Preventing Injury from Mechanical Ventilation
Albert Fantasia, RRT-NPS
Critical Care Manager
Rhode Island Hospital
Hasbro Children's Hospital
Providence, Rhode Island, USA
Results from the National Institutes of Health’s (NIH) Acute Respiratory Distress Syndrome Network (ARDSNet) study are well known, as are the study’s international recommendations for managing patients with acute lung injury (ALI), which have been adopted widely. However, working to prevent injury from mechanical ventilation encompasses a much wider array of techniques and strategies than ARDSNet protocols alone.
Mechanical Function
Today’s generation of computer-driven mechanical ventilators is remarkably reliable, but it is important to remember that a ventilator system may fail at any time. Most modern ventilators complete a self-check when “booting-up,” and the clinician can perform a system safety check. In some models, the clinician has the ability to bypass this check, which often is done when the clinician is under pressure to place the patient on the ventilator. Testing before ventilator use relies on the clinician’s ability to verify the integrity of the equipment and to ensure that it will release volume in the setting of unsafe airway pressures. Ventilator systems should undergo preventive maintenance to ensure proper functioning.
Intensive care unit (ICU) design can have a profound effect on the ability to hear ventilator alarms. When acoustics or the ventilator’s distance from the nursing stations affects the staff ’s ability to hear alarms, alternative methods must be used to warn staff of malfunctions. Remote alarm systems and an interface of ventilator-to-nurse call lights often are used to provide adequate audio and visual notifications from a distance. Clinicians should avoid setting generic parameters for alarm settings; values should be relevant to the patient’s condition.
When ventilator dysfunction is suspected, the clinician should possess the knowledge to troubleshoot the cause. A test lung at the bedside can be used to determine if the issue is related to the patient or is a true ventilator malfunction. In either case, the physician is able to determine the cause quickly and replace the ventilator if necessary.
Communication
A report released in 2002 by The Joint Commission lists communication breakdown among staff members as a cause in 16 of 23 ventilator-related injuries or deaths.(1) A plan of care should be developed and understood by all members of the multiprofessional team, and this plan should be updated as the patient’s condition changes. Effective communication may be a simple concept, but it can be hard to achieve. Initiatives that stress improved communication, such as the Institute for Healthcare Improvement’s (IHI) 5 Million Lives Campaign,(2) have been implemented in many U.S. hospitals. One of goals of this program is to disseminate evidence-based knowledge and foster collaborative relationships with all members of the healthcare team.
Reporting Medical Errors
Historically, reporting medical errors has been associated with punitive action for the individuals involved, thereby discouraging its practice. Hospitals that take a non-punitive approach in such reporting improve their odds of capturing errors and avoid repeating them in the future. This includes ventilator problems caused by equipment malfunction or clinician error. The hospital should encourage the reporting of actual errors as well as near misses or close calls. This open reporting may help ensure operational defects are identified and corrected.
Evidence-Based Practice
Evidence-based medicine (EBM) is the utilization of the best evidence when making clinical decisions in the care of individual patients. Evidence-based medicine has gained popularity in recent years because many physicians do not practice according to the best available evidence. Today’s technology makes these data current and readily available. Evidence-based medicine includes results from clinical trials as well as outcomes from clinical practice. The IHI(3) and other groups have included evidence-based practice as one of their initiatives in improving ICU outcomes. These groups collect data from research and best clinical practice and make the information available to clinicians around the world.
ARDSNetwork Recommendations. The ARDSNet study was conducted from 1996 to 1999 and randomized more than 800 patients to receive either a low tidal volume or high tidal volume strategy. The results showed a 25% increase in survivability when low tidal volumes were used.(4) Evidence-based strategies for ARDS ventilator management today include:
• Low tidal volume ventilation (4-6 mL/kg of ideal body weight)
• Optimal recruitment pressures
• Plateau pressure (pPlat) < 30 cm H2O
Current data show a correlation between ventilator-induced lung injury and an increase in the release of proinflammatory mediators into the circulation. This physiology and its contribution to organ system failure is referred to as biotrauma.(5) The newest evidence supports the use of lung-protective strategies more than ever. Even though data suggest much better outcomes with these interventions, they still are not being applied uniformly or in a timely fashion.(6)
The Ventilator Bundle. Ventilator associated pneumonia (VAP), a pneumonia that develops more than 48 hours after the patient is intubated, is the leading cause of death among hospital-acquired infections, exceeding the rate of death due to central-line infections, severe sepsis, and respiratory tract infections in the non-intubated patient.(7) In addition to increased mortality, VAP prolongs ventilator days, increases length of stay in the ICU, and increases the cost of hospital care. The ventilator bundle includes four components of clinical practice that achieve significantly better outcomes when used together than when implemented separately.
• Elevation of the head of the bed
• Daily sedation vacations and assessments of readiness for extubation
• Peptic ulcer disease prophylaxis
• Deep venous thrombosis prophylaxis
Sedation Vacation. Sedation vacation is the daily interruption of sedation on a mechanically ventilated patient receiving a continuous infusion of sedation. Kress et al.(8) showed a marked reduction in time on ventilation when patients had a daily interruption in sedation versus interruption at the clinician’s discretion. Decreased ventilator days will not only decrease VAP rates, as previously mentioned, but also reduce the opportunity for further lung injury due to mechanical or clinician error.
Staffing
In 2002, The Joint Commission listed insufficient staffing as one of the causes of ventilator-induced injury.(1) Because of improvements in ventilator technology, the clinicians’ ability to manage patients and to receive timely alerts has improved dramatically. Historically, clinicians allocated their time to patients’ care based on department policy, i.e., every ventilator was assessed every 2 hours, a system that prevents the clinician from spending the most time with the sickest patients. Staffing based on acuity enables the clinician to deliver the appropriate care, treating patients according to need rather than volume (see Table 1). It promotes efficient use of resources and allows staff to manage ventilator patients safely during times of high volume and high acuity, situations where errors may be possible due to staff shortages.
Conclusion
Understanding the hazards that accompany mechanical ventilation and careful attention to details described in the aforementioned concepts can decrease the potential for injury from mechanical ventilation.
References
1. The Joint Commission. Sentinel Event Alert: Preventing ventilator-related deaths and injuries. Issue 25, February 26, 2005. Available at: http://www.jointcommission.org/SentinelEvents/ SentinelEventAlert. Accessed January 15, 2008.
2. Institute for Healthcare Improvement. Protecting 5 Million Lives from Harm. Available at: http://www.ihi.org/IHI/Programs/Campaign. Accessed January 15, 2008.
3. Institute for Healthcare improvement. Available at: http://www.ihi.org. Accessed January 15, 2008.
4. The Acute Respiratory Distress Syndrome Network. Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. New Eng J Med. 2000;342(18):1301-1308.
5. Slutsky AS, Dos Santos CC. The contribution of biophysical lung injury to the development of biotrauma. Annu Rev Physiol. 2006;68:585-618.
6. Institute for Healthcare Improvement. Sepsis: Case for Improvement. Available at: http://www.ihi.org/IHI/Topics/CriticalCare/Sepsis/SepsisCaseforImprovement.htm. Accessed January 15, 2008.
7. Ibrahim EH, Tracy L, Hill C, et al. The occurrence of ventilator-associated pneumonia in a community hospital: Risk factors and clinical outcomes. Chest. 2001;120(2):555-561.
8. Kress JP, Pohlman AS, O’Connor MF, Hall JB. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. New Eng J Med. 2000;342(20):1471-1477.
