Hypogammaglobulinemia after cardiopulmonary bypass in infants

Early predictors of bacterial pneumonia infection in children with congenital heart disease after cardiopulmonary bypass: a single-centre retrospective study

OBJECTIVES

The objective of this study was to evaluate the early predictors of bacterial pneumonia infection in children with congenital heart disease (CHD) after cardiopulmonary bypass (CPB).

DESIGN

Retrospective study.

SETTING

A freestanding tertiary paediatric hospital in China.

PARTICIPANTS

Patients admitted to the hospital due to CHD who underwent open-heart surgery.

OUTCOME MEASURES

We retrospectively reviewed and analysed data from 1622 patients with CHD after CPB from June 2018 to December 2020 at the Children's Hospital of Nanjing Medical University. Enrolled patients were assigned to an infection group or a non-infection group according to the presence of postoperative bacterial pneumonia infection, and the differences in clinical indicators were compared. Potential predictors were analysed by multivariate logistic regression analysis and area under the curve (AUC) analysis.

RESULTS

Among the 376 patients (23.2%) in the infection group, the three most common bacteria were Streptococcus pneumoniae in 67 patients (17.8%), Escherichia coli in 63 patients (16.8%) and Haemophilus influenzae in 53 patients (14.1%). The infection group exhibited a lower weight (8.0 (6.0-11.5) kg vs 11.0 (7.5-14.5) kg, p<0.001). In the infection group, procalcitonin (PCT) (ng/mL: 4.72 (1.38-9.52) vs 1.28 (0.47-3.74), p<0.001) and C reactive protein (CRP) (mg/L: 21.0 (12.1-32.0) vs 17.0 (10.0-27.0), p<0.001) levels were significantly greater than those in the non-infection group. Binary logistic regression analysis revealed that weight, PCT and CRP were independent risk factors for pulmonary bacterial infection after CPB. The AUCs of weight, PCT, CRP and PCT+CRP for predicting pulmonary bacterial infection after CPB were 0.632 (95% CI 0.600 to 0.664), 0.697 (95% CI 0.667 to 0.727), 0.586 (95% CI 0.554 to 0.618) and 0.694 (95% CI 0.664 to 0.724), respectively, and the cut-off values were ≤10.25 kg, ≥4.25 ng/mL, ≥6.50 mg/L and ≥0.20, respectively. The sensitivities were 69.7%, 54.0%, 93.9% and 70.2%, and the specificities were 53.5%, 77.7%, 19.4% and 59.1%, respectively.

CONCLUSIONS

In our study, weight, PCT and CRP were found to be independent predictors of pulmonary bacterial infection after CPB. Moreover, PCT was the most specific predictor, and CRP was the most sensitive independent predictor that might be beneficial for the early diagnosis of pulmonary bacterial infection after CPB in patients with CHD.

Hypogammaglobulinemia in neonates: illustrative cases and review of the literature

This article presents a review of causes of hypogammaglobulinemia in neonates utilizing illustrative cases to demonstrate commonly seen conditions. Overall, the causes of low immunoglobulin level can be divided into three main categories: decreased maternal transfer or production (due to physiological nadir, transient hypogammaglobulinemia of infancy, medication effects, or immunodeficiency), increased loss of immunoglobulins (from the gastrointestinal (GI) system, lymphatics, kidneys, skin disease, or blood loss) or destruction/suppression (from medication effects). Treatment of hypogammaglobulinemia is generally tailored to the underlying cause and condition of the patient. This can be through supportive care, prophylactic measures, or with immunoglobulin G (IgG) replacement at the recommendation of an immunologist.

Quality Report: Postoperative Guideline Implementation Reduces Length of Stay after Fontan Procedure

Introduction

Patients following the Fontan procedure have a physiology that results in prolonged pleural effusion, often delaying hospital discharge. The hospital length of stay (LOS) of patients following the Fontan procedure at our institution was significantly longer than the Society of Thoracic Surgery benchmark. This quality improvement project aimed to decrease hospital LOS in patients following the Fontan procedure from a baseline of 23 days to 7 days by January 1, 2021, and sustain indefinitely.

Methods

We implemented standardized postoperative clinical practice guidelines in April 2020. We designed guidelines using previously published protocols. Key features included an ambulatory PleurX drain (BD, Franklin Lakes, N.J.), diuresis with fluid restriction, and pulmonary vasodilation with supplemental oxygen and sildenafil. All patients were discharged from the hospital with a PleurX drain in place. We compared clinical outcome variables before and after guideline implementation. As a balancing measure, we tracked 30-day readmissions.

Results

One hundred seven patients underwent the Fontan procedure before guideline implementation from January 2015 to January 2020, with an average hospital LOS of 23 days. Postguideline implementation, 35 patients underwent the Fontan procedure from April 2020 to July 2022, with an average hospital LOS of 8 days in 2020, which further improved to an average hospital LOS of 7 days. There was no change in 30-day readmission after guideline implementation (24% pre versus 23% post; P = 0.86).

Conclusion

Implementing clinical practice guidelines for patients following the Fontan procedure led to an over 50% reduction in hospital LOS without increasing 30-day readmission.

Fresh frozen plasma prime and the level of gammaglobulin after pediatric cardiopulmonary bypass

Different organ perturbation and multiple complications might occur after cardiopulmonary bypass (CPB). A variety of solutions might be used for pump priming with different advantages and disadvantages. The advantage of fresh frozen plasma (FFP) inclusion in pump prime has been shown in post-CPB coagulation management. Acquired hypogammaglobulinemia is the disadvantage of albumin (ALB) pump prime. Our aim was to assess the impact of FFP prime on the post-pump serum level of immunoglobulin G (IgG) and its subclasses. Fifty-six patients under the age of 5 years old who were scheduled for cardiac surgery on CPB were randomly primed with FFP or ALB. Any innate or acquired immune deficiency was considered as exclusion criteria. The pre-CPB and 24-hour post-CPB collected blood samples were analyzed by the nephelometric method for the plasma level of IgG and its four subclasses. Twenty-two patients (mean age and weight of 13 months and 6.8 kilograms) in the ALB prime group and 26 patients (mean age and weight of 15 months and 8.1 kilograms) in the FFP prime group completed the study. Using paired t-test and repeated measures ANOVA test, patients in the ALB prime group had a significant drop in the post-CPB serum level of total IgG (597±138 mg/dL to 379±179 mg/dL, P value <0.001) and its two subclasses of IgG1 and IgG3. In contrast, there was a slight elevation in the serum level of total IgG (549±207 mg/dL to 630±180 mg/dL, P value =0.008) and its two subclasses of IgG2 and IgG4 in patients who had FFP prime solution. In conclusion, compared to the ALB prime solution, FFP inclusion in prime could hamper the pediatric post-CPB induced hypogammaglobulinemia.

Guidelines for Diuretic Utilization Reduce High Charge Medications

Decreasing practice variation and following evidence-based clinical guidelines improve patient outcomes and often reduce cost. Essentially all postsurgical cardiac patients require diuretics. The approach to diuresis in the pediatric cardiothoracic intensive care unit (CTICU) is not standardized. Our objective was to develop and implement guidelines for diuretic utilization in the CTICU to reduce high charge medication utilization while maintaining the delivery of high-quality care.

Reporter Cell Assessment of TLR4-Induced NF-κB Responses to Cell-Free Hemoglobin and the Influence of Biliverdin

Hemoglobin (Hb) released during red blood cell lysis can initiate TLR4-dependent signaling and trigger NF-κB activation in surrounding cells. Observations of chronic bleeding in various cancers leads us to hypothesize that Hb and Hb degradation products released from lysed RBC near cancer nests might modulate local TLR4-positive cells. We addressed the hypothesis in vitro by measuring Hb- and biliverdin (Bv)-induced NF-κB signaling in an engineered human TLR4 reporter cell model (HEK-Blue^TM hTLR4). Therein, TLR4 stimulation was assessed by measuring NF-κB-dependent secreted alkaline phosphatase (SEAP). hTLR4 reporter cells incubated with 8 ηM lipopolysaccharide (LPS) or 20-40 μM fungal mannoprotein (FM) produced significant amounts of SEAP. hTLR4 reporter cells also produced SEAP in response to human, but not porcine or bovine, Hb. HEK-Blue Null2^TM reporter cells lacking TLR4 did not respond to LPS, FM, or Hb. Bv was non-stimulatory in reporter cells. When Bv was added to Hb-stimulated reporter cells, SEAP production was reduced by 95%, but when Bv was applied during LPS and FM stimulation, SEAP production was reduced by 33% and 27%, respectively. In conclusion, Hb initiated NF-κB signaling that was dependent upon TLR4 expression and that Bv can act as a TLR4 antagonist. Moreover, this study suggests that hemorrhage and extravascular hemolysis could provide competitive Hb and Bv signaling to nearby cells expressing TLR4, and that this process could modulate NF-κB signaling in TLR4-positive cancer cells and cancer-infiltrating leukocytes.

A Prospective Observational Study of Hypogammaglobulinemia in the First Year After Lung Transplantation

Background

Immunosuppressive therapies have led to improved survival for lung transplant (LT) recipients but these therapies can lead to hypogammaglobulinemia (HGG) and potentially an increased risk of infection. Large prospective studies have not been performed to evaluate the impact of HGG on outcomes for LT recipients.

Methods

This is a single-center prospective observational study of LT recipients. Pretransplant and posttransplant IgG levels were measured and related to infection, rejection, antibiotic use, and immunosuppression use.

Results

One hundred thirty-three LT recipients were prospectively evaluated. Pretransplant IgG values were higher than IgG values at the time of transplant or any time thereafter (all P < 0.0001). Severe HGG (IgG < 400 mg/dL) was highest at the time of transplant (32.4%) while at 3, 6, 9, and 12 months posttransplant the prevalence of severe HGG was 7.4%, 7.5%, 8.9%, and 6.3%, respectively. Severe HGG was associated with 2 or more pneumonias (P = 0.0006) and increased number of antibiotic courses (P = 0.003) compared with the subjects without severe HGG. Pretransplant IgG level and less than 30% of pretransplant protective pneumococcal antibody levels were identified as pretransplant risk factors for severe HGG. In multivariate analysis, chronic obstructive pulmonary disease as the underlying disease and the use of basiliximab as the induction agent in conjunction with higher prednisone and mycophenolate dosing were most predictive of severe HGG (P = 0.005), whereas the combination of age, severe HGG and number of acute steroid courses were most predictive of total days of pneumonia (P = 0.0001).

Conclusions

Our large prospective study identifies risk factors for severe HGG after LT and demonstrates that LT recipients with severe HGG are at increased risk for recurrent pneumonias and more antibiotic courses.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Fluid Management

OBJECTIVE

In this Consensus Statement, we review the etiology and pathophysiology of fluid disturbances in critically ill children with cardiac disease. Clinical tools used to recognize pathologic fluid states are summarized, as are the mechanisms of action of many drugs aimed at optimal fluid management.

DATA SOURCES

The expertise of the authors and a review of the medical literature were used as data sources.

DATA SYNTHESIS

The authors synthesized the data in the literature in order to present clinical tools used to recognize pathologic fluid states. For each drug, the physiologic rationale, mechanism of action, and pharmacokinetics are synthesized, and the evidence in the literature to support the therapy is discussed.

CONCLUSIONS

Fluid management is challenging in critically ill pediatric cardiac patients. A myriad of causes may be contributory, including intrinsic myocardial dysfunction with its associated neuroendocrine response, renal dysfunction with oliguria, and systemic inflammation with resulting endothelial dysfunction. The development of fluid overload has been associated with adverse outcomes, including acute kidney injury, prolonged mechanical ventilation, increased vasoactive support, prolonged hospital length of stay, and mortality. An in-depth understanding of the many factors that influence volume status is necessary to guide optimal management.