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American Journal of Critical Care. 2005;14: 389-394
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Improving Oral Care in Patients Receiving Mechanical Ventilation

By Constance J. Cutler, RN, MS, CIC and Nancy Davis, MA. From Clinical Excellence Department, Advocate Health Care, Oak Brook, Ill (CJC), and Medical Education and Research, Advocate Health Care, Park Ridge, Ill (ND).


   Abstract
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 Abstract
Methods
 Data Analysis
 Results
 Discussion
 References
 
• Background Comprehensive oral care is an evidence-based prevention strategy to reduce the risk of ventilator-associated pneumonia in patients receiving mechanical ventilation. Until recently, no comprehensive guidelines or standards existed to define necessary tasks, methods, and frequency of oral care to provide patients with optimal results.

• Objectives To observe current practice of, define best practice for, and measure compliance with standardized comprehensive oral care.

• Methods This observational study was part of a larger research study performed at 5 acute care hospitals. Time blocks of 4 hours were randomized over 8 intensive care units and the 7 days of the week. Baseline data were collected before implementation of multifaceted education on an oral-cleansing protocol; interventional data were collected afterward.

• Results Oral care practices were observed for 253 patients. During the baseline period, oral cleansing was primarily via suction swabs. Toothbrushing and moisturizing of the oral tissues were not observed. Only 32% of the patients had suctioning to manage oral secretions. During the interventional period, 33% of patients had their teeth brushed, 65% had swab cleansing, and 63% had a moisturizer applied to the oral mucosal tissues. A total of 61% had management of oral secretions; 38% had oropharyngeal suctioning via a special catheter.

• Conclusions Implementation of an evidence-based oral cleansing protocol improved the care of patients receiving mechanical ventilation. Multifaceted education and implementation strategies motivated staff to increase oral care practices.

Oral comfort and hygiene measures have long been an important aspect of nursing care for patients receiving mechanical ventilation, but a gap exists between what oral care measures are indicated and the actual care patients receive. Before 2005, no comprehensive guidelines or standards existed that defined tasks, methods, and frequency of oral care interventions that will provide patients with optimal results.1 Therefore, great variability exists from nurse to nurse.


No comprehensive guidelines exist that define the method and frequency of oral care.

 

Different aspects of current oral care practice for critically ill patients were described in 2 recent reports.2,3 In a study2 of intensive care unit (ICU) nurses, a majority reported that they provided oral care 5 or more times daily for intubated patients, primarily with sponge swabs, but documentation on flow sheets revealed that oral care was performed only slightly more than 1 time per day. Sole et al3 found that less than half of the sites participating in the Survey of Suctioning Techniques and Airway Management Practices study had a written oral care policy for intubated patients, although current critical care nursing manuals advocate oral care ranging from every 2 hours to every shift (8–12 hours). Also, most nurses in the study stated that they performed mouth care every 4 hours with swabs, but in another investigation Sole et al4 found that 67% of patients had not had any oral care documented within the preceding 4 hours. Clearly, practices vary from site to site. The disparity between what nurses think they do and what is actually documented raises questions about the reliability of documentation and the consistency of practice.


For oral care of critically ill patients, what nurses think they do differs from what is actually documented.

 

Microbial colonization of the oropharynx and of dental plaque has been associated with systemic and respiratory diseases, most notably ventilator-associated pneumonia (VAP).2,5–13 VAP affects 8% to 28% of patients receiving mechanical ventilation, with mortality rates ranging from 24% to 50%. Mortality rates may be as high as 76% for infections caused by high-risk pathogens such as Pseudomonas or Acinetobacter.14 Prolonged ICU and hospital stays result in increased costs ranging from $30 000 to $40 000 per case.15,16

Unlike healthy adults, most hospitalized and institutionalized patients are colonized with potential respiratory pathogens.7,11,17–21 When a patient’s respiratory status deteriorates to the point that intubation is necessary, lifesaving efforts such as an artificial airway can place the patient at risk for direct introduction or microaspiration of pathogens into the lower part of the respiratory tract. Therefore, reducing a patient’s risk through oral care interventions has become critical in preventing adverse outcomes such as VAP.

In the Guidelines for Preventing Health-Care-Associated Pneumonia,22 the Centers for Disease Control and Prevention issued the following recommendation:

Develop and implement a comprehensive oral-hygiene program (that might include the use of an antiseptic agent) for patients in acute-care settings or residents in long-term care facilities who are at high risk of developing health-care-associated pneumonia.

Current literature22–38 supports the following components for comprehensive oral hygiene for patients receiving mechanical ventilation:

Studies39–41 indicate that multifaceted implementation strategies are more likely than single-faceted strategies to be effective at changing behavior and thus moving best practices into action. Outlining specific care protocols or procedures facilitates consistency and quality care through standardization.

The purpose of the study reported here was to observe current practice of oral care in patients receiving mechanical ventilation, define best practices, and measure compliance with an intervention of standardized oral care. An additional objective was to improve oral care tasks and frequency via an educational intervention, which included oral care kits.


   Methods
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 Abstract
 Methods
Data Analysis
 Results
 Discussion
 References
 
The study was approved by the appropriate institutional review board. Patients were observed at 5 Chicago area acute care hospitals: 2 community teaching hospitals and 3 community hospitals including 3 trauma centers. The mean census ranged from approximately 250 to 600 patients for the 2 teaching hospitals and from 150 to 225 patients for the 3 community hospitals. Observations were made in 8 ICUs; patients had medical, surgical, neurological, cardiac, and trauma diagnoses.

The study was part of a larger study on the impact of oral care on VAP. The larger study consisted of 3 phases: baseline, education, and intervention. During the baseline phase (December 2002 through March 2003), patients in each unit received the unit’s routine oral cleansing. None of the study sites had an oral cleansing protocol that defined frequency and tools for patients receiving mechanical ventilation. Nurses, respiratory therapists, and associated staff were educated and trained in April 2003 to follow a standardized comprehensive oral cleansing protocol (Table 1Go). As of May 1, 2003, trained personnel in each unit were instructed to follow the standardized comprehensive oral-cleansing protocol for all patients receiving mechanical ventilation in their unit. The intervention period was May through August 2003. During this period, specially designed 24-hour oral care kits were mounted on wall brackets near each patient’s bedside. The kit provided all the tools necessary to perform the oral care tasks as outlined in the protocol (Table 1Go) and were organized to facilitate ease of use and compliance with the protocol.


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  		Table 1 Oral cleansing protocol

 
Observation of oral care performed by nurses, respiratory therapists, and associated staff was nested into the baseline (February and March 2003) and intervention (July and August 2003) periods of the larger study described. To avoid performance bias due to the Hawthorne effect, the investigators purposely scheduled the observations during the last 2 months of the intervention phase of the larger study (Table 2Go). In each of the 2-month periods, observations were done during random blocks of 4 hours that included early morning through evening shifts. Randomization was established by using a computer program to select all ICU sites, day of the week, and time of the day (eg, early morning or afternoon) so that all sites, days, and times had equal chances of being selected for each draw.


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  		Table 2 Time line for the study

 
In order for the observers to have clearance into the ICUs, each ICU manager was informed as to when and why they would be present in the unit, but ICU staff were not informed as to when the observers would be present in the unit or why. During the baseline period, ICU staff were not informed of the upcoming change in protocol or intervention. If a staff member inquired, he or she was informed that the observer was researching care practice for patients receiving mechanical ventilation.

On the basis of the standardized comprehensive oral-cleansing protocol (Table 1Go), a specially designed data collection form was designed for use by the 6 trained observers. The observers noted frequency, tasks, and tools used for oral care during the randomized 4-hour time blocks by walking around the unit and watching nurses and respiratory care personnel who were performing tasks. In addition, when an observer heard the sounds of suctioning, he or she would note that. Observers also recorded the types of oral cleaning products that were located at the patients’ bedsides and in the unit.


   Data Analysis
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 Abstract
 Methods
 Data Analysis
Results
 Discussion
 References
 
Descriptive statistics, mean and SD for continuous data and numbers and percentages for categorical data, were calculated for all variables recorded. Observations recorded during the baseline phase were compared with those made during the intervention phase by using {chi}2 analysis or the Fisher exact test. Because the length of time patients were receiving mechanical ventilation was not normally distributed, a Mann-Whitney test was performed. A 2-tailed P level of .05 was considered significant in all analyses. Analyses were performed by using SPSS software (release 12.0, SPSS Inc, Chicago, Ill).


   Results
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 Abstract
 Methods
 Data Analysis
 Results
Discussion
 References
 
A total of 172 hours of observation were completed: 84 during the baseline phase and 88 during the intervention phase. Number of random blocks of time, ICU beds available, ICU patients, and patients receiving mechanical ventilation were similar during the 2 phases (Table 3Go). A total of 253 patients were observed: 139 (55%) during the baseline phase and 114 (45%) during the intervention phase. The length of time patients received mechanical ventilation differed significantly between the 2 phases; median lengths were 72 hours (3 days) for the baseline phase and 120 hours (5 days) hours for the intervention phase (P < .001 by Mann-Whitney test).


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  		Table 3 Results for the 5 sites

 
In general, during the baseline phase, the oral care observed was predominately cleansing with suction swabs impregnated with sodium bicarbonate and moistened with 1.5% hydrogen peroxide solution. In 2 ICUs, suction toothbrushes were available, but according to observations and product utilization data from materials management, these brushes were rarely used. At 1 of the 5 sites, a 2-handed technique was used to cleanse the oral cavity with a nonsuction swab, and then excess solution was removed by using a tonsil suction device.

Every aspect of oral care performance increased significantly after the educational intervention (Table 4Go). During the intervention phase of observation, all aspects of oral care were performed. During the baseline phase, not a single patient who was observed had the oral cavity assessed, teeth brushed, lips and mouth moisturized, oropharyngeal area suctioned, or suction tubing changed.


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  		Table 4 Oral care results

 

Before implementation of a standardized oral cleansing protocol, not 1 patient observed had the oral cavity assessed, teeth brushed, lips and mouth moistened, or suction tube changed; after implementation, every aspect of oral care increased significantly.

 

The 2 oral care tasks that were performed during the baseline phase were performed more frequently during the intervention phase. During the baseline phase, patients who received suction swabbing of the teeth and mouth and suctioning of the mouth and pharynx received the care every 4 hours. In contrast, during the intervention phase, 24% of patients had suction swabbing of the teeth and mouth and 36% received suctioning of the mouth and pharynx every 2 hours. Except for toothbrushing, the remaining oral care procedures performed during the intervention phase were typically completed every 2 to 4 hours.


   Discussion
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 Abstract
 Methods
 Data Analysis
 Results
 Discussion
References
 
The major limitation of this observational study was that the observations were made in blocks of 4 hours. The results may be biased because each block encompassed less than an entire day and so the true hourly frequency of oral care performed could not be determined. Of the 5 ICUs, 2 are large; for these 2 units, possibly some oral care performed was not observed because an observer could not be at both ends of the unit at the same time. None of the observations included the hours from 11 PM to 5 AM because an assumption was made, on the basis of nursing staff feedback, that a majority of ICU staff would not disturb a sleeping patient to provide oral care; therefore, a decision was made not to perform observations during that period. In addition, observations from 8 PM to 11 PM were also limited.

Interrater reliability was not established among the observers, but observers were trained to identify the types of oral care provided as part of the larger study. Although an attempt was made to minimize bias due to the Hawthorne effect by making observations during the second 2 months of the larger study, the bias still could have occurred because of the staff members’ heightened awareness of oral care practices. However, use of the specially designed 24-hour oral care kits did decrease during the last month of observation, indicating that the Hawthorne effect was not a considerable bias.

The number of oral care tasks observed and the frequency with which tasks were performed were greater during the interventional phase than during the baseline phase. This finding supports the result of other studies39–41 that multifaceted implementation strategies improve oral care performed by staff caring for patients receiving mechanical ventilation. Before our study, the available literature2,3 indicated a lack of definition and frequency of oral care protocols for critical care patients, including patients receiving mechanical ventilation. A review of dental and periodontal literature was necessary before we could develop a comprehensive definition of oral care hygiene.

The steps involved in developing a systemwide oral care protocol included forming a multidisciplinary study leadership team, reviewing supporting scientific literature and anecdotal experiences, observing the performance of oral care on the ICUs during the baseline phase, implementing intensive educational programs, and measuring the outcome during the intervention observation phase. Involving both nurses and respiratory therapists in the study broke down barriers that have traditionally fragmented tasks according to job discipline.

We think that oral care is an important component of a comprehensive program to prevent VAP. Although our protocol called for oral care every 2 hours, the observational results indicated that care was more often provided every 4 hours. Further research is needed to determine the ideal frequency of oral care and the relationship of frequency to preventing infection in patients receiving mechanical ventilation.

Previous research2,3 indicated that perceptions of oral care practices differed from the reported frequency of the practices in the medical record. Nurses were more likely to report that they provided adequate and frequent oral care than was shown in documentation. Our results indicate that without a standardized comprehensive protocol for oral care hygiene, oral care was performed infrequently and that important aspects of care were not performed. Despite the availability of oral care tools, the tools were not used. This finding confirms the results of previous investigations2,3 about the variance of oral care practices in the critical care environment. In our study, use of the protocol decreased the variability of oral care provided among and between nurses and respiratory therapists. Our results indicate that implementing a standardized oral care protocol and providing appropriate tools at the bedside will increase the frequency and comprehensiveness of oral care provided.


Although the protocol indicated that oral care should be provided every 2 hours, oral care was more often provided every 4 hours.

 


Use of an oral care protocol increased the number and frequency of oral care tasks performed.

 


   ACKNOWLEDGMENTS
 
This study was supported in part by a research grant from Sage Products, Inc, Cary, Ill. The research described was performed at 5 Advocate Health Care hospitals in Illinois: Advocate Christ Medical Center, Oak Lawn; Advocate Good Samaritan Hospital, Downers Grove; Advocate Illinois Masonic Medical Center, Chicago; Advocate South Suburban Hospital, Hazel Crest; and Advocate Trinity Hospital, Chicago.

To purchase 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.


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 Abstract
 Methods
 Data Analysis
 Results
 Discussion
 References
 

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