Estimation of the maximum potential cost saving from reducing serious adverse events in hospitalized patients.

PURPOSE: The increasing use of advanced medical technologies to detect adverse events, for instance, artificial intelligence-assisted technologies, has shown promise in improving various aspects within health care but may also come with substantial expenses. Therefore, understanding the potential economic benefits can guide decision-making processes regarding implementation. We aimed to estimate the potential cost savings associated with reducing length of stay and avoiding readmissions within the framework of an artificial intelligence-assisted vital signs monitoring system. METHODS: We used data from Danish national registries and coarsened exact matching to estimate the difference in length of stay and probability of readmission among adult in-hospital patients exposed to and not exposed to serious adverse events. We used these estimates to calculate the maximum potential savings that could be achieved by early detection of adverse events to reduce length of stay and avoid readmissions. RESULTS: Patients exposed to serious adverse events during admission had 2.4 (95% CI: 2.4-2.5) additional hospital bed days and had 14% (95% CI 11%-17%) higher odds of readmissions compared with patients not exposed to such events. A base case scenario yielded maximum potential savings if one patient avoided a serious adverse event of EUR 2040 due to reduced length of stay and EUR 43 due to avoidance of readmissions caused by serious adverse events. CONCLUSION: Reductions in serious adverse events are associated with decreased healthcare costs due to reduced length of stay and avoided readmissions. Artificial intelligence-assisted vital signs monitoring systems are one potential approach to reduce serious adverse events, however, the ability of this technology to reduce adverse events remains unclear. Comprehensive prospective analyses of such systems including the intervention and implementation costs are necessary to understand their full economic impact.

Workload associated with manual assessment of vital signs as compared with continuous wireless monitoring.

BACKGROUND: Vital sign monitoring is considered an essential aspect of clinical care in hospitals. In general wards, this relies on intermittent manual assessments performed by clinical staff at intervals of up to 12 h. In recent years, continuous monitoring of vital signs has been introduced to the clinic, with improved patient outcomes being one of several potential benefits. The aim of this study was to determine the workload difference between continuous monitoring and manual monitoring of vital signs as part of the National Early Warning Score (NEWS). METHODS: Three wireless sensors continuously monitored blood pressure, heart rate, respiratory rate, and peripheral oxygen saturation in 20 patients admitted to the general hospital ward. The duration needed for equipment set-up and maintenance for continuous monitoring in a 24-h period was recorded and compared with the time spent on manual assessments and documentation of vital signs performed by clinical staff according to the NEWS. RESULTS: The time used for continuous monitoring was 6.0 (IQR 3.2; 7.2) min per patient per day vs. 14 (9.7; 32) min per patient per day for the NEWS. Median difference in duration for monitoring of vital signs was 9.9 (95% CI 5.6; 21) min per patient per day between NEWS and continuous monitoring (p < .001). Time used for continuous monitoring in isolated patients was 6.6 (4.6; 12) min per patient per day as compared with 22 (9.7; 94) min per patient per day for NEWS. CONCLUSION: The use of continuous monitoring was associated with a significant reduction in workload in terms of time for monitoring as compared with manual assessment of vital signs.

Wireless continuous single-lead ST-segment monitoring to detect new-onset myocardial injury at the general ward-An exploratory subanalysis.

Patients admitted for acute medical conditions and major noncardiac surgery are at risk of myocardial injury. This is frequently asymptomatic, especially in the context of concomitant pain and analgesics, and detection thus relies on cardiac biomarkers. Continuous single-lead ST-segment monitoring from wireless electrocardiogram (ECG) may enable more timely intervention, but criteria for alerts need to be defined to reduce false alerts. This study aimed to determine optimal ST-deviation thresholds from wireless single-lead ECG for detection of myocardial injury following major abdominal cancer surgery and during acute exacerbation of chronic obstructive pulmonary disease. Patients were monitored with a wireless single-lead ECG patch for up to 4 days and had daily troponin measurements. Single-lead ST-segment deviations of <0.255 mV and/or >0.245 mV (based on previous study comparison with 0.1 mV 12-lead ECG and variation in single-lead ECG) were analyzed for relation to myocardial injury defined as hsTnT elevation of 20-64 ng/L with an absolute change of ≥5 ng/L, or a hsTnT level ≥ 65 ng/L. In total, 528 patients were included for analysis, of which 15.5% had myocardial injury. For corrected ST-thresholds lasting ≥10 and ≥ 20 min, we found specificities of 91% and 94% and sensitivities of 17% and 13% with odds ratios of 2.0 (95% CI: 1.1; 3.9) and 2.4 (95% CI: 1.1; 5.1) for myocardial injury. In conclusion, wireless single-lead ECG monitoring with corrected ST thresholds detected patients developing myocardial injury with specificities >90% and sensitivities <20%, suggesting increased focus on sensitivity improvement.

Opioids and personalized analgesia in the perioperative setting: A protocol for five systematic reviews.

BACKGROUND: Treatment with opioids is a mainstay in perioperative pain management. While the leading treatment paradigm has been procedure-specific pain management, efforts regarding personalized pain treatment are increasing. The OPI•AID project aims to develop personalized algorithms for perioperative pain management, taking demographic, surgical, and anaesthesiologic factors into account. We will undertake five parallel reviews to illuminate current evidence on different aspects of individual responses to perioperative opioid treatment. METHODS: Inclusion of adult populations in English-written studies. Review-specific searches are developed for the following databases: CENTRAL, MEDLINE, Embase, clinicaltrials.gov, and clinicaltrial.eu. Two authors will independently screen citations, extract data, and assess the risks of bias in each review (QUIPS, PROBAST and RoB2, as relevant). CONCLUSION: These reviews will evaluate various aspects of perioperative opioid treatment, including individualized treatment strategies, selection of specific opioids, and individual patient responses. These will guide future development of a personalized perioperative opioid treatment algorithm (OPI•AID) that will be validated and tested clinically against standard of care.

Comparison of Wireless Continuous Axillary and Core Temperature Measurement after Major Surgery.

BACKGROUND: Temperature is considered one of the primary vital signs for detection of complications such as infections. Continuous wireless real-time axillary temperature monitoring is technologically feasible at the general ward, but no clinical validation studies exist. METHODS: This study compared axillary temperature with a urinary bladder thermometer in 40 major abdominal postoperative patients. The primary outcome was changes in axillary temperature registrations. Secondary outcomes were mean bias between the urinary bladder and the axillary temperatures. Intermittent frontal and tympanic temperature recordings were also collected. RESULTS: Forty patients were monitored for 50 min with an average core temperature of 36.8 °C. The mean bias was -1.0 °C (LoA -1.9 to -0) after 5 min, and -0.8 °C (LoA -1.6 to -0.1) after 10 min when comparing the axillary temperature with the urinary bladder temperature. After 20 min, the mean bias was -0.6 °C (LoA -1.3-0.1). During upper arm abduction, the axilla temperature was reduced to -1.6 °C (LoA -2.9 to -0.3) within 1 min. Temporal skin temperature measurement had a resulted in a mean bias of -0.1 °C (LOA -1.1 to -1.0) compared with central temperature. Compared with the mean tympanic temperature, it was -0.1 °C (LoA -0.9 to -1.0) lower than the urinay bladder temperature. CONCLUSIONS: Axillary temperature increased with time, reaching a mean bias of 1 °C between axillary and core temperature within 5 min. Opening the axillary resulted in rapidly lower temperature recordings. These findings may aid in use and designing corrections for continuous axillary temperature monitoring.

Experiences of isolation in patients in the intensive care unit during the COVID-19 pandemic.

BACKGROUND: During the COVID-19 pandemic, patients in the intensive care unit have been subjected to strict isolation precautions, and potentially long and complicated patient courses. The aim of the study is to provide an investigation of the experiences of isolation in COVID-19-positive patients in the ICU during the first phase of the COVID-19 pandemic in Denmark. METHODS: The study was performed in a 20-bed ICU at a university hospital in Copenhagen, Denmark. The study is based on a phenomenological framework, Phenomenologically Grounded Qualitative Research. This approach provides insights into the tacit, pre-reflective and embodied dimensions of the specific experience under investigation. Methods included a combination of in-depth structured interviews with ICU patients 6-12 months after ICU discharge, and observations from inside the isolated patient rooms. The descriptions of experiences gathered through the interviews were subjected to systematic thematic analysis. RESULTS: Twenty-nine patients were admitted to the ICU in the period 10 March and 19 May 2020. A total of six patients was included in the study. Themes consistently reported across all patients included (1) being objectified to degrees that implied self-alienation; (2) feeling a sense of being in captivity; (3) being in an experiential state of surrealism, and finally (4) experiencing extreme loneliness and intercorporeal deprivation. CONCLUSION: This study provided further insights into the liminal patient experiences of being isolated in the ICU due to COVID-19. Robust themes of experience were achieved through an in-depth phenomenological approach. Although, similarities in experiences compared to other patient groups exist, the precarious situation constituted by COVID-19 lead to significant intensifications across multiple parameters.

Continuous wireless pre- and postoperative vital sign monitoring reveal new, severe desaturations after vascular surgery.

OBJECTIVES: Postoperative deviating physiologic values (vital signs) may represent postoperative stress or emerging complications. But they can also reflect chronic preoperative values. Distinguishing between the two circumstances may influence the utility of using vital signs in patient monitoring. Thus, we aimed to describe the occurrence of vital sign deviations before and after major vascular surgery, hypothesising that preoperative vital sign deviations were longer in duration postoperatively. METHODS: In this prospective observational study, arterial vascular patients were continuously monitored wirelessly - from the day before until 5 days after surgery. Recorded values were: heart rate, respiration rate, peripheral arterial oxygen saturation (SpO2 ) and blood pressure. The outcomes were 1. cumulative duration of SpO2 < 85% / 24 h, and 2. cumulative duration per 24 h of vital sign deviations. RESULTS: Forty patients were included with a median monitoring time of 21 h preoperatively and 42 h postoperatively. The median duration of SpO2 < 85% preoperatively was 14.4 min/24 h whereas it was 28.0 min/24 h during day 0 in the ward (p = .09), and 16.8 min/24 h on day 1 in the ward (p = 0.61). Cumulative duration of SpO2 < 80% was significantly longer on day 0 in the ward 2.4 min/24 h (IQR 0.0-4.6) versus 6.7 min/24 h (IQR 1.8-16.2) p = 0.01. CONCLUSION: Deviating physiology is common in patients before and after vascular surgery. A longer duration of severe desaturation was found on the first postoperative day in the ward compared to preoperatively, whereas moderate desaturations were reflected in postoperative desaturations. Cumulative duration outside thresholds is, in some cases, exacerbated after surgery.

Continuous monitoring is superior to manual measurements in detecting vital sign deviations in patients with COVID-19.

BACKGROUND: Patients admitted to the emergency care setting with COVID-19-infection can suffer from sudden clinical deterioration, but the extent of deviating vital signs in this group is still unclear. Wireless technology monitors patient vital signs continuously and might detect deviations earlier than intermittent measurements. The aim of this study was to determine frequency and duration of vital sign deviations using continuous monitoring compared to manual measurements. A secondary analysis was to compare deviations in patients admitted to ICU or having fatal outcome vs. those that were not. METHODS: Two wireless sensors continuously monitored (CM) respiratory rate (RR), heart rate (HR), and peripheral arterial oxygen saturation (SpO2 ). Frequency and duration of vital sign deviations were compared with point measurements performed by clinical staff according to regional guidelines, the National Early Warning Score (NEWS). RESULTS: SpO2 < 92% for more than 60 min was detected in 92% of the patients with CM vs. 40% with NEWS (p < .00001). RR > 24 breaths per minute for more than 5 min were detected in 70% with CM vs. 33% using NEWS (p = .0001). HR ≥ 111 for more than 60 min was seen in 51% with CM and 22% with NEWS (p = .0002). Patients admitted to ICU or having fatal outcome had longer durations of RR > 24 brpm (p = .01), RR > 21 brpm (p = .01), SpO2 < 80% (p = .01), and SpO2 < 85% (p = .02) compared to patients that were not. CONCLUSION: Episodes of desaturation and tachypnea in hospitalized patients with COVID-19 infection are common and often not detected by routine measurements.

Deviations in continuously monitored electrodermal activity before severe clinical complications: a clinical prospective observational explorative cohort study.

Monitoring of high-risk patients in hospital wards is crucial in identifying and preventing clinical deterioration. Sympathetic nervous system activity measured continuously and non-invasively by Electrodermal activity (EDA) may relate to complications, but the clinical use remains untested. The aim of this study was to explore associations between deviations of EDA and subsequent serious adverse events (SAE). Patients admitted to general wards after major abdominal cancer surgery or with acute exacerbation of chronic obstructive pulmonary disease were continuously EDA-monitored for up to 5 days. We used time-perspectives consisting of 1, 3, 6, and 12 h of data prior to first SAE or from start of monitoring. We constructed 648 different EDA-derived features to assess EDA. The primary outcome was any SAE and secondary outcomes were respiratory, infectious, and cardiovascular SAEs. Associations were evaluated using logistic regressions with adjustment for relevant confounders. We included 714 patients and found a total of 192 statistically significant associations between EDA-derived features and clinical outcomes. 79% of these associations were EDA-derived features of absolute and relative increases in EDA and 14% were EDA-derived features with normalized EDA above a threshold. The highest F1-scores for primary outcome with the four time-perspectives were 20.7-32.8%, with precision ranging 34.9-38.6%, recall 14.7-29.4%, and specificity 83.1-91.4%. We identified statistically significant associations between specific deviations of EDA and subsequent SAE, and patterns of EDA may be developed to be considered indicators of upcoming clinical deterioration in high-risk patients.

Simulation-Based Education of Endovascular Scrub Nurses Reduces Stress and Improves Team Performance.

INTRODUCTION: Endovascular procedures have become commonplace in vascular surgery. This development calls for new training strategies for future specialists. Most simulation-based education (SBE) programs have a monodisciplinary focus on physicians, although successful surgery is a multidisciplinary team effort. Mental stress impairs the learning process and surgical performance and heart rate variability (HRV) can be measured as a proxy for both mental and physical stress. This study aims to assess how SBE of endovascular scrub nurses affects team performance and HRV during endovascular aneurysm repair (EVAR). MATERIALS AND METHODS: Prospective interventional study in which EVAR-inexperienced scrub nurses followed a focused SBE EVAR program. During real-life EVAR procedures, HRV was continuously recorded with a wireless electrocardiogram patch and multidisciplinary team performance was assessed with the Imperial College Error CAPture (ICECAP) tool, before and after the SBE program, allowing each scrub nurse to serve as their own control. Eight scrub nurses with experience in lower limb endovascular procedures, but not EVAR, were invited to participate. RESULTS: Seven participants completed the study. In five of seven scrub nurses, HRV-derived stress levels during real-time EVAR procedures were lower after SBE compared to before SBE. Mean HRV increased from 24 msec to 35 msec (P < 0.001), indicating stress level reduction. Before SBE, the mean number of errors/hour was 7.3 (standard deviation ± 1.8) compared to 3.6 (standard deviation ± 2.7) after SBE. Most errors were categorized as technical (58 %) and communicative (23 %). CONCLUSIONS: SBE of scrub nurses may improve team performance and may lower mental stress during EVAR procedures. In this small study, we suggest using mental stress, as evaluated with HRV, and multidisciplinary team performance, as evaluated with ICECAP, to assess SBE effectiveness in real-case EVAR procedures. This SBE program and live ICECAP observations and electrocardiogram patches was well-accepted by scrub nurses and the entire team.

The use of melatonin in Danish intensive care departments-A nationwide observational study.

BACKGROUND: Melatonin is widely employed as a hypnotic in various patient groups. In intensive care patients, melatonin seems to be increasingly used due to potential clinical effects and a favourable safety profile. OBJECTIVES: We aimed to investigate the extend of usage and clinical practice of melatonin therapy in intensive care departments in Denmark. DESIGN: Data from regional hospital pharmacies and the Danish Intensive Care Database were used to estimate defined daily dose and defined daily dose per 1000 ICU admission days. Also, related expenses in the period 2015-2019. Finally, a questionnaire describing the clinical practice of melatonin therapy was provided to all Danish intensive care departments. PRINCIPAL OBSERVATIONS: The usage of melatonin in intensive care departments in Denmark increased from 21,300 DDD (200.0 DDD per 1000 ICU admission days) in 2015 to 52,170 DDD (560.7 DDD per 1000 ICU admission days) in 2019. A total of 32 ICU departments participated in the study (97% of all Danish ICU departments). All included ICU departments employed melatonin as a hypnotic. Nineteen percent of included departments administered melatonin to all admitted patients, whereas 25% of departments rarely administered melatonin. Magistral melatonin 3-mg tablets was the most employed drug dose/formulation. Increased doses of melatonin were administered in selected patients. Melatonin was considered safe by prescribing clinicians. CONCLUSIONS: Melatonin is widely and increasingly used in Danish intensive care departments. The more than doubled usage of melatonin in the study period advocates for further studies employing validated outcomes of sleep and other patient-relevant outcomes. EDITORIAL COMMENT: This study documents that melatonin is frequently used as a hypnotic in Danish intensive care units during recent years despite a shortage of reliable evidence to support a recommendation to treat with melatonin in this context. These results support a need for conducting clinical trials to determine whether or not there is a beneficial effect of melatonin treatment in critically ill patients.

Effect of dexamethasone on intraoperative remifentanil dose in total knee arthroplasty surgery under general anaesthesia.

BACKGROUND: The effects of glucocorticoids may include both genomic and rapid nongenomic effects. The potential rapid analgesic effect during surgery has not previously been investigated. We aimed to explore the effect of dexamethasone on intraoperative infusion rate of remifentanil in patients undergoing total knee arthroplasty (TKA) surgery under general anaesthesia. METHODS: In this post hoc subgroup analysis, we included patients randomised in the DEX-2-TKA trial, who were operated under total intravenous anaesthesia with remifentanil and propofol. Trial medication, intravenous dexamethasone 24 mg or placebo, was administered immediately after anaesthesia onset. The primary outcome was the median weight-corrected infusion rate of remifentanil during surgery. Secondary outcomes included median weight-corrected infusion rate of propofol, median intraoperative bispectral index and time spent in the post-anaesthesia care unit. RESULTS: Eighty-seven patients were included in the analysis of the primary outcome. A significantly higher remifentanil infusion rate was observed in the dexamethasone group compared with the placebo group, p = .02. None of the secondary outcomes resulted in statistically significant differences between groups. CONCLUSION: This explorative post hoc analysis of the randomised DEX-2-TKA trail showed that patients undergoing TKA surgery under general anaesthesia and who received dexamethasone seemed to have a higher remifentanil infusion rate compared with patients who received placebo. The clinical implications of the potentially increased remifentanil infusion rate need to be validated and explored further. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05002361 (12 August 2021).

Transcutaneous blood gas monitoring and tissue perfusion during common femoral thromboendarterectomy.

BACKGROUND: Improving tissue perfusion can improve clinical outcomes in surgical patients, where monitoring may aid clinicians in detecting adverse conditions and guide interventions. Transcutaneous monitoring (TCM) of oxygen (tcpO2) and carbon dioxide (tcpCO2) is a well-proven technology and could potentially serve as a measure of local circulation, perfusion and metabolism, but the clinical use is not thoroughly explored. The purpose of this proof-of-concept study was to investigate whether TCM of blood gasses could detect changes in perfusion during major vascular surgery. METHODS: Ten patients with peripheral arterial disease scheduled for lower limb major arterial revascularization under general anaesthesia were consecutively included. TcpO2 and tcpCO2 were continuously recorded from anaesthesia induction until skin closure with a TCM monitor placed on both legs and the thorax. Peripheral oxygen saturation was kept ≥94% and mean arterial blood pressure ≥65 mmHg. The primary outcomes were changes in tcpO2 and tcpCO2 related to arterial clamping and declamping during the procedure and analyzed by paired statistics. RESULTS: Femoral artery clamping resulted in a significant decrease in tcpO2 (-2.1 kPa, IQR-4.2; -0.8), p=.017)), followed by a significant increase in response to arterial declamping (5.5 kPa, IQR 0-7.3), p=.017)). Arterial clamping resulted in a statistically significant increase in tcpCO2 (0.9 kPa, IQR 0.3-5.4), p=.008)) and a significant decrease following declamping (-0.7 kPa, IQR -2.6; -0.2), p=.011)). CONCLUSION: Transcutaneous monitoring of oxygen and carbon dioxide is a feasible method for detection of extreme changes in tissue perfusion during arterial clamping and declamping, and its use for improving patient outcomes should be explored. Clinical Trials identifier: NCT04040478. Registered on July 31, 2019.

The Impact of Intraoperative Fluid Therapy and Body Temperature on Surgical Site Infection - Re-Assessment of a Randomized Trial.

Background: Use of supplemental oxygen during surgery to reduce the incidence of SSI was investigated in the PROXI trial, which found no reduced frequency of SSI. Subsequently, it has been suggested that a restrictive fluid regimen and hypothermia in some patients could explain why no beneficial effect of supplemental oxygen was found. We evaluated the association between the occurrence of SSI and two perioperative factors, volume of infused fluid and body temperature (BT). Methods: We used data from the PROXI trial including 1,386 patients undergoing laparotomy randomly assigned to receive 80% or 30% oxygen during surgery. A fluid infusion index (FII) was calculated for each patient as the volume of infused fluids/body weight/duration of surgery. Results: SSI occurred in 18.9% of the patients in the lower FII tertile group (OR=0.86; P=0.41), in 20.4% in the upper FII tertile group (OR=1.49; P=0.05), in 19.7% of the patients with hypothermia (OR=1.28; P=0.25) and in 25.0% with hyperthermia (OR=1.26; P=0.52). An increased risk of SSI (OR=3.15; P=0.01) was found in patients having both hypothermia and emergency surgery. CONCLUSION: A trend towards an increased risk of SSI was seen in patients who received a greater volume of intravenous fluid. No association was found between BT and SSI.

Intensive care nurses' experiences of caring for isolated COVID-positive patients during first wave of COVID-19.

Background: COVID-19 has fundamentally changed all fields of health care. Intensive care nurses have been at the forefront of the pandemic facing the massive impact of the disease, both professionally and personally. This study investigated nurses' experiences of caring for isolated COVID-19 positive patients in the intensive care department during the first wave of the COVID-19 pandemic. The study investigated how isolation affected the nurses themselves, how they related with their patients, and how isolation affected patient care in general. Methods: The study was performed at a 20-bed university hospital intensive care department in Copenhagen, Denmark. COVID-19 positive patients were isolated or cohort isolated. A dedicated nurse cared for each isolated patient and wore full personal protective equipment. The study is based on in-depth phenomenological interviews with intensive care nurses conducted in summer 2020. The interviews were structured according to the principles of "Phenomenologically Grounded Qualitative Research." The data included observations from within the isolated patient rooms. Findings: Six intensive care nurses participated in the study. The analysis documented following themes consistently reported by all nurses: (1) a general sense of uncanniness, (2) intense feelings of confinement and co-isolation, and (3) heightened senses of bodily objectification, including how nurses' experienced their patients and also themselves. Conclusion: This is the first Scandinavian phenomenological study to focus on mapping the experiences of intensive care nurses during the extreme circumstances of the first wave of the COVID-19 pandemic. Further studies may explore long-term effects, such as psychiatric morbidity or psychological functioning in these individuals.

The effect of technical filtering and clinical criteria on alert rates from continuous vital sign monitoring in the general ward.

OBJECTIVES: Continuous vital sign monitoring at the general hospital ward has major potential advantages over intermittent monitoring but generates many alerts with risk of alert fatigue. We hypothesized that the number of alerts would decrease using different filters. METHODS: This study was an exploratory analysis of the alert reducing effect from adding two different filters to continuously collected vital sign data (peripheral oxygen saturation, blood pressure, heart rate, and respiratory rate) in patients admitted after major surgery or severe medical disease. Filtered data were compared to data without artifact removal. Filter one consists of artifact removal, filter two consists of artifact removal plus duration criteria adjusted for severity of vital sign deviation. Alert thresholds were based on the National Early Warning Score (NEWS) threshold. RESULTS: A population of 716 patients admitted for severe medical disease or major surgery with continuous wireless vital sign monitoring at the general ward with a mean monitoring time of 75.8 h, were included for the analysis. Without artifact removal, we found a median of 137 [IQR: 87-188] alerts per patient/day, artifact removal resulted in a median of 101 [IQR: 56-160] alerts per patient/day and with artifact removal combined with a duration-severity criterion, we found a median of 19 [IQR: 9-34] alerts per patient/day. Reduction of alerts was 86.4% (p < 0.001) for values without artifact removal (137 alerts) vs. the duration criteria and a reduction (19 alerts) of 81.5% (p < 0.001) for the criteria with artifact removal (101 alerts) vs. the duration criteria (19 alerts). CONCLUSION: We conclude that a combination of artifact removal and duration-severity criteria approach substantially reduces alerts generated by continuous vital sign monitoring.

Letter the editor: serious methodological concerns about a recently published meta-analysis on oxygen therapy.

In a recent paper, Chen et al. report the findings of a systematic review with meta-analysis concerning conservative versus conventional oxygen therapy for critically ill patients. We wish to commend the authors for their interest in the matter. However, the authors appear to misquote findings, fail to report results for all specified analyses, do not identify all relevant trials, have post hoc changed the eligibility criteria, and have seemingly switched directions of effects in analyses of secondary outcomes. These issues have led to incorrect conclusions concerning the effects of targeted oxygen therapy in critically ill patients.

Waking Up in Pain: a prospective unselected cohort study of pain in 3702 patients immediately after surgery in the Danish Realm.

BACKGROUND: Acute and persistent pain after surgery is well described. However, no large-scale studies on immediate postoperative pain in the operating room (OR) exist, hindering potential areas of research to improve clinical outcomes. Thus, we aimed to describe the occurrence and severity of immediate postoperative pain in a large, unselected cohort. METHODS: This was a prospective cohort study, encompassing all procedures in 31 public hospitals in the Danish Realm, during a 5-day period including the weekend. Data on procedures and anesthesia were collected and the main outcome was occurrence of moderate or severe pain in the OR. Secondary outcomes included pain, sedation and nausea in the OR or during the first 15 min in the postanesthesia care unit (PACU) including relevant risk factors. Descriptive and logistic regression statistics were used. RESULTS: A total of 3675 procedures were included for analysis (87% inclusion rate). Moderate or severe pain occurred in 7.4% (95% CI 6.5% to 8.3%) of cases in the OR immediately after awakening, rising to 20.2% in the OR and/or PACU. Large intraprocedure and interprocedure variations occurred (0.0%-37.5%), and in 20% of cases with epidural-general anesthesia patients experienced moderate or severe pain. Independent risk factors were female sex, younger age, preoperative pain, daily opioid use and major surgical procedures. CONCLUSION: Moderate or severe pain in the immediate postoperative phase occurred in 20% of all cases with procedure and anesthesiological technique variations, suggesting a need for identification of relevant procedure-specific risk factors and development of preventive treatments. TRIAL REGISTRATION NUMBER: RoPR ID 43191.

High incidence of chronic pain following surgery for pelvic fracture.

OBJECTIVES: To determine the incidence of chronic pain after surgery for pelvic fracture using a strict definition and measures of intensity and health-related quality of life. METHODS: In April 2004, a questionnaire was sent to 221 patients who underwent surgery for pelvic fracture in the period 1996 to 2000. Chronic pain was defined as pain at present that related back to the pelvic fracture and was not a consequence of other disease. Health-related quality of life was measured using the 15D questionnaire. RESULTS: The response rate was 72.9% after a median follow-up of 5.6 years. Chronic pain was seen in 48.4% (95% confidence interval, 40.7%-56.2%). These patients had a combination of somatic nociceptive, visceral nociceptive, and neuropathic pain and had significantly lower health-related quality of life. Also, the use of opioids (14.1% vs. 4.8%) and nonsteroidal anti-inflammatories/paracetamol (57.7% vs. 21.7%), the request for financial compensation (75.6% vs. 45.8%), and complications related to leg function (62.8% vs. 20.5%) were significantly higher in the group with chronic pain than in the group without chronic pain. CONCLUSIONS: Chronic pain after pelvic fracture is a major problem that affects a patient's quality of life. The use of analgesics was higher in these patients, and they had more complications. Chronic pain after surgery for pelvic fracture deserves more attention.