How safe is the use of prosthetic materials in the repair of abdominal-wall defects in malnourished subjects?

Incisional hernias and abdominal-wall defects consume large amounts of healthcare resources. Use of mesh is effective in treatment of these disorders and can decrease the rate of recurrence. This experimental study focused on the safety of mesh use in the setting of malnutrition, a condition that impairs wound healing. Rats were divided into two groups: normally fed and food-restricted. An abdominal-wall defect, 2 by 2 cm, was covered with polypropylene mesh, 2.5 by 2.5 cm. After sacrifice of the rats at the 21st and 60th days, tissue samples were sent for tensiometric and histopathological studies. No significant difference in infectious complications was observed between the two groups. Tensiometry revealed no significant differences between the groups. On histopathological examination, the only difference noted was in the vascularization scores of normally fed rats. For malnourished subjects that survived after surgery, the use of polypropylene mesh appeared safe in the closure of abdominal-wall defects, with no increase in infection rate and satisfactory wound healing.     

Adherence to and gastrointestinal tolerability of monthly oral or quarterly intravenous ibandronate therapy in women with previous intolerance to oral bisphosphonates: a 12-month, open-label, prospective evaluation

BACKGROUND: Gastrointestinal (GI) symptoms and high dosing frequency have been cited as reasons for inadequate adherence to daily or weekly oral bisphosphonate therapy. Inadequate adherence may lead to poor therapeutic outcomes. OBJECTIVE: The PRIOR study evaluated adherence to and GI tolerability of monthly therapy with oral and quarterly intravenous ibandronate in postmenopausal women with osteoporosis or osteopenia. METHODS: This 12-month, multicenter, prospective, nonrandomized, open-label, noninferiority study included postmenopausal women with osteoporosis or osteopenia who had discontinued previous daily or weekly oral bisphosphonate therapy because of GI intolerance. Participants chose to receive either monthly oral ibandronate 150 mg or quarterly intravenous ibandronate 3 mg and were permitted to switch formulations once during the study. For oral treatment, adherence was assessed based on doses taken, as recorded on the case-report form; for intravenous treatment, adherence was assessed based on doses administered, as recorded by study site personnel. Participants who took >or=75% of protocol-specified doses were considered adherent. The rate of adherence to oral ibandronate was protocol defined as noninferior to that of intravenous ibandronate if the upper limit of the 2-sided 90% CI for the adjusted difference in adherence rates was >20%. At screening, participants assessed the tolerability of their previous bisphosphonate therapy using the GI Experience Survey; using the same instrument, they assessed the tolerability of ibandronate 1 month from baseline and at months 4, 7, and 10. RESULTS: Of 543 participants in the intent-to-treat population, 147 (27.1%) chose to receive oral treatment and 396 (72.9%) chose to receive intravenous treatment. The mean age of participants was approximately 66 years in both groups, and >90% of participants were white. A significantly greater proportion of participants who selected intravenous versus oral treatment had a primary diagnosis of osteoporosis (72.2% vs 57.1%, respectively; P<0.001) and a history of fracture as an adult (35.6% vs 22.4%; P >or= 0.004); significantly fewer recipients of intravenous versus oral ibandronate were currently working (29.0% vs 39.5%; P >or= 0.021). Overall, 82.9% of participants had previously received alendronate and 44.9% had previously received risedronate. Eleven participants switched from oral to intravenous therapy and 16 switched from intravenous to oral therapy during the study. In the perprotocol population, 69.7% of participants in the oral group (101/145) and 82.9% of participants in the intravenous group (325/392) were adherent to their originally selected therapy. Adherence to oral therapy fell within the prespecified boundary for noninferiority to intravenous therapy (adjusted difference: 12.4%; 90% CI, 5.1-19.7). Mean GI tolerance scores were significantly improved from screening at all subsequent assessment times in both treatment groups (P < 0.001); >75% of participants had a >or=10% increase in GI tolerability scores from screening. Both dosing regimens were generally well tolerated. CONCLUSION: Self-selected monthly oral or quarterly intravenous ibandronate therapy was associated with high adherence rates among these postmenopausal women with osteoporosis or osteopenia who had previously discontinued oral bisphosphonate treatment because of GI intolerance.     

Effect of types of resection and manipulation on trocar site contamination after laparoscopic colectomy: An experimental study in rats with intraluminal radiotracer application

Background The etiology and incidence of port-site metastases after laparoscopic surgery for colorectal cancer remain unknown. The purpose of this experimental study was to detect and quantify the amount of contamination at the port-site by means of a method utilizing radiolabelled colloid particles following extra- or intracorporeal laporoscopic resection of cecum. Methods Prior to experimental surgery, we obtained a high concentration of luminal colonic radiotracer activity by per anum application of sulphur colloid molecules labelled with Tc-99m pertechnetate. In three main groups of rats, we either resected a portion of cecum extracorporeally or intracorporeally, or did no resection. Each main group was further divided into two subgroups, in which the manipulations were either autraumatic or traumatic. We excised trocar sites as 2 cm doughnuts after completion of the surgical procedure. We used gamma camera imaging to quantify the amount of radioactive contamination at trocar sites. The background corrected trocar site activity for each rat was calculated. Activities exceeding the maximum background activity were accepted as trocar site contamination. Results We detected an overall incidence of contamination in 44% of rats. This rate were 71% and 17% in traumatic and atraumatic subgroups. The resection itself increased the rate and intensity of contamination, as well (p = 0.04). The most intensive contamination was detected in the intracorporeal resection with traumatic manipulation subgroup (p = 0.0007). Conclusions Both the presence of resection and manipulative trauma seemed to be increasing the rate and intensity of the radioactive activity at the trocar site. When traumatic manipulatiun was exercised, the contamination was so intense that the type of resection did not differ. We concluded that our scintigraphic method would be useful in the intraoperative detection of port site contamination by the tumor cells, and that surgeons would take some preventive measures to prevent future port-site metastases.     

Laparoscopic Adjustable Gastric Banding in a Morbidly Obese Patient with Situs Inversus Totalis

Laparoscopic adjustable gastric banding is a commonly performed bariatric operation worldwide. The presence of an anatomical variation like situs inversus demands preoperative assessment and preparedness on the part of the surgeon. We report a laparoscopic gastric banding performed on a morbidly obese patient with situs inversus totalis in the Kingdom of Saudi Arabia.     

Biomechanical comparison of occipitoatlantal screw fixation techniques

OBJECT: The stability provided by 3 occipitoatlantal fixation techniques (occiput [Oc]-C1 transarticular screws, occipital keel screws rigidly interconnected with C-1 lateral mass screws, and suboccipital/sublaminar wired contoured rod) were compared. METHODS: Seven human cadaveric specimens received transarticular screws and 7 received occipital keel-C1 lateral mass screws. All specimens later underwent contoured rod fixation. All conditions were studied with and without placement of a structural graft wired between the skull base and C-1 lamina. Specimens were loaded quasistatically using pure moments to induce flexion, extension, lateral bending, and axial rotation while recording segmental motion optoelectronically. Flexibility was measured immediately postoperatively and after 10,000 cycles of fatigue. RESULTS: Application of Oc-C1 transarticular screws, with a wired graft, reduced the mean range of motion (ROM) to 3% of normal. Occipital keel-C1 lateral mass screws (also with graft) offered less stability than transarticular screws during extension and lateral bending (p < 0.02), reducing ROM to 17% of normal. The wired contoured rod reduced motion to 31% of normal, providing significantly less stability than either screw fixation technique. Fatigue increased motion in constructs fitted with transarticular screws, keel screws/lateral mass screw constructs, and contoured wired rods, by means of 19, 5, and 26%, respectively. In all constructs, adding a structural graft significantly improved stability, but the extent depended on the loading direction. CONCLUSIONS: Assuming the presence of mild C1-2 instability, Oc-C1 transarticular screws and occipital keel-C1 lateral mass screws are approximately equivalent in performance for occipitoatlantal stabilization in promoting fusion. A posteriorly wired contoured rod is less likely to provide a good fusion environment because of less stabilizing potential and a greater likelihood of loosening with fatigue.     

Activated protein C attenuates intestinal reperfusion-induced acute lung injury: an experimental study in a rat model

BACKGROUND: Activated protein C (APC) is a serine protease with anticoagulant and anti-inflammatory activities. APC has been shown to attenuate local deleterious effects of ischemia/reperfusion (I/R) injury in many organs. We aimed to investigate the effects of APC on lung reperfusion injury induced by superior mesenteric occlusion. METHODS: Male Wistar-Albino rats were allocated into 4 groups: (1) sham-operated group, laparotomy without I/R injury (n = 12); (2) sham + APC group, identical to group 1 except for APC treatment (n = 12); (3) intestinal I/R group, 60 minutes of ischemia followed by 3 hours of reperfusion (n = 12); and (4) I/R + APC-treated group, 100 microg/kg injection of APC intravenously, 15 minutes before reperfusion (n = 12). Evans blue dye was injected into half of the rats in all groups. We assessed the degree of pulmonary tissue injury by measuring activities of oxidative and antioxidative enzymes, as well as nitrate (NO(3)(-))/nitrite (NO(2)(-)) levels, biochemically. We evaluated acute lung injury (ALI) by establishing pulmonary neutrophil sequestration and ALI scoring histopathologically. Pulmonary edema was estimated by using Evans blue dye extravasation and wet/dry ratios. The plasma levels of proinflammatory cytokines and D-dimer were measured. RESULTS: APC treatment significantly reduced activities of oxidative enzymes and nitrate/nitrite levels in the lung tissues, and plasma levels of proinflammatory cytokines and D-dimer, and also significantly increased activities of antioxidative enzymes (P < .05). Pulmonary neutrophil sequestration and ALI scores were decreased significantly with APC administration (P < .05). In addition, APC treatment significantly alleviated pulmonary edema (P < .05). CONCLUSIONS: This study clearly showed that APC treatment significantly attenuated the lung reperfusion injury. Further clinical studies are required to clarify whether APC has a useful role in the reperfusion injury during particular surgeries in which I/R-induced organ injury occurs.     

The role of functional imaging in the diagnosis and management of late normal tissue injury

Normal tissue injury after radiation therapy (RT) can be defined based on either clinical symptoms or laboratory/radiologic tests. In the research setting, functional imaging (eg, single-photon emission computed tomography [SPECT], positron-emission tomography [PET], and magnetic resonance imaging [MRI]) is useful because it provides objective quantitative data such as metabolic activity, perfusion, and soft-tissue contrast within tissues and organs. For RT-induced lung, heart, and parotid gland injury, pre- and post-RT SPECT images can be compared with the dose- and volume-dependent nature of regional injury. In the brain, SPECT can detect changes in perfusion and blood flow post-RT, and PET can detect metabolic changes, particularly to regions of the brain that have received doses above 40 to 50 Gy. On MRI, changes in contrast-enhanced images, T(1) and T(2) relaxation times, and pulmonary vascular resistance at different intervals pre- and post-RT show its ability to detect and distinguish different phases of radiation pneumonitis. Similarly, conventional and diffusion-weighted MRI can be used to differentiate between normal tissue edema, necrosis, and tumor in the irradiated brain, and magnetic resonance spectroscopy can measure changes in compounds, indicative of membrane and neuron disruption. The use of functional imaging is a powerful tool for early detection of RT-induced normal tissue injury, which may be related to long-term clinically significant injury.