An Open label, Randomised Controlled trial on the effectiveness of the Orve+ Wrap® versus Forced Air Warming in restoring normothermia in the Post Anaesthetic Care Unit

AIMS AND OBJECTIVES: This study aims to determine the clinical effectiveness and safety of the Orve+Wrap® thermal blanket. BACKGROUND: Inadvertent peri-operative hypothermia is a common problem in Post Anaesthetic Care Units and can have significant effects on patients' post-operative morbidity. Despite its commercial availability there is no clinical evidence on the effectiveness of Orve+Wrap®. DESIGN: A single centre prospective, open label, non-inferiority randomized controlled trial. METHODS: Post-operative hypothermic (35.0°C - 35.9°C) patients who had undergone elective surgery were randomised to receive either Orve+Wrap® or Forced Air Warming for the during their PACU stay. Patient temperatures we recorded every 10 minutes using Zero Heat Flux Thermometry. This study is reported using CONSORT Extension checklist for non-inferiority and equivalence trials. RESULTS: Between December 2016 and October 2018, 129 patients were randomised to receive either Orve+wrap® blanket, (n=65, 50.3%) or Forced Air Warming, (n= 64, 49.7%). The mean 60-minute post-operative temperature of patients receiving Orve+wrap® blanket was 36.2°C and 36.3°C for the patients receiving Forced Air Warming. The predefined non-inferiority margin of a mean difference in temperature of 0.3°C, was not reached between the groups at 60 minutes. Additionally, there were no statistical differences between adverse event rates across these groups. CONCLUSIONS: In the context of this study warming patients with the Orve+wrap® was non-inferior to Forced Air Warming. There were comparable rates of associated post-operative consequences of warming (shivering, hypotension, arrhythmias or surgical site infections), between the groups. RELEVANCE TO CLINICAL PRACTICE: The Orve+wrap® potentially provides an alternative warming method to Forced Air Warming for patients requiring short term post-operative warming. However, there are still a number of unknowns regarding the Orve+wrap® performance and further exploration is required

Intravenous nutrients for preventing inadvertent perioperative hypothermia

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:To estimate the effectiveness of pre‐ or intraoperative intravenous nutrient use in preventing perioperative hypothermia and its complications during surgery in adults

Intravenous nutrients for preventing inadvertent perioperative hypothermia in adults

Background: Inadvertent perioperative hypothermia (a drop in core temperature to below 36°C) occurs because normal temperature regulation is disrupted during surgery, mainly because of the effects of anaesthetic drugs and exposure of the skin for prolonged periods. Many different ways of maintaining body temperature have been proposed, one of which involves administration of intravenous nutrients during the perioperative period that may reduce heat loss by increasing metabolism, thereby increasing heat production. Objectives: To assess the effectiveness of preoperative or intraoperative intravenous nutrients in preventing perioperative hypothermia and its complications during surgery in adults. Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; November 2015) in the Cochrane Library; MEDLINE, Ovid SP (1956 to November 2015); Embase, Ovid SP (1982 to November 2015); the Institute for Scientific Information (ISI) Web of Science (1950 to November 2015); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL, EBSCO host; 1980 to November 2015), as well as the reference lists of identified articles. We also searched the Current Controlled Trials website and ClincalTrials.gov. Selection criteria: Randomized controlled trials (RCTs) of intravenous nutrients compared with control or other interventions given to maintain normothermia in adults undergoing surgery. Data collection and analysis Two review authors extracted data and assessed risk of bias for each included trial, and a third review author checked details if necessary. We contacted some study authors to request additional information. Main results: We included 14 trials (n = 565), 13 (n = 525) of which compared intravenous administration of amino acids to a control (usually saline solution or Ringer's lactate). The remaining trial (n = 40) compared intravenous administration of fructose versus a control. We noted much variation in these trials, which used different types of surgery, variable durations of surgery, and different types of participants. Most trials were at high or unclear risk of bias owing to inappropriate or unclear randomization methods, and to unclear participant and assessor blinding. This may have influenced results, but it is unclear how results might have been influenced. No trials reported any of our prespecified primary outcomes, which were risk of hypothermia and major cardiovascular events. Therefore, we decided to analyse data related to core body temperature instead as a primary outcome. It was not possible to conduct meta‐analysis of data related to amino acid infusion for the 60‐minute and 120‐minute time points, as we observed significant statistical heterogeneity in the results. Some trials showed that higher temperatures were associated with amino acids, but not all trials reported statistically significant results, and some trials reported the opposite result, where the amino acid group had a lower core temperature than the control group. It was possible to conduct meta‐analysis for six studies (n = 249) that provided data relating to the end of surgery. Amino acids led to a statistically significant increase in core temperature in comparison to those receiving control (MD = 0.46°C 95% CI 0.33 to 0.59; I 2 0.0%; random‐effects; moderate quality evidence). Three trials (n = 155) reported shivering as an outcome. Meta‐analysis did not show a clear effect, and so it is uncertain whether amino acids reduce the risk of shivering (RR 0.36, 95% CI 0.13 to 1.00; I 2 = 93%; random‐effects model; very low‐quality evidence). Authors' conclusions: Intravenous amino acids may keep participants up to a half‐degree C warmer than the control. This difference was statistically significant at the end of surgery, but not at other time points. However, the clinical importance of this finding remains unclear. It is also unclear whether amino acids have any effect on the risk of shivering and if intravenous nutrients confer any other benefits or harms, as high‐quality data about these outcomes are lacking. Plain language summary Giving intravenous nutrients to adults during surgery to prevent hypothermia Review question We wanted to find out about the effects that intravenous nutrients (amino acids or sugars given into the bloodstream through a tube or a catheter in a vein) have on adults having surgery. Giving intravenous nutrients increases a person's metabolism, and this may increase the body heat produced. We wanted to know if giving intravenous nutrients during a surgical procedure could keep people warm, and if intravenous nutrients can keep them from having problems caused by being cold. Background People can get cold during surgery, particularly because of the drugs that are used to stop them from feeling pain and that keep them unconscious (anaesthetics). These drugs change how blood flows around the body, which can lead to heart problems and can cause wounds to heal more slowly. It may also cause blood to clot more slowly, and can make some drugs have uncertain effects. People can shiver when they wake from anaesthesia and often comment that this is a very uncomfortable experience. Keeping people warm may stop them from shivering. There are many ways of trying to keep people warm during surgery, including giving them intravenous nutrients. Study characteristics We looked for evidence up to November 2015. We included 14 randomized studies (involving 565 participants). Thirteen studies compared people who received normal care with additional intravenous amino acids against people who received normal care but no amino acids (the control group). One study compared people who received fructose with those in a control group. Studies involved adults undergoing planned or emergency surgery. We did not include studies in which participants were deliberately kept cold during surgery, were receiving skin grafts or were under local anaesthetic. Key results We can be certain that at the end of surgery, people receiving intravenous nutrients are up to a half‐degree warmer than people receiving control (based on evidence from six studies involving 249 participants). However, there was more uncertainty about the effects of intravenous nutrients at other time points, with some studies suggesting that intravenous nutrients keep participants warmer and other studies reporting that participants were colder than those receiving the control. We are uncertain if keeping people up to half a degree warmer is important to those involved in caring for people who are having surgery. We are also uncertain if giving intravenous nutrients reduces the risk of people shivering (based on evidence from three studies involving 155 participants). Quality of the evidence Most of the evidence was moderate to low in quality. The methods used to assign participants to treatment groups was often inadequate or unclear, and we were uncertain if the people assessing outcomes were aware of which treatment group participants were in. This may have biased the results, but we are unsure what effect it may have had on results overall

Thermal insulation for preventing inadvertent perioperative hypothermia

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:To estimate the effectiveness of pre‐ or intraoperative thermal insulation, or both, in preventing perioperative hypothermia and its complications during surgery in adults

Automated monitoring compared to standard care for the early detection of sepsis in critically ill patients

Background: Sepsis is a life‐threatening condition that is usually diagnosed when a patient has a suspected or documented infection, and meets two or more criteria for systemic inflammatory response syndrome (SIRS). The incidence of sepsis is higher among people admitted to critical care settings such as the intensive care unit (ICU) than among people in other settings. If left untreated sepsis can quickly worsen; severe sepsis has a mortality rate of 40% or higher, depending on definition. Recognition of sepsis can be challenging as it usually requires patient data to be combined from multiple unconnected sources, and interpreted correctly, which can be complex and time consuming to do. Electronic systems that are designed to connect information sources together, and automatically collate, analyse, and continuously monitor the information, as well as alerting healthcare staff when pre‐determined diagnostic thresholds are met, may offer benefits by facilitating earlier recognition of sepsis and faster initiation of treatment, such as antimicrobial therapy, fluid resuscitation, inotropes, and vasopressors if appropriate. However, there is the possibility that electronic, automated systems do not offer benefits, or even cause harm. This might happen if the systems are unable to correctly detect sepsis (meaning that treatment is not started when it should be, or it is started when it shouldn't be), or healthcare staff may not respond to alerts quickly enough, or get 'alarm fatigue' especially if the alarms go off frequently or give too many false alarms.Objectives: To evaluate whether automated systems for the early detection of sepsis can reduce the time to appropriate treatment (such as initiation of antibiotics, fluids, inotropes, and vasopressors) and improve clinical outcomes in critically ill patients in the ICU.Search methods: We searched CENTRAL; MEDLINE; Embase; CINAHL; ISI Web of science; and LILACS, clinicaltrials.gov, and the World Health Organization trials portal. We searched all databases from their date of inception to 18 September 2017, with no restriction on country or language of publication.Selection criteria: We included randomized controlled trials (RCTs) that compared automated sepsis‐monitoring systems to standard care (such as paper‐based systems) in participants of any age admitted to intensive or critical care units for critical illness. We defined an automated system as any process capable of screening patient records or data (one or more systems) automatically at intervals for markers or characteristics that are indicative of sepsis. We defined critical illness as including, but not limited to postsurgery, trauma, stroke, myocardial infarction, arrhythmia, burns, and hypovolaemic or haemorrhagic shock. We excluded non‐randomized studies, quasi‐randomized studies, and cross‐over studies . We also excluded studies including people already diagnosed with sepsis.Data collection and analysis: We used the standard methodological procedures expected by Cochrane. Our primary outcomes were: time to initiation of antimicrobial therapy; time to initiation of fluid resuscitation; and 30‐day mortality. Secondary outcomes included: length of stay in ICU; failed detection of sepsis; and quality of life. We used GRADE to assess the quality of evidence for each outcome.Main results: We included three RCTs in this review. It was unclear if the RCTs were three separate studies involving 1199 participants in total, or if they were reports from the same study involving fewer participants. We decided to treat the studies separately, as we were unable to make contact with the study authors to clarify.All three RCTs are of very low study quality because of issues with unclear randomization methods, allocation concealment and uncertainty of effect size. Some of the studies were reported as abstracts only and contained limited data, which prevented meaningful analysis and assessment of potential biases.The studies included participants who all received automated electronic monitoring during their hospital stay. Participants were randomized to an intervention group (automated alerts sent from the system) or to usual care (no automated alerts sent from the system).Evidence from all three studies reported 'Time to initiation of antimicrobial therapy'. We were unable to pool the data, but the largest study involving 680 participants reported median time to initiation of antimicrobial therapy in the intervention group of 5.6 hours (interquartile range (IQR) 2.3 to 19.7) in the intervention group (n = not stated) and 7.8 hours (IQR 2.5 to 33.1) in the control group (n = not stated).No studies reported 'Time to initiation of fluid resuscitation' or the adverse event 'Mortality at 30 days'. However very low‐quality evidence was available where mortality was reported at other time points. One study involving 77 participants reported 14‐day mortality of 20% in the intervention group and 21% in the control group (numerator and denominator not stated). One study involving 442 participants reported mortality at 28 days, or discharge was 14% in the intervention group and 10% in the control group (numerator and denominator not reported). Sample sizes were not reported adequately for these outcomes and so we could not estimate confidence intervals.Very low‐quality evidence from one study involving 442 participants reported 'Length of stay in ICU'. Median length of stay was 3.0 days in the intervention group (IQR = 2.0 to 5.0), and 3.0 days (IQR 2.0 to 4.0 in the control).Very low‐quality evidence from one study involving at least 442 participants reported the adverse effect 'Failed detection of sepsis'. Data were only reported for failed detection of sepsis in two participants and it wasn't clear which group(s) this outcome occurred in.No studies reported 'Quality of life'.Authors' conclusions:It is unclear what effect automated systems for monitoring sepsis have on any of the outcomes included in this review. Very low‐quality evidence is only available on automated alerts, which is only one component of automated monitoring systems. It is uncertain whether such systems can replace regular, careful review of the patient's condition by experienced healthcare staff

Thermal insulation for preventing inadvertent perioperative hypothermia

- Background Inadvertent perioperative hypothermia occurs because of interference with normal temperature regulation by anaesthetic drugs and exposure of skin for prolonged periods. A number of different interventions have been proposed to maintain body temperature by reducing heat loss. Thermal insulation, such as extra layers of insulating material or reflective blankets, should reduce heat loss through convection and radiation and potentially help avoid hypothermia. Objectives To assess the effects of pre‐ or intraoperative thermal insulation, or both, in preventing perioperative hypothermia and its complications during surgery in adults. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) ( The Cochrane Library 2014, Issue 2), MEDLINE, OvidSP (1956 to 4 February 2014), EMBASE, OvidSP (1982 to 4 February 2014), ISI Web of Science (1950 to 4 February 2014), and CINAHL, EBSCOhost (1980 to 4 February 2014), and reference lists of articles. We also searched Current Controlled Trials and ClinicalTrials.gov. Selection criteria Randomized controlled trials of thermal insulation compared to standard care or other interventions aiming to maintain normothermia. Data collection and analysis Two authors extracted data and assessed risk of bias for each included study, with a third author checking details. We contacted some authors to ask for additional details. We only collected adverse events if reported in the trials. Main results We included 22 trials, with 16 trials providing data for some analyses. The trials varied widely in the type of patients and operations, the timing and measurement of temperature, and particularly in the types of co‐interventions used. The risk of bias was largely unclear, but with a high risk of performance bias in most studies and a low risk of attrition bias. The largest comparison of extra insulation versus standard care had five trials with 353 patients at the end of surgery and showed a weighted mean difference (WMD) of 0.12 ºC (95% CI ‐0.07 to 0.31; low quality evidence). Comparing extra insulation with forced air warming at the end of surgery gave a WMD of ‐0.67 ºC (95% CI ‐0.95 to ‐0.39; very low quality evidence) indicating a higher temperature with forced air warming. Major cardiovascular outcomes were not reported and so were not analysed. There were no clear effects on bleeding, shivering or length of stay in post‐anaesthetic care for either comparison. No other adverse effects were reported. Authors' conclusions There is no clear benefit of extra thermal insulation compared with standard care. Forced air warming does seem to maintain core temperature better than extra thermal insulation, by between 0.5 ºC and 1 ºC, but the clinical importance of this difference is unclear. Plain language summary Insulation for preventing hypothermia during operations Review question We wanted to find out the effects of extra insulation on preventing hypothermia and its complications for adults having an operation. Background People can get cold during operations, particularly because of the drugs used as anaesthetics. This can sometimes cause potentially dangerous heart problems. The cold can also make people shiver and feel uncomfortable after an operation. Ways have therefore been developed to try to keep people warm during an operation. One way is to use reflective blankets or clothing as extra insulation. Study characteristics We looked at the evidence up to February 2014 and found 22 studies involving several hundred patients. The studies involved people aged over 18 years having routine or emergency surgery. We disregarded studies where people were deliberately kept cold during the operation, where they were having head surgery or skin grafts, or where the person was having a procedure under local anaesthetic. We looked at studies comparing what happened when using reflective blankets or clothing against what happened when someone had normal care, using non‐reflective blankets or clothing. We also looked at studies comparing w at happened when using a machine to force warm air through the person’s blankets (forced air warming) against what happened when using reflective blankets or clothing. Key results There is no clear evidence that using reflective blankets or clothing increases a person’s temperature compared with what happens when someone has usual care. There is some evidence that using forced air warming increases a person’s temperature compared with what happens when using reflective blankets or clothing. The temperature increase was between 0.5 ºC and 1 ºC. It is unclear how this temperature difference would reduce the consequences of coldness, with uncertain effects on blood loss, shivering and time spent in recovery. We were unable to find sufficient information to look at adverse effects of insulation or warming, or major events affecting the heart or circulatory system. Quality of the evidence Most of the evidence was low quality. We were particularly concerned about the potential for skewed results from operating theatre staff changing their behaviour when they knew ways of keeping the patient warm had changed