Search

Rationale: For veno-arterial extracorporeal membrane oxygenation (ECMO), the femoral artery is the preferred cannulation site (femoro-femoral: Vf-Af). This results in retrograde aortic flow, which increases the left ventricular afterload and can lead to severe pulmonary edema and thrombosis of the cardiac chambers. Right axillary artery cannulation (femoral-axillary: Vf-Aa) provides partial anterograde aortic flow, which may prevent some complications. This study aimed to compare the 90-day mortality and complication rates between VF-AA and VF-AF., Methods: Consecutive adult patients with cardiogenic shock who received peripheral VA-ECMO between 2013 and 2019 at our institution were retrospectively included. The exclusion criteria were refractory cardiac arrest, multiple VA-ECMO implantations due to vascular access changes, weaning failure, or ICU readmission. A statistical approach using inverse probability of treatment weighting was used to estimate the effect of the cannulation site on the outcomes. The primary endpoint was the 90-day mortality. The secondary endpoints were vascular access complications, stroke, and other complications related to retrograde blood flow. Outcomes were estimated using logistic regression analysis., Results: VA-ECMO was performed on 534 patients. Patients with refractory cardiac arrest ( n = 77 (14%)) and those supported by multiple VA-ECMO ( n = 92, (17%)) were excluded. Out of the 333 patients studied ( n = 209 Vf-Aa; n = 124 VF-AF), the main indications for VA-ECMO implantation were post-cardiotomy (33%, n = 109), dilated cardiomyopathy (20%, n = 66), post-cardiac transplantation (15%, n = 50), acute myocardial infarction (14%, n = 46) and other etiologies (18%, n = 62). The median SOFA score was 9 [7-11], and the crude 90-day mortality rate was 53% ( n = 175). After IPTW, the 90-day mortality was similar in the Vf-Aa and VF-AF groups (54% vs 58%, IPTW-OR = 0.84 [0.54-1.29]). Axillary artery cannulation was associated with significantly fewer local infections (OR = 0.21, 95% CI:0.09-0.51), limb ischemia (OR = 0.37, 95% CI:0.17-0.84), bowel ischemia (OR = 0.16, 95% CI:0.05-0.51) and pulmonary edema (OR = 0.52, 95% CI:0.29-0.92) episodes, but with a higher rate of stroke (OR = 2.87, 95% CI:1.08-7.62) than femoral artery cannulation., Conclusion: Compared to VF-AF, axillary cannulation was associated with similar 90-day mortality rates. The high rate of stroke associated with axillary artery cannulation requires further investigation., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Forty recently extracted teeth with Class II amalgam restorations with overhangs were divided into four groups of 10 teeth each. The overhangs were removed using one of the following instruments in each group: trimmer, chisel, surgical blade and reciprocating motordriven diamond tip. Instrumentation was performed until no irregularity could be detected clinically with a No. 3 explorer. The tooth-amalgam interfaces were examined by combined use of a surface measuring instrument and a scanning electron microscope. Four tracings from each specimen were recorded and the discrepancy at the tooth-restoration interface was measured. The mean score for each tooth was determined, and the results were analyzed statistically. The tooth-restoration interfaces were photographed at 140 magnification with the SEM. The results indicated that all instruments tested were effective in removing overhangs, since none of the mean discrepancies registered after instrumentation exceed 4 micron. The surgical blade, and especially the reciprocating motor-driven diamond tip eliminated overhangs better than the chisel. Both SEM photographs and the profilometric tracings revealed gaps or voids at the toothamalgam interface, ranging from 10 to 50 micron.