Effect of Interhospital ICU Relocation on Patient Physiology and Clinical Outcomes

Abstract

Relocation of large numbers of critically ill patients between hospitals is sometimes necessary and the risks associated with relocation may be high. In the setting of adherence to an interhospital intensive care unit (ICU) relocation protocol, we aimed to determine whether the interhospital relocation of all ICU patients in a single day is associated with changes in vital signs, device removal, and worse clinical outcomes. We conducted a prospective, observational, cohort study of all critically ill adults admitted to a tertiary medical center’s ICUs on the day of a planned hospital relocation and exposed to interhospital ICU relocation compared with unexposed critically ill adults. Changes in vital signs were evaluated by the before-and-after interhospital relocation measurement of vital signs, and clinical outcomes were collected for all patients. A total of 699 patients were admitted to the ICU during the observation period, 24 of whom were exposed to interhospital ICU relocation on a single day. The median interhospital transport duration was 28 minutes (interquartile range: 24-35) and 29% of patients were receiving invasive mechanical ventilation. Patients exposed to interhospital ICU relocation had no significant change in any vital sign measurement and no devices were unintentionally removed. Inhospital mortality was similar (8.3%) to patients not exposed to interhospital ICU relocation (9.2%, P > .99). In the setting of adherence to an ICU relocation protocol, the interhospital ICU relocation of all critically ill adults during a single day is not associated with changes in vital signs, device removal, or worse clinical outcomes.

Keywords

ICU organization ICU staffing interhospital transfer

Introduction

Relocation of large numbers of critically ill patients between hospitals is sometimes necessary during times of significant infrastructure change and natural disasters; however, there is limited literature describing the risks to patients during this process.^1

–4 The processes of care used to perform interhospital intensive care unit (ICU) relocation (IHR) and the potential detrimental effects of IHR of all ICU patients in a single day have not been described.

The transport of a single critically ill adult is associated with a number of potentially harmful physiologic changes and device dislodgements,^5
–7 including increased partial pressure of carbon dioxide, increased heart rate, and decreased pH and blood pressure.^6,7 Approximately one-third of critically ill adults undergoing transport experience device detachment, dislodgement, or malfunction most commonly during transport or on arrival at the destination⁵ and patients receiving invasive mechanical ventilation may be a population at higher risk of the above complications.⁸ In response to these known complications of transport, specialist retrieval teams,⁷ consensus statements,⁹ and guidelines¹⁰ have been created to reduce the complications of transport of critically ill patients. However, these recommendations are based largely on descriptive data and expert opinion.

To address the above questions of whether the IHR of all ICU patients in a single day is associated with changes in vital signs and worse clinical outcomes, we conducted a prospective observational study to test the hypothesis that in the setting of adherence to an IHR protocol, IHR would not be associated with a decrease in arterial oxygen saturation or blood pressure or an increase in heart rate. Additionally, we hypothesized that exposing critically ill adults to IHR would not be associated with increased inhospital mortality.

Methods

Study Design

The ICU MOVE (the effect of an Intensive Care Unit Move on Outcomes, safety Variables, and processes of carE) study was a prospective, observational cohort study of all patients admitted to all of the ICUs of a tertiary medical center during a 90-day period spanning a hospital relocation in which all ICU patients were planned to undergo IHR to a new facility in a single day. The study protocol was approved by the institutional review board at the Louisiana State University Health Sciences Center New Orleans with a waiver of informed consent.

Study Participants

All critically ill patients occupying an ICU bed at the Interim LSU Hospital (ILH, preexisting hospital) and University Medical Center New Orleans (UMCNO, newly constructed hospital) were enrolled in 3 different time periods: 30 days before ICU relocation (ILH), 30 days after ICU relocation (UMCNO), and a 30-day enrollment period 1 year after ICU relocation (UMCNO). No patients were excluded from enrollment due to the observational, minimal risk nature of the study. Among this 90-day cohort, ICU patients who were physically transported from ILH to UMCNO on the day of hospital relocation were considered to have been exposed to IHR. The control group consisted of all patients admitted to the same study ICUs in the 90-day period spanning the IHR who were not transported from ILH to UMCNO.

The IHR was conducted with an ICU relocation protocol developed by the investigators (Online Supplement). This protocol included simulated IHR in the months prior to IHR, ICU staffing models for the day of IHR, identification of patients at risk of transport complications, clinical stability criteria for transport, transport procedures, and intake procedures at the destination ICU. Patients were transported from the ILH medical ICU (16 beds) and trauma ICU (20 beds) to the UMCNO medical ICU (18 beds) and trauma ICU (20 beds) utilizing a 1:1 nursing ratio on the day of IHR. In addition to each patient’s bedside ICU nurse, every patient underwent IHR with 2 emergency medical technicians. It was at the discretion of the ICU attending if a patient was also transported with a respiratory therapist or physician and if preemptive analgesia or anxiolysis would be given prior to transport.

Data Collection

Clinical data included baseline demographics, chronic health conditions, primary ICU admitting diagnosis, and severity of illness scoring on ICU admission (Acute Physiology and Chronic Health Evaluation II, Sequential Organ Failure Assessment [SOFA], and injury severity score, if applicable) on all patients occupying an ICU bed during the observation period. Study outcomes included changes in physiologic parameters (heart rate, blood pressure, respiratory rate, arterial oxygen saturation, temperature, pain score), and clinical outcomes included inhospital mortality, ventilator-free days, and ICU-free days. Each bedside ICU nurse underwent IHR with their patient and on arrival reported additional study outcomes, including intratransport device removal or malfunction, new or increased medication administration, fluid administration, changes in ventilator settings, changes in vital signs, and any interventions provided in response to a change in vital signs. Finally, outcomes including the duration of transport (time of departure from origin ICU room subtracted from time of arrival in destination ICU room), order in which the patient was transported, and the number of accompanying emergency medical technicians, nurses, respiratory therapists, and physicians with each IHR patient were recorded.

Data were collected on patients who were exposed to IHR immediately before departure from the origin ICU and again on arrival in the new ICU. All patients undergoing invasive mechanical ventilation were transitioned to the Zoll EMV+ 731 Series portable ventilator in the origin ICU room for transport ventilation, and none were ventilated by hand. If patients were receiving continuous infusions, there were continued with the same pump (Alaris Medley 8015) during transport. A complete description of the preparatory steps and conduct of the single-day IHR of all ICU patients can be found in the Online Supplement.

Statistical Analysis

We conducted 2 types of analyses. First, among patients exposed to IHR, we compared vital signs measured on departure from the origin ICU to vital signs measured on arrival to the destination ICU using the Wilcoxon signed-rank test for paired continuous data. Second, we compared ICU patients exposed to IHR to patients admitted during the study period but not exposed to IHR with regard to inhospital mortality, ventilator-free days, and ICU-free days to day 28 using univariate analysis and multivariable modeling accounting for severity of illness and the presence of traumatic injuries. Median and interquartile ranges (IQRs) are presented for continuous variables and frequencies for categorical variables. Univariate analyses of continuous variables were conducted using Wilcoxon signed-rank test for paired data and Wilcoxon rank-sum test for unpaired data. Categorical variables were compared using Fisher exact test. Correlations between 2 continuous variables were performed with Spearman ρ. All analyses were performed using SPSS Statistics v.22 (IBM Corp, Armonk, New York); a 2-sided significance level of .05 was used for statistical inference.

Results

Baseline Characteristics

A total of 699 critically ill patients were admitted to the ICUs during the 90-day observation period. Of these, 24 patients were exposed to IHR during the single-day hospital relocation (Figure 1). Compared with critically ill patients not exposed to IHR, critically ill patients exposed to IHR had greater severity of illness as measured by SOFA scoring and were more likely to be critically ill due to traumatic injuries (Table 1, eTable 1).

Table 1.

Baseline Characteristics.^a,b

Characteristic	Not Exposed to Interhospital ICU Relocation (n = 675)	Interhospital ICU Relocation (n = 24)	P Value
Age, years	51 (37-60)	48 (29-56)	.31
Men, n (%)	460 (68.2)	18 (75)	.65
African American, n (%)	391 (57.9)	13 (54)	.83
Body mass index, kg/m²	25 (22-31)	24 (22-30)	.88
APACHE II score	18 (14-24)	20 (18-25)	.09
SOFA score	4 (2-7)	7 (3-10)	.004
Location prior to ICU admission, n (%)			.24
Emergency department	510 (75.6)	21 (87)
Hospital floor	66 (9.8)	2 (8)
Operating room	86 (12.7)	0
Outside hospital	13 (1.9)	1 (4)
Admitting ICU service, n (%)			.19
Medical	372 (55.1)	9 (37)
Trauma	189 (28)	12 (50)
Cardiothoracic surgery	34 (5)	2 (8)
Surgery	37 (5.5)	1 (4)
Neurosurgery	25 (3.7)	0
Cardiology	18 (2.7)	0
Primary ICU diagnosis, n (%)
Trauma	170 (25.2)	12 (50)	.01
Injury severity score	13 (9-22)	11 (5-19)	.53
Blunt trauma	122 (71.7)	6 (50)	.18
Nontrauma	505 (74.8)	12 (50)	.009
Septic shock	35 (5.2)	3 (12)
Severe sepsis	50 (7.4)	2 (8)
Postoperative monitoring	86 (12.7)	0
Cardiac arrest	30 (4.4)	0
Overdose	37 (5.5)	1 (4)
Stroke	35 (5.2)	0
Gastrointestinal blood loss	20 (3)	1 (4)
Alcohol withdrawal	16 (2.4)	1 (4)
Cardiogenic shock	10 (1.5)	1 (4)
Aortic dissection	2 (0.3)	2 (8)
Other^c	184 (27)	1 (4)

Abbreviations: APACHE, Acute Physiology and Chronic Health Evaluation; SOFA, Sequential Organ Failure Assessment; ICU, intensive care unit.

^aData are given as median (25th percentile-75th percentile) or number (percentage) of patients.

^bP value = Mann-Whitney U test for continuous variables, Fisher exact test for categorical variables, and χ² for a trend for categorical variables with more than 2 groups.

^cFor expanded baseline characteristics, see eTable.

Of the 24 patients exposed to IHR, on the day of relocation, 7 (29%) were receiving invasive mechanical ventilation, 4 (16%) were receiving continuous infusions of vasopressors, and 1 (4%) was undergoing prone positioning for the treatment of the acute respiratory distress syndrome (eTable 2). These patients had a median of 4 (IQR: 3-6) external or indwelling devices immediately prior to IHR and the median ICU length of stay prior to IHR was 3 days (IQR: 1-14).

Changes in IHR Variables

Among the 24 patients exposed to IHR, there was no significant change in heart rate, mean arterial blood pressure (MAP), or SpO₂ when comparing measurements taken at the time of departure from the origin ICU room with measurements taken at the time of arrival to the destination ICU room (Figure 2, eFigure 1). Additionally, there was no significant change in any other vital sign, pain scale score, or arterial blood gas measurement (eTable 3). There were no intratransport changes in rates of continuous infusions or invasive mechanical ventilator settings (Fio ₂, positive end-expiratory pressure, tidal volume). All external and indwelling devices present at the time of departure remained in place at the time of arrival, nurses reported no device dislodgements, and no patients required placement of a new device within 6 hours of arrival in the destination ICU. During transport, nurses reported 3 (12.5%) patients were given additional analgesia for high baseline pain score or sedation for agitation. The median duration of transport was 28 minutes (IQR: 24-35) over a distance of 0.4 miles between the origin and destination hospitals (eFigure 2), and patients were transported with a median of 3 health-care personnel in critical care transport ambulances (eTable 2).

Subgroup Analyses

The subgroups of patients undergoing invasive mechanical ventilation and patients receiving continuous infusions of vasopressors for shock may be more susceptible to changes in vital signs during IHR.^5
–7,10 Among the 7 patients undergoing IHR while receiving invasive mechanical ventilation, there was no significant change in SpO₂ (eFigure 3a) with stable settings of Fio ₂ and positive end-expiratory pressure during IHR. Four patients were transported while receiving continuous infusions of vasopressors, and there were no changes in infusion rates or fluid boluses during transport. There was no significant change in heart rate in patients receiving vasopressors (eFigure 3b); however, there was a significant increase in MAP in patients receiving vasopressors compared with patients not receiving vasopressors (eFigure 3c).

Of the 24 patients exposed to IHR, 17 (70.8%) were transported with 3 health-care personnel, 3 (12.5%) with 4 health-care personnel, and 4 (16.7%) with 5 health-care personnel. The number of healthcare personnel accompanying the patient during IHR was associated with an increase in MAP (r_s = .48, P = .01); however, there was no association with changes in heart rate or SpO₂ (eTable 4). There was no correlation between duration of transport or order of transport (1-24) and change in heart rate, blood pressure, or SpO₂.

Clinical Outcomes

There was no difference in inhospital mortality in the patients exposed to IHR during ICU relocation (8.3%) compared with patients who were not exposed to IHR (9.2%, P > .99; Figure 3). Exposure to IHR was not associated with fewer ventilator-free days (27 days, IQR 14-28 compared with 28 days, IQR 27-28, P = .07). However, IHR was associated with fewer ICU-free days (16 days, IQR 0-25 compared with 26 days, IQR 24-27, P < .001; Table 2), but this analysis included a median of 3 ICU days (IQR 1-14) prior to IHR exposure (eFigure 4). Additionally, patients exposed to IHR had significantly greater severity of illness as measured by SOFA scoring and were more likely to be critically ill from traumatic injuries at baseline compared to patients not exposed to IHR. After adjusting for the baseline imbalance in SOFA score and trauma diagnosis, there remained no association between IHR and inhospital mortality or ventilator-free days but IHR remained associated with fewer ICU-free days (Table 2).

Table 2.

Clinical Outcomes for Patients Not Exposed to Interhospital ICU Relocation Compared With Patients Exposed to Interhospital ICU Relocation.^a,b

Clinical Outcomes	Not Exposed to Interhospital ICU Relocation (n = 675)	Interhospital ICU Relocation (n = 24)	P Value	Adjusted P Value^c
Inhospital mortality, n (%)	62 (9.2)	2 (8.3)	>.99	.25
Ventilator-free days	28 (27-28)	27 (14-28)	.07	.25
Intensive care unit-free days	26 (24-27)	16 (0-25)	<.001	<.001

^aData given as median (25th percentile-75th percentile) or number (percentage) of patients.

^bP value = Mann-Whitney U test for continuous variables and Fisher exact test for categorical variables.

^cAdjusted P value = logistic (mortality outcome) and linear (VFD and ICUFD outcomes) regression adjusting for baseline imbalance in Sequential Organ Failure Assessment (SOFA) score and trauma diagnosis.

Note. VFD, Ventilator-Free Days; ICUFD, ICU-Free Days.

Discussion

In the setting of implementing an ICU relocation protocol, this prospective cohort study of critically ill adults undergoing IHR in a single day during a planned hospital relocation showed that IHR is not associated with a change in vital signs, device removal, or worse clinical outcomes.

Hospital, including ICU, relocation occurs frequently around the world; however, past literature has focused on the unplanned evacuations of hospitals in the setting of pandemics and disasters.^3,4,9 Adverse events, such as device removal, interruption of medications, and change in vital signs,^5,6,11 can be clinically significant, with approximately 15% of patients experiencing a decrease in oxygen saturation by at least 10% or a change in blood pressure by more than 20 mm Hg from baseline.¹² The ICU relocation protocol used during this IHR targeted these reported adverse events by simulating IHR to practice securing devices, developing a communication network to treat intratransport vital sign changes, and included a pretransport checklist to ensure nurses had secured devices, brought enough medications to avoid interruptions, and ensured hemodynamic stability prior to departure.

The current study was a prospective observation of IHR of all critically ill adults in a single day from an existing hospital to a newly constructed hospital using a unique ICU relocation protocol (Online Supplement) based on published guidelines for the transport of a single ICU patient.¹⁰ This ICU relocation protocol included (1) planning and simulated relocations of mock patients that began 8 months prior to IHR, (2) monitoring of ICU census and staffing in the days prior to IHR, (3) a leadership structure for the day of IHR, (4) a nursing pretransport checklist, (5) a transport severity of illness assigned to each patient, (6) selection of order transport for each patient, (7) limits on the number of simultaneous transports, (8) staffing structure for the origin, ambulance, and destination, and (9) real-time communication between the leadership structure and staff.

In the setting of extensive planning, preparation, and adherence to a unique ICU relocation protocol, we observed none of the adverse events previously described to be associated with transport,^5,6,12 nor was exposure to IHR associated with worse clinical outcomes. The IHR was associated with fewer ICU-free days; however, the calculation of this free-day variable in the 24 patients exposed to IHR included up to 59 ICU days that occurred prior to being exposed to IHR. In the analysis comparing vital sign measurements between departure and arrival time points, we were adequately powered to detect clinically significant changes (eTable 3) and found none. However, because vital sign measurements occurred on departure from the origin ICU and arrival in the destination ICU, it is possible that clinically significant vital sign changes or device removals occurred in the transport vehicle. We are reassured this was not the case since the transport nurses reported none of these events, no changes occurred in medication infusion rates or ventilator settings, no patient required a procedure within 6 hours of arrival, and there was no difference in mortality compared with patients not exposed to IHR.

There are a number of potential explanations why the adverse events associated with transport of a single ICU patient observed in past studies were not observed in the current study. Extensive preparation for IHR began 8 months prior to the day of IHR with preparatory steps previously discussed. The ICU relocation protocol included a number of items that ensured the stability of the patient prior to transport (nursing pretransport checklist, Online Supplement) and delayed the transport of patients until stability was achieved. The median duration of transport in the current study was 28 minutes over a 0.4-mile distance, whereas a past study reporting a higher rate of adverse events had a median transport time of 66 minutes over a 18.6-mile distance.¹² Finally, the observation that the number of transport staff accompanying the patient during IHR was associated with an increase in blood pressure is hypothesis generating, however, may also be related to pain or anxiety during IHR as preemptive pain and anxiety management was not mandated by the protocol.

Our study has several strengths. To our knowledge, this is the first observation of the IHR of all critically ill adults in a single day during a planned hospital relocation. Detailed accounting occurred of the patients transported, personnel and timing of transport, devices, and patient status before, during, and after IHR. Patients exposed to IHR were compared to a large cohort of heterogeneous ICU patients from the same hospitals immediately before and after hospital relocation. Patient-centered outcomes were also collected to determine whether IHR was associated with adverse events beyond vital sign changes and device removal.

Our study has a number of limitations. Despite data collection prior to, during, and after IHR, it remains possible that the study missed vital sign changes and device removal during IHR. The 24 patients remaining in the ICU on the day of hospital relocation and exposed to IHR were clinically different (higher severity of illness and were more likely to be critically ill from traumatic injuries) from the cohort of ICU patients not exposed to IHR. The potential for observer bias exists as study staff were aware of a patient’s exposure to IHR. Although the sample size of 24 patients exposed to IHR is small, paired analyses were adequately powered to detect clinically meaningful changes in vital signs. Finally, ICU leadership developed a unique ICU relocation protocol for this event that was associated with no detectable adverse events, yet it remains unknown whether any variation of this protocol would have the same result.

The results of this study suggest that the IHR of all critically ill adults as part of a single-day hospital relocation is safe and not associated with increased risk beyond usual care. Planned hospital relocation with IHR of ICU patients is a common event, and future research should focus on larger sample sizes of patients exposed to IHR and comparisons of specific preparatory steps. With future comparative studies, lessons learned from hospitals with the luxury of planned relocations can inform hospitals during disaster scenarios^3,4,9 regarding the necessary steps to evacuate an ICU.

Conclusions

In the setting of extensive preparation and adherence to an ICU relocation protocol, the IHR of all critically ill adults during a single day is not associated with changes in vital signs, device removal, or worse clinical outcomes.

Supplemental Material

Supplement - Effect of Interhospital ICU Relocation on Patient Physiology and Clinical Outcomes

Supplement for Effect of Interhospital ICU Relocation on Patient Physiology and Clinical Outcomes by David R. Janz, Yasin A. Khan, Jennifer L. Mooney, Matthew W. Semler, Todd W. Rice, Jessica L. Johnson, Bennett P. deBoisblanc and for the ICU MOVE Investigators and the Pragmatic Critical Care Research Group in Journal of Intensive Care Medicine

Footnotes

Appendix

Acknowledgments

The authors would like to thank the patients, nurses, respiratory therapists, residents, and attending physicians of the Interim LSU Hospital and University Medical Center New Orleans for making this study possible.

Authors’ Note

David R. Janz, Yasin A. Khan, Matthew W. Semler, Todd W. Rice, and Bennett P. deBoisblanc contributed to study concept and design. David R. Janz, Yasin A. Khan, Jennifer L. Mooney, and Jessica L. Johnson contributed to acquisition of data. David R. Janz, Matthew W. Semler, Todd W. Rice, Bennett P. deBoisblanc contributed to statistical analysis and interpretation of data. David R. Janz, Yasin A. Khan, and Bennett P. deBoisblanc contributed to drafting of the manuscript. All authors and investigators contributed to critical revision of the manuscript for important intellectual content. David R. Janz, Yasin A. Khan, and Bennett P. deBoisblanc contributed to study supervision. David R. Janz and Bennett P. deBoisblanc had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. David R. Janz, Matthew W. Semler, and Todd W. Rice conducted and are responsible for the data analysis. A portion of this work has been previously presented in abstract form at the American Thoracic Society International Conference in San Francisco, 2016. A full list of the ICU MOVE Investigators can be found in the . All authors have completed and submitted the ICMJE form for disclosure of potential conflicts of interest.

Declaration of Conflicting Interests

The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Todd W. Rice reported serving on an advisory board for Avisa Pharma, LLC, as a DSMB member for GlaxoSmithKline PLC, and director of Medical Affairs for Cumberland Pharmaceuticals, Inc.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Investigators conducting this study were supported by a National Heart, Lung, and Blood Institute (NHLBI) T32 award (HL087738 09). Data collection utilized the Research Electronic Data Capture (REDCap) tool developed and maintained with Vanderbilt Institute for Clinical and Translational Research grant support (UL1 TR000445 from NCATS/NIH) and hosted at the LSUHSC New Orleans School of Public Health. The funding institutions had no role in (1) conception, design, or conduct of the study, (2) collection, management, analysis, interpretation, or presentation of the data, or (3) preparation, review, or approval of the manuscript.

Supplemental Material

Supplemental material for this article is available online

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