The use of off-the-shelf stent grafts for thoracic endovascular aortic repair of type A dissections is limited by variability in both the length of the ascending aorta and the location of the ...proximal intimal tear. This experimental study aimed to assess the feasibility of using a physician-modified thoracic aortic stent graft to treat acute type A dissection by a transapical cardiac approach.
The experiments were performed on six cadaveric human heart, ascending aorta, aortic arch, and descending aorta specimens. Fenestration was fashioned in each standard tubular Valiant thoracic stent graft (Valiant Captivia; Medtronic Vascular, Santa Rosa, Calif) to match the anatomy of each specimen. Stent grafts of sufficient length were selected to cover the entire ascending aorta and aortic arch. Stent graft diameters in proximal sealing zones were oversized by 5% to 10%. The length of the fenestration was the distance between the left subclavian artery and the proximal edge of the origin of the brachiocephalic trunk with an additional 10 mm. The diameter of the scallop was that of the brachiocephalic trunk with an additional 5 mm on all sides. The length of the covered portion of the stent graft was the distance between coronary arteries and the proximal edge of the origin of the brachiocephalic trunk. Two lateral radiopaque markers were positioned to delineate the distal and lateral edge of the scallop. Another 3-cm radiopaque marker was sutured onto the sheath to ensure accurate radiologic positioning of the scallop on the outer curve of the aorta. The left ventricle and the thoracic aorta were connected to a benchtop aortic pulsatile flow model. A 5-mm 30-degree lens was introduced through the left subclavian artery to monitor the procedure. The customized stent graft was deployed by a transapical approach under fluoroscopic control.
Median duration of stent graft modification was 21 minutes (range, 17-40 minutes). All attempts to deploy the homemade proximal scalloped stent graft by a transapical approach were successful. Completion angiography demonstrated patency of the supra-aortic trunks and of the coronary arteries in all cases. Macroscopic evaluation did not identify any deterioration of the customized stent graft.
The use of physician-modified stent grafts is feasible for thoracic endovascular aortic repair of type A dissection by a transapical approach in this model.
So far, the endovascular revolution has not included the routine management of type A dissection. We confirm with this experimental study the feasibility of physician-customized proximal scalloped stent grafts by a transapical approach. This methodology enhances accurate positioning of the scallop, provides a rapid and suitable strategy using an “on-the-shelf” endograft, and allows coverage of a greater proportion of dissected aorta and intimal tear from the sinotubular junction to the descending aorta.
Summary
Background: Congenital cleft palate (CP) is a common and painful surgical procedure in infants. CP repair is associated with the risk of postoperative airway obstruction, which may be ...increased with administration of opioids, often needed for analgesia. No described regional anesthesia technique can provide adequate pain control following CP repair in infants. The primary aim of this prospective and descriptive study was to observe the effectiveness of bilateral maxillary nerve blocks (BMB) using a suprazygomatic approach on pain relief and consumption of rescue analgesics following CP repair in infants. Analgesic consumption was compared to retrospective data. Complications related to this new technique in infants were also reviewed.
Methods: The landmarks and measurements recently defined in a three‐dimensional study using computed tomography in infants were used. After general anesthesia, a BMB was performed bilaterally with 0.15 ml·kg−1 0.2% ropivacaine in infants scheduled for CP repair. Postoperative analgesia, administration of rescue analgesics, adverse effects, and time to feed were recorded in the 48‐h period following surgery and compared to retrospective data.
Results: Thirty‐three children, mean age 5 ± 1.8 months and weight 8.3 ± 1.2 kg, were studied. Eighteen patients out of 33 (55%) did not require additional opioids intra‐operatively, vs two out of 20 (10%) without block. None needed morphine postoperatively, and intravenous nalbuphine was required in only six children (18%), vs 16 (80%) without block. Median time to feed was 8 h (range 2–24 h), vs 13 h (4–25) without block. No technical failure or complication related to the BMB was reported.
Conclusion: BMB using a suprazygomatic approach seems to improve pain relief, to decrease peri‐operative consumption of opioids, and to favor early feeding resumption after CP repair in infants.
Background. Fast reduction of serum free light chain (FLC) levels correlate with renal recovery in cast nephropathy. Because convection has the capacity to remove proteins of higher molecular ...weights, we hypothesized that haemodiafiltration (HDF) would be superior to haemodialysis (HD) for FLC clearance.
Methods. We retrospectively identified all renal replacement therapy (RRT) sessions performed in multiple myeloma patients with pre- and post-treatment FLC measurements during a 2-year period. Using kinetic modelling, we calculated reduction percentages corrected for net ultrafiltration, effective clearances, net mass removal and Kt/V for both kappa (κ) and lambda (λ) serum FLC.
Results. We analysed 27 (10 HD and 17 HDF) RRT sessions realized in a total of six subjects. HDF resulted in higher FLC removal rates when compared to HD. Moreover, high-efficiency (i.e. substitution volume > 15 L/session) HDF demonstrated median efficient FLC clearances roughly twice superior to high-flux HD for both κ (59.0 versus 33.8 mL/min, respectively; P < 0.01) and λ (40.5 versus 19.7 mL/min, respectively; P = 0.02) FLC. In post-dilution HDF treatments, corrected FLC reduction percentages positively correlated with substitution volumes. Total plasma proteins increased during RRT in the HDF group.
Conclusions. This preliminary quantitative study demonstrates the superiority of high-efficiency HDF over high-flux HD for serum FLC removal in multiple myeloma patients on RRT. No negative impact on total plasma proteins was noted.
A maxillary nerve block using external anatomic landmarks is a safe regional anesthesia for adults. However, the classic approach to the nerve may be difficult in infants. To use this block in ...infants, we describe the anatomical landmarks needed to reach the foramen rotundum area using the suprazygomatic route.Computed tomographic scans of 55 infants (mean age, 8.5 months; range, 1 week to 16 months) without any malformation were retrospectively evaluated using multimodal and multiplanar software. For each side, the distances and angles from the skin to the greater wing of the sphenoid and to the foramen rotundum area (representing the maxillary nerve) were measured in the axial and oblique planes.The distances from the skin at the frontozygomatic angle to the greater wing of the sphenoid in the axial plane and the foramen rotundum area in the oblique plane are 24.1 mm +/- 2.7 and 47.4 mm +/- 4.1, respectively. From the skin landmark, the direction of the trajectory was oriented 19.3 +/- 5.3 and 8.7 +/- 2.9 degrees forward. These distances and angles must be slightly adapted for infants younger than 6 months, although none of these parameters were correlated with age during the period studied.This anatomic study based on computed tomographic scan information may be useful for clinical application of the truncal maxillary nerve block in infants using the suprazygomatic route.
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