Effects of Volume Guaranteed Ventilation Combined with Two Different Modes in Preterm Infants

BACKGROUND

Volume-controlled ventilation modes have been shown to reduce duration of mechanical ventilation, incidence of chronic lung disease, failure of primary mode of ventilation, hypocarbia, severe intraventricular hemorrhage, pneumothorax, and periventricular leukomalacia in preterm infants when compared with pressure limited ventilation modes. Volume-guarantee (VG) ventilation is the most commonly used mode for volume-controlled ventilation. Assist control, pressure-support ventilation (PSV), and synchronized intermittent mandatory ventilation (SIMV) can be combined with VG; however, there is a lack of knowledge on the superiority of each regarding clinical outcomes. Therefore, we investigated the effects of SIMV+VG and PSV+VG on ventilatory parameters, pulmonary inflammation, morbidity, and mortality in preterm infants.

METHODS

Preterm infants who were born in our hospital between 24-32 weeks gestation and needed mechanical ventilation for respiratory distress syndrome were considered eligible. Patients requiring high-frequency oscillatory ventilation for primary treatment were excluded. Subjects were randomized to either SIMV+VG or PSV+VG. Continuously recorded ventilatory parameters, clinical data, blood gas values, and tracheal aspirate cytokine levels were analyzed.

RESULTS

The study enrolled 42 subjects. Clinical data were similar between groups. PSV+VG delivered closer tidal volumes to set tidal volumes (60% vs 49%, P = .02). Clinical data, including days on ventilation, morbidity, and mortality, were similar between groups. Chronic lung disease occurred less often and heart rate was lower in subjects who were ventilated with PSV+VG. The incidence of hypocarbia and hypercarbia were similar. Interleukin-1β in the tracheal aspirates increased during both modes.

CONCLUSION

PSV+VG provided closer tidal volumes to the set value in ventilated preterm infants with respiratory distress syndrome and was not associated with overventilation or a difference in mortality or morbidity when compared to SIMV+VG. Therefore, PSV+VG is a safe mode of mechanical ventilation to be used for respiratory distress syndrome.

Effects of a closed system suction connector on airway resistance in ventilated neonates

BACKGROUND/AIM

Increased airway resistance reduces the effectiveness of ventilation treatment. Endotracheal tubes (ETTs) and connectors contribute to resistance. However, the effect of a closed system suction (CSS) connector is not well known. We compared the in vivo resistance occurring with a CSS connector with that of the standard connector.

MATERIALS AND METHODS

This prospective study was conducted at Gazi University Hospital's neonatal intensive care unit. Intubated neonates were studied for two cycles; each cycle contained two periods of ETT + connector pairs (15 min/period) as follows: cycle 1 [A: long ETT + standard connector; B: long ETT + CSS connector] and cycle 2 [C: shortened ETT + standard connector; D: shortened ETT + CSS connector]. Resistance of 40 breaths/period was averaged for each case, and the means were analyzed by Wilcoxon test for pairwise comparisons between standard and CSS connectors. As each case provided two cycle data, 16 cycle data were compared.

RESULTS

The CSS connector increased resistance by 13.8% (range: 3.0%-22.1%) compared to the standard connector; P < 0.001. The resistance increase was similar between long [17.3% (range: 3.0%-17.7%)] and shortened ETTs [15.3% (range: 5.0%-29.6%)]; P = 0.834.

CONCLUSION

CSS connectors were found to increase airway resistance in ventilated neonates. The contribution of CSS should be considered during ventilation, particularly in the presence of difficulty in providing sufficient tidal volume.

Impact of mode of delivery on skin microcirculation in term healthy newborns within the first day of life

BACKGROUND

Microcirculation is an important component of hemodynamic physiology. It can be assessed simply by clinical scores or by a variety of techniques including sidestream dark field (SDF) imaging and peripheral perfusion index (PI) measurements. Mode of delivery may have affects on microcirculation during transitional period. The aim of this study was to compare skin microcirculation in newborns born via vaginal delivery (VD) or cesarian section (C/S).

METHODS

Term healthy newborns not requiring NICU admission were included. Vital signs were recorded. Skin microcirculation was determined by clinical scoring including capillary refill time, skin color, warmth of extremities, by SDF imaging where capillary density and microvascular flow is determined and by PI measurements where pulsatile and nonpulsatile capillary flow is measured. Assessments were done at 30 min and 24 h of life. Results were compared between VD and C/S groups and overtime.

RESULTS

There were 12 newborns in VD group and 25 newborns in C/S group. No difference was observed in microcirculation assessments between groups. However VD group had increased hyperdynamic flow overtime.

CONCLUSION

In healthy term newborns microcirculation does not seem to be affected by mode of delivery, however results may differ in sick or preterm newborns.

Functional brain maturation of prematurely born, growth discordant monochorionic twins assessed by aEEG

The amplitude-integrated electroencephalogram (aEEG) is a simple and convenient tool for brain function monitoring. It is being more widely used in monitoring high risk neonates in neonatal intensive care units. Normal values and patterns for aEEG activity in preterm infants are still being developing. Here we report the functional brain maturation of preterm twin siblings with aEEG who were severely affected by fetal growth discordance. The aEEG records of growth retarded twin was compared with her appropriate for gestational age sibling in order to see if there is also a developmental discordance in the functional brain maturation of these twins.

Ileo-ileal intussusception in a premature neonate: an unusual cause of NEC in premature babies

Intussusception is a rare entity in neonates. It may present with non-specific signs including abdominal distension, feeding intolerance, vomiting and bloody stools. Symptomatology is similar to Necrotizing Entero-Colitis (NEC). Ultrasound can help to establish early diagnosis in neonate. A 27-week preterm newborn was initially suspected as NEC based on abdominal distention, bilious vomiting, worsening clinical condition and dilated loops of bowel on X-ray, which turned out to be ileo-ileal intussusception. Diagnosis was made by ultrasound obtained for a palpable mass to rule out intra abdominal abscess and lack of improvement in clinical condition despite 5 days of conservative treatment. Surgery was performed consisting of removal of the necrotic intussusception area and end-to-end anastomosis and patient was discharged from hospital on day 60 of life. As a conclusion, pathological abdominal findings in preterm newborns can also be due to conditions other than NEC and ultrasound may be a useful tool for timely and accurate diagnosis.

The risk assessment study for hemolytic disease of the fetus and newborn in a University Hospital in Turkey

Maternal red-cell alloimmunization occurs when a woman's immune system is sensitized to foreign red-blood cell surface antigens, leading to the production of alloantibodies. The resulting antibodies often cross the placenta during pregnancies in sensitized women and, if the fetus is positive for red-blood-cell surface antigens, this will lead to hemolysis of fetal red-blood cells and anemia. The most severe cases of hemolytic disease in the fetus and newborn baby are caused by anti-D, anti-c, anti-E and anti-K antibodies. There are limited data available on immunization rates in pregnant women from Turkey. The aim of the present study was to provide data on the frequency and nature of maternal RBC alloimmunization in pregnant women in a tertiary care hospital. In this study, we retrospectively evaluated the indirect antiglobulin test results of Rh-negative pregnant women performed in our Blood Bank between 2006 and 2012. Indirect antiglobulin test positive women also underwent confirmatory antibody screening and identification. During the study period, 4840 women admitted to our antenatal clinics. With regards to the major blood group systems (ABO and Rh), the most common phenotype was O positive (38.67%). There were 4097 D-antigen-positive women (84.65%) and 743 women with D-antigen-negative phenotype (15.35%). The prevalence of alloimmunization was found to be 8.74% in D-antigen negative group. Despite prophylactic use of Rh immunglobulins, anti-D is still a common antibody identified as the major cause of alloimmunization in our study (anti-D antibody 68.57%, non-D antibody 31.42%). While alloimmunization rate to D antigen was 6.46%, non-D alloimmunization rate was 2.69% among Rh-negative pregnant women. Moreover, detailed identification facilities for antibodies other than anti-D are not available in most of centers across Turkey. However, large-scale studies on pregnant women need to be done in order to collect sufficient evidence to formulate guidelines and to define indications for alloantibody screening and identification.

Use of amplitude-integrated electroencephalography (aEEG) and near infrared spectroscopy findings in neonates with asphyxia during selective head cooling

BACKGROUND

Amplitude-integrated electroencephalogram (aEEG) at <6 h is the best single outcome predictor in term infants with perinatal asphyxia at normothermia. Hypothermia treatment has changed the cutoff values for outcome prediction by using time at onset of normal trace and SWC. Cerebral hemodynamics and oxygenation changes detected by near infrared spectroscopy (NIRS) during hypothermia treatment in aphyxiated neonates are not a well known issue.

AIM

The aim of this study was to investigate the correlations between brain monitoring (amplitude integrated EEG and NIRS) and outcome in asphyxiated full-term infants with moderate/severe hypoxic-ischemic encephalopathy before, during and after hypothermia treatment.

METHOD

Ten neonates were recruited for hypothermia treatment by using the cool cap entry criteria. aEEG and NIRS were applied in 10 and 8 patients, respectively with moderate and severe hypoxic-ischemic encephalopathy before, just after brain cooling and rewarming periods. Patterns and voltages of aEEG backgrounds sleep-wake cycles (SWC) and NIRS values (TOI% and FTOE) were recorded. During the follow up their outcomes were assessed by using the Bayley Scales of Infant Development II.

CONCLUSION

Hypothermia changes the predictive value of early aEEG. Normalization of a baby's aEEG and the appearance of SWCs while being cooled occurs later. In our study one patient had normal aEEG background pattern at 80 and imminent SWC at 90 h after birth and still had normal Bayley scores at 24 months. Time to normal aEEG and SWC appearance should be carefully evaluated during the cooling period. NIRS values were different due to the clinical presentations of the patients.

Long-term monitoring of a critically ill preterm infant with two-channel amplitude integrated electroencephalography

Amplitude integrated electroencephalography (aEEG) is a user friendly technique suitable for long term continuous monitoring of cerebral electrical background activity. It is increasingly being used in monitoring high risk neonates in intensive care units. Newer two-channel aEEG monitors by providing data from both side of the brain may increase the sensitivity for detection of unilateral cerebral injury. Here we report a critically ill preterm neonate with intracranial hemorrhage who was monitored with the two-channel aEEG for 3 weeks continuously. Seizures were clearly detected by monitoring electroencephalographic activity of both hemispheres and efficacy of anticonvulsant therapy was evaluated objectively. Amplitude integrated EEG helps management of critically ill patients as it allows continuous long-term monitoring of brain functions.

Myocardial performance index by tissue Doppler in bronchopulmonary dysplasia survivors

Bronchopulmonary dysplasia (BPD) survivors from the surfactant era were evaluated by echocardiography in a few studies and no significant differences were found between BPD and non-BPD children. In this study, we evaluated these children with myocardial performance index (MPI), which was obtained by tissue Doppler echocardiography (TDE) in addition to the conventional methods. Fifteen children with BPD who did not have any cardiopulmonary symptoms at the time of the study were examined. All children were studied with M-mode, two-dimensional and DE. Pulmonary artery systolic pressures (PAPs) were estimated from tricuspid regurgitant velocity, and MPI for both ventricles were obtained by TDE. Results were compared with those of term-born, age- and sex-matched control children. While the variables obtained by M-mode and DE did not differ between the groups, the right and left ventricular MPI were found to be significantly higher in the BPD group compared with the control group (mean right ventricular MPI 0.48 +/- 0.04 vs. 0.41 +/- 0.05; mean left ventricular MPI 0.47 +/- 0.05 vs. 0.39 +/- 0.06). In addition, mean PAPs values of the patients were found to be significantly higher than those of the controls (30.4 +/- 6.9 mmHg vs. 23.3 +/- 5.3 mmHg), and there was a positive correlation between PAPs and right ventricular MPI values in the BPD group (r = 0.5). While routine echocardiographic examinations revealed no difference between the groups, MPI measurements by TDE technique yielded significantly higher values in the BPD group. To this extent, our study is the first to show that survivors of BPD may, in fact, have a subclinical ventricular dysfunction.

Cardiac functions by myocardial performance index and QT dispersion in survivors of childhood lymphoblastic leukaemia

AIM

Childhood leukaemia treatment contains multiple chemotherapeutic agents in high doses that can cause severe toxic effects on heart and other vital organs. In this respect patients taking cancer chemotherapy are followed for these adverse effects. Echocardiographic myocardial performance index (MPI) was reported as a new method of combined systolic and diastolic function for both adults and children, calculated as isovolumic relaxation time plus isovolumic contraction time divided by ejection time. In addition, it has been postulated that increased inter-lead differences in QT interval (QT dispersion) may be associated with an increased risk of cardiac death. The aim of this study was to determine the probable immediate and late adverse effects of childhood leukaemia treatment containing moderate dose of anthracyclines on heart by MPI and corrected QT dispersion (QTcD).

METHODS

MPI and QTcD in 55 children with leukaemia and 38 healthy controls matched for age and sex were evaluated.

RESULTS

There was no statistically significant difference between MPI values of patients and controls (20.7+/-13.1 (1-59.4) and 16.1+/-13.5 (0.3-77.5), P: 0.1, respectively). Also, there was no significant difference in MPI and QTc values between patients taking active treatment and those who completed the therapy and between the patients given a cumulative dose of anthracycline lower and higher than 250 mg/m2. But QTcD values were found to be higher in patients than controls (0.08+/-0.03 and 0.03+/-0.01, P<0.01, respectively).

CONCLUSIONS

There was no overt cardiotoxicity in our children with leukaemia treated with protocols of ALL BFM 95 and TRALL 2000 (Modified BFM in Turkey) containing moderate dose of anthracyclines. However, they can cause subclinical cardiotoxicity and further monitoring and evaluation with such sensitive and noninvasive methods over a longer period of time are needed.

Sinopulmonary aspergillosis in children with hematological malignancy

Invasive pulmonary aspergillosis is a serious infectious complication in immunocompromised especially neutropenic patients. Despite improvements in early diagnosis and effective treatment, invasive pulmonary aspergillosis is still a devastating opportunistic infection. These infections also interfere with the anticancer treatment. We report our experience in the diagnosis and therapeutic management of sinopulmonary aspergillosis in 4 children with hematologic malignancy. All patients except the first were neutropenic when sinopulmonary aspergillosis was diagnosed. Clinical signs included fever, cough, respiratory distress, swallowing difficulty, headache, facial pain-edema and hard palate necrosis. Radiodiagnostic methods showed bilateral multiple nodular infiltrations, soft tissue densities filling all the paranasal sinuses, and bronchiectasis. Diagnosis of aspergillosis was established by bronchoalveolar lavage in one case, tissue biopsy, positive sputum and positive cytology, respectively, in the other 3 cases. One patient was treated with liposomal amphotericin B and other 3 cases were treated with liposomal amphotericin B + itraconozole. Outcome was favorable in all cases except the one who died due to respiratory failure. Early diagnosis, appropriate treatment and primary disease status are important factors on prognosis of Aspergillus infections in children with hematological malignancy.

Streptococcus oralis as a risk factor for middle cerebral artery thrombosis

We reported a case of an 8-year-old boy who was presented to the emergency department with left-sided hemiparesis. Computed tomography showed hypodense areas in the territory of the right middle cerebral artery, indicating acute cerebral infarct. Diagnostic evaluation was performed to identify the etiology. On the eighteenth day of hospitalization, cerebrospinal fluid cultures yielded Streptococcus oralis. We hypothesized that the source of the oral pathogen was an abscess belonging to his upper left fourth tooth, which, by a transient bacteremia, had invaded the central nervous system, and skipping the meninges caused local inflammatory arteritis of the carotid artery, leading to cerebral infarction. Sulbactam-ampicillin therapy was initiated for 14 days, and he was discharged with anticoagulation therapy.