Biofilm on total joint replacement materials can be reduced through electromagnetic induction heating using a portable device.

BACKGROUND: Periprosthetic joint infection is a serious complication following joint replacement. The development of bacterial biofilms bestows antibiotic resistance and restricts treatment via implant retention surgery. Electromagnetic induction heating is a novel technique for antibacterial treatment of metallic surfaces that has demonstrated in-vitro efficacy. Previous studies have always employed stationary, non-portable devices. This study aims to assess the in-vitro efficacy of induction-heating disinfection of metallic surfaces using a new Portable Disinfection System based on Induction Heating. METHODS: Mature biofilms of three bacterial species: S. epidermidis ATCC 35,984, S. aureus ATCC 25,923, E. coli ATCC 25,922, were grown on 18 × 2 mm cylindrical coupons of Titanium-Aluminium-Vanadium (Ti6Al4V) or Cobalt-chromium-molybdenum (CoCrMo) alloys. Study intervention was induction-heating of the coupon surface up to 70ºC for 210s, performed using the Portable Disinfection System (PDSIH). Temperature was monitored using thermographic imaging. For each bacterial strain and each metallic alloy, experiments and controls were conducted in triplicate. Bacterial load was quantified through scraping and drop plate techniques. Data were evaluated using non-parametric Mann-Whitney U test for 2 group comparison. Statistical significance was fixed at p ≤ 0.05. RESULTS: All bacterial strains showed a statistically significant reduction of CFU per surface area in both materials. Bacterial load reduction amounted to 0.507 and 0.602 Log10 CFU/mL for S. aureus on Ti6Al4V and CoCrMo respectively, 5.937 and 3.500 Log10 CFU/mL for E. coli, and 1.222 and 0.372 Log10 CFU/mL for S. epidermidis. CONCLUSIONS: Electromagnetic induction heating using PDSIH is efficacious to reduce mature biofilms of S aureus, E coli and S epidermidis growing on metallic surfaces of Ti6Al4V and CoCrMo alloys.

Impact of parylene coating on heating performance of intravenous fluid warmer: a bench study.

BACKGROUND: Perioperative hypothermia is a common occurrence, particularly with the elderly and pediatric age groups. Hypothermia is associated with an increased risk of perioperative complications. One method of preventing hypothermia is warming the infused fluids given during surgery. The enFlow™ intravenous fluid warmer has recently been reintroduced with a parylene coating on its heating blocks. In this paper, we evaluated the impact of the parylene coating on the new enFlow's fluid warming capacity. METHODS: Six coated and six uncoated enFlow cartridges were used. A solution of 10% propylene glycol and 90% distilled H2O was infused into each heating cartridge at flow rates of 2, 10, 50, 150, and 200 ml/min. The infused fluid temperature was set at 4 °C, 20 °C, and 37 °C. Output temperature was recorded at each level. Data for analysis was derived from 18 runs at each flow rate (six cartridges at three temperatures). RESULTS: The parylene coated fluid warming cartridge delivered very stable output of 40 °C temperatures at flow rates of 2, 10, and 50 ml/min regardless of the temperature of the infusate. At higher flow rates, the cartridges were not able to achieve the target temperature with the colder fluid. Both cartridges performed with similar efficacy across all flow rates at all temperatures. CONCLUSIONS: At low flow rates, the parylene coated enFlow cartridges was comparable to the original uncoated cartridges. At higher flow rates, the coated and uncoated cartridges were not able to achieve the target temperature. The parylene coating on the aluminum heating blocks of the new enFlow intravenous fluid warmer does not negatively affect its performance compared to the uncoated model.

Characterization, Antioxidant and Antibacterial Potentials of Tamarindus indica L. Fruit Pulp Extract Loaded O/W Nanoemulsions

Abstract The main purposes of the current study were to formulate o/w nanoemulsions as a carrier for Tamarindus indica (tamarind) fruit pulp extract and to study the antioxidant and antibacterial potentials of nanoemulsions containing tamarind extract, focusing on cosmetic/hygiene applications. The o/w nanoemulsions using a mixture of Tween 80 and Span 80 as an emulsifier (5%w/w) were prepared by a high pressure homogenization process. Two concentrations of sweet tamarind extract, 3.3 and 6.6%w/w, based on the bioactivity study, were incorporated into the blank nanoemulsions to produce loaded nanoemulsions, F1-3.3TE (3.3%) and F1- 6.6TE (6.6%). As compared with the unloaded nanoemulsion, both tamarind extract loaded nanoemulsions showed reduced pH and significantly increased viscosity. Overall, the loaded nanoemulsions had droplet sizes of approximately 130 nm, zeta potential around -38 mV and polydispersity index (PDI) values less than 0.2. The nanoemulsion F1-3.3TE had better stability (e.g. significantly greater % tartaric acid content and lesser PDI value) than the nanoemulsion F1-6.6TE did. The antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl assay revealed that the nanoemulsions F1-3.3TE and F1-6.6TE had scavenging activities of 81.66 ± 0.77% and 63.80 ± 0.79%, respectively. However, antioxidant activity of these two formulations decreased under stress conditions (heating-cooling cycles). Such incidence did not occur for their antibacterial properties investigated by agar well diffusion technique. The two formulations exhibited inhibition zones of approximately 24.0-27.7 mm against Staphylococcus aureus and Staphylococcus epidermidis, responsible for malodor of underarms. The results suggest the potential of using sweet tamarind pulp extract loaded nanoemulsions as hygiene products.

Effects of different thermal insulation methods on the nasopharyngeal temperature in patients undergoing laparoscopic hysterectomy: a prospective randomized controlled trial.

BACKGROUND: This study explored the comparison of the thermal insulation effect of incubator to infusion thermometer in laparoscopic hysterectomy. METHODS: We assigned 75 patients enrolled in the study randomly to three groups: Group A: Used warming blanket; group B: Used warming blanket and infusion thermometer; group C: Used warming blanket and incubator. The nasopharyngeal temperature at different time points during the operation served as the primary outcome. RESULTS: The nasopharyngeal temperature of the infusion heating group was significantly higher than that of the incubator group 60 min from the beginning of surgery (T3): 36.10 ± 0.20 vs 35.81 ± 0.20 (P<0.001)90 min from the beginning of surgery (T4): 36.35 ± 0.20 vs 35.85 ± 0.17 (P<0.001). Besides, the nasopharyngeal temperature of the incubator group was significantly higher compared to that of the control group 60 min from the beginning of surgery (T3): 35.81 ± 0.20 vs 35.62 ± 0.18 (P<0.001); 90 min from the beginning of surgery (T4): 35.85 ± 0.17 vs 35.60 ± 0.17 (P<0.001). Regarding the wake-up time, that of the control group was significantly higher compared to the infusion heating group: 24 ± 4 vs 21 ± 4 (P = 0.004) and the incubator group: 24 ± 4 vs 22 ± 4 (P = 0.035). CONCLUSION: Warming blanket (38 °C) combined infusion thermometer (37 °C) provides better perioperative thermal insulation. Hospitals without an infusion thermometer can opt for an incubator as a substitute. TRIAL REGISTRATION: This trial was registered with ChiCTR2000039162 , 20 October 2020.

Failure to eradicate non-tuberculous mycobacteria upon disinfection of heater-cooler units: results of a microbiological investigation in northwestern Italy.

BACKGROUND: Heater-cooler units (HCUs) used during cardiopulmonary bypass may become colonized with non-tuberculous mycobacteria (NTM), including Mycobacterium chimaera. Recently, a worldwide investigation conducted in hospitalized infected patients has detected M. chimaera in several Stockert 3T HCUs manufactured by LivaNova. AIM: Microbiological surveillance on Stockert 3T (LivaNova) and Maquet HCU40 (Getinge) devices as well as an evaluation of the efficacy of their recommended decontamination protocols. METHODS: A total of 308 water samples were collected from 29 HCUs: 264 samples were collected from 17 Stockert 3T HCUs and 44 samples from 12 Maquet HCU40 devices. Samples were tested for total viable counts (TVCs) at both 22 and 36°C, Pseudomonas aeruginosa, coliform bacteria, and NTM. The microbiological surveillance began in June 2017 and ran until October 2019. FINDINGS: A total of 308 HCU water samples were analysed, 65.5% of which yielded NTM. The most frequently colonized device with NTM was the Stockert 3T (88.2%), with a frequency of positive samples of 59.5% (157/264). The Maquet HCU40 devices less frequently yielded NTM (33.3%), with a frequency of positive water samples of 13.6% (6/44). Disinfection procedures were effective in reducing TVCs of bacteria with the exception of NTM species. NTM were detected in both pre-disinfection (50.1%) and post-disinfection (55.7%) samples, and no significant association was found between disinfection and NTM results both in Stockert 3T and Maquet HCU40 devices. CONCLUSION: This study suggests that manufacturers' procedures for disinfection are ineffective and/or inadequate. Until effective disinfection protocols become available, the only way to minimize the risk of NTM contamination is to closely monitor the water quality in the HCU, keep it as clean as possible, and treat it like any other biohazardous material.

The effect of sodium thiosulfate on the recovery of Mycobacterium chimaera from heater-cooler unit water samples.

BACKGROUND: Heater-cooler units (HCUs) have been implicated in the recent global outbreak of invasive Mycobacterium chimaera infection among patients following cardiothoracic surgery. Because infected patients tend to remain asymptomatic for extended periods, detection of M. chimaera from HCUs in real time is essential to halting the ongoing M. chimaera HCU-associated outbreak. Sample collection protocols to evaluate the presence of M. chimaera offer conflicting recommendations regarding the addition of sodium thiosulfate (NaT) during the collection process. AIM: To study the effect of NaT on M. chimaera recovery and culture contamination. METHODS: Seventy-six paired HCU water samples (with and without NaT) were collected, processed and cultured simultaneously into Lowenstein-Jensen slants, Middlebrook 7H10 agar plates, and mycobacterial growth indicator tubes (MGITs), and incubated at 37°C. A subset of 31 paired samples was additionally cultured on MGITs and incubated at 30°C. FINDINGS: Of 76 samples incubated at 37°C in each of the three media, with and without NaT, M. chimaera was identified in at least one aliquot of 21 samples. CONCLUSION: The presence of NaT did not significantly increase the probability of recovering M. chimaera in a multi-variable conditional logistic model and culture contamination rates were similar between aliquots with and without NaT. In the subset of samples cultured on MGITs at both 30°C and 37°C, the presence of NaT again was not associated with M. chimaera recovery, but was significantly associated with reduced culture contamination.

Prevention of Perioperative Hypothermia: A Prospective, Randomized, Controlled Trial of Bair Hugger Versus Inditherm in Patients Undergoing Elective Arthroscopic Shoulder Surgery.

PURPOSE: To determine if a clinically significant difference in the core body temperature (CBT) exists between the Bair Hugger (BH) and Inditherm (IT) warming devices in patients undergoing arthroscopic shoulder surgery. METHODS: This was a parallel, 2-treatment, prospective, randomized, controlled trial conducted in patients undergoing elective arthroscopic shoulder surgery in the beach-chair position using room-temperature irrigation fluid. The BH was used as the indicative forced-air warming device, whereas the IT served as the indicative resistive heating system. By use of a minimal clinically significant difference of 0.6°C and standard deviation of 0.6°C, a power analysis showed that a sample size of 90 patients (45 per group) would be required. Patients fulfilling the inclusion criteria were recruited from the clinics of the senior authors. Anesthetic and surgical protocols were standardized. The intraoperative CBT was recorded every 5 minutes using a nasopharyngeal thermistor probe. Demographic data as well as the volume of irrigation fluid used were also noted. RESULTS: A steady decline in the CBT was observed in both groups up to 30 minutes after induction of anesthesia. Beyond 30 minutes, the BH group showed a gradual increase in temperature whereas it continued to decline in the IT group. A statistically significant difference in the CBT was observed from 60 minutes onward (P = .025). This difference continued to increase up to 90 minutes (P < .001). At no time was a rise in the CBT observed in the IT group. At completion of the study and surgical procedure, 13 of 47 patients in the BH group and 32 of 44 patients in the IT group had hypothermia (P = .0002). CONCLUSIONS: The CBT was statistically significantly better with the use of the BH compared with the IT mattress. However, the differences in the CBT did not reach the level of clinical significance of 0.6°C. Far fewer patients in the BH group had hypothermia at the end of surgery. Therefore, this study supports the use of the BH in elective arthroscopic shoulder surgery for the prevention of hypothermia. LEVEL OF EVIDENCE: Level I.

Thermal burns of the spectacle associated with supplementary heating in native New Zealand geckos.

Case history: Gradual onset of ocular opacity was observed in three gold-striped geckos (Woodworthia chrysosiretica), and five Pacific geckos (Dactylocnemis pacificus) held in two adjacent terrariums in a zoological institution located in the North Island of New Zealand. Ultraviolet light and heat had been provided for the previous 3-4 years by a fluorescent bulb, but in the last 4 weeks of winter a ceramic heat bulb had been added, situated 10 cm above the upper mesh of the cageClinical findings: All eight geckos presented with mostly bilateral lesions of varying severity confined to the central or upper quadrant of the spectacles. These lesions ranged from variable areas of opacity within the stroma of the spectacle to similarly distributed ulcers of the surface epithelium of both spectacles. The spectacle lesions in the Pacific geckos responded well to treatment with topical combined antimicrobial therapy, within 18-29 days. The gold-striped geckos suffered complications including dysecdysis, severe spectacle ulceration and perforation, mycotic spectaculitis, and widespread mycotic dermatitis resulting in death or leading to euthanasia.Pathological findings: In the three gold-striped geckos, there were extensive areas of deep ulceration and replacement of the spectacle with a thick serocellular crust containing large numbers of fungal elements. The affected areas of the stroma were expanded by large deposits of proteinaceous and mucinous material, pyknotic cellular debris and moderate numbers of heterophils and macrophages as well as infiltrating fungal hyphae.Diagnosis: Mycotic spectaculitis with ulceration and perforation, and disseminated mycotic dermatitis likely secondary to thermal burns.Clinical relevance: This is the first report of thermal burns of the spectacle in any reptile. There was species variation in the burn severity with gold-striped geckos showing more severe lesions, possibly due to a mix of behavioural and anatomical factors. The thermal burns to the spectacles in three cases were complicated by delayed healing, perforation, dysecdysis and severe mycotic infection.

New Concept Air Conditioning System for the Operating Room to Minimize Patient Cooling and Surgeon Heating: A Historical Control Cohort Study.

BACKGROUND: Intraoperative hypothermia is a common adverse event. For avoiding the complication due to hypothermia, many warming devices and methods have been used in perioperative period. It has been reported that more patients undergoing laparoscopic surgery tend to have hypothermia than with open surgery. To avoid intraoperative hypothermia, many kinds of warming tools have been used. But, it was also reported that some warming methods increased perceptions of distraction and physical demand. METHODS: To achieve both patients' normothermia and surgeons' comfort, new air conditioning (AC) system was designed with considering the characteristics of laparoscopic surgery. The temperature of the airflows to the patient and to the surgeons can be adjusted independently in this new system. The new system has two parts. One controls the temperature of the central area over the operation table. The air from this part falls on the patients. The other part is the lateral area beside the operating table; the air from this part falls on the surgeons. The subjects of this study were 160 gastric cancer patients and 316 colorectal cancer patients undergoing laparoscopic surgery. The temperature of the central flow was set 23.5 °C, and the temperature of the lateral flow was set 22 °C just after the anesthesia. The number of timepoints the patient spent in hypothermic state, defined as a temperature cooler by 0.5 °C or more than that at the starting point of surgery, was determined in each patient. RESULTS: In the results, the rate of hypothermic state in old operation rooms was 23.8% and that in new operation rooms was 2.7% in male gastric cancer patients (p < 0.01). And those were 37.1% in old operation rooms and 0.9% in new operation rooms in female gastric cancer patients (p < 0.01). The rate of hypothermic state in old operation rooms was 30.0% and that in new operation rooms was 9.5% in male colorectal cancer patients (p < 0.01). And those were 41.6% in old operation rooms and 8.9% in new operation rooms in female colorectal cancer patients (p < 0.01). The similar results were showed in the study, which subjects were limited the patients undergoing surgery in 2015 and 2016; which were the last year the old operation rooms were used and the first year the new operation rooms were used. CONCLUSIONS: Thus, the usefulness of the new air conditioning system for achieving both patients' normothermia and comfort of surgeons could be verified in this study.

Comparing Forced-Air to Resistive-Polymer Warming for Perioperative Temperature Management: A Retrospective Study.

PURPOSE: Compare perioperative temperature management between forced-air warming (FAW) and resistive-polymer heating blankets (RHBs). DESIGN: A retrospective, quasi-experimental study. METHODS: Retrospective data analysis of nonspine orthopedic cases (N = 426) over a one-year period including FAW (n = 119) and RHBs (n = 307). FINDINGS: FAW was associated with a significantly higher final intraoperative temperature (P = .001, d = 0.46) than the RHB. The incidence of hypothermia was not found to be significantly different at the end (P = .102) or anytime throughout surgery (P = .270). Of all patients who started hypothermic, the FAW group had a lower incidence of hypothermia at the end of surgery (P = .023). CONCLUSIONS: FAW was associated with higher final temperatures and a greater number of normothermic patients than RHBs. However, no causal relationship between a warming device and hypothermia incidence should be assumed.

E-Cigarettes and Cancer Risk.

From the time of their introduction, the popularity of e-cigarettes (electronic nicotine-delivery systems) has been rising. This trend may reflect the general belief that e-cigarettes are a less hazardous alternative to combustible cigarettes. However, the potential cancer-related effects of increased activation of the sympathoadrenal system induced by the inhalation of nicotine, the primary component of the e-cigarettes, are completely overlooked. Therefore, the aim of this review is to describe mechanisms that may connect the use of e-cigarettes and an increased risk for cancer development, as well as their stimulatory effect on cancer progression. Available preclinical data indicate that activation of the sympathetic nervous system by nicotine inhaled from e-cigarettes may stimulate cancer development and growth by several mechanisms. This issue might be especially important for oncological patients as they may have the misconception that compared with combustible cigarettes, e-cigarettes represent a risk-free alternative.

Comparison of portable blood-warming devices under simulated pre-hospital conditions: a randomised in-vitro blood circuit study.

Pre-hospital transfusion of blood products is a vital component of many advanced pre-hospital systems. Portable fluid warmers may be utilised to help prevent hypothermia, but the limits defined by manufacturers often do not reflect their clinical use. The primary aim of this randomised in-vitro study was to assess the warming performance of four portable blood warming devices (Thermal Angel, Hypotherm X LG, °M Warmer, Buddy Lite) against control at different clinically-relevant flow rates. The secondary aim was to assess haemolysis rates between devices at different flow rates. We assessed each of the four devices and the control, at flow rates of 50 ml.min-1 , 100 ml.min-1 and 200 ml.min-1 , using a controlled perfusion circuit with multisite temperature monitoring. Free haemoglobin concentration, a marker of haemolysis, was measured at multiple points during each initial study run with spectrophotometry. At all flow rates, the four devices provided superior warming performance compared with the control (p < 0.001). Only the °M Warmer provided a substantial change in temperature at all flow rates (mean (95%CI) temperature change of 21.1 (19.8-22.4) °C, 20.4 (19.1-21.8) °C and 19.4 (17.7-21.1) °C at 50 ml.min-1 , 100 ml.min-1 and 200 ml.min-1 , respectively). There was no association between warming and haemolysis with any device (p = 0.949) or flow rate (p = 0.169). Practical issues, which may be relevant to clinical use, also emerged during testing. Our results suggest that there were significant differences in the performance of portable blood warming devices used at flow rates encountered in clinical practice.

The effectiveness of air-free warming systems on perioperative hypothermia in total hip and knee arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Perioperative hypothermia is a common and serious complication during surgery. Different warming systems are used to prevent perioperative hypothermia. However, there have been no previous meta-analyses of the effectiveness of air-free warming systems on perioperative hypothermia in patients undergoing joint arthroplasty. METHODS: We systematically searched PubMed, EMBASE, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases to collect randomized controlled trials (RCTs) from inception to August 2018. These RCTs compared the effects of air-free warming with forced-air (FA) warming system in patients undergoing joint arthroplasty. Postoperative temperature, core temperature during surgery, thermal comfort, blood loss and incidence of shivering and hypothermia were analyzed. RESULTS: A total of 287 patients from 6 clinical studies were included in the analysis. In summary, there was no significant difference in the postoperative temperature (WMD -0.043, 95% CI -0.32 to 0.23, P = .758) between the air-free warming and FA warming groups. No statistical difference (WMD 0.058, 95% CI -0.10 to 0.22, P = .475) was found in core temperatures at 0 minutes during surgery between the air-free warming and FA warming groups. Furthermore, there was no statistical difference in thermal comfort, blood loss or incidence of shivering and hypothermia between the air-free warming and FA warming groups. CONCLUSIONS: Air-free warming system was as effective as FA warming system in patients undergoing joint arthroplasty.

Normothermia is Best Achieved by Warming Above and Below with Pre-warming Adjunct: A Comparison of Conductive Fabric Versus Forced-air and Water.

BACKGROUND: Although forced-air warming is the most commonly used method for perioperative patient warming, it is fundamentally problematic because it disturbs the carefully designed airflow in the operating room. Because unintended hypothermia has significant consequences, there is a need for more effective warming strategies. The effectiveness of warming technologies that apply heat through the skin is based on surface-area contact with the heat source and the duration of pre-warming. Therefore, we sought to test the therapeutic effectiveness of combined above- and below-warming therapies. Our hospital prohibits forced-air warming before the patient is draped, so a secondary goal was to determine the effect of preoperative warming using a system that does not interfere with airflow in the operating room. METHODS: We prospectively randomized 35 patients undergoing total knee arthroplasty into two groups: 1) forced-air warming/water mattress, using both WarmTouch® upper-body forced-air warming (Medtronic/Covidien Inc., Dublin, Ireland) and a Norm-O-Temp® underbody water mattress (CSZ/Gentherm Inc., Cincinnati, OH, USA), and 2) conductive fabric warming, using a HotDog® electric upper-body blanket (Augustine Temperature Management LLC, Eden Prairie, MN, USA) and a HotDog® underbody mattress. RESULTS: Throughout the surgical procedure, group 2 patients had significantly higher temperatures; this group experienced superior pre-warming during preoperative preparations and thus the redistribution temperature drop following the induction of anesthesia was reduced. Both groups achieved 100% normothermia by the end of surgery. CONCLUSION: Based solely on the temperatures at the end of surgery, these data indicate that forced-air warming in conjunction with a water mattress warming system is as effective as a conductive fabric electric warming system alone.

Characterisation of aluminium release by the enFlow® fluid-warming system in crystalloids and blood products.

The use of uncoated aluminium-heated plates in an intravenous fluid-warming system has been shown to produce high levels of aluminium in Sterofundin 1/1E, a balanced crystalloid solution. However, the effect of this fluid-warming device on other balanced crystalloid solutions and blood products has not been studied. Using mass spectrometry we measured aluminium levels in Plasma-Lyte 148, compound sodium lactate solution, 4% human albumin solution, expired resuspended packed red cells and fresh frozen plasma that were pumped through an enFlow® fluid-warming system at 2 ml.min-1 . Samples were taken at baseline before heating and then at 10-min intervals up to 60 min with the system set to warm the fluids to 40 °C. High concentrations of aluminium were found for Plasma-Lyte 148 and compound sodium lactate solutions (mean (SD) 223 (0.6) µmol.l-1 and 163 (0.2) µmol.l-1 at 60 min, respectively); both concentrations were significantly greater than the United States Food and Drug Administration recommended maximum limit for aluminium in intravenous nutrition of 25 µg.l-1 (0.9 µmol.l-1 ). Lower aluminium levels were found in 4% human albumin solutions, expired resuspended red cells and fresh frozen plasma at 60 min (mean (SD) 5.7 (0.1) µmol.l-1 , 2.7 (0.0) µmol.l-1 and 2.3 (0.4) µmol.l-1 , respectively). The process allowing addition of aluminium to be added to Sterofundin 1/1E by the enFlow fluid warmer also occurs in Plasma-Lyte 148 and compound sodium lactate solutions and to a lesser degree in blood products. The exact mechanism facilitating this process and its clinical significance remain unclear.

Postoperative Myocardial Injury in Middle-Aged and Elderly Patients Following Curative Resection of Esophageal Cancer With Aggressive or Standard Body Temperature Management: A Randomized Controlled Trial.

BACKGROUND: Risk of intraoperative hypothermia is relatively high in middle-aged and elderly patients undergoing curative resection of esophageal cancer, which may cause myocardial ischemia during the early postoperative period. The objective of this study was to compare aggressive or standard body temperature management for lowering the incidence of postoperative myocardial injury that was assessed by troponin levels collected at a priori defined set times in these patients. METHODS: Seventy patients undergoing elective curative resection of esophageal cancer were randomly assigned to undergo aggressive body temperature management (nasopharyngeal temperature ≥36°C) or standard body temperature management (n = 35 in each arm). The primary outcome was myocardial injury, defined as the occurrence of elevated troponin I (>0.06 µg/L) or elevated high-sensitivity troponin T (≥0.065, or 0.02 µg/L≤ high-sensitivity troponin T <0.065 µg/L, but with an absolute change of at least 0.005 µg/L) or both during 2 days after surgery. Secondary outcomes included (1) severe arrhythmia, including atrial fibrillation, supraventricular tachycardia, frequent premature ventricular contractions intraoperatively or during 3 days postoperatively; (2) hypoxemia or metabolic acidosis during the first 12 h postoperatively; and (3) deep vein thrombosis or pulmonary embolism during 3 days postoperatively. RESULTS: Incidence of postoperative 2-day myocardial injury was 8.6% (3/35) among patients receiving aggressive body temperature management and 31.4% (11/35) among patients receiving standard body temperature management (P = .017, χ). Relative risk of myocardial injury in the aggressive body temperature management group was 0.27 (95% CI, 0.08-0.89). Incidence of intra- and postoperative 3-day severe cardiac arrhythmia was 2.9% (1/35) among patients receiving aggressive body temperature management and 28.6% (10/35) among patients receiving standard body temperature management. Incidence of postoperative 12-h hypoxia was 17.1% (6/35) with aggressive body temperature management and 40.0% (14/35) with standard body temperature management. Incidence of postoperative 12-h metabolic acidosis was 20% (7/35) among patients receiving aggressive body temperature management and 48.6% (17/35) among patients receiving standard body temperature management. Incidence of postoperative 3-day deep vein thrombosis or pulmonary embolism was 0% (0/35) with aggressive body temperature management and 2.9% (1/35) with standard body temperature management. CONCLUSIONS: Aggressive body temperature management may be associated with a lower incidence of postoperative myocardial injury.

Investigation and Evaluation of Potential Aerosol Release by Maquet/Getinge Heater-Cooler Units Used during Cardiac Surgery.

BACKGROUND: Heater-Cooler units (HCUs) supply tempered water through blood heat exchangers and through warming/cooling blankets to control the body temperature of heart surgery patients. Bacteria which potentially colonize the stored water may escape from the tank into the environment and are carried by the device's cooling air exhaust into the sterile field and finally may infect open chest heart surgery patients. Reports from several countries are connecting the infection of open chest heart surgery patients to airborne transmitted Mycobacteria chimaera which were found in the water of heater-cooler devices. As a consequence of the vigilance system for medical products, we investigated the potential release and the possible transmission of bacteria from the tank water into the sterile operating field. MATERIALS AND METHODS: In the absence of an evaluation standard for this problem, measurable acceptance criteria for particle releases and a qualitative method for bacteria transmission assessment have been deployed. To assess potential bacteria transmission into the sterile field, tank water of the test devices was inoculated with high concentrations of Pseudomonas aeruginosa (reference strain ATCC15442) and operated in an operating room with simulated use. RESULTS: The particle release at the tank lids of the Maquet/Getinge HCU 30 and HCU 40 during the filling of the tubes with water (deaeration) and during the removal of water from the tubes (emptying) increased slightly, but close to the blank readings for the larger particles. As expected, the particle release at the cooling air grids was higher than around the tank openings. Consistent with the particle measurements, no bacteria from the tank water were found in the sterile field during simulated use of all highly inoculated machines in an operating room. CONCLUSION: In summary, we assess the risk of infecting open chest heart surgery patients with aerosol-transmitted bacteria from water inside the Maquet/Getinge HCU 40, HCU 30 to be negligible, if handled in accordance with common clinical hygienic precautions.

Mycobacterium chimaera in heater-cooler units: new technical approach for treatment, cleaning and disinfection protocol.

Mycobacterium chimaera infections have mainly been associated with the heater-cooler unit (HCU) and, ultimately, linked to contaminated aerosols in the operation room. The contamination status of HCUs seems to be influenced by the maintenance, therefore, according to the manufacturer's recommendations, peracetic acid (Puristeril) was introduced to increase HCU cleaning and disinfection protocol maintenance. Aerosol dispersion from Puristeril during maintenance can cause adverse effects to nearby workers. We aim to describe our technique to reduce the impact of Puristeril on operating room staff and to limit dispersion of its aerosol in the environment by performing the cleaning procedure through a closed circuit.

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.