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Manufacturing of medicines often requires a crystallization stage. The crystallization method must be designed to produce the desired crystal form with specific shape, size distribution, and polymorphic form. This paper presents the use of process analytical technology (PAT) tools, including focused beam reflectance measurement (FBRM) probe, turbidity meter, and attenuated total reflectance (ATR) UV−vis spectroscopy, for the monitoring and detection of polymorphic transformation during the antisolvent crystallization of sodium benzoate from a propan-2-ol (IPA)/water mixture. A range of solid-state analytical (SSA) techniques including optical microscopy, scanning electron microscope (SEM), X-ray powder diffraction (XRPD), high temperature X-ray powder diffraction (HT-XRPD), solid and solution state nuclear magnetic resonance (SSNMR), infrared (IR) spectroscopy, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) confirmed the formation of a new, previously unreported channel solvate, which transforms into a channel hydrate during the antisolvent crystallization experiments. A combination of DSC and hot stage microscopy (HSM) analyses discovered the formation of a higher melting polymorphic form of sodium benzoate, which also has not yet been reported in the literature. This paper provides an illustrative example how the combination of PAT tools and SSA techniques can lead to the discovery of new polymorphic forms and can provide the conditions under which different forms of the compound sodium benzoate exist so the system can be designed to produce the desired form. [ABSTRACT FROM AUTHOR]

Background Tracheal intubation via laryngoscopy is a fundamental skill, particularly for anaesthesiologists. However, teaching this skill is difficult since direct laryngoscopy allows only one individual to view the larynx during the procedure. The purpose of this study was to determine if video-assisted laryngoscopy improves the effectiveness of tracheal intubation training. Methods In this prospective, randomized, crossover study, 37 novices with less than six prior intubation attempts were randomized into two groups, video-assisted followed by traditional instruction (Group V/T) and traditional instruction followed by video-assisted instruction (Group T/V). Novices performed intubations on three patients, switched groups, and performed three more intubations. All trainees received feedback during the procedure from an attending anaesthesiologist based on standard cues. Additionally, during the video-assisted part of the study, the supervising anaesthesiologist incorporated feedback based on the video images obtained from the fibreoptic camera located in the laryngoscope. Results During video-assisted instruction, novices were successful at 69% of their intubation attempts whereas those trained during the non-video-assisted portion were successful in 55% of their attempts (P=0.04). Oesophageal intubations occurred in 3% of video-assisted intubation attempts and in 17% of traditional attempts (P Conclusions The improved rate of successful intubation and the decreased rate of oesophageal intubation support the use of video laryngoscopy for tracheal intubation training. [ABSTRACT FROM AUTHOR]