Open Access

Predictors of physical restraint use in Canadian intensive care units

  • Elena Luk1Email author,
  • Barbara Sneyers2,
  • Louise Rose1,
  • Marc M Perreault3,
  • David R Williamson3,
  • Sangeeta Mehta4,
  • Deborah J Cook5,
  • Stephanie C Lapinsky6 and
  • Lisa Burry4
Contributed equally
Critical Care201418:R46

DOI: 10.1186/cc13789

Received: 10 December 2013

Accepted: 7 March 2014

Published: 24 March 2014

Abstract

Introduction

Physical restraint (PR) use in the intensive care unit (ICU) has been associated with higher rates of self-extubation and prolonged ICU length of stay. Our objectives were to describe patterns and predictors of PR use.

Methods

We conducted a secondary analysis of a prospective observational study of analgosedation, antipsychotic, neuromuscular blocker, and PR practices in 51 Canadian ICUs. Data were collected prospectively for all mechanically ventilated adults admitted during a two-week period. We tested for patient, treatment, and hospital characteristics that were associated with PR use and number of days of use, using logistic and Poisson regression respectively.

Results

PR was used on 374 out of 711 (53%) patients, for a mean number of 4.1 (standard deviation (SD) 4.0) days. Treatment characteristics associated with PR were higher daily benzodiazepine dose (odds ratio (OR) 1.05, 95% confidence interval (CI) 1.00 to 1.11), higher daily opioid dose (OR 1.04, 95% CI 1.01 to 1.06), antipsychotic drugs (OR 3.09, 95% CI 1.74 to 5.48), agitation (Sedation-Agitation Scale (SAS) >4) (OR 3.73, 95% CI 1.50 to 9.29), and sedation administration method (continuous and bolus versus bolus only) (OR 3.09, 95% CI 1.74 to 5.48). Hospital characteristics associated with PR indicated patients were less likely to be restrained in ICUs from university-affiliated hospitals (OR 0.32, 95% CI 0.17 to 0.61). Mainly treatment characteristics were associated with more days of PR, including: higher daily benzodiazepine dose (incidence rate ratio (IRR) 1.07, 95% CI 1.01 to 1.13), daily sedation interruption (IRR 3.44, 95% CI 1.48 to 8.10), antipsychotic drugs (IRR 15.67, 95% CI 6.62 to 37.12), SAS <3 (IRR 2.62, 95% CI 1.08 to 6.35), and any adverse event including accidental device removal (IRR 8.27, 95% CI 2.07 to 33.08). Patient characteristics (age, gender, Acute Physiology and Chronic Health Evaluation II score, admission category, prior substance abuse, prior psychotropic medication, pre-existing psychiatric condition or dementia) were not associated with PR use or number of days used.

Conclusions

PR was used in half of the patients in these 51 ICUs. Treatment characteristics predominantly predicted PR use, as opposed to patient or hospital/ICU characteristics. Use of sedative, analgesic, and antipsychotic drugs, agitation, heavy sedation, and occurrence of an adverse event predicted PR use or number of days used.

Introduction

Physical restraint (PR) is applied in the intensive care unit (ICU) to prevent unplanned treatment interference that can lead to serious patient harm such as self-extubation. PR use in the ICU is controversial because restraints may present an ethical dilemma, conflicting with values of humane and respectful care; furthermore, PR can be perceived as barbaric, cruel, and obstructing patient autonomy [15]. PR has been linked to undesirable patient outcomes including delirium, post-traumatic stress disorder, higher rates of self-extubation, and prolonged ICU length of stay [68].

International descriptions of prevalence of physically restrained ICU patients vary from 0% to 100% across different countries [913]. Numerous policy and guideline documents aim to minimize PR practice variability and use [1418], such as Canada’s province of Ontario’s Patient Restraints Minimization Act, which legislates restraint reduction to maintain patient safety [16]. Unfortunately, few evidence-based recommendations on methods to minimize restraint use are available due to the limited number and poor quality of existing studies. Most studies describe the prevalence, and reasons and context for PR use, but do not identify modifiable predictors [913, 1922].

We conducted a secondary analysis of PR use in a large, heterogeneous sample of mechanically ventilated (MV) patients admitted to 51 Canadian ICUs [23]. Our objectives were to: (1) describe patterns of PR use in MV patients (prevalence, number of days of use, number of episodes of use); and (2) identify patient, treatment, and ICU/hospital characteristics associated with PR use and number of days of use.

Previous studies from geriatric and nursing home settings showed non-modifiable patient characteristics, such as cognitive impairment, may influence PR use [24, 25]. Therefore, we anticipated the latter might predict PR use in the ICU. As international practice recommendations are to reduce excessive sedation [26], we hypothesized that sedation practices such as type or dose of sedative-analgesic or use of sedation minimization strategies might influence PR practices. Finally, we expected organizational characteristics might be associated with PR use, as suggested by survey data [9].

Materials and methods

We conducted a secondary analysis of the I-CAN-SLEAP database. I-CAN-SLEAP was a prospective, observational study describing analgo-sedation, antipsychotic, and neuromuscular blocker administration and drug assessment or titration practices in 51 Canadian ICUs [23]. ICUs were recruited from all 10 provinces between 2008 and 2009, representing university-affiliated and community hospitals. Patients were included in each ICU during a predefined two-week period. Patient inclusion criteria were 1) initiation of MV during the inclusion period; and 2) age ≥16 years. Data were collected from initiation of MV until extubation, 24 hours after tracheotomy, death, or for a maximum of 30 days. Each site’s Research Ethics Board (REB) approved the research protocol and waived the need for informed consent. An additional file shows a list of all REBs that approved the study (see Additional file 1).

We collected site level data on hospital and ICU characteristics including province, hospital type (university-affiliated or community), number of beds (hospital and ICU), ICU type (for example, medical, surgical), physician model (open or closed; closed defined as patient care led by the ICU team), proportion of ventilator-capable beds in the ICU, and availability of protocols and assessment scales for sedation, analgesia, and delirium. Nurse-to-patient ratio was collected on each patient daily.

We collected data on baseline patient characteristics including age, gender, Acute Physiology and Chronic Health Evaluation (APACHE) II score [27], diagnosis, comorbidities, medication history, smoking, alcohol, and prior drug use. Additional daily patient data that we characterized as treatment characteristics included: PR use (yes or no); mode of MV; doses of sedative, analgesic, antipsychotic, and neuromuscular blocking drugs; presence of organ failure; mode of sedation administration (intermittent use vs. continuous infusion vs. both); daily sedation interruption (DSI); use of sedation protocols; use of sedation, pain and delirium assessment scales; and adverse events defined as deliberate or accidental device removal (endotracheal tube, intravenous catheter, feeding tube and urinary catheter) by patients or accidental removal by staff, and danger for self or others. Doses of opioids were converted to morphine equivalents, and those of benzodiazepines to midazolam equivalents [28]. All sedation scores were converted to Sedation-Agitation Scale (SAS) scores [29] and were classified a priori as: over-sedated (SAS <3), lightly sedated (SAS 3 to 4) and agitated (SAS >4). An additional file describes scale conversions and scoring definitions in more detail (see Additional file 2).

Statistical analysis

PR prevalence was defined as PR use on at least one day during the study period. PR prevalence, demographic characteristics and clinical variables are presented as means and standard deviations (SD), and frequencies, proportions and 95% confidence intervals (CIs) for categorical variables. Demographic characteristics for ‘ever restrained’ and ‘never-restrained’ patients were compared using chi-square tests for categorical variables and Wilcoxon rank sum tests or two-sample t tests, depending on data distribution, for continuous variables.

Using multivariable logistic regression, we assessed patient, institutional and clinical factors associated with PR use at any time during the study period, and reported results using odds ratios (OR) and their associated 95% CIs. Using Poisson regression analysis, we examined associations between patient, institutional and clinical variables and the number of days of PR use, and reported incidence rate ratios (IRR) and their associated 95% CIs. Variables entered into each of the two models were selected a priori based on a review of the literature on restraint use in diverse populations. Prior to multivariable modeling, variables were assessed for multicollinearity using tolerance statistics. A tolerance value of <0.4 was used to indicate the presence of multicollinearity, which was not a concern in this analysis. The number of variables retained in the model was based on rules of modeling [30] and these rules were not violated for either logistic or Poisson model. All tests were two-tailed with a P-value ≤0.05 deemed significant. An independent statistician conducted all analyses using SAS 9.2 (SAS Institute, Cary, NC, USA).

Results

PR was used on one or more days for 374/711 patients (53%, 95% CI 49% to 56%). Patients were restrained on an average of 4.1 (SD 4.0) days, with a range of 1 to 26 days. Most patients (83%, 311/374) were restrained only once, the remainder had restraints removed and reapplied more than once during their ICU admission. Restrained and never-restrained patients had similar baseline characteristics; however, differences in treatment characteristics were noted (Table 1). Restrained patients experienced more adverse events, received higher daily doses of benzodiazepines, propofol, and opioids, received more days of antipsychotics, experienced DSI more frequently, and were agitated (SAS >4) and over-sedated (SAS <3) on more days.
Table 1

Characteristics of patients who were restrained and never restrained

Data point a

Non-restrained (n = 337)

Restrained (n = 374)

Patient characteristics

  

Age (years)

60.6 (16.6)

61.1 (16.8)

Gender (male)

212 (63)

230 (62)

APACHE II score

19.9 (8.0)

19.4 (7.7)

Patient admission category

  

  Medical

124 (37)

156 (42)

  Surgical

115 (34)

132 (35)

  Cardiac

52 (15)

33 (9)

  Neurologic/trauma

35 (10)

41 (11)

  Other

11 (3)

12 (3)

Duration of organ dysfunction (days)

  

  Renal failure b

0.9 (2.4)

1.4 (3.3)

  Hepatic failure c

0.4 (1.6)

1.0 (3.2)

Inotrope/vasopressor support (days) d

1.4 (2.0)

1.9 (3.1)

Cognitive impairment (dementia)

7 (2)

9 (2)

Psychiatric condition e

45 (13)

53 (14)

Prior use of sedative, opioid, antidepressant

113 (34)

113 (30)

Prior use of antipsychotic

25 (7)

31 (8)

Current smokers

56 (17)

68 (18)

Alcohol consumption

80 (24)

100 (27)

Habitual drug use

18 (5)

15 (4)

Treatment characteristics

  

Daily drug use

  

  Benzodiazepines (mg f )*

10.8 (34.0)

29.6 (65.8)

  Propofol (mg)*

91.1 (523.5)

104.1 (501.2)

  Opioids (mg g )*

32.9 (60.2)

64.6 (91.8)

Daily sedation interruption (days)*

0.7 (1.1)

1.2 (1.7)

Sedation-Agitation Scale scores (days)*

  

  Agitation (SAS >4) h *

0.1 (0.3)

0.4 (1.2)

  Over-sedation (SAS <3) h *

1.1 (2.1)

1.9 (2.7)

Antipsychotic administration (days)*

0.2 (0.9)

1.2 (3.0)

Duration of mechanical ventilation (days)*

3.1 (3.5)

6.8 (6.5)

Occurrence of adverse eventi*

9 (3)

24 (6)

a Values are n (%) for categorical variables and means (standard deviations) for continuous variables; b renal failure was defined as creatinine clearance <30 ml/min, serum creatinine >180 μmol/L or need for dialysis; c hepatic failure was defined as aspartate aminotransferase (AST) or alanine transaminase (ALT) >2 times the upper limit of normal or bilirubin >3 times the upper limit of normal; d inotrope or vasopressor support: administration of inotropes and vasopressors at any dose; e psychiatric condition included depression, anxiety, bipolar disorder, schizophrenia; f dose expressed in midazolam equivalents (1 mg midazolam = 0.5 mg lorazepam); g dose expressed in morphine equivalents (10 mg morphine = 2 mg hydromorphone = 0.1 mg fentanyl); h Sedation-Agitation Scale; i adverse events comprised deliberate or accidental device removal (endotracheal tube, intravenous lines, feeding tubes, urinary catheters) by patients or accidental removal by staff, and danger to self or others. *Difference between groups was statistically significant (P <0.05). APACHE II, Acute Physiology and Chronic Health Evaluation II.

PR was used on an average of 76% (95% CI 66% to 85%) of days the patients’ SAS was >4; and 58% (95% CI 51% to 65%) of days the patients’ SAS was <3. PR was used on an average of 42% (95% CI 34% to 50%) of days with DSI, 65% (95% CI 55% to 75%) of days an antipsychotic was prescribed, and 61% (95% CI 45% to 76%) of days an adverse event occurred.

Treatment variables independently associated with PR use comprised: higher benzodiazepine and opioid daily doses, sedation administration method (continuous and bolus vs. bolus only), ever receiving an antipsychotic, and ever scoring SAS >4 (Table 2). For every 10 mg increment in morphine-equivalent dose and for every 10 mg increment in midazolam-equivalent dose, the risk of PR increased by 4% and 5% respectively. PR use was less likely in university-affiliated hospitals. Patients were more likely to be restrained when the ICU proportion of ventilator-capable beds was >50% and ≤90% as compared to when the ICU proportion of ventilator-capable beds was <25%. Variables independently associated with more days of PR use included higher daily benzodiazepine dose, DSI, ever receiving an antipsychotic, SAS <3 and occurrence of an adverse event (Table 3). Patients were more likely to be restrained for more days in ICUs where proportion of ventilator-capable beds was 25 to 50% and 76 to 90% compared to ICUs where proportion of ventilator-capable beds was <25%.
Table 2

Factors independently associated with physical restraint use

Data point

Univariable

Multivariable

 

OR a (95% CI)

OR a (95% CI)

Patient characteristics

  

Age

1.00 (0.99-1.01)

1.00 (0.99-1.01)

Male sex

0.98 (0.71-1.33)

1.15 (0.78-1.69)

Psychiatric condition b

1.02 (0.66-1.56)

0.86 (0.48-1.55)

Cognitive impairment (dementia)

1.01 (0.36-2.81)

1.42 (0.40-5.00)

Prior psychotropic drug use c

0.91 (0.67-1.24)

0.98 (0.64-1.50)

Smoking or alcohol consumption, habitual drug use

0.99 (0.73-1.36)

1.03 (0.70-1.53)

Patient category

  

  Surgical

1

1

  Medical

0.93 (0.66-1.32)

0.96 (0.60-1.52)

  Other

0.75 (0.51-1.11)

0.96 (0.58-1.59)

APACHE II score

0.99 (0.97-1.01)

1.00 (0.97-1.02)

Treatment characteristics

  

Medication use per mechanical ventilation days

  

  Benzodiazepines (10 mg increments d )

1.11 (1.06-1.16)

1.05 (1.00-1.11)

  Propofol (10 mg increments)

1.00 (1.00-1.00)

1.00 (1.00-1.00)

  Opioids (10 mg increments e )

1.06 (1.04-1.09)

1.04 (1.01-1.06)

Daily sedation interruption

1.36 (1.00-1.84)

1.46 (0.93-2.30)

Sedation administration

  

  Intermittent use only

1

1

  Continuous infusion only

1.43 (0.93-2.21)

1.39 (0.74-2.59)

  Both

4.14 (2.45-7.01)

2.71 (1.35-5.43)

Antipsychotic prescription

4.07 (2.50-6.64)

3.09 (1.74-5.48)

Sedation-Agitation Scale scores

  

  Agitation (SAS >4) f

7.31 (3.27-16.36)

3.73 (1.50-9.29)

  Over-sedation (SAS <3) f

2.74 (1.83-4.08)

1.30 (0.77-2.20)

Adverse event g

2.44 (1.12-5.34)

1.29 (0.53-3.15)

Hospital and ICU h characteristics

  

University-affiliated hospital (vs. community)

0.71 (0.51-0.99)

0.32 (0.17-0.61)

Closed ICU h model (vs. open model)

1.39 (0.95-2.04)

0.59 (0.34-1.04)

Proportion of ventilator capable beds in the ICU h

  

  <25%

1

1

  25-50%

0.55 (0.25-1.21)

0.99 (0.34-2.85)

  51-75%

1.16 (0.52-2.56)

2.97 (1.03-8.55)

  76-90%

1.86 (0.83-4.15)

8.34 (2.58-26.99)

  >90%

0.63 (0.26-1.52)

1.97 (0.52-7.44)

Nurse to patient ratio ever <1:1

1.50 (1.05-2.15)

0.81 (0.51-1.30)

Province

  

  Ontario

1

1

  Newfoundland and Labrador

1.98 (1.00-3.89)

1.55 (0.64-3.77)

  Nova Scotia

0.49 (0.15-1.67)

0.37 (0.09-1.54)

  New Brunswick

/

/

  Prince Edward Island

2.96 (0.79-11.15)

4.23 (0.79-22.64)

  Quebec

1.42 (0.93-2.18)

1.80 (0.99-3.29)

  Manitoba

4.44 (1.47-13.42)

7.78 (2.13-28.46)

  Saskatchewan

0.49 (0.22-1.13)

0.46 (0.15-1.42)

  Alberta

0.87 (0.56-1.34)

1.31 (0.67-2.57)

  British Columbia

1.38 (0.43-4.45)

1.02 (0.24-4.32)

a OR, odds ratio; b psychiatric condition included documented depression, anxiety, bipolar disorder, schizophrenia; c psychotropic drugs included: sedative, narcotics, methadone, antidepressants; d dose expressed in midazolam equivalents (1 mg midazolam = 0.5 mg lorazepam); e dose expressed in morphine equivalents (10 mg morphine = 2 mg hydromorphone = 0.1 mg fentanyl); f Sedation-Agitation Scale; g adverse events comprised deliberate or accidental device removal (endotracheal tube, intravenous lines, feeding tubes, urinary catheters) by patients or accidental removal by staff, and danger to self or others; h ICU, intensive care unit; /, low frequency counts did not allow for more accurate estimates. APACHE II, Acute Physiology and Chronic Health Evaluation II.

Table 3

Factors independently associated with number of days of physical restraints

Data point

Univariable

Multivariable

 

IRR a (95% CI)

IRR a (95% CI)

Patient characteristics

  

Age

1.01 (0.99-1.04)

1.00 (0.98-1.03)

Male sex

0.87 (0.37-2.06)

0.73 (0.35-1.54)

Psychiatric condition b

1.13 (0.35-3.67)

1.27 (0.42-3.84)

Cognitive impairment (dementia)

0.17 (0.01-2.86)

0.28 (0.02-3.40)

Prior psychotropic drug use c

0.60 (0.26-1.41)

0.45 (0.19-1.06)

Smoking or alcohol consumption, habitual drug use

1.68 (0.71-3.98)

1.55 (0.73-3.27)

Patient category

  

  Surgical

1

1

  Medical

1.48 (0.58-3.78)

1.74 (0.72-4.22)

  Other

0.58 (0.19-1.72)

0.61 (0.24-1.56)

APACHE II score

0.97 (0.92-1.02)

0.97 (0.92-1.02)

Treatment characteristics

  

Medication use per mechanical ventilation days

  

  Benzodiazepines (10 mg increments d )

1.11 (1.05-1.17)

1.07 (1.01-1.13)

  Propofol (10 mg increments)

1.00 (1.00-1.01)

0.99 (0.99-1.00)

  Opioids (10 mg increments e )

1.05 (1.00-1.01)

1.00 (0.99-1.10)

Daily sedation interruption

9.64 (4.23-21.94)

3.44 (1.46-8.10)

Sedation administration

  

  Intermittent use only

1

1

  Continuous infusion only

3.35 (0.93-12.16)

0.87 (0.23-3.22)

  Both

23.47 (5.97-92.27)

3.50 (0.88-13.89)

Antipsychotic prescription

45.10 (18.56-109.62)

15.67 (6.62-37.12)

Sedation-Agitation Scale scores

  

  Agitation (SAS >4) f

13.19 (4.12-42.15)

1.99 (0.63-6.27)

  Over-sedation (SAS <3) f

11.04 (4.56-26.70)

2.62 (1.08-6.35)

Adverse event g

20.45 (3.98-105.14)

8.27 (2.07-33.08)

Hospital and ICU h characteristics

  

University-affiliated hospital (vs. community)

1.51 (0.63-3.61)

0.46 (0.15-1.43)

Closed ICU h model (vs. open model)

4.06 (1.34-12.26)

0.86 (0.25-3.00)

Proportion of ventilator capable beds in the ICU h

  

  <25%

1

1

  25-50%

7.75 (0.87-69.27)

15.82 (1.65-151.84)

  51-75%

1.97 (0.23-16.68)

5.99 (0.66-54.01)

  76-90%

7.66 (0.92-63.51)

31.76 (3.02-334.41)

  >90%

1.90 (0.16-22.47)

10.31 (0.67-157.93)

Nurse to patient ratio ever <1:1

2.73 (1.08-6.89)

1.75 (0.75-4.13)

Province

  

  Ontario

1

1

  Newfoundland and Labrador

3.63 (0.35-38.16)

3.59 (0.34-37.48)

  Nova Scotia

0.19 (0.00-14.37)

1.87 (0.04-97.96)

  New Brunswick

0.53 (0.01-39.05)

0.83 (0.01-46.75)

  Prince Edward Island

0.89 (0.04-21.49)

7.47 (0.42-133.77)

  Quebec

2.74 (0.35-21.55)

2.19 (0.31-15.38)

  Manitoba

1.40 (0.06-33.51)

8.95 (0.38-212.36)

  Saskatchewan

0.44 (0.05-3.71)

1.56 (0.17-14.82)

  Alberta

1.49 (0.05-47.70)

0.85 (0.04-20.32)

  British Columbia

1.10 (0.16-7.64)

0.93 (0.15-5.61)

a IRR, incidence rate ratio; b psychiatric condition included documented depression, anxiety, bipolar disorder, schizophrenia; c psychotropic drugs included: sedative, narcotics, methadone, antidepressants; d dose expressed in midazolam equivalents (1 mg midazolam = 0.5 mg lorazepam); e dose expressed in morphine equivalents (10 mg morphine = 2 mg hydromorphone = 0.1 mg fentanyl); f Sedation-Agitation Scale; g adverse events comprised deliberate or accidental device removal (endotracheal tube, intravenous lines, feeding tubes, urinary catheters) by patients or accidental removal by staff, and danger to self or others; h ICU, intensive care unit. APACHE II, Acute Physiology and Chronic Health Evaluation II.

Non-modifiable patient characteristics such as age, gender, APACHE II score, admission category, prior substance abuse, prior psychotropic medication, and pre-existing psychiatric condition or dementia were not associated with PR use, nor with the number of days PR was used.

Discussion

This analysis of the I-CAN-SLEAP database describes prevalence of, and variables associated with, PR use in mechanically ventilated adults. Approximately half (53%) of the patients in our study were physically restrained at least once during the study period. We found that PR use in Canadian ICUs is frequent despite provincial legislation and national accreditation standards requiring restraint minimization to maintain patient safety and provide quality health care [16, 31]. Internationally, use of PR in ICUs is highly variable with recent survey data and observational studies reporting prevalence rates between 15% and 100% [9, 12, 28, 3234]. The highest prevalence rates (for example, 90% or 100%) were found in single ICU settings [9, 32].

The most important finding in our study is that predominantly treatment factors, as opposed to patient or hospital/ICU factors, influenced the use of PR. Treatment characteristics, specifically higher daily benzodiazepine and opioid doses, use of antipsychotics, and the use of continuous infusions of analgo-sedation were predictors of PR use. Also, as we hypothesized, SAS scores >4, representing agitation, predicted PR use. We also hypothesized that sedation minimization might increase PR use for the same reasons; yet we found that higher daily opiate and benzodiazepine doses were associated with PR use. We postulate that agitated patients received more medications, in combination with PR, to manage their symptoms. Our data are comparable to previous research suggesting that benzodiazepine use is more frequent in restrained patients compared to non-PR patients [21]. Antipsychotic drugs were more frequently administered to PR patients and were associated with prolonged PR use, similarly to previous findings [21]. Patients with antipsychotic prescription have a 16-fold greater number of restraint days than those without antipsychotic prescription. As antipsychotic drugs are commonly administered for delirium, they may have been a proxy for hyperactive delirium in this study. Some reports have identified associations between PR use and delirium in the ICU; for example, PR patients were more often found to be delirious than non-PR patients [21], a greater number of patients with delirium received PR and for longer durations than patients without delirium [35], and PR use was associated with an increased risk of delirium [7].

The current trend in sedation practice is to target light sedation levels using strategies such as DSI or nurse-driven sedation titration protocols to achieve improved clinical outcomes such as reduced length of stay [26]. A recent randomized controlled trial of protocolized sedation versus protocolized sedation plus DSI, with a light target level of sedation, found no significant differences in the prevalence of PR (79.4% vs. 76.4%, P = 0.46), nor in the duration of PR use (5.36 days (6.14) vs. 4.71 days (5.67), P = 0.56) between the two groups [28]. In our study, DSI was not a predictor of PR use, but was associated with a 3.4 times increase in the number of days of PR use. Although we did not seek the reasons for restraint application, we hypothesize that agitation and treatment interference were anticipated by nurses for patients undergoing DSI, a concern which has been previously reported [36]. Similarly, in our study, agitation was associated with an increased risk of PR use. Conversely, over-sedation was associated with a longer duration of PR use, suggesting failure to discontinue PR when it may no longer be justified.

Adverse events such as self-extubation were not associated with PR use in this study, but were associated with the number of days of PR use. Several cohort studies have identified the failure to use PRs as contributing to self-extubation [3739]. However, other studies have not found PR use associated with less self-extubation. A recent systematic review of unplanned extubation in the ICU found between 25% and 87% of patients were physically restrained at time of unplanned extubation [40]. Further, one case-control study identified use of PR as associated with an increased risk of self-extubation (OR 3.1, 95% CI 1.71 to 5.70) [6]. Patients from university-affiliated hospitals were less likely to be restrained, and restrained for shorter durations. University-affiliated hospitals may use PRs less often if the clinicians working in these hospitals are more familiar with evidence-based practices or have restraint reduction protocols in place. Low nurse-patient ratios were previously described as potentially increasing PR use [9], but we found no association of PR use with nurse-patient ratio. However, this may be due to the maintenance of one-to-one nurse-patient ratios for most patient days in our study, contrasting with the heterogenous (from 1:1 to 1:4) and on average lower nurse-patient ratios reported in European centers [9].

Our study has limitations. Data collectors were not provided with a definition of PR, and as such, we cannot ascertain whether devices such as splints, intravenous arm boards, or mittens were considered as PR. PR use was recorded only once daily as a binary variable; and duration of PR use (from initiation to discontinuation) was not captured. Therefore, occurrence of more than one episode of PR in a single day was not recorded. We cannot establish the temporal relationship between risk factors and PR use. For example, future studies should aim to determine the directionality of the relationship between delirium and PR (that is, whether delirium leads to PR use or whether PR use contributes to the development of delirium) or if the relationship is bidirectional.

Additionally, we are unable to address the confounding of sedative drugs and PR. Sedatives and analgesics are used to treat agitation, anxiety, and pain in the ICU patient, but are also considered as chemical restraints, used concurrently with or alternatively to PRs. As such, future observational studies prospectively designed to explore whether use of sedative or analgesic drugs first contribute to agitation requiring use of PR or vice versa would be valuable. While we recorded the use of delirium scales, we did not record positive delirium screening. We do not know which hospitals or ICUs in our study had PR policies and protocols in place. Previous studies found that organizational or unit restraint policies and protocols may influence PR use [41, 42].

Strengths of our study include the large sample size, multicenter and national representation, and a heterogeneous sample of ICUs and patients based on broad inclusion criteria, which enhance the generalizability of our data. Furthermore, data were collected prospectively, and did not rely on retrospective chart review or clinicians’ perceptions. Finally, to our knowledge, this is the first study examining predictors of PR use and number of days of use in the ICU.

Conclusions

PR use in Canadian ICUs is common, despite legislation and guidelines to minimize use. We found that treatment characteristics specifically use of benzodiazepines, opioids, and antipsychotics, agitation, heavy sedation, sedation administration method, DSI, and occurrence of an adverse event were associated with PR use or the number of days of PR use. Understanding predictors of PR use in the ICU may increase awareness of patients at risk of receiving restraints, and enable researchers to tailor future interventions to reduce modifiable use.

Key messages

  • We found that 53% of patients in the I-CAN-SLEAP study were restrained.

  • Physical restraint use in Canadian ICUs is common despite guidelines to minimize use.

  • This study adds to the body of literature on the subject of physical restraint by examining predictors of use.

  • Treatment characteristics that influence sedation and agitation were predominantly associated with physical restraint use and number of days of use.

Notes

Abbreviations

APACHE II: 

Acute Physiology and Chronic Health Evaluation

CI: 

confidence interval

DSI: 

daily sedation interruption

ICU: 

intensive care unit

IRR: 

incidence rate ratio

MV: 

mechanically ventilated

OR: 

odds ratio

PR: 

physical restraint

SAS: 

Sedation-Agitation Scale

SD: 

standard deviation.

Declarations

Acknowledgements

We would like to address special thanks to Alex Kiss, Ph.D. for the statistical analysis. Funding for the primary study was provided by the Physicians’ Services Incorporated Foundation and the Department of Pharmacy, Mount Sinai Hospital. The secondary analysis described in this manuscript was funded by the Canadian Association of Critical Care Nurses (CACCN) through a grant sponsored by the Baxter Corporation.

Authors’ Affiliations

(1)
Lawrence S. Bloomberg Faculty of Nursing, University of Toronto
(2)
Louvain Drug Research Institute, Université catholique de Louvain
(3)
Faculté de pharmacie, Université de Montréal, CP 6128 succursale centre-ville
(4)
Mount Sinai Hospital
(5)
Departments of Medicine, Clinical Epidemiology and Biostatistics, McMaster University Health Sciences Center
(6)
Faculty of Medicine, University of Toronto, 1 King’s College Circle, Medical Sciences Building

References

  1. Evans D, Wood J, Lambert L: A review of physical restraint minimization in the acute and residential care settings. J Adv Nurs 2002, 40: 616-625. 10.1046/j.1365-2648.2002.02422.xView ArticlePubMedGoogle Scholar
  2. Reigle J: The ethics of physical restraints in critical care. AACN Clin Issues 1996, 7: 585-591. 10.1097/00044067-199611000-00014View ArticlePubMedGoogle Scholar
  3. Happ MB, Kagan SH, Strumpf NE, Evans LK, Sullivan-Marx E: Elderly patients’ memories of physical restraint use in the intensive care unit (ICU). Am J Crit Care 2001, 10: 367-369.PubMedGoogle Scholar
  4. Wunderlich RJ, Perry A, Lavin MA, Katz B: Patients’ perceptions of uncertainty and stress during weaning from mechanical ventilation. Dimens Crit Care Nurs 1999, 18: 8-12.View ArticlePubMedGoogle Scholar
  5. Larson MJ, Weaver LK, Hopkins RO: Cognitive sequelae in acute respiratory distress syndrome patients with and without recall of the intensive care unit. J Int Neuropsychol Soc 2007, 13: 595-605.PubMedGoogle Scholar
  6. Chang LY, Wang KW, Chao YF: Influence of physical restraint on unplanned extubation of adult intensive care patients: a case-control study. Am J Crit Care 2008, 17: 408-415.PubMedGoogle Scholar
  7. Van Rompaey B, Elseviers MM, Schuurmans MJ, Shortridge-Baggett LM, Truijen S, Bossaert L: Risk factors for delirium in intensive care patients: a prospective cohort study. Crit Care 2009, 13: R77. 10.1186/cc7892PubMed CentralView ArticlePubMedGoogle Scholar
  8. Jones C, Bäckman C, Capuzzo M, Flaatten H, Rylander C, Griffiths RD: Precipitants of post-traumatic stress disorder following intensive care: a hypothesis generating study of diversity in care. Intensive Care Med 2007, 33: 978-985. 10.1007/s00134-007-0600-8View ArticlePubMedGoogle Scholar
  9. Benbenbishty J, Adam S, Endacott R: Physical restraint use in intensive care units across Europe: the PRICE study. Intensive Crit Care Nurs 2010, 26: 241-245. 10.1016/j.iccn.2010.08.003View ArticlePubMedGoogle Scholar
  10. De Jonghe B, Constantin J, Chanques G, Capdevila X, Lefrant J, Outin H, Mantz J, Group Interfaces Sédation: Physical restraint in mechanically ventilated ICU patients: a survey of French practice. Intensive Care Med 2013, 39: 31-37. 10.1007/s00134-012-2715-9View ArticlePubMedGoogle Scholar
  11. Martin B, Mathisen L: Use of physical restraints in adult critical care: a bicultural study. Am J Crit Care 2005, 14: 133-142.PubMedGoogle Scholar
  12. Langley G, Schmollgruber S, Egan A: Restraints in intensive care units─a mixed method study. Intensive Crit Care Nurs 2011, 27: 67-75. 10.1016/j.iccn.2010.12.001View ArticlePubMedGoogle Scholar
  13. Choi E, Song M: Physical restraint use in a Korean ICU. J Clin Nurs 2003, 12: 651-659. 10.1046/j.1365-2702.2003.00789.xView ArticlePubMedGoogle Scholar
  14. Maccioli GA, Dorman T, Brown BR, Mazuski JE, McLean BA, Kuszaj JM, Rosenbaum SH, Frankel LR, Devlin JW, Govert JA, Smith B, Peruzzi WT, American College of Critical Care Medicine; Society of Critical Care Medicine: Clinical practice guidelines for the maintenance of patient physical safety in the intensive care unit: use of restraining therapies─American College of Critical Care Medicine Task Force 2001–2002. Crit Care Med 2003, 31: 2665-2676. 10.1097/01.CCM.0000095463.72353.ADView ArticlePubMedGoogle Scholar
  15. Bray K, Hill K, Robson W, Leaver G, Walker N, O’Leary M, Delaney T, Walsh D, Gager M, Waterhouse C, British Association of Critical Care Nurses: British Association of Critical Care Nurses position statement on the use of restraint in adult critical care units. Nurs Crit Care 2004, 9: 199-212. 10.1111/j.1362-1017.2004.00074.xView ArticlePubMedGoogle Scholar
  16. Government of Ontario: Patient Restraints Minimization Act. 2001.http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_01p16_e.htm []Google Scholar
  17. College of Nurses of Ontario: Restraints. 2009.http://www.cno.org/Global/docs/prac/41043_Restraints.pdf []Google Scholar
  18. Registered Nurses of Ontario: Promoting Safety: Alternative Approaches to the Use of Restraints. 2012.http://rnao.ca/bpg/guidelines/promoting-safety-alternative-approaches-use-restraints []Google Scholar
  19. Turgay AS, Sari D, Genc RE: Physical restraint use in Turkish intensive care units. Clin Nurse Spec 2009, 23: 68-72. 10.1097/NUR.0b013e318199125cView ArticlePubMedGoogle Scholar
  20. Minnick AF, Leipzig RM, Johnson ME: Elderly patients’ reports of physical restraint experiences in intensive care units. Am J Crit Care 2001, 10: 168-171.PubMedGoogle Scholar
  21. Raijmakers RJ, Vroegop RL, van den Boogaard M, van der Kooil AW, Slooter AJ: Use of physical restraint in Dutch intensive care units: prevalence and motives [abstract]. Intensive Care Med 2012, 38: A0850.Google Scholar
  22. Kandeel NA, Attia AK: Physical restraints practice in adult intensive care units in Egypt. Nurs Health Sci 2013, 15: 79-85. 10.1111/nhs.12000View ArticlePubMedGoogle Scholar
  23. Burry L, Perreault M, Williamson D, Cook D, Wong Z, Rodrigues H, Hallett D, Ethier C, Markel S, Quittnat F, Ferguson MD, Mehta S: A prospective evaluation of sedative, analgesic, anti-psychotic and paralytic practices in Canadian mechanically ventilated adults [abstract]. Am J Respir 2009, 179: A5492.Google Scholar
  24. Karlsson S, Bucht G, Eriksoon S, Sandman PO: Factors relating to the use of physical restraint in geriatric care settings. J Am Geriatr Soc 2001, 49: 1722-1728. 10.1046/j.1532-5415.2001.49286.xView ArticlePubMedGoogle Scholar
  25. Sullivan-Marx E, Strumpf NE, Evans LK, Baumgarten M, Maislin G: Predictors of continued physical restraint use in nursing home residents following restraint reduction efforts. J Am Geriatr Soc 1999, 47: 342-348.View ArticlePubMedGoogle Scholar
  26. Barr J, Fraser GL, Puntillo K, Ely EW, Gelinas C, Dasta JF, Davidson JE, Devlin JW, Kress JP, Joffe AM, Coursin DB, Herr DL, Tung A, Robinson BR, Fontaine DK, Ramsay MA, Riker RR, Sessler CN, Pun B, Skrobik Y, Jaeschke R, American College of Critical Care Medicine: Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit. Crit Care Med 2013, 41: 263-306.View ArticlePubMedGoogle Scholar
  27. Knaus WA, Draper EA, Wagner DP, Zimmerman JE: APACHE II: a severity of disease classification system. Crit Care Med 1985, 13: 818-828. 10.1097/00003246-198510000-00009View ArticlePubMedGoogle Scholar
  28. Mehta S, Burry L, Cook D, Fergusson D, Steinberg M, Granton J, Herridge M, Ferguson N, Devlin J, Tanios M, Dodek P, Fowler R, Burns K, Jacka M, Olafson K, Skrobik Y, Hébert P, Sabri E, Meade M, SLEAP Investigators; Canadian Critical Care Trials Group: Daily sedation interruption in mechanically ventilated critically ill patients cared for with a sedation protocol: a randomized controlled trial. JAMA 2012, 308: 1985-1992. 10.1001/jama.2012.13872View ArticlePubMedGoogle Scholar
  29. Riker RR, Picard JT, Fraser GL: Prospective evaluation of the Sedation-Agitation Scale for adult critically ill patients. Crit Care Med 1999, 27: 1325-1329. 10.1097/00003246-199907000-00022View ArticlePubMedGoogle Scholar
  30. Harrell FE: Regression modeling strategies with applications to linear models, logistic regression and survival analysis. New York: Springer; 2001.Google Scholar
  31. Accreditation Canada 2013.http://www.accreditation.ca/en/ []
  32. Krüger C, Mayer H, Haastert B, Meyer G: Use of physical restraints in acute hospitals in Germany: a multi-centre cross-sectional study. Int J Nurs Stud 2013, 50: 1599-1606. 10.1016/j.ijnurstu.2013.05.005View ArticlePubMedGoogle Scholar
  33. Martín Iglesias V, Pontón Soriano C, Quintián Guerra MT, Velasco Sanz TR, Merino Martínez MR, Simón García MJ, González Sánchez JA: Mechanical restraint: its use in intensive cares. Enferm Intensiva 2012, 23: 164-170. 10.1016/j.enfi.2012.08.002View ArticlePubMedGoogle Scholar
  34. de Ciriza P, Amatriain AI, Nicolás Olmedo A, Goñi Viguria R, Regaira Martínez E, Margall Coscojuela MA, Asiain Erro MC: Physical restraint use in critical care units. Perceptions of patients and their families. Enferm Intensiva 2012, 23: 77-86. 10.1016/j.enfi.2011.12.004View ArticleGoogle Scholar
  35. Micek ST, Anand NJ, Laible BR, Shannon WD, Kollef MH: Delirium as detected by the CAM-ICU predicts restraint use among mechanically ventilated medical patients. Crit Care Med 2005, 33: 1260-1265. 10.1097/01.CCM.0000164540.58515.BFView ArticlePubMedGoogle Scholar
  36. Tanios MA, de Wit M, Epstein SK, Devlin JW: Perceived barriers to the use of sedation protocols and daily sedation interruption: a multidisciplinary survey. J Crit Care 2009, 24: 66-73. 10.1016/j.jcrc.2008.03.037View ArticlePubMedGoogle Scholar
  37. Tominaga GT, Rudzwick H, Scannell G, Waxman K: Decreasing unplanned extubations in the surgical intensive care unit. Am J Surg 1995, 170: 586-589. 10.1016/S0002-9610(99)80021-XView ArticlePubMedGoogle Scholar
  38. Frezza EE, Carleton GL, Valenziano CP: A quality improvement and risk management initiative for surgical ICU patients: a study of the effects of physical restraints and sedation on the incidence of self-extubation. Am J Med Qual 2000, 15: 221-225. 10.1177/106286060001500507View ArticlePubMedGoogle Scholar
  39. Carrión MI, Ayuso D, Marcos M, Paz Robles M, de la Cal MA, Alía I, Esteban A: Accidental removal of endotracheal and nasogastric tubes and intravascular catheters. Crit Care Med 2000, 28: 63-66. 10.1097/00003246-200001000-00010View ArticlePubMedGoogle Scholar
  40. da Silva PS, Fonseca MC: Unplanned endotracheal extubations in the intensive care unit: systematic review, critical appraisal, and evidence-based recommendations. Anesth Analg 2012, 114: 1003-1014. 10.1213/ANE.0b013e31824b0296View ArticlePubMedGoogle Scholar
  41. Hurlock-Chorostecki C, Kielb C: Knot-So-Fast: a learning plan to minimize patient restraint in critical care. Dynamics 2006, 17: 12-18.PubMedGoogle Scholar
  42. Kielb C, Hurlock-Chorostecki C, Sipprell D: Can minimal patient restraint be safely implemented in the intensive care unit? Dynamics 2005, 16: 16-19.PubMedGoogle Scholar

Copyright

© Luk et al.; licensee BioMed Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.