Defining Pediatric Chronic Critical Illness: A Scoping Review.

OBJECTIVES: Children with chronic critical illness (CCI) are hypothesized to be a high-risk patient population with persistent multiple organ dysfunction and functional morbidities resulting in recurrent or prolonged critical care; however, it is unclear how CCI should be defined. The aim of this scoping review was to evaluate the existing literature for case definitions of pediatric CCI and case definitions of prolonged PICU admission and to explore the methodologies used to derive these definitions. DATA SOURCES: Four electronic databases (Ovid Medline, Embase, CINAHL, and Web of Science) from inception to March 3, 2021. STUDY SELECTION: We included studies that provided a specific case definition for CCI or prolonged PICU admission. Crowdsourcing was used to screen citations independently and in duplicate. A machine-learning algorithm was developed and validated using 6,284 citations assessed in duplicate by trained crowd reviewers. A hybrid of crowdsourcing and machine-learning methods was used to complete the remaining citation screening. DATA EXTRACTION: We extracted details of case definitions, study demographics, participant characteristics, and outcomes assessed. DATA SYNTHESIS: Sixty-seven studies were included. Twelve studies (18%) provided a definition for CCI that included concepts of PICU length of stay (n = 12), medical complexity or chronic conditions (n = 9), recurrent admissions (n = 9), technology dependence (n = 5), and uncertain prognosis (n = 1). Definitions were commonly referenced from another source (n = 6) or opinion-based (n = 5). The remaining 55 studies (82%) provided a definition for prolonged PICU admission, most frequently greater than or equal to 14 (n = 11) or greater than or equal to 28 days (n = 10). Most of these definitions were derived by investigator opinion (n = 24) or statistical method (n = 18). CONCLUSIONS: Pediatric CCI has been variably defined with regard to the concepts of patient complexity and chronicity of critical illness. A consensus definition is needed to advance this emerging and important area of pediatric critical care research.

Midwifery research in areas of deprivation and need: the MeRIDiAN project.

Background: Areas with high levels of deprivation often have the lowest numbers of research participation. In January 2020, a maternity research service was established at a UK National Health Service (NHS) Trust incorporating a project monitoring equity of access to pregnant people from areas of deprivation and need. Aims: The aim is to monitor maternity research opportunities for pregnant people in areas of deprivation and need. Method: A collaborative working group was established. Using the Index of Multiple Deprivation levels (IMD) levels; 1-4 were considered 'areas in need'. Data were collected over a 12-month period from January 2020. Results: Fifty-four pregnant people (3.1%), out of 1762 who delivered during 2020, were recruited to one of three research studies ('Big Baby', 'POOL' and 'PAN-COVID'). The majority of pregnant people (65.9%) who delivered a baby were in IMD levels 1-4. Recruitment within IMD levels 1-4: 'PAN-COVID' at 86.7%, followed by 'Big Baby' with 77.3% and 'POOL' at 70.6%. COVID-19 pandemic presented challenges which impacted research delivery, including availability of research studies. Conclusion: This project was founded due to concerns that pregnant people from areas of need would be under-represented in research. We have found that this has not occurred. Recommendations are being put in place to ensure equity of access for all.

Extending the description of the clinical research nursing workforce.

Background: The role of Clinical Research Nurses across the globe has not been evaluated to identify similarities or differences among specific activities. Aims: This study's aims were to determine differences in Clinical Research Nurses most frequently performed activities, if these activities are reflective of those previously described in the literature, and job titles Clinical Research Nurses use to self-identify. Methods: An online cross-sectional survey distributed via snowball sampling through email, social media, and research nurses' networks included questions on frequency of activities performed and information related to job titles. Pearson's chi-square test is analyzed for associations between the groups. Results: Respondents returned 252 questionnaires, 233 were eligible for analysis. Research nurse activities performed internationally showed both similarities and differences. Any between country comparisons will be limited to the United States and the United Kingdom. The three most common tasks reported were recruitment 120 (51.5%), monitoring the research participant for potential adverse events 187 (80.2%) and providing nursing leadership within the interdisciplinary team 169 (72.5%). Conclusion: Considering the context and range of activities of the original Clinical Research Nursing Domain of Practice, broadening the framework to include the leadership domain will better serve as a foundation for the specialty practice.

Health-Related Quality of Life in Pediatric Cardiac Patients After Extracorporeal Life Support.

Extracorporeal Life Support (ECLS) is often considered successful if the child leaves intensive care alive. For the child and family, a major concern is quality of life. Aim of this study is to compare health-related quality of life scores of children following cardiac ECLS to a healthy control group. Cross-sectional prospective study using Pediatric Quality of Life Inventory 4.0 Generic Core Scale questionnaire. Population included consecutive children between two and sixteen years of age who underwent cardiac ECLS from 2005 to 2016 and their parents. Each age groups' mean and standard deviation was analyzed individually with minimal clinically important difference calculated. We then compared the scores to a healthy population group. Cronbach's alpha for reliability was calculated and linear regression assessed for relationships between demographics and quality of life scores. Forty-one (60%) families responded. The ECLS had significantly (statistically and clinically) lower health-related quality of life scores in every domain when compared to the healthy cohort. The lowest mean total score was school functioning for both children (59.79 vs 81.31, p < 0.01) and parents (59.01 vs 78.27, p < 0.01). Parents had excellent reliability (α = 0.93, 0.95 & 0.90) compared to children with reliability improving with increasing age in children. Improvements in the management of pediatric patients following ECLS are required to improve their health-related quality of life. Further research is warranted to explore the physical and psychological effects of cardiac ECLS on pediatric survivors to establish individual healthcare needs and optimize health-related quality of life.

Cohort study to determine the risk of pressure ulcers and developing a care bundle within a paediatric intensive care unit setting.

OBJECTIVE: Determine the incidence and risk factors for pressure ulcers in a paediatric intensive care unit. Use the information gathered to develop preventive pressure ulcer care bundles. RESEARCH METHODOLOGY: Prospective cohort study using Braden Q Scale for Predicting Pressure Sore Risk and European Pressure Ulcer Advisory Panel Pressure Ulcer Staging tool. SETTING: General paediatric intensive care unit in a tertiary level hospital between May and October 2017. RESULTS: Seventy-seven children were recruited. Most children were male (n = 42, 54.5%) and all nine children (11.7%) that developed a pressure ulcer were male. The main risk factor for developing a pressure ulcer was lack of physical activity. None of the children assessed as high or severe risk developed a pressure ulcer. Eight (89%) pressure ulcers were assessed as grade one. Seven pressure ulcers (77.8%) were on the facial and scalp area and all seven children were receiving airway support at the time the pressure ulcers developed. CONCLUSION: Incidence of pressure ulcers was 11.7%, with the facial and scalp area the most common anatomical areas affected. Medical devices appeared to be the prime causative factor. Based on our data we have modified and launched the SSKIN care bundle for the paediatric intensive care unit setting.

Associations between maternal lifestyle factors and neonatal body composition in the Screening for Pregnancy Endpoints (Cork) cohort study.

Background: Neonatal body composition likely mediates fetal influences on life long chronic disease risk. A better understanding of how maternal lifestyle is related to newborn body composition could thus inform intervention efforts. Methods: Using Cork participant data (n = 1754) from the Screening for Pregnancy Endpoints (SCOPE) cohort study [ECM5(10)05/02/08], we estimated how pre-pregnancy body size, gestational weight gain, exercise, alcohol, smoking and diet were related to neonatal fat and fat-free mass, as well as length and gestational age at birth, using quantile regression. Maternal factors were measured by a trained research midwife at 15 gestational weeks, in addition to a 3rd trimester weight measurement used to calculate weight gain. Infant body composition was measured using air-displacement plethysmography. Results: Healthy (versus excess) gestational weight gain was associated with lower median fat-free mass [-112 g, 95% confidence interval (CI): -47 to -176) and fat mass (-33 g, 95% CI: -1 to -65) in the offspring; and a 103 g decrease in the 95th centile of fat mass (95% CI: -33 to -174). Maternal normal weight status (versus obesity) was associated with lower median fat mass (-48 g, 95% CI: -12 to -84). At the highest centiles, fat mass was lower among infants of women who engaged in frequent moderate-intensity exercise early in the pregnancy (-92 g at the 95th centile, 95% CI: -168 to -16). Lastly, women who never smoked tended to have longer babies with more fat mass and fat-free mass. No other lifestyle factors were strongly related to infant body composition. Conclusions: These results suggest that supporting healthy maternal lifestyles could reduce the risk of excess fat accumulation in the offspring, without adversely affecting fat-free mass development, length or gestational age.

Methods of milk expression for lactating women.

BACKGROUND: Breastfeeding is important, however not all infants can feed at the breast and methods of expressing milk need evaluation. OBJECTIVES: To assess acceptability, effectiveness, safety, effect on milk composition, contamination and costs of methods of milk expression. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (21 March 2016), handsearched relevant journals and conference proceedings, and contacted experts in the field to seek additional published or unpublished studies. We also examined reference lists of all relevant retrieved papers. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing methods at any time after birth. DATA COLLECTION AND ANALYSIS: Three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. MAIN RESULTS: This updated review includes 41 trials involving 2293 participants, with 22 trials involving 1339 participants contributing data for analysis. Twenty-six of the trials referred to mothers of infants in neonatal units (n = 1547) and 14 to mothers of healthy infants at home (n = 730), with one trial containing mothers of both neonatal and healthy older infants (n = 16). Eleven trials compared one or more types of pump versus hand expression and 14 studies compared one type of pump versus another type of pump, with three of these studies comparing both hand expression and pump types. Twenty studies compared a specific protocol or adjunct behaviour including sequential versus simultaneous pumping protocols, pumping frequency, provision of an education and support intervention, relaxation, breast massage, combining hand expression with pumping and a breast cleansing protocol.Due to heterogeneity in participants, interventions, and outcomes measured or reported, we were unable to pool findings for most of the specified outcomes. It was not possible therefore to produce a 'Summary of findings' table in this update. Most of the included results were derived from single studies. Trials took place in 14 countries under a variety of circumstances and were published from 1982 to 2015. Sixteen of the 30 trials that evaluated pumps or products had support from the manufacturers. The risk of bias of the included studies was variable. Primary outcomesOnly one of the 17 studies examining maternal satisfaction/acceptability with the method or adjunct behaviour provided data suitable for analysis. In this study, self-efficacy was assessed by asking mothers if they agreed or disagreed with the following statement: 'I don't want anyone to see me (hand expressing/pumping)'. The study found that mothers who were using the electric pump were more likely to agree with the statement compared to mothers hand expressing, (mean difference (MD) 0.70, 95% confidence interval (CI) 0.15 to 1.25; P = 0.01, participants = 68). Mothers who were hand expressing reported that the instructions for expression were clearer compared to the electric pump, (MD -0.40, 95% CI -0.75 to -0.05; P = 0.02, participants = 68). Descriptive reporting of satisfaction in the other studies varied in the measures used, did not indicate a clear preference for one pump type, although there was satisfaction with some relaxation and support interventions.We found no clinically significant differences between methods related to contamination of the milk that compared any type of pump to hand expression (risk ratio (RR) 1.13, 95% CI 0.79 to 1.61; P = 0.51, participants = 28), manual pump compared to hand expression, (MD 0.20, 95% CI -0.18 to 0.58; P = 0.30, participants = 142) a large electric pump compared to hand expression (MD 0.10, 95% CI -0.29 to 0.49; P = 0.61, participants = 123), or a large electric pump compared to a manual pump (MD -0.10, 95% CI -0.46 to 0.26; P = 0.59, participants = 141).The level of maternal breast or nipple pain or damage was similar in comparisons of a large electric pump to hand expression (MD 0.02, 95% CI -0.67 to 0.71; P = 0.96, participants = 68). A study comparing a manual and large electric pump, reported sore nipples in 7% for both groups and engorgement in 4% using a manual pump versus 6% using an electric pump; and in one study no nipple damage was reported in the hand-expression group, and one case of nipple damage in each of the manual pump and the large electric pump groups.One study examined adverse effects on infants, however as the infants did not all receive their mothers' expressed milk, we have not included the results. Secondary outcomesThe quantity of expressed milk obtained was increased, in some studies by a clinically significant amount, in interventions involving relaxation, music, warmth, massage, initiation of pumping, increased frequency of pumping and suitable breast shield size. Support programmes and simultaneous compared to sequential pumping did not show a difference in milk obtained. No pump consistently increased the milk volume obtained significantly.In relation to nutrient quality, hand expression or a large electric pump were found to provide higher protein than a manual pump, and hand expression provided higher sodium and lower potassium compared to a large electric pump or a manual pump. Fat content was higher with breast massage when pumping; no evidence of difference was found for energy content between methods.No consistent effect was found related to prolactin change or effect on oxytocin release with pump type or method. Economic aspects were not reported. AUTHORS' CONCLUSIONS: The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low-cost interventions including initiation of milk expression sooner after birth when not feeding at the breast, relaxation, massage, warming the breasts, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Variation in nutrient content across methods may be relevant to some infants. Small sample sizes, large standard deviations, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings. Independently funded research is needed for more trials on hand expression, relaxation and other techniques that do not have a commercial potential.

Early additional food and fluids for healthy breastfed full-term infants.

BACKGROUND: Health organisations recommend exclusive breastfeeding for six months. However, the addition of other fluids or foods before six months is common in many countries. Recently, research has suggested that introducing solid food at around four months of age while the baby continues to breastfeed is more protective against developing food allergies compared to exclusive breastfeeding for six months. Other studies have shown that the risks associated with non-exclusive breastfeeding are dependent on the type of additional food or fluid given. Given this background we felt it was important to update the previous version of this review to incorporate the latest findings from studies examining exclusive compared to non-exclusive breastfeeding. OBJECTIVES: To assess the benefits and harms of additional food or fluid for full-term healthy breastfeeding infants and to examine the timing and type of additional food or fluid. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 March 2016) and reference lists of all relevant retrieved papers. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials in infants under six months of age comparing exclusive breastfeeding versus breastfeeding with any additional food or fluids. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. Two review authors assessed the quality of the evidence using the GRADE approach. MAIN RESULTS: We included 11 trials (2542 randomised infants/mothers). Nine trials (2226 analysed) provided data on outcomes of interest to this review. The variation in outcome measures and time points made it difficult to pool results from trials. Data could only be combined in a meta-analysis for one primary (breastfeeding duration) and one secondary (weight change) outcome. None of the trials reported on physiological jaundice. Infant mortality was only reported in one trial.For the majority of older trials, the description of study methods was inadequate to assess the risk of bias. Most studies that we could assess showed a high risk of other biases and over half were at high risk of selection bias.Providing breastfeeding infants with artifical milk, compared to exclusive breastfeeding, did not affect rates of breastfeeding at hospital discharge (risk ratio (RR) 1.02, 95% confidence interval (CI) 0.97 to 1.08; one trial, 100 infants; low-quality evidence). At three months, breastfeeding infants who were provided with artificial milk had higher rates of any breastfeeding compared to exclusively breastfeeding infants (RR 1.21, 95% CI 1.05 to 1.41; two trials, 137 infants; low-quality evidence). Infants who were given artifical milk in the first few days after birth before breastfeeding, had less "obvious or probable symptoms" of allergy compared to exclusively breastfeeding infants (RR 0.56, 95% CI 0.35 to 0.91; one trial, 207 infants; very low-quality evidence). No difference was found in maternal confidence when comparing non-exclusive breastfeeding infants who were provided with artificial milk with exclusive breastfeeding infants (mean difference (MD) 0.10, 95% CI -0.34 to 0.54; one study, 39 infants; low-quality evidence). Rates of breastfeeding were lower in the non-exclusive breastfeeding group compared to the exclusive breastfeeding group at four, eight, 12 (RR 0.68, 95% CI 0.53 to 0.87; one trial, 170 infants; low-quality evidence), 16 and 20 weeks.The addition of glucose water resulted in fewer episodes of hypoglycaemia (below 2.2 mmol/L) compared to the exclusive breastfeeding group, reported at 12 hours (RR 0.07, 95% CI 0.00 to 1.20; one trial, 170 infants; very low-quality evidence), but no significant difference at 24 hours (RR 1.57, 95% CI 0.27 to 9.17; one trial, 170 infants; very low-quality evidence). Weight loss was lower for infants who received additional glucose water (one trial, 170 infants) at six, 12, 24 and 48 hours of life (MD -32.50 g, 95% CI -52.09 to -12.91; low-quality evidence) compared to the exclusively breastfeeding infants but no difference between groups was observed at 72 hours of life (MD 3.00 g, 95% CI -20.83 to 26.83; very low-quality evidence). In another trial with the water and glucose water arms combined (one trial, 47 infants), we found no significant difference in weight loss between the additional fluid group and the exclusively breastfeeding group on either day three or day five (MD -1.03%, 95% CI -2.24 to 0.18; very low-quality evidence) and (MD -0.20%, 95% CI -0.86 to 0.46; very low-quality evidence).Infant mortality was reported in one trial with no deaths occurring in either group (1162 infants). The early introduction of potentially allergenic foods, compared to exclusively breastfeeding, did not reduce the risk of "food allergy" to one or more of these foods between one to three years of age (RR 0.80, 95% CI 0.51 to 1.25; 1162 children), visible eczema at 12 months stratified by visible eczema at enrolment (RR 0.86, 95% CI 0.51 to 1.44; 284 children), or food protein-induced enterocolitis syndrome reactions (RR 2.00, 95% CI 0.18 to 22.04; 1303 children) (all moderate-quality evidence). Breastfeeding infants receiving additional foods from four months showed no difference in infant weight gain (g) from 16 to 26 weeks compared to exclusive breastfeeding to six months (MD -39.48, 95% CI -128.43 to 49.48; two trials, 260 children; low-quality evidence) or weight z-scores (MD -0.01, 95% CI -0.15 to 0.13; one trial, 100 children; moderate-quality evidence). AUTHORS' CONCLUSIONS: We found no evidence of benefit to newborn infants on the duration of breastfeeding from the brief use of additional water or glucose water. The quality of the evidence on formula supplementation was insufficient to suggest a change in practice away from exclusive breastfeeding. For infants at four to six months, we found no evidence of benefit from additional foods nor any risks related to morbidity or weight change. The majority of studies showed high risk of other bias and most outcomes were based on low-quality evidence which meant that we were unable to fully assess the benefits or harms of supplementation or to determine the impact from timing and type of supplementation. We found no evidence to disagree with the current international recommendation that healthy infants exclusively breastfeed for the first six months.

Methods of milk expression for lactating women.

BACKGROUND: This is an update of a 2008 Cochrane review. Breastfeeding is important. However, not all infants can feed at the breast and methods of expressing milk need evaluation. OBJECTIVES: To assess acceptability, effectiveness, safety, effect on milk composition, contamination and cost implications of methods of milk expression. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2014), CINAHL (1982 to March 2014), conference proceedings, secondary references and contacted researchers. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing methods at any time after birth. DATA COLLECTION AND ANALYSIS: Three authors independently assessed trials, extracted data and assessed risk of bias. MAIN RESULTS: This updated review includes 34 studies involving 1998 participants, with 17 trials involving 961 participants providing data for analysis. Eight studies compared one or more types of pump versus hand expression and 14 studies compared one type of pump versus another type of pump, with three of these studies comparing both hand expression and multiple pump types. Fifteen studies compared a specific protocol or adjunct behaviour including sequential versus simultaneous pumping protocols (five studies), pumping > 4 times per day versus < 3 times per day (one study), provision of a milk expression education and support intervention to mothers of preterm infants versus no provision (one study), provision of audio/visual relaxation to mothers of preterm infants versus no specific relaxation (two studies), commencing pumping within one hour of delivery versus between one to six hours (one study), breast massage before or during pumping versus no massage (two studies, of which one also tested a second behaviour), therapeutic touch versus none (one study), warming breasts before pumping versus not warming breasts (one study), combining hand expression with pumping versus pumping alone (one study) and a breast cleansing protocol versus no protocol (one study).There were insufficient comparable data on outcomes to undertake meta-analysis and data reported relates to evidence from single studies.Only one of the 17 studies examining maternal satisfaction/acceptability provided data in a way that could be analysed, reporting that mothers assigned to the pumping group had more agreement with the statement 'I don't want anyone to see me pumping' than mothers in the hand expression group and the statement 'I don't want anyone to see me hand expressing' (n = 68, mean difference (MD) -0.70, 95% confidence interval (CI) -1.25 to -0.15, P = 0.01), and that mothers found instructions for hand expression were clearer than for pumping (n = 68, MD 0.40, 95% CI 0.05 to 0.75, P = 0.02). No evidence of a difference was found between methods related to adverse effects of milk contamination (one study, n = 28, risk ratio (RR) 0.89, 95% CI 0.62 to 1.27, P = 0.51), (one study, n = 142 milk samples, MD 0.20, 95% CI -0.18 to 0.58, P = 0.30), (one study, n = 123 milk samples, MD 0.10, 95% CI -0.29 to 0.49, P = 0.61), (one study, n = 141 milk samples, MD -0.10, 95% CI -0.46 to 0.26, P = 0.59 ); or level of maternal breast or nipple pain or damage (one study, n = 68, MD 0.02, 95% CI -0.67 to 0.71, P = 0.96).For the secondary outcomes, greater volume was obtained when mothers with infants in a neonatal unit were provided with a relaxation tape or music-listening interventions to use while pumping, when the breasts was warmed before pumping or massaged while pumping.Initiation of milk pumping within 60 minutes of birth of a very low birthweight infant obtained higher mean milk quantity in the first week than the group who initiated pumping later. No evidence of difference in volume was found with simultaneous or sequential pumping or between pumps studied. Differences between methods was found for sodium, potassium, protein and fat constituents; no evidence of difference was found for energy content.No consistent effect was found related to prolactin change or effect on oxytocin release with pump type or method. Economic aspects were not reported.Most studies were classified as unclear or low risk of bias. Most studies did not provide any information regarding blinding of outcome assessment. Fifteen of the 25 studies that evaluated pumps or products had support from the manufacturers. AUTHORS' CONCLUSIONS: The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low-cost interventions including early initiation when not feeding at the breast, listening to relaxation music, massage and warming of the breasts, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Small sample sizes, large standard deviations, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings.

Methods of milk expression for lactating women.

BACKGROUND: This is an update of a 2008 Cochrane review. Breastfeeding is important. However, not all infants can feed at the breast and methods of expressing milk need evaluation. OBJECTIVES: To assess acceptability, effectiveness, safety, effect on composition, contamination and cost implications of methods of milk expression. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 January 2011), CINAHL (1982 to January 2011), conference proceedings, secondary references and contacted researchers. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing methods at any time after birth, and crossover trials commencing at least 28 days after birth. DATA COLLECTION AND ANALYSIS: Three authors independently assessed trials, extracted data and assessed risk of bias. Data were checked for accuracy. MAIN RESULTS: We included 23 studies with 10 studies (632 mothers) providing data for analysis.Mothers provided with a relaxation tape produced more milk than mothers who were not (mean difference (MD) 34.70 ml/single expression, 95% confidence interval (CI) 9.51 to 59.89, P = 0.007). A lower milk volume over six days was reported when comparing hand expression to the electric pump (standardised mean difference (SMD) -1.00 ml, 95% CI -1.64 to -0.36, P = 0.002); other studies of the same pump using different measures did not find a significant difference (12 to 36 hours postpartum SMD -0.38 cc, 95% CI -0.86 to 0.10, P = 0.12); day five postpartum SMD -0.62 ml/day, 95% CI -1.43 to 0.19, P = 0.13). No evidence of difference in volume was found with simultaneous or sequential pumping, or between manual and electric pumps studied. One study reported a higher sodium concentration in hand expressed milk compared to a manual pump (SMD 0.59 mmol/L, 95% CI 0.22 to 0.96, P = 0.002) and to an electric pump (SMD 0.70 mmol/L, 95% CI 0.32 to 1.09, P = 0.0003), and lower potassium concentration compared to a manual pump (MD -0.37 mmol/L, 95% CI 0.00 to 0.73, P = 0.05) or to an electric pump (SMD -0.32 mmol/L, 95% CI -0.69 to 0.06, P = 0.10). No evidence of difference was found for energy content, milk contamination or adverse effects. Reports of maternal views were not comparable. Economic aspects were not reported.   AUTHORS' CONCLUSIONS: The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low cost interventions including early initiation when not feeding at the breast, relaxation, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Small sample sizes, large standard deviations, small number of studies reviewed, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings.