PATIENTS‟ VITAL SIGNS AND THE LENGTH OF TIME BETWEEN THE MONITORING OF VITAL SIGNS DURING TIMES OF EMERGENCY DEPARTMENT CROWDING By KIMBERLY D. JOHNSON Submitted in partial fulfillment of the requirements For the degree of Doctor of Philosophy Dissertation Advisor: Dr Chris Winkelman Frances Payne Bolton School of Nursing CASE WESTERN RESERVE UNIVERSITY May, 2011 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of ______Kimberly D. Johnson _______________________________ candidate for the ______PhD_________________________degree *. (signed)_____Chris Winkelman_____________________________ (chair of the committee) ________Mary A. Dolansky___________________________ ________Vicken Y. Totten MD________________________ ________Christopher J. Burant________________________ ________________________________________________ ________________________________________________ (date) ______December 17, 2010_________________ *We also certify that written approval has been obtained for any proprietary material contained therein. DEDICATION I dedicate my dissertation to my wonderful family without whom I could not have completed this project. To Erik, my supportive and understanding husband, thank you for not letting me quit and for your endless encouragement and patience. Richard Samuel, you‟re the best project I ever completed. When I started this program I never dreamt that I would finish it with a degree and a child. God is good. My parents, Donald and Shirley Blasko, I thank you for inspiring me to become a nurse as well as emphasizing the importance of education, hard work and setting priorities. To my „spare‟ parents, Richard and Susan Johnson, thanks for your love, support and free babysitting service. iv Table of Contents List of Tables viii List of Figures x Acknowledgements xi Abstract xii Chapter One Introduction 1 Purpose of the study 3 Background and Significance 3 Effect of ED Crowding on Quality Care Indicators 5 Cost of ED Crowding 6 The Role of the Emergency Nurse 8 Problem statement 8 Theoretical Framework 9 Vital Signs 22 Research questions 28 Significance of study 28 Assumptions of the study 31 Definition of Terms 31 Chapter Two Literature Review 36 ED Crowding 36 ED Crowding and Adverse Outcomes 41 v Vital Signs 53 Conclusion 60 Literature Review Chart 62 Chapter Three Methods 72 Setting 73 Sample 73 Data Collection /Study Procedures 77 Chart Extraction 79 Instrumentation 80 ED Crowding 80 Demographic Variables 82 Arrival Information 82 Patient Health Status 83 Triage Category 84 Vital Signs 86 Nurses‟ Response to Abnormal Vital Signs 89 Additional Contextual Factors 89 Human Subjects 91 Data Protection 92 Data Management 93 Data Analysis 93 Chapter 4 vi Results 98 Sample 98 Vital signs 101 Missing values 103 Analysis of Research questions 103 Research Question 1 Results 103 Research Question 2 Results 105 Research Question 3 Results 117 Research Question 4 Results 120 CHAPTER 5 Discussion 122 Setting and Sample 122 Findings 125 Research Question 1 Findings 126 Research Question 2 Findings 128 Research Question 3 Findings 133 Research Question 4 Findings 135 Power 136 Theoretical Framework 137 Strengths and Limitations 140 Implications for Practice 144 Future Research 145 Conclusion 147 vii Appendix 1 ESI Triage Algorithm 151 Appendix 2 Results of testing the primary and secondary assumption of regression for Research Question 1 152 Appendix 3 Results of primary and secondary assumptions of regression for Research Question 2 153 Appendix 4 Transformation for Research Question 2: Linearity of Age variable 158 Appendix 5 Results of Transformation to Improve Linearity of OTC Variable for Research Question 2 159 Appendix 6 Results of Transformation to Improve Linearity of Med Route Variable for Research Question 2 160 Appendix 7 PI designed data collection tool_________________________161 References 164 viii List of Tables 1. Variables representing Concepts in Hypothesized Model 20 2. Literature review tables 2-1 Studies that examined the association between ED crowding and adverse outcomes 62 2-2 Studies that examined Quality of care in ED 68 2-3 Studies that look at the assessment of vital signs/physiological changes as prediction of adverse outcomes 70 3. MEWS calculation 87 4. List of data points collected 90 5. Summary of Vital Signs during all 3 time points collected 102 6. Summary of Factors Theorized to Affect the Length of Time Between Vital Signs 103 7. Summary of Correlation Analysis for EDWIN score on Minutes Between Vital Signs (N=192) 104 8. Descriptive Statistics for Variables Included in Research Question 2 106 9. Analysis of Collinearity and Correlations to the Length of Time (min) between Vital Sign Recordings 110 10. Explained variance for the Length of Time between Vital Sign Recordings 110 11. Results of Goodness of Fit Indices with Removal of Nonsignificant paths 112 ix 12. Summary of Significant Regression weights for Endogenous Variables 116 13. Summary of Covariances 116 14. Descriptive stats for Research Question 3 variables 119 15. Correlations between the Time from Abnormal vital sign Acknowledgement to Reaction time 119 16. Descriptive statistics for Research Question 4 121 17. Results of Regressions of EDWIN score on Vital signs (MEWS) 121 18. The Effect of Crowding on changes in Individual Vital Signs 121 x List of Figures 1. Asplin et al (2003) Model of ED Crowding 10 2. Figure 2. Modification to Asplin model 15 3. Donabedian Structure-Process-Outcome 16 4. Modified Model of ED Crowding 19 5. Tested portion on of modified model of ED crowding 19 6. Hypothesized relationships among study variables 21 7. Substruction of Theoretical Model 22 8. Original Hypothetical Model 111 9. Final Model with Standardized Regression Weights 114 10. The modified model of ED crowding 138 xi ACKNOWLEDGEMENTS I would like to thank all of the people that made this dissertation possible. I am incredibly grateful for the many colleagues and friends that have provided support, clarification, inspiration and guidance to me during this endeavor. First, I thank my advisor, Chris Winkelman for all of your guidance, encouragement and patience. I have learned more from you than you will ever know. Thank you for entertaining all of my many, many research ideas and helping me narrow those ideas into something manageable. I am inspired by your excitement and dedication to research. I would also like to thank Chris Burant for making statistics fun and understandable. Next, I thank Mary Dolansky. Your passion for quality improvement is infectious. Thank you for providing me with direction in the development of my conceptual model. I would like to thank Dr. Vicken Totten for providing a unique perspective that added depth and meaning to this project. I would like to say a special thank you to Amy Bieda and Jean Chiang for providing much laughter and a reprieve from my long commute. I will forever be grateful for your room and board and friendship. Finally, I acknowledge the staff in the Medical Records Department at UHCMC who was incredibly helpful and efficient. xii Patients‟ Vital Signs and the Length of Time between the Monitoring of Vital Signs During Times of Emergency Department Crowding Abstract By KIMBERLY D. JOHNSON The purpose of this study was to examine patients‟ vital signs and what factors influence the length of time between vital sign recordings during various levels of ED crowding. Secondary purposes were to explore the nurse's response when vital signs were abnormal and to investigate the effect of ED crowding on the occurrence of abnormal vital signs. Vital signs are an integral component of the nursing assessment and often used as a decision-making tool. There is limited information about discernment of clues (i.e. vital sign abnormalities) that precede catastrophic outcomes. It is not known if crowding affects vigilance and reporting/communicating in the presence of clues. Current research does not provide information of the effect that ED crowding on the quality of care provided to ED patients by nurses. A conceptual model was developed for this study by merging Asplin‟s Model of ED Crowding and Donabedian‟s Structure-Process- Outcome Model. A descriptive, retrospective chart review was performed of 202 randomly selected adult ED patients' charts using a strategic sampling plan to capture a variety of ED occupancy scenarios at an urban, teaching hospital. Data was analyzed using multiple regression, correlation and Structural Equation Modeling. The results of this study demonstrated that: (a) as crowding increased, xiii the time between vital signs increased significantly but the clinical importance of this finding needs further investigation, (b) several factors contributed to the length of time between vital sign recordings: length of stay, triage category and patients arriving by private car had the greatest predictive value, (c) reactions to abnormal vital signs were not commonly documented by nursing in the handwritten records used for this project (d) ED crowding did not have an effect on the composite vital signs of patients. Results from this study may contribute to establishing a standard of care related to frequency of vital signs monitoring. Future study should focus on determining if frequency of vital signs surveillance contributes to high quality care. Findings also provide direction for future research linking quality of care to missing vital signs or inadequate monitoring and ED team response to abnormal vital signs. 1 Chapter One