TUESDAY, March 6 (HealthDay News) -- Medication errors that occur during the course of a surgical procedure are three times more likely to harm a patient than errors committed during other types of hospital care, a new report shows.

Some 5 percent of such errors resulted in harm, said Diane Cousins, vice president of the department of Healthcare Quality and Information at the United States Pharmacopeia (USP), which conducted the survey. The nonprofit group sets safety standards for pharmaceutical care that are used worldwide.

The report analyzed 11,000 errors reported by 500 hospitals between 1998 and 2005. This is the largest known analysis of medical errors related to surgery, according to the USP.

Overall, there were about 500 harmful errors, including four fatalities, one of which involved a child.

Errors were most common in the operating room and were most likely to affect children. Almost 13 percent of pediatric errors resulted in harm, proportionately higher than any other group studied.

The most common medication errors in the surgery setting were receiving the wrong drug, the wrong amount of a drug, receiving the drug at the wrong time or not receiving the drug at all. Antibiotics and painkillers were most frequently found to be involved in errors.

The report focused on four parts of the "surgical continuum" -- outpatient surgery, the preoperative holding area, the operating room, and the post-anesthesia care unit.

There were 2,437 reported errors in outpatient surgery, 3.3 percent of them resulting in harm. In the pediatric population, 3.6 percent of errors resulted in harm, vs. 5.1 percent in adults and 5.1 percent in geriatric patients. Problems most commonly involved central nervous system medications and antimicrobials, with central nervous system drugs most likely to result in harm.

In the preoperative holding area, there were 779 errors, with 2.8 percent resulting in harm. For children, 4.2 percent of errors resulted in harm, compared to 7.1 percent for adults and 2.6 percent for elderly patients.

In the operating room, 3,773 errors were reported, 7.3 percent of which resulted in harm. Almost 17 percent of errors resulted in harm in children, 11.3 percent in adults and 10 percent in geriatric patients. Two of the errors caused or contributed to patient deaths.

Finally, in the post-anesthesia care unit, 3,260 errors occurred, of which 5.8 percent resulted in harm. Here, more than 20 percent of errors in children resulted in harm, compared with 8.7 percent in adults and 8.8 percent in elderly patients. Morphine drips and other patient-controlled analgesia machines were often involved in the most harmful errors. Tubing misconnections were also involved, as was an absence of reliable allergy information. Medication errors caused or contributed to two deaths.

Overall, Cousins said, the so-called "surgical continuum" was really a fragmented system in which numerous hand-offs of patients resulted in lack of coordination and errors.

The report included 47 recommendations, more than any other year. These included implementing strategies to improve communication among team members, designating a pharmacist to coordinate medication safety on behalf of a patient, working to ensure that medications are administered on time (particularly antibiotics) and issuing a call to manufacturers to provide ready-to-use sterile packaging, especially for drugs administered to children.