Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study

BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348

Computer simulation of the linear and nonlinear optical properties of liquid benzene : its local fields, refractive index and second nonlinear susceptibility

Molecular dynamics (MD) simulation and subsequent analysis of the macroscopic polarization developed in response to a posteriori applied electric fields or of spontaneous fluctuations in the instantaneous polarization under zero applied field is used to assess the nonlinear optical properties of a polarizable liquid. Three strategies are proposed for the electrostatic analysis, all using as input static gas phase (hyper)polarizabilities, obtained from ab initio calculations. All three strategies are shown to accurately reproduce the experimentally measured refractive index and second nonlinear susceptibility of liquid benzene. The simulation also predicts the distribution of orientations and magnitudes of the local electric fields experienced by the molecules in the liquid, and the nonlinear contributions to the local fields. This approach gives an 8% higher estimate of the second nonlinear susceptibility of liquid benzene than the Lorentz local field factor approach, in better agreement with experimental value

The management of HIV in pregnancy: a 10-year experience

Objective: The package of care to reduce HIV mother to child transmission (MTCT) has evolved significantly since trials of ante and intrapartum antiretroviral therapy (ART) in 1994. In the UK MTCT rate has fallen from 25.6% in the 1990s to 0.46%. We review the management of HIV in pregnancy in Brighton in the context of evolving guidelines. Study design: HIV, obstetric and neonatal notes of all HIV positive women, pregnant between 2003 and 2014, were reviewed. Results: 97 pregnancies in 75 women were identified, resulting in 79 live births. Antenatal HIV diagnosis was made in 22 (28%). The proportion of pregnancies in those with known HIV at conception increased over the time period. At conception 58 (60%) were on ART, 33 (57%) of who continued on their original regimen. 34 (35%) initiated ART following conception: 14 known to be HIV positive, 20 diagnosed during pregnancy. Two did not start ART (1 due to miscarriage, 1 as diagnosed post-delivery) and in three cases ART history was unavailable due to transfer to alternative centres. ART was initiated on average at 22 weeks gestation (range 6–34). 4(5%) received Zidovudine (AZT) monotherapy, all before 2006. Choice of combination ART (cART) varied with time reflecting changing guidelines. Prior to 2008 an AZT containing regimen was used in 83% versus 8% after. Planned mode of delivery was documented in 73: 30(41%) planned a normal vaginal delivery (NVD), 43(59%) a caesarean section (CS). The viral load (VL) was <50 copies/mL in 58(76%) at 36 weeks and 64(84%) at delivery. 90% with a detectable VL at 36 weeks delivered via CS. 100% received neonatal post-exposure prophylaxis (PEP): 68(88%) AZT monotherapy, 9(12%) cART. 84% initiated PEP within four hours. 90% completed 28 days. 8(10%) babies experienced side effects. In the 10-year review period, one infant (1.3%) was diagnosed HIV positive. Both mother and infant received care in accordance with guidelines, including neonatal PEP within 4 hours. Conclusion: Care of the HIV positive pregnant woman in Brighton has been successful with overall transmission consistent with that seen nationally. Despite effective preventative strategies MTCT remains a risk and women should be counselled accordingly

The management of HIV in pregnancy: a 10-year experience

Objective: The package of care to reduce HIV mother to child transmission (MTCT) has evolved significantly since trials of ante and intrapartum antiretroviral therapy (ART) in 1994. In the UK MTCT rate has fallen from 25.6% in the 1990s to 0.46%. We review the management of HIV in pregnancy in Brighton in the context of evolving guidelines. Study design: HIV, obstetric and neonatal notes of all HIV positive women, pregnant between 2003 and 2014, were reviewed. Results: 97 pregnancies in 75 women were identified, resulting in 79 live births. Antenatal HIV diagnosis was made in 22 (28%). The proportion of pregnancies in those with known HIV at conception increased over the time period. At conception 58 (60%) were on ART, 33 (57%) of who continued on their original regimen. 34 (35%) initiated ART following conception: 14 known to be HIV positive, 20 diagnosed during pregnancy. Two did not start ART (1 due to miscarriage, 1 as diagnosed post-delivery) and in three cases ART history was unavailable due to transfer to alternative centres. ART was initiated on average at 22 weeks gestation (range 6–34). 4(5%) received Zidovudine (AZT) monotherapy, all before 2006. Choice of combination ART (cART) varied with time reflecting changing guidelines. Prior to 2008 an AZT containing regimen was used in 83% versus 8% after. Planned mode of delivery was documented in 73: 30(41%) planned a normal vaginal delivery (NVD), 43(59%) a caesarean section (CS). The viral load (VL) was?<50 copies/mL in 58(76%) at 36 weeks and 64(84%) at delivery. 90% with a detectable VL at 36 weeks delivered via CS. 100% received neonatal post-exposure prophylaxis (PEP): 68(88%) AZT monotherapy, 9(12%) cART. 84% initiated PEP within four hours. 90% completed 28 days. 8(10%) babies experienced side effects. In the 10-year review period, one infant (1.3%) was diagnosed HIV positive. Both mother and infant received care in accordance with guidelines, including neonatal PEP within 4 hours. Conclusion: Care of the HIV positive pregnant woman in Brighton has been successful with overall transmission consistent with that seen nationally. Despite effective preventative strategies MTCT remains a risk and women should be counselled accordingly

Perioperative critical events and morbidity associated with anesthesia in early life: subgroup analysis of United Kingdom participation in the neonate and children audit of anesthesia practice in Europe (NECTARINE) prospective multicenter observational study

BACKGROUND: The NEonate and Children audiT of Anaesthesia pRactice IN Europe (NECTARINE) prospective observational study reported critical events requiring intervention during 35.2% of 6542 anesthetic episodes in 5609 infants up to 60 weeks postmenstrual age. The United Kingdom (UK) was one of 31 participating countries. METHODS: Subgroup analysis of UK NECTARINE cases (12.8% of cohort) to identify perioperative critical events that triggered medical interventions. Secondary aims were to describe UK practice, identify factors more commonly associated with critical events, and compare 30-day morbidity and mortality between participating UK and non-UK centers. RESULTS: Seventeen UK centers recruited 722 patients (68.7% male, 36.1% born preterm, 48.1% congenital anomalies) undergoing anesthesia for 876 surgical or diagnostic procedures at 25-60 weeks postmenstrual age. Repeat anesthesia/surgery was common: 17.6% patients prior to and 14.4% during the recruitment period. Perioperative critical events triggered interventions in 300/876 (34.3%) cases. Cardiovascular instability (16.9% of cases) and/or reduced oxygenation (11.4%) were more common in younger patients and those with co-morbidities or requiring preoperative intensive support. A higher proportion of UK than non-UK cases were graded as ASA-Physical Status scores >2 or requiring urgent or emergency procedures, and 39% required postoperative intensive care. Thirty-day morbidity (complications in 17.2%) and mortality (8/715, 1.1%) did not differ from non-UK participants. CONCLUSIONS: Perioperative critical events and co-morbidities are common in neonates and young infants. Thirty-day morbidity and mortality data did not demonstrate national differences in outcome. Identifying factors associated with increased risk informs preoperative assessment, resource allocation, and discussions between clinicians and families

Morbidity and mortality after anaesthesia in early life: results of the European prospective multicentre observational study, neonate and children audit of anaesthesia practice in Europe (NECTARINE)

Background: Neonates and infants requiring anaesthesia are at risk of physiological instability and complications, but triggers for peri-anaesthetic interventions and associations with subsequent outcome are unknown. Methods: This prospective, observational study recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. The primary aim was to identify thresholds of pre-determined physiological variables that triggered a medical intervention. The secondary aims were to evaluate morbidities, mortality at 30 and 90 days, or both, and associations with critical events. Results: Infants (n=5609) born at mean (standard deviation [sd]) 36.2 (4.4) weeks postmenstrual age (35.7% preterm) underwent 6542 procedures within 63 (48) days of birth. Critical event(s) requiring intervention occurred in 35.2% of cases, mainly hypotension (&gt;30% decrease in blood pressure) or reduced oxygenation (SpO2 &lt;85%). Postmenstrual age influenced the incidence and thresholds for intervention. Risk of critical events was increased by prior neonatal medical conditions, congenital anomalies, or both (relative risk [RR]=1.16; 95% confidence interval [CI], 1.04-1.28) and in those requiring preoperative intensive support (RR=1.27; 95% CI, 1.15-1.41). Additional complications occurred in 16.3% of patients by 30 days, and overall 90-day mortality was 3.2% (95% CI, 2.7-3.7%). Co-occurrence of intraoperative hypotension, hypoxaemia, and anaemia was associated with increased risk of morbidity (RR=3.56; 95% CI, 1.64-7.71) and mortality (RR=19.80; 95% CI, 5.87-66.7). Conclusions: Variability in physiological thresholds that triggered an intervention, and the impact of poor tissue oxygenation on patient's outcome, highlight the need for more standardised perioperative management guidelines for neonates and infants

Ventilation strategies and risk factors for intraoperative respiratory critical events and postoperative pulmonary complications in neonates and small infants: a secondary analysis of the NECTARINE cohort☆

Background: Optimal ventilation strategies and use of neuromuscular blocking agents (NMBAs) in neonates and small infants undergoing anaesthesia remain unclear. We examined the association of perioperative ventilation strategies and administration of NMBAs on respiratory adverse events in the NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) cohort. Methods: We performed a secondary analysis of NECTARINE, which included infants up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures. The primary endpoint was the association between ventilation mode and intraoperative respiratory adverse events. Secondary endpoints were use of NMBA, and 30-day postoperative pulmonary complications (PPCs). Results: The dataset comprised 5609 patients undergoing 6542 procedures. Pressure-controlled ventilation was the primary ventilation modality, accounting for 52.4% (n=3428) of cases. The incidence of intraoperative respiratory critical events was 20.7% (95% confidence interval [CI] 19.7–21.7%), while PPCs were observed in 17% of cases (95% CI 16.0–18.1%). Preanaesthesia respiratory conditions and NMBA use after tracheal intubation were associated with higher incidence of PPCs. Of the children receiving NMBAs, reversal was reported in 29.8%. The absence of reversal was associated with a higher incidence of PPCs, with a relative risk of 1.50 (95% CI 1.17–1.93). Conversely, NMBA reversal was associated with a reduced relative risk of 0.43 (95% CI 0.26–0.70). Conclusions: Regardless of ventilation strategy used, mechanical ventilation and baseline respiratory conditions were risk factors for a greater incidence of adverse respiratory events and PPCs. Reversal of NMBAs before tracheal extubation was significantly associated with reduced PPCs in neonates and should be routine clinical practice. Clinical trial registration: ClinicalTrials.gov (NCT02350348)