Effect of a clinical protocol on the management of acute asthma in the emergency room of a university hospital

Abstracts

INTRODUÇÃO: Existe grande variabilidade de prática clínica no tratamento da asma aguda na sala de emergência, o que interfere na qualidade de atendimento. OBJETIVO: Avaliar o efeito da implantação de um protocolo assistencial de asma aguda no Serviço de Emergência do Hospital de Clínicas de Porto Alegre. MÉTODO: Estudo transversal, antes e após a implantação do protocolo assistencial de asma aguda no setor de adultos (idade > 12 anos) do referido serviço, avaliando o efeito das recomendações sobre a avaliação objetiva da gravidade, solicitações de exames, uso de terapêutica recomendada, uso de terapêutica não-recomendada e desfechos da crise. RESULTADOS: Na fase pré-implantação, foram estudados 108 pacientes e, na fase pós-implantação, 96 pacientes. Houve aumento na utilização da oximetria de pulso (de 8% para 77%, p < 0,001) e do pico de fluxo expiratório (de 5% para 21%, p < 0,001). Ocorreu aumento na utilização de recursos radiológicos (de 33% para 66%, p < 0,001) e de hemograma (de 11% para 25%, p = 0,016). Houve aumento no número de pacientes que receberam as três nebulizações preconizadas para a primeira hora de tratamento (de 22% para 36%, p=0,04). Embora a utilização geral de corticóide não se tenha modificado, houve aumento no uso de corticóide oral (de 8,3% para 28%, p < 0,001). Não houve alteração significativa na utilização de medidas terapêuticas não-preconizadas, no tempo de permanência na sala de emergência, nem nas taxas de internações e de altas. CONCLUSÃO: A aplicação do protocolo assistencial de asma aguda na sala de emergência obteve efeito positivo, com maior utilização de medidas objetivas na avaliação da gravidade e de medidas terapêuticas recomendadas, porém não teve repercussão sobre tratamento e desfechos.

Protocolos clínicos; Asma; Medicina de emergência

ORIGINAL ARTICLE

Effect of a clinical protocol on the management of acute asthma in the emergency room of a university hospital^*

Pérsio Mariano da Rocha; Andréia Kist Fernandes; Fernando Nogueira; Deise Marcela Piovesan; Suzie Kang; Eduardo Franciscatto; Thaís Millan; Cristine Hoffmann; Carísi Anne Polanczyk; Sérgio Saldanha Menna Barreto ^(TE-SBPT); Paulo de Tarso Roth Dalcin^(TE-SBPT)

^{Correspondence}

ABSTRACT

BACKGROUND: There is a wide variability in clinical practice for treating acute asthma (AA) in the emergency room (ER) interfering in the quality of management.

OBJECTIVE: To evaluate the impact of a clinical protocol for care of acute asthma in the ER of the Hospital de Clínicas de Porto Alegre.

METHOD: In this hospital a cross-sectional study was conducted before and after implementation of the protocol, of consecutive patients presenting with acute asthma in the adult ER (age > 12 years). The intention was to measure the effect of recommendations on the objective assessment of severity, utilization of diagnostic tools, proposed therapy, not recommended therapy and on the outcomes.

RESULTS: The pre-protocol group comprised 108 patients and the protocol group comprised 96 patients. There was a significant increase in the use of pulse oximetry (8% to 77%, p<0.001) and PEFR (5% to 21%, p<0.001). There was an increase in the utilization of radiology (33% to 66%, p<0.001) and in that of blood tests (11% to 25%, p=0.016). There was also an increase in the number of patients receiving the three recommended nebulizations in the first hour (22% to 36%, p=0.04). Although the overall use of corticosteroids did not change, there was a significant increase in the use of oral steroids (8% to 28%, p<0.001). There was no significant difference in the not recommended therapy, time of stay and outcomes.

CONCLUSION: The acute asthma clinical protocol used in the ER was associated to a positive effect on the objective assessment of severity of asthma and on the use of the recommended therapy. No other significant influence on the treatment or on the outcome was perceived.

Key words: Clinical protocols. Asthma. Emergency medicine.

Abbreviations used in this paper:

HCPA – Hospital de Clínicas de Porto Alegre

PEF – Peak expiratory flow

SpO₂ – Arterial oxygen saturation by pulse oximetry

FEV₁ – Forced expiratory volume in one second

ICU – Intensive care unit

Introduction

The prevalence of bronchial asthma ranges from 5% to 10%.⁽¹⁾ Asthma attacks are very common medical emergencies.⁽²⁾ Asthmatic patients presenting acute bronchoconstriction represent from 1% to 5% of emergency room cases in the USA.^(2,3) In Brazilian emergency rooms, acute asthma is responsible for approximately 12% of adult cases and 16% of pediatric cases.⁽⁴⁾

Over the past few years, an increase in asthma-related morbidity and mortality has been reported, despite the concurrent expansion of knowledge regarding the physiopathology and treatment of the disease. Although this contradiction has not been fully explained, one of the reasons for the disheartening statistical data is the fact that these advances have not been adequately divulged.⁽⁵⁾

In order to address this problem, evidence-based guidelines for the diagnosis, evaluation, and treatment of bronchial asthma have been developed.^(1,6-8) Nevertheless, various studies have shown considerable variability in standards of clinical practice employed by physicians who treat asthmatic patients, and this inconsistency interferes with the quality of care.^(9-13) This has motivated institutions to develop clinical protocols that standardize and systematize medical practices, reducing variation, eliminating unnecessary examinations and services, and improving overall patient care.⁽¹⁴⁾

Emergency services play a central role in the treatment of severe acute asthma. Fundamental steps taken during initial emergency room treatment may determine the outcome of the disease.⁽¹⁵⁾

The objective of this study was to evaluate the effect of implementing a clinical protocol for the management of acute asthma in the adult sector of the Serviço de Emergência do Hospital de Clínicas de Porto Alegre (HCPA) emergency room.

Methods

Prior to and following the implementation of a clinical protocol for the management of acute asthma in the adult sector of the HCPA emergency room, a cross-sectional study was conducted. This was done in order to evaluate the effect of the protocol recommendations on objective assessment of severity, use of diagnostic tools, therapies recommended and not recommended, and outcomes.

The Research Ethics Committee of the HCPA approved the study. The authors have signed an agreement regarding the use of data collected during the study.

The study comprised two consecutive samples of adult (age > 12 years) acute asthma patients who were treated in the HCPA emergency room between January 1, 2001 and March 31, 2001 and between January 1, 2002 and March 31, 2002. Patients were selected according to the following inclusion criteria: previously diagnosed with asthma, as defined by the Third Brazilian Consensus on Asthma Management⁽²⁾; presenting symptoms of the acute form of the disease (dyspnea, wheezing or cough); age 12 or older. Patients with chronic respiratory disease or cardiac insufficiency, as well as those whose records were considered insufficiently complete for the purposes of the study, were excluded.

During 2000 and 2001, the clinical protocol for acute asthma in adults was developed by a multi-disciplinary group within the HCPA and conforms to institutional policy on clinical protocols for the most frequently encountered clinical situations. The protocol was designed around evidence-based recommendations for acute asthma management in patients older than 12 and is aimed at improving the quality of service for those patients and at optimizing the expenditure of health resources. The protocol provides guidelines for diagnosis, assessment of severity, treatment, nursing care and analysis of complications, as well as criteria for hospital admission and discharge.

The initial phase of the study involved pre-implementation evaluation of emergency room practices and outcomes. The second phase of the study was carried out only after the protocol had been fully integrated into emergency room practice. During both phases, data from outpatient medical records were transferred to a specific questionnaire for data compilation. Relevant data included patient identification, type of assistance provided during emergency treatment (including diagnostic tools employed and therapeutic measures taken), duration of stay and outcome of the asthma attack.

Over the months of October and December of 2001, emergency room medical and nursing staff attended meetings in which information regarding the new protocol was disseminated and discussed. The hospital administration was involved in making the equipment used for determining peak expiratory flow (PEF), as well as the accompanying disposable mouthpieces, available. Multiple copies of the clinical protocol were distributed in the sector, and it was recommended that they be used as a reference when treating cases of acute asthma. Nursing assistants and technicians were invited to training meetings in which they were trained in how to measure PEF and arterial oxygen saturation by pulse oximetry (SpO₂). Correspondence was sent to all emergency room medical and nursing personnel, calling their attention to the implementation of the new protocol. As a reminder of the change in practice, posters were affixed to the walls of the emergency room staff lounge.

Data were entered into a Microsoft Excel^® (version 2000) database and were processed and analyzed with the help of the Statistical Package for the Social Sciences (SPSS) software, version 10.0.

A comparative analysis was performed during the two phases of the study. Student’s t-test for independent samples was used for the analysis of continuous variables with a normal distribution. Mann-Whitney U test was used for the analysis of continuous variables without normal distribution. For analysis of categorical variables, we used the chi-square test and, when necessary, Yates’ correction or Fisher’s exact test. Statistical significance was set at p < 0.05 and the 95% confidence intervals were determined.

Results

During the first phase, prior to the implementation of the protocol, 141 adult patients diagnosed with acute asthma presented to the emergency room. Of these 141 patients, 33 were excluded from the study: 26 because they also presented chronic lung disease, 3 because they presented congestive cardiac insufficiency, and 4 because their charts were incomplete. Therefore, 108 patients were included in this phase of the study. Of the 108, 88 (81.5%) were female and 20 (18.5%) were male. The mean age was 42 ± 19.1.

During the post-implementation phase of the study, 132 patients were diagnosed with acute asthma. Of these, 24 patients were excluded from the study because they also presented chronic lung disease, 1 patient because of congestive cardiac insufficiency, and 11 patients because of incomplete data in the records. Therefore, in this phase of the study, 96 patients were included. Of the 96, 61 (63.5%) were female and 35 (36.5%) were male. The mean age was 45.5 ± 18.3.

Statistical analysis of demographics (gender, race and age) and of objective evaluations of severity, as well as of the diagnostic tools employed, is shown in Table 1.

There was statistically significant demographic difference in gender between the two phases of the study (p = 0.006). There were more male patients during the post-implementation phase of the clinical protocol than during the pre-implementation phase. There was also a statistically significant demographic difference in race (p < 0.001), since there were more patients of African descent in the post-implementation phase.

As for objective evaluation of attack severity, there was a statistically significant increase in the use of both PEF (p < 0.001) and pulse oximetry (p < 0.001) between the pre- and post-implementation phases.

In the analysis of the diagnostic tools employed, we found a statistically significant increase in the use of radiological exams (p < 0.001) and blood tests (p = 0.016) between the pre- and post-implementation phases. There were no significant differences in the use of the other diagnostic tools.

Table 2 shows the statistical comparison of the two phases of the study regarding the use of therapeutic modalities. There were no statistically significant differences in the use of oxygen therapy, short-acting b₂-agonists, ipratropium bromide or systemic corticosteroid therapy.

In evaluating the use of short-acting b₂-agonists administered by nebulizer, we found that there was a discrete post-implementation increase in the number of administrations within the first hour of emergency room treatment. However, this increase was not statistically significant (p = 0.053). During the pre-implementation stage, the frequency of administration during the first hour of treatment was 1.51 ± 0.84. After implementation of the protocol, this increased to 1.76 ± 0.96. There was, however, a significant increase (p = 0.04) in the number of patients given the three administrations recommended by the protocol (22.2% during the pre-implementation phase and 36.5% after implementation).

From the pre- to the post-implementation phase, there was a significant increase in oral over intravenous administration of systemic corticosteroid therapy (p < 0.001).

There was no significant difference between the two study phases in the use of therapies that are not recommended.

Duration of stay in the emergency room during the pre-implementation phase was 12.4 ± 17 hours, compared with 13.5 ± 13.1 hours during the post-implementation phase (p = 0.876).

For a number of the parameters evaluated, pre- vs. post-implementation differences were not statistically significant (p = 0.436, collectively). These parameters included discharge from the emergency room (pre-: 93.5%; post-: 95.8%), hospitalization (pre-: 3.7%; post-: 4.2%), intensive care unit (ICU) admission (pre-: 0.9%; post-: 0%) and death (pre-: 1.9%; post-: 0%).

Discussion

The present study evaluated the effect of implementing a clinical protocol for the management of acute asthma in adults treated in a university hospital emergency room. In order to identify the effect of the recommendations for the clinical management of acute asthma, the studied variableswere classified in accordance with the Third Brazilian Consensus for Asthma Management.⁽²⁾

There were statistically significant demographic differences in gender (p = 0.006) and race (p < 0.001) between the pre- and post-implementation phases. These differences may have occurred randomly, since the study periods were pre-established and all patients were included sequentially. In all likelihood, these differences did not interfere with the results of the evaluation of the clinical protocol.

There was a significant post-implementation increase in the use of objective measures to evaluate attack severity. For example, PEF was measured in 4.6% of patients prior to implementation of the protocol and in 20.8% after implementation. Oxygen saturation was determined in 8.3% of patients during the pre-implementation phase, compared with 77.1% during the post-implementation phase. However, even after the new clinical protocol had been implemented, the use of oxygen saturation and PEF measurements was less frequent than that recommended in established guidelines.^(1,2,7,8) The limited use of these parameters in the evaluation of attack severity may be attributable to a lack of awareness among health professionals regarding the importance of such measures, combined with the overwhelming volume of work currently confronting health care personnel. Therefore, in order to properly evaluate the severity of an asthma attack during initial diagnosis and evolution, it is important to ensure availability of adequate (PEF and pulse oximetry) equipment, as well as to provide training and continuing education of emergency medical and nursing staff.

Studies in the literature report that measurement of airflow limitation through spirometric determination of forced expiratory flow in one second (FEV₁) and PEF determination using a PEF meter, as well as measurement of SpO₂, yield initial objective data on attack severity and aid in quantifying treatment response and in making decisions about hospitalization.^(16-18) The objective determination of severity is essential because signs and symptoms that indicate the severity of an asthma attack disappear after treatment effects even a small increase in FEV₁, and patients may be considered clinically recovered while still suffering from severely limited airflow.^(16,18)

In our study, the use of radiological exams and blood tests was actually greater during the post-implementation phase, indicating that the recommendations suggested by the protocol were not followed in relation to these parameters. In our hospital, the codification used in the various clinical protocols employs the symbol for mandatory procedures and the symbol for optional procedures. Clinical examination and medical history appeared on patient charts marked as mandatory, whereas chest and sinus X-rays, blood tests, biochemical tests, and arterial blood gas analysis were marked as optional. Although, in the written version of the protocol, it was not explicitly stated that these procedures should only when there is clinical suspicion of complications, this had been explained to those who attended the related seminars, training sessions, and clinical discussions. It is possible that this codification might have led the doctors in the emergency department to mistakenly request a greater number of radiological exams and blood tests. This point should be modified in a future version of the protocol.

Therapeutic measures recommended for the management of acute asthma in emergency rooms include the use of oxygen therapy, inhaled short-acting b₂-adrenergic bronchodilators, ipratropium bromide and systemic corticosteroids. These therapeutic measures are based on evidence and recommended by the established guidelines.^(1,2,7,8) In general, the appropriate use of these measures is an indication of the quality of care provided by a specific institution.⁽¹⁾ There were no significant differences between overall pre- and post-implementation use of oxygen therapy, short-acting b₂-agonists, ipratropium bromide or systemic corticosteroids. In general terms, the indication of these therapeutic measures was in accordance with clinical recommendations.^(1,2,8) In a more detailed analysis, we can observe a slight increase in the frequency of nebulizer use, although the increase was not statistically significant (p = 0.053). There was also an increase in the number of patients who were given the recommended 3 nebulizer administrations during the first hour of treatment (p = 0.04). However, the frequency of administration was still lower than that recommended in the established guidelines, even after implementation of the new protocol. It is important to highlight that, at the time of this study, the only system for administration of inhaled bronchodilators available in the HCPA emergency room was continuous nebulization. There was a significant post-implementation increase in the use of oral over intravenous administration of corticosteroids (p < 0.01).

Therapeutic measures based on insufficient or contradictory evidence were considered “non-approved therapeutic procedures”. Although these procedures are not recommended in routine practice, they present options for the management of asthma attacks that either do not respond to or worsen with the recommended therapy. Although they are not contraindicated, the excessive use of these procedures constitutes poor quality of care in the management of acute asthma. The use of such procedures was minimal during the pre-implementation phase of the study, and no significant differences were detected during the post-implementation phase.

Although data were collected during the summer, it is unlikely that this factor affected the results since the medical team remains virtually the same throughout the year. The team is composed of permanent personnel (hired physicians) who always work in the emergency room and temporary personnel (residents and interns) who are on monthly rotation in the emergency room. Vacations for permanent personnel are covered by the temporary staff.

We must highlight the fact that emergency room operations in our hospital are divided between the pediatric and adult sectors, with a cutoff age of 12 for the use of pediatric services, and that the present study involved only the adult sector.

Due to the increasing use of clinical guidelines and protocols, one topic that must be investigated is the difference between measures recommended (in guidelines and protocols) and their effective application. Various studies concentrate on the analysis of the real application or adherence to clinical protocols by the medical staff of health care institutions.^{(9,10,12,13,19-21)} Among the reasons for medical staff non-adherence to a specific guideline are lack of detailed knowledge of the protocol, disagreement with the recommendations or simply a lack of awareness of the protocol.^(19,22) Other factors that influence adherence to a protocol are lack of personal motivation, limited time or resources for application of the protocol and, at times, patient refusal to be submitted to certain diagnostic and therapeutic procedures.⁽¹⁹⁾ It is fundamental that, prior to the implementation of any clinical protocol, adequate training is given in order to familiarize and motivate the staff regarding the new protocol.⁽²²⁾

In emergency rooms, especially those in university hospitals with medical residence programs, in which personnel are on monthly rotations, the chance that some members of the medical staff will not follow guidelines and protocols is greater.⁽²³⁾ In an academic setting, medical students should be made aware of clinical protocols so that they can deliver more standardized and higher-quality care.⁽²⁴⁾

It is important to consider the real advantages of implementing a clinical protocol in the emergency room because of the differences between recommendations and practical application. It is also important to determine to what extent knowledge of and adherence to the recommendations given in guidelines or protocols have changed medical staff practices and positively affected outcomes.⁽²⁵⁾ In light of this, specific studies should be conducted in order to evaluate the effect that implementation of given clinical protocols has on patients treated in emergency rooms.

In conclusion, the implementation of the clinical protocol for acute asthma in the adult sector of the HCPA emergency room had a positive effect on patients with asthma attacks. Determination of PEF and the use of pulse oximetry became more frequent, the recommended 3 administrations of bronchodilator nebulization during the first hour of treatment were given more often, and oral corticosteroids were administered in more cases. In addition, the use of diagnostic procedures (radiological exams and blood tests) increased. However, there were no differences in duration of emergency treatment, number of hospital admissions, or number of discharges from the emergency department.

Acknowledgments

We thank Vânia Naomi Hirakata and Professor Mário Bernardes Wagner for the statistical analysis. We also thank Professor Laura Maria Brenner Ceia Ramos Mariano da Rocha for reviewing the manuscript, and the medical, nursing, and administrative staff of the HCPA Serviço de Emergência for their collaboration in the study.

References

Submitted: 8 October 2003.

Accepted, after revision: 20 November 2003.

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*

Study carried out at the Faculdade de Medicina da Universidade Federal do Rio Grande do Sul.

Publication Dates

• Publication in this collection
  08 June 2004
• Date of issue
  Apr 2004

History

• Received
  08 Oct 2003
• Accepted
  20 Nov 2003