BBI Contributing Editor

NEW ORLEANS The American Association of Critical Care Nurses' (AACN; Aliso Viejo, California) National Teaching Institute (NTI) always is an interesting experience. Over the past few years there has been a subtle shift among critical care nurses. The dominant themes at the conference used to be centered on lamenting the fact that nurses didn't receive the respect they deserved. While that theme is still in evidence, the difference is that the AACN is actively promoting and empowering change. Perhaps this is due to the continuing nursing shortage and the resultant increased need on the part of hospitals to make sure that their nurses are listened to and cared for lest they leave. This year, the AACN is advancing its six essential standards for establishing and sustaining healthy work environments, which include: skilled communication, true collaboration, effective decision-making, appropriate staffing, meaningful recognition and authentic leadership.

One example of how these standards relate to staff nurses is the AACN's active encouragement of nurses to become part of any hospital committee looking to purchase technology or other products used daily by nursing. The AACN cited the following excerpt from a nurse who was asked to be the representative on her hospital's product committee: "They (the rest of the committee) listen to me when I talk about which products work for patients and which ones don't. The chairperson told me most of the committee members would never know a bedside nurse's perspective."

While most of the conferences that The BBI Newsletter covers are highlighted by breaking results from medical research, the NTI presentations feature technology that has been (at least initially) studied and already is being used in many critical-care units around the country. The emphasis at the NTI is on enabling clinicians to better use these technologies to enhance patient care.

To that end, the NTI has become a mixture of education and salesmanship, with nurse clinicians offering presentations for continuing education credit throughout the entire vendor exhibit time directly in the vendors' booths. The vendors love this approach because nurse colleagues are telling their peers of the virtues of their products, bypassing the salesman until the benefits of the product have been explained. Is it education or is it a way to sell technology using "expert" testimony? It truly is a little of both and at this year's May meeting at the Ernest N. Morial Convention Center, the AACN required each clinician presenting a formal lecture (located in a classroom and not in a vendor booth) to disclose any association the speaker had with any technology company.

Hypothermia's use in neurologic outcomes

One of the recent trends discussed in both formal lectures and within vendor booths was the use of mild therapeutic hypothermia (lowering of the patient's core body temperature) to improve neurologic outcome following cardiac arrest. The goal of this technology is the improvement of the survival rates and the quality of life for out-of-hospital cardiac arrest patients. Currently, three out of four cardiac arrests occur outside of the hospital, with the person having a 1% to 5% chance of surviving to hospital discharge; and of these few who do survive to discharge only 2% have a good neurologic outcome. Cardiac arrest victims have eight to 10 minutes before neurologic changes begin to occur and it has been thought that the longer time to resuscitation, the poorer the outcome.

Hypothermia has been used successfully for years during cardiac surgery involving cardiopulmonary bypass as a means of protecting the brain from injury. Now studies are showing benefit to those who suffer sudden cardiac arrest as well in the studies cited at the NTI, about 40% to 50% of patients with cardiac arrest longer than eight to 10 minutes who were treated with lowering of their body temperature returned to a normal neurological state. At vendor booths and in formal presentations, nurses had interesting anecdotal stories of patients whom they assessed as being beyond the ability to return to "normal" but who recovered well. Because the process of employing hypothermia has not been adequately studied as of yet, protocols are evolving; but an advisory statement was published by the Advanced Life Support Task Force of the International Liaison Committee on Resuscitation (ILCOR) recommending that out-of-hospital cardiac arrest patients be cooled to between 32 degrees and 34 degrees Celsius (around 91 degrees Fahrenheit) for 12 to 24 hours when the initial rhythm found in the cardiac arrest victim was ventricular fibrillation. The ILCOR statement also acknowledged that cooling may be beneficial for other heart rhythms and for use on cardiac arrest victims from within the hospital. ILCOR includes the American Heart Association (Dallas).

Cooling of cardiac arrest patients is a standard protocol at Harborview Medical Center, one of the hospitals participating in the most recent research. Cooling of patients has historically been achieved by nurses placing ice bags at a patient's axilla and groin and covering the patient with a cooling blanket not a very scientific method and one that makes maintaining a patient's temperature between 32 and 34 degrees Celsius almost impossible. Using this antiquated method, nurses have to monitor the patient closely to prevent shivering (which is a reflex reaction that quickly elevates body temperature), and they often have to remove the ice and to place warm blankets on the patient to prevent over-cooling. This approach is extremely nursing-intensive and often requires two nurses to care for one patient. Harborview Medical Center now uses the Arctic Sun cooling device from Medivance (Louisville, Colorado), and any hospital that is serious about instituting a cooling protocol for post-cardiac arrest patients will need to purchase some company's cooling product.

At this year's NTI, there were a number of companies offering cooling devices that not only reduce the number of nurses required to care for these patients but control the patient's core temperature much more precisely (see Table 4).

Medivance showed the non-invasive Arctic Sun system, which consists of pads wrapped around a patient that allows temperature-controlled water to flow in response to feedback from a patient temperature probe. The pads are made of a biocompatible hydrogel layer (the same material that some wound healing manufactures use in their products) and are radiolucent so that X-rays can be obtained without the removal of the pads. In addition, the pads contain no latex so that they do not interfere with magnetic resonance imaging. The pads cover 40% of a patient's body surface over the abdomen, back and thighs and are fashioned so that central intravenous lines are not covered. The pads are easily peeled back so that clinicians can listen to heart sounds and assess a patient's abdomen. One set of pads can be used up to 72 hours on one patient; the pads are single-use only and the company lists them for around $1,000. The Arctic Sun cooling device itself lists for around $30,000.

Alsius (Irvine, California) offered a different approach to patient cooling with its Coolgard 3000 system. The company also uses patient temperature as the feedback to temperature control but instead of a non-invasive approach, it employs either a central venous or femoral vein catheter for cooling; there are other lumens on these catheters that allow infusion of fluids. The company's belief is that most people who suffer a cardiac arrest have central lines put in for monitoring purposes so why not one for more controlled cooling? The Coolgard cooling system costs around $27,000, but the company indicated that it was willing to negotiate if a hospital purchased a set number of catheters.

Far and away the most cost-effective cooling solution shown at NTI was that offered by Cincinnati Sub Zero (Cincinnati). This company has been in business for 40 years and apparently has sold enough hypothermia units that it can offer them for around $5,000, with the pads that cover the patient selling for $100. This company is the only one to offer a head wrap cooling unit, which cools the blood flow to a patient's brain. The representatives in the Cincinnati Sub Zero booth pointed out that many hospitals already have its Blanketrol II base cooling unit in use, so hospitals would simply need to purchase more of the single-use patient cooling/warming covers in order to institute the cooling of post-cardiac arrest patients.

Cooling of patients also is being investigated for the treatment of stroke and other neurological patient conditions. Fever is common in patients with acute neurologic conditions and independently predicts poor outcome. Researchers are not certain why elevated temperatures are so dangerous or why cooling post cardiac arrest patients helps them to recover, but the thought is that lower temperatures reduce the body's demand for oxygen and glucose and preserve ischemic tissue.

Reducing sepsis is another current topic of research among critical-care investigators and offers another use for patient cooling systems. GMP Wireless (Fort Lauderdale, Florida) showed its solution for reducing sepsis through use of the LifeSync Wireless system, a single-use disposable cable system that remains on a patient throughout his or her hospital stay. The system sends the patient's ECG signal using Bluetooth wireless technology to display on any patient monitor. LifeSync offers 3-, 5- and 12-lead continuous monitoring as well as diagnostic 12-lead disposable status. The company cites a statistic of 77% chance of some antibiotic resistant pathogen being present on non-disposable ECG wires, which the LifeSync monitoring lead system circumvents.

New monitoring applications

Wolfe Tory Medical (Salt Lake City) was showing a unique device called the AbViser for monitoring increased pressure in the intra-abdominal area. A number of studies concerning increased intra-abdominal pressure have been done to confirm the association between this and organ function. This research is still in the basic stages (common definitions and measurement methods are still being worked out) but there is growing evidence regarding the interaction between the abdominal and thoracic areas especially for patients with too much fluid in their circulation.

The AbViser integrates directly with a patient's Foley catheter (urine drainage system) in a closed system mode. The AbViser is connected to a transducer and monitor via a valve that allows sterile saline to be infused into the patient's bladder. After infusion, a measurement of the patient's intra-abdominal pressure is taken. Recent studies (Malbrain et al., Critical Care Medicine, February 2005) have shown that increased intra-abdominal pressure should be considered as an "organ dysfunction" for which specific diagnostic and therapeutic interventions are needed. The authors stated that they believe that every patient in a critical care area should have their intra-abdominal pressure measured within the first days on a unit because they saw increased intra-abdominal pressure as a precursor to organ damage.

The measuring of intra-abdominal pressure is new enough that a predictive number of patients who might benefit from this technology would be premature; however, some of the conditions that especially warrant intra-abdominal pressure monitoring include: sepsis, pancreatitis, peritonitis, bowel obstruction, abdominal tumors, abdominal aortic aneurysms and trauma. This system is in use at the University of Utah Hospital (Salt Lake City) and other, mainly larger, hospitals.

Medwave (Danvers, Massachusetts) used the NTI to introduce its new non-invasive intermittent blood pressure device, a small device that fits comfortably over a patient's wrist. Medwave's technology is designed to be used with an artery and bone together; therefore the radial artery (wrist) is ideal. The Primo device automatically (minimally) compresses over a patient's radial artery. During the compression, it is looking for the point of maximum energy transfer by measuring 250 data points and then applying this data to an algorithm to determine the patient's systolic, diastolic and mean blood pressure as well as heart rate. Complete occlusion of the radial artery never occurs, and the process is very comfortable for patients.

The non-continuous Primo device weighs less than five pounds. Readings have been shown to correlate well to arterial catheter readings. Medwave also offers the Vasotrac APM205A for continuous non-invasive blood pressure monitoring. Vasotrac APM205A uses the same technology as Primo but is hardwired from a wristpiece to a monitor that displays the blood pressure numbers as well as a pressure waveform. The readings are automatically taken every 15 heartbeats. Both devices have a mode intended to filter out movement, but neither appeared to do a particularly good job of that when demonstrated in the company's booth. Patients will definitely need to remain still and have the device in a stable position in order to assure accurate readings. The operating room and comatose patients would be excellent candidates for this new unit; others will need to cease any activity every 15 heartbeats in order to assure comparable readings.

Welch Allyn (Beaverton, Oregon) introduced its newest Propaq LT continuous monitor for ambulatory, bedside and transport applications. It is the Welch Allyn monitoring business's most rugged and versatile monitor to date. The unit weighs less than two pounds without the optional transport holster and is about the size of a paperback book, but can withstand the shock of being dropped from six feet. Propaq LT offers 3- or 5-lead ECG, SpO₂, NIBP and respiration and can be used for neonatal, pediatric or adult patients. There also is optional wireless connectivity to Welch Allyn's Acuity Central Stations via FlexNet. At around $5,000, this unit is intended to be used everywhere throughout a hospital but the ICU and even beyond hospital walls.

Draeger Medical (Telford, Pennsylvania) officially announced its Infinity OneNet as part of Draeger's Infinity enterprise solution. OneNet allows hospitals to run wired and wireless patient monitoring systems on the hospital's existing network infrastructure rather then requiring its own separate dedicated network. OneNet allows a hospital's existing enterprise network to provide patient monitoring in parallel with its commercial and administrative applications. And it lets hospitals merge their ISM-band, 802.11b wireless network traffic with the 802.3 wired network traffic from their conventional patient monitors.

Draeger also reported the release of its Apollo platform anesthesia work station, as a workflow solution that not only provides assistance through therapy but also has an open-platform architecture that enables it to be integrated into a hospital's existing workflow. Apollo was designed to offer all-around performance and to serve as a personal anesthesia assistant as well.

Spacelabs Medical (Issaquah, Washington) showed the first integrated USB bedside bar code scanner enabling rapid patient admissions via the use of the bar code on the admitting patient's hospital ID bracelet and the scanner, which is connected through a USB port on Spacelabs' SL 2400 monitor. With the scan of the patient bracelet, the monitor is populated with patient data, all at the point of care, offering Spacelabs' customers a new level of connectivity and clinical data integration.

Nihon Kohden (Foothill Ranch, California) reported receiving FDA clearance for its NTX non-invasive telemetry transmitter that monitors ECG, Sp0₂, respiration and non-invasive blood pressure essentially the same parameters offered by Welch Allyn's new Propaq LT. The transmitter operates in the WMTS frequency band and uses three alkaline AA batteries. NTX is designed to offer more flexible monitoring on higher acuity patients. Nihon Kohden also showed its new Mainstream CO₂ Cap-One sensor which provides accurate CO₂ monitoring for non-intubated patients using a substantially reduced mainstream sensor. The sensor is attached to a disposable oral and nasal adaptor and placed directly at the point of expiration, which allows non-intubated patients to be monitored.

Aside from monitoring products, an interesting patient comfort device called the LidoSite Topical System was shown by B. Braun (Bethlehem, Pennsylvania). It is is a topical anesthetic system used to reduce the pain of venipuncture. The system consists of a single-use, prefilled (with Lidocaine and Epinephrine) patch placed over the vein that will be accessed. The patch is then plugged into a "controller" basically a battery area with an "on" switch. The battery delivers the Lidocaine to the injection site without the use of needles. In 10 minutes, the patient's vein area is numb and ready for a pain-free IV needlestick. This adds about $9 to the procedure, and for anyone who has had an IV placed (Braun says that there are 200 million done yearly), it is well worth it. However, the controller/battery unit does not allow for battery replacement and therefore the $50 unit must be thrown away after about 99 uses. That seems like a waste, and the company should be able to make enough revenue through the continued resale of the single-use patch that it could make a battery-changeable controller.

It was interesting to note how many of the vendors that attended this year's NTI made major product announcements. The NTI has historically been an important conference if for no other reason than because it is the last major show in the ICU product area each year until the following autumn. But with this year's gathering drawing 8,000 attendees and 450 vendors, it seems clear that this conference is growing in importance. And as the AACN and other nursing organizations continue to empower their members, the nursing/vendor interface unique to this meeting will continue to benefit both nurses and companies alike.