Impact of Persistent Pulmonary Hypertension of the Newborn in Neonates with Dextro-transposition of the Great Arteries.

Objectives: This study aimed to assess the impact of persistent pulmonary hypertension of the newborn (PPHN) on perioperative morbidity and mortality in patients with dextro-transposition of the great arteries. Secondarily, we evaluated the association between postoperative outcomes and intraoperative variables including the duration of cardiopulmonary bypass, cerebral oxygen desaturation, and hypotension.

Design: Retrospective observational study.

Impact of clinicians' behavior, an educational intervention with mandated blood pressure and the hypotension prediction index software on intraoperative hypotension: a mixed methods study.

Purpose: Intraoperative hypotension (IOH) is associated with adverse outcomes. We therefore explored beliefs regarding IOH and barriers to its treatment. Secondarily, we assessed if an educational intervention and mandated mean arterial pressure (MAP), or the implementation of the Hypotension Prediction Index-software (HPI) were associated with a reduction in IOH.

Perioperative monitoring of the oxygen reserve: where do we stand?

The Oxygen Reserve Index (ORi) is an advanced plethysmography-derived variable that may help to quantify the degree of hyperoxia in patients receiving supplemental oxygen administration. ORi is a (relative) indicator of the actual partial pressure of oxygen dissolved in arterial blood (PaO). As such, it may help in the titration of oxygen administration or it may help to warn the clinician of a deterioration of oxygen status of the patient.

Agreement of somatic and renal near-infrared spectroscopy with reference blood samples during a controlled hypoxia sequence: a healthy volunteer study.

Purpose: O3® Regional Oximetry (Masimo Corporation, California, USA) is validated for cerebral oximetry. We aimed to assess agreement of somatic and renal near-infrared spectroscopy with reference blood samples.

Methods: O3 sensors were placed bilaterally on the quadriceps and flank of 26 healthy volunteers.

Microvascular effects of oxygen and carbon dioxide measured by vascular occlusion test in healthy volunteers.

Background: Changes in near-infrared spectroscopy-derived regional tissue oxygen saturation (StO) during a vascular occlusion test (VOT; ischemic provocation of microcirculation by rapid inflation and deflation of a tourniquet) allow estimating peripheral tissue O consumption (desaturation slope; DS), vascular reactivity (recovery slope; RS) and post-ischemic hyperperfusion (AUC-H). The effects of isolated alterations in the inspiratory fraction of O (FiO) and changes in expiratory CO remain to be elucidated. Therefore, in this secondary analysis we determined the effects of standardized isolated instances of hypoxia, hyperoxia, hypocapnia and hypercapnia on the VOT-induced StO changes in healthy volunteers (n = 20) to establish reference values for future physiological studies.

What is new in microcirculation and tissue oxygenation monitoring?

Ensuring and maintaining adequate tissue oxygenation at the microcirculatory level might be considered the holy grail of optimal hemodynamic patient management. However, in clinical practice we usually focus on macro-hemodynamic variables such as blood pressure, heart rate, and sometimes cardiac output. Other macro-hemodynamic variables like pulse pressure or stroke volume variation are additionally used as markers of fluid responsiveness.

Do alterations in pulmonary vascular tone result in changes in central blood volumes? An experimental study.

Background: The effects of selective pulmonary vascular tone alterations on cardiac preload have not been previously examined. Therefore, we evaluated whether changing pulmonary vascular tone either by hypoxia or the inhalation of aerosolized prostacyclin (PGI) altered intrathoracic or pulmonary blood volume (ITBV, PBV, respectively), both as surrogate for left ventricular preload. Additionally, the mean systemic filling pressure analogue (Pmsa) and pressure for venous return (Pvr) were calculated as surrogate of right ventricular preload.

Comparison of renal region, cerebral and peripheral oxygenation for predicting postoperative renal impairment after CABG.

Patients undergoing coronary artery bypass grafting (CABG) are at risk of developing postoperative renal impairment, amongst others caused by renal ischemia and hypoxia. Intra-operative monitoring of renal region tissue oxygenation (SrtO) might be a useful tool to detect renal hypoxia and predict postoperative renal impairment. Therefore, the aim of this study was to assess the ability of intra-operative SrtO to predict postoperative renal impairment, defined as an increase of serum creatinine concentrations of  > 10% from individual baseline, and compare this with the predictive abilities of peripheral and cerebral tissue oxygenation (SptO and SctO, respectively) and renal specific tissue deoxygenation.

Cerebral oxygenation during pediatric congenital cardiac surgery and its association with outcome: a retrospective observational study.

Purpose: Non-invasive cerebral oxygen saturation (ScO) monitoring is an established tool in the intraoperative phase of pediatric congenital cardiac surgery (CCS). This study investigated the association between ScO and postoperative outcome by investigating both baseline ScO values and intraoperative desaturations from baseline.

Methods: All CCS procedures performed in the period 2010-2017 in our institution in which ScO was monitored were included in this historical cohort study.

Continuous noninvasive pulse wave analysis using finger cuff technologies for arterial blood pressure and cardiac output monitoring in perioperative and intensive care medicine: a systematic review and meta-analysis.

Background: Finger cuff technologies allow continuous noninvasive arterial blood pressure (AP) and cardiac output/index (CO/CI) monitoring.

Methods: We performed a meta-analysis of studies comparing finger cuff-derived AP and CO/CI measurements with invasive measurements in surgical or critically ill patients. We calculated overall random effects model-derived pooled estimates of the mean of the differences and of the percentage error (PE; CO/CI studies) with 95%-confidence intervals (95%-CI), pooled 95%-limits of agreement (95%-LOA), Cochran's Q and I (for heterogeneity).

Intraoperative hypotension and its prediction.

Intraoperative hypotension (IOH) very commonly accompanies general anaesthesia in patients undergoing major surgical procedures. The development of IOH is unwanted, since it is associated with adverse outcomes such as acute kidney injury and myocardial injury, stroke and mortality. Although the definition of IOH is variable, harm starts to occur below a mean arterial pressure (MAP) threshold of 65 mmHg.

Disagreement in cardiac output measurements between fourth-generation FloTrac and critical care ultrasonography in patients with circulatory shock: a prospective observational study.

Background: Cardiac output measurements may inform diagnosis and provide guidance of therapeutic interventions in patients with hemodynamic instability. The FloTrac™ algorithm uses uncalibrated arterial pressure waveform analysis to estimate cardiac output. Recently, a new version of the algorithm has been developed.

Oxygen Reserve Index: Validation of a New Variable.

Background: Pulse oximetry-derived oxygen saturation is typically >97% in normoxia and hyperoxia, limiting its clinical use. The new Oxygen Reserve Index (ORi), a relative indicator of the partial pressure of oxygen dissolved in arterial blood (PaO2) in the range of 100-200 mm Hg, may allow additional monitoring of oxygen status.

Methods: In this prospective validation intervention study, 20 healthy volunteers were breathing standardized oxygen concentrations ranging from mild hypoxia (fraction of inspired oxygen = 0.

Minimally invasive cardiac output technologies in the ICU: putting it all together.

Purpose Of Review: Haemodynamic monitoring is a cornerstone in the diagnosis and evaluation of treatment in critically ill patients in circulatory distress. The interest in using minimally invasive cardiac output monitors is growing. The purpose of this review is to discuss the currently available devices to provide an overview of their validation studies in order to answer the question whether these devices are ready for implementation in clinical practice.

The effect of fluid resuscitation on the effective circulating volume in patients undergoing liver surgery: a post-hoc analysis of a randomized controlled trial.

To assess the significance of an analogue of the mean systemic filling pressure (Pmsa) and its derived variables, in providing a physiology based discrimination between responders and non-responders to fluid resuscitation during liver surgery. A post-hoc analysis of data from 30 patients undergoing major hepatic surgery was performed. Patients received 15 ml kg fluid in 30 min.

Noninvasive pulse pressure variation and stroke volume variation to predict fluid responsiveness at multiple thresholds: a prospective observational study.

Background: Pulse pressure variation (PPV) and stroke volume variation (SVV) are dynamic preload variables that can be measured noninvasively to assess fluid responsiveness (FR) in anesthetized patients with mechanical ventilation. Few studies have examined the effectiveness of predicting FR according to the definition of FR, and assessment of inconclusive values of PPV and SVV around the cut-off value (the "grey zone") might improve individual FR prediction. We explored the ability of noninvasive volume clamp derived measurements of PPV and SVV to predict FR using the grey zone approach, and we assessed the influence of multiple thresholds on the predictive ability of the numerical definition of FR.