The number of patients admitted by U.S. hospitals to treat complications resulting from surgery or medical treatment increased from 305,000 in 1993 to 452,000 in 2003, according to HHS' Agency for Healthcare Research and Quality.

Complications from surgery can include postoperative infections. Complications from medical care can result from extended bed rest and may include lung embolism, dangerously low blood pressure, or collapsed lung.

The number of cases of surgical or medical care complications admitted through hospital emergency departments rose from 98,000 in 1993 (32 percent of all cases) to 211,000 (47 percent of all cases) in 2003.

The average cost to hospitals for treating surgical or medical complications increased from $6,840 in 1993 to $9,600 in 2003.

These statistics are from the Nationwide Inpatient Sample, part of AHRQ's Healthcare Cost and Utilization Project (HCUP). This project comprises a family of databases and related software tools developed through a federal-state-industry partnership and sponsored by AHRQ. HCUP includes the largest set of publicly available databases on all patients in the United States, regardless of type of insurance or whether the patients had insurance.

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