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American Journal of Critical Care. 2008;17: 349-356
Copyright © 2008 by the American Association of Critical-Care Nurses.
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Duration of Mechanical Ventilation in an Adult Intensive Care Unit After Introduction of Sedation and Pain Scales

By Teresa Ann Williams, M HlthSci PG Dip Clin Epi, BN, Suzanne Martin, BSci (Nsg), Gavin Leslie, PhD, BAppSc, Linda Thomas, BSci (Nsg), Timothy Leen, BSci (Nsg), Sheralee Tamaliunas, BSci (Nsg), K. Y. Lee, MBBS and Geoffrey Dobb, MBBS, FFICANZCA, FJFICM. Teresa Ann Williams is a nurse researcher, Suzanne Martin is a clinical nurse specialist, Linda Thomas is a research coordinator/clinical nurse, Timothy Leen is a clinical nurse specialist, Sheralee Tamaliunas is a clinical nurse specialist, and K. Y. Lee is an intensive care specialist in the intensive care unit at Royal Perth Hospital, Perth, Western Australia. Gavin Leslie is an associate professor and has a joint appointment in critical care nursing at Royal Perth Hospital and Curtin University of Technology, Perth, Australia. Geoffrey Dobb is head of the intensive care unit at Royal Perth Hospital and a clinical associate professor in the School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia.

Corresponding author: Teresa Williams, ICU, Royal Perth Hospital, Wellington St, Royal Perth Hospital, Western Australia 6000 (e-mail: teresa.williams{at}health.wa.gov.au).


   Abstract
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 Abstract
Methods
 Definitions
 Statistical Analysis
 Results
 Discussion
 Conclusion
 References
 
Background Sedation and analgesia scales promote a less-distressing experience in the intensive care unit and minimize complications for patients receiving mechanical ventilation.

Objectives To evaluate outcomes before and after introduction of scales for sedation and analgesia in a general intensive care unit.

Method A before-and-after design was used to evaluate introduction of the Richmond Agitation-Sedation Scale and the Behavioral Pain Scale for patients receiving mechanical ventilation. Data were collected for 6 months before and 6 months after training in and introduction of the scales.

Results A total of 769 patients received mechanical ventilation for at least 6 hours (369 patients before and 400 patients after implementation). Age, scores on the Acute Physiology and Chronic Health Evaluation (APACHE) II, and diagnostic groups were similar in the 2 groups, but the after group had more men than did the before group. Duration of mechanical ventilation did not change significantly after the scales were introduced (median, 24 vs 28 hours). For patients who received mechanical ventilation for 96 hours or longer (24%), mechanical ventilation lasted longer after implementation of the scales (P =.03). Length of stay in the intensive care unit was similar in the 2 groups (P = .18), but patients received sedatives for longer after implementation (P=.01). By logistic regression analysis, APACHE II score (P <.001) and diagnostic group (P <.001) were independent predictors of mechanical ventilation lasting 96 hours or longer.

Conclusion Sedation and analgesia scales did not reduce duration of ventilation in an Australian intensive care unit.

Sedation and analgesia are important components in the management of patients in intensive care units (ICUs). Adequate sedation and analgesia are essential to minimize anxiety, panic, and discomfort associated with mechanical ventilation.1–3 Use of sedation is common and is associated with longer duration of mechanical ventilation, weaning time, and stay in the ICU.4


Achieving the appropriate balance of sedation and analgesia is challenging.

 

Although ideal sedation varies from patient to patient, a common goal of sedation is to keep patients comfortable but easily rousable.5,6 This goal can be achieved by titrating the dose of the sedative agent to meet each patient’s objectives,2 which are agreed to by all caregivers to prevent different treatment goals7–9 and limit the risk of iatrogenic complications that could impede recovery.10 Achieving the appropriate balance of sedation and analgesia is challenging.11–13 If appropriately validated sedation and analgesia scales are used, a consistent level of sedation is more likely to be achieved, promoting patients’ comfort, facilitating a less-distressing ICU experience, and minimizing the duration of ventilatory support.14–17 The aim of this study was to evaluate patient-related outcomes before and after the introduction of a sedation scale and an analgesia scale; the primary outcome measure was duration of mechanical ventilation.


   Methods
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 Methods
Definitions
 Statistical Analysis
 Results
 Discussion
 Conclusion
 References
 
The study was conducted in a 22-bed adult general ICU. The ICU is a tertiary level III18 closed unit in Royal Perth Hospital, Western Australia, a metropolitan teaching hospital with 855 beds. All patients who received at least 6 hours of mechanical ventilation in the ICU were included. Patients were excluded from the study if they were not intubated, received mechanical ventilation for fewer than 6 hours, or died in the ICU.

Morphine and midazolam (usually given in a single syringe) or propofol infusions were the most frequently administered analgesic and sedative agents. No formal method of titration and monitoring of sedation was used before the introduction of the sedation and analgesia scales, and the decision to increase or decrease the level of sedatives administered to patients was most often left to the discretion of the bedside nurse. No daily interruption of sedation was used.

The Richmond Agitation-Sedation Scale (RASS)19 and the Behavioral Pain Scale (BPS)20 were selected to assess patients’ sedation and analgesia. These tools were selected on the basis of a consensus of expert clinicians (nurses and intensivists) working in the ICU. The RASS has been tested for reliability and validity19 and has been used in ICU studies.10,21 The BPS also has been tested for reliability and validity in French ICUs20 and an Australian ICU.22 The institutional ethics committee and the nursing research review committee approved the study.


   Definitions
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 Definitions
Statistical Analysis
 Results
 Discussion
 Conclusion
 References
 
Duration of mechanical ventilation was defined as the time from intubation to the time of final extubation. The time of intubation was recorded as the time the endotracheal tube was inserted in the ICU, or, if the tube was inserted before the patient was admitted to the ICU (eg, in the operating room), the time of intubation was recorded as the time of admission to the ICU. Extubation time was the time of removal of the endotracheal tube, or, for patients who received a tracheostomy, the time when they began breathing spontaneously without assistance from a mechanical ventilator. Length of stay in the ICU (days) was calculated from the time of admission to the ICU to the time of discharge.

Characteristics of patients and the sedatives and analgesics received by the before group (ie, before introduction of the scales) were collected for two 3-month data collection periods. Data were collected retrospectively from patients admitted to the ICU between September 1, 2003, and November 30, 2003, and prospectively for patients admitted from December 15, 2003, to March 12, 2004. Prospectively and retrospectively collected data were compared to see if a Hawthorne effect was apparent23; that is, if administration of sedatives changed because staff members were aware that they were being observed. Education was then provided to all staff, after which the sedation and analgesia scales were introduced. A 6-week delay between the start of training and the introduction of the scales gave the staff time to become familiar with the use of the scales in clinical practice. Evaluation of patients’ outcomes after the implementation of these scales for the after group was conducted from April 25, 2004, to October 21, 2004 (6 months).

Upon introduction of the scales, patients had a predefined target RASS score, based on their condition and tolerance of mechanical ventilation, documented by medical staff on the patients’ ICU flow charts. No formal protocol was used to direct drug administration to achieve the target RASS score. Bedside nurses recorded each patient’s level of sedation and analgesia hourly (by using the RASS and BPS), along with the patient’s score on the Glasgow Coma Scale and any movement by the patient. Bedside nurses and assessors formally assessed sedation and analgesia for every patient 4 times a day. Assessors were experienced senior ICU nurses trained in the use of the RASS and the BPS. The levels of sedation and analgesia were compared with predefined treatment goals. The assessment was performed when no procedures had been undertaken and no bolus doses of sedating medications had been administered within the previous 10 minutes. The time since the last activity and the type of activity also were documented.

In an effort to minimize effects of potential confounding factors, patients were not assessed for the first 6 hours after intubation, surgery, or other procedure requiring muscle relaxants or nonroutine sedation. A research nurse reviewed ICU flow charts to determine the mode and duration of mechanical ventilation, adverse events, amount of sedatives administered, and number of boluses of sedatives.

To test interrater reliability, randomly paired assessors assessed 25 patients before introduction of the scales. A bedside nurse stimulated each patient as part of routine care, and the assessors rated the patient’s level of sedation and analgesia concurrently but independently. Neither assessor provided care for the patient under assessment during the shift to avoid bias from uneven exposure.

Ratings given for sedation and pain were compared between the trained assessors before implementation of the scales; agreement between raters was high ({kappa} statistic, 0.98). Ratings of assessors and bedside nurses also agreed (within ±1), with the measure of agreement ({kappa} statistic) at 0.96 (P < .001).

A pilot study also was conducted for the first week to determine the feasibility and appropriateness of the data collection sheet. Small adjustments were made to data collection techniques. The results from this data collection were included in study results.


The Richmond Agitation-Sedation Scale and the Behavioral Pain Scale were used.

 


   Statistical Analysis
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 Methods
 Definitions
 Statistical Analysis
Results
 Discussion
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The primary study outcome was the duration (hours) of mechanical ventilation for each admission. Secondary outcomes included the length of stay in the ICU and the number of unplanned extubations experienced by the patients in the ICU. Data collected included demographic data, worst score on the Acute Physiological and Chronic Health Evaluation (APACHE) II in the first 24 hours,24 duration of mechanical ventilation, lengths of stay in the ICU and hospital, patients’ survival from ICU and hospital, and frequency of use of sedation and analgesia.

Categorical variables were compared by using the Pearson {chi}2 test, and continuous variables were compared by using a t test for normally distributed data or nonparametric tests for nonnormally distributed data. Kaplan-Meier survival analysis was used to examine differences in duration of mechanical ventilation between groups. Logistic regression was used to test the independent effects of potential determinants, age, sex, before or after group, APACHE II score, and diagnostic group on the duration of mechanical ventilation, categorized as less than 96 hours or 96 hours and longer (short- and long-term mechanical ventilation). This time frame was chosen because it has been used before as the cutoff point to distinguish short- and long-term mechanical ventilation.25,26


Sedation and analgesia were assessed for every patient 4 times a day.

 

Variables were entered into the model by using backward elimination.27 The {kappa} statistic, a measure of agreement that corrects for agreement that occurs by chance, was used to test interrater reliability. Statistical analysis was performed with the SPSS version 14.0 computer software package (SPSS Inc, Chicago, Illinois).

All tests of significance were 2-sided, and significance levels were set at .05. A sample size of 142 patients was based on 80% power to detect a difference of 1.5 days (SD 4.5 days) in duration of mechanical ventilation between the before and after groups, {alpha}= .05 (2-tailed).28 The study was conducted for 12 months to ensure adequate recruitment and allow for patients who dropped out or were excluded.


   Results
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 Statistical Analysis
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Discussion
 Conclusion
 References
 
When the retrospective and prospective groups in the preimplementation phase were compared, neither the duration of mechanical ventilation (z=–0.8; P=.44) nor the number of days patients received sedatives (z = –0.3; P = .76) differed significantly, suggesting that no Hawthorne effect occurred, and therefore these patients were examined together as the before group. During the study period, 1343 patients were admitted to the ICU, 658 patients before and 685 patients after implementation of the sedation and pain scales (Figure 1Go). Of these admitted patients, 121 patients (9%) died in the ICU (57 patients before and 64 patients after implementation) and were excluded from the study. The study cohort consisted of 769 patients (57%) intubated for 6 hours or more (369 in the before group and 400 in the after group). Data collection was complete for all fields except those pertaining to medication received (177 of 769 patients had missing data).


Figure 1
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  		Figure 1 Patients admitted to the intensive care unit, inclusions and exclusions.

 
Table 1Go gives the characteristics of the 369 patients in the before group and the 400 patients in the after group. Ages were similar in the 2 groups, but the after group had more male patients. The mean worst APACHE II score in the first 24 hours (t =–1.26; P = .21) differed little between groups. The principal ICU admission diagnosis, coded by using the International Classification of Diseases, Ninth revision, Clinical Modification29 and grouped into 7 categories (sepsis, trauma, cardiac surgery, neurosurgery, other surgery, drug overdoses, and other medical conditions), was sixmilar for both groups ({chi}62 =12.0; P =.06). A similar number of physical restraints was used before and after the intervention (z = 0.54; P = .59; 95% confidence interval for the difference in means, –0.06 to 0.04). The incidence of unplanned extubation was less in the after group, but the difference was not significant (2 unplanned extubations after implementation vs 7 before implementation, P = .07). Other adverse events were equally distributed between the 2 groups. Median (range) length of stay in the ICU was similar in the 2 groups: 2.3 (1.2–5.7) days before implementation versus 2.6 (1.1–6.8) days after implementation (z = 1.3; P = .18).


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  		Table 1 Characteristics of patients who received mechanical ventilation: before vs after implementation of use of scalesa

 
No clinically meaningful change in duration of mechanical ventilation occurred after the scales were introduced (median 24 hours in the before group vs 28 hours in the after group; z =–1.5; P =.13). Figure 2Go shows the results of Kaplan-Meier survival analysis (truncated at 500 hours) of the duration of mechanical ventilation for both groups. Although the overall duration of mechanical ventilation was longer for the after group (log rank test = 14.1; P < .001), no difference between the 2 groups was found for patients who received mechanical ventilation for less than 24 hours (P = .34), for 24 to less than 48 hours (P =.82), for 48 to less than 72 hours (P =.13), and for 72 to less than 96 hours (P = .32). A significant difference was detected between patients in the 2 groups who received mechanical ventilation for 96 hours or longer (182 hours in the before group vs 212 hours in the after group; P = .03). When duration of mechanical ventilation of less than 96 hours was compared with duration of 96 hours and longer, important independent determinants were the APACHE II score and the ICU diagnostic group (Table 2Go). A trend toward an increased risk of longer duration of mechanical ventilation after the scales were introduced was apparent (odds ratio, 1.44; 95% confidence interval, 0.99–2.10; P = .05).


Figure 2
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  		Figure 2 Kaplan-Meier survival curve for duration of mechanical ventilation (truncated at 500 hours) before and after implementation of the use of scales.

 

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  		Table 2 Independent predictors associated with duration of mechanical ventilation (<96 hours compared with ≥96 hours) after adjustments for age, sex, worst APACHE II score in first 24 hours, diagnosis, and preimplementation or postimplementation group

 
Patients received different amounts and combinations of continuous intravenous sedatives during their stay in the ICU. Whether patients received continuous infusions of sedatives with or without analgesics, analgesics alone, or no sedatives or analgesics was recorded each day for the first 14 days of mechanical ventilation. Median age (P = .39), APACHE II score (P = .60), length of stay in the ICU (P = .25), and duration of mechanical ventilation (P = .68) were similar for both groups, but more patients in the before group did not have data on the amounts of sedatives received (39% vs 8%). For patients who had complete sedation data, the proportion of patients receiving sedatives with or without analgesics during their admission was greater in the after group (88%) than in the before group (57%; P < .001). The mean (standard deviation) number of days that patients received sedatives was 2.4 (2.3) in the before group and 3.0 (2.9) in the after group, and the median (interquartile range) was 2 (1–2) in the before group and 2 (1–3) in the after group (z = –2.7; P = .01). The 2 groups of patients did not differ in diagnostic group (P = .19), although a trend toward a difference in APACHE II scores (P = .05) was noted among patients receiving sedatives before and after implementation of the scales. The most commonly administered infusions in both groups were morphine and/or midazolam or propofol.


   Discussion
Top
 Abstract
 Methods
 Definitions
 Statistical Analysis
 Results
 Discussion
Conclusion
 References
 
The effect of the introduction of the RASS and the BPS, used to facilitate assessment and management of sedation in the ICU, on duration of mechanical ventilation was examined for 769 patients admitted to the ICU. We hypothesized that the introduction and use of these scales would result in a decrease in duration of mechanical ventilation and ICU length of stay.14,19 A before-and-after study design was used because it was not feasible to conduct a randomized controlled trial and ensure elimination of intervention bias between patients. The difference between groups in the median duration of mechanical ventilation (4 hours) was not clinically significant, and no difference was found when periods of mechanical ventilation less than 24 hours, 24 to less than 48 hours, 48 to less than 72 hours, and 72 to less than 96 hours were compared.


Duration of mechanical ventilation did not change after the scales were introduced.

 

A difference was found between patients who did and did not have mechanical ventilation for 96 hours or longer (mechanical ventilation ≥96 hours: before group, 78 patients; after group, 104 patients). Age, sex, APACHE II score before and after intervention, and diagnostic group were important in univariate analysis, but not comorbid diseases, estimated on the basis of the chronic health evaluation points. Admission diagnosis and the APACHE II score contributed significantly to the duration of mechanical ventilation (<96 hours or ≥96 hours) after adjustment for confounders in the logistic regression models. Furthermore, a higher proportion of patients in the after group than in the before group received sedatives.

The most likely explanation for the lack of effect is that the scales complemented existing sedation and analgesia management in situations in which the duration of ventilation is already low compared with that of other ICUs. For example, median duration of mechanical ventilation in a study14 of 128 patients in the United States was 7.3 days in the control group. In a recent Australian study,30 duration of mechanical ventilation increased after introduction of a sedation algorithm, from 4.8 days to 5.6 days, supporting the view that ventilatory management in the closed ICU environment in Australia did not benefit from the addition of a universally applied objective assessment and protocol.


A higher proportion of patients in the after group than in the before group received sedatives.

 

Protocol-directed sedation reduces the duration of mechanical ventilation, ICU and hospital lengths of stay, and the need for tracheostomy among critically ill patients with acute respiratory failure,28 although these findings are not universal.31 Only a single report21 on the effect of introducing a sedation scale has been published. Although Chanques et al21 reported a reduction in the duration of mechanical ventilation in their study, similar to our study, they reported no difference in ICU length of stay. End points were different between the studies, and Chanques et al21 made no adjustment for possible confounding factors. Differences in case mix and severity of illness may explain the different outcomes.21 Although such differences are a limitation of before-and-after designs, this limitation may be partially overcome by multivariate analysis. After adjustment for age, sex, severity of illness, comorbid diseases, diagnosis, and before or after group, only the APACHE II score and diagnostic group were important determinants of mechanical ventilation of 96 hours or more.

Sedation and analgesia algorithms provide objective methods for managing sedation and pain levels in patients receiving mechanical ventilation.2 Use of sedation and weaning protocols that provide guidelines for the management of sedation probably influence outcomes rather than the specific choice of sedation or analgesia scale. However, in order to evaluate the benefit of these protocols, the contribution of introducing a sedation measurement tool should be understood. Changes to practice, such as daily wake-ups, can then be attributed to the practice change rather than to the scale used. In our study, the introduction of sedation and analgesia assessment scales did not confer any benefit in duration of mechanical ventilation and length of stay.

The study has several limitations. It was done at a single center, and therefore the results may not be generalizable to other units. However, the ICU is the largest in the state; it admits patients with a wide range of diseases and severity of illness and is similar to many ICUs of comparable size in Australia. The large sample size was achieved by collecting data for a 12-month period, thus providing sufficient power to account for exclusions (eg, patients receiving <6 hours of mechanical ventilation). The level of sedation may have been influenced by confounding factors such as interaction between sedation and analgesia, the patient’s condition, activity, extraneous noise, and circadian rhythms.32 However, assessments were done when no care activity had occurred for the previous 10 minutes and were done every 6 hours, day and night, minimizing the bias from these effects.

Selection bias may limit the validity of data on medication usage. Patients who had missing data on the use of sedatives were younger, sicker, had a longer length of stay in the ICU, and had longer duration of mechanical ventilation, but these differences were not significant. For patients who did have these data available, patients received sedatives for a longer period in the after group than in the before group, although length of stay in the ICU was similar between the 2 groups. This finding may indicate that patients in the before group did not receive adequate sedation and that the scales were useful in improving sedation /analgesia without an increase in the duration of mechanical ventilation. The greater use of sedatives also may be a consequence of inappropriate use of these scales to manage patients’ sedation.

Despite staff education before the introduction of the scales, staff members may have lacked skills in using these tools. However, in addition to staff education, senior nursing staff checked compliance with the tool daily, and interrater reliability was high ({kappa}= 0.98). Trained assessor and bedside nurses’ assessments were similar ({kappa}=0.96), so the tools most likely were used appropriately. Alternatively, the sedation and pain scales may have been inappropriate for this cohort. However, despite differences in case mix and severity of illness between ICUs, no reason suggests that results of previous studies cannot be applied to this critically ill cohort.


   Conclusion
Top
 Abstract
 Methods
 Definitions
 Statistical Analysis
 Results
 Discussion
 Conclusion
References
 
Using a sedation scale and pain scale to assist in the management of patients receiving mechanical ventilation did not decrease the duration of mechanical ventilation. This finding does not exclude a role for the scales in weaning patients from mechanical ventilation and in extubation protocols.

FINANCIAL DISCLOSURES
This study was supported in part by a research grant from the Western Australian Nurses Memorial Charitable Trust.

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SEE ALSO
To learn more about mechanical ventilation in critically ill patients, visit http://ccn.aacnjournals.org and read the article by Suzanne Burns, "Mechanical Ventilation of Patients With Acute Respiratory Distress Syndrome and Patients Requiring Weaning: The Evidence Guiding Practice" (Critical Care Nurse, August 2005).

To purchase electronic or print reprints, contact The InnoVision Group, 101 Columbia, Aliso Viejo, CA 92656. Phone, (800) 809-2273 or (949) 362-2050 (ext 532); fax, (949) 362-2049; e-mail, reprints{at}aacn.org.


   REFERENCES
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 Statistical Analysis
 Results
 Discussion
 Conclusion
 References
 

  1. Jacobi J, Fraser GL, Coursin DB, et al. Clinical practice guidelines for the sustained use of sedatives and analgesics in the critically ill adult [published correction appears in Crit Care Med. 2002;30(3):7260]. Crit Care Med. 2002;30(1):119–141.[Medline]
  2. Devlin JW, Boleski G, Mlynarek M, et al. Motor Activity Assessment Scale: a valid and reliable sedation scale for use with mechanically ventilated patients in an adult surgical intensive care unit. Crit Care Med. 1999;27(7):1271–1275.[Medline]
  3. Woods JC, Mion LC, Connor JT, et al. Severe agitation among ventilated medical intensive care unit patients: frequency, characteristics and outcomes. Intensive Care Med. 2004;30(6):1066–1072.[Medline]
  4. Arroliga A, Frutos-Vivar F, Hall J, et al. Use of sedatives and neuromuscular blockers in a cohort of patients receiving mechanical ventilation. Chest. 2005;128(2):496–506.[Medline]
  5. Shelly M. Sedation, where are we now [editorial]? Intensive Care Med. 1999;25(2):137–139.[Medline]
  6. Magarey JM. Sedation of adult critically ill ventilated patients in intensive care units: a national survey. Aust Crit Care. 1997;10(3):90–93.[Medline]
  7. Bair N, Bobek MB, Hoffman-Hogg L, Mion LC, Slomka J, Arroliga AC. Introduction of sedative, analgesic, and neuro-muscular blocking agent guidelines in a medical intensive care unit: physician and nurse adherence. Crit Care Med. 2000;28(3):707–713.[Medline]
  8. Slomka J, Hoffman-Hogg L, Mion LC, Bair N, Bobek MB, Arroliga AC. Influence of clinicians’ values and perceptions on use of clinical practice guidelines for sedation and neuromuscular blockade in patients receiving mechanical ventilation. Am J Crit Care. 2000;9(6):412–418.[Abstract]
  9. Mascia MF, Koch M, Medicis JJ. Pharmacoeconomic impact of rational use guidelines on the provision of analgesia, sedation, and neuromuscular blockade in critical care. Crit Care Med. 2000;28(7):2300–2306.[Medline]
  10. Ely EW, Truman B, Shintani A, et al. Monitoring sedation status over time in ICU patients: reliability and validity of the Richmond Agitation-Sedation Scale (RASS). JAMA. 2003;289(22):2983–2991.[Abstract/Free Full Text]
  11. Park G, Coursin D, Ely EW, et al. Balancing sedation and analgesia in the critically ill [commentary]. Crit Care Clin. 2001;17(4):1015–1027.[Medline]
  12. Kollef MH, Levy NT, Ahrens TS, Schaiff R, Prentice D, Sherman G. The use of continuous iv sedation is associated with prolongation of mechanical ventilation. Chest. 1998;114(2):541–548.[Medline]
  13. Wheeler AP. Sedation, analgesia, and paralysis in the intensive care unit. Chest. 1993;104(2):566–577.[Medline]
  14. Kress JP, Pohlman AS, O’Connor MF, Hall JB. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med. 2000;342(20):1471–1477.[Abstract/Free Full Text]
  15. Ostermann ME, Keenan SP, Seiferling RA, Sibbald WJ. Sedation in the intensive care unit: a systematic review. JAMA. 2000;283(11):1451–1459.[Abstract/Free Full Text]
  16. Shapiro BA, Warren J, Egol AB, et al. Practice parameters for intravenous analgesia and sedation for adult patients in the intensive care unit: an executive summary. Crit Care Med. 1995;23(9):1596–1600.[Medline]
  17. Young C, Knudsen N, Hilton A, Reves JG. Sedation in the intensive care unit. Crit Care Med. 2000;28(3):854–866.[Medline]
  18. Australian Council on Healthcare Standards. Guidelines for Intensive Care Units. Sydney, Australia: Australian Council on Healthcare Standards; 1997.
  19. Sessler CN, Gosnell MS, Grap MJ, et al. The Richmond Agitation-Sedation Scale: validity and reliability in adult intensive care unit patients. Am J Respir Crit Care Med. 2002;166(10):1338–1344.[Abstract/Free Full Text]
  20. Payen JF, Bru O, Bosson JL, et al. Assessing pain in critically ill sedated patients by using a behavioral pain scale. Crit Care Med. 2001;29(12):2258–2263.[Medline]
  21. Chanques G, Jaber S, Barbotte E, et al. Impact of systematic evaluation of pain and agitation in an intensive care unit. Crit Care Med. 2006;34(6):1691–1699.[Medline]
  22. Young J, Siffleet J, Nikoletti S, Shaw T. Use of a Behavioural Pain Scale to assess pain in ventilated, unconscious and/or sedated patients. Intensive Crit Care Nurs. 2006;22(1):32–39.[Medline]
  23. Rothman K, Greenland S. Modern Epidemiology. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.
  24. Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE II: a severity of disease classification system. Crit Care Med. 1985;13(10):818–829.[Medline]
  25. Douglas SL, Daly BJ, Gordon N, Brennan PF. Survival and quality of life: short-term versus long-term ventilator patients. Crit Care Med. 2002;30(12):2655–2662.[Medline]
  26. World Health Organization. International Classification of Impairments, Disabilities, and Handicaps: A Manual of Classification Relating to the Consequences of Disease. Geneva, Switzerland: World Health Organization; 1980.
  27. Hosmer DJ, Lemeshow S. Applied Survival Analysis: Regression Modeling of Time to Event Data. NewYork, NY: John Wiley & Sons Inc; 1999.
  28. Brook AD, Ahrens TS, Schaiff R, et al. Effect of a nursing-implemented sedation protocol on the duration of mechanical ventilation. Crit Care Med. 1999;27(12):2609–2615.[Medline]
  29. US National Center for Health Statistics. The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Annotated ed. Ann Arbor, MI: Commission on Professional and Hospital Activities; 1988.
  30. Elliott R, McKinley S, Aitken LM, Hendrikz J. The effect of an algorithm-based sedation guideline on the duration of mechanical ventilation in an Australian intensive care unit. Intensive Care Med. 2006;32(10):1506–1514.[Medline]
  31. Blackwood B, Wilson-Barnett J, Patterson CC, Trinder TJ, Lavery GG. An evaluation of protocolised weaning on the duration of mechanical ventilation. Anaesthesia. 2006;61(11): 1079–1086.[Medline]
  32. Freedman NS, Gazendam J, Levan L, Pack AI, Schwab RJ. Abnormal sleep/wake cycles and the effect of environmental noise on sleep disruption in the intensive care unit. Am J Respir Crit Care Med. 2001;163(2):451–457.[Abstract/Free Full Text]

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