MARCELO PARK

(Fonte: Lattes)
Índice h a partir de 2011
24
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/51 - Laboratório de Emergências Clínicas, Hospital das Clínicas, Faculdade de Medicina

Resultados de Busca

Agora exibindo 1 - 10 de 23
  • article 6 Citação(ões) na Scopus
  • article 13 Citação(ões) na Scopus
    Ânion gap corrigido para albumina, fosfato e lactato é um bom preditor de íon gap forte em pacientes enfermos graves: estudo de coorte em nicho
    (2013) ZAMPIERI, Fernando Godinho; PARK, Marcelo; RANZANI, Otavio Tavares; MACIEL, Alexandre Toledo; SOUZA, Heraldo Possolo de; CRUZ NETO, Luiz Monteiro da; SILVA, Fabiano Pinheiro da
    OBJECTIVE: Corrected anion gap and strong ion gap are commonly used to estimate unmeasured anions. We evaluated the performance of the anion gap corrected for albumin, phosphate and lactate in predicting strong ion gap in a mixed population of critically ill patients. We hypothesized that anion gap corrected for albumin, phosphate and lactate would be a good predictor of strong ion gap, independent of the presence of metabolic acidosis. In addition, we evaluated the impact of strong ion gap at admission on hospital mortality. METHODS: We included 84 critically ill patients. Correlation and agreement between the anion gap corrected for albumin, phosphate and lactate and strong ion gap was evaluated by the Pearson correlation test, linear regression, a Bland-Altman plot and calculating interclass correlation coefficient. Two subgroup analyses were performed: one in patients with base-excess <-2mEq/L (low BE group - lBE) and the other in patients with base-excess >-2mEq/L (high BE group - hBE). A logistic regression was performed to evaluate the association between admission strong ion gap levels and hospital mortality. RESULTS: There was a very strong correlation and a good agreement between anion gap corrected for albumin, phosphate and lactate and strong ion gap in the general population (r2=0.94; bias 1.40; limits of agreement -0.75 to 3.57). Correlation was also high in the lBE group (r2=0.94) and in the hBE group (r2=0.92). High levels of strong ion gap were present in 66% of the whole population and 42% of the cases in the hBE group. Strong ion gap was not associated with hospital mortality by logistic regression. CONCLUSION: Anion gap corrected for albumin, phosphate and lactate and strong ion gap have an excellent correlation. Unmeasured anions are frequently elevated in critically ill patients with normal base-excess. However, there was no association between unmeasured anions and hospital mortality.
  • article 1 Citação(ões) na Scopus
    Análise do comportamento do sódio ao longo de 24 horas de terapia renal substitutiva
    (2016) ROMANO, Thiago Gomes; MARTINS, Cassia Pimenta Barufi; MENDES, Pedro Vitale; BESEN, Bruno Adler Maccagnan Pinheiro; ZAMPIERI, Fernando Godinho; PARK, Marcelo
    ABSTRACT Objective: The aim of this study was to investigate the clinical and laboratorial factors associated with serum sodium variation during continuous renal replacement therapy and to assess whether the perfect admixture formula could predict 24-hour sodium variation. Methods: Thirty-six continuous renal replacement therapy sessions of 33 patients, in which the affluent prescription was unchanged during the first 24 hours, were retrieved from a prospective collected database and then analyzed. A mixed linear model was performed to investigate the factors associated with large serum sodium variations (≥ 8mEq/L), and a Bland-Altman plot was generated to assess the agreement between the predicted and observed variations. Results: In continuous renal replacement therapy 24-hour sessions, SAPS 3 (p = 0.022) and baseline hypernatremia (p = 0.023) were statistically significant predictors of serum sodium variations ≥ 8mEq/L in univariate analysis, but only hypernatremia demonstrated an independent association (β = 0.429, p < 0.001). The perfect admixture formula for sodium prediction at 24 hours demonstrated poor agreement with the observed values. Conclusions: Hypernatremia at the time of continuous renal replacement therapy initiation is an important factor associated with clinically significant serum sodium variation. The use of 4% citrate or acid citrate dextrose - formula A 2.2% as anticoagulants was not associated with higher serum sodium variations. A mathematical prediction for the serum sodium concentration after 24 hours was not feasible.
  • article 8 Citação(ões) na Scopus
    Adaptação metabólica diante de hipercapnia persistente aguda em pacientes submetidos à ventilação mecânica por síndrome do desconforto respiratório agudo
    (2016) ROMANO, Thiago Gomes; CORREIA, Mario Diego Teles; MENDES, Pedro Vitale; ZAMPIERI, Fernando Godinho; MACIEL, Alexandre Toledo; PARK, Marcelo
    ABSTRACT Objective: Hypercapnia resulting from protective ventilation in acute respiratory distress syndrome triggers metabolic pH compensation, which is not entirely characterized. We aimed to describe this metabolic compensation. Methods: The data were retrieved from a prospective collected database. Variables from patients' admission and from hypercapnia installation until the third day after installation were gathered. Forty-one patients with acute respiratory distress syndrome were analyzed, including twenty-six with persistent hypercapnia (PaCO2 > 50mmHg > 24 hours) and 15 non-hypercapnic (control group). An acid-base quantitative physicochemical approach was used for the analysis. Results: The mean ages in the hypercapnic and control groups were 48 ± 18 years and 44 ± 14 years, respectively. After the induction of hypercapnia, pH markedly decreased and gradually improved in the ensuing 72 hours, consistent with increases in the standard base excess. The metabolic acid-base adaptation occurred because of decreases in the serum lactate and strong ion gap and increases in the inorganic apparent strong ion difference. Furthermore, the elevation in the inorganic apparent strong ion difference occurred due to slight increases in serum sodium, magnesium, potassium and calcium. Serum chloride did not decrease for up to 72 hours after the initiation of hypercapnia. Conclusion: In this explanatory study, the results indicate that metabolic acid-base adaptation, which is triggered by acute persistent hypercapnia in patients with acute respiratory distress syndrome, is complex. Furthermore, further rapid increases in the standard base excess of hypercapnic patients involve decreases in serum lactate and unmeasured anions and increases in the inorganic apparent strong ion difference by means of slight increases in serum sodium, magnesium, calcium, and potassium. Serum chloride is not reduced.
  • article 7 Citação(ões) na Scopus
    Adesão a um protocolo de profilaxia de úlcera de estresse em pacientes críticos: estudo de coorte prospectiva
    (2020) SANTOS, Yuri de Albuquerque Pessoa dos; YOUNES-IBRAHIM, Mauricio Staib; CROZATTI, Lucas Lonardoni; RAGLIONE, Dante; CARDOZO JUNIOR, Luis Carlos Maia; BESEN, Bruno Adler Maccagnan Pinheiro; TANIGUCHI, Leandro Utino; PARK, Marcelo; MENDES, Pedro Vitale
    ABSTRACT Objective: To evaluate adherence to the stress ulcer prophylaxis protocol in critically ill patients at a tertiary university hospital. Methods: In this prospective cohort study, we included all adult patients admitted to the medical and surgical intensive care units of an academic tertiary hospital. Our sole exclusion criterion was upper gastrointestinal bleeding at intensive care unit admission. We collected baseline variables and stress ulcer prophylaxis indications according to the institutional protocol and use of prophylaxis. Our primary outcome was adherence to the stress ulcer prophylaxis protocol. Secondary outcomes were appropriate use of stress ulcer prophylaxis, upper gastrointestinal bleeding incidence and factors associated with appropriate use of stress ulcer prophylaxis. Results: Two hundred thirty-four patients were enrolled from July 2nd through July 31st, 2018. Patients were 52 ± 20 years old, 125 (53%) were surgical patients, and the mean SAPS 3 was 52 ± 20. In the longitudinal follow-up, 1499 patient-days were studied; 1069 patient-days had stress ulcer prophylaxis indications, and 777 patient-days contained prophylaxis use (73% stress ulcer prophylaxis protocol adherence). Of the 430 patient-days without stress ulcer prophylaxis indications, 242 involved prophylaxis (56% inappropriate stress ulcer prophylaxis use). The overall appropriate use of stress ulcer prophylaxis was 64%. Factors associated with proper stress ulcer prophylaxis prescription were mechanical ventilation OR 2.13 (95%CI 1.64 - 2.75) and coagulopathy OR 2.77 (95%CI 1.66 - 4.60). The upper gastrointestinal bleeding incidence was 12.8%. Conclusion: Adherence to the stress ulcer prophylaxis protocol was low and inappropriate use of stress ulcer prophylaxis was frequent in this cohort of critically ill patients.
  • article 6 Citação(ões) na Scopus
    Oxigenação por membrana extracorpórea para síndrome do desconforto respiratório agudo grave em pacientes adultos: revisão sistemática e metanálise
    (2019) MENDES, Pedro Vitale; MELRO, Livia Maria Garcia; LI, Ho Yeh; JOELSONS, Daniel; ZIGAIB, Rogerio; RIBEIRO, José Mauro da Fonseca Pestana; BESEN, Bruno Adler Maccagnan Pinheiro; PARK, Marcelo
    ABSTRACT Objective: The evidence of improved survival with the use of extracorporeal membrane oxygenation (ECMO) in acute respiratory distress syndrome is still uncertain. Methods: This systematic review and meta-analysis was registered in the PROSPERO database with the number CRD-42018098618. We performed a structured search of Medline, Lilacs, and ScienceDirect for randomized controlled trials evaluating the use of ECMO associated with (ultra)protective mechanical ventilation for severe acute respiratory failure in adult patients. We used the Cochrane risk of bias tool to evaluate the quality of the evidence. Our primary objective was to evaluate the effect of ECMO on the last reported mortality. Secondary outcomes were treatment failure, hospital length of stay and the need for renal replacement therapy in both groups. Results: Two randomized controlled studies were included in the meta-analysis, comprising 429 patients, of whom 214 were supported with ECMO. The most common reason for acute respiratory failure was pneumonia (60% - 65%). Respiratory ECMO support was associated with a reduction in last reported mortality and treatment failure with risk ratios (RR: 0.76; 95%CI 0.61 - 0.95 and RR: 0.68; 95%CI 0.55 - 0.85, respectively). Extracorporeal membrane oxygenation reduced the need for renal replacement therapy, with a RR of 0.88 (95%CI 0.77 - 0.99). Intensive care unit and hospital lengths of stay were longer in ECMO-supported patients, with an additional P50th 14.84 (P25th - P75th: 12.49 - 17.18) and P50th 29.80 (P25th - P75th: 26.04 - 33.56] days, respectively. Conclusion: Respiratory ECMO support in severe acute respiratory distress syndrome patients is associated with a reduced mortality rate and a reduced need for renal replacement therapy but a substantial increase in the lengths of stay in the intensive care unit and hospital. Our results may help bedside decision-making regarding ECMO initiation in patients with severe respiratory distress syndrome.
  • article 8 Citação(ões) na Scopus
    Oferta de oxigênio, remoção de dióxido de carbono, transferência de energia aos pulmões e comportamento da hipertensão pulmonar durante o suporte com oxigenação por membrana extracorpórea: um modelo matemático
    (2019) BESEN, Bruno Adler Maccagnan Pinheiro; ROMANO, Thiago Gomes; ZIGAIB, Rogerio; MENDES, Pedro Vitale; MELRO, Lívia Maria Garcia; PARK, Marcelo
    ABSTRACT Objective: To describe (1) the energy transfer from the ventilator to the lungs, (2) the match between venous-venous extracorporeal membrane oxygenation (ECMO) oxygen transfer and patient oxygen consumption (VO2), (3) carbon dioxide removal with ECMO, and (4) the potential effect of systemic venous oxygenation on pulmonary artery pressure. Methods: Mathematical modeling approach with hypothetical scenarios using computer simulation. Results: The transition from protective ventilation to ultraprotective ventilation in a patient with severe acute respiratory distress syndrome and a static respiratory compliance of 20mL/cm H2O reduced the energy transfer from the ventilator to the lungs from 35.3 to 2.6 joules/minute. A hypothetical patient, hyperdynamic and slightly anemic with VO2 = 200mL/minute, can reach an arterial oxygen saturation of 80%, while maintaining the match between the oxygen transfer by ECMO and the VO2 of the patient. Carbon dioxide is easily removed, and normal PaCO2 is easily reached. Venous blood oxygenation through the ECMO circuit may drive the PO2 stimulus of pulmonary hypoxic vasoconstriction to normal values. Conclusion: Ultraprotective ventilation largely reduces the energy transfer from the ventilator to the lungs. Severe hypoxemia on venous-venous-ECMO support may occur despite the matching between the oxygen transfer by ECMO and the VO2 of the patient. The normal range of PaCO2 is easy to reach. Venous-venous-ECMO support potentially relieves hypoxic pulmonary vasoconstriction.
  • article 5 Citação(ões) na Scopus
    Despertar, exercitar, sentar-se, deambular e extubar: uma mudança nos paradigmas para pacientes mecanicamente ventilados
    (2014) PARK, Marcelo; PIRES-NETO, Ruy Camargo; NASSAR JUNIOR, Antonio Paulo
  • article 1 Citação(ões) na Scopus
    Investigação da associação de dois oxigenadores em paralelo ou em série durante o suporte respiratório com oxigenação por membrana extracorpórea
    (2022) MELRO, Livia Maria Garcia; SANTOS, Yuri de Albuquerque Pessoa dos; CARDOZO JÚNIOR, Luis Carlos Maia; BESEN, Bruno Adler Maccagnan Pinheiro; ZIGAIB, Rogério; FORTE, Daniel Neves; MENDES, Pedro Vitale; PARK, Marcelo
    ABSTRACT Objective: To characterize the pressures, resistances, oxygenation, and decarboxylation efficacy of two oxygenators associated in series or in parallel during venous-venous extracorporeal membrane oxygenation support. Methods: Using the results of a swine severe respiratory failure associated with multiple organ dysfunction venous-venous extracorporeal membrane oxygenation support model and mathematical modeling, we explored the effects on oxygenation, decarboxylation and circuit pressures of in-parallel and in-series associations of oxygenators. Results: Five animals with a median weight of 80kg were tested. Both configurations increased the oxygen partial pressure after the oxygenators. The return cannula oxygen content was also slightly higher, but the impact on systemic oxygenation was minimal using oxygenators with a high rated flow (~ 7L/minute). Both configurations significantly reduced the systemic carbon dioxide partial pressure. As the extracorporeal membrane oxygenation blood flow increased, the oxygenator resistance decreased initially with a further increase with higher blood flows but with a small clinical impact. Conclusion: Association of oxygenators in parallel or in series during venous-venous extracorporeal membrane oxygenation support provides a modest increase in carbon dioxide partial pressure removal with a slight improvement in oxygenation. The effect of oxygenator associations on extracorporeal circuit pressures is minimal.