Chapter 3. Patient Safety

Importance

Mortality
Number of Americans who die each year from medical errors (1999 est.)	44,000-98,000 (Kohn, et al., 2000)
Prevalence
Rate of adverse events for hospitalized patients (annual estimates)	2.9%-3.7% (Kohn, et al., 2000)
Rate of adverse drug reactions during hospital admissions (annual estimates)	1.9 million (Lucado, et al., 2011)
Rate of adverse drug events among Medicare beneficiaries in ambulatory settings	50 per 1,000 person-years (Gurwitz, et al., 2003)
Cost
Cost attributable to medical errors (2008)	$19.5 billion (Shreve, et al., 2010)
Total cost per error (2008)	$13,000 (Shreve, et al., 2010)
Annual cost attributable to surgical errors (2008)	$1.5 billion (Encinosa & Hellinger, 2008)

Measures

The Institute of Medicine (IOM) defines patient safety as "freedom from accidental injury due to medical care or medical errors" (Kohn, et al., 2000). In 1999, the IOM published To Err Is Human: Building a Safer Health System, which called for a national effort to reduce medical errors and improve patient safety (Kohn, et al., 2000). In response to the IOM's report, President George W. Bush signed the Patient Safety and Quality Improvement Act of 2005 (Patient Safety Act).ⁱ The act was designed to spur the development of voluntary, provider-driven initiatives to improve the quality, safety, and outcomes of patient care. The Patient Safety Act addresses many of the current barriers to improving patient care.

Central to this effort is the ability to measure and track adverse events. Measuring patient safety is complicated by difficulties in assessing and ensuring the systematic reporting of medical errors and adverse events. All too often, adverse event reporting systems are laborious and cumbersome. Health care providers may also fear that if they participate in the analysis of medical errors or patient care processes, the findings may be used against them in court or harm their professional reputations. Many factors limit the ability to aggregate data in sufficient numbers to rapidly identify prevalent risks and hazards in the delivery of patient care, their underlying causes, and practices that are most effective in mitigating them. These include difficulties aggregating and sharing data confidentially across facilities or State lines.

To Err Is Human does not mention race or ethnicity when discussing the problem of patient safety, and data are limited. Any differences that suggest patient race or ethnicity might influence the risk of experiencing a patient safety event must be investigated to better understand the underlying reasons for any differences before the differences can be eliminated.

Despite these limitations, a more complete picture of patient safety is emerging. In recent years, progress has been made in raising awareness, developing reporting systems, and establishing national data collection standards. Examining patient safety using a combination of administrative data, medical record abstraction, spontaneous adverse event reports, and patient surveys allows a more robust understanding of what is improving and what is not. Still, data remain incomplete for a comprehensive national assessment of patient safety (Aspden, et al., 2004).

To increase access to high-quality, affordable health care for all Americans, one of the broad aims of the National Quality Strategy (NQS) is providing better care. One way to advance this aim is by focusing on the priority of making care safer by reducing harm caused during the delivery of care. This priority has great potential for rapidly improving health outcomes and increasing the effectiveness of care for all populations. The NQS states that health care providers should aim to reduce the rates of care-related injury to zero whenever possible and should strive to create a system that reliably provides high-quality health care for everyone.

The Partnership for Patients was created to improve the quality, safety, and affordability of health care for all Americans. One of the goals of this partnership is to:

• Keep patients from getting injured or sicker.
  • By the end of 2013, preventable hospital-acquired conditions would decrease by 40% compared with 2010. Achieving this goal would mean approximately 1.8 million fewer injuries to patients with more than 60,000 lives saved over 3 years.

Achieving the goals of the partnership will save lives and prevent injuries to millions of Americans. In addition, up to $35 billion dollars could be saved across the health care system, including up to $10 billion in Medicare savings over the next 3 years. Over the next 10 years, it could reduce cost to Medicare by about $50 billion and result in billions more in Medicaid savings. This will help put our Nation on the path toward a more sustainable health care system.

The National Healthcare Disparities Report (NHDR) has tracked a growing number of patient safety measures. Organized around the Partnership for Patients' priority of safety, the 2011 NHDR presents the following measures that relate to the goal to keep patients from getting injured or sicker:

• Healthcare-associated infections (HAIs):
  • Appropriate care among surgical patients.
  • Appropriate timing of antibiotics among surgical patients.
  • Postoperative sepsis.
• Adverse events:
  • Ambulatory care visits due to adverse effects of medical care.
  • Mechanical adverse events associated with central venous catheters.
  • Postoperative respiratory failure.
• Preventable and premature mortality rates:
  • Deaths following complications of care.
  • Inpatient pneumonia deaths.

Findings

Healthcare-Associated Infections

Infections acquired during hospital care (nosocomial infections) are one of the most serious patient safety concerns. They are the most common complication of hospital care (Thomas, et al., 2000). An estimated 1.7 million HAIs occur each year in hospitals, leading to about 100,000 deaths. The most common infections are urinary tract, surgical site, and bloodstream infections (Klevens, et al., 2007).

A specific medical error cannot be identified in most cases of HAIs. However, better application of evidence-based preventive measures can reduce HAI rates within an institution.

Prevention: Appropriate Care Among Surgical Patients

To reduce postoperative complications and improve surgical care, several preventive practices need to be followed. Administering and discontinuing recommended antibiotics at the right time, ensuring good glycemic control, using appropriate hair removal methods, continuing beta blocker therapy when appropriate, and administering appropriate thromboembolism prophylaxis can reduce morbidity and mortality. The 2011 National Healthcare Quality Report (NHQR) and 2011 NHDR track a Surgical Care Improvement Project (SCIP) composite that includes eight components of the Reporting Hospital Quality Data for Annual Payment Update.

The SCIP composite includes prophylactic antibiotic received within 1 hour prior to surgical incision (SCIP Inf-1), recommended prophylactic antibiotic for surgical patients (SCIP Inf-2 ), prophylactic antibiotics discontinued with 24 hours after surgery end time (SCIP Inf-3), cardiac surgery patients with controlled postoperative blood glucose (SCIP Inf-4), surgery patients with appropriate hair removal (SCIP Inf-6), surgery patients on beta blocker therapy prior to arrival who received a beta blocker during the perioperative period (SCIP Card-2), surgery patients with recommended venous thromboembolism prophylaxis ordered (SCIP VTE-1 ), and surgery patients who received appropriate venous thromboembolism prophylaxis within 24 hours prior to surgery to 24 hours after surgery (SCIP VTE-2).

Figure 3.1. Adult surgery patients who received appropriate care, by gender and race/ethnicity, 2009

   
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Key: AI/AN = American Indian/Alaska Native.
Source: Centers for Medicare & Medicaid Services, Medicare Quality Improvement Organization Program, 2009.
Denominator: Hospitalized patients having surgery.

• In 2009, 87% of female surgery patients and 85% of male surgery patients received appropriate care (Figure 3.1).
• More than 86% of White patients received appropriate surgical care. Nearly 86% of Black patients received appropriate surgical care, and 85% of Hispanic patients, 84% of Asian patients, and 82% of American Indian or Alaska Native (AI/AN) patients received appropriate surgical care.
• The 2009 top 5 State achievable benchmark was 91%.ⁱⁱ

Also, in the NHQR:

• Eighty-seven percent of patients under age 65, 86% of patients ages 65-74, 85% of patients ages 75-84, and 84% of patients age 85 and over received appropriate surgical care.

Prevention: Appropriate Timing of Antibiotics Among Surgical Patients

Wound infection following surgery is a common HAI. Hospitals can reduce the risk of surgical site infection by ensuring that patients get the right antibiotics at the right time on the day of their surgery. Surgery patients who get antibiotics within 1 hour before their operation are less likely to get wound infections than those who do not receive antibiotics within 1 hour before surgery.

Getting an antibiotic earlier than 1 hour before surgery or after surgery begins is not as effective. However, taking antibiotics for more than 24 hours after routine surgery is usually unnecessary and can increase the risk of side effects, such as antibiotic resistance and serious types of diarrhea. Among adult Medicare patients having surgery, the NHDR tracks receipt of antibiotics within 1 hour prior to surgical incision, discontinuation of antibiotics within 24 hours after end of surgery, and a composite of these two measures.

Figure 3.2. Adult surgery patients who received appropriate timing of antibiotics: Overall composite, by race/ethnicity and gender, 2005-2009

  
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Key: AI/AN = American Indian or Alaska Native.
Source: Centers for Medicare & Medicaid Services, Medicare Quality Improvement Organization Program, 2005-2009.
Denominator: Hospitalized patients having surgery.
Note: Populations not specifically noted as Hispanic are non-Hispanic.

• The overall percentage of adult surgery patients who received appropriate timing of antibiotics improved from 2005 to 2009 (75% to 95%; Figure 3.2). Significant improvement was also seen among all racial, ethnic, and gender groups during this period.
• From 2005 to 2009, Whites improved from 75% to 95%, Blacks improved from 75% to 94%, and Asians improved from 71% to 94%. The percentage of patients receiving appropriate timing of antibiotics increased from 70% to 94% for Hispanics and from 77% to 93% for AI/ANs.
• The 2008 top 5 State achievable benchmark was 95%.ⁱⁱⁱ At the current 5% annual rate of increase, this benchmark could be attained overall in less than 1 year. All ethnic, racial, and gender groups could also attain the achievable benchmark in less than 1 year.

Also, in the NHQR:

• The percentage of adult surgery patients who received appropriate timing of antibiotics improved for all age groups from 2005 to 2009.

Outcome: Postoperative Sepsis

Sepsis, a severe bloodstream infection, can occur after surgery. In a recent study, postoperative sepsis occurred in 5% ofemergency surgery patients and 2% of elective surgery patients (Moore, et al., 2010). A recent study revealed that higher rates of infection and higher risk of acute organ dysfunction both contribute to higher sepsis rates among Blacks compared with Whites (Mayr, et al., 2010). Rates can be reduced by giving patients appropriate prophylactic antibiotics 1 hour prior to surgical incision.

Figure 3.3. Postoperative sepsis per 1,000 elective-surgery discharges with an operating room procedure, by race/ethnicity and insurance status, 2008

   
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Source: Agency for Healthcare Research and Quality (AHRQ), Center for Delivery, Organization, and Markets, Healthcare Cost and Utilization Project, State Inpatient Databases disparities analysis file, 2007, and AHRQ Quality Indicators, modified version 4.1.
Denominator: All elective hospital surgical discharges, age 18 and over, with length of stay of 4 or more days, excluding patients admitted for infection, patients with cancer or immunocompromised states, patients with obstetric conditions, and admissions specifically for sepsis.
Note: For this measure, lower rates are better. White, Black, and Asian are non-Hispanic. Rates are adjusted by age, gender, age-gender interactions, comorbidities, and diagnosis-related group clusters.

• In 2008, Whites had a significantly lower rate of postoperative sepsis than Blacks and Hispanics (Figure 3.3). People with private insurance had a significantly lower rate of postoperative sepsis than people with Medicare and Medicaid, but people who were uninsured or self-pay had a significantly lower rate than all other groups.

Also, in the NHQR:

• In 2008, surgery patients ages 18-44 and 45-64 had significantly lower rates of postoperative sepsis than those age 65 and over (11 and 12 per 1,000 hospital discharges, respectively, compared with 18 per 1,000 hospital discharges).

Adverse Events

Adverse effects of medical care can arise from medical and surgical procedures as well as from drug reactions. Although patient safety initiatives are predominantly focused on inpatient hospital events, adverse effects of medical care are much more commonly treated at visits to outpatient settings, with more than 12 million such visits occurring annually. Providers treating adverse events in outpatient settings may be located in physician offices, hospital outpatient departments, and hospital emergency departments. Events treated in ambulatory settings may be less severe than those occurring in inpatient settings.

Some adverse events, such as known side effects of appropriately prescribed medications, may be unavoidable, while others may be considered medical errors. Although the following measure does not distinguish between the two types of events, it provides an overall sense of the burden these events place on the population.

Outcome: Ambulatory Care Visits Due to Adverse Effects of Medical Care

Figure 3.4. Ambulatory medical care visits due to adverse effects of medical care per 1,000 people, by race and gender, 2006-2009

  

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Source: Centers for Disease Control and Prevention, National Center for Health Statistics, National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, 2006-2009.
Denominator: U.S. Census Bureau estimated civilian noninstitutionalized population on July 1, 2007, and July 1, 2008.
Note: For this measure, lower rates are better. Ambulatory care includes visits to office-based physicians, hospital outpatient departments, and hospital emergency departments.

• From 2006-2007 to 2008-2009, the rate of ambulatory care visits due to adverse effects of medical care was significantly higher for females compared with males (Figure 3.4).
• During this same period, there were no statistically significant differences between Whites and Blacks in the rate of ambulatory care visits due to adverse effects of medical care.

Also, in the NHQR:

• From 2006-2007 to 2008-2009, the rate of ambulatory care visits due to adverse effects was significantly higher for patients ages 18-44 than for patients ages 0-17. Rates, however, were significantly lower for patients ages 18-44 than for patients ages 45-64 and 65 and over.

Outcome: Mechanical Adverse Events Associated With Central Venous Catheters

Some patients need a central venous catheter inserted into a major vein in the neck, chest, or groin so that providers can administer medication or fluids, obtain blood for tests, and take cardiovascular measurements. Patients who require a central venous catheter tend to be severely ill. The placement and use of these catheters can result in mechanical adverse events, including bleeding; hematoma; perforation; pneumothorax; air embolism; and misplacement, occlusion, shearing, or knotting of the catheter.

Figure 3.5. Composite: Mechanical adverse events associated with central venous catheter placement, by race and gender, 2005-2009

  

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Source: Centers for Medicare & Medicaid Services, Medicare Patient Safety Monitoring System (MPSMS), 2005-2009.
Denominator: Adult hospitalized Medicare fee-for-service discharges from the MPSMS sample with central venous catheter placement.
Note: For this measure, lower rates are better. Mechanical adverse events include allergic reaction to the catheter, tamponade, perforation, pneumothorax, hematoma, shearing off of the catheter, air embolism, misplaced catheter, thrombosis or embolism, knotting of the pulmonary artery catheter, and certain other events. Data not available for 2008.

• From 2005 to 2009, there was no statistically significant change in the overall rate of medical adverse events associated with central venous catheter placement (data not shown). Whites and both genders also had no statistically significant change. Blacks, however, had a significant increase in the rate of medical adverse events associated with central venous catheter placement (Figure 3.5).

Also, in the NHQR:

• From 2005 to 2009, there were no statistically significant differences in adverse events associated with central venous catheter placement between patients under age 65 and patients of any other age group in any year.

Outcome: Postoperative Respiratory Failure

Respiratory failure is not uncommon after surgery and may necessitate reintubation or prolonged mechanical ventilation. Causes include oversedation, exacerbation of underlying cardiovascular or respiratory conditions, and ventilator-associated pneumonia. Although some cases of respiratory failure cannot be prevented, close attention to risk factors can reduce rates.

Figure 3.6. Postoperative respiratory failure per 1,000 elective-surgery discharges after an operating room procedure, by race/ethnicity and income area, 2004-2008

  

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Key: API = Asian or Pacific Islander.
Source:  Agency for Healthcare Research and Quality (AHRQ), Center for Delivery, Organization, and Markets, Healthcare Cost and Utilization Project, State Inpatient Databases disparities analysis file, 2007, and AHRQ Quality Indicators, modified version 4.1.
Denominator: All elective hospital surgical discharges age 18 and over, excluding patients with respiratory disease, circulatory disease, neuromuscular disorders, obstetric conditions, selected surgeries for craniofacial anomalies, and secondary procedure of tracheostomy before or after surgery or as the only procedure.
Note: For this measure, lower rates are better. White, Blacks, and APIs are non-Hispanic. Rates are adjusted by gender, age-gender interactions, comorbidities, and diagnosis-related group clusters.

• From 2004 to 2008, the rate of postoperative respiratory failure was significantly lower for Whites than for Blacks and Hispanics (Figure 3.6).
• During this same period, the rate of postoperative respiratory failure decreased for Blacks and Hispanics.

Also, in the NHQR:

• From 2004 to 2008, the rate of postoperative respiratory failure for patients ages 18-44 remained significantly lower than for all other age groups.

Preventable and Premature Mortality Rates

Outcome: Deaths Following Complications of Care

Many complications that arise during hospital stays cannot be prevented. However, rapid identification and aggressive treatment of complications may prevent these complications from leading to death. The indicator "deaths following complications of care," also called "failure to rescue," tracks deaths among patients whose hospitalizations are complicated by pneumonia, thromboembolic events, sepsis, acute renal failure, gastrointestinal bleeding or acute ulcer, shock, or cardiac arrest (AHRQ, 2003).

Figure 3.7. Deaths per 1,000 discharges with complications potentially resulting from care (failure to rescue), ages 18-89, by race/ethnicity and area income, 2004-2008

  

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Source:  Agency for Healthcare Research and Quality (AHRQ), Center for Delivery, Organization, and Markets, Healthcare Cost and Utilization Project, State Inpatient Databases disparities analysis file, 2007, and AHRQ Quality Indicators, modified version 4.1.
Denominator: Patients ages 18-89 years from U.S. community hospitals whose hospitalizations are complicated by pneumonia, thromboembolic events, sepsis, acute renal failure, gastrointestinal bleeding or acute ulcer, shock, or cardiac arrest.
Note: For this measure, lower rates are better. Whites, Blacks, and Asians are non-Hispanic. Rates are adjusted by age, gender, comorbidities, and diagnosis-related group clusters.

• From 2004 to 2008, the rate of deaths following complications of care declined from 138 to 122 per 1,000 admissions of adults ages 18-89 (data not shown). A significant decrease was also seen among all income groups during the same period (Figure 3.7).
• During this period, there were no statistically significant changes in the gap between the failure to rescue rate of high-income patients and patients of other income groups.

Also, in the NHQR:

• From 2004 to 2008, the rate of death following complications of care was significantly lower for patients ages 18-44 than for patients ages 45-64 and 65-89. During this same period, females had a significantly lower rate than males of death following complications.

Outcome: Inpatient Pneumonia Deaths

Measuring quality of care is a key component in improving care. One measure of quality is the 30-day hospital mortality rate for conditions such as pneumonia. National 30-day mortality rates due to pneumonia are not currently available for reporting, so the in-hospital mortality rates per 1,000 hospital admissions with pneumonia are reported here. About two-thirds of patients who die within 30 days of hospital admission die in the hospital, and the correlation between hospital-level inpatient and 30-day mortality is high (Rosenthal, et al., 2000).

Figure 3.8. Deaths per 1,000 hospital admissions with pneumonia as principal diagnosis, age 18 and over, by race/ethnicity and area income, 2004-2008

   

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Key: API = Asian or Pacific Islander.
Source: Agency for Healthcare Research and Quality (AHRQ), Center for Delivery, Organization, and Markets, Healthcare Cost and Utilization Project, State Inpatient Databases disparities analysis file, 2007, and AHRQ Quality Indicators, modified version 4.1.
Denominator: All discharges age 18 and over with principal diagnosis code of pneumonia, excluding patients transferred to another short-term hospital and obstetric and neonatal admissions.
Note: For this measure, lower rates are better. Whites, Blacks, and APIs are non-Hispanic. Rates are adjusted by age, gender, age-gender interactions, comorbidities, major diagnostic category (MDC), diagnosis-related group (DRG), and transfers into the hospital.  When reporting is by age, the adjustment is by gender, comorbidities, MDC, DRG, and transfers into the hospital.

• From 2004 to 2008, the overall inpatient pneumonia mortality rate decreased from 54 per 1,000 admissions to 36 per 1,000 admissions (data not shown). A significant decrease was also seen among all racial/ethnic and income groups during the same period (Figure 3.8).
• During the same period, Blacks and Hispanics had a significantly lower inpatient pneumonia mortality rate than Whites.
• The 2007 top 4 State achievable benchmark was 28 per 1,000 hospital admissions.^iv At the current rate of improvement, this benchmark could be attained in less than 2 years.
• Rates of improvement varied by race and ethnicity. Blacks and Hispanics could attain the benchmark in just under 1 year, while Whites and Asians could attain the benchmark in about 2 years.

Also, in the NHQR:

• From 2004 to 2008, the inpatient pneumonia mortality rate of patients ages 18-44 was significantly lower than for patients ages 45-64 and 65 and over. During this same period, females had a significantly lower inpatient pneumonia mortality rate than males.

References

Aspden P, Corrigan J, Wolcott J, et al. Patient safety: achieving a new standard of care. Washington, DC: Institute of Medicine, Committee on Data Standards for Patient Safety; 2004.

Encinosa WE, Hellinger FJ. The impact of medical errors on 90-day costs and outcomes: an examination of surgical patients. Health Serv Res 2008 Dec;43(6):2067-85. Epub 2008 Jul 25.

Guide to Patient Safety Indicators version 3.1. Rockville, MD: Agency for Healthcare Research and Quality; 2003.

Gurwitz JH, Field TS, Harrold LR, et al. Incidence and preventability of adverse drug events among older persons in the ambulatory setting. JAMA 2003 Mar 5;289(9):1107-16.

Klevens RM, Edwards JR, Richards CL, et al. Estimating health care-associated infections and deaths in U.S. hospitals, 2002. Public Hlth Rep 2007;122:160-6.

Kohn L, Corrigan J, Donaldson M, eds. To err is human: building a safer health system. Washington, DC: Institute of Medicine, Committee on Quality of Health Care in America; 2000.

Lucado J, Paez K, Elixhauser A. Medication-related adverse outcomes in U.S. hospitals and emergency departments, 2008. HCUP Statistical Brief #109. Rockville, MD: Agency for Healthcare Research and Quality; April 2011. Available at: http://www.hcup-us.ahrq.gov/reports/statbriefs/sb109.jsp.

Mayr FB, Yende S, Linde-Zwirble WT, et al. Infection rate and acute organ dysfunction risk as explanations for racial differences in severe sepsis. JAMA 2010 Jun 23;303(24):2495-2503.

Moore LJ, Moore FA, Todd SR, et al. Sepsis in general surgery: the 2005-2007 National Surgical Quality Improvement Program perspective. Arch Surg 2010 Jul;145(7):695-700.

Rosenthal GE, Baker DW, Norris DG, et al. Relationships between in-hospital and 30-day standardized hospital mortality: implications for profiling hospitals. Health Serv Res 2000 Mar;34(7):1449-68.

Shreve J, Van Den Bos J, Gray T, et al. The economic measurement of medical errors. Schaumberg, IL: Society of Actuaries/Milliman; 2010.

Thomas EJ, Studdert DM, Burstin HR, et al. Incidence and types of adverse events and negligent care in Utah and Colorado. Med Care 2000;38:261-71.

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^i. Patient Safety and Quality Improvement Act of 2005, 42 U.S.C. 299b-21 to 299b-26.
^ii. The top 5 States that contributed to the achievable benchmark are Delaware, Maine, Massachusetts, New Hampshire, and Vermont.
^iii. The top 5 States that contributed to the achievable benchmark are Hawaii, Maine, New Hampshire, South Dakota, and Vermont.
^iv. The top 4 States that contributed to the achievable benchmark are Arizona, Colorado, Maryland, and Michigan.

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