Extracorporeal membrane oxygenation use in poisoning: a narrative review with clinical recommendations

CONTEXT

Poisoning may lead to respiratory failure, shock, cardiac arrest, or death. Extracorporeal membrane oxygenation (ECMO) may be used to provide circulatory support, termed venoarterial (VA) ECMO; or respiratory support termed venovenous (VV) ECMO. The clinical utility of ECMO in poisoned patients remains unclear and guidelines on its use in this setting are lacking.

OBJECTIVES

To perform a literature search and narrative review on the use of ECMO in poisonings. Additionally, to provide recommendations on the use of ECMO in poisonings from physicians with expertise in ECMO, medical toxicology, critical care, and emergency medicine.

METHODS

A literature search in Ovid MEDLINE from 1946 to October 14, 2020, was performed to identify relevant articles with a strategy utilizing both MeSH terms and adjacency searching that encompassed both extracorporeal life support/ECMO/Membrane Oxygenation concepts and chemically-induced disorders/toxicity/poisoning concepts, which identified 318 unique records. Twelve additional manuscripts were identified by the authors for a total of 330 articles for screening, of which 156 were included for this report.

NARRATIVE LITERATURE REVIEW

The use of ECMO in poisoned patients is significantly increasing over time. Available retrospective data suggest that patients receiving VA ECMO for refractory shock or cardiac arrest due to poisoning have lower mortality as compared to those who receive VA ECMO for non-poisoning-related indications. Poisoned patients treated with ECMO have reduced mortality as compared to those treated without ECMO with similar severity of illness and after adjusted analyses, regardless of the type of ingestion. This is especially evident for poisoned patients with refractory cardiac arrest placed on VA ECMO (termed extracorporeal cardiopulmonary resuscitation [ECPR]).

INDICATIONS

We suggest VA ECMO be considered for poisoned patients with refractory cardiogenic shock (continued shock with myocardial dysfunction despite fluid resuscitation, vasoactive support, and indicated toxicologic therapies such as glucagon, intravenous lipid emulsion, hyperinsulinemia euglycemia therapy, or others), and strongly considered for patients with cardiac arrest in institutions which are structured to deliver effective ECPR. VV ECMO should be considered in poisoned patients with ARDS or severe respiratory failure according to traditional indications for ECMO in this setting.

CONTRAINDICATIONS

Patients with pre-existing comorbidities with low expected survival or recovery. Relative contraindications vary based on each center's experience but often include: severe brain injury; advanced age; unrepaired aortic dissection or severe aortic regurgitation in VA ECMO; irreversible organ injury; contraindication to systemic anticoagulation, such as severe hemorrhage.

CONCLUSIONS

ECMO may provide hemodynamic or respiratory support to poisoned patients while they recover from the toxic exposure and metabolize or eliminate the toxic agent. Available literature suggests a potential benefit for ECMO use in selected poisoned patients with refractory shock, cardiac arrest, or respiratory failure. Future studies may help to further our understanding of the use and complications of ECMO in poisoned patients.

Discharge instructions for youth sports-related concussions in the emergency department, 2004 to 2012

OBJECTIVE

To evaluate the effect of the Centers for Disease Control and Prevention (CDC) Heads-Up concussion campaign on appropriateness of discharge instructions for youth sports-related concussion (SRC) patients presenting to a pediatric emergency department (ED).

DESIGN

Retrospective cohort study.

SETTING

Pediatric ED.

PATIENTS

Children up to 18 years.

ASSESSMENT OF RISK FACTORS

A retrospective chart review was conducted on patients evaluated from 2004 to 2012. Patients were selected by ICD-9 code for having a concussion during a sporting activity.

MAIN OUTCOME MEASURES

Discharge instructions were reviewed for recommendations for cognitive rest, physical rest, primary care physician follow-up, and referral to a concussion specialist or center.

RESULTS

There were 497 youth SRCs from 392 908 total ED visits. Overall, only 66% had appropriate discharge recommendations. This improved to 75% after 2010, which was not statistically significant (odds ratio = 1.02, P = 0.179). Only 4% of patients received a recommendation of cognitive rest, which only increased to 12% of the patients seen after 2010. Finally, referrals to a sports concussion specialist or center dramatically increased from an average of 8% to 43% after 2010.

CONCLUSIONS

Even with the CDC Heads-Up campaign on concussion education, there is still need to improve appropriateness of discharge instructions for youth SRCs. There have been dramatic increases in referrals to sports concussion specialists and centers after 2010.

Mucolipidosis type IV protein TRPML1-dependent lysosome formation

Lysosomes are dynamic organelles that undergo cycles of fusion and fission with themselves and with other organelles. Following fusion with late endosomes to form hybrid organelles, lysosomes are reformed as discrete organelles. This lysosome reformation or formation is a poorly understood process that has not been systematically analyzed and that lacks known regulators. In this study, we quantitatively define the multiple steps of lysosome formation and identify the first regulator of this process.

Systematic screens for proteins that interact with the mucolipidosis type IV protein TRPML1

Mucolipidosis type IV is a lysosomal storage disorder resulting from mutations in the MCOLN1 gene, which encodes the endosomal/lysosomal Transient Receptor Potential channel protein mucolipin-1/TRPML1. Cells isolated from Mucolipidosis type IV patients and grown in vitro and in in vivo models of this disease both show several lysosome-associated defects. However, it is still unclear how TRPML1 regulates the transport steps implicated by these defects. Identifying proteins that associate with TRPML1 will facilitate the elucidation of its cellular and biochemical functions. We report here two saturation screens for proteins that interact with TRPML1: one that is based on immunoprecipitation/mass spectrometry and the other using a genetic yeast two-hybrid approach. From these screens, we identified largely non-overlapping proteins, which represent potential TRPML1-interactors., Using additional interaction assays on some of the potential interactors from each screen, we validated some proteins as candidate TRPML1 interactors In addition, our analysis indicates that each of the two screens not only identified some false-positive interactors, as expected from any screen, but also failed to uncover potential TRPML1 interactors. Future studies on the true interactors, first identified in these screens, will help elucidate the structure and function of protein complexes containing TRPML1.

Challenges posed by non-random missing quality of life data in an advanced-stage colorectal cancer clinical trial

Effects of variations in agent, dose, and route of treatment administration on patient reported quality of life (QOL) were examined for 279 patients enrolled on a seven-arm randomized clinical trial (S8905) of 5-FU and its modulation for advanced colorectal cancer. Patients completed QOL questionnaires at randomization and weeks 6, 11, and 21 post-randomization with five QOL endpoints considered primary: three treatment-specific symptoms (stomatitis, diarrhea, and hand/foot sensitivity); physical functioning; and emotional functioning. Patient compliance with the QOL assessment schedule was good, supporting the feasibility of including QOL measures in cooperative group trials. However, death and deteriorating health produced substantial missing data. Cross-sectional analyses indicated that the seven therapeutic arms did not differ in their impact on QOL. Unfortunately, longitudinal analyses of the QOL data were inappropriate given non-random missing data. Graphical presentation of non-random missing data identified the seriousness of this problem and its effect on potential conclusions about QOL during treatment. This problem appears to be particularly challenging in the context of advanced-stage disease. Failure to recognize the presence of non-random missing data can lead to serious overestimates of patient QOL over time.

Improving breast self-examination compliance: a Southwest Oncology Group randomized trial of three interventions

BACKGROUND

Only 20-40% of U.S. women conduct breast self-examination (BSE). This Southwest Oncology Group experimental study compared the impact of three interventions on BSE compliance.

METHODS

Subjects were randomly assigned to one of three arms: (1) physician message; (2) physician message and BSE class; or (3) physician message, BSE class, and reinforcement (phone and postcard). Compliance (frequency and accuracy) was measured by interview at intake and at 6 months and by phone contact at 1 year. Logistic and multiple regression were employed.

RESULTS

This analysis included 2,233 subjects from six institutions. At 1 year the percentages of women doing BSE were 59, 62, and 78% for Arms 1-3, respectively; gains over intake frequency (27% average) were significant within each arm (P < or = 0.0001). At both 6 months and 1 year the differences between Arm 1 and Arm 2 average accuracy scores and the differences between Arm 2 and Arm 3 in the percentage of women doing BSE were significant (P < or = 0.0001). Findings within institutions were consistent with the overall findings.

CONCLUSIONS

The addition of a BSE class increased accuracy over physician message alone; physician message, BSE class, and reinforcement gave the highest percentage of women doing BSE.

Role of recombinant interferon alfa-2a maintenance in patients with limited-stage small-cell lung cancer responding to concurrent chemoradiation: a Southwest Oncology Group study

PURPOSE

This study was designed to determine if recombinant interferon alfa-2a (rIFN alpha-2a) could prolong remission duration and/or survival in patients with limited-stage small-cell lung cancer (SCLC) who achieved an objective response to chemoradiotherapy. A secondary end point was to assess the toxicity of chronic IFN administration.

PATIENTS AND METHODS

One hundred seventy-one of 215 eligible patients achieved an objective response and were eligible to receive rIFN alpha-2a (3 million units [MU]/m2 subcutaneously three times per week escalated to 9 MU/m2 as tolerated) or observation for 2 years.

RESULTS

One hundred thirty-two of 140 registered patients were eligible. Sixty-four patients were randomized to receive IFN and 68 to observation alone. The median time from randomization to progression was 9 months on the IFN arm and 10 months on the observation arm (P = .72). The overall median survival time was 16 months on the observation arm versus 13 months on the IFN arm (P = .77). Significant toxicities occurred in the rIFN alpha-2a arm. Grade 3 or higher toxicities included malaise, fatigue, and/or lethargy (30%), leukopenia (14%), neutropenia (13%), dyspnea (13%), nausea (11%), and respiratory infection (6%). Forty-three patients discontinued treatment due to intolerable side effects.

CONCLUSION

rIFN alpha-2a in the dose and schedule used in this study failed to prolong response duration or survival in patients with limited-stage SCLC who had previously responded to an induction chemoradiotherapy program. Failure may have been partly related to poor tolerance and inability to complete therapy.

Chemoradiotherapy with or without granulocyte-macrophage colony-stimulating factor in the treatment of limited-stage small-cell lung cancer: a prospective phase III randomized study of the Southwest Oncology Group

PURPOSE

This phase III randomized trial was designed to determine if granulocyte-macrophage colony-stimulating factor (GM-CSF) reduces the hematologic toxicity and morbidity induced by chemoradiotherapy in limited-stage small-cell lung cancer (SCLC).

METHODS

This multicenter prospective trial randomized 230 patients to receive chemotherapy and radiotherapy (RT) with or without GM-CSF given on days 4 to 18 of each of six cycles. The primary end point was hematologic toxicity. Secondary end points included the following: nonhematologic toxicities; days of (1) fever, (2) antibiotics, (3) hospitalization, and (4) infection; number of transfusions; drug doses delivered; and response rates and survival.

RESULTS

There was a statistically significant increase in the frequency and duration of life-threatening thrombocytopenia (P < .001) in patients randomized to GM-CSF. GM-CSF patients had significantly more toxic deaths (P < .01), more nonhematologic toxicities, more days in hospital, a higher incidence of intravenous (IV) antibiotic usage, and more transfusions. Patients randomized to GM-CSF had higher WBC and neutrophil nadirs (P < .01), but no significant difference in the frequency of grade 4 leukopenia or neutropenia. Patients randomized to GM-CSF had a lower complete response rate (36% v 44%), but the differences were not significant (P = .29). There were no significant differences in survival (median, 14 months on GM-CSF and 17 months on no GM-CSF; P = .15).

CONCLUSION

GM-CSF, as delivered in this study, should not be included with concurrent chemoradiotherapy treatment programs for limited-stage SCLC. The simultaneous use of hematopoietic colony-stimulating factors (CSFs) and chemoradiotherapy should be performed only in experimental settings. Chemoradiotherapy programs with cisplatin and etoposide ([VP-16] PE) and simultaneous chest RT produce grade 4 neutropenia and thrombocytopenia in a small-enough proportion of patients that prophylactic hematopoietic growth factors are clinically unnecessary.