Pre-operative administration of butorphanol mitigates emergence agitation in patients undergoing functional endoscopic sinus surgery: A randomized controlled clinical trial

BackgroundThis study explored the effectiveness of pre-operative intravenous injection of butorphanol in the alleviation of emergence agitation (EA) in patients undergoing functional endoscopic sinus surgery (FESS).MethodsPatients (n = 708) were randomized into two groups. The butorphanol group (Group B, n = 358) received butorphanol infusion (20 ug/kg) before anesthesia induction, while the control group (Group C, n = 350) received an equal volume of normal saline infusion. General anesthesia was induced with sufentanil, propofol, and rocuronium, and was maintained with sevoflurane and remifentanil. Vasoactive drugs maintained the hemodynamic indices within 20% of the baseline.ResultsThe incidence of EA was significantly lower in Group B than that in Group C (Group B vs. C: 24.3% vs. 31.4%, respectively; P = 0.034). The times to spontaneous breathing (26.5 min vs. 23.7 min, P = 0.011), verbal response (36.0 min vs. 33.4 min, P = 0.012), and extubation (31.0 min vs. 28.7 min, P = 0.025) were longer in Group B, and the grade of cough (0.33 vs. 0.43, P = 0.024) at extubation in Group B was lower than that in Group C (P = 0.024). The mean arterial pressure at the end of the operation (P = 0.004) and at 5 min after extubation (P = 0.008) was higher and hypotension was less prominent (0.6% vs. 2.6%, P = 0.030) in Group B.ConclusionPre-operative intravenous injection of butorphanol decreased the incidence of EA after FESS and provided smooth and hemodynamically stable emergence without extending the stay in post-anesthesia care unit.Clinical trial registrationhttps://www.clinicaltrials.gov/, identifier NCT03398759

A 0.5358-Approximation for Bandpass-2

The Bandpass-2 problem is a variant of the maximum traveling salesman problem arising from optical communication networks using wavelength-division multiplexing technology, in which the edge weights are dynamic rather than fixed. The previously best approximation algorithm for this NP-hard problem has a worst-case performance ratio of 227/426. Here we present a novel scheme to partition the edge set of a 4-matching into a number of subsets, such that the union of each of them and a given matching is an acyclic 2-matching. Such a partition result takes advantage of a known structural property of the optimal solution, leading to a 70−2√/128≈0.5358-approximation algorithm for the Bandpass-2 problem

A 26-32GHz 6-bit Bidirectional Passive Phase Shifter with 14dBm IP1dB and 2.6° RMS Phase Error for Phased Array System in 40nm CMOS

This paper presents a 26-32GHz 6-bit bidirectional passive vector modulation phase shifter in 40nm CMOS for phased array systems. The passive phase shifter consists of a capacitor-free Lange-coupler based IQ generator and a differemtial power combiner. The symmetric design allows bidirectional signal propagation for flexible system configuration. Sizes of the passive switches are optimized to achieve the optimum trade-off between bandwidth and linearity. The overall phase shifter covers a range of 360° with 5.625° resolution and the RMS phase error is between 1.8° and 2.6°. It exhibits less than 0.22dB magnitude imbalance and &lt;2.5° phase imbalance between forward and inverse propagation mode.</p

Improved Parameterized and Exact Algorithms for Cut Problems on Trees

We study the Multicut on Trees and the Generalized Multiway Cut on Trees problems. For the Multicut on Trees problem, we present a parameterized algorithm that runs in time O ∗(ρk), where ρ = √√2 + 1 \u3c 1.554 is the positive root of the polynomial x4 − 2x2 − 1. This improves the current-best algorithm of Chen et al. that runs in time O ∗(1.619k). For the Generalized Multiway Cut on Trees problem, we show that this problem is solvable in polynomial time if the number of terminal sets is fixed; this answers an open question posed in a recent paper by Liu and Zhang. By reducing the Generalized Multiway Cut on Trees problem to the Multicut on Trees problem, our results give a parameterized algorithm that solves the Generalized Multiway Cut on Trees problem in time O ∗(ρk)

Multiple Anesthesia/Surgery Cannot Impair Reference Memory in Adult Mice

Postoperative cognitive dysfunction increases mortality and morbidity in perioperative patients. Numerous studies have demonstrated that multiple surgery/anesthesia during the neurodevelopmental period affects cognitive function, whereas a single anesthesia/surgery rarely causes cognitive dysfunction in adults. However, whether adults who undergo multiple anesthesia/surgery over a short period will experience cognitive dysfunction remains unclear. In this study, central nervous system inflammation and changes in cholinergic markers were investigated in adult mice subjected to multiple laparotomy procedures over a short period of time. The results showed that despite the increased expression of IL-6 and TNF-α in the hippocampus after multiple operations and the activation of microglia, multiple anesthesia/surgery did not cause a decline in cognitive function in adult mice. There were no changes in the cholinergic markers after multiple anesthesia/surgery