Prevalence and clinical implications of heightened plastic chemical exposure in pediatric patients undergoing cardiopulmonary bypass

BACKGROUND

Phthalate chemicals are used to manufacture plastic medical products, including many components of cardiopulmonary bypass (CPB) circuits. We aimed to quantify iatrogenic phthalate exposure in pediatric patients undergoing cardiac surgery and examine the link between phthalate exposure and postoperative outcomes.

STUDY DESIGN AND METHODS

The study included pediatric patients undergoing (n=122) unique cardiac surgeries at Children's National Hospital. For each patient, a single plasma sample was collected preoperatively and two additional samples were collected postoperatively upon return from the operating room and the morning after surgery. Concentrations of di(2-ethylhexyl) phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry.

RESULTS

Patients were subdivided into three groups, according to surgical procedure: (1) cardiac surgery not requiring CPB support, (2) cardiac surgery requiring CPB with a crystalloid prime, and (3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with an RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience postoperative complications. RBC washing was an effective strategy to reduce phthalate levels in CPB prime.

DISCUSSION

Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with an RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.

Prevalence and Clinical Implications of Heightened Plastic Chemical Exposure in Pediatric Patients Undergoing Cardiopulmonary Bypass

Importance

Phthalate chemicals are used to manufacture disposable plastic medical products, including blood storage bags and components of cardiopulmonary bypass (CPB) circuits. During cardiac surgery, patients can be inadvertently exposed to phthalate chemicals that are released from these plastic products.

Objective

To quantify iatrogenic phthalate chemical exposure in pediatric patients undergoing cardiac surgery, and examine the link between phthalate exposure and post-operative outcomes.

Design Setting and Participants

The study cohort included 122 pediatric patients undergoing cardiac surgery at Children's National Hospital. For each patient, a single plasma sample was collected pre-operatively and two additional samples were collected post-operatively upon return from the operating room (post-operative day 0) and the morning after surgery (post-operative day 1).

Exposures

Concentrations of di(2-ethylhexyl)phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry.

Main Outcomes and Measures

Plasma concentrations of phthalates, post-operative blood gas measurements, and post-operative complications.

Results

Study subjects were subdivided into three groups, according to surgical procedure: 1) cardiac surgery not requiring CPB support, 2) cardiac surgery requiring CPB with crystalloid prime, and 3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience post-operative complications, including arrhythmias, low cardiac output syndrome, and additional post-operative interventions. RBC washing was an effective strategy to reduce DEHP levels in CPB prime.

Conclusions and Relevance

Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.

Key Points

Question: Is cardiac surgery with cardiopulmonary bypass a significant source of phthalate chemical exposure in pediatric patients?Findings: In this study of 122 pediatric cardiac surgery patients, phthalate metabolites were quantified from blood samples before and after surgery. Phthalate concentrations were highest in patients undergoing cardiopulmonary bypass with red blood cell-based prime. Heightened phthalate exposure was associated with post-operative complications.Meaning: Cardiopulmonary bypass is a significant source of phthalate chemical exposure, and patients with heightened exposure may be at greater risk for postoperative cardiovascular complications.

Cardiovascular surgery in very low birth weight (≤1500 g) neonates

OBJECTIVES

Low birth weight and prematurity are known risks of increased morbidity and mortality with undergoing cardiovascular surgery. Our aim was to review the outcomes of very low birth weight (≤1500 g) patients who have undergone cardiovascular surgery.

METHODS

A retrospective review was performed for 32 very low birth weight (≤1500 g) patients who underwent cardiovascular surgery from 2004 to 2021 in our institution.

RESULTS

Fifteen patients weighting ≤1500 g at surgery (≤1500-g group) were compared to 17 patients born with a weigh of ≤1500 g and weighting between 1500 and 2500 g at surgery (>1500- to ≤2500-g group) in this study. In-hospital mortality was 33% (5/15) in the ≤1500-g group and 24% (4/17) in the >1500- to ≤2500-g group (P = 0.55). All patients with simple biventricular lesion survived following full repair. The occurrence of postoperative intracerebral haemorrhage was significantly higher in those operated at weight ≤1500 g than those weighting >1500 to ≤2500 g (40% vs 0%; P = 0.01). The 1- and 3-year survival rates were 66.0 ± 12.4% and 46.2 ± 14.8% in the ≤1500-g group and 76.5 ± 10.3% and 70.6 ± 11.1% in the >1500- to ≤2500-g group (log-rank P = 0.12).

CONCLUSIONS

Cardiac surgery for a very low birth weight neonate resulted in a high early and late mortality. Early surgery is only acceptable for simple biventricular lesions if needed. Delayed surgery seems to provide better long-term outcomes in patients with complex lesions. Alternative strategies for neonatal cardiopulmonary bypass should be investigated in patients with complex biventricular and single ventricular lesions.

Cardiac surgery 2016 reviewed

For the year 2016, more than 20,000 published references can be found in Pubmed when entering the search term "cardiac surgery". Publications last year have helped to more clearly delineate the fields where classic surgery and modern interventional techniques overlap. The field of coronary bypass surgery (partially compared to percutaneous coronary intervention) was enriched by five large prospective randomized trials. The value of CABG for complex coronary disease was reconfirmed and for less complex main stem lesions, PCI was found potentially equal. For aortic valve treatment, more evidence was presented for the superiority of transcatheter aortic valve implantation for patients with intermediate risk. However, the 2016 evidence argued against the liberal expansion to the low-risk field, where conventional aortic valve replacement still appears superior. For the mitral valve, many publications emphasized the significant impact of mitral valve reconstruction on survival in structural mitral regurgitation. In addition, there were many relevant and other interesting contributions from the purely operative arena in the fields of coronary revascularization, surgical treatment of valve disease, terminal heart failure (i.e., transplantation and ventricular assist devices), and aortic surgery. While this article attempts to summarize the most pertinent publications it does not have the expectation of being complete and cannot be free of individual interpretation. As in recent years, it provides a condensed summary that is intended to give the reader "solid ground" for up-to-date decision-making in cardiac surgery.

Highly Electrically Conducting Glass-Graphene Nanoplatelets Hybrid Coatings

Hybrid coatings consisting of a heat resistant Y2O3-Al2O3-SiO2 (YAS) glass containing 2.3 wt % of graphene nanoplatelets (GNPs) were developed by flame spraying homogeneous ceramic powders-GNP granules. Around 40% of the GNPs survived the high spraying temperatures and were distributed along the splat-interfaces, forming a percolated network. These YAS-GNP coatings are potentially interesting in thermal protection systems and electromagnetic interference shields for aerospace applications; therefore silicon carbide (SiC) materials at the forefront of those applications were employed as substrates. Whereas the YAS coatings are nonconductive, the YAS-GNP coatings showed in-plane electrical conductivity (∼10(2) S·m(-1)) for which a low percolation limit (below 3.6 vol %) is inferred. Indentation tests revealed the formation of a highly damaged indentation zone showing multiple shear displacements between adjacent splats probably favored by the graphene sheets location. The indentation radial cracks typically found in brittle glass coatings are not detected in the hybrid coatings that are also more compliant.