Alexander Avian

Systolic Right Ventricular Function in Preterm and Term Neonates: Reference Values of the Tricuspid Annular Plane Systolic Excursion (TAPSE) in 258 Patients and Calculation of Z-Score Values

Background: The tricuspid annular plane systolic excursion (TAPSE) is an echocardiographic measurement to assess right ventricular systolic function in adults and children. Objective: We determined growth- and birth weight-related changes of TAPSE to establish reference values in preterm and term neonates. Methods: A prospective study was conducted in a group of 258 preterm and term neonates (age: 25+0 to 40+6 weeks of gestation, birth weight: 530–4,200 g). Results: The TAPSE ranged from a mean of 0.44 cm (Z-score ±2: 0.30–0.59 cm) in preterm neonates in the 26th week of gestation to 1.03 cm (Z-score ±2: 0.85–1.21 cm) in term neonates in the 41st week of gestation. The TAPSE values increased in a linear way from the 26th to 41st week of gestation. TAPSE, week of gestation and weight are strongly correlated: Pearson’s correlation coefficient was 0.93 for week of gestation – TAPSE (p < 0.001), 0.93 for week of gestation – birth weight (p < 0.001), and 0.89 for birth weight – TAPSE (p < 0.001). There was no statistically significant difference of normal TAPSE values between female and male patients (p = 0.987). Conclusion: Z-scores of TAPSE values were calculated and percentile charts were established to serve as reference data for ready application in preterm and term neonates with structurally normal hearts and with congenital heart disease in the future.

Reading Pulmonary Vascular Pressure Tracings. How to Handle the Problems of Zero Leveling and Respiratory Swings

The accuracy of pulmonary vascular pressure measurements is of great diagnostic and prognostic relevance. However, there is variability of zero leveling procedures, and the current recommendation of end-expiratory reading may not always be adequate. A review of physiological and anatomical data, supported by recent imaging, leads to the practical recommendation of zero leveling at the cross-section of three transthoracic planes, which are, respectively midchest frontal, transverse through the fourth intercostal space, and midsagittal. As for the inevitable respiratory pressure swings, end-expiratory reading at functional residual capacity allows for minimal influence of elastic lung recoil on pulmonary pressure reading. However, hyperventilation is associated with changes in end-expiratory lung volume and increased intrathoracic pressure, eventually exacerbated by expiratory muscle contraction and dynamic hyperinflation, all increasing pulmonary vascular pressures. This problem is amplified in patients with obstructed airways. With the exception of dynamic hyperinflation states, it is reasonable to assume that negative inspiratory and positive expiratory intrathoracic pressures cancel each other out, so averaging pulmonary vascular pressures over several respiratory cycles is most often preferable. This recommendation may be generalized for the purpose of consistency and makes sense, as pulmonary blood flow measurements are not corrected for phasic inspiratory and expiratory changes in clinical practice.

Reference Ranges for Regional Cerebral Tissue Oxygen Saturation and Fractional Oxygen Extraction in Neonates during Immediate Transition after Birth

OBJECTIVE To define reference ranges for regional cerebral tissue oxygen saturation (crSO2) and regional cerebral fractional tissue oxygen extraction (cFTOE) during the first 15 minutes after birth in neonates requiring no medical support. STUDY DESIGN The crSO2 was measured using near infrared spectroscopy (Invos 5100 cerebral/somatic oximeter monitor; Somanetics Corp, Troy, Michigan) during the first 15 minutes after birth for term and preterm neonates. The near infrared spectroscopy sensor was placed on the left forehead. Peripheral oxygen saturation and heart rate were continuously measured by pulse oximetry, and cFTOE was calculated. Neonates were excluded if they required any medical support. RESULTS A total of 381 neonates were included: 82 term neonates after vaginal delivery, 272 term neonates after cesarean delivery, and 27 preterm neonates after cesarean delivery. In all neonates, median (10th-90th percentiles) crSO2 was 41% (23-64) at 2 minutes, 68% (45-85) at 5 minutes, 79% (65-90) at 10 minutes, and 77% (63-89) at 15 minutes of age. In all neonates, median (10th-90th percentiles) cFTOE was 33% (11-70) at 2 minutes, 21% (6-45) at 5 minutes, 15% (5-31) at 10 minutes, and 18% (7-34) at 15 minutes of age. CONCLUSION We report reference ranges of crSO2 and cFTOE in neonates requiring no medical support during transition immediately after birth. The use of cerebral oxygenation monitoring and use of these reference ranges in neonates during transition may help to guide oxygen delivery and avoid cerebral hypo-oxygenation and hyperoxygenation.

Reference values of tricuspid annular peak systolic velocity in healthy pediatric patients, calculation of z score, and comparison to tricuspid annular plane systolic excursion.

The tricuspid annular peak systolic velocity (TAPSV) is an echocardiographic measurement assessing right ventricular systolic function in children and adults. We determined the growth-related changes of the TAPSV to establish the references values for the entire pediatric age group. A prospective study was conducted of a group of 860 healthy pediatric patients (age 1 day to 18 years; body surface area [BSA] 0.14 to 2.30 m(2)). We determined the effects of age, gender, and BSA on the TAPSV values. Stepwise linear multiple regression analysis was used to estimate the TAPSV from the age, BSA, and gender. A correlation of normal TAPSV with normal tricuspid annular plane systolic excursion values was performed. The TAPSV ranged from a mean of 7.2 cm/s (z score ± 2: 4.8 to 9.5 cm/s) in the newborn to 14.3 cm/s (z score ± 2: 10.6 to 18.6 cm/s) in the 18-year-old adolescent. The TAPSV values showed a positive correlation with age and BSA, with a nonlinear course. No significant difference was found in the TAPSV values according to gender. A significant correlation was found between the TAPSV and tricuspid annular plane systolic excursion values in our pediatric population. In conclusion, the z scores of the TAPSV values were calculated, and percentile charts were established to serve as reference data for patients with congenital heart disease.

The elevated preoperative platelet to lymphocyte ratio predicts decreased time to recurrence in colon cancer patients

BACKGROUND Recent evidence indicates that tumor progression involves factors of systemic inflammation, such as platelets and lymphocytes. In this study, we investigated the prognostic relevance of the preoperative platelet to lymphocyte (P/L) ratio on time to recurrence (TTR) and overall survival (OS) in patients with stage II and III colon cancer (CC) who underwent curative resection. METHODS In this retrospective study, 372 CC patients were included. Kaplan-Meier curves and multivariate Cox proportional models were calculated for TTR and OS. RESULTS In univariate analysis, the elevated P/L ratio was significantly associated with decreased TTR (HR = 1.60, 95% CI = 1.02 to 2.51, P = .040) and remained significant in multivariate analysis (HR = 1.65, 95% CI = 1.05 to 2.58, P = .030), where HR and CI represent Hazard ratio and confidence interval, respectively. Patients with elevated P/L ratio showed a median TTR of 116 months. In contrast, patients with low P/L ratio had a median TTR of 132 months. In OS analysis, the elevated P/L ratio showed a trend toward decreased OS in univariate analysis (HR = 1.54, 95% CI = .95 to 2.48, P = .079). CONCLUSION In this study, we identified the preoperative P/L ratio as a prognostic marker for TTR in stage II and III CC patients.

Zero reference level for right heart catheterisation

Although in the pulmonary circulation small pressure differences may alter the categorisation of patients, there is no consensus on a standard zero reference level (ZRL). In the supine position, ZRL is mostly set at “5 cm below anterior thorax surface”, “1/3 thoracic diameter below anterior thorax surface”, “mid-thoracic level” or “10 cm above table level”. We retrospectively assessed the distance of these four ZRLs from computed tomography-derived right and left atrial centre levels and from one another in patients undergoing right heart catheterisation and calculated the respective differences in pressure readings. We included 196 consecutive patients. The ZRL at “1/3 thoracic diameter” was most often (98.5%) level with the right atrium, and the ZRL at “mid-thoracic level” was level with the left atrium (97.4%), revealing a median (range) pressure difference of -0.3 (-3.0–1.3) and 0.2 (-2.0–1.3) mmHg from the right and left atrial centre level, respectively. The largest differences (8.0 (2.0–15.4) mmHg) were found between the ZRLs “5 cm below anterior thorax surface” and “10 cm above table level”. Accordingly, 59% versus 80% of patients would be classified with pulmonary hypertension and 7% versus 38% with elevated left heart pressures. The choice of ZRL strongly influences pulmonary pressure readings and pulmonary hypertension classification. 1/3 thoracic diameter mostly represents the right atrium while the left atrium is best represented by the mid-thoracic level. Choice of pulmonary circulation zero reference level influences classification of pulmonary hypertension http://ow.ly/oZ9lQ

Regional Oxygen Saturation of the Brain and Peripheral Tissue during Birth Transition of Term Infants

OBJECTIVE To evaluate regional tissue oxygenation of the brain and preductal and postductal peripheral (muscle) tissue during immediate transition after birth, and to correlate with peripheral preductal and postductal arterial oxygen saturation. STUDY DESIGN We conducted a prospective observational study. With near-infrared spectroscopy (NIRS), changes in regional oxygen saturation of the brain (rSO2brain), peripheral preductal tissue (rSO2pre), and peripheral postductal tissue (rSO2post) were measured during the first 10 minutes of life in 59 healthy term infants after elective caesarean delivery. Fractional tissue oxygen extraction was calculated for all 3 regions. RESULTS Mean rSO2brain increased rapidly from 44% (3 minutes) to 76% (7 minutes); thereafter no significant change occurred. Mean rSO2pre and rSO2post increased constantly from minute 3 to minute 10, from 36%(pre)/27%(post) to 66%(pre)/58%(post). Fractional tissue oxygen extraction decreased in all 3 regions during the first minutes of life. Fractional tissue oxygen extraction of the brain did not change significantly after 5 minutes, and preductal and postductal fractional tissue oxygen extraction did not change significantly after 8 minutes. CONCLUSIONS During transition, the brain had the highest saturation levels, indicating a preference of oxygen delivery to the brain. Fractional tissue oxygen extraction of the brain reached a plateau earlier compared with peripheral tissue.

Systolic Right Ventricular Function in Children and Young Adults with Pulmonary Artery Hypertension Secondary to Congenital Heart Disease and Tetralogy of Fallot: Tricuspid Annular Plane Systolic Excursion (TAPSE) and Magnetic Resonance Imaging Data

OBJECTIVE   The tricuspid annular plane systolic excursion (TAPSE), as echocardiographic index to assess right ventricular (RV) systolic function, has not been investigated thoroughly in children and young adults with tetralogy of Fallot (TOF) and pulmonary artery hypertension secondary to congenital heart disease (PAH-CHD). PATIENTS   TAPSE values of 49 patients with PAH-CHD and 156 patients with TOF were compared with age-matched normal subjects. TAPSE values were also compared with RV ejection fraction (RVEF) and RV indexed end-diastolic volume (RVEDVi) determined by magnetic resonance imaging in PAH-CHD and TOF patients. RESULTS   Patients with a PAH-CHD showed a positive correlation between TAPSE with RVEF (r= 0.81; P < 0.001) and a negative correlation between TAPSE with RVEDVi (r=-0.67; P < 0.001). Similarly, in our TOF patients, a positive correlation between TAPSE with RVEF (r= 0.65; P < 0.001) and a negative correlation between TAPSE with RVEDVi (r=-0.42; P < 0.001) was seen. CONCLUSIONS   Significant pressure overload in PAH-CHD patients and volume overload in TOF patients lead to a decreased systolic RV function, determined by TAPSE and magnetic resonance imaging and to increased RVEDVi values, determined by MRI, with time.

Characterization of Patients With Borderline Pulmonary Arterial Pressure

BACKGROUND Resting mean pulmonary artery pressure (mPAP) values between 20 and 25 mm Hg are above normal but do not fulfill the criteria for pulmonary hypertension (PH). The clinical relevance of such borderline hemodynamics is a matter of discussion. METHODS We focused on patients who underwent right-sided heart catheterization during rest and exercise for symptoms indicative of PH or due to underlying disease associated with an increased risk for pulmonary arterial hypertension and characterized the patients according to their resting mPAP. Patients with manifest PH (mPAP ≥ 25 mm Hg) were excluded. RESULTS We included 141 patients, 32 of whom presented with borderline hemodynamics (20 < mPAP < 25 mm Hg). Borderline patients were older (65.8 ± 12.5 years vs 57.3 ± 12.5 years, P = .001) and more often had cardiac comorbidities (53% vs 15%, P < .001) or decreased lung function (47% vs 16%, P < .001) as compared with patients with resting mPAP < 21 mm Hg. After correction for age, borderline patients had significantly increased pulmonary vascular resistance (2.7 ± 0.7 Wood units vs 1.8 ± 0.8 Wood units, P < .001) and mPAP/cardiac output (CO) and transpulmonary gradient/CO slopes (both P < .001) as well as lower peak oxygen uptake (16.9 ± 4.6 mL/min/kg vs 20.9 ± 4.7 mL/min/kg, P = .009) and 6-min walk distance (383 ± 120 m vs 448 ± 92 m, P = .001). During follow-up (4.4 ± 1.4 years), the mortality rate of borderline patients vs patients with resting mPAP < 21 mm Hg was 19% vs 4%. CONCLUSIONS In patients undergoing right-sided heart catheterization with exclusion of manifest PH, borderline elevation of pulmonary arterial pressure is associated with cardiac and pulmonary comorbidities, decreased exercise capacity, and a poor prognosis.

Perioperative morbidity and complications in minimal access surgery techniques in obese patients with degenerative lumbar disease

The medical profession is increasingly confronted with the epidemic phenomenon of obesity. Its impact on spine surgery is not quite clear. Published data concerning the use of minimally invasive surgery (MIS) in the spine among obese patients is scarce. The purpose of the present retrospective study was to evaluate perioperative as well as postoperative complication rates in MIS fusion of the lumbar spine in obese, overweight and normal patients classified according to their body mass index. Lumbar MIS fusion was performed by means of TLIF procedures and/or posterolateral fusion alone. A laminotomy was performed in patients with spinal stenosis. Of 72 patients, 39 underwent additional laminotomy for spinal stenosis. No differences were registered in respect of the numbers of fused segments or cages. Any harmful event occurring peri- or postoperatively was noted and included in the statistical analysis. No infection at the site of surgery or severe wound healing disorder was encountered. We registered no difference in blood loss, drainage, or the length of the hospital stay between the three BMI groups. We also observed no difference in complication rates between the three groups. This study confirms the low soft tissue damage of minimal access surgery techniques, which is an important type of surgery in obese patients. The smaller approach helps to minimize infections and wound healing disorders. Moreover, deeper regions of wounds are clearly visualized with the aid of tubular retractors.