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19 May 2017

New Research Confirms Link between High Temperatures and Surgical Site Infections

Temperature has a surprising impact on many areas of life which you may not expect it to. This makes sense when you think about it, given that temperature influences everything from cellular activity to states of matter. The influence of temperature on cellular activity is particularly pertinent here, as new research has shown an association between heightened temperatures and an increased likelihood of falling victim to a surgical site infection (SSI).

The research, published earlier this week in the journal of the Society for Healthcare Epidemiology of America, titled Infection Control & Hospital Epidemiology, demonstrated that such infections have a seasonal aspect. The study showed that temperatures above 90°F (32°C) were associated with a 28.9% increase in the likelihood of hospitalisation with a surgical site infection (SSI), as compared to temperatures less than 40°F (4°C).

Senior author of the study Philip M. Polgreen, who serves as Director of the Innovation Lab at The Signal Center for Health Innovation and Associate Professor of Internal Medicine and Epidemiology at the University of Iowa, said of the results, “We show that seasonality of surgical site infections is strongly associated with average monthly temperature. As temperatures rise, risk increases.

“However, the odds of any one person getting an infection are still small, and due to the limitations of our data, we still do not know which particular surgeries or patients are at more risk from higher temperature.”

In order to ascertain the true impact of temperature on surgical site infections, the researchers took data from the largest database of discharges from hospitals available in the US, known as the Nationwide Inpatient Sample, to identify each and every case in which an adult was hospitalised with a diagnosis of SSI between January 1998 and November 2011. They then used the longitude and latitude of each hospital to identify nearby weather stations. Monthly summary statistics including temperature, rainfall, and wind speed were then incorporated into the analysis. The study also included the analysis of certain subgroups based on the hospitals’ region, teaching status, and setting (urban or rural), as well as patient gender and age.

These combined parcels of data allowed the research team to assert that SSIs are in fact seasonal, with hospital discharges relating to SSIs rising by 26.5% in the peak month of August, as compared to the low point in January. The researchers further estimate that if the average number of at-risk surgeries performed during the months of July and August was reduced by 25%, this would result in around 1,700 less SSI diagnoses per year.

Seasonality and incidence were found to be similar across most of the aforementioned subgroups; however seasonality was greatest amongst patients in their 40s and 50s.

Christopher A. Anthony, first author of the study and surgery resident physician at the University of Iowa Roy J. and Lucille A. Carver College of Medicine, also commented on the research, “These results tell us that we need to identify the patients, surgeries, and geographic regions where weather-related variables are most likely to increase patients' risk for infections after surgery.

“This way, we can identify the patients at the greatest risk for surgical site infections during warmer summer months.”

Sam Bonson

Sam is an aspiring novelist with a passion for fantasy and crime thrillers. He is currently working as a content writer, journalist & editor in an attempt to expand his horizons.