Reducing Implant Infection in Orthopaedics (RIIiO): Results of a pilot study comparing the influence of forced air and resistive fabric warming technologies on postoperative infections following orthopaedic implant surgery

Analysis of the effects of intraoperative warming devices on surgical site infection in elective hip arthroplasty using a large nationwide database

INTRODUCTION

The aim of our study is to analyze the association of usage and type of warming device with the risk of surgical site infection (SSI) in patients who underwent hip arthroplasty, and to analyze the factors that increase the risk of SSI if the warming device is not used.

MATERIALS AND METHODS

This retrospective cross-sectional study identified subjects from data of "Evaluation of the Appropriate Use of Prophylactic Antibiotics". Included patients were defined as those who underwent elective unilateral hip hemiarthroplasty or total hip arthroplasty (THA). Patients were classified into no intraoperative warming device, forced air warming devices, and devices using conduction. Multiple logistic regression analysis was conducted to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) to assess the association between warming devices and SSI.

RESULTS

A total of 3945 patients met the inclusion criteria. Compared to those who received an intraoperative warming device, the odds of developing SSI were 1.9 times higher in those who did not receive intraoperative warming devices (aOR 1.9; 95% CI 1.1-3.6). The risk of SSI was 2.2 times higher with forced air warming devices compared to devices using conduction but this difference was not statistically significant (aOR 2.2; 95% CI 0.7-6.8). The risk of SSI increased in males (aOR 2.8; 95% CI 1.1-7.2), in patients under 70 years of age (aOR 4.4; 95% CI 1.6-10.4), in patients with a Charlson`s comorbidity index of 2 or higher (aOR 3.3; 95% CI 1.3-8.7), and in patients who underwent THA (aOR 3.8; 95% CI 1.7-8.3) when intraoperative warming devices were not used.

CONCLUSIONS

The use of intraoperative active warming devices is highly recommended to prevent SSI during elective hip arthroplasty. In particular, male patients younger than 70 years, those with a high CCI, and those undergoing THA are at significantly increased risk of SSI if intraoperative active warming devices are not used. Intraoperative warming device using conduction is likely superior to forced air warming device, but further studies are needed to confirm this.

Enhanced recovery after surgery (ERAS) protocols for total joint replacement surgery

The enhanced recovery after surgery (ERAS) protocols are a comprehensive therapeutic approach that prioritizes the well-being of patients. It encompasses several aspects such as providing sufficient nutritional support, effectively managing pain, ensuring appropriate fluid management and hydration, and promoting early mobilization after surgery. The advent of ERAS theory has led to a shift in focus within modern ERAS protocols. At present, ERAS protocols emphasize perioperative therapeutic strategies employed by surgeons and anesthesiologists, as well as place increased importance on preoperative patient education, interdisciplinary collaboration, and the enhancement of patient satisfaction and clinical outcomes. This editorial highlights the application of ERAS protocols in the current context of total joint replacement surgery.

Are Intra-operative Forced Air Warming Devices a Possible Source for Contamination During Hand Surgery?

Background Forced air warming (FAW) devices are routinely utilized in operating rooms for patient temperature control. However, there have been some controversy and conflicting evidence on whether they are a possible source of surgical site infections (SSIs) and contamination. Methods A total of 144 petri dishes were randomized to either a control or experimental group (72 in each group). Each trial consisted of six petri dishes in three locations (floor, table, and operative limb). Two dishes at each location were closed sequentially at one hour, two hours, and three hours. Two control and two experimental trials were performed in two separate operating suites with two different FAW devices. The petri dishes were then analyzed for growth for 48 hours. Two culture swabs from each FAW device hose were obtained and analyzed. Results None of the culture swabs analyzed showed any growth on blood or chocolate agar culture media. There was no significant difference in bacterial colony-forming units per cubic meter (CFU/m3) air between the trial and control groups in each location at one hour of exposure. At two hours of exposure, there was a significantly higher bacterial CFU/m3 air in the experimental group in the operative limb. At three hours of exposure, there was a significantly higher bacterial CFU/m3 air in the experimental group on the floor. However, overall, there was no difference in bacterial CFU/m3 air in both study groups at different times of exposure, incubation, or location. Conclusion Our study was unable to identify any statistically significant risk of contamination associated with the use of FAW devices. However, our study design was limited due to the absence of operating room staff during testing. For this reason, we recommend further research into this topic with the use of an active operating room, which includes simulated movement from the surgeon, anesthesia, scrub technician, nursing, and any other operating room staff who may be present during a real operation.

Key Elements of Enhanced Recovery after Total Joint Arthroplasty: A Reanalysis of the Enhanced Recovery after Surgery Guidelines

Recent guidelines have produced a consensus statement for perioperative care in hip and knee replacement. However, there is still a need for reanalysis of the evidence and recommendations. Therefore, we retrieved and reanalyzed the evidence of each recommended components of enhanced recovery after surgery (ERAS) based on the guidelines of total joint arthroplasty. For each one, we included for the highest levels of evidence and those systematic reviews and meta-analyses were preferred. The full texts were analyzed and the evidence of all components were summarized. We found that most of the recommended components of ERAS are supported by evidence, however, the implementation details of each recommended components need to be further optimized. Therefore, implementation of a full ERAS program may maximize the benefits of our clinical practice but this combined effect still needs to be further determined.

Resistant fabric warming is a viable alternative to forced-air warming to prevent inadvertent perioperative hypothermia during hemiarthroplasty in the elderly

BACKGROUND

Surgical site infection (SSI) is associated with inadvertent perioperative hypothermia (IPH). This can be prevented by active patient warming. However, results from comparisons of warming techniques are conflicting. They are based mostly on elective surgery, are from small numbers of patients, and are dominated by the market leader, forced-air warming (FAW). Furthermore, the definition of hypothermia is debatable and systematic reviews of warming systems conclude that a stricter control of temperature is required to study the benefits of warming.

AIM

To analyse core temperatures in detail in a large subset of elderly patients who took part in a randomized trial of patient warming following hemiarthroplasty who had received constant zero-flux thermometry to record their temperature.

METHODS

Regression models with a fixed effect for warming group and covariates related to temperature were compared for 257 participants randomized to FAW or resistant fabric warming (RFW) from a prior clinical trial.

FINDINGS

Those in the RFW group were -0.08°C cooler and had a cumulative hypothermia score -1.87 lower than those in the FAW group. There was no difference in the proportion of hypothermic patients at either <36.5°C or <36.0°C.

CONCLUSIONS

This is the first study to provide accurate temperature measurements in patients undergoing a procedure predominantly under regional rather than general anaesthetic. It shows that RFW is a viable alternative to FAW for preventing IPH during hemiarthroplasty. Further studies are needed to measure the benefits of patient warming in terms of clinically important outcomes.

Too Cool? Hip Fracture Care and Maintaining Body Temperature

Introduction:

Patients with hip fractures can become cold during the perioperative period despite measures applied to maintain warmth. Poor temperature control is linked with increasing complications and poorer functional outcomes. There is generic evidence for the benefits of maintaining normothermia, however this is sparse where specifically concerning hip fracture. We provide the first comprehensive review in this population.

Significance:

Large studies have revealed dramatic impact on wound infection, transfusion rates, increased morbidity and mortality. With very few studies relating to hip fracture patients, this review aimed to capture an overview of available literature regarding hypothermia and its impact on outcomes.

Results:

Increased mortality, readmission rates and surgical site infections are all associated with poor temperature control. This is more profound, and more common, in older frail patients. Increasing age and lower BMI were recognized as demographic factors that increase risk of hypothermia, which was routinely identified within modern day practice despite the use of active warming.

Conclusion:

There is a gap in research related to fragility fractures and how hypothermia impacts outcomes. Inadvertent intraoperative hypothermia still occurs routinely, even when active warming and cotton blankets are applied. No studies documented temperature readings postoperatively once patients had been returned to the ward. This is a point in the timeline where patients could be hypothermic. More studies need to be performed relating to this area of surgery.

Effects of a preoperative forced-air warming system for patients undergoing video-assisted thoracic surgery: A randomized controlled trial

BACKGROUND

The incidence of intraoperative hypothermia is still high despite the proposal of different preventive measures during thoracoscopic surgery. This randomized control study evaluated the effects of 30-minute prewarming combined with a forced-air warming system during surgery to prevent intraoperative hypothermia in patients undergoing video-assisted thoracic surgery under general anesthesia combined with erector spinae nerve block.

METHODS

Ninety-eight patients were randomly and equally allocated to prewarming or warming groups (n = 49 each). The primary outcome was the incidence of intraoperative hypothermia. Secondary outcomes were core temperature, irrigation and infused fluid, estimated blood loss, urine output, type of surgery, intraoperative anesthetic dosage, hemodynamics, recovery time, the incidence of postoperative shivering, thermal comfort, postoperative sufentanil consumption and pain intensity, patient satisfaction, and adverse events.

RESULTS

The incidence of intraoperative hypothermia was significantly lower in the prewarming group than the warming group (12.24% vs 32.65%, P = .015). Core temperature showed the highest decrease 30 minutes after surgery start in both groups; however, the rate was lower in the prewarming than in the warming group (0.31 ± 0.04°C vs 0.42 ± 0.06°C, P < .05). Compared with the warming group, higher core temperatures were recorded for patients in the prewarming group from T1 to T6 (P < .05). Significantly fewer patients with mild hypothermia were in the prewarming group (5 vs 13, P = .037) and recovery time was significantly reduced in the prewarming group (P < .05). Although the incidence of postoperative shivering was lower in the prewarming group, it was not statistically significant (6.12% vs 18.37%, P = .064). Likewise, the shivering severity was similar for both groups. Thermal comfort was significantly increased in the prewarming group, although patient satisfaction was comparable between the 2 groups (P > .05). No adverse events occurred associated with the forced-air warming system. Both groups shared similar baseline demographics, type of surgery, total irrigation fluid, total infused fluid, estimated blood loss, urine output, intraoperative anesthetic dosage, hemodynamics, duration of anesthesia and operation time, postoperative sufentanil consumption, and pain intensity.

CONCLUSION

In patients undergoing video-assisted thoracic surgery, prewarming for 30 minutes before the induction of anesthesia combined with a forced-air warming system may improve perioperative core temperature and the thermal comfort, although the incidence of postoperative shivering and severity did not improve.

Prevention of infection in primary THA and TKA

Rates of peri-prosthetic joint infection (PJI) in primary total hip and total knee arthroplasty range between 0.3% and 1.9%, and up to 10% in revision cases. Significant morbidity is associated with this devastating complication, the economic burden on our healthcare system is considerable, and the personal cost to the affected patient is immeasurable.

The risk of surgical site infection (SSI) and PJI is related to surgical factors and patient factors such as age, body mass index (BMI), co-morbidities, and lifestyle. Reducing the risk of SSI in primary hip and knee arthroplasty requires a multi-faceted strategy including pre-operative patient bacterial decolonization, screening and avoidance of anaemia, peri-operative patient warming, skin antisepsis, povidone-iodine wound lavage, and anti-bacterial coated sutures.

This article also considers newer concepts such as the influence of bearing surfaces on infection risk, as well as current controversies such as the potential effects of blood transfusion, laminar flow, and protective hoods and suits, on infection risk.

Cite this article: EFORT Open Rev 2020;5:604-613. DOI: 10.1302/2058-5241.5.200004