is deleterious. Adhesions always increase with time and duration of the pneumoperitoneum.

Animals↗
PubMed2004

The rabbit nephrectomy model for training in laparoscopic surgery.

BACKGROUND: Laparoscopic surgical training is generally done with the teacher-student model using complex exercises. This study was performed to evaluate a new training model that emphasizes the repetition of simple procedures. METHODS: Laparoscopic surgery was performed in rabbits (n=200) using conventional instruments. Gynaecologists (n=10) and medical students (n=10) performed a series of exercises during 20 full days training. Nephrectomy was chosen to evaluate and score laparoscopic skills, i.e. duration of surgery and complication rate, since it mimics the surgical challenge and involves dissection of major vessels. Each surgeon performed 20 nephrectomies, alternating left and right sides. RESULTS: Duration of surgery and complications decreased with training. For duration of surgery, a two-phase exponential decay learning curve, with different decays for gynaecologists and students, was observed. Gynaecologists achieved shorter operating times than students for real and calculated times in the first procedure (P<0.0001 and P<0.0001) and for calculated time in the last procedure (P=0.001). Severe complications were more frequent in students than in gynaecologists (P=0.0003). CONCLUSION: The rabbit nephrectomy model is suitable for training in laparoscopic surgery. Since it implies the repetition of short and well-defined exercises, progression is easier to monitor and the necessity for continuous supervision is less, making training less expensive.

Animals↗
PubMed2003

Role of the plasminogen system in basal adhesion formation and carbon dioxide pneumoperitoneum-enhanced adhesion formation after laparoscopic surgery in transgenic mice.

OBJECTIVE: To evaluate the role of plasminogen activator inhibitor-1 (PAI-1), urokinase plasminogen activator (uPA), and tissue-type plasminogen activator (tPA) in adhesion formation after laparoscopic surgery. DESIGN: Prospective, randomized study. SETTING: Academic research center. ANIMAL(S): Seventy female wild-type and transgenic knockout mice for PAI-1 (PAI-1(-/-)), uPA (uPA(-/-)) or tPA (tPA(-/-)). INTERVENTION(S): Standardized lesions to induce peritoneal adhesions were performed during laparoscopy. To evaluate basal adhesions and pneumoperitoneum-enhanced adhesions, the pneumoperitoneum was maintained for 10 minutes or 60 minutes, respectively. Peritoneal biopsy samples were obtained during and after 60 minutes of carbon dioxide pneumoperitoneum. MAIN OUTCOME MEASURE(S): Adhesions were blindly scored after 7 days. Concentrations of PAI-1 and tPA were measured by using enzyme-linked immunosorbent assay. RESULT(S): In PAI-1, uPA, and tPA wild-type mice, pneumoperitoneum enhanced adhesions. Compared with wild-type mice, basal adhesions were fewer in PAI-1(-/-) mice and more in uPA(-/-) and tPA(-/-) mice. Pneumoperitoneum did not enhance adhesions in these transgenic mice. PAI-1 concentration increased after 60 minutes of pneumoperitoneum whereas tPA concentration did not change. CONCLUSION(S): Impaired fibrinolysis increases basal adhesions. The absence of pneumoperitoneum-enhanced adhesions in PAI-1(-/-), uPA(-/-), and tPA(-/-) mice and the increase in PAI-1 expression indicate that PAI-1 up-regulation by carbon dioxide pneumoperitoneum is a mechanism of pneumoperitoneum-enhanced adhesion formation.

Animals↗
PubMed2003

Role of vascular endothelial growth factor and placental growth factor in basal adhesion formation and in carbon dioxide pneumoperitoneum-enhanced adhesion formation after laparoscopic surgery in transgenic mice.

OBJECTIVE: To evaluate the role of vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) in adhesion formation after laparoscopic surgery. DESIGN: Prospective, randomized study. SETTING: Academic research center. ANIMAL(S): Female wild-type mice and transgenic mice (n = 110), expressing exclusively VEGF-A(164) (VEGF-A(164/164)) or deficient for VEGF-B (VEGF-B(-/-)) or for PlGF (PlGF(-/-)). INTERVENTION(S): Adhesions were induced during laparoscopy. To evaluate "basal adhesions" and "CO(2) pneumoperitoneum-enhanced adhesions," the pneumoperitoneum was maintained for a minimum (10 minutes) or prolonged (60 minutes) period. The role of PlGF was also evaluated by administration of antibodies. MAIN OUTCOME MEASURE(S): Adhesions were blindly scored after 7 days. RESULT(S): In all wild-type mice, CO(2) pneumoperitoneum enhanced adhesion formation. In comparison with wild-type mice, basal adhesions were higher in VEGF-A(164/164) mice and similar in VEGF-B(-/-) and PlGF(-/-) mice. Pneumoperitoneum did not enhance adhesions in any of these transgenic mice. The effects observed in PlGF(-/-) mice were confirmed in PlGF antibody-treated mice. CONCLUSION(S): The data demonstrate that the VEGF family plays a role in adhesion formation and confirm that CO(2) pneumoperitoneum enhances adhesions. VEGF-A(164) has a direct role in basal adhesions. Absence of pneumoperitoneum-enhanced adhesions in VEGF-A(164/164), VEGF-B(-/-), and PlGF(-/-) mice indicates up-regulation of VEGF-A(164), VEGF-B, and PlGF by CO(2) pneumoperitoneum as a mechanism for pneumoperitoneum-enhanced adhesion formation.

Animals↗
PubMed2003

Role of hypoxia inducible factors 1alpha and 2alpha in basal adhesion formation and in carbon dioxide pneumoperitoneum-enhanced adhesion formation after laparoscopic surgery in transgenic mice.

OBJECTIVE: To evaluate the role of hypoxia inducible factors (HIFs) 1alpha and 2alpha in adhesion formation after laparoscopic surgery. DESIGN: Prospective, randomized study. SETTING: Academic research center. ANIMAL(S): Forty Swiss/129SvJ wild-type mice and transgenic mice partially deficient for the genes encoding for HIF-1alpha (HIF-1alpha(+/-)) or HIF-2alpha (HIF-2alpha(+/-)). INTERVENTION(S): Adhesions were induced by standardized lesions during laparoscopy. To evaluate "basal adhesions" and "pneumoperitoneum-enhanced adhesions," the pneumoperitoneum was maintained for a minimum (10 minutes) or prolonged (60 minutes) period, respectively. MAIN OUTCOME MEASURE(S): Adhesions were blindly scored after 7 days. RESULT(S): In both HIF-1alpha and HIF-2alpha wild-type mice, pneumoperitoneum enhanced adhesion formation. In comparison with wild-type mice, basal adhesions were lower in HIF-1alpha(+/-) and similar in HIF-2alpha(+/-) mice. Pneumoperitoneum did not enhance adhesion formation in HIF-1alpha(+/-) or in HIF-2alpha(+/-) mice. Therefore, in comparison with the correspondent wild-type mice, pneumoperitoneum-enhanced adhesions were lower in HIF-1alpha(+/-) and HIF-2alpha(+/-) mice. CONCLUSION(S): These data confirm that CO(2) pneumoperitoneum enhances adhesion formation and indicate that this effect is mediated, at least in part, by an up-regulation of HIF-1alpha and HIF-2alpha.

Animals↗
PubMed2002

Prevention of adhesions with crystalloids during laparoscopic surgery in mice.

STUDY OBJECTIVE: To evaluate the effect of saline and Ringer's lactate solutions in preventing adhesions during laparoscopic surgery in mice. DESIGN: Prospective, randomized trial (Canadian Task Force classification I). SETTING: Academic research center. SUBJECTS: Ninety-two female Naval Medical Research Institute mice. INTERVENTION: Adhesions were induced laparoscopically by opposing bipolar lesions in the uterine horns and pelvic sidewalls, and saline or Ringer's lactate solution was added at different times during the procedure. MEASUREMENTS AND MAIN RESULTS: Adhesions were scored quantitatively and qualitatively for extent, type, and tenacity after 7 days under microscopic vision during laparotomy. After 45 minutes of pneumoperitoneum, neither solution reduced adhesion formation, but when added immediately after surgery they did (p = 0.002). Coagulation was not significantly different with addition of either solution immediately after coagulation. In the third experiment the presence of fluid during pneumoperitoneum decreased adhesion formation (p = 0.0001) but Ringer's lactate was more effective than saline (p = 0.0005). CONCLUSION: Crystalloids reduced CO(2) pneumoperitoneum-enhanced adhesion formation in a laparoscopic mouse model, but Ringer's lactate solution was more effective than saline.

Animals↗