The CABG procedure is very common in the United States. Isolated CABG, refers to the performance of coronary artery bypass procedures only, that is, no other cardiac procedures were performed during this procedure, is very common in the United States. This is probably the most common invasive procedure for coronary conditions and is rivaled only by other non-invasive procedures such as percutaneous coronary intervention (PCI) in terms of prevalence. Statistics from the Society of Thoracic Surgeons (2006? ) reveals that approximately 141, 579 of these procedures were performed in 2004.
This represents approximately 65 percent of all coronary procedures performed that year nationally. Of course more CABG procedures are performed annually in conjunction with other procedures such as aortic valve replacement and mitral valve replacements. Thus CABG is even more widespread than the figures suggest since they do not take into account combined procedures. Hyperglycemia Hyperglycemia in patients undergoing cardiac procedures can result in negative patient outcomes by affecting mortality and morbidity. Hyperglycemia is defined as an elevated blood glucose level.
However there is not much consensus on the level of blood glucose that is considered acceptable. Lorenz et al. (2005) and Pennel et al. (2005) both consider blood glucose levels > 200 mg/dL as indication of hyperglycemia. Other researchers have suggested lower levels, even 110 mg/dL (Digman as cited in Pennel et al. , 2005) but for the purpose of this study the first figure will be used. Traditionally researchers studying the role of hyperglycemia in critical care patients, have tended to focus on those with a diagnosis of diabetes.
However, more and more researchers are realizing that hyperglycemia may develop in any patient undergoing cardiac procedures especially, regardless of their diabetic status (Lorenz et al. , 2005). In fact some patients with diabetes, reporting for surgical procedures, who had not previously been diagnosed with diabetes, may go undetected. Thus critical care nurses interacting with patients in such settings have to be careful to manage patients’ conditions very careful so that possible ill effects are avoided. Elevated blood glucose levels can have a significantly negative impact on patient outcomes (Pennel et al. , 2005).
Hyperglycemia has been linked to increased incidences of sternal wound infections, hospital acquired illnesses (Grey & Perdrizet, 2004), mortality (Krinsley, 2003) and other dangerous complications (Aragon, 2006). According to Lorenz et al. (2005) the presence of hyperglycemia elevates diabetic and non-diabetic patients’ risk of developing postoperative wound infections. Blood glucose levels > 200 mg/dL puts patients at a 78 percent to 85 percent higher chance of developing an infection. Hyperglycemia contributes to the development of infections by reducing “the intracellular bacteriocidal activity of leukocytes” (Lorenz et al.
, 2005) which further leads to decreased neutrophil functioning. The most dangerous type of infection is called deep sternal wound infection (DSWI). This type of infection results in high levels of morbidity and mortality in CABG patients. While patients with diabetes are at a higher risk of developing this type of complication, other patients such as those with obesity and connective tissue diseases, as well as others without any other co-morbidities, may be put at an increased risk when their blood glucose level is uncontrolled.
DSWI has been associated with heightened blood glucose within 48 hours of surgery. Increased length of stay in hospital has also been linked with elevated blood glucose levels in patients undergoing CABG procedures. According to the Society of Thoracic Surgeons (2006? ) the usual and average stay for patients undergoing isolated CABG procedures in 2005 was 7 and a half days. However Lorenz et al. (2005) has noted that patients who develop hyperglycemic complications post surgery may spend considerable more time in hospital.
They observed that patients who developed hyperglycemia and an infection spent on average between 16 and 32 days in hospital. Furthermore the hospital cost of caring for these patients is also elevated in the presence of hyperglycemia. Lorenz et al. (2005) also estimate that patients who develop these complications pay an additional $1,759 in costs for hospital care. They further estimate that the costs resulting from such infections total on average between $18,938 and $50, 986.