Role of Crystalloids in the Perioperative Setting: From Basics to Clinical Applications and Enhanced Recovery Protocols.

Perioperative fluid management, a critical aspect of major surgeries, is characterized by pronounced stress responses, altered capillary permeability, and significant fluid shifts. Recognized as a cornerstone of enhanced recovery protocols, effective perioperative fluid management is crucial for optimizing patient recovery and preventing postoperative complications, especially in high-risk patients. The scientific literature has extensively investigated various fluid infusion regimens, but recent publications indicate that not only the volume but also the type of fluid infused significantly influences surgical outcomes. Adequate fluid therapy prescription requires a thorough understanding of the physiological and biochemical principles that govern the body's internal environment and the potential perioperative alterations that may arise. Recently published clinical trials have questioned the safety of synthetic colloids, widely used in the surgical field. A new clinical scenario has arisen in which crystalloids could play a pivotal role in perioperative fluid therapy. This review aims to offer evidence-based clinical principles for prescribing fluid therapy tailored to the patient's physiology during the perioperative period. The approach combines these principles with current recommendations for enhanced recovery programs for surgical patients, grounded in physiological and biochemical principles.

Microcirculatory Differences in Children With Congenital Heart Disease According to Cyanosis and Age.

Background: Congenital heart disease (CHD) is one of the main causes of morbidity and mortality in children. Microcirculatory changes in CHD patients have previously been investigated using a variety of techniques. Handheld videomicroscopy enables non-invasive direct visualization of the microcirculatory bed. The aim of our study was to determine if there are microcirculatory differences among CHD patients based on age and the presence of cyanosis. Methods: A prospective observational study was carried out. Patients with CHD undergoing corrective surgery were evaluated after anesthetic induction prior to surgery. Microcirculation was evaluated using sidestream dark field (SDF) imaging. Hemodynamics and respiratory, biochemical, and tissue perfusion parameters were analyzed. Results: A total of 30 patients were included, of whom 14 were classified as cyanotic and 16 as non-cyanotic. Cyanotic patients had a higher total vessel density (TVD) (p = 0.016), small vessel density (p = 0.004), and perfused small vessel density (p = 0.013), while their microvascular flow index (MFI) was lower (p = 0.013). After adjustment for age and PaO2, cyanotic patients showed increased TVD (p = 0.023), and small vessel density (p = 0.025) compared to non-cyanotic patients but there were no differences on the MFI. Age was directly correlated with total MFI (spearman's rho = 0.499, p = 0.005) and small vessel MFI (spearman's rho = 0.420, p = 0.021). After adjustment for the type of CHD (cyanotic vs. non-cyanotic) patients with MFI and small MFI vessels <3 were younger than those with values ≥3 (p = 0.033 and p = 0.037). Conclusions: SDF-based evaluation of microcirculation in CHD patients showed that patients with cyanotic defects had higher vascular density, as compared to patients with non-cyanotic defects. Younger patients were more likely to have a low MFI regardless of their type of CHD.

Beating-heart aortic arch surgery in neonates and infants.

OBJECTIVES: Aortic arch repair has been shifted from deep hypothermia plus circulatory arrest to cerebral perfusion at tepid temperatures. A step forward is a simultaneous brain-coronary perfusion, allowing beating-heart arch surgery. METHODS: A 'Y' cannula from the arterial line delivers oxygenated blood to brain and heart. The arch is repaired on a beating heart at 25°C. Intracardiac repair is performed after running cardioplegia through the root line. Fifty patients are classified into 3 groups: A, Norwood (8 neonates); B, aortic arch (14 children) and C, aortic arch plus intracardiac repair (28 patients). Associated anomalies in Group C are as follows: ventricular septal defect (10), arterial switch (5), atrial septal defect (4), cor triatriatum (3), aortic commissurotomy (2), comprehensive repair (2), ostium primum (1) and Yasui (1). RESULTS: The mean bypass time was 161 ± 54.44 (range 93-312) min. Mean brain-coronary perfusion was 37.26 ± 10.54 (18-60) min. Mean coronary ischaemia was 31 ± 32.40 (0-160) min. The heart was not arrested in Group B patients. Follow-up was complete for a mean of 30 (1-48) months. Four patients died in the postoperative period. Two required angioplasty for recoarctation. CONCLUSIONS: Selective brain-coronary perfusion is feasible and easy to switch to conventional cardioplegia delivery. Coronary ischaemia can be notably reduced and even 0 min in isolated arch surgery.