Effect of a lower target oxygen saturation range on the risk of hypoxaemia and elevated NEWS2 scores at a university hospital: a retrospective study.

BACKGROUND: The optimal target oxygen saturation (SpO2) range for hospital inpatients not at risk of hypercapnia is unknown. The objective of this study was to assess the impact on oxygen usage and National Early Warning Score 2 (NEWS2) of changing the standard SpO2 target range from 94-98% to 92-96%. METHODS: In a metropolitan UK hospital, a database of electronic bedside SpO2 measurements, oxygen prescriptions and NEWS2 records was reviewed. Logistic regression was used to compare the proportion of hypoxaemic SpO2 values (<90%) and NEWS2 records ≥5 in 2019, when the target SpO2 range was 94-98%; with 2022, when the target range was 92-96%. RESULTS: In 2019, 218 of 224 936 (0.10%) observations on room air and 162 of 11 328 (1.43%) on oxygen recorded an SpO2 <90%, and in 2022, 251 of 225 970 (0.11%) and 233 of 12 845 (1.81%), respectively (risk difference 0.04%, 95% CI 0.02% to 0.07%). NEWS2 ≥5 was observed in 3009 of 236 264 (1.27%) observations in 2019 and 4061 of 238 815 (1.70%) in 2022 (risk difference 0.43%, 0.36% to 0.50%; p<0.001). The proportion of patients using supplemental oxygen with hyperoxaemia (SpO2 100%) was 5.4% in 2019 and 3.9% in 2022 (OR 0.71, 0.63 to 0.81; p<0.001). DISCUSSION: The proportion of observations with SpO2 <90% or NEWS2 ≥5 was greater with the 92-96% range; however, absolute differences were very small and of doubtful clinical relevance, in contrast to hyperoxaemia for which the proportion was markedly less in 2022. These findings support proposals that the British Thoracic Society oxygen guidelines could recommend a lower target SpO2 range.

Obesity: A critical risk factor in the COVID-19 pandemic.

Obesity is an emerging independent risk factor for susceptibility to and severity of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Previous viral pandemics have shown that obesity, particularly severe obesity (BMI > 40 kg/m2 ), is associated with increased risk of hospitalization, critical care admission and fatalities. In this narrative review, we examine emerging evidence of the influence of obesity on COVID-19, the challenges to clinical management from pulmonary, endocrine and immune dysfunctions in individuals with obesity and identify potential areas for further research. We recommend that people with severe obesity be deemed a vulnerable group for COVID-19; clinical trials of pharmacotherapeutics, immunotherapies and vaccination should prioritize inclusion of people with obesity.

Impairment of high-density lipoprotein resistance to lipid peroxidation and adipose tissue inflammation in obesity complicated by obstructive sleep apnea.

CONTEXT: Obstructive sleep apnea (OSA) complicates morbid obesity and is associated with increased cardiovascular disease incidence. An increase in the circulating markers of chronic inflammation and dysfunctional high-density lipoprotein (HDL) occur in severe obesity. OBJECTIVE: The objective of the study was to establish whether the effects of obesity on inflammation and HDL dysfunction are more marked when complicated by OSA. DESIGN AND PATIENTS: Morbidly obese patients (n = 41) were divided into those whose apnea-hypoapnea index (AHI) was more or less than the median value and on the presence of OSA [OSA and no OSA (nOSA) groups]. We studied the antioxidant function of HDL and measured serum paraoxonase 1 (PON1) activity, TNFα, and intercellular adhesion molecule 1 (ICAM-1) levels in these patients. In a subset of 19 patients, we immunostained gluteal sc adipose tissue (SAT) for TNFα, macrophages, and measured adipocyte size. RESULTS: HDL lipid peroxide levels were higher and serum PON1 activity was lower in the high AHI group vs the low AHI group (P < .05 and P < .0001, respectively) and in the OSA group vs the nOSA group (P = .005 and P < .05, respectively). Serum TNFα and ICAM-1 levels and TNFα immunostaining in SAT increased with the severity of OSA. Serum PON1 activity was inversely correlated with AHI (r = -0.41, P < .03) in the OSA group. TNFα expression in SAT directly correlated with AHI (r = 0.53, P < .03) in the subset of 19 patients from whom a biopsy was obtained. CONCLUSION: Increased serum TNFα, ICAM-1, and TNFα expression in SAT provide a mechanistic basis for enhanced inflammation in patients with OSA. Decreased serum PON1 activity, impaired HDL antioxidant function, and increased adipose tissue inflammation in these patients could be a mechanism for HDL and endothelial dysfunction.

There is another way: empowering frontline staff caring for acutely unwell adults.

QUALITY PROBLEM OR ISSUE: It is estimated that only 17% of patients survive an in-hospital cardiac arrest. Medical evidence indicates that many patients show signs of deterioration during the 24 h period prior to their cardiac arrest. INITIAL ASSESSMENT: At Salford Royal NHS Foundation Trust (SRFT) 135 patients (outside critical care areas) suffered a cardiac arrest between March 2007 and April 2008. CHOICE OF SOLUTION: Quality improvement method-The breakthrough series (BTS) collaborative approach, change package-reliable manual vital signs, nurse-led response to the deteriorating patient, code red, structured ward round, ceilings of care, nurse-led do not attempt cardiopulmonary resuscitation (DNA-CPR) protocol and allocated roles. IMPLEMENTATION: The project was delivered over two phases with a total of 23 wards (12 wards in Phase One and 11 wards in Phase Two). Frontline teams worked to develop changes with the aim of reducing cardiac arrests by 50%. EVALUATION: The primary outcome measure was the number of cardiac arrests per 1000 admissions outside of critical care areas. Process and balancing measures were also used to evaluate the impact of the intervention. LESSONS LEARNED: The results showed a positive relationship between the change package and a reduction of 41% in cardiac arrests outside of critical care areas from the baseline period (April 2007-March 2008) to December 2012. The BTS model has the potential to reduce cardiac arrests without the need for initial large-scale financial investment.

A crossover study of short burst oxygen therapy (SBOT) for the relief of exercise-induced breathlessness in severe COPD.

BACKGROUND: Previous small studies suggested SBOT may be ineffective in relieving breathlessness after exercise in COPD. METHODS: 34 COPD patients with FEV1 <40% predicted and resting oxygen saturation ≥93% undertook an exercise step test 4 times. After exercise, patients were given 4 l/min of oxygen from a simple face mask, 4 l/min air from a face mask (single blind), air from a fan or no intervention. RESULTS: Average oxygen saturation fell from 95.0% to 91.3% after exercise. The mean time to subjective recovery was 3.3 minutes with no difference between treatments. The mean Borg breathlessness score was 1.5/10 at rest, rising to 5.1/10 at the end of exercise (No breathlessness = 0, worst possible breathlessness = 10). Oxygen therapy had no discernable effect on Borg scores even for 14 patients who desaturated below 90%. 15 patients had no preferred treatment, 7 preferred oxygen, 6 preferred the fan, 3 preferred air via a mask and 3 preferred room air. CONCLUSIONS: This study provides no support for the idea that COPD patients who are not hypoxaemic at rest derive noticeable benefit from oxygen therapy after exercise. Use of air from a mask or from a fan had no apparent physiological or placebo effect.

Survey of major complications of intercostal chest drain insertion in the UK.

BACKGROUND: Following reports from the National Patient Safety Agency of deaths and serious harm from intercostal chest drains (ICD) we conducted a national survey among chest physicians of their experience of harm associated with ICD. METHODS: A questionnaire was sent to 198 UK chest physicians at 148 acute hospital trusts, enquiring about current practice and any adverse incidents related to chest drains from 2003 to 2008. RESULTS: 101 of 148 trusts (68%) replied. 67 trusts reported at least one major incident involving ICD insertion. 31 Cases of ICD misplacement were reported with seven deaths. Misplaced drains were inserted in liver (10), peritoneal space (6), heart (5), spleen (5), subclavian vessels (2), colon (1), oesophagus (1) and inferior vena cava (1). 47 cases of serious lung or chest wall injuries with eight deaths and six cases of ICD placement on the wrong side with two deaths were reported. The guidewire was lost in the pleural cavity in three cases. 22 of 101 trusts required written patient consent before ICD insertion. 11 trusts had a training policy. 16 trusts had patient information literature for this procedure. The seniority of doctors permitted to insert ICDs was as follows: 30% any doctor; 27% at least 1 year post qualification; 32% at least 2 years, 11% at least 4 years. CONCLUSIONS: 67% of responding trusts had encountered major complications of ICD. The survey raised concerns about training and consent. The National Patient Safety Agency has made recommendations to address these risks which are also addressed in the 2009 update of the British Thoracic Society Pleural Disease Guideline.

Acceptance, effectiveness and safety of continuous positive airway pressure in acute stroke: a pilot study.

OBJECTIVES: To evaluate the acceptance, effectiveness in preventing upper airways obstruction, and haemodynamic effects of continuous positive airway pressure (CPAP) in acute stroke. METHODS: Twelve patients (4 M, and 8 F; mean (SD), 75.2 (5.5) years) within 48 h of acute stroke onset underwent: (1) sleep studies (1st night: auto-CPAP mode; 2nd night: diagnostic); (2) nocturnal non-invasive blood pressure studies (1st night during CPAP; 2nd night during spontaneous breathing (SB)); and (3) daytime cerebral blood flow velocity measurement in middle cerebral artery (FV) with transcranial Doppler during SB and with CPAP (5, 10, 15 cm H(2)O). RESULTS: Ninety percent, 60% and 50% of stroke patients had a respiratory disturbance index (RDI) of >or=5, >or=10 and >or=15 events per hour, respectively (18.2 (11.3)). CPAP acceptance was 84%; 42% used CPAP more than 6h and 42% between 1-3h with a mean use of CPAP of 5.2h (4.0). Compared to SB, CPAP reduced, though not significantly, RDI, time with SaO(2)<90%, mean blood pressure and mean blood pressure dips (10 mm Hg)/h. Compared with SB, any level of CPAP progressively and significantly reduced systolic and mean FV; drop in diastolic FV was significant at CPAP10 and CPAP15. The partial pressure of end-tidal CO(2) was significantly lowered by all levels of CPAP. CONCLUSIONS: According to this pilot study, CPAP is reasonably well tolerated by patients with acute stroke for at least one night. Despite its possible beneficial effect on obstructive sleep-disordered breathing and blood pressure variability, CPAP use in acute stroke should be still considered with caution due to possible harmful haemodynamic effects at higher pressures.

Anthracofibrosis, bronchial stenosis with overlying anthracotic mucosa: possibly a new occupational lung disorder: a series of seven cases From one UK hospital.

Anthracofibrosis, which was recently defined as bronchial stenosis with overlying anthracotic mucosa, has been infrequently reported in Asia as a complication of tuberculosis (TB). It has not been reported in the United Kingdom or the United States, or, to our knowledge, in non-Asian patients. We have identified seven cases of patients presenting to a single teaching hospital in the northwest of England over a 13-year period. Only one patient had a history of TB, but six of the seven patients had a history of occupational dust exposure, including one patient with pneumoconiosis. It is possible that anthracofibrosis is an exaggerated endobronchial form of the much more common condition of anthracosis in coal miners and other workers who have been exposed to mineral dusts. Our study suggests that this is essentially a benign condition, although it may progress very slowly, leading to gradually progressive bronchial stenosis. The diagnosis is important because most patients have clinical, radiologic, and bronchoscopic changes that are highly suspicious of malignancy.

PHOX2B mutation-confirmed congenital central hypoventilation syndrome: presentation in adulthood.

Congenital central hypoventilation syndrome (CCHS) typically presents in the newborn period. A case series of five adults is presented, each heterozygous for a documented polyalanine expansion mutation in the PHOX2B gene and evidence of nocturnal alveolar hypoventilation. All cases had symptoms in childhood, but survived to adulthood without ventilatory support. After identification of physiologic compromise, artificial ventilation was initiated. These adults have the mildest of the CCHS-related PHOX2B polyalanine expansion mutations, coding for only five extra alanines; three of the adults have affected offspring. Report of these cases should lead to a more rapid identification of CCHS presenting in adulthood.

Effect of upper airway obstruction on blood pressure variability after stroke.

Approx. 60% of acute stroke patients have periods of significant UAO (upper airway obstruction) and this is associated with a worse outcome. UAO is associated with repeated fluctuation in BP (blood pressure) and increased BP variability is also associated with a poor outcome in patients with acute stroke. UAO-induced changes in BP, at a time when regional cerebral perfusion is pressure-dependent in areas of critically ischaemic brain, could explain the detrimental effect of UAO on outcome in these patients. The aim of the present study was to examine the relationship between UAO and BP variability in patients with acute stroke. Twelve acute stroke patients and 12 age-, sex- and BMI (body mass index)-matched controls underwent a sleep study with non-invasive continuous monitoring of BP to assess the impact of UAO on BP control after stroke. Stroke patients had significantly more 15 mmHg dips in BP/h than the controls (51 compared with 6.7 respectively; P<0.004). Stroke patients also demonstrated significantly higher BP variability than the controls (26.8 compared with 14.4 mmHg; P<0.001). There were significantly more 15 mmHg dips in BP/h in stroke patients who had significant UAO than those who did not (85.7 compared with 29.5 respectively; P<0.032). Furthermore, stroke patients without UAO (RDI <10, where RDI is respiratory disturbance index) had significantly more 15 mmHg dips in BP/h than the controls (29.5 compared with 6.7 respectively; P<0.037). There was a positive correlation between the severity of UAO (RDI) and 15 mmHg dips in BP/h (r=0.574, P<0.005) in stroke patients. Our results suggest that UAO alone does not explain BP variation post-stroke, but it does play an important role, particularly in determining the severity of the BP fluctuation.