Uso de Índices Aterogênicos como Métodos de Avaliação das Doenças Ateroscleróticas Clínicas / Use of Atherogenic Indices as Assessment Methods of Clinical Atherosclerotic Diseases

Resumo Fundamento A busca por métodos clinicamente úteis de avaliação de doenças ateroscleróticas, com boa acurácia, de baixo custo, sem invasividade e de fácil manejo, há anos vem sendo estimulada. Dessa forma, os índices aterogênicos avaliados deste estudo podem se encaixar nesta demanda crescente. Objetivos Avaliar o potencial dos índices aterogênicos como métodos de avaliação de pacientes portadores de aterosclerose clínica. Métodos Estudo transversal de centro único, por meio do qual foram avaliados os índices de Castelli I e II, índice aterogênico plasmático (IAP), índice de combinação de lipoproteínas e a variação do índice de perfusão periférica entre 90 e 120 segundos após um estímulo vasodilatador endotélio-dependente (ΔIPP90-120) na predição de aterosclerose. A significância estatística foi estabelecida em p < 0,05. Resultados A amostra foi composta por 298 indivíduos com idade média de 63,0 ± 16,1 anos, dos quais 57,4% eram mulheres. Comparações pareadas da análise curva ROC dos índices que alcançaram área sob a curva (ASC) > 0,6 mostram que ΔIPP90-120 e IAP foram superiores aos demais índices, sem diferenças observadas entre si (diferença entre ASC = 0,056; IC95% -0,003-0,115). Ademais, tanto a ΔIPP90-120 [odds ratio (OR) 9,58; IC95% 4,71-19,46] quanto o IAP (OR 5,35; IC95% 2,30-12,45) foram preditores independentes de aterosclerose clínica. Conclusões O IAP e ΔIPP90-120 apresentaram melhor acurácia para discriminar aterosclerose clínica. Além disso, foram preditores independentes de aterosclerose clínica, evidenciando uma possibilidade promissora para o desenvolvimento de estratégias preventivas e de controle para doenças cardiovasculares. Tratam-se, portanto, de marcadores adequados para estudos multicêntricos do ponto de vista de praticidade, custo e validade externa.

Abstract Background The search for clinically useful methods to assess atherosclerotic diseases (ASCVD) with good accuracy, low cost, non-invasiveness, and easy handling has been stimulated for years. Thus, the atherogenic indices evaluated in this study may fit this growing demand. Objectives To assess the potential of atherogenic indices to evaluate patients with clinical atherosclerosis. Methods Single-center cross-sectional study, through which the Castelli I and II indices, the atherogenic index of plasma (AIP), the lipoprotein combine index, and the variation in the peripheral perfusion index between 90 and 120 seconds after an endothelium-dependent (ΔPI90-120) vasodilator stimulus were evaluated in the prediction of atherosclerosis. Statistical significance was set at p < 0.05. Results The sample consisted of 298 individuals with an average age of 63.0±16.1 years, of which 57.4% were women. Paired comparisons of the ROC curve analysis of the indices that reached the area under the curve (AUC) > 0.6 show that ΔPI90-120 and AIP were superior to other indices, and no differences were observed between them (difference between AUC = 0.056; 95%CI -0.003-0.115). Furthermore, both the ΔPI90-120 [odds ratio (OR) 9.58; 95%CI 4.71-19.46)] and AIP (OR 5.35; 95%CI 2.30-12.45) were independent predictors of clinical atherosclerosis. Conclusions The AIP and ΔPI90-120 represented better accuracy in discriminating clinical ASCVD. Moreover, they were independent predictors of clinical ASCVD, evidencing a promising possibility for developing preventive and control strategies for cardiovascular diseases. Therefore, they are markers for multicenter studies from the point of view of practicality, low cost, and external validity.

Relationship between peripheral ischemic microvascular reserve, persistent hyperlactatemia, and its temporal dynamics in sepsis: a post hoc study / Relação entre reserva microvascular isquêmica periférica, hiperlactatemia persistente e sua dinâmica temporal na sepse: um estudo post hoc

ABSTRACT Objective: To measure the prognostic value of peripheral ischemic microvascular reserve in the context of persistent sepsis-induced hyperlactatemia and measure its influence on the temporal dynamics of lactate and the strength of association between these variables. Methods: This post hoc analysis of the peripheral perfusion index/postocclusive reactive hyperemia trial, an observational cohort study that enrolled patients with sepsis who persisted with lactate levels ≥ 2mmol/L after fluid resuscitation (with or without shock). Peripheral ischemic microvascular reserve was evaluated using the association of the peripheral perfusion index and postocclusive reactive hyperemia techniques. The cutoff point of ∆ peripheral perfusion index peak values (%) defined the groups with low (≤ 62%) and high peripheral ischemic microvascular reserve (> 62%). Results: A total of 108 consecutive patients with persistent sepsis-induced hyperlactatemia were studied. The high peripheral ischemic microvascular reserve group showed higher 28-day mortality than the low peripheral ischemic microvascular reserve group (p < 0.01). The temporal dynamics of lactate within the first 48 hours showed a rapid decrease in lactate levels in the low peripheral ischemic microvascular reserve group (p < 0.01). However, this result was not reproduced in the linear mixed effects model. A weak correlation between peripheral ischemic microvascular reserve (%) and lactate level (mmol/L) was observed within the first 24 hours (r = 0.23; p < 0.05). Conclusion: The prognostic value of high peripheral ischemic microvascular reserve was confirmed in the context of persistent sepsis-induced hyperlactatemia. Although there was a weak positive correlation between peripheral ischemic microvascular reserve value and lactate level within the first 24 hours of sepsis diagnosis, the low peripheral ischemic microvascular reserve group appeared to have a faster decrease in lactate over the 48 hours of follow-up.

RESUMO Objetivo: Avaliar o valor prognóstico da reserva microvascular isquêmica periférica no contexto da hiperlactatemia persistente induzida pela sepse, determinar sua influência na dinâmica temporal de lactato e analisar a força da associação entre essas variáveis. Métodos: Análise post hoc do estudo de índice de perfusão periférica/hiperemia reativa pós-oclusiva caracterizada por uma coorte observacional que incluiu pacientes com sepse que persistiram com níveis de lactato ≥ 2mmol/L após a ressuscitação volêmica (com ou sem choque). A reserva microvascular isquêmica periférica foi mensurada utilizando-se a associação dos métodos do índice de perfusão periférica e hiperemia reativa pós-oclusiva. O ponto de corte dos valores da ∆ índice de perfusão periférica de pico (%) definiu os grupos com baixa (≤ 62%) e alta (> 62%) reserva microvascular isquêmica periférica. Resultados: Estudaram-se 108 pacientes consecutivos com hiperlactatemia persistente induzida pela sepse. O grupo com alta reserva microvascular isquêmica periférica apresentou maior mortalidade aos 28 dias em relação ao grupo com baixa reserva microvascular isquêmica periférica (p < 0,01). A dinâmica temporal de lactato nas primeiras 48 horas mostrou redução rápida dos níveis de lactato no grupo com baixa reserva microvascular isquêmica periférica (p < 0,01). No entanto, esse resultado não foi reproduzido no modelo de efeitos mistos lineares. Observou-se fraca correlação (%) entre os valores da reserva microvascular isquêmica periférica e níveis de lactato (mmol/L) nas primeiras 24 horas (r = 0,23; p < 0,05). Conclusão: O valor prognóstico da alta reserva microvascular isquêmica periférica foi confirmado no contexto da hiperlactatemia persistente induzida por sepse. Embora tenha sido observada uma baixa correlação positiva entre os valores da reserva microvascular isquêmica periférica e os níveis de lactato nas primeiras 24 horas do diagnóstico de sepse, o grupo com baixa reserva microvascular isquêmica periférica pareceu apresentar redução mais rápida do lactato nas 48 horas de seguimento.

Changes of peripheral perfusion index in very low birth weight infants with late-onset sepsis / 中国小儿急救医学

Objective:To analyze the changes of peripheral perfusion index (PPI) with late-onset sepsis (LOS) in very low birth weight infants during hospitalization.Methods:Very low birth weight infants admitted to the neonatal intensive care unit of Children′s Hospital of Fudan University from August 1, 2021 to August 31, 2022 were consecutively included.Infants with admission age ≥three days and unstable circulation, or positive blood culture within three days after birth were excluded.From the day of admission, the PPI values of the right hand and either foot of the infants were measured with Masimo SET Radical-7 everyday while whether LOS occurred during hospitalization was observed.The mean PPI curve of very and extremely low birth weight infants without LOS was plotted.For those with LOS confirmed by blood culture, the PPI change trajectory three days before and after the occurrence of LOS was drawn, and the change trend of PPI before the occurrence of LOS was analyzed by trend chi-square test.Non-parametric test was used to analyze the effect of LOS on pre- and post-ductal PPI values.Results:A total of 107 very low birth weight infants were included in the final analysis.Among them, there were 11 infants confirmed as LOS by blood culture, 37 infants diagnosed as clinical LOS, and 59 infants without LOS.Pre-and post-ductal PPI values of very low birth weight infants without LOS were 2.06±1.30 and 1.72±0.92, respectively; those with clinical LOS were 1.90±0.94 and 1.58±0.83, respectively; those with LOS confirmed by blood culture were 1.92±1.11 and 1.62±0.82, respectively.For infants with LOS confirmed by blood culture, the pre-and post-ductal PPI values showed a continuous downward trend during three days before the onset of disease, with the lowest PPI values on the first day before the diagnosis of blood culture.The downtrend of pre-ductal PPI was statistically significant ( χtrend2=5.57, P<0.05). Conclusion:The PPI value of very low birth weight infants show a downward trend when LOS occurs.It should be observed dynamically in clinical practice, which is helpful to suspect or identify LOS as early as possible.

O valor prognóstico da reserva microvascular isquêmica periférica na sepse não está vinculado ao peptídeo relacionado ao gene da calcitonina ou à substância P / The prognostic value of peripheral ischemic microvascular reserve in sepsis is not related to calcitonin gene-related peptide or substance P

RESUMO Objetivo: Avaliar possíveis mecanismos atribuídos ao valor prognóstico da reserva microvascular isquêmica periférica em pacientes com sepse. Métodos: Este estudo de coorte observacional incluiu 46 pacientes consecutivos com sepse em uma unidade de terapia intensiva entre novembro de 2020 e outubro de 2021. Após a ressuscitação volêmica com fluidos, avaliou-se a reserva microvascular isquêmica periférica mediante a associação dos testes hiperemia reativa pós-oclusão e índice de perfusão periférica. Adicionalmente, amostras de sangue venoso periférico foram coletadas para avaliar os níveis dos neuropeptídeos substância P e peptídeo relacionado ao gene da calcitonina no membro superior do paciente antes e imediatamente após o teste de hiperemia reativa pós-oclusão. Resultados: Não houve correlação estatisticamente significativa (p > 0,05) entre os valores basais ou variações dos níveis de neuropeptídeos e a reserva microvascular isquêmica periférica. Conclusão: Embora o peptídeo relacionado ao gene da calcitonina e a substância P possam desempenhar papel prognóstico na sepse, esses neuropeptídeos não parecem contribuir para a reserva microvascular isquêmica periférica.

ABSTRACT Objective: To evaluate the mechanisms attributed to the prognostic value of peripheral ischemic microvascular reserve in patients with sepsis. Methods: This observational cohort study enrolled 46 consecutive septic patients in the intensive care unit between November 2020 and October 2021. After fluid resuscitation, the peripheral ischemic microvascular reserve was evaluated using the association of postocclusion reactive hyperemia with the peripheral perfusion index. Additionally, peripheral venous blood samples were used to evaluate the neuropeptide calcitonin gene-related peptide and substance P levels in the upper limb before and immediately after postocclusion reactive hyperemia Results: There was no statistically significant correlation (p > 0.05) between basal values (pg/mL) or variations from neuropeptide levels (%) and the peripheral ischemic microvascular reserve (%). Conclusion: Although calcitonin gene-related peptide and substance P may have a prognostic role in sepsis, these neuropeptides do not appear to contribute to peripheral ischemic microvascular reserve.

Correlation between perfusion index and the severity of disease in early neonates / 中国小儿急救医学

Objective:To analyze the role of perfusion index(PI)in assessing the severity of neonatal illnesses.Methods:A total of 502 newborns admitted to the Department of Neonatology within 24 hours of birth at Xinxiang Central Hospital from October 2018 to July 2019 were recruited.Neonatal critical illness score(NCIS)was graded within 24 hours of admission, and newborns were categorized into non-critical(NCIS>90 scores), critical(NCIS 70-90 scores)and extremely critical(NCIS<70 scores). PI was monitored in all newborns within 24 hours of birth in a resting state.A total of 502 PIs were recorded, including 341 cases of non-critical, 110 cases of critical and 51 cases of extremely critical.Results:The medium PI [ M( P25, P75)] of newborns in non-critical, critical and extremely critical groups were 1.80(1.40, 2.60), 0.96(0.74, 1.43)and 0.65(0.41, 1.10), respectively.PI values in extremely critical group was significantly lower than those in critical group and non-critical group( P<0.05). The medium PI [ M( P25, P75)] of full-term newborns, moderate/late preterm newborns and extremely/very preterm newborns were 1.70(1.20, 2.70), 1.60(1.10, 2.30) and 1.35(0.80, 2.30), respectively.PI in full-term newborns was significantly higher than those in moderate/late preterm newborns and extremely/very preterm newborns( P<0.05). PI was moderately positively correlated with NCIS in newborns( r=0.791, P<0.01). The area under the receiver operating characteristic curve of NCIS predicted by PI value was 0.846, and the prediction sensitivity and specificity were 85.0% and 70.8% when PI was 0.56. Conclusion:PI is correlated with NCIS in newborns, which is able to reflect the severity of neonatal illnesses.A low PI indicates severe conditions of neonatal illnesses.

The prognostic value of PI combined with Pv-aCO 2 /Ca-vO 2 in patients with septic shock / 中华急诊医学杂志

Objective:To explore the predictive value of peripheral perfusion index (PI) combined with central venous-arterial carbon dioxide tension to arterial-venous oxygen content ratio(Pv-aCO 2/Ca-vO 2)for prognosis after initial resuscitation of septic shock. Methods:A total of 76 cases of patients with septic shock from January 2019 to January 2021 in emergency intensive care unit (EICU) of Harrson international peace hospital affiliated to Hebei Medical University were enrolled. All recovered according to 2016 Severe Sepsis and Septic Shock Treatment International Guidelines 2016 (SSC 2016) , and PI was monitored, central vein and arterial blood gas analysis was performed, and the ratio of Pv-aCO 2/Ca-vO 2 was calculated.The PI and Pv-aCO 2/Ca-vO 2 at 3 h,hemodynamic variables,oxygen metabolism indexes,APACHEⅡ and SOFA score were recorded.Patients were divided into survival group and death group according to 28 d survival condition, the dfferences in demographics and clinical data were compared between two groups.The Kaplan-Meier urviving curve was created and the survival of the patients was analyzed by the Log-rank test. Risk factors associated with the prognosis were analyzed using the Cox regression analysis. The role of PI and Pv-aCO 2/Ca-vO 2 in prediting death was evaluated by receiver operating characteristic curves(ROC). Results:There were 37 cases in survival group and 39 cases in death group.Compared with death group, PI in survival group [(1.77±0.63) vs. (0.89±0.69)]was significantly higher,and Pv-aCO 2/Ca-vO 2[(1.52±0.52) vs. (2.57±0.86)] was significantly lower ( P<0.05). Kaplan-Meier survival curve showed that the median survival time in the high PI group [20.09 d (95% CI:16.95-23.24) vs.11.00d (95% CI:7.14-14.86)] was longer than that in the low PI group(χ 2=12.424, P=0.000),and that in low Pv-aCO 2/Ca-vO 2 group [23.74 d (95% CI:20.35-27.13) vs.12.85d (95% CI:9.75-15.95)] was longer than that in the high Pv-aCO 2/Ca-vO 2 group (χ 2=12.200, P=0.000) .Cox regression analysis showed that both PI ( RR=0.397, 95% CI: 0.230-0.687, P =0.001) and Pv-aCO 2/Ca-vO 2 ( RR=1.878, 95% CI: 1.169-3.019, P =0.009) were predictors of 28 d mortality.The area under the ROC curve of PI and Pv-aCO 2/Ca-vO 2 for predicting 28 d death in patients with septic shock were 0.828 (95% CI: 0.732-0.923) and 0.785 (95% CI: 0.6777-0.893)respectively. The optimal cutoff values were 0.52 (sensitivity 58.3% and specificity 94.4%) and 0.35 (sensitivity 88.9% and specificity 63.9%)respectively, and the AUC of the combined prediction of the two indicators was 0.903 (95% CI: 0.835-0.971). Conclusions:Combination of PI and Pv-aCO 2/Ca-vO 2 is better to predict the risk of adverse outcomes of septie shock patients,and may provide useful information for the resuscitation at early stage.

Study on the value of pulse oximetry plethysmographic waveform derived parameters on the quality of cardiopulmonary resuscitation / 中华急诊医学杂志

Objective:Pulse oximetry plethysmographic (POP) waveform to indicate the patient's perfusion status and the quality of resuscitation has been affirmed. The POP waveform is obtained by a non-invasive monitoring method, and its clinical feasibility during CPR is better than that of invasive monitoring technologies. This study aimed to analyze the three parameters derived from POP waveform: CPR quality index (CQI), perfusion index (PI), and chest compression fraction (CCF) in evaluating the CPR quality and ROSC possibility.Methods:A prospective descriptive study was conducted on 74 CPR patients who were divided into the ROSC group and non-ROSC group according to their resuscitation results. The clinical data were extracted from patient monitor, the distribution and changes of the three parameters during CPR were collected, and their value of evaluating resuscitation outcome were analyzed.Results:At the end stage of resuscitation, there were statistically significant differences in the three parameters between the two groups ( P<0.05). In addition, CQI was significantly more capable in evaluating the possibility of ROSC than PI and CCF ( P<0.05). Conclusions:CQI, PI and CCF derived from POP waveform can all be applied to evaluate CPR quality and ROSC possibility. CQI has higher prognosis value than PI and CCF.

The correlation between carotid blood flow and the parameters derived by pulse oximetry plethysmographic waveform during cardiopulmonary resuscitation in a porcine model / 中华急诊医学杂志

Objective:To explore the correlation between carotid blood flow and the parameters derived by pulse oximetry Plethysmographic waveform in cardiopulmonary resuscitation, so as to provide a new index for carotid blood flow monitoring in cardiopulmonary resuscitation.Methods:Seven male domestic pigs were utilized for cardiac arrest model through ventricular fibrillation induced by electrical stimulation. Eight minutes after cardiac arrest, artificial chest compression was given for 4 min, and epinephrine 20 μg/kg was injected intravenously at 2 min after chest compression. The compression frequency, compression depth, right carotid blood flow, pulse oximetry plethysmographic waveform, aortic pressure, right atrium pressure and end tidal carbon dioxide partial pressure were continuously monitored and recorded. From 30 s to 4 min after chest compression, the values of the mean right carotid blood flow, the area under curve (AUC) of pulse oximetry plethysmographic waveform, the mean perfusion index, the mean coronary perfusion pressure and the average end-tidal carbon dioxide partial pressure during 6 s before time point were calculated every 30 s. The correlations between right carotid blood flow and the AUC of pulse oximetry plethysmographic waveform and perfusion index were analyzed respectively.Results:Ventricular fibrillation was induced successfully in seven animals. There were no significant differences in the mean chest compression frequency and depth per min during 4 min of chest compression. Right carotid blood flow at 30 s after chest compression was (92.7±32.7) mL/min, and decreased to (48.5±23.5) mL/min at 1 min after chest compression ( P<0.05). There was no significant difference in blood flow before and after epinephrine injection ( P>0.05). The AUC of the blood oxygen plethysmographic waveform and perfusion index showed synchronous change trends with right carotid blood flow. Both coronary perfusion pressure and end-tidal carbon dioxide partial pressure showed different change trends with right carotid blood flow. There was a positive correlation between the right carotid blood flow and the AUC of blood oxygen plethysmographic waveform ( r=0.66, P<0.01), and also a positive correlation between right carotid blood flow and perfusion index ( r=0.57, P<0.01). Conclusions:Carotid blood flow is positively correlated with the AUC of blood oxygen plethysmographic waveform and perfusion index in a porcine model of cardiopulmonary resuscitation. Real-time monitoring of the two parameters derived by pulse oximetry plethysmographic waveform can reflect the changes of carotid blood flow to a certain extent.

The role of the perfusion index in patients with thoracic trauma / 世界急诊医学杂志（英文）

@#Traumatic injuries range from simple to complicated multiple injuries. The identification of patients with critical injuries and disrupted organ perfusion is essential to prevent tissue hypoxia. A study estimated that a fast and accurate response to thoracic trauma should reduce the mortality by 30%.[1] The tissue perfusion value is an essential indicator of mortality and morbidity for patients admitted to the hospital with thoracic trauma. Thus, this study aimed to show the role of the perfusion index (PI) in predicting the prognosis of patients admitted to the emergency department for thoracic trauma.

Clinical study of fluid resuscitation guided by peripheral perfusion index in patients with septic shock / 中华危重病急救医学

Objective:To explore the guiding effect of peripheral perfusion index (PI) on fluid resuscitation in patients with septic shock.Methods:Sixty-five patients with septic shock who were diagnosed according to relevant criteria of septic shock and admitted to the department of critical care medicine of the Affiliated Hospital of Hangzhou Normal University from September 2017 to December 2020 were included. Patients were divided into the conventional treatment group (30 cases) and PI guidance group (35 cases) by random number method. Both groups of patients were treated with the bundle according to clinical guidelines. Sputum, urine and blood were collected for pathogenic microorganism culture before the application of antibiotics, and vasoactive drugs were given. Both groups need to achieve all the following resuscitation goals within 6 hours: urine output > 0.5 mL·kg -1·h -1, mean arterial pressure (MAP) ≥ 65 mmHg (1 mmHg ≈ 0.133 kPa), central venous pressure (CVP) was 8-12 mmHg, and central venous oxygen saturation (ScvO 2) ≥ 0.70. There was no further resuscitation in the conventional treatment group after the goals were achieved. In addition to these four goals, the PI guidance group was expected to achieve PI≥ 1.4. Heart rate (HR), CVP, MAP, ScvO 2, blood lactic acid (Lac), the time of fluid negative balance, intensive care unit (ICU) mortality and 28-day mortality between the two groups were compared before and after 6 hours of fluid resuscitation. Results:Before fluid resuscitation, there were no statistically significant differences in all indicators between two groups. After 6 hours fluid resuscitation, the four treatment goals in PI guidance group were slightly lower than those of the conventional treatment group [HR (times/min): 96.5±12.1 vs. 97.7±7.9, MAP (mmHg): 83.2±6.2 vs. 82.1±7.5, ScvO 2: 0.661±0.077 vs. 0.649±0.051, CVP (mmHg): 10.8±2.7 vs. 10.4±2.1], there were no statistically significant differences between the two groups (all P > 0.05); the Lac level of the PI guidance group after resuscitation was lower than that of the conventional treatment group, and the difference was statistically significant (mmol/L: 4.8±1.3 vs. 5.9±1.4, P < 0.05); the duration of fluid negative balance in the PI guidance group was earlier than that in the conventional treatment group [days: 3.0 (2.0, 3.0) vs. 3.5 (3.0, 4.0), P < 0.05]. The ICU mortality and 28-day mortality in the PI guidance group were lower than those in the conventional treatment group [ICU mortality rate: 37.1% (13/35) vs. 50.0% (15/30), 28-day mortality rate: 57.1% (20/35) vs. 60.0% (18/30)], but the differences were not statistically significant (both P > 0.05). Conclusions:The peripheral PI can be used as an important indicator of fluid resuscitation in patients with septic shock. PI guiding fluid resuscitation in patients with septic shock can reduce Lac levels, shorten the duration of fluid negative balance and reduce the risk of fluid overload.

Application of peripheral perfusion index in the screening of congenital heart disease in neonates / 中国小儿急救医学

Congenital heart disease (CHD) is the most common congenital malformations, and critical CHD is one of the main causes of neonatal death and poor prognosis.Early screening and detection of congenital heart disease in newborns is helpful to early intervention and improve prognosis.At present, pulse oximetry alone, pulse oximetry combined with physical examination or pulse oximetry combined with cardiac murmur auscultation in early postnatal screening can detect most of critical CHD, but there are still some false negative results.Peripheral perfusion index (PPI) may have a certain value in finding left ventricular obstructive CHD that can not be found in the current screening methods.Therefore, this review summarized the technical principle and influence factors of PPI, its feasibility and effectiveness in neonatal CHD screening, and the possible threshold of screening, in order to provide a certain basis for PPI screening of neonatal CHD in the future.

Perfusion index: Could this be a new triage tool for upper gastrointestinal system bleeding in the emergency department? A prospective cohort study

ABSTRACT BACKGROUND: Many scoring systems for predicting mortality, rebleeding and transfusion needs among patients with upper gastrointestinal bleeding (UGIB) have been developed. However, no scoring system can predict all these outcomes. OBJECTIVE: To show whether the perfusion index (PI), compared with the Rockall score (RS), helps predict transfusion needs and prognoses among patients presenting with UGIB in emergency departments. In this way, critical patients with transfusion needs can be identified at an early stage. DESIGN AND SETTING: Prospective cohort study in an emergency department in Turkey, conducted between June 2018 and June 2019. METHODS: Patients' demographic parameters, PI, RS, transfusion needs and prognosis were recorded. RESULTS: A total of 219 patients were included. Blood transfusion was performed in 174 patients (79.4%). The PI cutoff value for prediction of the need for blood transfusion was 1.17, and the RS cutoff value was 5. The area under the curve (AUC) value for PI (AUC: 0.772; 95% confidence interval, CI: 0.705-0.838; P < 0.001) was higher than for RS (AUC: 0.648; 95% CI: 0.554-0.741; P = 0.002). 185 patients (84.5%) were discharged, and 34 patients (15.5%) died. The PI cutoff value for predicting mortality was 1.1, and the RS cutoff value was 7. The AUC value for PI (AUC: 0.743; 95% CI: 0.649-0.837; P < 0.001) was higher than for RS (AUC: 0.725; 95% CI: 0.639-0.811; P < 0.001). CONCLUSION: PI values for patients admitted to emergency departments with UGIB on admission can help predict their need for transfusion and mortality risk.

Correlación del índice de perfusión con la repercusión del conducto arterioso en prematuros / Correlation of perfusion index with patent ductus arteriosus repercussion in premature newborns

Resumen Antecedentes: El conducto arterioso es una estructura necesaria en la circulación fetal, su persistencia puede provocar alteraciones hemodinámicas. El estándar de oro diagnóstico es la ecocardiografía, no siempre disponible. Las unidades de cuidados intensivos neonatales (UCIN) cuentan con oximetría de pulso, que mide el índice de perfusión (IP), el cual podría funcionar como auxiliar en el diagnóstico de persistencia del conducto arterioso hemodinámicamente significativo (PCAHs). Objetivo: Correlacionar el incremento del índice de perfusión (ΔIP) a las 24 y 72 h de vida extrauterina con PCAHs en recién nacidos prematuros de la UCIN de un hospital de segundo nivel. Material y métodos: Estudio de cohorte analítico prospectivo donde se incluyeron neonatos de 26 a 34 semanas de gestación, sin comorbilidades, a quienes se les realizó ecocardiograma y medición de IP en brazo y pierna a las 24 y 72 h. Se efectuó análisis bivariante con Y2/prueba exacta de Fisher y t de Student/U de Mann-Whitney, además correlación de Spearman y regresión lineal para predicción de valores. Resultados: Se incluyeron 39 prematuros. No se encontró diferencia significativa entre los pacientes sin y con PCAHs (mediana: 0.22 [0.06, 0.58] vs. 0.03 [–0.27, 0.2]; p = 0.09) a las 24 h de vida y tampoco a las 72 h de vida (mediana: 0.2 [0, 0.47] vs. 0.45 [–0.37, 0.76], p = 0.47). Se encontró una correlación positiva entre el diámetro del conducto arterioso (DCA) y el ΔIP (r: 0.78; IC 95%: 0.60-0.88; p = 0.01). La fórmula de predicción por regresión lineal se expresa así: DCA = 1.31 + (2.05 x ΔIP). Conclusiones: El IP no permite discriminar entre pacientes sin y con PCAHs. El ΔIP podría ser una herramienta para la monitorización del diámetro del conducto en neonatos después de las 72 h de vida.

Abstract Background: The ductus arteriosus is a necessary structure in fetal circulation, and its patency can produce hemodynamic alterations. The diagnostic gold standard is echocardiography, not always available. In the neonatal intensive care unit (NICU) they have pulse oximetry that measures perfusion index (PI), which could be used as a diagnostic tool in hemodynamic significant patent ductus arteriosus (HSPDA). Objective: To correlate the perfusion index increment (ΔPI) in 24 and 72 h after birth with HSPDA in premature newborns of NICU in a second level hospital. Materials and methods: This is an analytic prospective study which included neonates of 26-34 weeks of gestational age, without comorbidities, who underwent echocardiography and measurement of PI in arm and leg, 24 and 72 h after birth. We did bivariate analysis with Y2/exact Fisher test and Student t-test/Mann-Whitney U test, besides Spearman correlation and linear regression for value prediction. Results: We included 39 premature newborns. We did not find significant differences between patients without and with HSPDA (Median: 0.22 [0.06-0.58] vs. 0.03 [–0.27-0.2]; p = 0.09) at 24 h neither 72 h after birth (Median: 0.2 [0-0.47] vs. 0.45 [–0.37-0.76]; p = 0.47). We found a positive correlation between ductus arteriosus diameter (DAD) and ΔPI (r: 0.78; CI 95%: 0.6-0.88; p = 0.01). The prediction formula with linear regression is expressed this way: DAD = 1.31 + (2.05 x ΔIP). Conclusions: The PI doesn´t allow us to discriminate between patient without and with HSPDA. The ΔPI could be a tool for the monitorization of DAD in neonates 72 h after birth.

Prediction Of Successful Supraclavicular Brachial Plexus Block Using Pulse Oximeter Perfusion Index

Background and goals:Supraclavicular approach to brachial plexus block is a popular approach for anaesthesia for upper limb surgeries. Conventional methods for evaluation of block success are time consuming. The aim of this study is to evaluate whether the change in perfusion index (PI) can be used to predict the ultrasound-guided supraclavicular nerve block success.Methodology: The study was performed after written informed consent from 32 ASA PS I, II patients scheduled for elective hand, wrist and forearm surgery under ultrasound-guided supraclavicular nerve block. After local anaesthetic injection, sensory block success and motor block success was assessed every 5min.The PI was recorded at baseline and at 10, 20min after anaesthetic injection in both blocked and non-blocked limbs. The PI ratio was calculated as the PI after 20min divided by the PI at the baseline.Results:Baseline values of PI ranged from 0.2 to 3.42 in 32 patients for whom supraclavicular block was performed. At 10 min, percentage increase of PI was (mean ± standard deviation) 484.38 ± 295.80 % from baseline. At 20 min, percentage increase of PI was 557.31 ± 239.25 % from baseline. All changes from baseline were significant (p < 0.01) Conclusion: Perfusion index monitoring may provide a highly valuable tool to evaluate the success of regional anaesthesia of the upper extremity in clinical practice.

Development of a Portable Pulse Oxymetry Simulator System / 中国医疗器械杂志

This article describes the design of a portable blood oxygen simulation system that can be used to simulate various blood gas saturation states of the human body. The system can be used to simulate various states of blood gas saturation, and can also simulate large blood oxygen saturation dynamic range, pulse rate range and perfusion index range. It can be used for testing, but not for clinical examination instruments. Moreover, the system has the characteristics of small size and low cost compared with the commercial blood oxygen simulator. Although the simulation system is not directly used for the detection of blood gas saturation of patients, it is also an essential equipment in the production and testing process, so it has certain practical value.

Effects of two different anesthesia methods on temperature, perfusion index and coagulation function / 中国基层医药

Objective@#To observe the effects of general anesthesia and intravertebral anesthesia on the patients' temperature, perfusion index(PI) and coagulation function.@*Methods@#From January 2016 to December 2017, 60 patients in the First Hospital of Jiaxing undergoing elective line of great saphenous varicose veins surgery were selected.According to the random number table, the patients were divided into the general anesthesia group(group G, n=30) and intraspinal anesthesia group(group I, n=30). The general condition, operation time, the core temperature(tympanic membrane temperature) before anesthesia(T0), 10 min after anesthesia(T1), 20 min later(T2), 30 min later(T3), and the PI with no-infusion upper limb were recorded.The changes of coagulation function before anesthesia(T0) and after surgery(T4) were observed by extraction of the thrombus(TEG).@*Results@#The core body temperature of T1, T2 and T3 was significantly decreased in both two groups(FG=58.789, P=0.000, FI=2.965, P=0.035), and the hypothermia of group G was greater than that of group I(t1=-2.998, t2=-5.985, t3=-7.705; P<0.05). The PI of T1, T2 and T3 was significantly higher than T0 in both two groups(FG=5.439, P=0.002, FI=3.404 P=0.020), and the increase of group G was greater than that of group I(t1=2.065, t2=2.041, t3=2.649; P<0.05). In group G, TEG examination was significantly prolonged(F=5.482, P=0.023), and no significant changes were observed in group I.@*Conclusion@#The hypothermia of the patients and the increase of PI increased significantly, and the R time index of TEG is prolonged, and the anesthesia in the spinal canal has no obvious effect on the coagulation function.

Uso do índice de perfusão para avaliar reatividade microvascular no choque séptico após ressuscitação volêmica / Perfusion index for assessing microvascular reactivity in septic shock after fluid resuscitation

RESUMO Objetivo: Os distúrbios microcirculatórios estão implicados no prognóstico do choque séptico. A hiporresponsividade microvascular pode ser avaliada por meio do índice de perfusão, derivado da oximetria de pulso e hiperemia reativa. Com utilização do índice de perfusão, investigamos a hiperemia reativa e sua relação com a perfusão periférica e os parâmetros clínico-hemodinâmicos no choque séptico. Métodos: Avaliaram-se 82 pacientes, 47 deles com choque séptico e 35 controles. Os exames foram realizados dentro de 24 horas após a admissão. O índice de perfusão foi avaliado antes e após uma oclusão do fluxo sanguíneo durante 3 minutos, utilizando-se análise de resposta temporal por 5 minutos. O índice de perfusão foi também avaliado nas fases hiperêmicas, principalmente com derivação de mecanismos mecanossensitivos (ΔIP0-60) e metabólicos (ΔIP60-120). Realizaram-se testes de correlação entre a hiperemia reativa e dados clínicos hemodinâmicos. Resultados: A hiperemia reativa, medida pelo índice de perfusão, foi significantemente mais baixa no choque séptico apenas até 45 segundos após a desinflação do manguito. No período restante, não houve diferenças estatisticamente significantes entre os grupos. Os picos de índice de perfusão foram similares entre os grupos, embora o pico tenha sido atingido de forma mais lenta no grupo séptico. Os valores de ΔIP0-60 foram mais baixos no choque [1% (-19% - -40%) versus 39% (6% - 75%); p = 0,001]. No entanto, o ΔIP60-120 foi similar entre os grupos [43% (18% - 93%) versus 48% (18% - 98%); p = 0,58]. O tempo até o pico do índice de perfusão se correlacionou de forma positiva com o SOFA e negativamente com os níveis de proteína C-reativa. O pico de índice de perfusão se correlacionou de forma positiva com as doses de vasopressores; os valores de ΔIP60-120 tiveram correlação positiva com o nível de proteína C-reativa e as doses de vasopressores. Não ocorreram outras correlações significantes. Conclusões: Este estudo com base no índice de perfusão sugere que o choque séptico promove hiporresponsividade vascular periférica, enquanto a reatividade vascular posterior é consideravelmente preservada. Estes resultados demonstram resposta hiperêmica periférica dependente do tempo e significante reserva isquêmica no choque séptico.

ABSTRACT Objective: Microcirculation disturbances are implicated in the prognosis of septic shock. Microvascular hyporesponsiveness can be assessed by an oximetry-derived perfusion index and reactive hyperemia. Using this perfusion index, we investigated reactive hyperemia and its relationship with peripheral perfusion and clinical-hemodynamic parameters in septic shock. Methods: Eighty-two patients were evaluated: 47 with septic shock and 35 controls. Tests were performed within 24 hours after admission. The perfusion index was evaluated before and after a 3-min blood flow occlusion using a time-response analysis for 5 min. The perfusion index was also evaluated in the hyperemic phases and was mainly derived by mechanosensitive (ΔPI0-60) and metabolic mechanisms (ΔPI60-120). Correlation tests were performed between reactive hyperemia and clinical-hemodynamic data. Results: Reactive hyperemia measured by the perfusion index was significantly lower in patients with septic shock, but this was only observed for the first 45 seconds after cuff-deflation. In the remaining period, there were no statistical differences between the groups. The peaks in the perfusion index were similar between groups, although the peak was reached more slowly in the septic group. Values of ΔPI0-60 were lower in shock [01% (-19% - -40%) versus 39% (6% - 75%); p = 0.001]. However, ΔPI60-120 was similar between the groups [43% (18% - 93%) versus 48% (18% - 98%); p = 0.58]. The time-to-peak of the perfusion index was correlated positively with the SOFA scores and negatively with C-reactive protein; the peak of the perfusion index was positively correlated with vasopressor doses; and the ΔPI60-120 values were positively correlated with C-reactive protein and vasopressor doses. No other significant correlations occurred. Conclusions: This perfusion index-based study suggests that septic shock promotes initial peripheral vascular hyporesponsiveness and preserves posterior vascular reactivity to a considerable degree. These results demonstrate a time-dependent peripheral hyperemic response and a significant ischemic reserve in septic shock.

The role of physical examination, pulse oximetry screening, and perfusion index in screening of neonatal congenital heart disease / 临床儿科杂志

Objective To find a reliable, simple, and easily-operated method for the screening of neonatal congenital heart disease (CHD). Methods A total of 7 105 neonates born from January 2017 to July 2017 were selected. The validity and reliability of physical examination, pulse oximetry screening (POS), and perfusion index (PI) in the screening of neonatal CHD were evaluated according to the diagnosis made by color Doppler echocardiography. Results When physical examination, POS or PI was used separately in screening for CHD, the sensitivities were in the range of 13.11%~73.77%, specificities 50.20%~99.34%, Youden indexes 0.12~0.70, the total coincidence rates 50.40%~98.86%, positive predictive values 1.27%~40.70%, and negative predictive values 99.29%~99.70%. When physical examination, POS and PI were combined (two or three indexes were positive) for screening, the sensitivities and Youden indexes were 85.25% and 0.82 respectively, which were higher than those of single indicators and suggested that the combination had higher authenticities. The total coincidence rate of the combination was 97.07%, and, although it was lower than POS group (98.86%) and PI screening group (98.58%), it still had a good reliability. Conclusions The combination of physical examination, POS and PI has a certain clinical value in neonatal CHD screening.

Using peripheral perfusion index and venous-to-arterial CO2difference/arterial-central venous O2 difference ratio to assess lactate clearance in septic patients after resuscitation / 中华内科杂志

Objective The relationship of venous-to-arterial CO2difference(Pv-aCO2)/ arterial-central venous O2difference (Ca-vO2) ratio, peripheral perfusion index(PI) and lactate clearance(LC) were investigated during resuscitation in septic patients. And, the meaning of the combination PI and Pv-aCO2/Ca-vO2ratio to interpret incoherence of lactate clear was explored. Methods The patients with sepsis were prospectively observed, who admitted to critically care medicine department of Peking Union Medical College Hospital. The hemodynamic parameters, simultaneous arterial and central venous blood gas analysis and PI were obtained at the enrollment (T0) and 8 hours (T8) during resuscitation. The lactate clearance was defined as 8h-LC≥10% and non-lactate clearance was defined as 8h-LC≤10%. Additionally, the patients were divided as three sub-groups according to the PI value at T8: the normalized PI group with PI≥1.4,the mild impaired PI with 1.4＜PI＜0.6 and severe impaired PI with PI≤0.6. Results A total of 84 patients were enrolled in this study. There was no significant difference in Pv-aCO2/Ca-vO2ratio in the three groups. However, the PI≤0.6 group had a significantly higher Pv-aCO2than other groups. Moreover, the patients with non-lactate clearance (13/32) had a higher Pv-aCO2/Ca-vO2ratio than the patients with lactate clearance in PI≥1.4 group (1.9±0.7 vs. 1.3±1.0, P=0.01). Multivariate analysis showed both Pv-aCO2/Ca-vO2ratio [Exp(B) 2.235,95% CI 1.232-4.055,P=0.008] and acute physiology and chronic health evaluation Ⅱ(APACHEⅡ) [Exp(B)1.087,95%CI 1.022-1.156,P=0.008] were independent risk factor of non-lactate clearance. 8h-PI was significantly negative correlated with the 8 h Pv-aCO2gap (r=-0.311, P=0.004), but not significantly with Pv-aCO2/Ca-vO2ratio (r=-0.094, P=0.385). Conclusions Both high Pv-aCO2/Ca-vO2 ratio and low PI were related to non-lactate clearance after resuscitation in sepsis. Combined PI and Pv-aCO2/Ca-vO2ratio could interpret incoherence of latacte clearance after resuscitation.

The relationship between arterial blood lactate clearance, prognosis and myocardial damage in patients with septic shock after early goal-directed therapy / 中华内科杂志

Objective To evaluate the prognostic value of arterial blood lactate clearance based on central venous oxygen saturation and perfusion index in patients with septic shock related myocardial injury after early goal-directed therapy.Methods One hundred and fifty-seven patients with septic shock after early resuscitation were enrolled from August 2013 to July 2016 in ICU at Peking Union Medical College Hospital.Parameters indicating early resuscitation included central venous pressure (CVP) 8-12 mmHg (1 mmHg=0.133 kPa),mean arterial pressure (MAP)＞65 mmHg,central venous oxygen saturation(ScvO2)＞70％ and urine volume (UO) ＞0.Sml · kg-1 · h-1 and arterial blood lactatc (Lac) ＞2 mmoL/L.Patients were divided into group A [ScvO2＞80％ and perfusion index (PI)＞1.4],group B(ScvO2＞80％ and PI＜1.4),group C (ScvO2＜80％ and PI＞1.4),group D(ScvO2＜80％ and Pl＜l.4).Hemodynamic parameters and tissue perfusion indexes at 2 hours(T2),4 hours(T4) and 6 hours(T6) after early resuscitation and troponin Ⅰ which indicated myocardial damage,on day 1 2 3 in ICU were recorded.Results (1)Lac clearance in group C was the quickest,which was 34.57％ (21.44％,44.20％),58.33％ (30.19％,70.79％),71.43％ (53.75％,82.79％) at T2,T4,T6 respectively.(2)The maximal incidence of myocardial damage was in group B(85.0％) and the lowest in group A (45.7％) on day 1 in ICU.Whereas on day 2,group C showed the lowest incidence of myocardial damage (29.3％) and group B the highest(70.0％).On day 3,the proportion of elevated troponin Ⅰ in group B was 70.0％,which was significantly higher than that of group B (29.3％,P＜0.008).(3)Logistic regression analysis suggested that the rate of Lac clearance at T4 in group B was related to the incidence of myocardial damage on day 2 and 3 in ICU.Conclusions The combination of PI and ScvO2 as a resuscitation target in patients with septic shock facilitates Lac clearance as the goal of resuscitation.The rate of arterial Lac clearance based on ScvO2 and PI is correlated with myocardial injury in patients with septic shock after early goal-directed therapy.