The variation of FiO2 with circuit type and peak inspiratory flow rate during non-invasive respiratory support using domiciliary ventilators and its significance during the COVID-19 pandemic.

Background: The COVID-19 pandemic has resulted in increased admissions with respiratory failure and there have been reports of oxygen failure and shortages of machines to deliver ventilation and Continuous Positive Airway Pressure (CPAP). Domiciliary ventilators which entrain room air have been widely used during the pandemic. Poor outcomes reported with non-invasive respiratory support using ventilators which lack an oxygen blender could be related to an unreliable Fraction of inspired O2 (FiO2). Additionally, with concerns about oxygen failure, the variety of ventilator circuits used as well as differing peak inspiratory flow rates (PIFR) could impact on the FiO2 delivered during therapy with domiciliary ventilators. Methods: In a series of bench tests, we tested the effect of choice of circuit and different PIFR on the FiO2 achieved during simulation of ventilation and CPAP therapy using domiciliary ventilators. Results: FiO2 was highly dependent upon the type of circuit used with circuits with an active exhalation valve achieving similar FiO2 at lower oxygen flow rates than circuits using an exhalation port. During CPAP therapy, high PIFR resulted in significantly lower FiO2 than low PIFR. Conclusions: This study has implications for oxygen usage as well as delivery of non-invasive respiratory support during therapy with domiciliary ventilators when these are used during the second wave of COVID-19.

An observational study of Pseudomonas aeruginosa in adult long-term ventilation.

Introduction: Pseudomonas aeruginosa increases morbidity and mortality in respiratory disease. To date the long-term ventilation population does not have clear guidelines regarding its management. Method: We undertook a retrospective observational study in a regional long-term ventilation population (837 patients). We defined the primary outcome as P. aeruginosa isolation. In addition positive cultures for copathogens (Serratia, Proteus species, Stenotrophomonas, Burkholderia cepacia complex and nontuberculous mycobacteria) were recorded. Logistic regression and odds ratios were calculated. Results: 17.6% of the cohort isolated P. aeruginosa, and this pathogen was cultured more frequently in patients with a tracheostomy (logistic regression coefficient 2.90, p≤0.0001) and cystic fibrosis/bronchiectasis (logistic regression coefficient 2.48, p≤0.0001). 6.3% of patients were ventilated via tracheostomy. In the P. aeruginosa positive cohort 46.9% of patients were treated with a long-term macrolide, 36.7% received a nebulised antibiotic and 21.1% received both. Tracheostomised P. aeruginosa positive patients received a nebulised antibiotic more frequently (OR 2.63, 95% CI 1.23-5.64, p=0.013). Copathogens were isolated in 33.3% of the P. aeruginosa cohort. In this cohort patients with a tracheostomy grew a copathogen more frequently than those without (OR 2.75, 95% CI 1.28-5.90). Conclusions: P. aeruginosa isolation is common within the adult long-term ventilation population and is significantly associated with tracheostomy, cystic fibrosis and bronchiectasis. Further research and international guidelines are needed to establish the prognostic impact of P. aeruginosa and to guide on antimicrobial management. The increased risk of P. aeruginosa should be considered when contemplating long-term ventilation via tracheostomy.

Developing an intrasalivary gland botox service for patients receiving long-term non-invasive ventilation at home: a single-centre experience.

INTRODUCTION: Sialorrhoea is a debilitating symptom in neurological disease and there is a growing literature for the use of intrasalivary gland Botulinum Toxin (botox) injections in its management. However, provision of intrasalivary gland botox remains inconsistent and sialorrhoea is often poorly controlled in motor neuron disease (MND).Sialorrhoea in association with bulbar dysfunction can cause intolerance of non-invasive ventilation (NIV) and respiratory infection, so its treatment is critical within a home ventilation service (HVS).This treatment can also be used to enable tracheostomy cuff deflation to facilitate weaning from ventilation. We report on the outcomes of intrasalivary gland botox in our HVS. METHODS: In 2015, we set up an intrasalivary gland botox service for patients under our HVS. Under ultrasound guidance, we injected submandibular gland(SMG), parotid gland (PG) or both. RESULTS: 109 intrasalivary gland botox procedures were performed in 72 patients. Diagnostic groups included MND 32Cerebral Palsy 8 and Weaning 14. Glands injected were, SMG (6%), PG (47%) and both (47%). The majority (84%) received the Dysport preparation with mean dose 273 units. 94% were ultrasound guided. 81% of injections resulted in a positive treatment effect, with 47% patients requesting repeat injections. Complications were angioedema (0.9%) and worsening dysphagia (3.7% following SMG injection). Mean survival following treatment was 40 months with 53% patients still alive. CONCLUSIONS: Intrasalivary gland botox appears effective across a range of neurological conditions requiring long-term NIV with few complications. Dysphagia may be an important complication of SMG injection. A randomised controlled trial may help establish the evidence base.

An investigation into hospital prescribers' knowledge and confidence to provide high-quality, sustainable respiratory care.

The number and range of inhaler combinations and brand names has increased significantly over recent years, making prescribing more complex. Inhalers contribute 3% of the NHS's carbon footprint, therefore appropriate inhaler prescribing, use and disposal could contribute significantly towards the NHS's target of net zero carbon emissions by 2040. We developed a survey to assess prescriber knowledge of inhaled medications, inhalation devices and environmental impacts of inhalers. One-hundred and two secondary care prescribers from one NHS trust responded. Knowledge of the contents and device types of inhalers, and of the environmental impacts of inhalers was lacking. Only 9% of respondents discuss the environmental impact of inhalers with patients and 13% have discussed inhaler disposal with patients, but 46% of respondents expressed that they would educate patients about the environmental impacts of inhalers if they were provided with education and support to do so.

Case Report: Renal potassium wasting in SARS-CoV-2 infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with many potentially fatal complications. Renal involvement in various forms is common in addition to serum electrolyte disturbances. Early reports suggest that hypokalaemia may frequent those with SARS-CoV-2 infection and various aetiological factors may cause this electrolyte disturbance. A Chinese retrospective study has demonstrated renal potassium wasting in patients infected with SARS-CoV-2, however, it is not known if these patients were receiving diuretic therapy which may be a contributing factor. This case report illustrates an example of renal potassium wasting in SARS-CoV-2 infection in the absence of diuretics and extra-renal mechanisms with important lessons learned.

Improved survival following ward-based non-invasive pressure support for severe hypoxia in a cohort of frail patients with COVID-19: retrospective analysis from a UK teaching hospital.

Since the outbreak of COVID-19 in China in December 2019, a pandemic has rapidly developed on a scale that has overwhelmed health services in a number of countries. COVID-19 has the potential to lead to severe hypoxia; this is usually the cause of death if it occurs. In a substantial number of patients, adequate arterial oxygenation cannot be achieved with supplementary oxygen therapy alone. To date, there has been no clear guideline endorsement of ward-based non-invasive pressure support (NIPS) for severely hypoxic patients who are deemed unlikely to benefit from invasive ventilation. We established a ward-based NIPS service for COVID-19 PCR-positive patients, with severe hypoxia, and in whom escalation to critical care for invasive ventilation was not deemed appropriate. A retrospective analysis of survival in these patients was undertaken. Twenty-eight patients were included. Ward-based NIPS for severe hypoxia was associated with a 50% survival in this cohort. This compares favourably with Intensive Care National Audit and Research Centre survival data following invasive ventilation in a less frail, less comorbid and younger population. These results suggest that ward-based NIPS should be considered as a treatment option in an integrated escalation strategy in all units managing respiratory failure secondary to COVID-19.

Eosinophils and effusion: a clinical conundrum.

Can you diagnose this eosinophilic patient with a pleural effusion? http://ow.ly/8G1530dJdbZ.

Managing urinary incontinence in adults with bronchiectasis.

BACKGROUND: Urinary incontinence has a negative impact on quality of life and often remains untreated due to low levels of self-reporting. Urinary incontinence is seen in cystic fibrosis associated bronchiectasis but little data are available for non-cystic fibrosis associated bronchiectasis. METHOD: In 2007 a new non-cystic fibrosis bronchiectasis service for patients aged 18 years and over was started within the Newcastle upon Tyne Hospitals NHS Foundation Trust. During the establishment of a new adult bronchiectasis service, patients were specifically asked about symptoms of incontinence, and if incontinence was identified then patients were referred for specialist continence assessment and management, in line with current good practice guidelines. The study relates only to those female patients who were referred to the continence service. RESULTS: In this audit 116 patients attended the bronchiectasis service from 2009-2010; 76 were female, of these 55% had urinary incontinence, describing dramatic effects on quality of life. Prior to intervention the duration of symptoms of urinary incontinence for more than 5 years was 87.5%, with 40% of patients describing symptoms of more than 10 years duration without seeking medical attention. Following intervention from the nurse consultant for continence care, 80% of patients who were referred were discharged with an improvement in symptoms of urinary incontinence. CONCLUSION: This audit highlights the importance of specifically asking about urinary incontinence when assessing patients with adult bronchiectasis.

Morton's neuroma: diagnostic accuracy, effect on treatment time and costs of direct referral to ultrasound by primary care physicians.

BACKGROUND: The first-line treatment for symptomatic Morton's neuroma in our hospital is a perineural ultrasound-guided injection of corticosteroid and local anaesthetic (USI). The NHS has recently implemented 18-week referral-to-treatment targets. When GPs specifically suggest a diagnosis of Morton's neuroma there are two referral pathways in our hospital: direct referral to radiology for USI (limited slots) or referral to the specialist foot and ankle clinic. Patients with less specific referral letters are also evaluated in clinic and referred for USI as appropriate. METHODS: A retrospective audit was performed reviewing referral letters from general practitioners (GPs) in 2005-2006. A comparison was made between the referral pathways for time-to-treatment (TTT), accuracy of GP diagnosis, and cost implications. RESULTS: In the directly referred group, the median TTT was 99 days, compared to 206 days for patients who went via a foot and ankle clinic (P < 0.001). Of 57 patients with a GP diagnosis of Morton's neuroma, 40 (70%) had the diagnosis confirmed on USI compared to 44 of 64 (69%) patients referred by a foot and ankle surgeon, showing no significant difference between the groups (P = 0.87). CONCLUSION: For patients with features highly suggestive of a Morton's neuroma, direct referral from primary care for USI had a similar accuracy to referral from a specialist hospital clinic and the time-to-treatment was significantly shorter. The mean waiting time of this group was within the 18-week government target without any changes to our current radiology protocols.