Outcomes of interfacility critical care adult patient transp

[Ace844]

Here's an interesting study which looks at a population of pateints which we have all encountered in our profession...Any opinions, or thoughts..?

Outcomes of interfacility critical care adult patient transport: a systematic review

Eddy Fan1, Russell D MacDonald2, 3, Neill KJ Adhikari4, Damon C Scales4, Randy S Wax5, Thomas E Stewart6 and Niall D Ferguson7

1Fellow, Interdepartmental Division of Critical Care Medicine, University of Toronto, 399 Bathurst Street, F2-150, Toronto, Ontario, M5T 2S8, Canada

2Assistant Professor, Division of Emergency Medicine, Department of Medicine, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada

3Medical Director, Research Program, Ontario Air Ambulance, 20 Carlson Court, Suite 400, Toronto, Ontario, M9W 7K6, Canada

4Instructor, Interdepartmental Division of Critical Care Medicine, and Department of Medicine, Division of Respirology, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Rm B7-08, Toronto, Ontario, M4N 3M5, Canada

5Assistant Professor, Interdepartmental Division of Critical Care Medicine, and Department of Medicine, Division of Respirology, Mount Sinai Hospital, University of Toronto, 600 University Avenue, Suite 1818, Toronto, Ontario, M5G 1X5, Canada

6Associate Professor, Interdepartmental Division of Critical Care Medicine, and Department of Medicine, Division of Respirology, Mount Sinai Hospital and University Health Network, University of Toronto, 600 University Avenue, Suite 1818, Toronto, Ontario, M5G 1X5, Canada

7Assistant Professor, Interdepartmental Division of Critical Care Medicine, and Department of Medicine, Division of Respirology, University Health Network, University of Toronto, 399 Bathurst Street, Toronto, Ontario, M5T 2S8, Canada

Critical Care 2006, 10:R6 doi:10.1186/cc3924

The electronic version of this article is the complete one and can be found online at: http://ccforum.com/content/10/1/R6

Received 22 August 2005

Revisions requested 2 October 2005

Revisions received 24 October 2005

Accepted 31 October 2005

Published 1 December 2005

© 2005 Fan et al.; licensee BioMed Central Ltd.

This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. --------------------------------------------------------------------------------

Outline Abstract

Introduction

We aimed to determine the adverse events and important prognostic factors associated with interfacility transport of intubated and mechanically ventilated adult patients.

Methods

We performed a systematic review of MEDLINE, CENTRAL, EMBASE, CINAHL, HEALTHSTAR, and Web of Science (from inception until 10 January 2005) for all clinical studies describing the incidence and predictors of adverse events in intubated and mechanically ventilated adult patients undergoing interfacility transport. The bibliographies of selected articles were also examined.

Results

Five studies (245 patients) met the inclusion criteria. All were case-series and two were prospective in design. Due to the paucity of studies and significant heterogeneity in study population, outcome events, and results, we synthesized data in a qualitative manner. Pre-transport severity of illness was reported in only one study. The most common indication for transport was a need for investigations and/or specialist care (three studies, 220 patients). Transport modalities included air (fixed or rotor wing; 66% of patients) and ground (31%) ambulance, and commercial aircraft (3%). Transport teams included a physician in three studies (220 patients). Death during transfer was rare (n = 1). No other adverse events or significant therapeutic interventions during transport were reported. One study reported a 19% (28/145) incidence of respiratory alkalosis on arrival and another study documented a 30% overall intensive care unit mortality, while no adverse events or outcomes were reported after arrival in the three other studies.

Conclusion

Insufficient data exist to draw firm conclusions regarding the mortality, morbidity, or risk factors associated with the interfacility transport of intubated and mechanically ventilated adult patients. Further study is required to define the risks and benefits of interfacility transfer in this patient population. Such information is important for the planning and allocation of resources related to transporting critically ill adults.

Regionalization of care and the requirement for specialized resources result in the frequent need for interfacility transport of critically ill patients [1-3]. Although some of these patients may derive significant benefit from such a transfer, they may also be at considerable risk of transport-related morbidity and mortality [4-12]. The decision to initiate the interfacility transport of a critically ill patient must, therefore, be taken carefully. The impact of specific pre-transport and transport-related factors on morbidity and mortality are not well established, however, limiting the ability of clinicians to target particular patients where additional resources and care during transportation might be beneficial. For example, if high-risk patients could be reliably identified, they could undergo additional pre-transport resuscitation [13,14] and/or be accompanied by specially trained transport personnel with additional equipment in order to anticipate and reduce transport-associated risks [15-21].

Several professional societies have developed guidelines for the inter- and intrafacility transport of critically ill patients [22-25]; however, these guidelines focus primarily on general principles (for example, pre-transport stabilization, minimum transport equipment and medications) and the composition of the transport team, rather than risk stratification. Understanding which patients are most at risk while undergoing interfacility transport and the types of events that occur would be an important step in patient preparation and aligning resources (such as equipment and personnel) at the sending and receiving sites as well as during transportation. To this end, we conducted a systematic review of the literature to determine the adverse events associated with interfacility transport of mechanically ventilated adult patients, along with important pre-transport and transport-related prognostic factors.

Identification of trials

Our objective was to identify all relevant published clinical studies describing the incidence and predictors of adverse events in mechanically ventilated adults undergoing interfacility transport. We chose to study only intubated and mechanically ventilated patients in order to capture a well-defined group of critically ill patients with significant severity of illness.

A priori, we defined adverse events related to transportation as those that occurred during interfacility transport and up to 24 hours after arrival at the destination. A computerized MEDLINE (1966 to 10 January 2005) search was conducted using the following medical subject headings: 'transportation of patients', 'intubation, intratracheal', and 'respiration, artificial'. In addition, we searched the databases CENTRAL (first quarter 2005), EMBASE (1980 to 10 January 2005), CINAHL (1982 to 10 January 2005), HEALTHSTAR (1975 to 10 January 2005), and Web of Science (1945 to 10 January 2005) using the keywords: 'transport', 'ventilation', and 'intubation'. No language restrictions were applied. Bibliographies of all selected articles and review articles [26,27] on interfacility patient transport were examined for other relevant studies. This strategy was performed iteratively, until no new clinical trial citations were found on review of the reference lists of retrieved articles. Full details of the searches are available upon request.

Study selection and data abstraction/analysis

The following selection criteria were used to identify published studies for inclusion in our analysis: clinical trial or cohort study or case-series (study design); all patients intubated and mechanically ventilated, and aged ≥ 18 years (study population); and interfacility transport (for example, from one health care facility to another health care facility). Interfacility transports between two sites of the same institution were included if the means of transportation involved air or ground ambulance.

Two reviewers (EF and RDM) independently applied the selection criteria and abstracted the data using standardized forms. The reviewers abstracted data on description of the cohort, methods, adverse events/outcomes, and transport-related interventions. We report descriptive data from individual trials as mean ± standard deviation, unless otherwise stated. Because of the paucity of studies and the heterogeneity in study populations and reported outcomes, we did not conduct a meta-analysis.

Outline Results

Table 1

Characteristics of included studies

Table 2

Transport characteristics of included studies

Table 3

Results of included studies

The combined computerized and bibliographic literature search yielded 599 potentially relevant studies, of which 24 articles were identified for more detailed review (Figure 1). Only five studies satisfied our inclusion criteria [28-32]. There was moderate initial agreement between reviewers for study inclusion (raw agreement = 0.80, chance-corrected agreement κ = 0.65 ± 0.16); all disagreements were resolved by consensus.

The five included studies (Tables 1 and 2) enrolled 245 critically ill patients (median 15; range 8 to 146) with a wide variety of diagnoses. All were case-series, two of which were prospective. The most common indication for interfacility transport was the need for investigations and/or specialist care not available at the referring institution (three studies, 220 patients) [28,29,31,32]. The results of the included studies are summarized in Table 3.

Pre-transport characteristics

Only 1 study reported severity of illness (Sepsis-related Organ Failure Assessment (SOFA) [33] score of 10 ± 3) prior to transport [31]. Another study reported pre-transport arterial blood gas results from transported burn patients [28]. The other three studies provided little data on pre-transport status that would be useful in standardizing comparisons across patient groups.

Transport characteristics

Modalities used for interfacility transport included air (fixed or rotor wing; 66% of patients) and ground (31%) ambulance, and commercial aircraft (3%). Transport teams included a physician in 3 studies (220 patients) [28,31,32]. In one study, 14 patients (21%) were transported in the prone position because of life-threatening hypoxemia [31]. Death during transport was rare (n = 1) [32]. No other adverse events or significant therapeutic interventions during transport were reported in any of the included studies.

Post-transport characteristics

One study (not the same one that described pre-transport characteristics) reported severity of illness on arrival and outcomes following interfacility transport (mean Acute Physiology and Chronic Health Evaluation (APACHE) II [34] score of 17 ± 6; intensive care unit mortality 30%) [29]. The burn study reported the incidence of respiratory alkalosis on arrival (in 19%) and the survival rate to burn unit discharge (71%) [28]. The presence or absence of post-transport adverse events was not reported in the other three included studies.

Table 4

Barriers to transport research and recommendations for future studies

The main finding of this systematic review is the paucity of studies examining adverse events and their associated risk factors in critically ill patients undergoing interfacility transport. The few published studies suggest that significant mortality or morbidity associated with interfacility transport of intubated adult patients is uncommon; however, there are significant limitations to the available data. First, the estimation of the incidence of adverse events is unreliable because all studies were case series (the majority of which were retrospective) that enrolled few transported patients. Second, associations between pre-transport variables and adverse outcomes could not be determined, both because pre-transport status was poorly documented, and because studies lacked standard definitions and methods for ascertaining adverse events. Finally, many studies only examined immediate or short-term adverse events (for example, during transport or on arrival), even though it is possible that later adverse events may also be associated with important transport-related factors (for example, barotrauma from exposure to high ventilatory pressures during transport may go unrecognized for several hours).

A number of factors may have contributed to the low morbidity of interfacility transport documented in this review. These include the possibility that some patients who were less severely ill were intubated and ventilated solely to facilitate safe transportation, thereby lowering the overall acuity of illness and likelihood of adverse events. The extent to which this practice occurred was not reported in any of the included studies. In addition, the composition of the transport teams may have had an influence. In three of the five included studies, the transport teams included a physician; in two of these the physician was a specialist (a burn surgeon and an intensivist). In addition, a nurse accompanied the patient in all four studies that reported transport team composition. Interfacility transport is increasingly becoming the jurisdiction of highly trained and specialized transport personnel [35-38], with at least one paediatric study demonstrating significantly decreased morbidity associated with the use of such teams [36]. Professional guidelines have suggested that transport of unstable critically ill adults should be accompanied by either a physician or a nurse, preferably with additional training and experience in transport medicine [22]. The results of our review may not have been the same if more data were available from transports without such individuals.

Although transport methods, distance, and time differ in intra-hospital transfers, the risks and types of adverse events for the patient may be similar to those undergoing inter-hospital transport [24,39,40]. Several studies of intra-hospital transfers of critically ill patients have reported transport-related complications [39-42]. In a recent study [42], 191 incidents related to intra-hospital transport were identified over a six year period. The majority of adverse events centered on patient-staff management issues and equipment problems that culminated in serious complications in 31% of reported incidents, including major physiological deterioration in 15% and death in 2% [42]. This relatively high rate of adverse events among reported incidents when intrafacility transport is subjected to close scrutiny further calls into question the validity of the results of our review. It seems likely that the potential for adverse events is significantly higher during air transport between two hospitals than on a trip to another department within the same hospital such as the radiology department. Alternatively, a possible explanation is that patients undergoing intra-hospital transports are sicker and/or the personnel associated with these transports are less experienced than inter-hospital transport teams.

Finally, we acknowledge that a limitation to the generalizability of our results is the restriction of our review to intubated and ventilated patients undergoing interfacility transport. In our attempt to identify and study a well-defined population of critically ill patients, we may have missed other patients at risk for adverse events during interfacility transport.

The lack of informative clinical studies evaluating the interfacility transport of critically ill patients is likely related to a variety of barriers in conducting research in this setting (Table 4). Clearly, deciding if patients will undergo interfacility transport by randomization is infeasible and unethical. Therefore, we believe that a multi-center, prospective observational cohort study is the methodology best suited to address the important questions raised by our review in this rapidly growing field of transit care medicine. In the design of such a study, attention would need to be paid to developing and validating consistent definitions for adverse events. In addition, extensive collaboration between the critical care and transport teams would be essential.

Conclusion

Few data document the risks of interfacility transport. Until more robust risk assessment tools become available, common sense and physiological rationale will continue to guide the risk/benefit assessment of interfacility transport for individual patients. We believe that more research is required to document the prevalence of adverse events in critically ill patients during transport, and to elucidate the associated patient- and transport-related risk factors. Such research could form the basis of new strategies to optimize patient safety. In addition, better identification of patients at risk may allow for more efficient and effective alignment of transport-related resources, such as specialist retrieval teams and enhanced pre-transfer stabilization.

Key messages

• Few data exist regarding the mortality, morbidity, and/or risk factors associated with these outcomes in intubated and mechanically ventilated adult patients undergoing interfacility transport.

• Further prospective study is required to define the risks and benefits of interfacility transfer in this patient population.

• Such information is important for the planning and allocation of resources related to transporting critically ill adults.

Competing interests

The authors declare that they have no competing interests.

Authors' contributions

EF, RDM, DCS, TES, and NDF conceived the study. All authors contributed to the study design and interpretation of the data. EF and RDM performed the literature search and abstracted the data. EF wrote the first draft of the manuscript, which was then revised for intellectually important content by all authors. All authors read and approved the final manuscript.

Ace844

[flight-lp]

Interesting abstract for a study, but overall it seems they really couldn't answer a lot of their own questions. One piece of info that I found kinda humerous..............

"It seems likely that the potential for adverse events is significantly higher during air transport between two hospitals than on a trip to another department within the same hospital such as the radiology department. Alternatively, a possible explanation is that patients undergoing intra-hospital transports are sicker and/or the personnel associated with these transports are less experienced than inter-hospital transport teams."

Gee, ya think!!!!!!!!

Stay in the confines of the controlled environment and of course your risks and outcomes will be better. Pt. goes bad, call a code and you get a lot of multi-disciplinary resourses in a quick manner. But leave the controlled environment with a crew of 2 or 3 people and you are severly limited to what you can immediately get or get to. Plus, if a deterioration occurs outside the hospital, it is well known and documented. Despite the reporting requirements, we all know that not all deteriorations or bad outcomes are reported or documented inside all hospitals. To me this is a biased and not fully researched conclusion.

I do not agree with the last sentence about less experienced transport teams. If a specialized inter-facility transport team is available, great, send them, but the fact of the matter remains that few facilities outside of large tertiary facilities have such capabilities. Most facilities around me will call for air resources which do have the knowledge and educational programs that can appropriately care for the critically ill or injured. For some transports if space limitations are present in the helicopter, then the flight crew will accompany a ground unit for transport.

As far as the air transport aspect goes, yes there is a higher incident of complications. Courtesy of mother nature and the atmosphere of the earth (i.e. coriolis effect), there are more than a few extra considerations that the medical team must consider. Unlike some issues on the ground that you can improvise to correct, the gas laws are unbreakable. You must adapt to their properties or you will have a bad outcome. The study does not include any variables or information relative to this. I agree with the authors, more studies and information needs to be researched.

Great finding though Ace! I enjoy these, keep 'em coming..........................

[Dustdevil]

Gee, ya think!!!!!!!!

That's the same nonsense they tried to pull in the study that showed you were statistically more likely to die if you arrived at the ER by ambulance than by POV. No $hit, Sherlock! I wouldn't have called an ambulance if I wasn't pretty damn sick!

Another case of faulty extrapolation.

When studies go bad. :roll:

[Ace844]

(Acad Emerg Med Volume 13 @ Number 7 746-754,

published online before print May 24, 2006, doi: 10.1197/j.aem.2006.02.014

© 2006 Society for Academic Emergency Medicine CLINICAL PRACTICE

Variability of Trauma Transfer Practices among Non–tertiary Care Hospital Emergency Departments

Craig D. Newgard, MD, MPH, K. John McConnell, PhD and Jerris R. Hedges, MD, MS

From the Center for Policy and Research in Emergency Medicine, Oregon Health & Science University (CDN, KJM, JRH), Portland, OR.

Address for correspondence and reprints: Craig D. Newgard, MD, MPH, Department of Emergency Medicine, Center for Policy and Research in Emergency Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Mail Code CR-114, Portland, OR 97239-3098. Fax: 503-494-4640; e-mail: newgardc@ohsu.edu.)

Objectives: To assess both the variability of interhospital trauma transfer practices and nonclinical factors associated with the transfer of injured patients from emergency departments (EDs) of non–tertiary care hospitals.

Methods: The authors analyzed a retrospective cohort of trauma patients initially presenting to one of 42 non–tertiary care hospitals (Level 3 or 4 hospitals) and requiring admission or transfer from January 1998 to December 2003. Twenty-one clinical, demographic, and hospital-level variables were included in multivariable logistic regression models (outcome = ED transfer to a tertiary care hospital), with hospital and year included as fixed effects to adjust for clustering. Classification and regression tree analysis was used to determine the importance of different covariates in predicting whether or not a patient was transferred from the ED.

Results: Included in the analysis were 10,176 persons, of whom 3,785 (37%) were transferred to a tertiary care hospital from the ED. The hospital of initial presentation was the factor of greatest importance in predicting transfer, and there was substantial variability in transfer practices between hospitals. Several additional nonclinical variables were independently associated with transfer, including type and level of hospital, patient age, increasing distance from the nearest higher-level hospital (a measure of geographic isolation), and the patient's insurance status (particularly among Level 3 hospitals).

Conclusions: The non–tertiary care hospital of initial presentation is the strongest predictor for whether an injured patient is transferred to a tertiary center from the ED. There is substantial variability in transfer practices between hospitals after accounting for important clinical factors, and several nonclinical variables are independently associated with transfer.