Normothermia in Arthroplasty

A Warm Air Blanket is Superior to a Heated Mattress in Preventing Perioperative Hypothermia in Orthopedic Arthroplasties, a Time-Series Analyses

BACKGROUND

Hypothermia is a common perioperative problem that can lead to severe complications. We evaluated whether a heated mattress (HM) is superior to a warm air blanket (WA) in preventing perioperative hypothermia in patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA).

METHODS

A retrospective cohort study was performed in a teaching hospital and data were collected for all patients undergoing THA or TKA between January 1, 2015 and May 1, 2022. We used logistic and linear regressions to analyze hypothermia occurrence and important complications. Results were adjusted for confounders and time, and was present in all subgroups and after imputation of missing data.

RESULTS

In total, 4,683 of 5,497 patients had information on type of heating. We found more perioperative hypothermia in patients treated with an HM compared to a WA for both THA (odds ratio-adjusted 1.42 [1.0 to 1.6] P = .06) and TKA (odds ratio-adjusted 2.10 [1.5 to 3.0] P < .01). There was no difference in postoperative infections between groups (all between 0.5% and 1.3%). Patients who had an HM significantly stayed longer in the postoperative ward (a mean difference of 4 [TKA] to 6 [THA] minutes, P < .01), but there was no difference in hospital stay.

CONCLUSION

A WA is superior compared to an HM in preventing perioperative hypothermia, with no increased risk of complications. Patients who have an HM stayed longer at the postoperative ward, potentially because of higher hypothermia rates. Therefore, it is suggested to use a WA instead of an HM.

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 Total Joint Arthroplasty (TJA): A Contemporary Systematic Review of Clinical Outcomes and Usage of Key Elements

BACKGROUND

Enhanced recovery after surgery (ERAS) is a pathway designed to improve the care of surgical patients and achieve early recovery. The clinical outcomes and usage of key elements of ERAS pathways in total joint arthroplasty (TJA) need further reanalysis. This article aims to provide an overview of the latest clinical outcomes and current usage of key elements of ERAS pathways in TJA.

METHODS

We undertook a systematic review of the PubMed, OVID, and EMBASE databases in February 2022. Studies investigating the clinical outcomes and usage of key elements of ERAS in TJA were included. The components of successful ERAS programs and their usage were further determined and discussed.

RESULTS

Twenty-four studies involving 216,708 patients assessed ERAS pathways for TJA. A total of 95.8% (23/24) of studies reported a reduced length of stay (LOS), followed by reduce overall opioid consumption or pain (87.5% [7/8]), save costs (85.7% [6/7]), improvements in patient-reported outcomes or functional recovery (60% [6/10]), and reduced incidence of complications (50% [5/10]). In addition, preoperative patient education (79.2% [19/24]), anesthetic protocol (54.2% [13/24]), use of local anesthetics for infiltration analgesia or nerve blocks (79.2% [19/24]), perioperative oral analgesia (66.7% [16/24]), perioperative surgical factors including reduced use of tourniquets and drains (41.7% [10/24]), use of tranexamic acid (41.7% [10/24]) and early mobilization (100% [24/24]) were contemporary comparatively "active" components of ERAS.

CONCLUSIONS

ERAS for TJA has favorable clinical outcomes in terms of reducing LOS and overall pain, saving costs, accelerating functional recovery, and reducing complications, although the evidence is still low in quality. In the current clinical scenario, only some "active" components of the ERAS program are widely used.

The Utility of Perioperative Products for the Prevention of Surgical Site Infections in Total Knee Arthroplasty and Lower Extremity Arthroplasty: A Systematic Review

Surgical site infections (SSIs) are among the most prevalent and devastating complications following lower extremity total joint arthroplasty (TJA). Strategies to reduce the rates can be divided into preoperative, perioperatives, and postoperative measures. A multicenter trial is underway to evaluate the efficacy of implementing a bundled care program for SSI prevention in lower extremity TJA including: (1) nasal decolonization; (2) surgical skin antisepsis; (3) antimicrobial incise draping; (4) temperature management; and (5) negative-pressure wound therapy for selected high-risk patients. The purposes of this systematic review were to provide a background and then to summarize the available evidence pertaining to each of these SSI-reduction strategies with special emphasis on total knee arthroplasty. A systematic review of the literature was conducted in accordance with the 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines. Five individual literature searches were performed to identify studies evaluating nasal decolonization temperature management, surgical skin antisepsis, antimicrobial incise draping, and negative-pressure wound therapy. The highest level of evidence reports was used in each product review, and if there were insufficient arthroplasty papers on the particular topic, then papers were further culled from the surgical specialties to form the basis for the review. There was sufficient literature to assess all of the various prophylactic and preventative techniques. All five products used in the bundled program were supported for use as prophylactic agents or for the direct reduction of SSIs in both level I and II studies. This systematic review showed that various pre-, intra-, and postoperative strategies are efficacious in decreasing the risks of SSIs following lower extremity TJA procedures. Thus, including them in the armamentarium for SSI-reduction strategies for hip and knee arthroplasty surgeons should decrease the incidence of infections. We expect that the combined use of these products in an upcoming study will support these findings and may further enhance the reduction of total knee arthroplasty SSIs in a synergistic manner.

Survival at 30 days in elderly patients with hip fracture surgery who were exposed to hypothermia: Survival study

The effect of hypothermia as a mortality risk factor at 30 days in the elderly who had hip fracture (HF) surgery is still controversial because it may be due to a set of poorly identified factors. In this study, we aim to determine if exposure to intra and immediate postoperative hypothermia increases the incidence of mortality at 30 days in elderly patients who had HF surgery.Survival study in the elderly who had HF surgery with and without exposure to hypothermia. Sociodemographic, anesthetic and surgical factors were collected. The temperature of the rectum was measured at the end of the surgery and in the recovery room. The effect of hypothermia was analyzed by the incidence of mortality at 30 days. Other results were considered, such as, surgical site infection (SSI), blood transfusions, and influence of implants used in the 30-day mortality.Three hundred eighty five subjects were eligible, to include 300. Inadvertent hypothermia was 12%, the 30-day overall mortality was 9% and in subjects with hypothermia it was 25% (P = .002). Subjects with hypothermia had a higher risk of SSI (relative risk 4.2, 95% confidence interval 1.3-13.6, P = .03) and receive more transfusions (relative risk 3.6, 95% confidence interval 2.0-6.5, P < .001).Elderly subjects with HF exposed to hypothermia who undergo hip hemiarthroplasty and who receive 2 or more blood transfusions during their treatment, are at greater risk of dying after 30 days of the surgery. Hypothermia, as a possible causative factor of mortality, should continue to be studied.

The Impact of Intraoperative Hypothermia on Blood Loss and Allogenic Blood Transfusion in Total Knee and Hip Arthroplasty: A Retrospective Study

Background

Total joint arthroplasty (TJA) usually leads to substantial blood loss, which may cause allogenic blood transfusion. Hypothermia occurring during operation has been reported to increase blood loss and transfusion rates in nonorthopedic cohorts. However, the relationship between intraoperative hypothermia and blood loss remains controversial in patients undergoing orthopedic surgeries. The aims of this study were to investigate the incidence of hypothermia and identify the impact of intraoperative body temperature and hypothermia on blood loss and transfusion rates in total knee and hip arthroplasty (TKA and THA, respectively).

Methods

This retrospective study enrolled 616 consecutive patients, who underwent primary unilateral TKA or THA at our institution during the period from April 2012 to July 2014. The occurrence of a temperature below 36°C during the operation was documented to identify the incidence of hypothermia. Univariate analysis was performed to find the risk factors for hypothermia. Multiple regression analysis and multivariate logistic regression analysis were employed to explore the association of intraoperative temperature and hypothermia with intraoperative blood loss and perioperative blood transfusion.

Results

The incidence of intraoperative hypothermia was 13.5%, 14.0%, and 13.1% in TJA, TKA, and THA, respectively. Intraoperative temperature (P = 0.045, P = 0.006) and hypothermia (P = 0.042, P < 0.001) were associated with intraoperative blood loss and perioperative transfusion in TKA. Intraoperative temperature (P = 0.002) was negatively related to the amount of blood loss, and hypothermia (P = 0.031) was the independent risk factor for transfusion in THA.

Conclusion

Intraoperative hypothermia is associated with increased blood loss and transfusion rates in TJA. Efforts should be made to maintain normothermia during operation in these patients.

Effect of forced-air warming blanket position in elective lumbar spine surgery: Intraoperative body temperature and postoperative complications

Background:

Perioperative hypothermia is linked to multiple postoperative complications including increased surgical bleeding, surgical site infection, myocardial events, and increased length of hospital stay. The purpose of this study is to determine the effects of forced-air warming blanket position, above the shoulders versus under the trunk/legs, on intraoperative core body temperature and perioperative complications in elective lumbar spine surgery.

Methods:

After IRB approval, patients were enrolled in a consecutive fashion and randomized to either upper body (Group I) or lower body (Group II) groups. Primary outcomes were intraoperative body temperature, incidence of hypothermia, postoperative complications, and infection. Secondary outcomes included blood loss, operative time, and length of stay.

Results:

Seventy-four patients were included (Group I, 38; Group II, 36, mean age 60.7 years, 54% of male). Average patient follow-up was 69 ± 33.6 days in Group I and 67 ± 34.6 days in Group II. Average intraoperative body temperature was 35.7 in Group I and 35.8 in Group II (P = 0.27). Incidence of critical hypothermia (T < 35°C) was 18.4% and 11.1% in Groups I and II, respectively (P = 0.52). Incidence of mild hypothermia (T: 35°C–36°C) was 34.2% and 30.56% in Groups I and II, respectively (P = 0.81). Separately, pooled analysis comparing average body temperature and incidence infection demonstrated a relationship between mild hypothermia and infection (P = 0.03).

Conclusion:

Compared to using a lower body Bair Hugger under the patient, using standard upper body Bair Hugger may be associated with increased surgical site infection. Given equivalent body warming, we recommend using the lower body Bair Hugger to avoid infection.

An evidence-based review of enhanced recovery after surgery in total knee replacement surgery

Rationale: Enhanced recovery after surgery is gaining popularity among orthopaedic surgeons across the globe and hence a strong evidence base had to be reviewed to make an evidence-based sustainable protocol.

Methods

The following databases, PubMed, OVID, Cochrane database and EMBASE were searched. The search was limited to 15 components of enhanced recovery after surgery programme which is divided into preoperative, intraoperative and postoperative phases. Inclusion criteria were restricted to articles published in English within the last 15 years and articles comprising of unicompartmental arthroplasty, revision knee arthroplasty, bilateral simultaneous knee arthroplasty and only hip arthroplasty excluded. The full texts were analysed and controversies and limitations of various studies were summarised.

Discussion

Each component of the programme was thoroughly reviewed and strength and weaknesses of the evidence base summarised. The strength of the evidence was assessed by critically appraising the study methodology and justifying the appropriateness of the inclusion in enhanced recovery after surgery protocol.

Conclusion

Enhanced recovery after surgery has already been used successfully in various surgical specialities. Enhanced recovery after surgery programmes in knee arthroplasty are yet to be established as a universal practice to be adopted globally. This evidence-based review provides an insight into the best evidence linked to each component and their rationale for inclusion in the proposed enhanced recovery after surgery protocol.

Thermoelectric Heat Patch for Clinical and Self-Management: Melanoma Excision Wound Care

Thermotherapy is considered to have potential beneficial effects when applied to wounds. Of particular relevance to this research are wounds that have dropped in temperature due to regional anaesthesia. This study is aimed at developing a normothermic system comprising of a heat patch controlled by external hardware. The study is divided into three parts: (i) the analyses of the skin temperature that form the foundation of the system; (ii) the development of an efficient wearable heat patch incorporating thermoelectric elements to electrical and thermal conductive textiles; and (iii) the hardware development to control the current flow to the thermoelectric elements thus managing the temperature of the heat patch and conserving current. It was observed that a distance of 3 cm between the thermoelectric elements provides ideal heat distribution relative to the surface area. The system allowed for an 80% reduction in current, while maintaining the temperature of the heat patch at the required thermophysiological skin temperature. Future studies will include development of a temperature sensor identifying the real-time temperature of the wound; and circuitry for switching the polarity of the thermoelectric elements. The cooling capabilities of the thermoelectric elements can be applied to wounds that have increased in temperature.

Reducing Implant Infection in Orthopaedics (RIIiO): a pilot study for a randomised controlled trial comparing the influence of forced air versus resistive fabric warming technologies on postoperative infection rates following orthopaedic implant surgery in adults

Background

Approximately 70,000 to 75,000 proximal femoral fracture repairs take place in the UK each year. Hemiarthroplasty is the preferred treatment for adults aged over 60 years. Postoperative infection affects up to 3% of patients and is the single most common reason for early return to theatre. Ultraclean ventilation was introduced to help mitigate the risk of infection, but it may also contribute to inadvertent perioperative hypothermia, which itself is a risk for postoperative infection. To counter this, active intraoperative warming is used for all procedures that take 30 min or more. Forced air warming (FAW) and resistive fabric warming (RFW) are the two principal techniques used for this purpose; they are equally effective in prevention of inadvertent perioperative hypothermia, but it is not known which is associated with the lowest infection rates. Deep surgical site infection doubles operative costs, triples investigation costs and quadruples ward costs. The Reducing Implant Infection in Orthopaedics (RIIiO) study seeks to compare infection rates with FAW versus RFW after hemiarthroplasty for hip fracture. A cost-neutral intervention capable of reducing postoperative infection rates would likely lead to a change in practice, yield significant savings for the health economy, reduce overall exposure to antibiotics and improve outcomes following hip fracture in the elderly. The findings may be transferable to other orthopaedic implant procedures and to non-orthopaedic surgical specialties.

Methods

RIIiO is a parallel group, open label study randomising hip fracture patients over 60 years of age who are undergoing hemiarthroplasty to RFW or FAW. Participants are followed up for 3 months. Definitive deep surgical site infection within 90 days of surgery, the primary endpoint, is determined by a blinded endpoint committee.

Discussion

Hemiarthroplasty carries a risk of deep surgical site infection of approximately 3%. In order to provide 90% power to demonstrate an absolute risk reduction of 1%, using a 5% significance level, a full trial would need to recruit approximately 8630 participants. A pilot study is being conducted in the first instance to demonstrate that recruitment and data management strategies are appropriate and robust before embarking on a large multi-centre trial.

Trial registration

ISRCTN, ISRCTN74612906. Registered on 27 February 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3011-y) contains supplementary material, which is available to authorized users.

What is the incidence of inadvertent hypothermia in elderly hip fracture patients and is this associated with increased readmissions and mortality?

Background

Globally the incidence of fragility hip fractures is rising with increasingly elderly and co-morbid patients. These injuries are associated with a high morbidity and mortality.

Aims

This clinical study's primary outcome is to establish the rate of operative inadvertent hypothermia (<36 °C) in elderly hip fracture patients (>65 years old). We also aimed to identify risk factors and outcomes in patients with inadvertent hypothermia.

Patients and Methods

A single centre, retrospective study of 929 hip fracture patients managed operatively between June 2015 and July 2017 was conducted. Patients' demographic, anaesthetic and surgical variables were analysed together with outcomes for length of stay (LoS), 30-day re-admissions, and 30-day mortality.

Results

Overall rates of inadvertent hypothermia in elderly hip fracture patients undergoing surgery were 10%, with increasing age (p = 0.006) and pre-operative hypothermia (p < 0.0001) as risk factors. Patient's hypothermic pre-operatively compared with normothermic patients were 1.9 times more likely to be <36 °C on leaving theatre. There was a trend towards a higher 30-day mortality (χ²(1) = 2.818, p = 0.093), and a significantly higher mortality in patients undergoing SHS (p = 0.03). No survival differences for LoS were observed between hypothermic and ≥36 °C patients (χ2(1) = 0.069, p = 0.79). 30-day re-admissions were higher in hypothermic patients (χ2(1) = 16.301, p < 0.0001).

Conclusion

Rates of inadvertent hypothermia are high in operatively managed hip fracture patients and are significantly associated with a higher 30-day readmission rate with a trend towards higher 30-day mortality.