Impact of the COVID-19 Pandemic on Nurses Working in Intensive Care Units: A Scoping Review

We conducted an initial search on January 18, 2022, using a broad search strategy in CINAHL Complete, Ovid MEDLINE (1946-present), and OVID Embase (1974-present) in consultation with a research librarian. Date restrictions were applied from 2020 to the present to reflect the timeline of the COVID-19 pandemic. We completed a Google search on January 21, 2022, to obtain grey literature. Peer-reviewed articles and grey literature were included if the topic or data related to nurses working in adult ICUs during the COVID-19 pandemic and the studies explored the impact of redeployment models, pandemic education, and psychological or physical effects of the pandemic. Studies that incorporated other HCPs or units were included as long as nurses working in adult ICUs constituted a portion of the sample and the studies examined provider-specific or unit-specific outcomes. Articles were excluded if they concerned nurses who were not caring for critically ill adult patients with COVID-19, exclusively examined workload activity or tasks, were focused on expansion of pediatric ICUs, or described surge models without exploration of impact on nurses.

Citations were imported into the Mendeley Reference Manager, and duplicates were removed. Citations were screened independently by 2 authors (C.F. and K. K.), first by abstract and title and then by full-text review, with consensus obtained. Grey literature results (obtained via Google search) that did not include an abstract (eg, news articles) and that could not clearly be excluded by title were also included for full-text review to verify inclusion and exclusion criteria. Of conference abstracts included (n = 20), all authors (with 1 exception, where contact information was unavailable) were contacted via whatever means were available (email, ORCID, ResearchGate, social medial platforms) to determine whether a subsequent publication existed. A standardized form was created to record findings from included publications.

In total, the database and grey literature searches generated 553 citations; after 135 duplicate records and 1 record with unavailable full text were removed, 417 records remained for screening. See the Figure for the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, Extension for Scoping Reviews (PRISMA-ScR) flow diagram.⁴ 

A total of 37 peer-reviewed sources (Table 1)^5-41  and 18 grey literature sources (Table 2)^42-59  met the inclusion criteria. The peer-reviewed literature comprised a total of 29 256 HCP participants, of whom 12 486 (42.7%) were identified as ICU nurses and 190 (0.65%) were identified as nurses who were redeployed to ICUs during the pandemic. Thirteen studies differentiated or solely focused on the experience of nurses.^{7,9,12,22,27,28,30,33,34,36-39}  When gender was accounted for (n = 18 646), 72.4% of participants identified as women (n = 13 504).

The dominant theme across the literature was the prevalence of psychological impacts among nurses working in ICUs during the pandemic. Fifty-one sources indicated that nurses experienced negative mental or emotional outcomes, including stress or distress, anxiety, depression, fear, posttraumatic stress disorder (PTSD), and burnout. In total, 26 different tools were employed to understand the impact on HCPs (Tables 1 and 2).

The most frequently used tools to explore anxiety and depression were the Hospital Anxiety and Depression Scale^{5,6,14,22,29,38}  and the 21-item Depression, Anxiety and Stress Scale (DASS-21).^11,12,21  Two studies explored the prevalence of anxiety and depression among ICU nurses exclusively.^12,22  In a national survey of ICU nurses in the Netherlands, 27% experienced anxiety (Hospital Anxiety and Depression Scale score ≥ 8) and almost 1 in 5 reported depression.²²  In another study, just over 40% of ICU nurses in Canada experienced moderate to extremely severe symptoms of anxiety and depression during initial phases of the pandemic.¹² 

Anxiety and depression experienced by nurses during the pandemic differed in severity by whether the nurses worked in COVID-19 versus non–COVID-19 ICUs. A study in Nepal identified no significant differences between unit type, although overall prevalence of anxiety and depression was high.³⁸  Celik and Dagli¹¹  noted that working in a COVID-19 versus a general ICU was associated with higher fear of COVID-19, anxiety, and depressive scores. Of studies exploring the experience of all HCPs working in ICUs, the reported rates of anxiety and depression ranged from 19% to 60% and from 9% to 51%, respectively.^{6,11,14,15,17,21,29}  Mean scores were higher among women in 2 studies.^11,21  Altmayer et al⁵  found that depression scores were significantly higher among permanent ICU staff compared with those redeployed. Dykes et al¹⁵  reported significantly higher anxiety scores using the 7-item Generalized Anxiety Disorder Scale in women, health care aides, and ICU nurses.

Stress was measured in 7 studies using the Perceived Stress Scale and the DASS-21.^{11,12,21,30,37,42,43}  Crowe et al¹²  found that 37.6% of ICU nurses reported moderate to extremely severe stress (DASS-21). In a survey of ICU nurses in Turkey, 83.2% reported moderate to high scores on the 14-item Perceived Stress Scale, with perceived stress higher in women.³⁷  In another study, 22.2% of redeployed nurses in China experienced moderate to high stress, with higher stress scores associated with older age.³⁰  Celik and Dagli¹¹  also noted that stress was higher among nurses and women working in a COVID-19 ICU than in those working in a general ICU. In sources that did not differentiate among HCP respondents, reported prevalence rates of moderate to severe stress ranged from 28% to 70%.^21,42,43  One source indicated that stress levels were significantly higher among women, nurses, those of younger ages, and those of Asian or Black race.⁴² 

Burnout was most frequently assessed in the literature using the Maslach Burnout Inventory.^6,8,13,14,48  Douglas et al¹³  assessed burnout among HCPs in May to June 2020, reporting a rate of 21.4% in the emotional exhaustion category and 12.1% in the depersonalization category. Butera et al⁸  found high rates of burnout among ICU and emergency department nurses, with a significant increase in the rate of burnout among ICU nurses (from 51.2% to 66.7%) from January to April 2020. Risk factors for burnout included increased workload, unavailability of personal protective equipment (PPE), and male gender.⁸  Support from colleagues and supervisors reduced the risk of burnout.⁸  Studies exploring burnout among HCPs in France and Turkey also indicated a high prevalence (45.1% and > 50%, respectively).^6,14  A conference abstract reporting the results of a survey of ICU HCPs in Ukraine indicated a burnout prevalence of 84.5%.⁴⁸ 

The Impact of Event Scale was most frequently used to measure PTSD.^6,12,15,22  Three studies used the Impact of Event Scale-Revised.^6,12,15  Two studies measured PTSD symptoms in ICU nurses exclusively.^12,22  In 1 Canadian center, 37.6% of nurses surveyed in May 2020 reported significant PTSD symptoms, with 12.8% scoring probable symptoms.¹²  Of nurses surveyed in the Netherlands from August to September 2020, 22.2% reported symptoms of PTSD.²²  Two additional studies completed in France and the UK reported a prevalence of PTSD symptoms in ICU HCPs of 28.4% and 28.2%, respectively.^6,15  Dykes et al¹⁵  found that PTSD scores were higher among health care aides and ICU nurses.

Psychological concepts including resiliency, quality of life (QOL), and well-being were examined in 4 studies.^5,13,18,31  In 1 study, despite the prevalence of anxiety, depression, and PTSD, respondent scores trended toward good QOL (McGill Quality of Life Questionnaire) and resiliency (Connor-Davidson Resilience Scale).⁵  Gomez et al¹⁸  used the Stanford Professional Fulfillment Index and the Well-Being Index to report on well-being, professional fulfillment, and burnout among ICU HCPs. Burnout was present in 50% of ICU nurses, with professional fulfillment recorded in 37% of participants. Factors supporting well-being included finding meaning in work and support from colleagues and community.¹⁸  Douglas et al¹³  evaluated HCP well-being and QOL using the Linear Analogue Self-Assessment Scale and European QOL Five-Dimension Scale. Despite high burnout, mean Linear Analogue Self-Assessment Scale and European QOL Five-Dimension Scale scores did not meet the cutoff level for poor QOL or health state.¹³  One study used the Brief Resiliency Coping Scale to measure resiliency and examine experiences of ICU nurses working during the pandemic; the majority of participants were rated as having medium resiliency (44.2%) and high coping skills (77.5%).³¹ 

Physical symptoms commonly accompanied adverse psychological outcomes. The most frequently reported physical symptom was sleep disturbance.^{5,6,13,14,19,21,30,35,38,53,57}  Nurses frequently reported exhaustion.^{8,13,19,30,32-34,45-47,49,51,54}  Two studies used formalized scales to measure physical symptoms.^14,22  Duru¹⁴  explored eating disorder risk (Eating Attitude Test) and sleep quality (Pittsburgh Sleep Quality Index); 19.6% of respondents were at risk for eating disorder, and 96.1% reported poor quality of sleep. The authors also explored suicidal ideation (Suicidal Ideation Scale); no participants scored positive for suicidal thoughts.¹⁴ 

Qualitative methodology was used in 20 peer-reviewed studies, with mixed methods, focus groups, or interviews used to explore the impact of the pandemic. Across studies, 3 main themes were commonly reported: (1) novel challenges of the pandemic, (2) negative impact of the pandemic on ICU nurses, and (3) mitigators of harm during the pandemic.

Several challenges to providing care during the pandemic were identified. Most frequently described was significant uncertainty and rapidly changing working conditions. Bergman et al⁷  described the theme as “tumbling into chaos” and likened the overwhelming situations faced during patient surges to a medical “war zone.” Challenges described by participants included rapid organizational changes, resource scarcity, high patient-to-nurse ratios, inconsistent or sparse communication, and the absence of protocols for prolonged mass casualty events.^{7,12,24,31,34-36,39,41}  Additionally, the issue of uncertainty about infection risk for HCPs, patient prognosis, and time to peak infections added to nursing distress.^24,33  Environmental challenges also included spillover of ICU patients to units not intended for prolonged care of critically ill patients.³²  The added burden of PPE involving multistep donning and doffing, with concerns about inadvertent exposure and long hours in PPE, contributed to stress for nurses.^{7,30,32,34,35} 

In response to the pandemic, nurses’ role had to rapidly evolve, with increased workload, involuntary redeployment to unfamiliar environments, resource limitations that affected quality of care, and high patient volumes.³²  High patient volume was addressed with the rapid redeployment of non-ICU staff. This practice required ICU nursing staff to rapidly assume new responsibilities, including team leadership, in-the-moment training, and support of redeployed staff members.^7,23,30  The high volume of patients with complex nursing needs resulted in many redeployed nurses feeling unprepared to care for their patients.^7,23,30 

Nurses frequently reported physical and psychological harm due to the pandemic.^{12,16,19,20,36,39}  Participants across studies reported stress related to risk of infection,^{7,24,30,34,35}  with additional fear of infecting family members or having to witness family members or colleagues become seriously ill or die.^7,31-33  Many nurses witnessed suffering that they had not been previously exposed to.^20,35 

Lack of frontline support from administrators and managers contributed to frustration and feelings of being disrespected.^7,20,34  Some nurses felt that they were disproportionately placed at risk compared with other HCPs as a result of prolonged exposure to infected patients and unavailability or restricted use of PPE.²⁰ 

Many nurses reported distress from being unable to meet prepandemic standards of care. An example was the added barrier of PPE and the need for patient isolation, which hindered care and the establishment of therapeutic relationships with patients.^7,20,30,31  Many nurses felt that end-of-life (EOL) care was negatively affected by both visitation restrictions and PPE.^{7,24,30,31,35}  Additional stress was experienced as a result of the politicization of the pandemic and the lack of trust expressed by some community members toward HCPs.^20,32,35 

Several studies explored factors that were protective for nurses during the pandemic. Participants often reported that their colleagues were positive safeguards.^{7,10,20,31,32,35}  Improved interdisciplinary collaboration was cited as a positive outcome, specifically nurse-physician teamwork.^{19,20,30-32,35}  Leadership was seen as pivotal in providing information and maintaining morale.^{9,10,23,35,39}  Recognition of sacrifices and accomplishments contributed to feelings of appreciation for nurses.^20,30,31  Frequent education also contributed to positive feelings.^23,27,32,39 

The purpose of this scoping review was to explore the impact of the COVID-19 pandemic on nurses working in ICUs. Frontline staff members commonly experienced anxiety, depression, stress, PTSD, burnout, and physical symptoms such as sleep disturbances. Nurses were more likely to experience negative psychological impacts than members of other disciplines.^{10,11,15,18,40} 

Factors contributing to negative impacts included fear of infection,^11,24,33  inability to maintain care standards during times of pandemic surge,^{7,16,32,36,45}  uncertainty of outcomes or surge duration,^24,33  frequent organizational changes,^{7,12,24,31,33-35}  lack of PPE or PPE challenges,^{7,12,24,31,33-35}  communication challenges,^{7,12,24,31,34,35,39}  lack of support,^7,20  high workload,^55,58  required overtime,¹²  high patient volume,^55,58  and visitation restrictions.^{7,12,20,24,31,32,53}  Visitation restrictions posed new challenges and workloads, with many nurses experiencing heightened grief, distress, or other negative psychological outcomes during patient EOL.^{7,12,20,24,31,32,53} 

Concern about ICU nurse and HCP well-being is echoed in the prepandemic literature. One consensus study high-lighted that ICU HCP well-being was significantly affected by occupational stress.⁶⁰  Issues contributing to moral distress and burnout included organizational factors (resource and staffing levels, policy disorganization, administrative disengagement), frequent “high intensity” situations (EOL care, perceived futility, patient-family relationships), and negative team experiences (lack of communication, trust, respect, recognition).⁶¹  Inappropriate staffing was negatively associated with job satisfaction and intent to stay.⁶²  Intensive care unit nurses have experienced anxiety, depression, burnout, and PTSD,⁶³  with a higher incidence of PTSD symptoms among ICU versus medical or surgical nurses.⁶⁴  Situations contributing to perceived stress have included highly emotional or preventable cases, “substandard care,” and aggression from visitors.⁶⁵  The significance of previously documented psychological impacts in the current pandemic likely reflects an exacerbation of known issues that have been detrimental to nurses’ well-being in the ICU. Exploring processes that improve well-being not only will support a critical workforce in future pandemics but also may encourage healthier workplaces and worker retention outside of a pandemic.

Several risk factors for negative psychological and physical symptoms were identified. Greater work hours correlated with increased HCP anxiety and depression.¹⁴  Fewer years of work experience increased the risk of occupational stress.^16,19,37  Although some studies identified increased negative outcomes among certain age groups, there was high variability across studies.^{8,10,13,15,30,42}  Voluntary or involuntary overtime and their correlation with negative impacts are likely underreported, although they have been associated with increased risk of fatigue or burnout^66,67  and sick time before the pandemic.⁶⁸ 

Redeployed nurses experienced stress when placed in unfamiliar and high-risk critical care environments.^39,53  Distress was experienced by redeployed nurses caring for patients beyond their perceived competency or comfort owing to extreme surge pressures.^7,53  Some redeployed staff members were assigned patients independently despite previous assurances that they would provide care under the supervision of an ICU nurse.^7,53  Redeployed nurses reported distress from witnessing significant suffering and death when their usual work focused on recovery.³²  Displaced team members experienced loneliness and isolation once removed from usual unit processes and working relationships.^7,9,12  Frequent team reassignment contributed to difficulty establishing trust and role clarity.⁹ 

Many pandemic redeployment challenges reflect graduate nurse experiences of transition shock (characterized by self-doubt, anxiety, powerlessness, exhaustion, and other negative emotional states).⁶⁹  Transition into the highly technical, fast-paced ICU may exacerbate these experiences. Caring for deteriorating patients requiring rapid intervention may generate feelings of uncertainty regarding skill and competency while concurrently requiring regulation of emotional response.⁷⁰  Graduate nurses transitioning into ICUs require contextual learning, clinical exposure, and ongoing support after orientation to build confidence and competence.⁷¹  Strategies for future redeployment amid personnel shortages may include structured pairings with a dedicated ICU nurse to facilitate the establishment of trust, role clarity, and maximization of competency.⁹ 

Few studies described the models of redeployment used in the ICU or evaluated the impact of these models. The most common model was a dyad of ICU and redeployed nurses.^9,27,58  One study evaluated a tiered, dyad model of care, with nurses generally reporting positive outcomes (perceived support, respect, provision of safe care, and competency within tier).²⁷  Permanent ICU staff experienced increased workloads when faced with redeployment challenges (role clarity, high learning needs, or both),^9,23  and experienced subsequent stress.^27,36,58  Two studies found a higher prevalence of anxiety, depression, and PTSD symptoms among permanent ICU HCPs.^5,15  In a prepandemic integrative review of staff nurse preceptorship experiences, similar challenges were identified. Common themes included role ambiguity, conflict (patient vs learner needs), and overload, which contributed to preceptor workload and stress.⁷²  These challenges may be compounded during pandemic redeployment. Within this scoping review, 1 source also indicated that despite clinical expertise, ICU nurses may lack leadership skills (such as coordination of care and delegation).⁵⁸ 

Notably, those who are at risk of inequality in the workplace were more vulnerable to experiencing psychological harm. Members of minority groups scored higher for perceived stress or burnout.^13,42  The pandemic disproportionately affected members of minority groups outside of health care. People of Asian ethnicity experienced racial discrimination during the pandemic, associated with reported increases in anxiety, depressive symptoms, and sleep difficulties.⁷³ 

In terms of gender differences, men scored higher in 1 study in reports of fear of COVID-19¹¹  and had a higher risk of Maslach Burnout Inventory depersonalization,⁸  but most studies found that women experienced worse psychological and physical symptoms.^{11,15,21,37,40,42}  Gender differences have also been described in the literature among non–health care workers during the pandemic.⁷⁴  Women were more likely to experience stress with negative impact on mental well-being because of added pressure of caregiver roles outside of the workplace.⁷⁴ 

Despite the negative impact of the pandemic, nurses reported limited use of organizational psychological supports.^5,9,34  Nurses perceived hospital supports as inaccessible or inadequate to meet their needs.⁴⁵  Peer support was more desirable than formal counseling.⁹  Prepandemic sources also indicated that informal peer support was a commonly used coping strategy after critical incidents.^61,65,75  Intensive care unit HCPs have preferred the support of colleagues who relate to the levels of tragedy and grief in the ICU over support from family and friends.⁶¹ 

Azoulay and colleagues⁶  observed a statistically significant trend toward improved anxiety and depression, PTSD, and burnout scores for HCPs who had the ability to rest and care for their families. Reductions in depressive symptoms and work fatigue were observed when nurses were provided time off after the surge.²²  Before the pandemic, the ability to choose days off was a mitigating factor for burnout among ICU nurses.⁷⁶  Cai et al¹⁰  reported that women were more likely to experience positive impacts from stress-reducing interventions such as infection prevention safeguards, working with familiar colleagues, and limiting overtime. In addition to qualitative findings regarding education, a grey source indicated that tailored education sessions before redeployment increased HCP learner confidence and supported maintenance of care standards.⁵⁹  Further research is needed to evaluate the impact of models of nursing redeployment on psychological outcomes and to understand the conditions in which redeployment can be optimized during times of system strain.

The impact of the COVID-19 pandemic on nurses working in the ICU continues to evolve. A lack of prospective and longitudinal data limits the ability to compare the prevalence of psychological impacts within and outside of pandemic surges. Additional research is needed to determine how these impacts will evolve over the course of the pandemic and into the future. Heterogeneity of study populations, including ICU type and state of surge response, makes generalizing the findings challenging. Additionally, some studies did not differentiate outcomes between types of HCPs, which may veil nursing-specific outcomes. Although these findings signal that redeployed nurses have shared and unique stressors, future research is needed to explore specific impacts and possible protective strategies.

Nurses working in ICUs during the COVID-19 pandemic experienced negative psychological outcomes, including anxiety, depression, stress, distress, PTSD, and burnout. Further research is required to understand the impact of these outcomes over the full duration of the pandemic, among at-risk groups, and within the context of redeployment roles and surge models. Mitigation strategies should be prioritized and evaluated for future pandemic planning to reduce harm to nurses.