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The history of invasive blood pressure measurement, documented in the literature, begins with animal experiments in the 18th century. Stephen Hales was the first who published the methodology and results of invasive blood pressure measurements in „Statical Essays containing Haemastatics" in 1733, however, the measurements, including determination of the venous pressure, aortic blood flow rate, cardiac output, and others parameters in different situations were made in the first and second decades of the 18th century. Poisseuille improved the measurement of the blood pressure with the invention of the hemodynamometer, U-tube filled with mercury. Continuous registration of blood pressure has been made possible since 1847 by the kymograph - Ludwig's invention and the use of a float in the hemodynamometer. For the first time in humans was this method used by Faivre (1856) in three men during limb amputation. To measure blood pressure in various parts of the circulation, including the heart was necessary to introduce catheterizations. Catheterizations in experimental animals were used by Claude Bernard, Chauveau and Marey. The greatest contribution to the development of methods for cardiac catheterization in humans have Dieffenbach, Bleichröder, Unger, Montanari and Nobel Prize winner Forssmann. Very important role in the further development of cardiovascular catheterization played later Klein, Cournand, Richardson, Swan and Ganz. The exact year of beginning of the invasive blood pressure measurement in neonates is unknown. In 1938, Woodbury published a paper about measuring blood pressure in a. umbilicalis using Hamilton's hypodermic manometer. Diamond (1947) and James (1959) contributed to the development of catheterization of umbilical vessels. At the beginning of the sixties of the 20th century, thanks to the construction of accurate electromanometers and suitable catheters, there was a breakthrough in the invasive measurement of blood pressure in newborns. Wallgren, Rudolph, Moss, Gupta and Scopes were the pioneers of invasive blood pressure measurement in newborns. Recently, the direct invasive monitoring of blood pressure in neonatology is the gold standard. This method is necessary when obtaining beat-to-beat BP values and when non-invasive methods cannot be used. [ABSTRACT FROM AUTHOR]

Relationships between the values of heart rate variability and blood pressure and parameters of growth and development in premature infants Introduction: The dynamics of the development of the cardiovascular system in the early postnatal period also depends on the maturity of the newborn. The aim of the study was to determine the relationships between cardiovascular parameters – heart rate variability, its components (LF, HF), pulse intervals (interbeat intervals – IBI), heart rate, systemic blood pressure and parameters reflecting development and growth – gestational age, postconceptional age, birth and actual weight in the group of premature babies in the first weeks of life. Methods: In 43 premature infants of various gestational ages, birth and actual weights, at a mean postconception age of 34.6 weeks, blood pressure and heart rate were continuously and non-invasively recorded. Blood pressure was recorded continuously for 2–5 minutes under standard conditions using a Portapres device (FMS). For each child, a stationary segment of the record containing 250 beat-to-beat blood pressure values was analyzed. The variability of interbeat intervals was determined by spectral analysis (total power, powers in high-frequency and low-frequency bands) in 35 children. Results: Correlation tests (Pearson´s and Spearman´s) revealed positive correlations between gestational, postconceptional age, birth and actual weight and mean value of pulse intervals (IBI), spectral total power of the IBI variability, as well as spectral powers in HF and LF bands, and diastolic and mean blood pressure. There was a significant negative correlation between the ages and weights and mean heart and respiratory rate. Conclusion: Preterm infants with higher gestational and postconceptional age, birth and actual weight have higher total power of heart rate variability.This is not only a consequence of the increase in spectral power in the HF band, but also in the LF band, which through the activities of the sympathetic and parasympathetic systems reflects mainly baroreflex activity. Together, the mean heart rate is lower and blood pressure, diastolic and mean are higher. The identified relationships point to the increasing baroreflex sensitivity and to the maturation of regulatory circuits of the cardiovascular system in premature infants. [ABSTRACT FROM AUTHOR]

hototherapy is the most frequent therapeutic intervention in neonatal wards during the first days of life. The beneficial effect of light on decreasing serum bilirubin level was first described by Cremer and colleagues in the 1950s. Since then, phototherapy has been used effectively in the treatment of severe hyperbilirubinaemia and has almost completely eliminated exchange transfusion. Phototherapy is a non-invasive method, but, in addition to decreasing bilirubin levels, it may affect some other function, e.g. organ perfusion, especially in skin, peripheral vascular resistance, blood flow distribution, heart frequency, systemic blood pressure and breathing. The next component of applied light is a certain influx of heat that warms the body surface up. There is a risk of exogenous overheating and increased water loss by skin. We analyzed the effect of phototherapy on blood pressure and other parameters such as heart rate, respiratory rate, oxygen saturation, skin and rectal temperature. Comparison of control group (n=20) with patients with hyperbilirubinaemia and phototherapy (n=20) showed significant changes in some monitored parameters. Systolic, mean and diastolic blood pressure decreased significantly after the first hour of phototherapy (p=0.001; p=0.000; p=0.001), while at the end of the 2nd hour of phototherapy the drop was even more pronounced (p=0.002; p=0.000; p=0.003). During phototherapy, heart rate increased after 1 hour, even more significantly at the end of the 2nd hour of phototherapy (p=0.008; p=0.002), the respiratory rate also increased (p=0.033; p=0.015). These changes were accompanied by increasing skin and central (rectal) temperature. Based on the results, there are changes in some physiological parameters during phototherapy in newborns. Consistent monitoring of vital signs should therefore be an obvious part of care of the newborn during the treatment with blue light. [ABSTRACT FROM AUTHOR]

Postnatal transition is a complex process predominantly affecting cardiovascular and respiratory system immediately after birth. This includes spontaneous and regular breathing and physiological, as well as anatomical cardiovascular changes. Technological progress offers new possibilities for monitoring of vital signs more effectively and non-invasively. Heart rate is the most useful parameter reflecting the course of immediate postnatal adaptation and together with blood oxygen saturations belong to standard monitoring of adaptation process. New technologies, such as heart rate variability and near-infrared spectroscopy have been recently implemented into neonatal clinical research and practice. Better understanding of physiology and pathophysiology of postnatal adaptation mechanisms can help the practitioners to adjust preventative and therapeutic interventions and minimize their adverse effects, especially in preterm babies. Recent data about cardiovascular and haemodynamic monitoring during the early postnatal and neonatal period is presented in this article. [ABSTRACT FROM AUTHOR]

Apnea, especially in preterm newborns (AoP) is one of the common problems encountered at neonatal units. Numerous factors are likely to play a role in the etiology of apnea. Recent data sugest a role for genetic predisposition of AoP. It seems, that physiological rather than pathological immaturity of the respiratory, or cardiorespiratory control, play a major part in the pathophysiology of AoP. Immaturity of the brainstem, cerebral cortex, receptors of the lungs and the airways as well as of the chemoreceptors contribute to the development of apnea in preterm newborns. Several neurotransmitters (GABA, adenosin, endorphins) and their maturational changes are including in pathogenesis of apnea, too. The instability of the upper airway in preterm infants, asynchrony of musculature of the upper airway and diaphragm, pathological changes in the upper airway and malformations of the central nervous system might also contribute to the occurrence and severity of AoP. In newborns, apnea occurs more frequently in active sleep than in quiet sleep and the frequency of apnea in active sleep is higher in the warm conditions. Durations of apnea correlate with the body heat loss. Cardiovascular changes during apnea - bradycardia, peripheral vasoconstriction and various changes in peripheral blood flow and pressure occur together with changes in ECG. The standard clinical management of apnea includes non-pharmacological treatment (eliciting arousal reactions and reflex breathing by mechanical skin, or mucosa stimulations), pharmacological treatment (methylxanthines are preferred) and application of continuous positive airway pressure (CPAP) or in severe apnea - mechanical ventilation. [ABSTRACT FROM AUTHOR]

This paper presents an overview of cardiac chronotropic regulation determinants in newborns, which are reflected in mean heart rate (HR) and heart rate variability (HRV). Heart rate and heart rate variability in newborns are determined by many factors. Heritability and maturation play major role. Factor of the maturation can be seen in HR and HRV differences between healthy full term and preterm newborns as well as in changes over early postnatal time. These parameters in newborns are influenced also by many other factors as gender, nutrition, sleep, breathing pattern/ventilation, etc. Autoregulation and extrinsic regulation of cardiac activity has its own specificities in newborns. Homeometric mechanism (depended on HR) is dominant and baroreflex sensitivity is reduced, mainly in premature newborns. Complex cardiac regulation can be studied and evaluated by cardiac reflexes. Examination of the reflexes in newborns is limited. Therefore, new approaches for the study of maturation cardiac control are developed taking into consideration all cardiac activity in newborns determinants. [ABSTRACT FROM AUTHOR]

Cystic dysplasia of the rete testis (CDRT) is a very rare cause of a paediatric scrotal mass often associated with renal and other genitourinary tract anomalies. These complex malformations are probably due to a developmental defect of the mesometanephric system during embryogenesis. A case of asymptomatic scrotal swelling in a 4-year-old boy is presented. Ultrasonography, showed a cystic lesion of the left testis associated with absence of the left kidney. Orchiectomy was performed because of extensive gonad involvement. Pathologic examination revealed multiple, anastomosing, irregular cystic spaces of varying sizes and shapes predominantly located in the region of the rete testis. The cysts had spread irregularly, displacing the testicular parenchyma, which was subsequently compressed under the tunica albuginea. Preoperative diagnosis of CDRT is easy if age, precise localisation, characteristic ultrasonographic features and other genitourinary malformations are considered. Other paediatric cystic lesions should be included in the differential diagnosis. It is possible to cure CDRT by orchiectomy or by conservative treatment. Nowadays the later option is preferred, but diagnosis of CDRT must be precisely established and followed by careful monitoring. [ABSTRACT FROM AUTHOR]

As only one experimental study examining the effects of haemodilution on circulatory responses to hyperthermia has so far been published and there is no information on respiratory responses to hyperthermia during haemodilution or anaemia, this paper studied the effects of acute normovolemic haemodilution on cardiorespiratory changes during 42°C hyperthermia and its recovery by body surface cooling in 16 anaesthetized adult rabbits. The animals were divided into two groups: haemodiluted group (Hct = 18.6 ± 0.4%) and control group (Hct = 41.1 ± 0.9%). In the haemodiluted group, acute normovolemic haemodilution was induced by 60% replacement of total blood volume with dextran. Haemodilution produced significant increases in minute volume ( V E , p< 0.02), heart rate (HR, p< 0.02) and central venous pressure (CVP, p< 0.02), but there was no significant change in mean arterial pressure (MAP). Hyperthermia caused significant increases in V E and HR in both the groups; however, V E and HR values were significantly higher in the haemodiluted group compared to the controls. CVP decreased ( p< 0.05) during 42°C hyperthermia only in the controls in the panting phase. MAP did not significantly change during over-heating in controls, but it significantly ( p< 0.02) rose in the haemodiluted group. In the recovery phase, cooling led to significant decreases in HR and MAP in both the groups and to further increases in V E ( p< 0.05) in controls, whereas V E decreased in the haemodiluted animals. There were found no significant cardiorespiratory differences between the two groups during cooling. Hyperthermia was accompanied by the higher values of minute volume and heart rate in the haemodiluted animals, indicating a greater activation of the respiratory and cardiovascular systems, which could result in diminished functional cardiorespiratory reserve and a higher risk of respiratory and circulatory failures in haemodiluted/anaemic animals during hyperthermia. In the phase of recovery of the body temperature there were no significant cardiorespiratory differences found between the two groups. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate short-term changes in cardiovascular autonomic dysregulation in young patients with Type 1 diabetes mellitus (DM). Repeated analysis of spontaneous heart rate oscillations (heart rate variability - HRV) was conducted at baseline and after a follow-up period of 17 month. R-R intervals were recorded over 1h in the supine position and heart rate signal was quantified using standard time and frequency domain and short-term complexity measures. During the follow-up measurement the low frequency oscillations of heart rate were significantly elevated (p = 0.03) and sample entropy values reduced (p = 0.03) compared with the baseline measurement. HRV measures were significantly negatively correlated with the duration of DM. In conclusion, the data indicate that cardiovascular autonomic neuropathy progresses in relatively short time frames and depends on the duration of DM. Its progression is associated with glycemic control. Complexity and variability analyses of heart rate provide a sensitive tool for the detection and follow-up of cardiovascular autonomic dysregulation in patients with Type 1 diabetes mellitus. [ABSTRACT FROM AUTHOR]

In severe respiratory insufficiency, neonatal and pediatric patients should be ventilated artificially by a ventilator. Aim of this experimental study was to evaluate whether the newly developed ventilator Chirana Aura V may effectively ventilate the lungs of animals with two different models of acute lung injury: acute respiratory distress syndrome (ARDS) induced by repetitive saline lavage and meconium aspiration syndrome (MAS) induced by intratracheal instillation of neonatal meconium. The experiments were performed on 10 adult rabbits (New Zealand white). In ARDS group (n=5), the lungs were repetitively lavaged with saline (30 ml/kg) until partial pressure of oxygen (PaO2) in arterial blood was under 26.7 kPa at inspiratory fraction of oxygen FiO2=1.0. In MAS group (n=5), animals were instilled 4 ml/kg of suspension of human meconium (25 mg/ml). When the model of acute lung injury was developed, animals were ventilated for additional 2 hours with pressure control ventilation (PCV) regime by ventilator Chirana Aura V. Ventilatory parameters, blood gases, acid-base balance, end-tidal CO2, O2 saturation of hemoglobin, oxygenation indexes, ventilation efficiency index, dynamic lung compliance, and right-to-left pulmonary shunts were measured and calculated in regular time intervals. In both experimental groups, used ventilatory settings provided acceptable gas exchange within the period of observation. Thus, the results indicate that ventilator Chirana Aura V might be suitable for ventilation of animal models of acute lung injury. However, further pre-clinical investigation is needed before its use may be recommended in neonatal and/or pediatric patients with acute lung injury. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study was to test the hypothesis that control of breathing via Hering–Breuer reflex (HB) is influenced by lipopolysaccharide (LPS)-induced fever in rats. Animals were injected intraperitoneally with LPS and control group with an equivalent volume of saline. HB reflex was elicited by inflations of the lungs followed by occlusion of the airways under control of esophageal pressure. Duration of HB reflex (T apnoe) was continuously reduced as body temperature rose during experiment. Compared to normothermic controls, animals with fever had significant shortening of T apnoe at 240min and 300min after LPS administration. Fever was further accompanied by a reduction in the strength of HB reflex (inhibitory ratio, IR). In comparison with controls, significant decrease of IR was observed at 300min after LPS injection. Conclusion: altered neural control of breathing demonstrated by decreased power of Hering–Breuer inflation reflex in conditions of LPS-induced fever may facilitate thermal tachypnoea and/or play a role in the origin of respiratory instability accompanying febrile response. [Copyright &y& Elsevier]

Aim: To determine the efficacy of the expulsion effect of high-frequency jet ventilation (HFJV) on meconium clearance from the airways in comparison with conventional suctioning in adult rabbits with meconium aspiration.Methods: Experiments were carried out on tracheotomized, anaesthetized and paralysed adult rabbits. A suspension of human meconium in saline (25 mg ml(-1), 4 ml kg(-1)) was instilled into the tracheal cannula. When respiratory failure developed, saline lavage (10 ml kg(-1) in 3 portions) was performed during conventional ventilation or by means of the inpulsion and expulsion regime of HFJV. Animals were further ventilated for 2 h with either conventional ventilation or HFJV.Results: There was no significant difference between groups in the amount of meconium recovered by lavage. Compared to conventional ventilation, the application of HFJV enhanced the elimination of carbon dioxide, increased lung compliance and diminished right-to-left shunts after 30 min of ventilatory treatment. Oxygenation also improved during HFJV, although this was not a consistent finding during the ventilation period.Conclusion: HFJV improved gas exchange, lung compliance and reduced right-to-left pulmonary shunts, but saline lung lavage by HFJV was not found to be more efficient than lavage during conventional ventilation in rabbits with meconium aspiration. [ABSTRACT FROM AUTHOR]

Introduction: Impaired cardiac autonomic regulation is likely important contributor to a potential cardiac complications in major depression. The knowledge regarding the depression effect on cardiac regulation in adolescent age is limited. Aim was to study short-term heart rate variability (HRV) as an index of cardiac autonomic control in never-treated major depressive disorder (MDD) adolescent patients using linear and nonlinear methods related to depressive symptoms severity. Methods: We have examined 20 MDD girls and 20 healthy age-matched girls at the age from 15 to 18 years. The ECG was recorded in three positions: supine - orthostasis - supine. The HRV was analyzed using linear (time and frequency analysis) and novel nonlinear (symbolic dynamics, time assymetry) methods. The severity of depressive symptoms was evaluated using the scales Montgomery-Asberg Depression Rating Scale (MADRS) and Children’s Depression Inventory (CDI). Results: Several HRV linear and nonlinear parameters were significantly reduced in MDD group compared to controls in supine rest and during orthostasis. The HRV nonlinear analysis indices significantly correlated with depressive symptoms severity. Conclusions: Linear and nonlinear analyses revealed reduced magnitude and complexity of the HRV indicating impaired neurocardiac regulation in adolescent major depression. In addition, new approach of HRV analysis using nonlinear methods provided important information about depressive symptoms severity and cardiac autonomic regulation relations. [ABSTRACT FROM AUTHOR]