Prescribed hypocaloric nutrition support for critically‐ill adults

This Cochrane Systematic Review by Perman and colleagues was published in June 2018.  The full text of the systematic review is available via this link.

Background:  There are controversies about the amount of calories and thecochrane-57-1 type of nutritional support that should be given to critically‐ill people. Several authors advocate the potential benefits of hypocaloric nutrition support, but the evidence is inconclusive.

Objectives:  To assess the effects of prescribed hypocaloric nutrition support in comparison with standard nutrition support for critically‐ill adults.

Search methods:  We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Cochrane Library), MEDLINE, Embase and LILACS (from inception to 20 June 2017) with a specific strategy for each database. We also assessed three websites, conference proceedings and reference lists, and contacted leaders in the field and the pharmaceutical industry for undetected/unpublished studies. There was no restriction by date, language or publication status.
Selection criteria:  We included randomized and quasi‐randomized controlled trials comparing hypocaloric nutrition support to normo‐ or hypercaloric nutrition support or no nutrition support (e.g. fasting) in adults hospitalized in intensive care units (ICUs).
Data collection and analysis:  We used standard methodological procedures expected by Cochrane. We meta‐analysed data for comparisons in which clinical heterogeneity was low. We conducted pre-specified subgroup and sensitivity analyses, and post hoc analyses, including meta‐regression. Our primary outcomes were: mortality (death occurred during the ICU and hospital stay, or 28‐ to 30‐day all‐cause mortality); length of stay (days stayed in the ICU and in the hospital); and Infectious complications. Secondary outcomes included: length of mechanical ventilation. We assessed the quality of evidence with GRADE.
Main results:  We identified 15 trials, with a total of 3129 ICU participants from university‐associated hospitals in the USA, Colombia, Saudi Arabia, Canada, Greece, Germany and Iran. There are two ongoing studies. Participants suffered from medical and surgical conditions, with a variety of inclusion criteria. Four studies used parenteral nutrition and nine studies used only enteral nutrition; it was unclear whether the remaining two used parenteral nutrition. Most of them could not achieve the proposed caloric targets, resulting in small differences in the administered calories between intervention and control groups. Most studies were funded by the US government or non‐governmental associations, but three studies received funding from industry. Five studies did not specify their funding sources.
The included studies suffered from important clinical and statistical heterogeneity. This heterogeneity did not allow us to report pooled estimates of the primary and secondary outcomes, so we have described them narratively.
When comparing hypocaloric nutrition support with a control nutrition support, for hospital mortality (9 studies, 1775 participants), the risk ratios ranged from 0.23 to 5.54; for ICU mortality (4 studies, 1291 participants) the risk ratios ranged from 0.81 to 5.54, and for mortality at 30 days (7 studies, 2611 participants) the risk ratios ranged from 0.79 to 3.00. Most of these estimates included the null value. The quality of the evidence was very low due to unclear or high risk of bias, inconsistency and imprecision.
Participants who received hypocaloric nutrition support compared to control nutrition support had a range of mean hospital lengths of stay of 15.70 days lower to 10.70 days higher (10 studies, 1677 participants), a range of mean ICU lengths of stay 11.00 days lower to 5.40 days higher (11 studies, 2942 participants) and a range of mean lengths of mechanical ventilation of 13.20 days lower to 8.36 days higher (12 studies, 3000 participants). The quality of the evidence for this outcome was very low due to unclear or high risk of bias in most studies, inconsistency and imprecision.

The risk ratios for infectious complications (10 studies, 2804 participants) of each individual study ranged from 0.54 to 2.54. The quality of the evidence for this outcome was very low due to unclear or high risk of bias, inconsistency and imprecision.
We were not able to explain the causes of the observed heterogeneity using subgroup and sensitivity analyses or meta‐regression.

Authors’ conclusions:  The included studies had substantial clinical heterogeneity. We found very low‐quality evidence about the effects of prescribed hypocaloric nutrition support on mortality in hospital, in the ICU and at 30 days, as well as in length of hospital and ICU stay, infectious complications and the length of mechanical ventilation. For these outcomes there is uncertainty about the effects of prescribed hypocaloric nutrition, since the range of estimates includes both appreciable benefits and harms.

Given these limitations, results must be interpreted with caution in the clinical field, considering the unclear balance of the risks and harms of this intervention. Future research addressing the clinical heterogeneity of participants and interventions, study limitations and sample size could clarify the effects of this intervention.


Critical Care Reviews Newsletter 361 11th November 2018

Critical Care Reviews Newsletter, bringing you the best critical care research and open access articles from across the medical literature over the past seven days.  This week’s newsletter includes randomised controlled trials such as “Ketamine Infusion for Pain Control in Adult Patients with Multiple Rib Fractures”, systematic reviews including “Safety and efficacy of iron therapy on reducing red blood cell transfusion requirements and treating anaemia in critically ill adults” and observational studies such as “Prospective assessment of the feasibility of a trial of low tidal volume ventilation for patients with acute respiratory failure”
The full text of the newsletter is available via this link.

Energy-Dense versus Routine Enteral Nutrition in the Critically Ill

The article was published by the Target Investigators for the ANZICS Clinical Trails Group in the New England Journal of Medicine in November 2018

Background:  The effect of delivering nutrition at different calorie levels during critical illness is uncertain, and patients typically receive less than the recommended amount.

Methods:  We conducted a multicenter, double-blind, randomized trial, involving adults undergoing mechanical ventilation in 46 Australian and New Zealand intensive care units (ICUs), to evaluate energy-dense (1.5 kcal per milliliter) as compared with routine (1.0 kcal per milliliter) enteral nutrition at a dose of 1 ml per kilogram of ideal body weight per hour, commencing at or within 12 hours of the initiation of nutrition support and continuing for up to 28 days while the patient was in the ICU. The primary outcome was all-cause mortality within 90 days.

Results:  There were 3957 patients included in the modified intention-to-treat analysis (1971 in the 1.5-kcal group and 1986 in the 1.0-kcal group). The volume of enteral nutrition delivered during the trial was similar in the two groups; however, patients in the 1.5-kcal group received a mean (±SD) of 1863±478 kcal per day as compared with 1262±313 kcal per day in the 1.0-kcal group (mean difference, 601 kcal per day; 95% confidence interval [CI], 576 to 626). By day 90, a total of 523 of 1948 patients (26.8%) in the 1.5-kcal group and 505 of 1966 patients (25.7%) in the 1.0-kcal group had died (relative risk, 1.05; 95% CI, 0.94 to 1.16; P=0.41). The results were similar in seven predefined subgroups. Higher calorie delivery did not affect survival time, receipt of organ support, number of days alive and out of the ICU and hospital or free of organ support, or the incidence of infective complications or adverse events.

Conclusions:  In patients undergoing mechanical ventilation, the rate of survival at 90 days associated with the use of an energy-dense formulation for enteral delivery of nutrition was not higher than that with routine enteral nutrition.

The printed copy of the New England Journal of Medicine is available in the Health Care Library on D Level of Rotherham Hospital.

Effects of a multifaceted intervention QI program to improve ICU performance

This research by Ersson and colleagues was published in “BMC Health Services Research” in November 2018.
Background:  To benefit from the increasing clinical evidence, organisational changes have been among the main drivers behind the reduction of ICU mortality during the last decade. Increasing demand, costs and complexity, amplifies the need for optimisation of clinical processes and resource utilisation. Thus, multidisciplinary teamwork and critical care processes needs to be adapted to profit from increased availability of human skill and technical resources in a cost-effective manner. Inadequate clinical performance and outcome data compelled us to design a quality improvement project to address current work processes and competence utilisation.
Methods:  During revision period, clinical processes, professional performance and clinical competence were targeted using “scientific production management methodology” approach. As part of the project, an intensivist training program was instituted, and full time intensivist coverage was obtained in the process of creating multi-professional teams, composed of certified intensivists, critical care nurses, assistant nurses, physiotherapists and social counsellors. The use of staff resources and clinical work-processes were optimised in accordance with the outcome of a “value stream mapping”. In this process, efforts to enhance the personal dynamics and performance within the teams were paramount. Clinical and economic outcome data were analysed during a seven year follow up period.
Results:  Consecutive reduced overall ICU (24%) and long-term (600 days) mortality. The effect on ICU mortality was especially pronounced in the subgroup of patients > 65 years (30%) • Consecutive reduced length of stay (43%, septic patients) and time on ventilator (for septic patients and patients > 65 years of age (23 resp.52%). • Substantial increase in life years gained (13,140 life years) as well as quality-adjusted life-years (9593 QALY: s) over the study period. • High cost-effectiveness as ICU costs were reduced while patient outcomes were improved. Disregarding the cost reduction in ICU, the intervention is highly cost effective with cost- effectiveness ratios of (75€/QALY) and (55€ / life year).
Conclusions: We have shown favourable results of a QI project aiming to improve the clinical performance and quality through the development of multi-professional interaction, teamwork and systematic revisions of work processes. The economic evaluation shows that the intervention is highly cost-effective and potentially dominating.
The full text of this article is freely available via this link.

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

This Cochrane Systematic Review by Warttig and colleagues was published in June 2018.  The full text of the systematic review is available via this link.
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 syndrcochrane-57-1ome (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,, 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.

Incidence and risk factors of incontinence-associated dermatitis among patients in the intensive care unit

This research by Wang and colleagues was published in the November 2018 issue of the Journal of Clinical Nursing.
Objective:  To investigate the incidence of incontinence-associated dermatitis (IAD) among patients in the intensive care unit (ICU) and to identify potential risk factors to establish a reference for clinical nursing work.
Background:  Patients in the ICU are susceptible to IAD. IAD is painful, reduces the patient’s quality of life and adds to the workload of clinical medical staff. However, risk factors associated with IAD may differ between countries and healthcare settings.
Design:  Prospective cohort study.
Methods: From November 2016 to November 2017, a prospective cohort study was conducted among 109 patients in 3 Class 3, Grade A hospitals (comprising 9 ICUs in total) in Beijing. The Incontinence-associated Dermatitis and Its Severity (IADS) instrument in Chinese was applied to assess IAD.   Univariate and multivariate logistic regression analyses were performed to identify risk factors for IAD.
Results:  The study population had 29 community-acquired and 80 nosocomial infections, and 26 (incidence: 23.9%) of these had IAD. On univariate analysis, a significant difference was observed between patients with and without IAD with respect to the following indices: Barthel index, Braden scale score, Nutritional Risk Screening 2002 (NRS2002) score, serum albumin level, occurrence of infection, faecal incontinence, frequency of faecal incontinence, stool property and double (faecal and urinary) incontinence and perineal assessment tool (PAT) score (p < 0.05). Multivariate logistic regression analysis showed that three factors entered the regression equation-that is, the Braden Scale Score, serum albumin level and double incontinence. Of these, the Braden Scale Score and serum albumin level were protective factors for IAD. Thus, the higher the Braden Scale Score, the lower the risk of IAD (OR = 0.678, 95% confidence interval [CI] = 0.494-0.931); a higher level of serum albumin implies a lower risk of IAD, provided it is within the normal range (OR = 0.884, 95%CI = 0.797-0.981). Double incontinence was an independent risk factor for IAD (OR = 10.512, 95% CI = 2.492-44.342).
Conclusion:  A higher morbidity of IAD is seen in the ICU. Specific preventive and nursing measures are required to maintain the skin integrity of critically ill patients in daily nursing practice to improve patient quality of life and the quality of nursing care.
Relevance to Clinical Practice:  Incontinence-associated dermatitis is characterised by inflammation and tissue damage due to prolonged/repeated exposure to urine and/or stool. Not every patient with urine and/or stool incontinence develops IAD. Medical staff can use research-based evidence to identify ICU patients at risk of IAD to reduce morbidity and improve health outcomes.
To access the full text of this article via the journal’s homepage you require a personal subscription to the journal.  Some articles may be available freely without a password.  Library members can order individual articles via the Rotherham NHS Foundation Trust Library and Knowledge Service using the article requests online via this link.

Intensive care doctors’ preferences for arterial oxygen tension levels in mechanically ventilated patients

This research by Schjørring and colleagues was published in Acta Anaesthesiologica Scandinavica in November 2018.
Background:  Oxygen is liberally administered in intensive care units (ICUs). Nevertheless, ICU doctors’ preferences for supplementing oxygen are inadequately described. The aim was to identify ICU doctors’ preferences for arterial oxygenation levels in mechanically ventilated adult ICU patients.
Methods:  In April to August 2016, an online multiple-choice 17-part-questionnaire was distributed to 1080 ICU doctors in seven Northern European countries. Repeated reminder e-mails were sent. The study ended in October 2016.
Results:  The response rate was 63%. When evaluating oxygenation 52% of respondents rated arterial oxygen tension (PaO2 ) the most important parameter; 24% a combination of PaO2 and arterial oxygen saturation (SaO2 ); and 23% preferred SaO2 . Increasing, decreasing or not changing a default fraction of inspired oxygen of 0.50 showed preferences for a PaO2 around 8 kPa in patients with chronic obstructive pulmonary disease, a PaO2 around 10 kPa in patients with healthy lungs, acute respiratory distress syndrome or sepsis, and a PaO2 around 12 kPa in patients with cardiac or cerebral ischaemia. Eighty per cent would accept a PaO2 of 8 kPa or lower and 77% would accept a PaO2 of 12 kPa or higher in a clinical trial of oxygenation targets.
Conclusion:  Intensive care unit doctors preferred PaO2 to SaO2 in monitoring oxygen treatment when peripheral oxygen saturation was not included in the question. The identification of PaO2 as the preferred target and the thorough clarification of preferences are important when ascertaining optimal oxygenation targets. In particular when designing future clinical trials of higher vs lower oxygenation targets in ICU patients.
To access the full text of this article via the journal’s homepage you require a personal subscription to the journal.  Some articles may be available freely without a password.  Library members can order individual articles via the Rotherham NHS Foundation Trust Library and Knowledge Service using the article requests online via this link.