Critical Care

Upgrades to intensive care: The effects of COVID-19 on decision-making in the emergency department

a b s t r a c t

Introduction: The initial surge of critically ill patients in the COVID-19 pandemic severely disrupted processes at acute care hospitals. This study examines the frequency and causes for patients upgraded to intensive care unit (ICU) level care following admission from the emergency department (ED) to non-critical care units.

Methods: The number of ICU upgrades per month was determined, including the percentage of upgrades noted to have non-concordant diagnoses. Charts with non-concordant diagnoses were examined in detail as to the ED medical decision-making, clinical circumstances surrounding the upgrade, and presence of a diagnosis of COVID-19. For each case, a cognitive bias was assigned.

Results: The percentage of upgraded cases with non-concordant diagnoses increased from a baseline range of 14-20% to 41.3%. The majority of upgrades were due to premature closure (72.2%), anchoring (61.1%), and con- firmation bias (55.6%).

Conclusion: Consistent with the behavioral literature, this suggests that stressful ambient conditions affect cogni-

tive reasoning processes.

(C) 2021

  1. Introduction

Stress is defined medically as a physical, emotional or mental factor that causes bodily or mental tension [1]. The COVID-19 pandemic abruptly challenged healthcare with disrupted processes throughout the system. Emergency medicine (EM) physicians experienced physical stress from working long hours with personal protective gear. As the pandemic surged, they sustained mental stress from the urgency of dealing with a novel disease at a point at which diagnostics and thera- peutics were uncertain. They also encountered emotional stress from interacting with unprecedented levels of human suffering and the fears of personally contracting this dangerous, highly contagious dis- ease. EM practice may be stressful under the best of conditions, and EM physicians, by predilection, experience and training, prove them- selves capable of effective functioning in this milieu.

Empirically, it has been demonstrated that EM physicians, in frequent conditions of urgency and multitasking, may be susceptible to cognitive biases and short cuts in thinking [2]. acute stress tends to sharpen the mind by activating the fight-or-flight response that is needed to deal actively with an immediate threat [3]. Decision-making in changing and complex conditions is referred to in the

* Corresponding author at: 1011 Jones Hall, 1316 W. Ontario Street, Philadelphia, PA 19140.

E-mail address: [email protected] (K.E. Schreyer).

neurobehavioral literature as “executive function.” [4] Executive func- tion at high levels of stress may lead to rigid thinking and impulsive ac- tion, particularly in conditions of “parallel” executive function, when there are multiple stressors at play [5]. The stress of COVID-19, which was above and beyond normal stressors in EM, may have led to progres- sion past the optimum level of acute stress.

The negative effects of stress may manifest as changes in typical decision-making patterns, including that of triage of admitted patients to the floor or the intensive care unit (ICU). The percentage of upgrades of all admissions to the ICU (historically 2-5%) has been used as a quality-of-care indicator, although an imperfect one.6 Individual institu- tions have varying thresholds for ICU utilization, and the upgrade itself does not, in and of itself, signify poor quality of care. Sick patients get sicker, and most upgrades are for progression of illness.

This study focuses on unscheduled upgrades of patients to the ICU following admission from the emergency department (ED), specifically those in which the diagnosis was changed after the upgrade. Changes in diagnosis are not uncommon, because further diagnostic studies, con- sultant evaluations and response to treatments yield substantial infor- mation not available at the point of admission. The change from a tentative diagnosis made in the ED, however, may reflect an incomplete thought process behind the admission disposition. In this exploration, we attempt to determine the degree to which diagnoses of upgraded patients changed in comparison to pre-COVID-19 patterns. Using struc- tured parameters for assigning most common cognitive biases, we

0735-6757/(C) 2021

looked for possible altered patterns of decision-making that might cor- relate with pandemic-induced stress.

  1. Methods

This is a retrospective study conducted at an urban, academic, ter- tiary care center with 95,000 patient visits annually. The study site ex- perienced an abrupt influx of COVID-19 cases from March 2020 through July of 2020. There was a concomitant decrease in ED volume of 30% over that same five-month time period. Compared to the prior year, the distribution of acuity shifted toward a high acuity cohort. Dur- ing the study period, clinicians did not have access to rapid COVID-19 testing. The overall patient census declined sharply and opening of a new ICU space for Covid-19 patients prevented significant crowding and time-to-admit for non-COVID-19 patients.

We performed retrospective review of patients admitted through the ED to a non-critical level of care and then upgraded within 48 h of admission. Records were compiled by an automated process via the EPIC EMR system. A multidisciplinary ICU Committee reviews upgrades on a quarterly basis. Charts were abstracted for Early Warning Score, qSOFA score, vital sign trends and admission and discharge diagnoses. Patients with stable vital signs, low-risk, non-deteriorating EWS and qSOFA, and no change in diagnosis were considered to have been upgraded for progression of illness. Patients with high EWS or qSOFA 2 or 3, or trending deterioration of vital signs were considered as possi- ble cases of patients who might have been directly admitted to ICU. Those cases then were further evaluated individually for diagnostic con- cordance independently by a team of one senior EM attending and one EM fellow. Non-concordant diagnosis was defined as a change in pri- mary diagnosis after the upgrade that could have been effected by a change in EM management. There was a 91.9% level of agreement be- tween the two reviewers with a corresponding Cohen’s Kappa value of 0.73.

The number of ICU upgrades per month was determined, including the percentage of total upgrades noted to have non-concordant diagno- ses. Charts with non-concordant diagnoses were examined in detail as to the ED medical decision-making note and the clinical circumstances surrounding the upgrade. Charts with non-concordant diagnoses di- rectly involving COVID-19 were identified. For all cases with non- concordant diagnoses, a cognitive bias was assigned, according to de- fined criteria (Table 1). These cognitive biases were chosen because they are some of the most common in existing literature. Each member of the research team, which was comprised of three EM attending phy- sicians, one EM fellow, and one EM resident, independently evaluated each case and assigned a cognitive bias. Multiple biases were assigned if no majority was reached.

Cases were reviewed during the first peak of COVID-19 cases (March 2020-July 2020) and compared to those during the same time frame in the preceding calendar year (March 2019-July 2019). These were fur- ther compared to historical data provided by the ICU review committee. Baseline frequency of non-concordant diagnoses in ICU upgrades was calculated form aggregate data of the previous six years.

This study was granted an exemption by the IRB.

Table 1

Defined criteria of common cognitive biases evaluated. Cognitive Bias Definition

Availability Heuristic Overdiagnosis of COVID-19 in context of frequency

and severity of this disease

Anchoring Bias Diagnosis made based on a specific feature of history,

physical examination or diagnostic finding

Premature Closure Diagnosis made before all available data received that

would have been available to physician

Confirmation Bias Relevant information inconsistent with working diagnosis was discounted

  1. Results

From March 2020 through July 2020, 3981 patients were evaluated in the ED for suspected COVID-19. Of those patients, 2387 (60.0%) were admitted. The rise in COVID-19 patients was also associated with a concomitant 21.1% decrease in ED volume over the same time period, from 41,433 visits in 2019, to 32,706 visits in 2020. Compared to 2019, 4% more patients were categorized as ESI level I and II, while 4% less were categorized as ESI levels IV and V. The percentage of ESI III patients remained constant from 2019 to 2020.

A total of 24 cases were reviewed and assigned biases, as summa- rized in Table 2. The increase in the overall number of ICU upgrades in 2019 and 2020 during our study period did not reach statistical signifi- cance when using a one-sided Mann-Whitney two sample test (U = 10, p = 0.337) (Table 3). In the 2020 study period, 19 out of 46 ICU up- grades (41.3%) were associated with non-concordant diagnoses. Only five of these cases were associated with a COVID-19 diagnosis. In com- parison, for the same months in 2019, only six out of 54 upgrades (11.1%) demonstrated non-concordant diagnoses. This increase in up- grades due to non-concordant diagnoses did reach statistical signifi- cance (U = 3.5 p = 0.038). Aggregate data from the previous six years (2013-2018) showed 14% of upgrades with non-concordant diagnoses.

Premature closure was the most prominent cognitive bias, present in 72.2% of ICU upgrades due to non-concordant diagnoses in 2020, compared to only 50% of ICU upgrades in 2019. Anchoring was the most prominent non-concordant diagnosis in 2019, in 66.7% of cases. In 2020, it was present in 61.1% of cases. The prevalence of confirmation bias also increased in 2020 (55.6%), compared to 2019 (33.3%). Avail- ability heuristic was least present in both years (Table 4).

  1. Discussion

A small body of literature addresses patterns and predictors of pa- tients upgraded to an ICU within 24-48 h following admission from the ED to a non-critical level of care [6]. Reasons for such upgrades have been characterized as progression of illness, mistriage (i.e., those that would have been appropriate for ICU admission initially), non- concordant diagnosis, and new events occurring after admission [7].

Review of all ICU upgrades for a 5-year period from this busy hospi- tal showed 355 such patients (1.3% of all admissions). Prior to COVID- 19, non-concordant diagnosis, in which the admission diagnosis dif- fered from primary diagnosis at point of upgrade, or at hospital dis- charge, was the etiology in 20.1% of all upgrades. In contrast, during the 4-month period beginning March 2020 at the outset of the COVID- 19 pandemic, non-concordant diagnosis-related ICU upgrades were found to be 41.3%. This unexpected finding prompted focused review of the same 4-month period in 2019, which found 14.3% non- concordant diagnosis during the matched period. Though the number of patients was small, it was significantly different, and it was in marked contrast to what had been consistent findings on prior monthly review. This raised the question of whether or not the pandemic was associated with changed patterns of medical decision-making.

Croskerry has described the ED as a “natural laboratory for error.” [8] Ambient conditions of unpredictability, multitasking, interruptions and high-risk decision-making, in context of time and data constraints, rep- resent a typical work day. As Croskerry points out, the EM physician may make thousands of decisions in a single shift, a density of decision-making greater than any other specialty, possibly greater than that of any other profession. A commentary by Pines suggests that increased ED crowding, resulting in a higher percentage of admis- sions, might imply less analytic effort in context of patient overload [9]. Greater load of decision-making, that is, may trigger increased use of cognitive short cuts. Neurobiological studies suggest that acute stress affects cognition through activation of the adrenergic axis, whereas on- going stress tends to involve cortisol levels, with less beneficial effect on

Table 2

ICU upgrades due to non-concordant diagnoses and cognitive biases.

Table 3

Intensive care unit (ICU) upgrades due to non-concordant diagnoses.

ED diagnosis

ICU Upgrade Diagnosis

Cognitive Biases

Total ICU* Upgrades

Upgrades due to non-concordant

Non-concordant diagnoses

March 2019 – June 2019 diagnoses including COVID-19

AKI, Hyperchloremic Acidosis, Respiratory Failure, atrial flutter, A, PC 2019

Dehydration, Chemotherapy

Tumor lysis syndrome





Adverse Reaction, Hypoxia





Chest Pain

Hypoxic Respiratory Failure,






Cardiac Arrest, Multifocal





Pneumonia, Mucous Plug, Sepsis





Lumbar Transverse Process Fracture, cocaine intoxication, Trauma

Cardiac syncope, Ventricular A Bigeminy, Ventricular



Pyogenic Arthritis of Right Knee Pseudogout, Hyperkalemia,

Sepsis, Pneumonia

Intractable Headache Hyponatremia, Pituitary Hemorrhage, Benign Neoplasm of Pituitary Gland

Spontaneous bacterial peritonitis Uremic Encephalopathy, Urinary

Tract Infection, Septic Shock

March 2020 – June 2020

Symptomatic Anemia esophageal varices with Acute Hemorrhage,

COPD exacerbation, Hypotension Lobar Pneumonia, Severe Sepsis,

CHF Exacerbation





ICU upgrades due to non-concordant diagnoses, and non-concordant diagnoses involving COVID-19 are reported, for March-July 2019 and March-July 2020. Two sample Mann- Whitney test: ICU upgrades2020 > ICU upgrades2019. ICU = intensive care unit. * indicates statistical significance.





















Mann-Whiteney Test:

U statistic






Cellulitis of Left Lower Leg Septic Shock AH, CB, PC

Lung Mass, failure to thrive Cerebral Edema, Secondary

Malignant Neoplasm of Brain


frequency cannot be ascribed to increased patient load, as the number of treated patients decreased by more than 30% during this 4-month in-

COPD Exacerbation, Hypoxia,

Elevated Troponin, Atrial Fibrillation

Encephalopathy, Elevated Troponin, Alcoholic Hepatitis

Hypoxic and Hypercapnic

Respiratory Failure, Urosepsis

Ventricular Fibrillation, Cardiac Arrest, UTI, Sepsis, Rhabdomyolysis, NSTEMI



terval. With COVID-19 on the forefront of everyone’s minds, anchoring and availability bias were likely at play. However, there was less overdi- agnosis of COVID-19 than might have been expected. Confirmation bias, in which findings inconsistent with the presumptive diagnosis were ig-

nored, was seen as well, and notably more than in the previous year.

acute pulmonary edema Influenza Pneumonia, Suspected

COVID19 Pneumonia Pyelonephritis, AKI, Dyspnea Hypoxic Respiratory Failure,

Suspected COVID19 Pneumonia, suspected pulmonary embolism


Studies of stress effects on decision-making suggest tendencies toward rigid thinking, less analysis and less creativity, as perhaps might mani- fest in premature closure and confirmation bias. Previous studies have also demonstrated that premature closure is one of the most common

Acute Renal Failure, Dehydration, Fatigue, Delirium

Spontaneous Bacterial Peritonitis, Liver failure Without Coma

Acute on Chronic CHF, Suspected COVID19

COVID19 Pneumonia, Severe Sepsis with Septic Shock Hemorrhagic Shock, Esophageal Varices with Bleeding

Acute intestinal ischemia, Lactic Acidosis, AKI



causes of diagnostic error [11].

Preventing cognitive biases can be challenging. Some have advo- cated for the use of a cognitive or diagnostic “time out” to allow a phy- sician a deliberate pause to reflect on the plausibility of a working

diagnosis. This allows the clinician to ask themselves “why can’t this

Bradycardia, Hypothyroidism, Chest Pain

AKI, Syncope and Collapse, Hyponatremia

Pericardial tamponade A, CB, PC

Acute on Chronic Systolic Heart A, PC Failure, Cardiogenic Shock

be something else?” [12] Others have suggested the use of meta- cognitive strategies by educating physicians on error theory and major types of heuristics and biases. They theorize that through the process

Syncope, AKI, NSTEMI Acute Gastric Ulcer with Hemorrhage, gastric varices, Hypovolemic Shock


of metacognition, physicians can develop cognitive forcing strategies

that abort these errors [13]. Any number of these techniques can be employed to reduce the incidence and impact of cognitive biases.

Hypotension, Pre-Syncope, Atrial


Pulmonary Edema, Sepsis, Pleural

Effusion, Hypoxic Respiratory Failure


ESRD, Hypotension, CHF Septic Shock, unknown source PC

    1. Limitations

New Onset Atrial Fibrillation; Fall, Acute Ischemic Right PCA Stroke A initial encounter

Conclusions of this study are limited in that cognitive psychology

NSTEMI Saddle Embolus of Pulmonary Artery without Acute Cor Pulmonale


and neurobiology are evolving Fields of study. Studies of effects of stress on brain function have been performed either in laboratory conditions,

or longitudinally on individuals with diagnosed stress disorder. There

ED admission diagnoses and respective ICU upgrade diagnoses along with corresponding primary cognitive biases are reported for all ICU upgrades during the study period. A = Anchoring, AH = Availability Heuristic, CB = Confirmation Bias, PC = Premature Clo- sure, COPD = Chronic Obstructive Pulmonary Disease, CHF = Congestive Heart Failure, NSTEMI = Non-ST Elevation Myocardial Infarction, AKI = Acute Kidney Injury, PE = Pulmonary Embolism.

decision-making [10]. It may be that unaccustomed high levels of stress day after day challenge executive function via persistently elevated cor- tisol levels.

Decisions made without the benefit of obtainable data represent premature closure (impulsive decision-making). The abrupt increased

have not been specific studies on stress-related hormonal effects on EM physicians. This study makes the unquantifiable assumption that physician stress levels spiked during the initial months of the Covid- 19 surge. As opposed to a single stressful incident, such as a mass casu- alty disaster, stress levels persisted during the pandemic.

There are multifactorial influences on cognition, including systems issues. At this institution, early aggressive systems modifications and cooperation between ED physicians, hospitalists and intensivists, main- tained ED patient flow. However, the change in ED volumes and amount of available time and resources would have also impacted both the ED patient population and the ED physicians’ ability to respond to those pa- tients. The impact of this is also challenging to quantify.

Table 4

Prevalence of cognitive biases in intensive care unit upgrades secondary to non-concordant diagnoses.

Cognitive Bias



Number of Cases

Percentage of Cases

Number of Cases

Percentage of Cases

Premature Closure










Confirmation Bias





Availability Heuristic





Each case was reviewed and assigned most relevant cognitive biases based on pre-determined definitions. Anchoring, confirmation bias, and premature closure were present in the majority of cases, while the availability heuristic was present in only 16.7%.

While this study focuses on decision-making of ED physicians, all ad- missions were, in fact, cooperative decisions between ED and inpatient physicians. ICU upgrades involve patients with abrupt clinical deteriora- tion and momentum bias on the part of admitting physicians may have been at play. The clinical spectrum of disease differed from pre- pandemic experience, with the majority of admissions being those of COVID-19 or suspected COVID-19. In that regard, it is striking that ICU upgrades involved majority non-COVID-19 patients.

Specific cognitive biases must be assigned with caution, as there is much overlap and subjectivity in such designations. While the decision of appropriate bias to attach to each individual case of upgrade is debat- able, there seemed in this study to be a larger that previously experi- enced incidence of premature closure. However, premature closure, anchoring and confirmation bias are closely related.

A significant limitation of this study is the limited number of

upgraded patients. However, there is extensive previous tracking of ICU upgrades, and there appeared to be marked change in pattern during these initial months of COVID-19. While cognitive bias and the ambient conditions that might accentuate cognitive bias has been addressed in EM literature, knowledge and understanding are drawn from the relatively young fields of cognitive psychology and neurobiol- ogy. Studies of thinking patterns under stress have largely been per- formed under controlled laboratory conditions. We need caution in applying the tentative conclusions of these studies to the actual circum- stances of making impactful decisions in risky and rapidly changing conditions.

  1. Conclusion

Though it is early to speak of perspective gained form the COVID-19 experience, this retrospective review of ICU upgrades suggests some de- gree of changes in thought processes working within pandemic condi- tions. An atypically large percentage of upgrades were found to have change in diagnosis after admission from the ED. Furthermore, the pat- tern of those upgrades also changed in the early months of COVID-19. Cognitive biases at play seemed to trend toward premature closure, consistent with psychobiological work that has implied stress-induced tendency toward impulsive decision-making. More work remains to be done to further evaluate the relationship between the pandemic, stress, cognitive bias, and decision making.

Sources of support

The authors report no external sources of support for this study.



Declaration of Competing Interest



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