Non-equilibrium molecular simulations of thin film rupture.

The retraction of thin films, as described by the Taylor-Culick (TC) theory, is subject to widespread debate, particularly for films at the nanoscale. We use non-equilibrium molecular dynamics simulations to explore the validity of the assumptions used in continuum models by tracking the evolution of holes in a film. By deriving a new mathematical form for the surface shape and considering a locally varying surface tension at the front of the retracting film, we reconcile the original theory with our simulation to recover a corrected TC speed valid at the nanoscale.

The Changing Face of Head and Neck Cancer; How the Head and Neck One-Stop Clinic Has Evolved Since Conception.

Purpose: The purpose of this study was to compare the patient journey through the head and neck clinic across 13 years of service improvement. We aimed to compare pick-up rates of cancer; number of patients receiving tissue diagnoses at first visit; and number of patients who were discharged on their first visit. Methods: In the one-stop head and neck cancer clinic, the demographic data, investigations and outcomes for 277 patients who attended in 2004 were compared to those of 205 patients who attended in 2017. The number of patients receiving ultrasonography and fine needle aspiration cytology was compared. Patient outcomes were analysed: specifically, the number discharged on first visit and the number of malignancies diagnosed. Results: The pick-up rate for malignancy from 2004 to 2017 has remained stable (17.3% vs 17.1%). The number of patients receiving ultrasound has remained stable from 264 (95%) in 2004 to 191 (93%) in 2017. The number undergoing FNA has decreased from 139 (50%) to 68 (33%) (p < 0.01). The number of patient's discharged on the first visit has significantly increased from 82 (30%) in 2004 to 89 (43%) in 2017 (p < 0.01). Conclusion: The one-stop clinic provides an effective and efficient means of head and neck lump assessment. Since inception of this service, the accuracy of diagnostic investigation has improved over time.

The Variable Rate Intravenous Insulin Infusion Protocol.

Insulin use among inpatients is high and associated with severe and regular medication errors. An initial baseline audit showed a wide variation in the prescription of intravenous insulin within the trust. These included variation in the choice of fluid prescribed, electrolyte levels not consistently checked, handwritten illegible prescriptions, and varying parameters set for adjustment of the prescription. A Variable Rate Intravenous Insulin Infusion protocol (VRIII)) was introduced to standardize intravenous insulin prescription throughout the trust by all members of the clinical team. We looked at and measured uptake and effects of the VRIII protocol in improving standardization of insulin prescription for inpatients on insulin at St George's NHS trust. The protocol was uploaded to the intranet to allow access 24 hours a day and the staff educated about it. The VRIII protocol was routinely used successfully throughout the trust. Any initial problems were addressed through education of clinical staff. The protocol has shown decreased prescribing and administrative errors, whilst demonstrating good glucose and electrolyte control. Use of a standardized protocol helps reduce medication errors and demonstrates good glycaemic control. Regular and continued education of clinical staff is necessary to maintain its efficacy.

An unusual case of abdominal distension: pneumoperitoneum secondary to pneumomediastinum in a patient with chronic obstructive pulmonary disease.

A 68-year-old lady with end-stage chronic obstructive pulmonary disease presented with vomiting and abdominal pain. On examination her abdomen was grossly distended, diffusely tender and hyper-resonant. Imaging showed dilated loops of bowel and free air in the abdomen with no intestinal perforation. The free abdominal air had come down from the thorax by dissecting down around the oesophagus. A pneumomediastinum was present in her chest, secondary to her extensive emphysematous disease. She was treated conservatively and her pneumomediastinum resolved several weeks later, with subsequent resumption of intestinal motility and return to premorbid function. Surgical intervention would not have helped her condition.

How we do it: training in airway management for a head and neck unit.

Experience and confidence in the management of the airway is highly variable among junior surgical trainees, who are usually the first on scene when problems arise, particularly out of hours. Juniors must possess the skills required to recognise and institute appropriate management in an airway emergency. We describe a local training programme, an airway equipment trolley, and a protocol for recognition, stabilisation, and management, in case of an airway emergency.