Adverse events during intrahospital transport of critically ill patients: incidence and risk factors


By: Erika Parmentier-Decrucq, Julien Poissy, Raphaël Favory, Saad Nseir, Thierry Onimus, Mary-Jane Guerry, Alain Durocher & Daniel Mathieu 
Published: Annals of Intensive Care volume 3, Article number: 10
Date: 2013

Management of critically ill patients in the intensive care unit (ICU) requires investigations and therapeutic procedures leading to numerous transports outside the ICU. These intrahospital transports (IHT) are at risk of complication and should be considered as an important part of the ICU risk management program. However, an adverse event (AE) during transport remains common and may induce an important risk for the patient. This risk has to be evaluated by the physician before ordering a diagnostic or therapeutic procedure, based on a benefit/risk analysis in which the risk of the IHT has to be put in balance with the expected benefit of the procedure [1]. Thus, reducing the risk of IHT adverse events is essential to ICU patient management.

Many recommendations are available [26], stemming from personal experience and expert opinion [47]. Several authors have identified effective “protective” factors for limiting AE, such as regular patient [812] and equipment checks [411] during IHT, meticulous preparation of the patient, appropriate sedation [4], a specialised and experienced escort [411], correct use of protocols [13], and diagnostic and therapeutic units located within easy reach of the emergency department or ICU [411]. Also, good clinical sense is required to decrease AE during IHT [1].

Incidence and severity of AE vary according to studies [891114]. These discrepancies may be explained at least in part by differences in definition. The most clinically useful definition of major AE is one that leads to a change of therapy during IHT [13]. Discrepancies also may be explained by the time-period studied: AE can arise during transport or secondarily. Finally, IHT have been suspected to be one of the causes of ventilator-associated pneumonia and their occurrence also should be studied [15].

The main objectives of this observational study were first to determine the frequency and risk factors for AE during IHT of critically ill patients and, second, to determine the consequences of these AE during IHT and what improvements could be put in place in our ICU.


This prospective, observational study was conducted in a 38-bed medical ICU in a regional and teaching hospital in France from May 1, 2009, to March 21, 2010. The Ethics Committee of the Institutional Review Board for the University Hospital of Lille approved the design of our study. Because of the noninterventional nature of our study, patient consent was waived.


Every mechanically ventilated patient who needed IHT for a computed tomography (CT) scan was enrolled. ICU admission before May 1, 2009, ICU discharge after March 21, 2010, IHT for therapeutic procedures, and IHT for investigations other than a CT scan were exclusion criteria.



Before this study was undertaken, a specific protocol for managing IHT was in place in our ICU to limit AE (Additional file 1). Our protocol was in accordance with recommendations in effect at the time of the study and included regular equipment and patient checks [4]. The mechanically ventilated patients were accompanied by a transport team composed of a resident and a porter. The resident is the junior physician directly involved in the daily care of the patient. All residents receive specific training regarding IHT when they start their 6-month training period in the ICU. The four porters have been working in our ICU for many years and have significant experience with IHT of mechanically ventilated patients. During IHT, portable devices with settings adjusted to clinical necessity are used to monitor vital signs.

Data collection

Clinical patient characteristics and IHT characteristics were prospectively recorded. Data were collected through a case report form in part by the porter for nonmedical data and by the resident for medical data and adverse events during IHT. This case report form was created for the study and also included the transport protocol of our ICU. Case report forms were stocked with airway equipment. So for every IHT of ventilated patient, a case report form was distributed by the porter and recovered within 1 hour after patient return to his room when storing airway equipment. All case report forms were recovered by one of the investigators each day.

The following AE were prospectively recorded for all IHT: agitation, accidental pulling out of nasogastric tube, vomiting, peripheral venous catheter incident (accidental dislodgment, disconnection, or thrombosis), central venous catheter incident (disconnection or thrombosis), arterial line incident (disconnection or thrombosis), accidental dislodging of urinary catheter, disconnection of endotracheal tube, and airway equipment were considered minor patient-related AE; oxygen desaturation (pulse oximetry (SpO2) <95% or >5% decrease in SpO2 for more than 1 minute) [16], accidental extubation, accidental central venous catheter removal, disconnection of chest tube, severe hypotension (systolic blood pressure inferior than 90 mmHg or 20 mmHg decrease in systolic or diastolic blood pressure more than 1 minute) [1117], arrhythmia, cardiac arrest were considered major patient-related AE; incidents with airway equipment (alarms, transport ventilator malfunction, or problems with oxygen supply), battery supply problems with the monitor or with infusion pumps were considered equipment-related incidents [8]. Change of therapy during IHT was noted. Fluid challenge was defined by 500 ml of crystalloid or colloid administration. After IHT, subsequent events, such as acute respiratory distress syndrome or ventilator-associated pneumonia, also were recorded. The diagnosis of ventilator-associated pneumonia was made according to the 2005 American Thoracic Society guidelines [18].

Data analysis

Statistical analysis was performed using SPSS software (version 15.0, SPSS, Chicago, IL). Quantitative values were expressed in median with 25th and 75th percentiles and comparisons between groups were made using Mann–Whitney U test. Qualitative data were expressed as values and percentages and compared by Chi-square test. A value of p < 0.05 was considered significant. For discrete numerical values, such as positive end-expiratory pressure (PEEP) level, the optimal threshold value was determined by ROC curve.

Risk factors for AE during IHT were tested first by univariate analysis. Those with a significance level of p < 0.1 were included in a logistic regression with Wald method analysis as independent variables. Results were reported as odds ratios (OR), and statistical significance was ascertained by the 95% confidence interval.



The significance of this article provides insight to the minor and major incidents that may occur during patient transportation. As mentioned minor would include incidents such as agitation, accidental pulling out of nasogastric tube, vomiting, peripheral venous catheter incident (accidental dislodgment, disconnection, or thrombosis) etc. On the other hand, the major incidents included accidental extubation, accidental central venous catheter removal, disconnection of chest tube, severe hypotension etc. All of the incidents that were listed below can be sourced to the medial support team that aid the patient throughout the duration of the transportation. Overlooking or “accidental” occurrences can be rooted at the issues that arise when trying to account for all aspects of travel. This creates the opportunity to dive deeper into the monitoring of patents and enable for the lusted incidents to be accounted for without exercising more effort than what is already contributed when transporting.