Caroline Patterson

BTS/ICS guideline for the ventilatory management of acute hypercapnic respiratory failure in adults

### Principles of mechanical ventilation #### Modes of mechanical ventilation Recommendation 1. Pressure-targeted ventilators are the devices of choice for acute NIV (Grade B). Good practice points #### Choice of interface for NIV Recommendation 2. A full face mask (FFM) should usually be the first type of interface used (Grade D). Good practice points #### Indications for and contra-indications to NIV in AHRF Recommendation 3. The presence of adverse features increase the risk of NIV failure and should prompt consideration of placement in high dependency unit (HDU)/intensive care unit (ICU) (Grade C). Good practice points #### Monitoring during NIV Good practice points #### Supplemental oxygen therapy with NIV Recommendations 4. Oxygen enrichment should be adjusted to achieve SaO2 88–92% in all causes of acute hypercapnic respiratory failure (AHRF) treated by NIV (Grade A). 5. Oxygen should be entrained as close to the patient as possible (Grade C). Good practice points

The effect of applying NICE guidelines for the investigation of stable chest pain on out-patient cardiac services in the UK

BACKGROUND The National Institute for Health and Clinical Excellence (NICE) recently released guidelines for the investigation of chest pain of recent onset. There is no published data regarding their impact on out-patient cardiac services. AIM This study was undertaken to assess the likelihood of coronary artery disease (CAD) in Rapid Access Chest Pain Clinic (RACPC) patients and the resultant investigation burden if NICE guidance was applied. METHODS Five hundred and ninety-five consecutive patients attending two RACPCs over 6 months preceding release of the NICE guidelines [51% male; median age 55 (range 22-94) years] were risk stratified using NICE criteria and the resultant investigations evaluated. RESULTS One hundred and six (18%) patients had a likelihood of CAD <10%, 123 (21%) between 10% and 29%, 175 (29%) between 30% and 60%, 141 (24%) between 61% and 90% and 50 (8%) >90%. NICE would have recommended 443 (74%) patients for no cardiac investigation, 10 (2%) for cardiac computed tomography (CCT), 69 (12%) for functional cardiac testing and 73 (12%) for invasive angiography. Relative to existing practice, there would have been a trend towards reduced functional cardiac testing (-24%, P = 0.06), no significant change in CCT (43%, P = 0.436) and a significant increase in invasive angiography (508%, P < 0.001). The cost of investigations recommended by NICE would have been £15,881 greater than existing practice. CONCLUSION This study suggests patients attending RACPC will have a greater likelihood of CAD than predicted by NICE. Differences between recommended investigations and existing practice will guide investment in cardiac services. Individual hospitals should assess their RACPC cohorts prior to implementing the NICE guidelines.

Clinical outcomes when applying NICE guidance for the investigation of recent-onset chest pain to a rapid-access chest pain clinic population

Objective To describe the clinical outcomes of patients for whom National Institute for Health and Care Excellence (NICE) recent-onset chest pain guidance would not have recommended further investigation, compared with those of patients where further investigation would have been recommended. Methods 557 consecutive patients with recent-onset chest pain attending rapid-access chest pain clinics (RACPC) in two district general hospitals over a 9-month period were retrospectively reviewed. Likelihood of coronary artery disease (CAD) was calculated according to NICE-defined modified Diamond–Forrester criteria. Patients were categorised into those for whom NICE guidelines recommend (NICE-Y) and do not recommend (NICE-N) further investigation. Main outcome measures were subsequent diagnosis of significant CAD and major adverse cardiac events (MACE) at 6 months. Results 187/557 (33.6%) patients comprised NICE-Y group, with 370/557 (66.4%) in NICE-N group. 360/370 (97.3%) of NICE-N group would have been excluded from further investigation due to non-anginal chest pain. Of 92/557 (16.5%) patients subsequently diagnosed with significant CAD, 35/557 (9.5%) were from NICE-N group versus 57/557 (30.5%, p<0.0001) from NICE-Y group. Of 11 patients experiencing at least one MACE, 7/557 (1.9%) were from NICE-N group, versus 4/557 (2.1%, p=1.000) from NICE-Y group. Conclusions The rigid application of NICE chest pain guidance to a RACPC population may result in up to two-thirds of patients being excluded from further cardiac investigation. Potentially, up to 10% of these patients may subsequently be diagnosed with significant CAD, with up to 2% potentially experiencing a major adverse cardiac event.

Indications and interventional options for non-resectable tracheal stenosis

Non-specific presentation and normal examination findings in early disease often result in tracheal obstruction being overlooked as a diagnosis until patients present acutely. Once diagnosed, surgical options should be considered, but often patient co-morbidity necessitates other interventional options. Non-resectable tracheal stenosis can be successfully managed by interventional bronchoscopy, with therapeutic options including airway dilatation, local tissue destruction and airway stenting. There are common aspects to the management of tracheal obstruction, tracheomalacia and tracheal fistulae. This paper reviews the pathogenesis, presentation, investigation and management of tracheal disease, with a focus on tracheal obstruction and the role of endotracheal intervention in management.

British Thoracic Society/Intensive Care Society Guideline for the ventilatory management of acute hypercapnic respiratory failure in adults

The British Thoracic Society (BTS) published the guideline ‘The use of non-invasive ventilation in acute respiratory failure’ in 2002.1 This was in response to trials that had demonstrated that non-invasive ventilation (NIV) was an alternative to invasive mechanical ventilation (IMV) in life-threatening respiratory acidosis due to acute exacerbations of chronic obstructive pulmonary disease (AECOPD). It drew attention to evidence that, when NIV was used in the less severely unwell patient, it also limited progression to more severe respiratory failure.2 The trial also demonstrated the feasibility, of delivering NIV on general medical or admission wards that had enhanced support and when staff were provided with ongoing training. In subsequent years, NIV has been shown to deliver better rather than equivalent outcomes to invasive ventilation in AECOPD and better evidence has accumulated for the use of NIV in non-COPD disease in the intervening years. Repeated national audits have, however, raised concerns that expected patient benefit is not being delivered and have pointed to a number of process deficiencies.3–5 There is also the risk, in the absence of justifying trial evidence, that the preferred use of NIV in AECOPD might be extended to all hypercapnic patients, irrespective of circumstance or underlying disease process. That this is a real risk might be inferred from the BTS audits where the indication for NIV was not COPD in over 30% of cases.3 ,4 NIV development in the UK has been largely outside the organisational ‘umbrella’ of critical care. This may have adversely affected resource allocation and contributed to a lack of integration in NIV and IMV patient pathways. Other unintended consequences might be a restriction on access to invasive ventilation and delay in the development of extended applications of NIV, such as accelerating extubation and its use in the management of …

The consequences of applying NICE chest pain guidelines to an acute medical population: a role for cardiac computed tomography

BACKGROUND Cardiac computed tomography (CCT) is a well-validated investigation for the non-invasive assessment of coronary artery disease (CAD). The National Institute for Clinical Excellence (NICE) have recently released guidelines incorporating CCT into the diagnostic algorithm for chest pain of recent onset. AIM To assess the frequency of eligibility for CCT in medical admissions with suspected cardiac chest pain using criteria defined by NICE. DESIGN A retrospective, observational study, set in a teaching hospital acute medical unit. METHODS A total of 198 consecutive patients admitted over a 4-month period with suspected cardiac chest pain (57% male; mean age 63.5 years) were assessed for eligibility for CCT based on NICE guideline criteria. RESULTS Of the 198 patients admitted, 65 (33%) patients were excluded by a raised troponin I or ischaemic ECG changes; 100 (51%) patients were excluded by pain categorized as non-anginal and 171 (86%) patients were excluded by a modified Diamond Forrester score outside the range 10-29%. Applying NICE criteria to this population ultimately resulted in 2 (1%) patients recommended for CCT, 12 (6%) for functional cardiac testing and 17 (9%) for invasive angiography. CONCLUSION Applying current NICE guidelines for chest pain of recent onset to medical admissions results in a lesser uptake of CCT than functional testing and invasive angiography. If the NICE guidelines are revised to include patients with an intermediate pre-test probability of CAD, CCT may have a greater role.

United Kingdom military aeromedical evacuation in the post-9/11 era.

BACKGROUND Recent UK military operations in support of the fight against terrorism have resulted in UK military casualties. Movement of these casualties through the military medical chain requires a highly sophisticated aeromedical evacuation capability with worldwide reach. Recognition of the determinants of evacuation allows development to ensure optimal future configurations of military aeromedical evacuation services. METHODS The database recording aeromedical evacuations undertaken by the Royal Air Force was searched to provide demographic and clinical data for evacuations between 1 April 2003 and 31 March 2010. Diagnoses leading to evacuation were categorized according to International Classification of Diseases codes. RESULTS There were 21,477 medical evacuations undertaken. Analysis demonstrated 85.9% were for men and 86.5% were for military personnel, of whom 72.0% were in the army. The most common reasons for evacuation in military patients were musculoskeletal/connective tissue disorders (N = 9192; 50.0%), trauma (N = 1303; 7.1%), and mental health disorders (N = 1151; 6.3%). The most common reasons for evacuation in nonmilitary patients were musculoskeletal/connective tissue disorders (N = 734; 23.8%), genitourinary disorders (N = 325; 10.5%), and circulatory disorders (N = 255; 8.3%). Nontraumatic diagnoses were the determinants of evacuation in 92.9% of military and 95.1% of nonmilitary patients; 17.8% of trauma patients and 0.5% of nontrauma patients utilized high-dependency care. DISCUSSION The UK aeromedical evacuation system must have the capacity to evacuate large numbers of patients with nontraumatic diagnoses, but also the flexibility to accommodate smaller, more variable numbers of higher dependency trauma patients. The military medical chain must continually review the differing requirements of civilian patients transferred within their aeromedical system.

Trainee concerns regarding the Specialty Certificate Examination: results of a British Thoracic Society national survey

As aspiring respiratory physicians are aware, The Federation of Royal Colleges of Physicians of the UK (FRCPUK) has introduced Specialty Certificate Examinations (SCEs) to complement workplace-based assessments. Successful completion of the SCE in Respiratory Medicine is a prerequisite for Certificate of Completion of Training for all UK respiratory trainees whose specialist training began during or after August 2007. The SCE comprises two papers, each lasting 3 h and containing 100 questions in a ‘best of five’ format. Delivery and marking of the examination is computer-based. The FRCPUK has worked in partnership with specialist societies, including the British Thoracic Society (BTS), to optimise examination validity and reliability. Analyses of SCE performance have been reported by the …

Deep vein thrombosis and pulmonary embolism in the military patient.

Objectives Venous thromboembolism (VTE), encompassing deep vein thrombosis and pulmonary embolism, is a common, potentially lethal condition and a cause of long-term morbidity and functional limitation. This paper is a clinical review focused on military epidemiology, evidence-based recommendations for prevention, diagnosis and management of VTE and occupational considerations in a military population. Methods A literature review was conducted through Pubmed and Embase for systematic reviews, meta-analyses and clinical trials relating to VTE. Guidelines from the National Institute for Health and Care Excellence, British Thoracic Society and the American College of Chest Physicians were reviewed and recommendations considered. Results Acute morbidity from VTE can range from limb pain and swelling to life-threatening cardiovascular compromise. Long-term sequelae include postthrombotic syndrome, chronic thrombosis and pulmonary hypertension. Diagnosis should follow a validated pathway depending on the patients prerest probability. The management of the condition should vary with attention to risk stratification. Discussion Prompt initiation of anticoagulation reduces symptoms, rates of recurrent VTE and death but treatment must be balanced against the risk of major haemorrhage. Military operations expose personnel to a unique combination of risk factors for VTE and operating in austere environments can increase the challenge of diagnosis, prognostication and management. Furthermore, there are implications for troop attrition, operational readiness and return to work.

The feasibility of nurse-led assessment in acute chest pain admissions by means of coronary computed tomography

Background: Cardiac computed tomography (CCT) is a non-invasive imaging technique for the diagnosis of coronary artery disease (CAD). The National Institute for Health and Clinical Excellence (NICE) recommend CCT for selected patients in the assessment of chest pain of recent onset. Aims: To assess the feasibility and utility of CCT in a nurse-led, protocol-based assessment of chest pain. Methods: Patients admitted over 4 months with suspected angina were assessed for eligibility for CCT by a specialist nurse. Eligibility was defined by: a likelihood of CAD < 90%, no features of acute coronary syndrome, no contra-indications to the scanning process, and the ability to give written consent. An age and sex-matched historical cohort (for whom CCT was unavailable) was compared with the CCT cohort with regard to the diagnosis or exclusion of CAD at 3 months post-discharge from hospital. Results: Of 198 patients admitted, 98 were identified as eligible for CCT. Of these, 37 were recommended for alternative management on cardiologist review, 18 declined consent, 23 were unable to be scanned within 24 h prior to discharge and 14 underwent CCT. CAD was diagnosed or excluded in 14/14 patients undergoing CCT. CAD was diagnosed or excluded in 11/14 patients investigated without CCT, leaving 3/14 patients with no clear diagnosis. Conclusion: This study suggests nurses may be trained to assess patients for CCT within agreed protocols. In the UK it is likely these protocols will be based on NICE guidance. Despite potential diagnostic utility, CCT appears likely to form a small percentage of cardiac investigations undertaken.