Perioperative hypertension is a phenomenon in which a surgical patient’s blood pressure temporarily increases throughout the preoperative and postoperative periods and remains high until the patient’s condition stabilizes. This phenomenon requires immediate treatment not only because it is observed in a majority of patients who are not diagnosed with high blood pressure, but also because occurs in patients with underlying essential hypertension who show a sharp increase in their blood pressure. The most common complication following facelift surgery is hematoma, and the most critical risk factor that causes hematoma is elevated systolic blood pressure. In general, a systolic blood pressure goal of <150 mm Hg and a diastolic blood pressure goal of >65 mm Hg are recommended. This article discusses the causes of increased blood pressure and the treatment methods for perioperative hypertension during the preoperative, intraoperative, and postoperative periods, in order to find ways to maintain normal blood pressure in patients during surgery. Further, in this paper, we review the causes of perioperative hypertension, such as anxiety, epinephrine, pain, and postoperative nausea and vomiting. The treatment methods for perioperative hypertension are analyzed according to the following 3 operative periods, with a review of the characteristics and interactions of each drug: preoperative antihypertensive medicine (atenolol, clonidine, and nifedipine), intraoperative intravenous (IV) hypnotics (propofol, midazolam, ketamine, and dexmedetomidine), and postoperative antiemetic medicine (metoclopramide and ondansetron). This article focuses on the knowledge necessary to safely apply local anesthesia with IV hypnotics during facelift surgery without the assistance of an anesthesiologist.

In contrast with conventional thermal evaporation-based semiconducting oxide growth methods, gourd-like SiO x nanotubes (NTs) grown from Si substrates were achieved with incorporated Sn-embedded structures through the precontaminated SnO2 film surroundings. Interestingly, when Sn aggregations assembled as Sn nanoparticles were formed on the surface of the Si substrate, single gourd-like SiO x NTs were grown from the upper local region of the ternary alloy (Si–Sn–O) sphere, maintaining a one-to-one correspondent relationship between the ternary spheres and the Sn-embedded SiO x NTs. Both interfacial reaction-controlled and diffusion-controlled systems occurred stepwise at the smooth and rough surfaces, respectively. In addition, the elemental compositions and sizes of the final Sn-embedded SiO x NTs were influenced by the Sn concentration of the SnO2 film, the rate of In substitution by Sn in the supporting material In2O3, and the degree of carbothermal reduction of additional graphite powders.

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Balloon whisk-like and flower-like SiOx tubes with well-dispersed Sn and joining countless SiOx loops together induce intense luminescence characteristics in substrate materials. Our synthetic technique called “direct substrate growth” is based on pre-contamination of the surroundings without the intended catalyst and source powders. The kind of supporting material and pressure of the inlet gases determine a series of differently functionalized tube loops, i.e., the number, length, thickness, and cylindrical profile. SiOx tube loops commonly twist and split to best suppress the total energy. Photoluminescence and confocal laser measurements based on quantum confinement effect of the embedded Sn nanoparticles in the SiOx tube found substantially intense emissions throughout the visible range. These new concepts related to the synthetic approach, pre-pollution, transitional morphology, and permeable nanoparticles should facilitate progress in nanoscience with regard to tuning the dimensions of micro-/nanostructure preparations and the functionalization of customized applications.

SiOx structures with different diameters of a few hundreds of nanometers and/or a few micrometers are prepared using applied thermal evaporation. Subsequently, Sn quantum dot-based SiOx architectures are synthesized via the continuous steps of the carbothermal reduction of SnO2, substitution of Sn(4+) for In(3+), thermal oxidation of Si, Sn sublimation, interfacial reaction, and diffusion reaction consistent with corresponding phase equilibriums. Several crystalline and spherical-shaped Sn quantum dots with diameters between 2 and 7 nm are observed in the amorphous SiOx structures. The morphological evolution, including hollow Sn (or SnOx) sphere and wire-like, worm-like, tube-like, and flower-like SiOx, occurs stepwise on the Si substrate upon increasing the given process energies. The optical characteristics based on confocal measurements reveal the as-synthesized SiOx structures, irrespective of whether crystallinity is formed, which all have visible-range emissions originating from the numerous different-sized and -shaped Sn quantum dots permeating into the SiOx matrix. In addition, photoluminescence emissions ranging between ultraviolet and red regions are in agreement with confocal measurements. The origins of the morphology- and luminescence-controlled amorphous SiOx with Sn quantum dots are also discussed.