• Decrease font size
  • Return font size to normal
  • Increase font size
U.S. Department of Health and Human Services

MedSun: Newsletter #16, July 2007

  • Print
  • Share
  • E-mail

Newsletter #16, July 2007


FDA/MedSun Interested in Safety Issues in the Obese Patient Population

Print Item
E–mail Item

By Dolores Miranda,* Biomedical Engineer and Lead, FDA/CDRH Bariatric Workgroup

The prevalence of obesity has become a major health concern in the United States. Since 1960, the number of overweight and obese Americans has increased dramatically. Results from the 2003–2004 National Health and Nutrition Examination Survey indicated that 66.3 percent of adults in the United States were overweight, with 32.2 percent of these classified as obese, and 4.8 percent as morbidly, or extremely, obese.1

For adults, the National Institutes of Health defines overweight as a body mass index (BMI) of 25 to 29.9 kg/m2, obesity as a BMI of greater than or equal to 30 kg/m2, and morbid obesity as a BMI of greater than or equal to 40 kg/m2.2

According to the Healthcare Cost and Utilization Project, 126,240 patients were hospitalized for obesity as the principal diagnosis, and approximately 1.6 million were hospitalized for obesity as a coexisting condition in 2004. When obesity was the main diagnosis for hospital stays, 99.6 percent of the patients were morbidly obese. In contrast, when obesity was a secondary condition, only 33 percent had a diagnosis of morbid obesity.3

This patient population has unique characteristics and comorbidities that often make any medical procedure or surgery more complicated. Various medical or surgical interventions also may require use of medical devices exclusively designed for this population. Health care facilities are challenged by the dearth of specialized devices. For instance, obtaining diagnostic images in morbidly obese patients is difficult because many MRI and CT scanners have weight and size limits, and access to larger scanners may be limited. The quality of radiographic images is sometimes decreased due to the thickness the X-ray beam must penetrate.4 Additionally, managing morbidly obese patients places health care professionals at risk of injury.5 MedSun, the Medical Product Safety Network, has received several reports describing adverse events in the obese patient population. The following are summaries of three reports:

•The patient had a heart catheterization (cath) with a percutaneous transluminal coronary angioplasty/stent. The cath procedure was lengthy and difficult due to the patient’s obesity and the intervention required. The lengthy cath required the patient to experience prolonged radiation exposure. At the time of discharge, the patient had no complaint of skin irritation. Approximately 6 months later, the patient was seen at another hospital for a rectangular wound on his mid-thoracic back. This hospital reported a suspected radiation burn to the patient, possibly secondary to the catheterization that had been performed at the first hospital. The calculated radiation dose was estimated to be greater due to the patient’s weight and large chest, and the difficult location of the lesion (at the bifurcation site).

•While trying to position a transfer and repositioning mattress under a morbidly obese patient, two nurses held the device by the attached straps while four others attempted to move the patient with a draw sheet. During this activity, one of the straps broke, resulting in the patient’s falling backward to the floor and sliding into the wall. This event also caused the nurse’s head to collide with the wall.

•A patient in excess of 300 pounds was placed on a bedside commode. The patient attempted to rise from the commode but became entrapped. It took several staff to separate the patient from the commode. The patient sustained an 8-cm abrasion on the left-lateral thigh. This is the fourth instance in which an overweight patient was placed on a commode and the device broke or the patient became stuck and sustained minor injuries upon extraction.

These Bariatric Workgroup members also contributed to this article: Binita Ashar,* M.D., M.B.A.; Donna Engleman,** MedSun Program Manager; Diana Kaufman,* M.P.H.; Jill Marion,* Biomedical Engineer; and Suzanne Rich,* Senior Project Manager, R.N., M.A., CT.
*Center for Devices and Radiological Health (CDRH), Food and Drug Administration (FDA), U.S.
Department of Health and Human Services
**Social & Scientific Systems, Inc.

These adverse event reports submitted by MedSun’s facilities—along with reports from manufacturers and consumers, and the clinical community’s recognition of the challenges surrounding the care of morbidly obese patients—have prompted the Food and Drug Administration (FDA) to investigate current problems associated with the use of medical devices in the obese population. MedSun hopes to identify and characterize the adverse event reports received.

FDA analysts are interested in the following type of information in medical device reports:
•Could the patient’s size have caused or contributed to the adverse event? Is the patient overweight or extremely obese? If so, please describe the relationship of the patient’s obesity to the adverse event.
•Could the size of the device have caused or contributed to the adverse event?
•Could the patient’s size have affected the strength or durability of the device, possibly leading to failure of the device?
•Was the device selection limited due to the patient’s size?
•What are the patient’s weight and height?

We look forward to working with our MedSun hospitals to gain a better understanding of adverse events that occur in the obese population.

1 Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999–2004. JAMA, 2006. 295:1549–1555.
2 National Institutes of Health National Heart, Lung, and Blood Institute in cooperation with the National Institute of Diabetes and Digestive and Kidney Diseases. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults. NIH Publication No. 98-4083. September 1998.
3 Elixhauser A, and Steiner C. Obese patients in U.S. hospitals, 2004. HCUP Statistical Brief #20.
December 2006. Agency for Healthcare Research and Quality. Rockville, MD.
4 Uppot RN, Sahani DV, Hahn PF, Gervais D, Mueller PR. Impact of obesity on medical imaging and imageguided intervention. AJR, 2007. 188:433–440.
5 Nguyen NT, Moore C, Stevens CM, Chalifoux S, Mavandadi S, Wilson SE. The practice of bariatric
surgery at academic medical centers. J Gastrointest Surg. 2004 Nov;8(7):856–60.

Return to Top

Return to Medsun Home

UpFront / Device Safety: On Guard for Intra-aortic Balloon Pump Problems

Print Item
E–mail Item

By Kathleen M. Weil, R.N., B.S.N., M.S. From Nursing2007, Volume 37, Issue 7

A critically ill patient needed an intra-aortic balloon pump (IABP) to provide circulatory support.

When the pump’s helium tank was low, a nurse switched the pump off for 30 minutes to replace the tank.

At 2:30 a.m. the following day, the pump alarm sounded several times. The pump was shut off, and the patient was given heparin and blood products.

At 8:40 a.m., the physician removed the intra-aortic balloon (IAB) catheter without difficulty but found that no balloon membrane material was left on the catheter. The patient was immediately taken to the OR for surgery to remove the balloon membrane but later died.

What went wrong?
Intra-aortic balloon pump counterpulsation is frequently used as therapy for patients with refractory left ventricular heart failure or for other indications. Benefits of IABP therapy include increased cardiac output, coronary blood flow, and systemic perfusion pressure and decreased afterload and myocardial oxygen demands.

Letting an IAB remain dormant for longer than 15 minutes is hazardous, not only because the patient loses valuable cardiac support, but also because blood becomes trapped within the folds of the deflated balloon, promoting the formation of clots. The IAB in this case was allowed to remain dormant twice.

What precautions can you take?
As a nurse, you can help mitigate complications from IABP therapy. Suggested device management and precautions include the following:
•Frequently monitor the patient’s physiologic responses to IABP therapy such as cardiac output, cardiac index systemic vascular resistance, blood pressure, stroke volume, central venous pressure/right atrial pressure, and pulmonary capillary wedge pressure.
•Frequently check pump activity, helium level, driveline, and catheter.
•Replace empty helium tanks within 15 minutes—the sooner, the better. Keep extra
helium tanks nearby to minimize the time the IAB is dormant.
•Ensure that additional fully operational pumps are readily available in case of an emergency. If an alarm sounds, check the patient first, then the pump. Considered a high-priority alarm, a helium leak alarm indicates a potentially serious condition warranting immediate attention. If you can’t quickly identify the cause of the alarm, obtain another pump console. If the alarm continues to sound, notify the physician immediately. The balloon may have ruptured, requiring immediate removal.
•If pump operation can’t be restored within 15 minutes, the balloon becomes dormant. You must manually inflate and deflate the balloon optimally every 5 minutes; at a minimum, at least several times per hour. To reduce the risk of thrombus formation, continue this until a new pump is in place or the balloon is removed. Follow the IAB product instructions to check for blood in the driveline before starting manual inflation and deflation.
•Blood in the driveline or catheter can indicate that the IAB has ruptured. Notify the physician, who must remove a ruptured IAB immediately.
•Never inject air into the central (female luer fitting) lumen; you could introduce an air embolus into the patient’s circulation.
•If your patient has problems with either the IAB or the pump, quarantine the device after it’s removed and notify your biomedical engineering department so that the device can be returned to the manufacturer for examination and evaluation.
•Always follow the standards of clinical practice and your hospital’s policies and procedures when you care for a patient receiving IABP therapy.
The opinions and statements in this report are those of the author and may not reflect the views of the Department of Health and Human Services. Beverly Albrecht Gallauresi, R.N., B.S., M.P.H., who coordinates Device Safety, is a nurse-consultant at the Center for Devices and Radiological Health at the Food and Drug Administration in Rockville, Maryland.
Kathleen M. Weil of Social & Scientific Systems, Inc., is a nurse-consultant specializing in cardiovascular devices at the FDA’s Center for Devices and Radiological Health.

Return to Top

Return to Medsun Home

Two MedSun Sites Named by Institute for Pediatric Innovation to Consortium of Leading Children’s Hospitals

Print Item
E–mail Item

Nonprofit Organization Devoted to Developing “Products Optimized for Children’s Health Care”

Two MedSun sites have been named members of a consortium of leading children’s hospitals by the Institute for Pediatric Innovation (IPI), a recently formed nonprofit organization that focuses on improving health care for children by developing medical products specifically designed for pediatric patients.

Lucile Packard Children’s Hospital in Palo Alto, California, and Children’s Mercy Hospitals and Clinics in Kansas City, Missouri, are two of the three founding members of the Consortium. The Consortium hospitals will collaborate with IPI, which is based in Cambridge, Massachusetts, in identifying priorities in clinical care and work to redesign medical devices and reformulate drugs for children.

Designing pediatric medical devices has long been recognized as a challenge. Although some products are tailored to meet the needs of children, others are adapted from adult applications. “Because children make up such a small percentage of the total population needing medical care, their needs are often overlooked in any national health care discussion. This new consortium will bring together world-class pediatric specialists, pediatric nurses, and allied health professionals who are national leaders in their fields to help ensure that children’s needs remain in the spotlight and receive the attention they deserve,” according to Randall L. O’Donnell, Ph.D., president and
CEO of Children’s Mercy Hospitals and Clinics, whose comments were issued for IPI’s launch in

Additional Information:

To learn more about IPI, go to its Web site at

Return to Top

Return to Medsun Home

Pennsylvania’s Patient Safety Authority Releases Data on Wrong-Site Surgeries and Results From a Hospital Pharmacy Computer System Safety Study

Print Item
E–mail Item

The June 2007 Patient Safety Advisory published by the Pennsylvania Patient Safety Authority (PSA) presented data on wrong-site surgery indicating that in a 30-month period—June 2004 through December 2006—PSA received reports of 427 near misses and serious events of wrongsite surgeries. Of those, 253 were near misses or did not reach the patient. Of the wrong-site surgeries, 69 percent were on the wrong side, 14 percent were on the wrong body part, 9 percent were the wrong procedure, and 8 percent were on the wrong patient. The most common sites for wrong-site surgery were extremities, the eyes, and the spine. The most common wrong-site procedures were orthopedic and ophthalmologic surgeries.

Risk factors for wrong-site surgery include multiple procedures and/or multiple surgeons; communication breakdowns; time pressures; incomplete preoperative assessments; and organizational cultural factors unconducive to promoting teamwork, such as an attitude that surgeons’ decisions should never be questioned. In many cases, the patient or a family member was responsible for providing information that prevented the wrong-site surgery.

Dr. Stan Smullens, chief medical officer of the Jefferson Health System and vice president of the PSA Board of Directors stated, “To be frank, wrong-site surgeries in Pennsylvania should never occur. However, every other day in Pennsylvania we have a report of a wrong-site surgery being caught either before or after the start of an operation. However, we are not alone. Wrong-site surgeries are no more common in Pennsylvania than they are in other States. We also have in common with other States the problem of trying to fix them.” This summer, PSA will begin to gather comprehensive information on which to base new, more effective guidance to help facilities prevent wrong-site surgeries.

The PSA May 2007 Supplementary Advisory featured results from the Pennsylvania Patient Safety Reporting System assessment by a Workgroup on Pharmacy Computer System Safety of safety features and capabilities of hospital pharmacy computer systems. Findings from this study, which was carried out on a voluntary basis by creating fictitious patient profiles and 18 unsafe medication orders in 30 Pennsylvania hospitals, showed that the pharmacy computer systems failed to identify harmful interactions and overdoses and also allowed users to override serious warnings that put patients at risk.

“Many of the systems performed poorly when tested with specific unsafe medication orders to assess their ability to detect serious or fatal errors they reported to us. None of the 30 systems tested in the workgroup [was] able to detect all unsafe orders presented in the field test, and one system only detected one unsafe order,” said Mike Doering, PSA interim executive director. Doering encourages all facilities to test their pharmacy computer systems more frequently to ensure they are using the error-catching features to their full potential and to ensure that the systems are capable of preventing such errors.

“New or updated technology is part of the solution to reducing the risk of error, but there is always a danger of relying too much on technology as a safety net,” added Doering. “Pharmacists should not rely on this tool alone to detect potentially harmful medication errors. They should work with staff and communicate problems on a regular basis to prevent future errors.”

To read the full articles on these investigations, go to http://www.psa.state.pa.us, click on “Advisories and Related Resources,” and then scroll down to “Doing the ‘Right’ Things To Correct Wrong-Site Surgery” in the June 2007 Advisory, and “Results of the PA-PSRS Workgroup on Pharmacy Computer System Safety” in the May 2007 Supplementary Advisory.

Additional Information:

Doing the ‘Right’ Things To Correct Wrong-Site Surgery

Return to Top

Return to Medsun Home

Updated July 1, 2007

Return to MedSun: Medical Product Safety Network