Pseudoaneurysm: a complication of faulty technique in femoral arterial puncture

Pseudoaneurysm is a well-documented but rare complication of retrograde femoral arterial puncture. We present six patients in whom pseudoaneurysm complicated this procedure. The pseudoaneurysm arose from the superficial femoral artery in five patients and from the profunda femoris artery in one. An arteriovenous fistula also arose from the superficial femoral artery in one patient. In no patient did the pseudoaneurysm arise from the common femoral artery. Two mechanisms are postulated as to why pseudoaneurysms rarely complicate puncture of the common femoral artery.     

Validation of a prediction rule to maximize curative (R0) resection of early-stage pancreatic adenocarcinoma

Background:

The surgeon''s contribution to patients with localized pancreatic adenocarcinoma (PAC) is a margin negative (R0) resection. We hypothesized that a prediction rule based on pre-operative imaging would maximize the R0 resection rate while reducing non-therapeutic intervention.

Methods:

The prediction rule was developed using computed tomography (CT) and endoscopic ultrasound (EUS) data from 65 patients with biopsy-proven PAC who underwent attempted resection. The rule classified patients as low or high risk for non-R0 outcome and was validated in 78 subsequent patients.

Results:

Model variables were: any evidence of vascular involvement on CT; EUS stage and EUS size dichotomized at 2.6 cm. In the validation cohort, 77% underwent resection and 58% achieved R0 status. If only patients in the low-risk group underwent surgery, the prediction rule would have increased the resection rate to 92% and the R0 rate to 73%. The R0 rate was 40% higher in low-risk compared with high-risk patients (P < 0.001). High risk was associated with a 67% rate of non-curative surgery (unresectable disease and metastases).

Conclusion:

The prediction rule identified patients most likely to benefit from resection for PAC using pre-operative CT and EUS findings. Model predictions would have increased the R0 rate and reduced non-therapeutic interventions.     

Gemcitabine causes minimal modulation of carboplatin-DNA monoadduct formation and repair in bladder cancer cells

We are developing a method to identify cellular resistance to carboplatin by using accelerator mass spectrometry to measure carboplatin-DNA adducts formed from drug microdoses (～1/100th the therapeutic dose). Such an approach would be particularly useful if it is still valid in combination chemotherapy. We examined whether the addition of gemcitabine, another chemotherapeutic drug, could influence carboplatin-DNA adduct levels. There were no substantial differences in the levels of carboplatin-DNA adducts in cells upon exposure to the carboplatin/gemcitabine combination at various doses and schedules. These data demonstrate that microdosing is feasible for the characterization of carboplatin resistance when given in combination with gemcitabine.     

The functional and structural changes in the basilar artery due to overpressure blast injury

Overpressure blast-wave induced brain injury (OBI) leads to progressive pathophysiologic changes resulting in a reduction in brain blood flow, blood brain barrier breakdown, edema, and cerebral ischemia. The aim of this study was to evaluate cerebral vascular function after single and repeated OBI. Male Sprague-Dawley rats were divided into three groups: Control (Naive), single OBI (30 psi peak pressure, 1 to 2 msec duration), and repeated (days 1, 4, and 7) OBI (r-OBI). Rats were killed 24 hours after injury and the basilar artery was isolated, cannulated, and pressurized (90 cm H₂O). Vascular responses to potassium chloride (KCl) (30 to 100 mmol/L), endothelin-1 (10⁻¹² to 10⁻⁷ mol/L), acetylcholine (ACh) (10⁻¹⁰ to 10⁻⁴ mol/L) and diethylamine-NONO-ate (DEA-NONO-ate) (10⁻¹⁰ to 10⁻⁴ mol/L) were evaluated. The OBI resulted in an increase in the contractile responses to endothelin and a decrease in the relaxant responses to ACh in both single and r-OBI groups. However, impaired DEA-NONO-ate-induced vasodilation and increased wall thickness to lumen ratio were observed only in the r-OBI group. The endothelin-1 type A (ET_A) receptor and endothelial nitric oxide synthase (eNOS) immunoreactivity were significantly enhanced by OBI. These findings indicate that both single and r-OBI impairs cerebral vascular endothelium-dependent dilation, potentially a consequence of endothelial dysfunction and/or vascular remodelling in basilar arteries after OBI.     

Severe congenital absence of skin in a preterm infant

A severe case of aplasia cutis congenita in a preterm infant is described. Although major problems with thermoregulation and fluid balance were anticipated, these parameters were relatively easy to control once the patient was stabilized. Meticulous skin care and rapid formation of a membranous-like fibrous tissue layer covering the denuded areas probably played an important role in minimizing excessive fluid and heat loss. The prognosis in aplasia cutis congenita is determined by the underlying associated anomalies, the severity of skin lesions and, in our case, the maturity of the infant who died from complications of prematurity.