ed "the routine use of cortico- steroids", without showing that the patient populations or their overall managementwere similar. Fitzgerald and Hargreave.
study involving patient management was retrospective there were no rigid criteria for entry, no standardized treatment protocols and, of course, no control groups. Owing to incomplete objective criteria for severity of illness (or lack of charting of such) we have no clear idea of the grouping of patients according to their presentation (mild, moderate or severe) or of the treatments used for each group. Without this information we cannot assess whether these patients' outcomes were below an acceptable standard and if so why these failures occurred. The authors base their opinion of "suboptimal" management of asthma patients in the emergency department on a relapse rate of 37% and a subsequent admission rate of 13%, without demonstrating better outcomes in a control group following their treatment protocols. They claim that these rates are higher than those in other studies that included "the routine use of corticosteroids", without showing that the patient populations or their overall management were similar. Fitzgerald and Hargreave criticize multiple aspects of the management of these patients, including the histories taken, underuse of spirometry, and inadequate use of anticholinergic and steroid therapy, without linking any of these directly to patient outcome. Their statement that for "all patients with acute asthma" presenting to an emergency department (presumably regardless of severity) "the use of corticosteroids is routinely indicated" is not supported by their findings. They admit that there is controversy regarding the value of spirometry in deciding whether to admit or discharge asthma patients; however, they "continue to recommend it", without adding new, objective evidence to support this practice. Some of the authors' recommendations (the use of spirometry 1186
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contacted at various intervals after the emergency department visit also makes the conclusions suspect. The lack of information from a comparison group makes it difficult to accept as valid the authors' recommendations regarding treatment. Assessment in a "respiratory clinic" is not shown Trevor Gilkinson, MD, FRCPC to be necessary. Department of Emergency Medicine At best this paper presents a Victoria Hospital descriptive study pointing to the London, Ont. need for reassessment of patients Drs. Fitzgerald and Hargreave re- with asthma after emergency detrospectively examined charts partment visits. At worst it is an with the diagnosis of "asthma" unfounded criticism of the quality after the patient's discharge from of care provided in the emergency the emergency department. This department by researchers with method is fraught with recording little knowledge of the reality of error and underrepresentation of care in this setting. Further reclinical findings. Busy emergency search in this area needs to be physicians may provide care first methodologically sound and withand document later. Thus, the out bias to be helpful in manageconclusions regarding asthma as- ment decisions. sessment with this technique are Brian Rowe, MD, CCFP (EM) highly questionable. Gajdowski, MD The authors' insistence on Richard Michael Shuster, MD, FRCPC, DABEM documentation of pulsus paradox- Stephen Lloyd, MD, CCFP (EM), us and on spirometry reflects their DABEM personal preferences, not the view Chedoke-McMaster Hospitals supported by current emergency Hamilton, Ont. medicine research.' The validity of spirometry in the patient with References acute asthma depends on the pa- 1. Worthington JR, Ahuja J: The value of tient's ability to comprehend the pulmonary function tests in the management of acute asthma. Can Med instructions and then comply with 1989; 140: 153-156 them. The reproducibility of the 2. .4ssocJ Feinstein AR, Josephy BR, Wells CK: results with hand-held equipment Scientific and clinical problems in inin this kind of patient in an emerdexes of functional disability. Ann Intern i Med 1986: 105: 413-420 gency department is unproven and questionable. Innuendo regarding the choice of a nebulizer [Drs. Fitzgerald and Hargreave reover a metered-dose inhaler is un- spond.justified by any scientific evidence that one is more efficacious than Our study was an audit with the the other. objective of assessing the current The main weaknesses of this emergency management of asthma study are the inappropriate out- in our hospital. The assessment of come assessment and the lack of a investigation and treatment in the comparison group. Despite abun- emergency department had to be dant measurement tools in the retrospective, but the outcomes field of disability research2 the were assessed prospectively. authors selected a simple, poorly The outcomes of treatment described outcome that provides were poor. Apart from the relapse an assessment that is less than and admission rates cited by Dr. reliable or valid. The fact that Gilkinson, which are significant, only 72% of the patients were we also demonstrated that 2 for all patients and more aggressive use of steroids) have support from existing literature for certain patient populations. From the study presented by the authors, however, we have no way of knowing if their conclusions are valid.
weeks after the visit almost two thirds of the patients still had uncontrolled asthma, as indicated by persistence of cough, sputum or nocturnal waking with wheeze. The relapse rate was similar to that for the patients in the trial by Littenberg and Gluck' who were treated with placebo (rather than corticosteroid) and whose airflow obstruction (mean forced expiratory volume in 1 second [FEVY] 40% of predicted) was similar to that of the patients who underwent spirometry in our study. It therefore seems reasonable to assume that relapses and symptoms would have been less in our study had more corticosteroid been used. Dr. Rowe and colleagues make an issue of the adverse clinical setting of the emergency department. Good treatment is not determined by this but, rather, by the needs of the patient. There are at least two absolute requirements for patients seen in the emergency department for asthma: to measure the severity of the airflow obstruction and to regularly treat with corticosteroid. The severity of airflow obstruction is the primary cause of concern and the primary outcome of treatment on which a rational decision about admission or discharge can be made. It cannot be determined without measurements: many patients have a poor perception of the severity,2 physicians are not good at assessing severity without measurements,3 and physical examination is particularly unrewarding.4 Either the FEV, or the peak flow rate can be measured; both measurements are practical and simple in the emergency department. To suggest that they are "unproven and questionable" is not supported by the literature.' Corticosteroid treatment is indicated because most exacerbations of asthma are associated with exacerbation of the cellular phase of airway inflammation.
The benefit of corticosteroid treatment has been convincingly documented. We found Rowe and colleagues' criticism of our use of symptoms and spirometry as outcome measures intriguing and wonder how they assess patients with asthma if these are not used? We regret that they consider as "innuendo" a statement indicating that metered-dose inhaler therapy is equipotent to wet nebulization therapy, which is well referenced in our article. The recommendation that patients seen in the emergency department should be referred to a respirologist (or a specialist in asthma) is based on the observation that these patients are more likely to die from future severe attacks and that such attacks should be preventable. At present the respirologist or specialist is best able to undertake preventive care. Our study was not a prospective trial of different treatments. However, our observations, and those of Canny and coworkers,6 have emphasized the need for such studies, partly to persuade the sceptics and partly to investigate optimum treatment. In the meantime, recommendations based on current knowledge that are not dissimilar to those discussed in our article have been developed at an international
3. Shim CS, Williams MH: Evaluation of the severity of asthma: patients versus physicians. Am J Med 1980; 68: 11-13 4. Godfrey S, Edwards RHT, Campbell EMJ: Repeatability of physical signs in airway obstruction. Thorax 1969; 24: 4-9 5. Nowak RN, Gordow KR, Wroblewski DA et al: Spirometric evaluation of acute bronchial asthma. JACEP 1979; 8: 9-12 6. Canny GJ, Reisman J, Healy R et al: Acute asthma: observations regarding the management of a pediatric emergency room. Pediatrics 1989; 83: 507512 7. Hargreave FE, Dolovich J, Newhouse MT et al: The assessment and treatment of asthma: a conference report. J Allergy Clin Immunol (in press)
Dystocia and cesarean section
T n he article "Diagnosis of dystocia and management with cesarean section among primiparous women in Ottawa-Carleton" (Can Med Assoc J 1990; 142: 459-463), by Dr. Paula J. Stewart and colleagues, deals with an important area, and we believe that the authors have contributed to the evidence that an appreciable proportion of cesarean sections could be avoided. However, the article presents an opportunity to point out a methodologic misconception that we commonly encounter. The authors state that because their workshop.7 study "included all women who J. Mark Fitzgerald, MB, FRCPC gave birth during 1984, not just a Department of Medicine sample, inferential tests . . . were University of British Columbia not necessary". The misconcepVancouver, BC is that if an investigator tion Frederick E. Hargreave, MD, FRCPC studies all eligible subjects within Department of Medicine McMaster University a defined region and time period Hamilton, Ont. - that is, a census rather than a sample of eligible subjects - then References consideration of sampling error and related statistical testing are 1. Littenberg B, Gluck EH: A controlled trial of methylprednisolone in the emer- not necessary. There are problems with the gency treatment of acute asthma. N Engi J Med 1986; 314: 150-152 proposition that because all 2. Burdon JGW, Juniper EF, Killian KJ et women giving birth in four study al: The perception of breathlessness in included asthma. Am Rev Respir Dis 1982; 126: hospitals in 1984 were sampling error is not an issue. We 825-828 CAN MED ASSOC J 1990; 142 (11)
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