Critical Care Plus
High-Tech Beds: Better Outcomes or Needless Expense?
Much of the evidence is negative
Specialty beds marketed for ICU patients range from simple air-filled mattresses designed for use on ordinary hospital beds to high-tech, electronically controlled rotating or vibrating devices. Specialized beds can become a bone of contention between nurses, to whom bed companies direct their marketing efforts, and physicians, many of whom believe the lion’s share of benefits accrue to the manufacturer.
This appears to be especially true of the automated rotational beds that rent for $150-250/d. Though some ICU nurses are convinced that these beds improve outcomes, many physicians consider the evidence base that such beds improve outcomes to be shaky at best.
"My hospital spends an enormous amount of money renting these beds each year, and there are frequent disagreements at the bedside when nurses urge physicians to put their patients on them," says David J. Pierson, MD, professor of medicine at the University of Washington in Seattle. "There is substantial marketing literature but I am not impressed by it."
Study Finds No LRIS Difference
Investigators in a study designed to test the hypothesis that automated rotational therapy reduces the incidence of respiratory complications associated with mechanical ventilation found no significant difference in the incidence of lower respiratory tract inflammatory syndrome (LRIS) in the group using automated rotational beds (17% vs 26%; P = 0.15).
This was a prospective, randomized multicenter trial of intubated, mechanically ventilated patients free of respiratory infection. Study subjects used a standard intensive care unit bed or an automated rotational bed that could turn the patient as much as 32° from the horizontal at a rate of 8 times per hour.
Study investigators did find a significantly lower incidence of urinary tract infection (11% vs 27%; P < 0.05) in the patients treated with automated rotational beds in this study. But nurses involved in this study noted that eight of the patients using automatically rotated beds became anxious. No other significant differences in the development of other clinical events were observed.
Patients in this study were followed until successful extubation, death, or development of a LRIS. Other clinically important events (ie, cardiac, urinary, gastrointestinal, neuropsychiatric) were also recorded.1
Another study that evaluated the effect of continuous lateral rotational therapy on the development of ventilator-associated pneumonia in 37 patients requiring long-term mechanical ventilation found significantly lower prevalence of pneumonia (17.6%) as compared with control patients (50%; P < .05). Researchers also found that developing pneumonia after entering the study was also significantly delayed for those patients who experienced continuous lateral rotational therapy, 29 ± 8 days vs 12 ± 2 days in controls (P < .05). However, unit mortality, total ventilator days, and the number of successful ventilator weanings did not differ significantly between groups.2
In other words, in patients requiring long-term ventilator care, continuous lateral rotational therapy reduced the prevalence of pneumonia but did not seem to affect mortality or the period of mechanical ventilation.
Mark Astiz, MD, of the Department of Medicine at New York Medical College, was one of the researchers in this study. Astiz observes that he and fellow researchers elected to do the study because data in other groups of patients indicated that using rotational beds could be associated with reduction in pneumonias.
Patients often develop nonfatal pneumonias that increase both the lengths of hospital stay and time on a ventilator, Astiz notes, adding that his team didn’t perceive any difference in outcomes. "Significant reduction in pneumonia didn’t really improve overall survival," Astiz says.
Joyce Weisshaar, PNP at Children’s Memorial Hospital in Chicago, says her facility elected not to go with automatic rotational therapy because hospital had experienced better success by keeping patients prone. When rotational therapy first came out several years ago a representative of a bed company demonstrated the bed. "Our physicians attended a presentation by a bed company representative but when they looked at the numbers, they found we were having more success proning patients than bed research indicated we could expect," Weisshaar says.
Proning, or positioning patients on their stomachs, increases oxygenation by allowing more space for lungs to expand Weisshaar explains. "We used the rotational bed one time but the patient was too unstable." Weisshaar says the current practice in her hospital is turning patients on to their stomachs once a day for 20 hours.
Weisshaar adds that a current nursing study originating at Boston Children’s Hospital is investigating whether proning decreases hospital length of stay and days on a ventilator. Perhaps when that study is completed proning will be the position of choice.
For more information contact David Pierson, MD, at (206) 731-2148; Mark Astiz, MD, at (212) 604-2004; Joyce Weisshaar, PNP, at (773) 880-6930.
1 MacIntyre N, et al. Automated rotational therapy for the prevention of respiratory complications during mechanical ventilation. Respir Care. 1999;44: 1447-1451.
2 Kirschenbaum L, et al. Effect of continuous lateral rotational therapy on the prevalence of ventilator-associated pneumonia in patients requiring long-term ventilatory care. Crit Care Med. 2002;30(9):1983-1986.