Agitation and Associated Factors in Critically Ill Adults
Agitation and Associated Factors in Critically Ill Adults
The study was conducted in 2010 in an 865- bed academic medical center that offers all critical care specialties. Approval was obtained from the appropriate institutional review board. The sample consisted of all adult patients 18 years and older consecutively admitted during a 2-month period to a medical respiratory ICU (MRICU) or a surgical trauma ICU (STICU). Data were obtained from medical records. Exclusion criteria were an ICU length of stay less than 24 hours (to exclude patients who had a short ICU stay for overnight monitoring), unavailability of medical records, and previous admission during the study duration. Other exclusion criteria were conditions affecting patients' movement that interfere with obtaining scores on the sedation scale, including administration of paralytic agents, neuromuscular disorders (eg, cerebral palsy and Parkinson disease), and head trauma or stroke.
Agitation was identified on the basis of documented scores on the Richmond Agitation-Sedation Scale (RASS), a 10-point scale from +4 (combative) to -5 (unarousable). The RASS has excellent interrater reliability and criterion, construct, and face validity across a variety of critical care settings. RASS scores are routinely obtained every 4 hours in the ICUs and more frequently if needed. Scores of +1 (restless) through +4 (combative) were considered indicative of agitation. The +1 score was accepted because positive RASS scores have been previously documented as indications of agitation. Agitation was also documented by using the keyword agitation (all forms of the word: agitated, agitation, agit) recorded from the medical record by using physicians' and nurses' notes in the nursing bedside flow sheet, emergency department documentation, operating room notes, and circle-theitem for reporting agitation in flow sheets.
Patients' medical records were used as the primary source of information, and data were collected by 1 investigator (R.S.B.). A pilot study was performed with patients who were not part of the study cohort. Data audits were performed to verify accuracy of information by using convenience sampling on approximately 10% of all patients. The error rate on the data audit was less than 0.03%.
The goal was to obtain an equal number of patients in each unit that would span most of the 2- month period, allowing for a broad representation of unit admissions. Data were collected on the first 5 days of ICU stay, because onset and duration of agitation are 3 to 5 days.
For all recurrent data collection, the hour was used as the documentation epoch. Each individual hour was documented as an agitation hour only if the RASS score was +1 or greater or the word agitation (and/or its forms) was documented during that hour. Patient demographics were recorded (age, sex, ethnicity, race); source of admission (clinic, emergency department, home, long-term care facility, other hospital); admission diagnosis; intubation status; scores obtained at the time of ICU admission for Acute Physiology and Chronic Health Evaluation III, Sequential Organ Failure Assessment, and Charlson Comorbidity Index; ICU and hospital lengths of stay; and administration of analgesics and sedatives.
Data were summarized by hour, block (block = 4 hours), and day for each patient and categorized as an agitation or a nonagitation hour, block, or day. Hourly data were condensed into blocks because the standard ICU flow sheet contained 4-hour blocks with agitation available as an item to circle. The consolidation of hourly data into blocks reduced documentation redundancy error while smoothing data peaks. If any agitation was documented within the hour, block, or day, or multiple episodes of agitation were documented during the time period, the occurrence of agitation was considered to be 1 agitation hour, block, or day. Additional data collection included time, ICU day, day of the week, all RASS scores, and descriptors of agitated behavior. The percentages of agitation hours, blocks, and days were based on the number of hours, blocks, and days divided by the total number of observed hours, blocks, and days throughout the 5-day period; these varied according to the patient's duration of ICU stay. Agitation reported as any time included documentation of any agitation at any time during the study period. For data on the onset of agitation, only the first agitation event for hour, block, or day for each patient during the study period was evaluated. For investigation of the temporal patterns of agitation, all agitation hours and blocks were grouped by day of the week, day and night intervals, and time of day.
Descriptive data were expressed as counts and percentages for all nominal and categorical data, and mean, range, and standard deviation for continuous measures. The significance level was α= .05. Univariate analyses were used to compare the 2 groups of patients (nonagitated and agitated) by using χ analysis and the Fisher exact test for categorical data and 2-sample t tests for continuous data.
Methods
Patients and Setting
The study was conducted in 2010 in an 865- bed academic medical center that offers all critical care specialties. Approval was obtained from the appropriate institutional review board. The sample consisted of all adult patients 18 years and older consecutively admitted during a 2-month period to a medical respiratory ICU (MRICU) or a surgical trauma ICU (STICU). Data were obtained from medical records. Exclusion criteria were an ICU length of stay less than 24 hours (to exclude patients who had a short ICU stay for overnight monitoring), unavailability of medical records, and previous admission during the study duration. Other exclusion criteria were conditions affecting patients' movement that interfere with obtaining scores on the sedation scale, including administration of paralytic agents, neuromuscular disorders (eg, cerebral palsy and Parkinson disease), and head trauma or stroke.
Documentation of Agitation
Agitation was identified on the basis of documented scores on the Richmond Agitation-Sedation Scale (RASS), a 10-point scale from +4 (combative) to -5 (unarousable). The RASS has excellent interrater reliability and criterion, construct, and face validity across a variety of critical care settings. RASS scores are routinely obtained every 4 hours in the ICUs and more frequently if needed. Scores of +1 (restless) through +4 (combative) were considered indicative of agitation. The +1 score was accepted because positive RASS scores have been previously documented as indications of agitation. Agitation was also documented by using the keyword agitation (all forms of the word: agitated, agitation, agit) recorded from the medical record by using physicians' and nurses' notes in the nursing bedside flow sheet, emergency department documentation, operating room notes, and circle-theitem for reporting agitation in flow sheets.
Procedure
Patients' medical records were used as the primary source of information, and data were collected by 1 investigator (R.S.B.). A pilot study was performed with patients who were not part of the study cohort. Data audits were performed to verify accuracy of information by using convenience sampling on approximately 10% of all patients. The error rate on the data audit was less than 0.03%.
The goal was to obtain an equal number of patients in each unit that would span most of the 2- month period, allowing for a broad representation of unit admissions. Data were collected on the first 5 days of ICU stay, because onset and duration of agitation are 3 to 5 days.
For all recurrent data collection, the hour was used as the documentation epoch. Each individual hour was documented as an agitation hour only if the RASS score was +1 or greater or the word agitation (and/or its forms) was documented during that hour. Patient demographics were recorded (age, sex, ethnicity, race); source of admission (clinic, emergency department, home, long-term care facility, other hospital); admission diagnosis; intubation status; scores obtained at the time of ICU admission for Acute Physiology and Chronic Health Evaluation III, Sequential Organ Failure Assessment, and Charlson Comorbidity Index; ICU and hospital lengths of stay; and administration of analgesics and sedatives.
Data Analysis
Data were summarized by hour, block (block = 4 hours), and day for each patient and categorized as an agitation or a nonagitation hour, block, or day. Hourly data were condensed into blocks because the standard ICU flow sheet contained 4-hour blocks with agitation available as an item to circle. The consolidation of hourly data into blocks reduced documentation redundancy error while smoothing data peaks. If any agitation was documented within the hour, block, or day, or multiple episodes of agitation were documented during the time period, the occurrence of agitation was considered to be 1 agitation hour, block, or day. Additional data collection included time, ICU day, day of the week, all RASS scores, and descriptors of agitated behavior. The percentages of agitation hours, blocks, and days were based on the number of hours, blocks, and days divided by the total number of observed hours, blocks, and days throughout the 5-day period; these varied according to the patient's duration of ICU stay. Agitation reported as any time included documentation of any agitation at any time during the study period. For data on the onset of agitation, only the first agitation event for hour, block, or day for each patient during the study period was evaluated. For investigation of the temporal patterns of agitation, all agitation hours and blocks were grouped by day of the week, day and night intervals, and time of day.
Descriptive data were expressed as counts and percentages for all nominal and categorical data, and mean, range, and standard deviation for continuous measures. The significance level was α= .05. Univariate analyses were used to compare the 2 groups of patients (nonagitated and agitated) by using χ analysis and the Fisher exact test for categorical data and 2-sample t tests for continuous data.