Baseline haemoglobin variability by measurement technique in pregnant people on the day of childbirth.

Point-of-care haemoglobin measurement devices may play an important role in the antenatal detection of anaemia in pregnant people and may be useful in guiding blood transfusion during resuscitation in obstetric haemorrhage. We compared baseline haemoglobin variability of venous and capillary HemoCue® haemoglobin, and Masimo® Rad-67 Pulse CO-Oximeter haemoglobin with laboratory haemoglobin in people on the day of their planned vaginal birth. A total of 180 people undergoing planned vaginal birth were enrolled in this prospective observational study. Laboratory haemoglobin was compared with HemoCue and Masimo Rad-67 Pulse CO-Oximeter measurements using Bland-Altman analysis, calculating mean difference (bias) and limits of agreement. Five (2.8%) people had anaemia (haemoglobin < 110 g.l-1 ). Laboratory haemoglobin and HemoCue venous haemoglobin comparison showed an acceptable bias (SD) 0.7 (7.54) g.l-1 (95%CI -0.43-1.79), with limits of agreement -14.10-15.46 g.l-1 and acceptable agreement range of 29.6 g.l-1 . Laboratory and HemoCue capillary haemoglobin comparison showed an unacceptable bias (SD) 13.3 (14.12) g.l-1 (95%CI 11.17-15.34), with limits of agreement - 14.42-40.93 g.l-1 and unacceptable agreement range of 55.3 g.l-1 . Laboratory and Masimo haemoglobin comparison showed an unacceptable bias (SD) -14.0 (11.15) g.l-1 (95%CI -15.63 to -12.34), with limits of agreement to -35.85 to 7.87 g.l-1 and acceptable agreement range of 43.7 g.l-1 . Venous HemoCue, with its acceptable bias and limits of agreement, should be applied more widely in the antenatal setting to detect, manage and risk stratify pregnant people with anaemia. HemoCue capillary measurement under-estimated haemoglobin and Masimo haemoglobin measurement over-estimated, limiting their clinical use. Serial studies are needed to determine if the accuracy of venous HemoCue haemoglobin measurement is sustained in other obstetric settings.

A cross-sectional study of immune seroconversion to SARS-CoV-2 in frontline maternity health professionals.

COVID-19, the respiratory disease caused by SARS-CoV-2, is thought to cause a milder illness in pregnancy with a greater proportion of asymptomatic carriers. This has important implications for the risk of patient-to-staff, staff-to-staff and staff-to-patient transmission among health professionals in maternity units. The aim of this study was to investigate the prevalence of previously undiagnosed SARS-CoV-2 infection in health professionals from two tertiary-level maternity units in London, UK, and to determine associations between healthcare workers' characteristics, reported symptoms and serological evidence of prior SARS-CoV-2 infection. In total, 200 anaesthetists, midwives and obstetricians, with no previously confirmed diagnosis of COVID-19, were tested for immune seroconversion using laboratory IgG assays. Comprehensive symptom and medical histories were also collected. Five out of 40 (12.5%; 95%CI 4.2-26.8%) anaesthetists, 7/52 (13.5%; 95%CI 5.6-25.8%) obstetricians and 17/108 (15.7%; 95%CI 9.5-24.0%) midwives were seropositive, with an overall total of 29/200 (14.5%; 95%CI 9.9-20.1%) of maternity healthcare workers testing positive for IgG antibodies against SARS-CoV-2. Of those who had seroconverted, 10/29 (35.5%) were completely asymptomatic. Fever or cough were only present in 6/29 (21%) and 10/29 (35%) respectively. Anosmia was the most common symptom occurring in 15/29 (52%) seropositive participants and was the only symptom that was predictive of positive seroconversion (OR 18; 95%CI 6-55). Of those who were seropositive, 59% had not self-isolated at any point and continued to provide patient care in the hospital setting. This is the largest study of baseline immune seroconversion in maternity healthcare workers conducted to date and reveals that one out of six were seropositive, of whom one out of three were asymptomatic. This has significant implications for the risk of occupational transmission of SARS-CoV-2 for both staff and patients in maternity units. Regular testing of staff, including asymptomatic staff should be considered to reduce transmission risk.

Persistent or recurrent carpal tunnel syndrome following prior endoscopic carpal tunnel release.

A retrospective review of patients with carpal tunnel syndrome (CTS) identified 20 patients (26 wrists) who had persistent or recurrent CTS after having undergone endoscopic carpal tunnel release (ECTR). Seven wrists never had relief of the original CTS symptoms; for the remaining 19 wrists, the average time to recurrence of CTS following ECTR was 4.8 months. All cases recurred within 12 months from the ECTR. All but 1 patient reported nocturnal pain. All patients experienced morning numbness and stiffness. All wrists had positive Phalen's test results. Once diagnosed with persistent or recurrent CTS, each of the wrists underwent open carpal tunnel release (OCTR). Twenty-two wrists were available for follow-up, with all patients reporting greater satisfaction and relief after the OCTR compared with the ECTR. It is important to recognize that CTS may persist or recur after ECTR. These patients should be treated with OCTR to provide symptomatic relief and prevent the sequelae of ongoing CTS.

Nongenomic regulation of chondrocyte membrane fluidity by 1,25-(OH)2D3 and 24,25-(OH)2D3 is dependent on cell maturation.

1,25-(OH)2D3 and 24,25-(OH)2D3 regulate rat costochondral chondrocyte cultures in a metabolite-specific manner; 1,25-(OH)2D3 targets primarily growth zone cells (GC) and 24,25-(OH)2D3 targets primarily resting zone cells (RC). Some of the effects are nongenomic, since incubation of isolated membrane fractions with the metabolites results in regulation of enzyme activities comparable to that seen in culture. This study examined whether changes in membrane fluidity might be one mechanism involved in the nongenomic regulatory pathway. Chondrocyte cultures were incubated with the vitamin D metabolites and changes in plasma membrane fluidity monitored using the fluorophore, TMA-DPH, which is specific for membranes exposed to external fluids. Isolated matrix vesicles were also incubated directly with the metabolites and anisotropy of the membrane, as well as alkaline phosphatase-specific activity, determined. 1,25-(OH)2D3 caused a rapid and constant increase in alkaline phosphatase-specific activity in GC matrix vesicles; 24,25-(OH)2D3 caused an increase in RC matrix vesicle enzyme activity that was both dose- and time-dependent. Matrix vesicles produced by GC had a lower degree of fluidity than their parent plasma membranes or RC plasma membranes and matrix vesicles. Fluidity of the GC membrane fractions was increased by 1,25-(OH)2D3 in a dose- and time-dependent manner. 1,25-(OH)2D3 had no effect on the fluidity of the RC membranes. 24,25-(OH)2D3 caused a decrease in fluidity in GC at later time points. This metabolite caused an increase in fluidity of RC plasma membranes that returned to normal levels by 6 h; however, the increase induced in the matrix vesicles remained elevated throughout the 24-h experimental period.(ABSTRACT TRUNCATED AT 250 WORDS)

Direct effects of transforming growth factor-beta on chondrocytes are modulated by vitamin D metabolites in a cell maturation-specific manner.

Chondrocytes in the endochondral differentiation pathway produce transforming growth factor-beta (TGF-beta) and response to this growth factor both in vitro and in vivo. To clarify the role that cell maturation state plays in the response, we used a well characterized chondrocyte cell culture model which compares cartilage cells at two different stages of maturation. Confluent fourth passage cultures of rat costochondral resting zone and growth zone cartilage cells were incubated with recombinant human (rh) TGF-beta-1 for 24, 48, or 72 h, and the effect on cell number and [3H]thymidine incorporation was observed. To assess whether TGF-beta regulates chondrocyte differentiation to a calcifying cartilage phenotype, cells were incubated for 24 h with TGF-beta, and the specific activities of alkaline phosphatase and phospholipase A2, two enzymes associated with calcification, were assayed in isolated plasma membranes and matrix vesicles. Alkaline phosphatase-specific activity was also measured in the cell layer. Modulation of TGF-beta action by vitamin D metabolites, also known to regulate endochondral differentiation, was examined. The ability of the chondrocytes to produce latent TGF-beta was assayed. The results show that: 1) quiescent chondrocytes at two stages of endochondral maturation respond to rhTGF-beta-1 by increasing [3H]thymidine incorporation; 2) growth zone cells exhibit no increase in cell number over a 72-h incubation with TGF-beta, whereas resting zone cells exhibit a dose-dependent increase in cell number at 72 h; 3) nonquiescent cells exhibit an increase in alkaline phosphatase-specific activity at 24 h; 4) the effects on this membrane enzyme are comparable in the plasma membranes and matrix vesicles, but the net effect is greater in the extracellular organelle due to the intrinsically higher levels of activity; 5) although differentiation is promoted in resting zone cells, it is limited in the growth zone cells by inhibition of phospholipase A2 activity; and 6) there is a synergistic enhancement of resting zone chondrocyte differentiation when cells are exposed to rhTGF-beta-1 and 24,25-dihydroxyvitamin D3.

Technique for intraduodenal placement of transnasal enteral feeding catheters.

Timely initiation of enteral feeding requires efficient placement of nasoenteric feeding tubes. It is generally agreed that postpyloric placement of feeding tubes reduces the risk of regurgitation and aspiration of feeding formulas. The authors describe a simple, economic method of achieving postpyloric placement of feeding tubes in most patients.