Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic

BACKGROUND: During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study\u27s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines. METHODS: We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March-31 May 2020. The prior 1-year control period (1 March-31 May 2019) was obtained to account for seasonal variation. FINDINGS: There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI -24.3% to -20.7%, p\u3c0.0001). Embolisation of ruptured aneurysms declined with 1170-1035 procedures, respectively, representing an 11.5% (95%CI -13.5% to -9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI -28.0% to -22.1%, p\u3c0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile. INTERPRETATION: There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction

Bowel perforation by a peritoneal dialysis catheter: report of two cases

Abstract Background Complications of peritoneal dialysis (PD) such as pain and catheter leakage are frequently reported. Delayed bowel perforation of a PD catheter is a rare adverse event but a serious complication associated with significant mortality. Bowel perforation of a PD catheter is difficult to differentiate from PD-related peritonitis and likely to result in a delay in diagnosis. Here, we report two cases of bowel perforation after PD catheter insertion by the stepwise initiation of PD using the Moncrief and Popovich technique (SMAP) and peritoneal wall anchor technique (PWAT). Case presentation The first case was a 53-year-old woman with end-stage renal disease (ESRD) due to diabetic nephropathy and a history of entero-adhesiolysis. She underwent PD catheter insertion by the SMAP with PWAT. Four months after PD catheter insertion, the catheter was found to perforate sigmoid colon. The second case was a 57-year-old woman with ESRD due to large polycystic kidney disease. She underwent the same procedure. After exteriorization of the catheter, she developed peritonitis due to perforation of the catheter tip into the bowel. Both patients were safely removed the catheter with uneventful recovery. Conclusion We reported two cases of a rare complication of PD catheter. The SMAP method, PWAT, enlarged kidneys and migration of the lower cuff may be risk factors of bowel perforation of a PD catheter

Ultrafast light-driven simultaneous excitation of coherent terahertz magnons and phonons in multiferroic BiFeO3

The ultrafast switching of magnetization in multiferroic materials by a femtosecond laser could provide various advantages in photonics and magnonics. An efficient approach to control the light-matter interaction is the modulation of ultrafast coherent magnons and phonons in the high-frequency range. Spontaneous Raman andinfraredspectrarevealtheexcitationofmagnonsandopticalphononsinmultiferroicBiFeO3 inthesub-fewterahertz range. However, coherent control of such quasiparticles has not been achieved yet. In this study, we demonstrate that linearly polarized laser pulses simultaneously excite coherent magnons [out-of-plane ( ) and in-plane ( ) cyclone modes] and optical phonon (E mode) in BiFeO3. Experimental results in conjugation with phenomenological theory, by considering three uniformly distributed magnetic domains, reveal that impulsive stimulated Raman scattering is responsible for the generation of coherent magnons and phonons in BiFeO3. The observation of these terahertz magnon and optical phonon modes paves the way for the development of ultrafast magnetoelectro-optical devices

Excitation of coherent optical phonons in iron garnet by femtosecond laser pulses

We employed femtosecond pump-probe technique to investigate the dynamics of coherent optical phonons in iron garnet. A phenomenological symmetry-based consideration reveals that oscillations of the terahertz T2g mode are excited. Selective excitation by a linearly polarized pump and detection by a circularly polarized probe confirm that impulsive stimulated Raman scattering (ISRS) is the driving force for the coherent phonons. Experimental results obtained from ISRS measurements reveal excellent agreement with spontaneous Raman spectroscopy data, analyzed by considering the symmetry of the phonon modes and corresponding excitation and detection selection rules