This analysis has demonstrated that patients, after adjustment for age, gender, race and comorbidities, had increased infectious complications after in-hospital delay for all elective high volume procedures evaluated. An in-hospital delay of as few as two days is associated with increase infectious complications, particularly of pneumonia and UTI for elective CABG. For elective thoracic procedures, pneumonia was seen to dramatically increase if patients were delayed greater than six days. Factors associated with in-hospital delay included advanced age, female gender, minority status, and comorbidities including congestive heart failure, chronic pulmonary disease and renal failure. The development of complications may be multifactorial, yet in-hospital delay was significantly associated with the development of infectious complications and increased hospital resource utilization.
The concept that surgical infections are increased with in-hospital delay has been described, yet few population level data exist. 1, 7–8
It has been reported from single center series that increased overall length of stay in the postoperative period is associated with increased nosocomial infections. Cruse et al. described that advanced age of the patient, prolonged preoperative hospitalization, and long operations were associated with an increase in the rate of infection of surgical wounds.7
Saez-Castillo et al. also demonstrated utilizing an asymmetric logit that length of stay, the existence of a preoperative stay, and obesity were the main risk factors for a nosocomial infections.1
As well, a single center study performed almost two decades ago evaluated 449 patients undergoing a variety of surgical procedures. They suggested that lengthening the preoperative stay may increase wound infections and they found the strongest association between preoperative stay and nosocomial infection.8
Multiple authors have elucidated the significant cost of infection and that health care-associated infections impose substantial clinical and economic costs.9–10
This analysis has demonstrated that for all index procedures evaluated, delay was associated with significant cost increases. These increased costs were greater than would be expected from the increased room charges alone. Sparling et al. used a matched cohort design to compare costs and demonstrated that length of stay was increased by 10.6 days and costs were increased by $27,288 for each patient with a potentially preventable surgical site infection.10
Healthcare-associated infections also have a relevant socioeconomic impact. In a European study, the overall estimated yearly costs vary between 3.5 billion Euros in the United States to 1.3 billion Euros in England. Surgical site and bloodstream infections were found to be the most costly types of infections, followed by lower respiratory tract and urinary tract infections.11
Suggested methods to prevent these complications have been compliance to best practices and structural process of care within hospitals. 12–16
Fry et al. has stated that infection after surgery continues to be a major source of morbidity and expense despite efforts with educational programs, guidelines, and hospital-based policies and procedures. This study concluded that the adoption of a culture dedicated to quality control through better information technology and data-driven initiatives to achieve improved clinical outcomes from infectious complications in surgery.3
From this analysis, only 53% of elective CABG procedures were performed on the day of admission. It is plausible that future data driven methodologies implementing guidelines to decrease in-hospital delay prior to elective procedures may improve outcomes and may decrease overall rates of infection.
This study has several limitations. Administrative data originally were intended primarily for reimbursement, although validation of the use of administrative data for research purposes has been performed.17–18
In addition, the potential for inclusion bias based on limited coding schemes for the many clinical entities cannot be entirely excluded. Due to the large number of hospitals reporting data and the even larger number of coders entering data it is difficult to account for potential coding errors. As well, the NIS does not include patients in military hospitals or VA medical centers. It has been suggested that length of preoperative stay is a surrogate for severity of illness and co-morbid conditions19
, although this was adjusted for in the analysis. As well, the use of coding present-on-admission coding would be useful to discern procedures occurring before elective surgeries, but these codes are not currently available. Furthermore, this study contains only elective procedures and no information regarding infections present on admission is available, yet there is the possibility that elective admissions developed an emergency procedure during their hospitalization and this cannot be discerned from the current dataset. The use of smaller cohorts may offer further refined clinical information regarding infectious complications, although these data are generalizable to the nation and offer insight into national rates of infectious complications after in-hospital delay of elective index surgeries.
In conclusion, this analysis has shown on a population level that in-hospital delay is significantly associated with a negative impact on patients with regard to infectious complications and mortality. The rates of all nosocomial infections after CABG, lung and colon resection increased significantly when a procedure encountered in-hospital delay after admission. In-hospital delay before elective surgery evokes a significant increase in infectious complications for high volume cases and subsequently adds significantly to the cost of healthcare. After adjustment for age, gender, race and comorbidities a delay of as little as one day increased rates of infection for all index cases evaluated, and this association had greater impact as the delay continued. Future systems approaches to decreasing in-hospital delay are warranted and would likely reduce infection while also reducing total hospital utilization.