Respiratory Support Unit care found to significantly reduce rates of hospital mortality

2nd July 2024

Hospital mortality is significantly lower for patients in Respiratory Support Unit (RSU)-equipped hospitals than for those in non-RSU hospitals, according to a new audit report from the British Thoracic Society (BTS).

The National Respiratory Support Audit 2023 found hospital mortality in RSU-equipped hospitals was 23% compared to the 35% seen in non-RSU hospitals. However, it also revealed that while 60% of hospitals have a designated RSU, only 42% of patients requiring enhanced respiratory care were treated in such a unit due to limited capacity.

In addition, 44% of hospitals were routinely staffed at a 1:4-1:8 nurse-to-patient ratio, despite national standards recommending 1:2 nursing if starting acute non-invasive ventilation (NIV), which accounts for approximately 50% of RSU caseload. National standards also caution that enhanced care cannot be consistently delivered at 1:4-1:8.

Commenting on the findings, Dr Mike Davies, clinical audit lead at the BTS, said: ‘Our national audit found that patients in hospitals with an RSU had significantly higher survival rates, especially for patients treated in them. Treatments like acute NIV are life-saving when provided in the right setting at the right time. However, limited capacity meant that many patients were still treated in regular wards. It’s time to recognise their potential and ensure RSUs are properly resourced and staffed to transform patient care.’

‘No meaningful increase’ in enhanced care

Building on the previous National Adult NIV Audit 2019 and a successful pilot Respiratory Support Audit in 2021/22, the new BTS Respiratory Support Audit is the first national audit of enhanced respiratory care for acute hospitals in the UK.

The audit ran from 1 February to 31 March 2023, and had two parts: an organisational questionnaire, with one record to be submitted by each of 115 participating hospitals to provide information on available resources for each institution, and a patient questionnaire, which gathered one record per patient from 119 hospitals.

Key findings of the organisational audit showed that, compared to pre-pandemic studies, there has been no meaningful increase in the provision of enhanced respiratory care, and only 30% of hospitals reported having 24/7 consultant medical supervision of respiratory enhanced care.

Furthermore, central monitoring of patients’ vital signs was only available in 22% of hospitals with no designated RSU, and 64% of hospitals equipped with an RSU.

Acute hypercapnic respiratory failure treated with NIV was the most common reason for admission for enhanced respiratory care (48%), followed by acute pneumonia (16%), non-respiratory hospital capacity issues (6%) and Covid-19 (5%).

NIV was used in 63% of the cases, and high-flow oxygen therapy (HFT) for 25%. Yet, despite the high-acuity nature of HFT use (average 60% oxygen requirement), patients were more likely to receive HFT in routine, non-enhanced ward settings compared to other patients receiving enhanced care.

The patient-level audit – which considered 4,136 individual patient records from the 119 hospitals – found that even if a hospital was equipped with an RSU, only 64% of patients who required enhanced care received this care there. Escalation of patients to critical care was also extremely low at just 3% of whole cohort, even in the event of very early failure of non-invasive support at ward level.

Lower RSU mortality

Nonetheless, hospital mortality was much lower for patients in RSU-equipped hospitals compared to those in non-RSU hospitals. For example, case-mix adjustment using the Non-invasive Ventilation Outcomes (NIVO) score for patients with COPD treated with NIV showed lower mortality in enhanced care settings (33%) compared to a standard ward setting (46%). And patients with acute pneumonia had a survival rate of 64% in an RSU or equivalent setting, compared to 48% in standard wards.

In a statement, the BTS said: ‘Early findings therefore indicate that the implementation of RSUs is working well and has the potential to be transformative to the care received by respiratory patients. It will be important, however, to ensure that RSUs are recognised for the potential of their impact and that they are resourced appropriately in line with national standards.’

National improvement objectives

The BTS Respiratory Support Audit findings have been used to inform three national improvement objectives:

1. Each hospital that admits patients with acute lung disease should have an RSU or RSU equivalent to provide enhanced care. Current 60%, target 100%

2. Acute respiratory support (NIV, HFT, CPAP) for patients with acute lung disease should be delivered in an RSU or equivalent area with appropriate staffing levels (including high dependency unit and critical care areas) and should not be used routinely in unenhanced, standard ward areas. Current 49%, target >75%

3. Patients with COPD who experience early NIV failure within two days of starting in the absence of high-risk prognostic factors (e.g. if NIVO score < 5) should be discussed with critical care to consider the merits of treatment escalation. Current 17%, target >50%

The ambition of the BTS is that these national improvement objectives will ‘provide a structure for respiratory services around the UK to use as a benchmark in improving the quality of care provided for high acuity respiratory patients’, within a 12-month timeline of the audit’s publication.

Dr Paul Walker, chair of the BTS added: ‘This is a seminally important report which shows Respiratory Support Units that are appropriately organised, structured and staffed and have adequate capacity can save the lives of up to one in six people with COPD who are admitted to hospital with respiratory failure. Akin to the development of Coronary Care Units, these findings are the foundation for improving care for some of the most critically ill respiratory patients.’

Pre-existing hypertension not independently associated with in-hospital COVID-19 mortality

21st April 2022

Pre-existing hypertension does not appear to be an independent risk factor for in-hospital mortality in patients with COVID-19

Pre-existing hypertension does not appear to be an independent risk factor for in-hospital mortality in patients with COVID-19. This was the conclusion of an analysis of a COVID-19 patient registry by researchers from University College London, UK and University Medical Center Utrecht, Utrecht University, the Netherlands.

Early in the course of the COVID-19 pandemic, Chinese researchers reported that after adjustment for confounders, patients with hypertension had a two-fold increased risk of mortality compared to those without the disease.

In contrast, other Chinese work suggested that neither hypertension nor elevated blood pressure were independent risk factors for death or acute respiratory distress syndrome (ARDS)/respiratory failure, but that hypertension marginally increased the risk of severe COVID-19 infection.

Following these early reports, a 2020 systematic review analysing the effect of co-morbidities in COVID-19, concluded that underlying diseases, including hypertension, respiratory system disease and cardiovascular disease, may be risk factors for severe COVID-19 infection.

Additionally, although some studies have concluded that hypertension may be an independent risk factor for all-cause mortality in patients with COVID-19, a US study of over 2,000 patients identified several clinical and hospital-level risk factors that may be associated with death in critically ill patients with COVID-19, but this list excluded hypertension.

With some uncertainty over whether pre-existing hypertension is an independent risk factor for mortality in COVID-19, the UK team turned to the CAPACITY-COVID register, which was specifically designed to collate detailed information regarding cardiovascular risk factors and complications from COIVD-19 during hospital admission.

Participants in the database were adults and the analysis was based on the presence of confirmed COVID-19 infection and documented pre-existing hypertension. Using regression analysis, the primary outcome focused on the association between pre-existing hypertension and in-hospital mortality and models were adjusted for several factors including age, sex, diabetes and kidney disease.

Pre-existing hypertension and in-hospital mortality

The analysis included 9,197 individuals with a median age of 69 years (60.6% male) of whom, 48.3% had pre-existing hypertension.

In-hospital mortality occurred in 22% of participants with more deaths recorded in those with pre-existing hypertension (26% vs 18.2%, p < 0.001). Moreover, in the unadjusted models, the presence of pre-existing hypertension was associated with an increased odds of mortality (odd ratio, OR = 1.57, 95% CI 1.42 – 1.74). But when the models were fully adjusted for known confounders such as age, this effect was attenuated and became non-significant (aOR = 0.97, 95% CI 0.87 – 1.10).

With respect to anti-hypertensive treatment, in fully adjusted models and when the data were pooled, both angiotensin converting enzyme inhibitor (ACEi) and angiotensin receptor blocker (ARB) drugs, tended to have a protective effect on in-hospital mortality (aOR = 0.88, 95% CI 0.78 – 0.99).

The authors concluded that after appropriate adjustment and in contrast to earlier findings, pre-existing hypertension does not independently confer an increased risk of death among patients hospitalised with COVID-19. They added that despite some early concerns, the use of both ACEi and ARB drugs appeared to offer some degree of protection against in-hospital mortality.

Citation
McFarlane E et al. The impact of pre-existing hypertension and its treatment on outcomes in patients admitted to hospital with COVID-19. Hypertens Res 2022