The incidence of deep vein thrombosis after general surgical operations seems to be low when preventive steps are taken, while most cases that do occur are diagnosed in the inpatient setting and most are associated with catheter use, according to a report on the website of the Archives of Surgery.
DVT occurs in up to 40% of general surgery patients with an associated death risk of 1% without prophylaxis, according to background information in the article. Historically, some surgeons have been resistant to using anticoagulant medications that protect against DVT because of concern about bleeding, although recent research suggests that prevention is associated with significant reductions in DVT and a low rate of major bleeding.
“Few data exist regarding the specifics of DVT formation when general surgical patients receive adequate prophylaxis,” the authors wrote.
Brian R. Smith, MD, and colleagues in the Department of Surgery at University of California-Irvine Medical Center in Orange reviewed data from the National Surgical Quality Improvement Program from January 2008 to December 2009. The researchers evaluated medical records to assess patient characteristics and demographics, whether a central catheter was in place, the location of DVT, the time of diagnosis from the index operation, whether any DVT were associated with pulmonary embolism and how many deaths occurred.
During the study period 2,189 patients underwent general operations (including surgeries of the pancreas, esophagus, stomach, intestines, colon and rectum, as well as other body parts) and 35 (1.6%) developed DVT. Most cases (94.3%) of DVT were detected because patients experienced DVT symptoms; the rest were found through routine screening. Similar numbers of patients developed upper-extremity DVT (40%) or lower-extremity DVT (45.7%), and 14.3% developed DVT in both areas.
DVT was diagnosed an average of 8.6 days after the operation, and in 83% of cases was diagnosed in the inpatient setting. DVT associated with catheters occurred in 60% of patients. Other underlying health problems were noted in 62.9% of patients, including pulmonary embolism in 11.4%. At 30 days, the death rate was 14.2%. The researchers reported an average 93% compliance with prophylaxis criteria during the study period.
“The incidence of DVT after general surgical operations is low, with most cases diagnosed as inpatients,” the authors wrote. “With more than half of DVTs being caused by central catheters, efforts toward DVT prevention should include closer scrutiny to the need for central catheters, including limiting the duration of central catheters, and consideration of the added use or perhaps higher dose of anticoagulation when central catheters are present.”
To view the study data, visit http://archsurg.ama-assn.org/cgi/content/short/archsurg.2011.204.