Nursing interventions for critically ill traumatic brain injury patients.
Neuroscience intensive care unit (ICU) nurses deliver a number of interventions when caring for critically ill traumatic brain injury (TBI) patients. Yet, there is little research evidence documenting specific nursing interventions performed. As part of a larger study investigating ICU nurse judgments about secondary brain injury, ICU nurses were asked to identify interventions routinely performed when caring for TBI patients. Quantitative and qualitative analyses indicate that all nurses routinely monitored hemodynamic parameters such as oxygen saturation, blood pressure, and temperature. Nurses were responsible for monitoring intracranial pressure and cerebral perfusion pressure approximately 50% of the time. Qualitative analyses revealed that additional nursing interventions could be categorized as neurophysiological interventions, psychosocial interventions, injury prevention interventions, and interventions to maintain a therapeutic milieu. Findings from this study provide evidence of the multifaceted role of the neuroscience ICU nurse caring for TBI patients and can be used in future research investigating the impact of nursing interventions on patient outcomes.
Traumatic brain injuries (TBIs) account for over 200,000 hospital admissions every year in the United States, costing over 3.2 billion healthcare dollars annually (Langlois, Rutland-Brown, & Thomas, 2006; Russo & Steiner, 2007). It is estimated that 71% of TBI hospitalizations are for patients with severe injuries necessitating critical care monitoring (Russo & Steiner, 2007). Neuroscience intensive care unit (ICU) nurses deliver a myriad of interventions when caring for these critically ill TBI patients. Yet, there is little research evidence documenting specific interventions performed. This information is needed to highlight the autonomy and role of the neuroscience ICU nurse when caring for critically ill TBI patients and as a basis for future research investigating how nursing interventions impact patient outcomes. Therefore, the purpose of this article was to present findings from a research study in which neuroscience ICU nurses described interventions routinely performed when caring for TBI patients.
Descriptions of Nursing Interventions
Several reports identify nursing interventions for critically ill TBI patients. Although these reports are not based on research evidence, they do provide general descriptions of ICU nurse responsibilities when caring for TBI and other neurologically impaired patients (Ladanyi & Elliot, 2008; Littlejohns & Bader, 2009; Olson & Graffagnino, 2005; Presciutti, 2006; Wong, 2000). Responsibilities include monitoring patient physiological parameters and ensuring hemodynamic stability, performing serial neurological examinations, preventing secondary injury, and providing emotional support for patients and families (Chamberlain, 1998; Olson & Graffagnino, 2005; Presciutti, 2006). More recently, ICU nurses are involved with advanced technologies, such as monitoring and maintenance of brain tissue oxygenation and monitoring electroencephalograph and bispectral index readings (Albano, Comandante & Nolan, 2005; Bader, Littlejohns, & March, 2003; Littlejohns & Bader, 2009). Collectively, these described interventions comprise the multifaceted role of nurses caring for TBI patients in the ICU, where technical and interpersonal competencies are crucial.
Nursing Priorities of Care
The interventions described earlier are often guided by nursing priorities that have been identified in the research literature (Fonteyn & Fisher, 1994; Villanueva, 1999). Two qualitative studies specifically describe nursing priorities and associated interventions when caring for critically ill neurologically impaired patients. A key priority when caring for unconscious patients is "giving the patient a chance," in which interventions center on learning about the patient, maintaining and monitoring patient status, talking to the patient, and working with the family (Villanueva, 1999).
In a separate study, nurse priorities when caring for postoperative craniotomy patients are the following: (a) The patient will become responsive and (b) the patient will remain hemodynamically stable (Fonteyn & Fisher, 1994). Nursing interventions related to these priorities include assessments of patients' level of consciousness or neurological status, blood pressure (BP), breath sounds, temperature, amount of respiratory secretions, central venous pressure, heart rate and rhythm, pulse pressure, and arterial blood gases. These studies contribute information about nursing priorities guiding interventions for neurologically impaired patients in the ICU. However, findings from these studies are limited by small sample sizes (n = 16 and n = 3, respectively), and interventions described are not specific to the complex care often required for critically ill TBI patients.
Factors Influencing Nurse Interventions
The presence of external factors can influence nursing interventions performed with neurologically impaired patients (Cook, Deeny, & Thompson, 2004; McNett, 2009; McNett, Doheny, Sedlak & Ludwick, 2009). Nursing judgments about appropriate interventions when managing secondary brain injury in critically ill TBI patients are influenced by worsening values for oxygen saturation, intracranial pressure (ICP), cerebral perfusion pressure (CPP), and nursing shift. Nurses are less likely to rely solely on nursing interventions and more likely to consult another member of the healthcare team as values for oxygen saturation, ICP, and CPP fall farther from recommended parameters. In addition, nurses working day shift are more likely to rely solely on nursing interventions and less likely to consult other healthcare team members than are their night shift colleagues (McNett, 2009).
When managing subarachnoid hemorrhage, neuroscience ICU nurses are influenced by knowledge of current standards and therapies for fluid and hydration management. Judgments about interventions center on the nursing process of assessment, planning, implementation, and evaluation. Using this process, nurses rely on patient cues, such as physical appearance, recorded intake-output, and neurological status when determining need for interventions (Neal & Deeny, 2004). When managing fever in neurologically impaired patients, nurses describe decisions about interventions being influenced by the individual nurse, the patient, and the barriers present within the organization or nursing unit (Thompson, Kirkness & Mitchell, 2007).
The studies mentioned contribute information about nursing priorities and factors influencing nurse interventions for neurologically impaired patients. However, there is no research evidence documenting specific interventions performed by ICU nurses when caring for critically ill TBI patients. The purpose of this article therefore was to present findings from a research study in which neuroscience ICU nurses reported routine interventions administered when caring for TBI patients.
The findings presented here are part of a larger study investigating ICU nurse judgments about secondary brain injury using a prospective factorial survey research design (McNett, 2009; McNett et al., 2009). Approval for the study was obtained from the institutional review boards and nursing administration at both study sites. An anonymous survey was administered to 67 nurses working in three ICUs from two level I trauma centers who routinely care for critically ill TBI patients. Both study sites were designated as level I trauma centers by the American College of Surgeons and were classified as large teaching hospitals. Both were similar in terms of delivery and structure of nursing care, staffing ratios, and nurse characteristics. Study site A had a larger trauma volume, admitting approximately 3,000 trauma patients per year, whereas study site B averaged 1,000 trauma admissions annually. Study site A had recently identified the Guidelines for the Management of Severe Traumatic Brain Injury (Brain Trauma Foundation, American Association of Neurological Surgeons, The Joint Section on Neurotrauma of Critical Care, 2007) as a reference to guide care of the critically ill TBI patient in their ICUs. However, there were no standing order sets or standardized care plans in place for critically ill TBI patients at either study site.
Nurses from both sites were invited to participate in the study if they held an active state license as a registered nurse; were employed full-time, part-time, or per diem as a clinical bedside nurse in an ICU that admits critically ill TBI patients; and were employed in the current ICU for a minimum of 3 months. Nurses were excluded if they did not have experience caring for critically ill TBI patients, were currently in nursing orientation, or were not directly responsible for the continuous bedside monitoring and delivery of care to critically ill TBI patients in that ICU. A power analysis indicated that a sample size of 60 would be sufficient to detect a medium small effect size of .20 with a power of .80.
Nurses in the ICU were approached during unit staff meetings and change-of-shift report times and invited to participate in the study. The study survey had three parts: Part A contained a series of questions about the last TBI patient nurses cared for in their unit and interventions typically performed when caring for these patients, part B contained case scenarios in which nurses were asked to indicate judgments they were most likely to make, and part C gathered demographic information about nurse respondents. Findings from the latter two survey sections have been previously reported (McNett, 2009). In this article, findings from survey part A (nurse interventions) are presented.
Part A of the study survey contained six fixed-response questions about the last TBI patient nurses cared for in their ICU. Nurses were asked how long ago they took care of a TBI patient, which physiological parameters they were responsible for managing, and the patient's mechanism of injury, age, gender, and comorbidities. Content for these questions was derived from an extensive review of the literature describing various nursing interventions and was validated by a team of clinical nurses and two clinical nurse specialists who routinely care for critically ill TBI patients. A final open-ended question on the study survey asked nurses to identify using free-text responses what interventions they performed when caring for this patient.
Descriptive analyses, including means, standard deviations, and frequencies, were performed, with the quantitative data gathered from the fixed-response questions on the study survey. Methods for qualitative data analyses outlined by Pope and Mays (1999) were then performed with the free-text responses nurses provided. All free-text responses were recorded and systematically reviewed using first-level coding to identify recurring phrases and commonalities among responses. The constant comparison method was used to ensure that the identified codes were inclusive of all data. These first-level codes were then reviewed and grouped into larger categories using second-level coding, which described the types of interventions performed by nurses. The recorded data, initial codes, and overall themes were reviewed by a second investigator with extensive neurocritical care experience to validate the findings.
Table 1 presents a summary of the characteristics of nurse respondents. A total of 67 nurses returned completed surveys, yielding a 44% response rate. Most nurses in the study were between the ages of 26 and 40 years (64%), Caucasian (92.4%), and women (76.1%). Many nurses had less than 10 years of experience working in the ICU (70.1%) and caring for TBI patients (74.6%). Over half of the nurses (58%) held bachelor degrees, and primary shifts included days (25.4%), day-night rotating (29.9%), day-evening rotating (10.4%), evenings (1.5%), and nights (32.8%).
Descriptive analyses were used to analyze the first six questions on the study survey. ICU nurses were asked to indicate how long ago they last cared for a TBI patient in their unit and which physiological parameters they were responsible for managing and to identify the patient's mechanism of injury, gender, age, and comorbidities. Table 2 provides a summary of ICU nurse responses.
All ICU nurses had cared for a critically ill TBI patient either within the last week (65.7%) or month (34.3%). ICU nurses indicated that they were responsible for monitoring BP, oxygen saturation, and temperature among all of these recent patients. Approximately 50% of nurses indicated that they were also responsible for monitoring ICP and CPR Most nurses described their most recent TB! patients as male patients (85%), between the ages of 36 and 65 years (55.2%), and being injured from a motor vehicle crash (46.3%). Over 60% of patients recently cared for by nurses had also experienced extracranial injuries requiring additional nursing care, and smaller percentages of patients had other comorbidities, such as hypertension (34.3%) or diabetes (14.9%).
Nurses in the ICU were then asked to identify additional nursing interventions performed when caring for their most recent TBI patient. Qualitative analyses of these responses indicated that interventions could be grouped into four categories: neurophysiological interventions, psychosocial interventions, injury prevention interventions, and interventions to maintain therapeutic milieu. Figure 1 displays each category and the corresponding interventions reported by nurses.
Nurses in the ICU reported being responsible for monitoring and maintaining various physiological parameters to ensure neurological stability in patients. Consistent with their responses to the quantitative questions, nurses described monitoring patient oxygen saturation, BP, ICP, CPP, and temperature. In addition to these parameters, nurses also monitored pulmonary artery and central venous pressure readings, cerebral spinal fluid drainage, serial laboratory values, and carbon dioxide parameters. By keeping these values within acceptable limits, nurses were preventing secondary brain injury and promoting neurological stability. Additional interventions to monitor neurological stability included performing neurological assessments at a minimum of every hour and transporting and monitoring patients for computed axial tomography scan and magnetic resonance imaging testing. Several nurses also cited assisting with brain death examinations and preparing patients for organ donation as other interventions.
Within this category of neurophysiological interventions, nurses provided evidence of specific interventions performed to ensure that the mentioned physiological parameters remained within normal limits. To obtain acceptable values for oxygen saturation, nurses cited being responsible for ventilator management and suctioning. To keep BP, ICP, and CPP within normal limits, nurses administered medications such as mannitol, propofol, and narcotics and kept the patient's head of bed elevated and neck in a midline position. Nurses also administered blood products and closely monitored intake-output to ensure adequate circulating blood volume, thus promoting cerebral perfusion.
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Nurses in the ICU described delivering a variety of interventions that were psychosocial in nature. Interventions in this category involved coordinating meetings and communication between family members and various members of the healthcare team, both in the acute (i.e., coordinating with physicians or organ donation teams) and long-term plans of care (i.e., coordinating with case management, social work). ICU nurses also provided education to family members about the plan of care, possible patient outcomes, and rationale for current therapies. Finally, nurses described simply serving as a source of support for family members by listening and providing necessary reassurance.
Injury Prevention Interventions
The third type of interventions reported by nurses included those aimed at preventing additional patient complications and ensuring patient safety. Within this category, some interventions were specific to TBI patients, such as maintaining spine precautions and frequently reorienting patients. Other interventions were considered routine care for any critically ill patient. These included frequent turning and repositioning of patients to prevent complications of immobility, such as skin breakdown and ventilator-associated pneumonia. ICU nurses also reported ensuring patient safety by preventing falls and determining the need for and monitoring restraint use to prevent disruption of medical devices. All interventions in this category were delivered to ensure a safe environment for patients and to prevent further injury.
Maintaining Therapeutic Milieu
The final category of interventions reported by nurses included those performed to maintain a therapeutic environment for the critically ill TBI patient. These interventions included intangible care given by nurses considering the special needs of TBI patients. Specifically, nurses reported working to limit environmental stimuli for patients. Interventions included regulating visitors, decreasing lighting, and minimizing noise. Many nurses also cited spacing nursing activities to allow for adequate rest periods and to limit increases in ICP.
Neuroscience ICU nurses have an integral role in the care of the critically ill TBI patient. Interventions routinely performed prevent secondary brain injury and patient complications and provide the necessary support and guidance for family members. Yet, there is no research documenting specific interventions associated with this multifaceted role, neither is there data indicating positive outcomes associated with these nursing interventions. These data are needed to acknowledge the unique contribution of ICU nurses as part of the interdisciplinary team caring for TBI patients and as a basis for future research investigating how ICU nurses impact patient and family recovery from TBI during the acute stage of injury.
Findings from this study support the anecdotal descriptions of ICU nurse responsibilities when caring for neurologically impaired patients (Chamberlain, 1998; Ladanyi & Elliot, 2008; Littlejohns & Bader, 2009; Presciutti, 2006). The four categories of interventions described indicate that neuroscience ICU nurses must possess extensive knowledge of the pathophysiological processes associated with primary and secondary brain injury. Nurses must also have the technical skills to effectively manage these processes and ensure neurological stability. Finally, excellent interpersonal skills are crucial to communicate with families and other members of the healthcare team.
When examining the interventions reported by nurses, it is interesting to note that most interventions were classified as neurophysiological, which centered on ensuring the neurological and physiological stability of the patient. This finding is supported by findings from the larger study in which the physiological parameters, specifically a patient's oxygen saturation, ICP, and CPP, were the most significant variables influencing ICU nurse judgments when caring for TBI patients (McNett et al., 2009). This is consistent with smaller qualitative studies concluding that maintenance of physiological and neurological parameters is a priority when caring for neurologically impaired patients (Fonteyn & Fisher, 2004; Villanueva, 1999). Thus, although the ICU nurse caring for critically ill TBI patients is responsible for a number of interventions, it does appear that stabilizing the patient's physiological parameters and neurological status is the key priority. This certainly is of utmost importance because these factors ultimately are what influence patient mortality and outcome.
The study is limited by the fact that data were only gathered from two study sites in one geographical location. As a result, findings may not be generalizable to all neuroscience ICU nurses. In addition, nurses in this study were asked to recall interventions they performed with previous TBI patients and therefore may not remember all interventions delivered when caring for that patient. It is likely that additional interventions were done but not necessarily reported by the nurses in the study. Despite these limitations, findings do provide baseline evidence of specific interventions of ICU nurses. This information is necessary for future research investigating the impact of these interventions on outcomes.
CE TEST QUESTIONS
GENERAL PURPOSE STATEMENT: To familiarize the registered professional nurse with research on nursing interventions for critically ill traumatic brain injury (TBI) patients.
LEARNING OBJECTIVES: After reading this article and completing the test the nurse will be able to:
1. Describe elements of nursing research conducted by the author and others.
2. List, categorize, and prioritize nursing interventions identified in the study.
1. The purpose of the research study undertaken by the authors was to
a. encourage more intensive care unit (ICU) nurses to care for traumatic brain injury (TBI) patients.
b. reduce the cost of care for TBI patients.
c. advocate for better training of ICU nurses caring for TBI patients.
d. describe interventions routinely performed when caring for TBI patients.
2. Findings by Fonteyn and Fisher (1994) are considered limited because
a. the research is old.
b. the sample size was small,
c. the data are qualitative in nature.
d. no control group was used in the study.
3. Consulting with other health professionals about critically ill TBI patients is less likely by nurses who
a. work the day shift,
b. work the evening shift,
c. work the night shift.
d. rotate shifts,
4. The authors invited nurses to participate in the study who, among other criteria,
a. worked full time and had ever provided care to TBI patients.
b. had been employed in an ICU for a minimum of 6 months.
c. worked either fulltime, part-time, or per diem in an ICU that admitted critically ill TBI patients.
d. worked in a hospital that admitted a minimum of 2,000 trauma patients annually.
5. What size study sample was required to detect a medium small effect size of 0.20 with a power of 0.80?
6. The one free text question on the survey asked nurses to
a. identify the psychosocial parameters used in caring for the TBI patient.
b. identify the interventions they performed in caring for the TBI patient.
c. describe the patient family interactions noted in caring for the TBI patient.
d. describe their areas of concern in caring for the TBI patient,
7. Descriptive data analyses performed on the fixed response questions included
a. means, standard deviations, and frequencies.
b. mode, range, and standard deviation.
c. maximum values, averages, and measures of variation.
d. median, frequency, and range.
8. Sixty-four percent of the nurses who participated in the study ranged in age between
a. 20 and 25 years.
b. 26 and 40 years.
c. 41 and 50 years.
d. 51 and 65 years.
9. The majority of study participants had worked with TBI patients for
a. 0 to 10 years.
b. 11 to 20 years.
c. 21 to 30 years.
d. 31 years or more.
10. Which activity was not categorized as an injury prevention intervention?
a. turning and repositioning
b. monitoring restraint use
c. reorienting patient
d. managing ventilator
11. Which parameters were identified by 100% of the study participants as their responsibility to manage?
a. intracranial pressure (ICP) and cerebral perfusion pressure (CPP)
b. ICP and temperature
c. oxygen saturation ([O.sub.2]sat) and temperature
d. blood pressure (BP) and CPP
12. Almost one third of the 67 patients described in the study ranged in age between
a. 18 to 35 years.
b. 36 to 65 years.
c. 66 to 85 years.
d. over 85 years.
13. The majority of interventions reported by nurses in the study were classified as
b. injury prevention.
c. maintaining therapeutic milieu.
14. The most significant variables influencing ICU nurse judgments when caring for the TBI patient were
a. [O.sub.2]sat, temperature, and BP.
b. ICP, serial lab work, and fluid status.
c. CPP, [O.sub.2]sat, and IOP.
d. neuro checks, BP, and serial lab work.
15. Research reveals that the key priority for ICU nurses when caring for the critically ill TBI patient is
a. injury prevention.
b. neurophysiological maintenance.
c. psychosocial intervention.
d. maintaining a therapeutic milieu.
16. Generalizability of this study's findings is limited by the
a. age of participants.
b. gender of participants.
c. number of participants.
d. geographic location of participants.
17. The author states that data obtained by this study are necessary for
a. future research on the impact of nursing interventions on outcomes in TBI.
b. developing standing orders for the care of TBI patients.
c. developing guidelines for the management of TBI patients.
d. evaluating nursing judgment in the care of TBI patients.
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Question or comments about this article may be directed to Molly M. McNett, PhD RN, at firstname.lastname@example.org. She is a senior nurse researcher at MetroHealth Medical Center, Cleveland, OH.
Anastasia Gianakis, BSN RN CCRN, is a nurse manager at Neurosurgical, Spine, and Surgical Intensive Care Unit, MetroHealth Medical Center, Cleveland, OH.
TABLE 1. Summary of Nurse Characteristics Demographic Characteristics % n Age (years) 25 or younger 9 6 26-40 64 43 41-50 18 12 51 or older 9 6 Gender Male 23.9 16 Female 76.1 51 Ethnicity Caucasian 92.4 61 Other 7.5 5 Years in intensive care unit 0-10 70.1 47 11-20 19.4 13 21 or more 10.4 7 Years with traumatic brain injury 0-10 74.6 50 11-20 16.5 11 21 or more 9.0 6 Highest nursing degree Associate degree 22.4 15 Nursing diploma 19.4 13 Bachelor of science in nursing 58.2 39 Primary shift Days 25.4 17 Day-Night 29.9 20 Day-Evening 10.4 7 Evening 1.5 1 Nights 32.8 22 TABLE 2. Characteristics of Most Recent TBI Patient Last Case Information % n Last time cared for TBI patient Within last week 65.7 44 Within last month 34.3 23 Parameters responsible for managing BP 100 67 O2Sat 100 67 Temperature 100 67 ICP 52.2 35 UP 50.7 34 Other 16.4 11 Patient mechanism of injury Motor vehicle accident 46.3 31 Fall 34.3 23 Assault 10.4 7 Other 9.0 6 Patient gender Male 85.1 57 Female 14.9 10 Patient age (years) 18-35 29.9 20 36-65 55.2 37 66-85 10.4 7 Over 85 4.5 3 Patient comorbidities Extracranial injuries 61.2 41 Hypertension 34.3 23 Diabetes mellitus 14.9 10 Other 10.4 7 Note. TBI = traumatic brain injury; BP = blood pressure; O2Sat = oxygen saturation; ICP = intracranial pressure; CPP = cerebral perfusion pressure.