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RESEARCH: Martin J Wildman, Colin Sanderson, Jayne Groves, Barnaby C Reeves, Jon Ayres, David Harrison, Duncan Young, and Kathy Rowan Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study BMJ 2007; 335: 1132 [Abstract] [Full text]

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Chronic Obstructive Pulmonary Disease and intensive care admission: Prognostic pessimism may be related to inexperience

Paul Frost, Matt P Wise, Consultant in Intensive Care Medicine   (3 November 2007)

BNP testing may help to decide who to admit to a critical care unit.

Martina Montagnana, Giuseppe Lippi   (8 November 2007)

CAOS- grouping COPD and Asthma may underestimate the discrepancy between predicted and actual prognosis for COPD. What about 'COS'?

Suveer Singh, Daffyd Lloyd, Tasneem Katawala, James Harris, Radha Sabharatnam   (13 November 2007)

Pessimism; not all bad?

Olga M Peters-Polman, Jan G Zijlstra, Jaap E Tulleken, John H Meertens, Jack J Ligtenberg   (21 November 2007)

Impact of non-invasive ventilation

David H Dewar   (30 November 2007)

Different intensivists with different approaches

M Samer Abdalla   (1 December 2007)

Pessimistic optimism?

Jeremy Groves   (4 December 2007)

Considering factors other than prognosis in admissions to ITU.

Jane Gibbins, Colette M Reid, Consultant in Palliative Medicine, Gloucester, Karen Forbes, Professor of Palliative Medicine, Bristol   (5 December 2007)

Is it time to reset our perceptions of baseline survival in COPD patients invasively ventilated following the CAOS study?

Andrew J Burtenshaw, Chris Gough, Helga Fichter, Neil Crooks   (5 December 2007)

ICU for all?

J R MacDonald   (6 December 2007)

Physician assessment can be improved but may still be best

Ian A Rowe   (12 December 2007)

Prognostic pessimism in COPD

Martin J Wildman   (17 December 2007)

Should ITU admissions policies be reconsidered?

Nathaniel M Broughton   (1 April 2008)

Chronic Obstructive Pulmonary Disease and intensive care admission: Prognostic pessimism may be related to inexperience 3 November 2007
Paul Frost, Consultant in Intensive Care Medicine Critical Care Directorate, University Hospital of Wales, Heath Park, Cardiff Wales CF14 4XW, Matt P Wise, Consultant in Intensive Care Medicine Send response to journal: Re: Chronic Obstructive Pulmonary Disease and intensive care admission: Prognostic pessimism may be related to inexperience	We read with interest the study by Wildman et al, which demonstrated that UK intensive care doctors were unduly pessimistic about outcomes for patients with Chronic Obstructive Pulmonary Disease (COPD) or asthma admitted into the intensive care unit (ICU). The authors suggested that such unwarranted prognostic pessimism might lead to potential survivors with these illnesses being denied admission to the ICU.[1] However the study does not state the grade of the admitting ICU doctor or how admission decisions were reached. This is important, as clinical acumen and prognostic ability are likely to improve with intensive care experience and medical seniority. However, in the UK decisions to admit to the ICU are often made by trainee doctors without direct involvement of either the consultant from the referring team or the consultant responsible for the ICU.[2] We would hypothesise that if, as is likely, the ICU admitting doctors surveyed in this study were predominantly trainees, then their pessimistic prognoses may in part reflect inexperience in intensive care outcomes generally rather than for COPD and asthma in particular. This deficiency in the ICU admission process has been recognised by the National Institute for Health and Clinical Excellence (NICE), which has recently recommended that decisions to admit patients to ICU should involve both the consultant from the referring team and the consultant responsible for the ICU.[3] If implemented this would be an important safeguard in ensuring that potential survivors from serious illnesses such as COPD were not denied appropriate care. Paul Frost Consultant in Intensive Care Medicine, Critical Care Directorate, University Hospital of Wales, Cardiff, Wales CF14 4XW Paulrachel@btopenworld.com Matt P Wise Consultant in Intensive Care Medicine Competing interests: None Declared 1. Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D et al. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study BMJ, Nov 2007; doi:10.1136/bmj.39371.524271.55 2. Cullinane M, Findlay G, Hargreaves C and Lucas S (2005) An Acute Problem. National Confidential Enquiry into Patient Outcome and Death. London 3. National Institute for Health and Clinical Excellence. Acutely ill Patients in Hospital. http://guidance.nice.org.uk/CG50 Accessed 2nd November 2007 Competing interests: None declared
BNP testing may help to decide who to admit to a critical care unit. 8 November 2007
Martina Montagnana, Post-doc fellow in clinical biochemistry Sez. Chimica Clinica, Dip. Scienze Morfologico-Biomediche, Università di Verona, Italy, Giuseppe Lippi Send response to journal: Re: BNP testing may help to decide who to admit to a critical care unit.	Predicting the probability of short term survival is crucial when assessing the benefits of intensive care (1). Heart failure, asthma, and chronic obstructive pulmonary disease (COPD) are syndromes where dyspnea and wheezing are overlapping symptoms, and therefore, these syndromes are often difficult to be differentiated (2). Moreover, COPD and congestive heart failure (CHF) are frequently present in the same patient, both representing a negative prognostic factor. This subgroup of patients presents a substantial therapeutic opportunity for the initiation and chronic administration of angiotensin-converting enzyme inhibitors and beta-blockers therapy, as well as other CHF management strategies (2). Since increased secretion of the brain natriuretic peptide (BNP) occurs early in the course of HF, BNP testing may be a valuable tool for risk stratification (3). The lack of BNP elevation in response to the moderate increase in pulmonary arterial pressure that can be observed in patients with isolated COPD is of important clinical value. Elevated BNP values in patients with COPD are usually not related to airways obstruction by itself, but most probably to an associated left ventricular dysfunction. BNP levels may hence become an important test in the differential diagnosis of dyspnea, especially when chest radiography and transthoracic echocardiography findings are noncontributory or poorly contributory (4). Moreover, a correlation was found between BNP levels and different parameters, as pulmonary arterial pressure, partial arterial oxygen pressure, forced expiratory volume and forced vital capacity (5). Plasma BNP increases in proportion to the extent of RV dysfunction (6) and may have a strong, independent association with increased mortality rates in patients with primary pulmonary hypertension (7). Because decisions on whether to admit patients with COPD or asthma to intensive care depend on clinicians' prognoses (8), we strongly suggest that BNP testing might be helpful for the differential diagnosis of dyspnea and for predicting clinical outcomes. References. 1. Fan E, Needham DM. Deciding who to admit to a critical care unit. BMJ. 2007 Nov 1; [Epub ahead of print]. 2. McCullough PA, Hollander JE, Nowak RM, Storrow AB, Duc P, Omland T, McCord J, Herrmann HC, Steg PG, Westheim A, Knudsen CW, Abraham WT, Lamba S, Wu AH, Perez A, Clopton P, Krishnaswamy P, Kazanegra R, Maisel AS; BNP Multinational Study Investigators. Uncovering heart failure in patients with a history of pulmonary disease: rationale for the early use of B-type natriuretic peptide in the emergency department. Acad Emerg Med. 2003;10:198-204. 3. Davis M, Espiner E, Richards G, Billings J, Town I, Neill A, Drennan C, Richards M, Turner J, Yandle T. Plasma brain natriuretic peptide in assessment of acute dyspnoea. Lancet. 1994;343:440-4. 4. Cabanes L, Richaud-Thiriez B, Fulla Y, Heloire F, Vuillemard C, Weber S, Dusser D. Brain natriuretic peptide blood levels in the differential diagnosis of dyspnea. Chest. 2001;120:2047-50. 5. Bozkanat E, Tozkoparan E, Baysan O, Deniz O, Ciftci F, Yokusoglu M. The significance of elevated brain natriuretic peptide levels in chronic obstructive pulmonary disease. J Int Med Res. 2005;33:537-44. 6. Nagaya N, Nishikimi T, Okano Y, Uematsu M, Satoh T, Kyotani S, Kuribayashi S, Hamada S, Kakishita M, Nakanishi N, Takamiya M, Kunieda T, Matsuo H, Kangawa K. Plasma brain natriuretic peptide levels increase in proportion to the extent of right ventricular dysfunction in pulmonary hypertension. J Am Coll Cardiol. 1998;31:202-8. 7. Nagaya N, Nishikimi T, Uematsu M, Satoh T, Kyotani S, Sakamaki F, Kakishita M, Fukushima K, Okano Y, Nakanishi N, Miyatake K, Kangawa K. Plasma brain natriuretic peptide as a prognostic indicator in patients with primary pulmonary hypertension. Circulation. 2000;102:865-70. 8. Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D, Young D, Rowan K. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study. BMJ 2007 Nov 1; [Epub ahead of print]. Competing interests: None declared
CAOS- grouping COPD and Asthma may underestimate the discrepancy between predicted and actual prognosis for COPD. What about 'COS'? 13 November 2007
Suveer Singh, Consultant in ICU and Respiratory Medicine Chelsea and Westminster Hospital, London, UK SW10 9NH, Daffyd Lloyd, Tasneem Katawala, James Harris, Radha Sabharatnam Send response to journal: Re: CAOS- grouping COPD and Asthma may underestimate the discrepancy between predicted and actual prognosis for COPD. What about 'COS'?	Dear Sirs, We read with interest your online publication regarding the implications of prognostic pessimism in patients with Chronic Obstructive Pulmonary Disease (COPD) and asthma (CAOS)[1]: We have concerns about the interpretation of prognostic estimates by grouping COPD and Asthma together, and that this may underestimate the true discrepancy suggested. These are essentially different diseases, in terms of aetiology, clinical course of exacerbations, and responses to critical care interventions (i.e. ventilatory management). Furthermore, the in-hospital mortalities for those intubated are notably different; ~20-30% for COPD [2,3], and ~10% for Asthma[4]. Both diseases have differing prognostic indicators of outcomes, which we would suggest may have an important influence on ICU clinicians’ judgements as to whether to admit such patients or not. We suggest that patients with severe Asthma are much less likely to be refused admission to ICU and/or intubation, as compared to severe exacerbations of COPD. And perceptions of out of hospital survival for Asthma are likely to be better than for COPD. Therefore, we speculate that the difference between predicted and actuarial survival of the CAOS cohort is likely to have been an underestimate of the prognostic pessimism in a COPD cohort. Indeed, is it not this particular group who we are really concerned may be ‘missing out’ on the services of ICU? We would welcome presentation of the data for COPD alone. 1. Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D, Young D, Rowan K. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study. BMJ. 2007 Nov 1; [Epub ahead of print]. 2. M. G. Seneff; D. P. Wagner; R. P. Wagner; J. E. Zimmerman; W. A. Knaus Hospital and 1-year survival of patients admitted to intensive care units with acute exacerbation of chronic obstructive pulmonary disease JAMA 1995 274: 1852-1857 3. Breen D, Churches T, Hawker F, Torzillo PJ. Acute respiratory failure secondary to chronic obstructive pulmonary disease treated in the intensive care unit: a long term follow up study. Thorax. 2002 Jan;57(1):29-33. 4.Gupta D, Keogh B, Chung KF, Ayres JG, Harrison DA, Goldfrad C, Brady AR, Rowan K. Characteristics and outcome for admissions to adult, general critical care units with acute severe asthma: a secondary analysis of the ICNARC Case Mix Programme Database. Crit Care. 2004 Apr;8(2):R112- 21 Competing interests: None declared
Pessimism; not all bad? 21 November 2007
Olga M Peters-Polman, intensivist university medical center groningen, P.O. 30.001 9700 RB groningen netherlands, Jan G Zijlstra, Jaap E Tulleken, John H Meertens, Jack J Ligtenberg Send response to journal: Re: Pessimism; not all bad?	Wildman et al1 touch on the very important issue of prognostication in critically ill patients. We have some major concerns about the methodology and about the conclusion that unduly pessimism leads to unjustified refusal. What in fact is shown is that doctors, despite their pessimism admit patients to the ICU. This is an implicit sign of their awareness of their limited prognostic capability. An ordeal about the effect of pessimism on unjustified refusal can only be given when also patients that are denied admission because of to low or to high estimated chance of survival are studied. If their mortality is high, did the doctor make the right decision not to admit the patient based on prognostic pessimism? Or is this a self-fulfilling prophecy? Does pessimism of doctors protect patients from refusal because of an overly optimistic prognostic estimation? We also wonder if the intensivist is the right person to predict 180 day mortality. We usually don’t see our patients after they are discharged from the ICU, so there is little insight in the average 180 day mortality in our patient group. In our practise the decision to admit a patient to the ICU is made together with the referring specialist after discussion about the short and long term prognosis. Studying this estimated prognosis would be more realistic. Last, we want to comment on the length of stay of the COPD patients studied. The median length of stay is 16 days. In our ICU unit we have in a comparable patient group a median length of stay of 3 days with a comparable hospital survival and comparable 6 month and 1 year mortality.2 Adjusting targets based on a better prognostication after the patient’s characteristics are better known and the response to therapy can be evaluated compensate for a liberal admission rate. The phenomenon of pessimism of intensivists about prognosis is intriguing and deserves further study. However this is far beyond the scope of this article. The conclusion of this nice observational study must be that doctors are pessimistic in nature, but that they give their patients the benefit of the doubt and do admit them. Prognostication should not be left to intensivists alone. Reference List (1) Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D et al. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study. BMJ 2007. (2) Zijlstra GJ, Zijlstra JG, Postma DS, Wijkstra PJ, Ligtenberg JJM, Tulleken JE et al. Acute respiratory failure in COPD: evaluation of a policy. Intensive Care Med 32[S1], 959. 2006. Ref Type: Abstract Competing interests: None declared
Impact of non-invasive ventilation 30 November 2007
David H Dewar, Specialist Registrar Medway Maritime Hospital, ME7 5NY Send response to journal: Re: Impact of non-invasive ventilation	Wildman, et al. report on the potential pessimism of doctors admiting COPD and asthma patients to intensive care. Since the 18 month study period in 2002/2003, there has been continued evolution in the availability and provision of non-invasive ventilation, in particular Bi- level Positive Airway Pressure(BIPAP), outside of intensive care. The vast majority of acute Trusts now have BIPAP devices readily availible for use in Accident and Emergency, Respiratory wards or Medical High Dependency Units, which were not significantly represented in this study. Accordingly, the vast majority of current COPD patients are not admitted to Intensive Care for respiratory support. This study does not report the proportion of patients who may have received non-invasive ventilation which, in its early development, did neccesitate admission to intensive care in many hospitals. Difficulty weaning severe COPD patients off a ventilator is often the main reason for pessimism and refusal of intensive care admission. I presume that nearly all patients with asthma would be expected to survive their admission to intensive care and should not therefore been included in this cohort. Competing interests: None declared
Different intensivists with different approaches 1 December 2007
M Samer Abdalla, Specialist Registrar in Anaesthesia & ICM Homerton University Hospital, London E9 6SR, UK Send response to journal: Re: Different intensivists with different approaches	I read with great interest the paper published by Wildman et al(1). I would like to make a few comments. The study did not take into account the potential effect of the variation of management among different intensivists on the survival of patients with chronic obstructive pulmonary disease (COPD). I do appreciate that the study covered 92 UK intensive care units (ITUs); however the COPD management is not standarised all over the country. Antibiotic choices, non-invasive versus invasive ventilation, liberal versus restricted fluid therapy, timing of performing tracheostomy, if ever performed, are just a few differences to mention. I think including three respiratory high dependency units in the study, was not necessary as there is clear difference in the level of respiratory support which might have affected the admitting doctor responses to the questionnaire. There was no mention of the associated morbidities influence on the admitting doctor survival estimation. What about the patients who were readmitted to the ITUs? Were they included in the study? Finally, I do not feel comfortable using the word pessimism. If this paper gets misinterpreted by the media and the patients support groups there will be unprecedented pressure on the ITU services and intensivists. I would rather use the term prognosis variabilty. I am wondering why it did take Wildman et al. almost 4 years to get their study published. However, it is an interesting paper which will pave the way for hot debate. watch this space ! 1-Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D et al. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study BMJ, Nov 2007; doi:10.1136/bmj.39371.524271.55 Competing interests: I am an intensivist !
Pessimistic optimism? 4 December 2007
Jeremy Groves, Consultant in Anaesthesia and Intensive Care Chesterfield Royal Hospital, Calow, Chesterfield, S44 5BL Send response to journal: Re: Pessimistic optimism?	I read with interest the article by Wildman et al. There is no question that this article adds significantly to an important debate. However I believe the authors are somewhat disingenuous in the title they have used for the article. The study highlights some helpful prognostic indicators that are related to poor outcome in COPD and asthmatic patients admitted to intensive care (age above 75, low mean arm circumference and being chair or bed bound). This is useful information that will aid the clinical community making decisions that are in the best interest of their patients. What the study does not do is demonstrate that prognostic pessimism is related to refusal to admit patients to intensive care units. The only way to demonstrate that this influenced admissions policy would have been to include patients referred, but refused admission to intensive care units. The conclusion (implication) in the limitations section, that pessimism was likely to have been greater in patients refused admission, than those admitted, is a belief, not a fact. The study does demonstrate that clinicians who believe a patient’s outcome is likely to be poor will still admit them to an intensive care unit (pessimistic optimism?). It is likely to be very reassuring to patients that clinicians act in this fashion. Demonstrating this, and combining it with knowledge of specific and sensitive clinical indicators of outcome, would have been a more productive direction for the CAOS study and a better use of ICNARC’s resources. Competing interests: None declared
Considering factors other than prognosis in admissions to ITU. 5 December 2007
Jane Gibbins, Clinical Research Fellow in Palliative Medicine Department of Palliative Medicine, Bristol Haematology & Oncology Centre, Bristol, BS2 8ED, Colette M Reid, Consultant in Palliative Medicine, Gloucester, Karen Forbes, Professor of Palliative Medicine, Bristol Send response to journal: Re: Considering factors other than prognosis in admissions to ITU.	Editor The study by Wildman et al (1) and the accompanying editorial (2) about prognostic pessimism in patients with COPD, seem to give readers a confusing message about the role of prognostication in the ITU setting. The authors discuss that clinicians are generally pessimistic about the survival prospects of patients with exacerbations of COPD and asthma and this may lead to patients being excluded from the intensive care unit (1). However, this is misleading since despite doctors estimating a shorter than actual prognosis, they still admitted patients to the intensive care setting. Their conclusions can only be supported by finding an accompanying mis-match of prognoses in patients not admitted to the ITUs, yet as the authors concede, a clear limitation of their study is that this evidence is not available. Prognostication in any setting is hard; studies have highlighted that healthcare professionals have difficulty in accurately making prognostic predictions in patients with malignant (3, 4) and non-malignant disease (5, 6). Patients with chronic non-cancer diseases can come close to death on several occasions before they die, making it difficult for healthcare professionals to determine which will be their ‘last episode (6); and hence the time when ITU admission is no longer appropriate. We do not think that focussing solely on survival as an outcome is appropriate for patients in the last months of their life (nearly forty per cent of the study cohort had died at 180 days and 30% of patients died in hospital after their ITU admission) especially since the editorial highlights the fact that patients themselves do not want survival “at any cost”. Although patients and their families have very individual and changing needs with regard to knowing and accepting a prognosis(7), up to one fifth of patients with a non-cancer diagnosis in the last year of their life are reported to suspect that they are dying (8). Only by involving patients and their families in these decisions can we be sure that our risk benefit ratio is truly in the patient’s best interests and does not reflect limited access to critical care facilities. 1.Wildman M, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison, Young D, Rowan K. Implications of prognostic pessimism in patients with COPD or asthma admitted to intensive care in the UK with COPD and asthma outcome study (CAOS): multi-centre observational cohort study. BMJ 2007; 335: 1132-3 2. Fan E, Needham DM. Deciding who to admit to a critical care unit. BMJ 2007; 335:1103-4 3. Christakis N, Lamont E. Extent and determinants of error in doctors' prognoses in terminally ill patients: a prospective cohort study. BMJ 2000; 320:469-473 4.Christakis N, Iwashyna T. Attitude and self-reported practice regarding prognostication in national sample of internists. Arch Intern Med 1998; 158:2389-2395. 5. Gibbs J, McCoy A, Gibbs L, Rogers A, Addington-Hall J. Living with and dying from heart failure: the role of palliative care. Heart 2002; 88:36-39 6. Coventry P, Grande G, Richards D, Todd C. Prediction of appropriate timing of palliative care for older adults with non-malignant life-threatening disease: a systematic review. Age and Ageing 2005; 34:218 -227 7. Higginson I, Priest P, McCarthy M. Are bereaved family members a valid proxy for a patient’s assessment of dying? Soc Sci Med 1994; 38:553- 7 8. Hinton J. How reliable are relatives' reports of terminal illness? Patients and relatives accounts compared. Soc Sci Med 1996; 43:1229-36 Competing interests: None declared
Is it time to reset our perceptions of baseline survival in COPD patients invasively ventilated following the CAOS study? 5 December 2007
Andrew J Burtenshaw, Specialist Registrar Intensive Care Medicine Heartlands Hospital, Birmingham, UK, Chris Gough, Helga Fichter, Neil Crooks Send response to journal: Re: Is it time to reset our perceptions of baseline survival in COPD patients invasively ventilated following the CAOS study?	We would like to commend Drs Wildman et al on their research which has clearly demonstrated a disparity between clinicians’ perceptions of survival and actual survival for COPD patients admitted to the intensive care unit for invasive ventilation. However, we would like to communicate the following thoughts: Firstly we were reassured that the trend of prognostication correlated well. The patients with the worst actual outcome were correctly predicted to fare poorly. The disparity appears to lie not in the strength of correlation but in the perception of the baseline chance of survival. This draws us on to our first point which is that the real question in our minds is what is the minimal percentage chance of survival that warrants admission to the ITU both in terms of patient choice and resource consumption. We believe that the former necessitates frank discussion with the patient in order to facilitate an informed decision, although we are all aware that the clinical scenario in which the patient presents frequently cannot accommodate this. Conversely, the decision to admit a patient to ITU in the context of resource consumption may well be affected if we were to “reset” our perception of the baseline of a survival graph in the light of this study. Our second point is that the mortality against which the reported ITU mortality is to be compared cannot be assumed to be 100%. Advances in NIV equipment and availability in addition to standard medical therapy are believed to have made significant improvements to patient outcome. Competing interests: None declared
ICU for all? 6 December 2007
J R MacDonald, ST 2 ACCS Brighton and Sussex University Hospital, Brighton Send response to journal: Re: ICU for all?	Dear Editor, On reading ‘Implications of prognostic pessimism in patients with COPD etc...’ I noted with interest the findings of Wildman et al. In particular that patients with six month survival predictions of an average of just 3%[1] were admitted to the ICU at all. I am surprised that in a time of such scarcity of ICU facilities that patients with such poor prognoses (however incorrect) were offered ICU support. If ICUs were to routinely admit more than thirty patients for the six month survival of just one there would be considerable pressure on beds, not to mention admitting consultants. References: 1. Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D et al. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study BMJ, Nov 2007; Competing interests: None declared
Physician assessment can be improved but may still be best 12 December 2007
Ian A Rowe, Specialist Registrar in Gastroenterology University Hospital of North Staffodshire, Stoke-on-Trent, ST4 6QG Send response to journal: Re: Physician assessment can be improved but may still be best	Dear Sir – assessment of prognosis of critically ill patients is a core skill for the intensivist. Identifying those patients who will benefit from intensive care whilst not excluding any patients who may also benefit is difficult and several scoring systems have been developed to aid this decision making process. This study from Wildman and co-workers suggests that intesivists are overly pessimistic regarding the prognosis of patients with chronic obstructive pulmonary disease (COPD) and asthma who are admitted to the intensive care unit [1]. In a complementary paper they describe a scoring system which may be used in the assessment of prognosis in patients with exacerbations of COPD and asthma [2]. In patients with chronic liver disease selecting patients for admission to the intensive care unit may be equally challenging. There are many studies looking at outcome in these patients and the development or refinement of prognostic scores [3,4]. Importantly there is a study comparing scoring systems with physician assessment [5]. In this study physician assessment outperformed the well known scoring systems in patients with the worst predicted survival. The major drawback in Wildman’s study is that there are no data from those patients not admitted to the intensive care unit. These data would have given a clearer picture of the prognostic accuracy of the physicians in this setting. Undoubtedly physician assessment of prognosis in COPD and asthma can be improved but it may be the best assessment that is currently available. 1. Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison DA, Young D, Rowan K. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) and asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study. BMJ 2007;335(7630):1132-4. 2. Wildman MJ, Harrison DA, Welch CA, Sanderson C. A new measure of acute physiological derangement for patients with exacerbations of obstructive airways disease: The COPD and Asthma Physiology Score. Respiratory Medicine 2007;101:1994-2002. 3. Wehler M, Kokoska J, Reulbach U, Hahn EG, Strauss R. Short-term prognosis in critically ill patients with cirrhosis assessed by prognostic scoring systems. Hepatology 2001;34:255-61. 4. Cholongitas E, Senzolo M, Patch D, Kwong K, Nikolopoulou V, Leandro G, Shaw S, Burroughs AK. Risk factors, sequential organ failure assessment and model for end-stage liver disease scores for predicting short term mortality in cirrhotic patients admitted to intensive care unit. Aliment Pharmacol Ther 2006;23(7):883-93. 5. Rocker G, Cook D, Sjokvist P, Weaver B, Finfer S, McDonald E, Marshall J, Kirby A, Levy M, Dodek P, Heyland D, Guyatt G; Level of Care Study Investigators; Canadian Critical Care Trials Group. Clinician predictions of intensive care unit mortality. Crit Care Med 2004;32(5):1149-54. Competing interests: None declared
Prognostic pessimism in COPD 17 December 2007
Martin J Wildman, Consultant Chest Physician and Honorary Senior Lecturer , Northern General Hospital Sheffield, S5 7AU Send response to journal: Re: Prognostic pessimism in COPD	Dear Editor, I would like to respond to points made in rapid response to the recent paper describing prognostic pessimism within the CAOS study. (1) It may be helpful to clarify that the study was primarily carried out in order to develop an outcome prediction model to support clinicians in gate keeping decisions for COPD. For this reason any data collected had to be readily available in the period prior to ICU admission in all the hospitals taking part in the study. BNP was not collected as many hospitals do not yet measure it. Similarly accurately distinguishing asthma from COPD in smokers in type II respiratory failure without out patient records can be difficult and for this reason clinicians made their best guess diagnosis. There were only 80 patients out of the whole cohort who were designated as “pure asthmatics”. Whilst the classification of patients into pure COPD, pure asthma or mixed was a helpful variable in the final COAS prediction score the inclusion of asthmatics in the calibration curve did not explain the pessimism. Peters-Polman et al suggest that the intensivist may not be the best person to predict mortality and in the SUPPORT study (2) it was shown that the most accurate prognostication occurred when an outcome prediction model was used alongside clinical decision making. We think this is a strong argument to develop and trial an outcome prediction model in the UK The length of stay quoted by Wildman et al in the introduction to their paper is the hospital length of stay for a historical cohort of 3752 COPD patients admitted to UK ICUs (3) and the median (IQR) ICU length of stay in that study was 4(2-10) days. In the CAOS study the median (IQR) hospital stay was 14(8-27) days (intubated patients 19(10-36)) and the median (IQR) ICU length of stay was 4(2-10) days (intubated patients 8(4- 16). 1. Wildman MJ, Sanderson C, Groves J, Reeves BC, Ayres J, Harrison D et al. Implications of prognostic pessimism in patients with chronic obstructive pulmonary disease (COPD) or asthma admitted to intensive care in the UK within the COPD and asthma outcome study (CAOS): multicentre observational cohort study BMJ, Nov 2007; doi:10.1136/bmj.39371.524271.55 2. Connors AF Jr, Dawson NV, Thomas C, Harrell FE Jr, Desbiens N, Fulkerson WJ, et al. Outcomes following acute exacerbation of severe chronic obstructive lung disease. The SUPPORT investigators (study to understand prognoses and preferences for outcomes and risks of treatments). Am J Respir Crit Care Med 1996;154:959-67 3. Wildman MJ, Harrison DA, Brady ARB, Rowan K. Case mix and outcomes for admissions to UK adult, general critical care units with chronic obstructive pulmonary disease: a secondary analysis of the ICNARC case mix programme database. Critical Care 2005;9(suppl 3):S38-48 Competing interests: I am an author of the pessimism paper.
Should ITU admissions policies be reconsidered? 1 April 2008
Nathaniel M Broughton, Anaesthetic SHO West Suffolk Hospital, IP33 2QZ Send response to journal: Re: Should ITU admissions policies be reconsidered?	Dear Sir, Media reports of ‘prognostic pessimism’ amongst intensivists led me to the paper by Wildman et al. It was reported that patients were being wrongly denied medical treatment. Previous rapid responses have commented upon the questionable design of this study. One further point not yet raised is the distinction between infectious and non-infectious exacerbations of COPD, since potential reversibility might affect the predicted prognosis. Furthermore the authors make no mention of quality of life. The sickest patients had a 64% 180-day mortality – it is therefore likely that the quality of life for the survivors of this cohort was poor. Nonetheless the authors extrapolate this result to ITU admissions policy without further discussion. The question of whether patients with such poor prognoses would wish for invasive ventilation is not discussed. The average ITU stay for ventilated COPD patients is approximately two weeks. If, as the authors desire, more patients were ventilated this would require considerable extra resources. The authors make no attempt to justify this investment for patients with a poor prognosis from chronic disease in comparison to the myriad other medical interventions competing for scarce resources. I believe that this paper neatly demonstrates the reality of prognostic pessimism. However the limitations of this study are such that this evidence should not influence ITU admissions policy without further research. Competing interests: None declared