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Common variable immunodeficiency (CVID) is the most common primary immune deficiency characterized by impaired production of specific immunoglobulin. The clinical manifestations are heterogeneous including acquisition of recurrent bacterial infections after a period of wellness, lymphoproliferation, autoimmunity, pulmonary disease, liver disease, enteropathy, granulomas, and an increased risk of malignancy. The etiology of CVID is largely unknown, with a considerable number of patients having an underlying genetic defect causing immune dysregulation. The antibody deficiency found in CVID is treated with lifelong immunoglobulin therapy, which is preventative of the majority of infections when given regularly., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Intrauterine devices (IUDs) are highly effective contraception. IUDs inserted directly following delivery provide immediate birth control and may decrease unintended pregnancies, including short-interval pregnancies, thereby mitigating health risks and associated economic burden., Methods: This systematic literature review included published global data on the utilisation, effectiveness, and safety of postpartum intrauterine devices (PPIUDs) of any type. English language articles indexed in MEDLINE, Embase, and Cochrane from January 2010-October 2021 were included., Results: 133 articles met the inclusion criteria (46% interventional studies; 54% observational; n=87 from lower-income countries; n=46 from higher-income countries). PPIUD use was low in higher-income countries (6/10 000 US deliveries in 2013-2016) and varied widely in lower-income countries (2%-46%). Across both higher- and lower-income countries, in most studies (79%), >80% of women with PPIUDs had an IUD in place by 3 months; at 6 and 12 months, 76% and 54% of included studies reported that >80% of women had an IUD in place; reason for discontinuation was infrequently reported. Pregnancies were rare (96 pregnancies across 12 191 women from 37 studies reporting data) and were generally unrelated to device failure, but rather occurred in women no longer using a PPIUD. Expulsions occurred mainly in the early outpatient period and ranged widely (within 3 months: 0-41%). Abnormal bleeding, infections, or perforations were rare., Conclusions: PPIUDs are safe and effective. Long-term follow-up data are limited. Future research elucidating reasons underlying lack of PPIUD use is warranted., Competing Interests: Competing interests: EG-E reports personal fees from Xcenda LLC, during the conduct of the study. JL reports personal fees, non-financial support and other from Bayer US LLC, outside the submitted work. KRB, YW, NW, and FP are all employees of Bayer, which manufactures IUDs among its portfolio of products., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Older adults are the least active population in the U.S. Low-income communities have fewer physical activity (PA) resources, contributing to less PA and increased chronic disease risk. This study assessed the effect of the multilevel, peer-led, Peer Empowerment Program 4 Physical Activity (PEP4PA) on moderate-to-vigorous PA (MVPA) and health outcomes, over 2 years of follow up., Methods: In a cluster-randomized controlled trial, 12 senior or community centers serving low-income older adults were assigned to a PA intervention (n = 6) or usual programming (n = 6) condition. PEP4PA included self-monitoring, health coaching, group walks, social support, and community advocacy to improve walking conditions. The primary outcome was daily minutes of MVPA (7-day accelerometer). Secondary outcomes included Perceived Quality of Life (PQoL), 6-Minute Walk Test (6-MWT), blood pressure (BP), and depressive symptoms at baseline, 6, 12, 18 and 24 months. Mixed effects regression models estimated the effects on outcomes between groups over time and included random effects for repeated measures and center clustering. Effect modification by sex and income status was assessed. We calculated the incremental cost per daily minute of MVPA gained in the intervention group relative to the control group to assess cost effectiveness., Results: We enrolled 476 older adults (50 + years). Participants were on average 71 years old, 76% female, 60% low income, and 38% identified as racial or ethnic minorities. Compared to the control group, intervention participants sustained roughly a 10 min/day increase in MVPA from baseline at all time points and increased mean PQoL scores from unsatisfied at baseline to satisfied at 12, 18 and 24 months. Males and higher-income groups had greater improvements in MVPA. No significant effects were observed for 6-MWT or depressive symptoms, and BP results were mixed. The incremental cost per minute MVPA gained per person was $0.25, $0.09, $0.06, and $0.05 at 6, 12, 18 and 24 months, respectively., Conclusions: PEP4PA achieved increases in MVPA and PQoL in low-income older adults, over 2 years of follow up. The peer-led, community-based intervention provides a sustainable and cost-effective model to improve health behaviors in underserved, aging populations., Trial Registration: ClinicalTrials.gov ( NCT02405325 ) March 20, 2015., (© 2022. The Author(s).)

Background: For women undergoing median sternotomy, especially those with a bra cup size C or larger, breast support can reduce pain, wound breakdown, and infection. This study addressed a gap in research, identifying the best bra after sternotomy in terms of patient satisfaction and wear compliance., Objectives: To evaluate larger-breasted women's satisfaction and compliance with wearing 3 commercially available front-closure bras-with a hook-loop closure (the hospital's standard of care), a zipper closure, or a hook-eye closure-after cardiac surgery., Methods: This study used a posttest-only, 3-group randomized controlled design. A convenience sample of participants were sized and randomly assigned a product that was placed immediately postoperatively. Participants agreed to wear the bra at least 20 h/d until the provider cleared them for less wear. At inpatient day 5 or discharge, and at the follow-up outpatient visit, subjects completed investigator-developed surveys. Data were analyzed from 60 participants by using the χ2 test and Kruskal-Wallis analysis of variance; also, patterns were identified within written comments., Results: Participants were most satisfied with the hook-eye front-closure product before (P = .05) and after (P = .02) discharge. Participants recommended the hook-eye and zipper products over the hook-loop bra (H = 8.39, P = .02). Wear compliance was strongest in the group wearing the hook-eye bra., Conclusions: The hook-eye closure product had the most satisfaction and greatest wear compliance, and it received the highest recommendation. A practice change was made to fit and place the hook-eye bra in the operating room immediately after surgery., (©2021 American Association of Critical-Care Nurses.)

The U.S. population over 65 years of age is increasing. Most older adults prefer to age in place, and technologies, including Internet of things (IoT), Ambient/Active Assisted Living (AAL) robots and other artificial intelligence (AI), can support independent living. However, a top-down design process creates mismatches between technologies and older adults' needs. A user-centered design approach was used to identify older adults' perspectives regarding AAL and AI technologies and gauge interest in participating in a co-design process. A survey was used to obtain demographic characteristics and assess privacy perspectives. A convenience sample of 31 retirement community residents participated in one of two 90-min focus group sessions. The semi-structured group interview solicited barriers and facilitators to technology adoption, privacy attitudes, and interest in project co-design participation to inform technology development. Focus group sessions were audiotaped and professionally transcribed. Transcripts were reviewed and coded to identify themes and patterns. Descriptive statistics were applied to the quantitative data. Identified barriers to technology use included low technology literacy, including lack of familiarity with terminology, and physical challenges, which can make adoption difficult. Facilitators included an eagerness to learn, interest in co-design, and a desire to understand and control their data. Most participants identified as privacy pragmatics and fundamentalists, indicating that privacy is important to older adults. At the same time, they also reported a willingness to contribute to the design of technologies that would facilitate aging independently. There is a need to increase technology literacy of older adults along with aging literacy of technologists.

Background: Older adults are the least active population group. Interventions in residential settings may support a multi-level approach to behavior change., Methods: In a cluster randomized control trial, 11 San Diego retirement communities were assigned to a physical activity (PA) intervention or a healthy aging attention control condition. Participants were 307 adults over 65 years old. The multilevel PA intervention was delivered with the assistance of peer leaders, who were trained older adult from the retirement communities. Intervention components included individual counseling & self-monitoring with pedometers, group education sessions, group walks, community advocacy and pedestrian community change projects. Intervention condition by time interactions were tested using generalized mixed effects regressions. The primary outcomes was accelerometer measured physical activity. Secondary outcomes were blood pressure and objectively measured physical functioning., Results: Over 70% of the sample were 80 years or older. PA significantly increased in the intervention condition (56 min of moderate-vigorous PA per week; 119 min of light PA) compared with the control condition and remained significantly higher across the 12 month study. Men and participants under 84 years old benefited most from the intervention. There was a significant decrease in systolic (p < .007) and diastolic (p < .02) blood pressure at 6 months. Physical functioning improved but the changes were not statistically significant., Conclusions: Intervention fidelity was high demonstrating feasibility. Changes in PA and blood pressure achieved were comparable to other studies with much younger participants. Men, in particular, avoided a year-long decline in PA., Trial Registration: clincialtrials.gov Identifier: NCT01155011 .

Background: As the US population ages, there is an increasing need for evidence based, peer-led physical activity programs, particularly in ethnically diverse, low income senior centers where access is limited., Methods/design: The Peer Empowerment Program 4 Physical Activity' (PEP4PA) is a hybrid Type II implementation-effectiveness trial that is a peer-led physical activity (PA) intervention based on the ecological model of behavior change. The initial phase is a cluster randomized control trial randomized to either a peer-led PA intervention or usual center programming. After 18 months, the intervention sites are further randomized to continued support or no support for another 6 months. This study will be conducted at twelve senior centers in San Diego County in low income, diverse communities. In the intervention sites, 24 peer health coaches and 408 adults, aged 50 years and older, are invited to participate. Peer health coaches receive training and support and utilize a tablet computer for delivery and tracking. There are several levels of intervention. Individual components include pedometers, step goals, counseling, and feedback charts. Interpersonal components include group walks, group sharing and health tips, and monthly celebrations. Community components include review of PA resources, walkability audit, sustainability plan, and streetscape improvements. The primary outcome of interest is intensity and location of PA minutes per day, measured every 6 months by wrist and hip accelerometers and GPS devices. Secondary outcomes include blood pressure, physical, cognitive, and emotional functioning. Implementation measures include appropriateness & acceptability (perceived and actual fit), adoption & penetration (reach), fidelity (quantity & quality of intervention delivered), acceptability (satisfaction), costs, and sustainability., Discussion: Using a peer led implementation strategy to deliver a multi-level community based PA program can enhance program adoption, implementation, and sustainment., Trial Registration: ClinicalTrials.gov, USA ( NCT02405325 ). Date of registration, March 20, 2015. This website also contains all items from the World Health Organization Trial Registration Data Set.

Background: Excessive sitting has been linked to poor health. It is unknown whether reducing total sitting time or increasing brief sit-to-stand transitions is more beneficial. We conducted a randomized pilot study to assess whether it is feasible for working and non-working older adults to reduce these two different behavioral targets., Methods: Thirty adults (15 workers and 15 non-workers) age 50-70 years were randomized to one of two conditions (a 2-hour reduction in daily sitting or accumulating 30 additional brief sit-to-stand transitions per day). Sitting time, standing time, sit-to-stand transitions and stepping were assessed by a thigh worn inclinometer (activPAL). Participants were assessed for 7 days at baseline and followed while the intervention was delivered (2 weeks). Mixed effects regression analyses adjusted for days within participants, device wear time, and employment status. Time by condition interactions were investigated., Results: Recruitment, assessments, and intervention delivery were feasible. The 'reduce sitting' group reduced their sitting by two hours, the 'increase sit-to-stand' group had no change in sitting time (p < .001). The sit-to-stand transition group increased their sit-to-stand transitions, the sitting group did not (p < .001)., Conclusions: This study was the first to demonstrate the feasibility and preliminary efficacy of specific sedentary behavioral goals., Trial Registration: clinicaltrials.gov NCT02544867.

Objectives: To describe the intervention protocol for the first multilevel ecological intervention for physical activity in retirement communities that addresses individual, interpersonal and community influences on behavior change., Design: A cluster randomized controlled trial design was employed with two study arms: a physical activity intervention and an attention control successful aging condition., Setting: Sixteen continuing care retirement communities in San Diego County., Participants: Three hundred twenty older adults, aged 65 years and older, are being recruited to participate in the trial. In addition, peer leaders are being recruited to lead some study activities, especially to sustain the intervention after study activities ceased., Intervention: Participants in the physical activity trial receive individual, interpersonal and community intervention components. The individual level components include pedometers, goal setting and individual phone counseling. The interpersonal level components include group education sessions and peer-led activities. The community level components include resource audits and enumeration, tailored walking maps, and community improvement projects. The successful aging group receives individual and group attention about successful aging topics., Measurements: The main outcome is light to moderate physical activity, measured objectively by accelerometry. Other objective outcomes included physical functioning, blood pressure, physical fitness, and cognitive functioning. Self report measures include depressive symptoms and health related quality of life., Results: The intervention is being delivered successfully in the communities and compliance rates are high., Conclusion: Ecological Models call for interventions that address multiple levels of the model. Previous studies have not included components at each level and retirement communities provide a model environment to demonstrate how to implement such an intervention., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: To assess the prevalence of motivation and behaviours relating to smoking cessation and attempts at harm minimization and the stability of these over a 1-year period; to identify demographic, social, behavioural and psychological predictors of attempts to stop smoking and the success of these attempts., Design: Face-to-face interviews were carried out with a national sample of UK smokers in April/May 1996 with follow-up 1 year later., Subjects: The original response rate was 61% (1478 of 1911 adult smokers), and of these 1012 were followed-up 1 year later (68% of those who were originally contactable)., Results: Thirty-one per cent of smokers reported making at least one quit attempt during the follow-up period and 17% made a quit attempt in the first 9 months of that period. Of these 29% were still not smoking at least 3 months later. Fifty-one per cent of smokers had tried to cut down in the year leading up to the first survey. There was a fair degree of consistency over time in individual smokers' desires and intentions to stop smoking across both surveys and in the incidence of quit attempts and attempts to cut down. Beliefs about the effects of smoking on future health and having a partner who disliked their smoking were positively associated with making a quit attempt at follow-up while reporting enjoying smoking at baseline was negatively associated with making a quit attempt at follow-up. Time to first cigarette of the day and age of starting smoking were positively associated with success of quit attempts., Conclusions: Motivation and behaviours relating to smoking cessation are prevalent and fairly stable over time. Different factors appear to be related to attempts to stop and the success of those attempts. Interventions to increase smoking cessation in the population should take account of this.

Objectives: Despite improvements in organ preservation, reperfusion injury remains a major source of morbidity and mortality after lung transplantation. This pilot study was designed to investigate the effects of controlled reperfusion after lung ischemia., Methods: Twenty adult pigs underwent 2 hours of warm lung ischemia by crossclamping the left bronchus and pulmonary artery. In five (group 1), the clamp was simply removed at the end of ischemia (uncontrolled reperfusion). The 15 other pigs underwent modified reperfusion using blood from the femoral artery to perfuse the lung through the pulmonary artery (pressure 40 to 50 mm Hg) for 10 minutes before removing the pulmonary artery clamp. In five (group 2), the blood was mixed with crystalloid, resulting in a substrate-enriched, hypocalcemic, hyperosmolar, alkaline solution. In five (group 3), the blood was circulated through a leukocyte-depleting filter, and the last five (group 4) underwent reperfusion with both a modified solution and white blood cell filter. Lung function was assessed 60 minutes after reperfusion, and biopsy specimens were taken., Results: Controlled reperfusion with both a white blood cell filter and modified solution (group 4) completely eliminated the reperfusion injury that occurred with uncontrolled reperfusion (group 1), resulting in complete preservation of compliance (98% +/- 1% vs 77% +/- 1%; p < 0.001, and arterial/alveolar ratio (97% +/- 2% vs 27% +/- 2%; p < 0.001); no increase in pulmonary vascular resistance (106% +/- 1% vs 198% +/- 1%; p < 0.001); lowered tissue edema (82.1% +/- 0.4% vs 84.3% +/- 0.2%; p < 0.001), and myeloperoxidase activity (0.18 +/- 0.02 vs 0.35 +/- 0.02 deltaOD/min/mg protein; p < 0.001). In contrast, using either a white blood cell filter or modified solution separately improved but did not avoid the reperfusion injury, resulting in pulmonary function and tissue edema levels that were intermediate between group 1 (uncontrolled reperfusion) and group 4 (white blood cell filter and modified solution)., Conclusion: After 2 hours of warm pulmonary ischemia, (1) a severe lung injury occurs after uncontrolled reperfusion, (2) controlled reperfusion with either a modified reperfusion solution or white blood cell filter limits, but does not avoid, a lung reperfusion injury, (3) reperfusion using both a modified reperfusate and white blood cell filter results in complete preservation of pulmonary function. We therefore believe surgeons should control the reperfusate after lung transplantation to improve postoperative pulmonary function.

Objective: We previously demonstrated that calcium can be harmful to the hypoxic neonatal heart. Despite the fact that magnesium inhibits membrane transport of calcium, few studies have examined whether magnesium can prevent the deleterious effects of calcium in cardioplegic solutions., Methods: Twenty neonatal piglets (5 to 18 days old) underwent 60 minutes of ventilator hypoxia (inspired oxygen fraction 8% to 10%) followed by reoxygenation with the use of cardiopulmonary bypass before cardioplegic arrest to produce a clinically relevant hypoxic "stress" injury. The aorta was then crossclamped for 70 minutes with multidose blood cardioplegia. Ten piglets received a hypocalcemic (0.2 to 0.4 mmol/L) cardioplegic solution without (group 1, n = 5) or with magnesium (10 mEq/L) (group II, n = 5) supplementation. Ten other piglets were protected with a normocalcemic (1.0 to 1.2 mmol/L) cardioplegic solution without (group III, n = 5) or with magnesium (group IV, n = 5). Myocardial function was assessed by means of pressure volume loops and expressed as a percentage of control. Coronary vascular resistance was assessed during each cardioplegic infusion., Results: Adding magnesium to a hypocalcemic cardioplegic solution (groups I and II) had no effect: Both groups had complete preservation of postbypass systolic function (end-systolic elastance 101% vs 104%) and preload recruitable stroke work (101% vs 102%), minimal increase in diastolic stiffness (159% vs 153%), and no difference in myocardial tissue edema (78.8% vs 78.9%) or coronary vascular resistance. Conversely, when a normocalcemic cardioplegic solution was administered without magnesium supplementation (group III), the results were markedly poorer than results obtained with magnesium supplementation (group IV). Without magnesium, there was a marked reduction in postbypass systolic function (end-systolic elastance 49% vs 101%; p < 0.05), increased diastolic stiffness (276% vs 162%; p < 0.05), decreased preload recruitable stroke work (53% vs 102%; p < 0.05), increased myocardial tissue edema (80.0% vs 78.9%; p < 0.05), and a rise in coronary vascular resistance (p < 0.05). Magnesium supplementation of the normocalcemic cardioplegic solution, by contrast, resulted in complete functional recovery., Conclusions: This study demonstrates that (1) magnesium does not alter the cardioprotective effects of a hypocalcemic cardioplegic solution, (2) a normocalcemic cardioplegic solution is detrimental to neonatal myocardium subjected to a previous hypoxic stress, and (3) magnesium supplementation of normocalcemic cardioplegic solutions prevents the deleterious effects of calcium.

Background: Recent experimental studies have shown that acute hypoxia followed by abrupt reoxygenation using cardiopulmonary bypass (CPB) results in an unintended injury mediated by oxygen free radicals, which can be modified by initiating CPB at a lower fraction of inspired oxygen (FiO2) or by leukocyte filtration. However, the clinical relevance of these experimental studies has been questioned because chronic hypoxia may allow compensatory changes to occur., Methods: Seven acyanotic infants had CPB initiated at an FiO2 of 1.0. Of 21 cyanotic infants, 7 (group 1) had CPB initiated at an FiO2 of 1.0, 6 (group 2) at an FiO2 of 0.21, and 8 (group 3) underwent CPB using leukocyte filtration. Biopsy of right atrial tissue was performed before and 10 to 20 minutes after the initiation of CPB. The tissue was incubated in 4-mmol/L t-butylhydroperoxide (a strong oxidant), and the malondialdehyde (MDA) level was measured to determine the antioxidant reserve capacity. The more MDA produced, the greater was the depletion of tissue antioxidants secondary to oxygen free radical formation during reoxygenation., Results: There was no difference in the prebypass antioxidant reserve capacity between cyanotic and acyanotic hearts (492 +/- 72 versus 439 +/- 44 nmol MDA/g protein). However, after the initiation of CPB without leukocyte filtration, MDA production rose markedly in the cyanotic (groups 1 and 2) as compared with the acyanotic hearts (322% versus 40%; p < 0.05), indicating a depletion of antioxidants. In cyanotic hearts, initiating CPB at an FiO2 of 1.0 (group 1) resulted in increased MDA production (407% versus 227%) as compared with hearts in which CPB was initiated at an FiO2 of 0.21 (group 2), indicating a greater generation of oxygen free radicals in group 1. Conversely, there was only a minimal increase in MDA production in 8 of the 21 infants (group 3) in whom white blood cells were effectively filtered (19% versus 322%; p < 0.05)., Conclusions: First, increased amounts of oxygen free radicals are generated in cyanotic infants with the initiation of CPB. Second, this production is reduced by initiating CPB at an FiO2 of 0.21 or by effectively filtering white blood cells. Third, these changes parallel those seen in the acute experimental model, validating its use for future study.

Objectives: Blood cardioplegia predominates in the adult because it provides superior myocardial protection, especially in the ischemically stressed heart. However, the superiority of blood over crystalloid cardioplegia in the pediatric population is unproved. Furthermore, because many pediatric hearts undergo a preoperative stress such as hypoxia, it is important to compare the different methods of protection in both normal and hypoxic hearts., Methods: Twenty neonatal piglets were supported by cardiopulmonary bypass and subjected to 70 minutes of cardioplegic arrest. Of 10 nonhypoxic hearts, five (group 1) were protected with blood cardioplegia and five (group 2) with crystalloid cardioplegia (St. Thomas' Hospital solution). Ten other piglets underwent 60 minutes of ventilator hypoxia (inspired oxygen concentration 8% to 10%) before cardioplegic arrest. Five (group 3) were then protected with blood cardioplegia and the other five (group 4) with crystalloid cardioplegia. Myocardial function was assessed by means of pressure volume loops and expressed as a percentage of control. Coronary vascular resistance was measured with each infusion of cardioplegic solution., Results: No difference was noted between blood (group 1) or crystalloid cardioplegia (group 2) in nonhypoxic hearts regarding systolic function (end-systolic elastance 104% vs 103%), diastolic stiffness (156% vs 159%), preload recruitable stroke work (102% vs 101%), or myocardial tissue edema (78.9% vs 78.9%). Conversely, in hearts subjected to a hypoxic stress, blood cardioplegia (group 3) provided better protection than crystalloid cardioplegia (group 4) by preserving systolic function (end-systolic elastance 106% vs 40%; p < 0.05) and preload recruitable stroke work (103% vs 40%; p < 0.05); reducing diastolic stiffness (153% vs 240%; p < 0.05) and myocardial tissue edema (79.6% vs 80.1%); and preserving vascular function, as evidenced by unaltered coronary vascular resistance (p < 0.05)., Conclusion: This study demonstrates that (1) blood or crystalloid cardioplegia is cardioprotective in hearts not compromised by preoperative hypoxia and (2) blood cardioplegia is superior to crystalloid cardioplegia in hearts subjected to the preoperative stress of acute hypoxia.

Objectives: Recent studies have shown that an injury occurs when the hypoxic heart is suddenly reoxygenated (as occurs with cardiopulmonary bypass), resulting in myocardial depression, impaired oxygenation, and increased pulmonary vascular resistance. We hypothesize that this injury is, in part, due to oxygen-derived radicals produced by activated white cells and may therefore be ameliorated by limiting leukocytes in the bypass circuit., Methods: Fifteen neonatal piglets underwent 60 minutes of ventilator hypoxia (inspired oxygen fraction 8% to 10%), followed by reoxygenation with cardiopulmonary bypass at an inspired oxygen fraction of 100% for 90 minutes. In nine piglets (group 1) our routine bypass circuit was used with no modifications, and in six piglets (group 2) a leukocyte-depleting filter (Pall BC-1; Pall Biomedical Products Corporation, Glencoe, N.Y.) was inserted in the arterial line to lower the neutrophil count. Six additional piglets underwent 90 minutes of bypass without hypoxia (cardiopulmonary bypass controls). Postbypass myocardial and pulmonary function was assessed by pressure volume loops, arterial/alveolar ratio, and pulmonary vascular resistance index. Results are expressed as a percentage of control., Results: By comparison with group 1 piglets (reoxygenation without a filter), hypoxic piglets undergoing reoxygenation with a leukocyte-depleting filter (group 2) had improved myocardial systolic function (88% vs 52%; p < 0.05), diastolic compliance (175% vs 275%; p < 0.05), and preload recruitable stroke work (91% vs 54%; p < 0.05); had better preservation of the arterial/alveolar ratio (97% vs 74%; p < 0.05); and had less increase in pulmonary vascular resistance (229% vs 391%; p < 0.05). Furthermore, leukocyte filtration prevented adenosine triphosphate depletion or a change in tissue antioxidants. Conversely, unprotected piglets (group 1) exhibited lower levels of adenosine triphosphate and significant loss of tissue antioxidants. Indeed, the results in the leukocyte-filtered piglets (group 2) were nearly identical to those of piglets subjected to bypass without hypoxia (controls)., Conclusions: (1) This study demonstrates that a major component of the injury that occurs when the hypoxic heart is abruptly reoxygenated is caused by oxygen radicals produced by white blood cells; (2) this injury can be prevented by a leukocyte-depleting filter; and (3) avoidance of this injury improves postbypass myocardial and pulmonary function. These data suggest that leukocyte depletion should be used routinely in all children undergoing operations for cyanotic heart disease or extracorporeal membrane oxygenation.

Unlabelled: Surgeons often rely primarily on retrograde cardioplegia for myocardial protection, because it provides adequate left ventricular perfusion even in the presence of coronary artery disease. Clinically, however, adequate right ventricular perfusion by retrograde delivery has not been demonstrated. Using intraoperative transesophageal echocardiography, we examined retrograde delivery of cardioplegic solutions by contrast echocardiography, which directly assesses myocardial perfusion. In 15 patients (seven having coronary bypass and eight having valve operations), 4 ml of sonicated Isovue medium was injected retrograde via a coronary sinus catheter. Myocardial perfusion was assessed quantitatively by visual inspection and back-ground-subtracted videodensitometric analysis. In five patients undergoing aortic valve replacement, right and left coronary ostial drainage was estimated during retrograde infusion. Before the aortic crossclamp was removed, myocardial oxygen extraction was calculated in all 15 patients by first delivering warm blood cardioplegic solution for 2 minutes in a retrograde fashion and then taking samples from the cardioplegia line and aortic root. This determined the oxygen extraction ratio across the myocardium at the end of retrograde delivery. Warm blood cardioplegic solution was next given antegrade, and 15 seconds later samples were taken from the cardioplegia line and a right ventricular (acute marginal) vein to determine the oxygen extraction ratio across the right ventricle. As assessed by contrast echocardiography, retrograde infusion resulted in almost four times more perfusion to the left ventricular free wall and septum than to the right ventricular free wall (74 +/- 2 versus 69 +/- 2 versus 20 +/- 2, p < 0.05). In those five patients with an aortotomy the right ostial drainage was less than 5 ml/min whereas left ostial drainage was estimated at 80 ml/min during retrograde administration. Oxygen extraction across the myocardium supplied by retrograde infusion was low after 2 minutes. Conversely, when antegrade cardioplegia was started, right ventricular oxygen extraction rose fourfold (42% +/- 5% versus 11% +/- 1%, p < 0.05), demonstrating that retrograde cardioplegia had not adequately perfused the right ventricular myocardium., Conclusions: 1. Retrograde cardioplegia provides poor right ventricular myocardial perfusion as assessed by contrast echocardiography and coronary ostial drainage. (2) This poor perfusion is inadequate to meet myocardial demands as demonstrated by the high right ventricular oxygen extraction after a prolonged retrograde infusion. (3) Therefore surgeons must not rely solely on retrograde cardioplegia for right ventricular myocardial protection. This concept is especially important if continuous warm blood cardioplegia is used, because myocardial requirements are then higher.