AHRQ Safety Program for Mechanically Ventilated Patients
Summary
The elevation of the head of bed [HOB] to a semirecumbent position [at least 30 degrees] is associated with a decreased incidence of aspiration and ventilator-associated pneumonia [VAP]. The intervention is supported unanimously by all four leading guidelines, and newer publications in the field accept HOB elevation as an effective, low-cost, and low-risk intervention.
Society for Healthcare Epidemiology of America
2008—Society for Healthcare Epidemiology of America Guidelines: Strategies to prevent VAP in acute care hospitals: 2014 update1
- Recommends elevating the HOB [30-45 degrees] as a strategy to prevent aspiration.
ZAP the VAP: Ventilator-Associated Pneumonia
2008—Canadian VAP Prevention Guidelines: Evidence-based, clinical practice guidelines for the prevention of VAP2
- Recommends elevating the HOB to 45 degrees or, when not possible, to the highest degree of elevation circumstances permit.
American Thoracic Society
2004—Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia3
- Recommends the semirecumbent position [30-45 degrees] to reduce aspiration and VAP.
Centers for Disease Control and Prevention [CDC]
2003—CDC Guidelines for preventing Health-Care-Associated Pneumonia; evidence-based, clinical practice guidelines for the prevention of healthcare-associated pneumonia, including VAP4
- Recommends semirecumbent position [30–45 degrees] for prevention of aspiration.
| Observational Trial [Rose, 2010]5 | CON: Study focused on adult patients requiring mechanical ventilation in Australia and New Zealand intensive care units. Findings showed that actual backrest elevation was less than recommended and predominantly influenced by clinical and patient condition, where more acute patients had a lower head of bed [HOB]. Authors felt that more study is warranted to determine if the perceived difference in ventilator-associated pneumonia [VAP] rates is due to this phenomenon. |
| Randomized Controlled Trial [RCT] [van Nieuwenhoven, 2006]6 | CON: Randomized controlled trial [RCT] to assess the feasibility of the semirecumbent position for adult mechanically ventilated patients in the intensive care unit [ICU]. Patients must have required mechanical ventilation for more than 48 hours. The target for HOB elevation was 45 degrees. Unfortunately, the study failed to meet the target elevation of 45 degrees, and investigators compared 10-degree elevation versus 28-degree elevation. Comparison failed to show VAP reduction. |
| Quasi-experimental Study [Resar, 2005]7 | PRO: Quasi-experimental study. This study implemented the use of the Institute for Healthcare Improvement ventilator bundle. Findings showed that adherence to the bundle led to a significant reduction of VAP. One of the four interventions included in the bundle was HOB elevation to 30-45 degrees. |
| RCT [Drakulovic, 1999]8 | PRO: RCT. 86 patients were randomly assigned to semirecumbent or supine position. Study focused on medical and respiratory patients who required mechanical ventilation in the intensive care unit. Findings showed the semirecumbent body position reduces frequency and risk of nosocomial pneumonia, especially in patients who receive enteral nutrition. Study was stopped early after planned interim analysis found significant differences between the two arms. |
| Observational Study [Orozco-Levi, 1995]9 | PRO: Observational study focused on adult, critically ill patients requiring mechanical ventilation and nasogastric intubation. Study findings showed that irrespective of body position [supine or semirecumbent], patients with gastroesophageal reflex [GER] are at risk for gastric content aspiration. Additionally, the study concludes that while the semirecumbent position doesn’t completely protect from GER, it does protect against pulmonary aspiration of gastric contents. |
| Cohort Study [Kollef 1993]10 | PRO: Cohort study focused on medical, surgical, and cardiothoracic patients that required mechanical ventilation for longer than 24 hours. Study findings showed four factors to be independently associated with VAP: an organ system failure index ≥3, patient age ≥60 years, prior antibiotic treatment, and supine head positioning. |
| Crossover Trial [Torres, 1992]11 | PRO: Crossover trial focused on patients requiring mechanical ventilation and intubation. Study findings conclude that the supine position and length of time the patient is kept in this position are potential risk factors for aspiration of gastric contents. |
| Literature Review [Li Bassi, 2011]12 | Literature review: Reviewed nine RCTs and two animal studies to evaluate the role of body positioning on VAP. Findings showed a decrease in VAP due to semirecumbent position and reduction in gastric aspiration. |
| Clinical Review [Grap, 2010]13 | Clinical review: This review summarizes the epidemiology, pathophysiology, and risk factors associated with VAP and provides evidence-based recommendations for preventions. Review recommends the use of continuous backrest elevation of 30–45 degrees as an early prevention measure for VAP in the emergency department. |
| Systematic Review and Meta-analysis [Alexiou, 2009]14 | Systematic review and meta-analysis: Study analyzed seven RCTs to evaluate the effect of body position of patients requiring mechanical ventilation. Study findings showed that patients in the semirecumbent position have a significantly lower rate of clinical diagnoses of VAP than patients positioned supinely. |
| Clinical Review [Kollef, 2004]15 | Clinical review focused on clinical methods used for prevention of hospital-acquired pneumonia/VAP. With regard to HOB, the review recommends the implementation and use of semi-erect HOB positioning based on the findings of four randomized controlled trials. |
| Systematic Review [Collard, 2003]16 | Systematic review focused on all interventions that are beneficial to the prevention of VAP. Regarding HOB elevation, review recommends the use of semirecumbent position based on findings of three RCTs. |
Annotated Bibliography
Klompas M, Branson R, Eichenwald EC, et al. Strategies to prevent ventilator-associated pneumonia in acute care hospitals: 2014 update. Infect Control Hosp Epidemiol 2014 Aug;35[8]:915-36. PMID: 25026607.
- Muscedere J, Dodek P, Keenan S, et al. Comprehensive evidence-based clinical practice guidelines for ventilator-associated pneumonia: Prevention. J Crit Care 2008 Mar;23[1]:126-37. PMID: 18359430.
American Thoracic Society, Infectious Diseases Society of America. Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. Am J Respir Crit Care Med 2005 Feb;171[4]:388-416. PMID: 21481251.
- Tablan OC, Anderson LJ, Besser R, et al. Guidelines for preventing healthcare-associated pneumonia, 2003: Recommendations of CDC and the healthcare infection control practices advisory committee. MMWR Recomm Rep 2004 Mar;53:1-36. PMID: 15048056.
- Rose L, Baldwin I, Crawford T, et al. Semirecumbent positioning in ventilator-dependent patients: A multicenter, observational study. Am J Crit Care 2010 Nov;19[6]:100-8. PMID: 21041187.
CON: Observational trial—Study focused on the angle of the head of bed in adult patients requiring mechanical ventilation in Australia and New Zealand intensive care units [ICUs]. Findings showed that actual backrest elevation was less than recommended and was predominantly influenced by clinical and patient condition, where more acute patients had a lower head of bed [HOB]. Authors felt that more study is warranted to determine if the perceived difference in ventilator-associated pneumonia rates is due to this phenomena.
- van Nieuwenhoven CA, Vandenbroucke-Grauls C, van Tiel FH, et al. Feasibility and effects of the semirecumbent position to prevent ventilator-associated pneumonia: A randomized study. Crit Care Med 2006 Feb;34[2]:396-402. PMID: 16424720.
CON: Head of bed [HOB] at 45 degrees or supine – Assessment of the feasibility of the semirecumbent position for intensive care units. Study focused on 255 patients intubated within 24 hours of intensive care unit admission and required mechanical ventilation for more than 48 hours. 109 patients were assigned to the supine group and 112 to the semirecumbent group. An average elevation was 9.8 degrees and 16.1 degrees at day 1 and day 7, respectively, for the supine group and 28.1 degrees and 22.6 degrees at day 1 and day 7, respectively, for the semirecumbent group [p