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AIMS Patients with type 2 diabetes mellitus (T2DM) have reduced vasodilatory responses during exercise partially attributable to low nitric oxide (NO) levels. Low NO contributes to greater α-adrenergic mediated vasoconstriction in contracting skeletal muscle. We hypothesized boosting NO bioavailability via 8wks of active beetroot juice (BRA, 4.03 mmol nitrate, 0.29 mmol nitrite, n = 19) improves hyperemia, via reduced α-mediated vasoconstriction, during handgrip exercise relative to nitrate/nitrite-depleted beetroot juice (BRP, n = 18) in patients with T2DM. METHODS Forearm blood flow (FBF) and vascular conductance (FVC) were calculated at rest and during handgrip exercise (20%max, 20contractions·min-1). Phenylephrine (α1-agonist) and dexmedetomidine (α2-agonist) were infused intra-arterially during independent trials to determine the influence of α-mediated vasoconstriction on exercise hyperemia. Vasoconstriction was quantified as the percent-reduction in FVC during α-agonist infusion, relative to pre-infusion, as well as the absolute change in %FVC during exercise relative to the respective rest trial (magnitude of sympatholysis). RESULTS ΔFBF (156 ± 69 to 175 ± 73 ml min-1) and ΔFVC (130 ± 54 to 156 ± 63 ml min-1·100 mmHg-1, both P

The balance of angiogenic factors, including vascular endothelial growth factor (VEGF), and angiostatic factors, like thrombospondin-1 (TSP-1) and endostatin, controls striated muscle angiogenic responses to exercise training. The effect of age on circulating levels of these factors following a bout of exercise is unclear. The authors hypothesized that older adults would have lower circulating VEGF but higher TSP-1 and endostatin after exercise compared with young adults. Ten young and nine older participants cycled for 45 min at 60% estimated HRmax. Serum [VEGF], [TSP-1], and [endostatin] obtained before (PREX), immediately after (POSTX0), and 3 hr after (POSTX3) exercise were analyzed. [VEGF] increased in older adults only from PREX to POSTX0 (p p

Objectives Lung isolation techniques are designed to facilitate surgical exposure in thoracic surgical patients and provide one-lung ventilation (OLV). Some patients have a tracheostomy in situ, which makes the management of the airway and OLV difficult. The objective of this retrospective study was to review cases that had a tracheostomy prior to thoracic surgery and evaluate the clinical use and efficiency with the airway management and lung isolation devices. Design This was a retrospective data analysis. Setting Tertiary care university hospital. Interventions After institutional review board approval, the authors reviewed 3,225 charts of patients who had thoracic surgery involving OLV. Seventy patients were identified who had tracheostomy in situ. Each case was reviewed regarding airway management and lung isolation technique. Measurements and Main Results The authors identified 70 patients who had a tracheostomy in situ. The cases were divided into 2 groups: a fresh tracheostomy stoma 7 days (n = 64). The authors collected information regarding the devices used to manage the airway and lung isolation techniques. The devices used to manage the airway include the Shiley cuffed low pressure tracheostomy tube, single-lumen endotracheal tube (SLT), or double-lumen endotracheal tube (DLT). Devices used to manage OLV included SLTs, with or without bronchial blockers, or DLTs. Flexible fiberoptic bronchoscopy was used to assess the airway and confirm the position of the lung isolation device. Six cases had an early-stage fresh tracheostomy stoma where the Shiley tracheostomy tube was used for ventilation followed by the use of a bronchial blocker. In contrast, for the patients who had a long-term stoma, the following devices were used: (1) a SLT plus a bronchial blocker in 38 cases, a Shiley tracheostomy tube plus bronchial blocker in 15 cases, use of a SLT guided into a selective bronchus in 7 cases, and use of a DLT in 4 cases. In all cases, flexible fiberoptic bronchoscopy was used and no complications occurred secondary to airway management or OLV. Conclusion In patients undergoing thoracic surgery and OLV, and with a fresh tracheostomy stoma in situ, the authors recommend the use of the Shiley tracheostomy tube plus a bronchial blocker. In patients with a long-term tracheostomy stoma, a SLT can be used selectively to intubate 1 bronchus. In addition, an SLT or a Shiley tube can be used in conjunction with an independent bronchial blocker, such as the Arndt wire-guided bronchial blocker, Cohen tip-deflecting blocker, Fuji Uniblocker, or EZ-Blocker. DLTs are the least frequently used device for OLV in tracheostomized patients.

Microvascular endothelial dysfunction precipitates cardiovascular disease mortality in patients with type 2 diabetes mellitus (T2DM). However, the relationship between glycemic management and microvascular endothelial function of these patients remains ill defined. We investigated the association between skeletal muscle microvascular endothelial function with glycemic management (HbA1c) and responses to an oral glucose challenge (OGTT) in 30 patients with T2DM (59 ± 9 years, 31.2 ± 5.1 kg/m2, HbA1c = 7.3 ± 1.3%). On study day 1, microvascular endothelial function was quantified as the increase (Δ from rest) in forearm vascular conductance (FVC, ml/min/100 mmHg) during intra‐arterial acetylcholine infusion at 4.0 and 8.0 μg/dl forearm volume/min (ACh4 and ACh8, respectively). [Glucose] and [insulin] were measured in a fasted state as well as following a 75 g OGTT on a second day with an additional fasting blood sample collected to measure HbA1c. FVC increased (Δ) 221 ± 118 and 251 ± 144 ml/min/100 mm Hg during ACh4 and ACh8 trials, respectively (p 7.0%, respectively. Our data show glycemic management is related to acetylcholine‐mediated vasodilation (e.g., microvascular endothelial function) in skeletal muscle of patients with T2DM., Data in the present study are the first to report an inverse relationship between skeletal muscle microvascular endothelial function and glycemic management (e.g., HbA1c) in patients with type 2 diabetes mellitus (T2DM). Moreover, we found patients who meet the American Diabetes Association's therapeutic target of ≤7.0% HbA1c had greater microvascular endothelial function compared to those >7.0%, yet similar to non‐diabetic controls of similar age, gender, and body mass index. Collectively, we found adequate glycemic management may offset the deleterious effects of diabetes‐induced microvascular dysfunction.

Patients with type 2 diabetes mellitus (T2DM) exhibit diminished exercise capacity likely attributable to reduced skeletal muscle blood flow (i.e., exercise hyperemia). A potential underlying mechanism of the impaired hyperemic response to exercise could be inadequate blunting of sympathetic-mediated vasoconstriction (i.e., poor functional sympatholysis). Therefore, we studied the hyperemic and vasodilatory responses to handgrip exercise in patients with T2DM as well as vasoconstriction to selective α-agonist infusion. Forearm blood flow (FBF) and vascular conductance (FVC) were examined in patients with T2DM (

To estimate strength of a scopolamine transdermal delivery system (TDS) in vivo, using residual drug vs. pharmacokinetic analyses with the goal of scientifically supporting a single and robust method for use across the dosage form and ultimately facilitate the development of more consistent and clinically meaningful labeling. A two-arm, open-label, crossover pharmacokinetic study was completed in 26 volunteers. Serum samples were collected and residual scopolamine was extracted from worn TDS. Delivery extent and rate were estimated by (1) numeric deconvolution and (2) steady-state serum concentration determined from graphical and non-compartmental analyses. In residual drug analyses, mean ± SD scopolamine release rate was 0.015 ± 0.002 mg/h (11% RSD), vs. 0.016 ± 0.006 mg/h (35% RSD) from numeric deconvolution, 0.015 ± 0.005 mg/h (34% RSD) from graphical analysis, and 0.015 ± 0.007 mg/h (44% RSD) from non-compartmental analysis. In residual drug analyses, total drug released was 1.09 ± 0.11 mg (10% RSD), vs. 1.12 ± 0.40 mg (35% RSD) from numeric deconvolution, 1.07 ± 0.35 mg (33% RSD) from graphical analysis, and 1.07 ± 0.45 (42% RSD) from non-compartmental analysis. Extent and rate of scopolamine release were comparable by both approaches, but pharmacokinetic analysis demonstrated greater inter-subject variability.

Blood flow (BF) and vasodilator responses to knee-extension exercise are attenuated in older adults across an exercise transient (onset, kinetics, and steady-state), and reduced nitric oxide bioavailability (NO) has been hypothesized to be a primary mechanism contributing to this attenuation. We tested the hypothesis acute dietary nitrate (NOOlder (n = 10) untrained adults performed single and rhythmic knee-extension contractions at 20% and 40% work-rate maximum (WRAcute ingestion of dietary NOThe key findings of this study are that despite increasing plasma [NO

Objective Selective breeding for desirable traits is becoming popular in aquaculture. In Miyagi prefecture, Japan, a selectively bred population of Coho salmon (Oncorhynchus kisutch) has been established with the original, randomly breeding population maintained separately. Since they have been bred without family records, the genetic diversity within these populations remains unknown. In this study, we estimated the genetic diversity and key quantitative genetic parameters such as heritability and genomic breeding value for body size traits by means of genomic best linear unbiased prediction to assess the genetic health of these populations. Results Ninety-nine and 83 females from the selective and random groups, respectively, were genotyped at 2350 putative SNPs by means of double digest restriction associated DNA sequencing. The genetic diversity in the selectively bred group was low, as were the estimated heritability and prediction accuracy for length and weight (h2 = 0.26–0.28; accuracy = 0.34), compared to the randomly bred group (h2 = 0.50–0.60; accuracy = 0.51–0.54). Although the tested sample size was small, these results suggest that further selection is difficult for the selectively bred population, while there is some potential for the randomly bred group, especially with the aid of genomic information. Electronic supplementary material The online version of this article (10.1186/s13104-018-3663-4) contains supplementary material, which is available to authorized users.

Peripheral artery disease (PAD) is characterized by a reduced blood flow (BF) and an elevated blood pressure (pressor) response during lower extremity exercise. Although PAD is evident in the upper extremities, no studies have determined BF and pressor responses during upper extremity exercise in PAD. Emerging evidence suggests that inorganic nitrate supplementation may serve as an alternative dietary strategy to boost nitric oxide bioavailability, improving exercising BF and pressor responses during exercise. The present study investigated 1) BF and pressor responses to forearm exercise in patients with PAD ( n = 21) relative to healthy age-matched control subjects ( n = 16) and 2) whether 8 wk of NaNO3supplementation influenced BF and pressor responses to forearm exercise in patients with PAD. Patients with moderate to severe PAD were randomly assigned to a NaNO3(1 g/day, n = 13)-treated group or a placebo (microcrystalline cellulose, n = 8)-treated group. Brachial artery forearm BF (FBF; via Doppler) and blood pressure (via finger plethysmography) were measured during mild-intensity (~3.5-kg) and moderate-intensity (~7-kg) handgrip exercise. The absolute change (from baseline) in FBF was reduced (except in the 3.5-kg condition) and BP responses were increased in patients with PAD compared with healthy control subjects in 3.5- and 7-kg conditions (all P < 0.05). Plasma nitrate and nitrite were elevated, exercising (7-kg) ΔFBF was improved (from 141 ± 17 to 172 ± 20 ml/min), and mean arterial pressure response was reduced (from 13 ± 1 to 9 ± 1 mmHg, P < 0.05) in patients with PAD that received NaNO3supplementation for 8 wk relative to those that received placebo. These results suggest that the BF limitation and exaggerated pressor response to moderate-intensity forearm exercise in patients with PAD are improved with 8 wk of NaNO3supplementation.NEW & NOTEWORTHY Peripheral artery disease (PAD) results in an exaggerated pressor response and reduced blood flow during lower limb exercise; however, the effect of PAD in the upper limbs has remained unknown. These results suggest that 8 wk of inorganic nitrate supplementation improves the blood flow limitation and exaggerated pressor response to moderate-intensity forearm exercise in PAD.

Aging is associated with increased peripheral chemoreceptor activity, reduced nitric oxide (NO) bioavailability, and attenuation of cardiovagal baroreflex sensitivity (BRS), collectively increasing the risk of cardiovascular disease. Evidence suggests that NO may attenuate peripheral chemoreflex sensitivity and increase BRS. Exogenous inorganic nitrate ([Formula: see text]) increases NO bioavailability via the [Formula: see text]-[Formula: see text]-NO pathway. Our hypothesis was that inorganic [Formula: see text] supplementation would attenuate peripheral chemoreflex sensitivity and enhance spontaneous cardiovagal BRS in older adults. We used a randomized, placebo-controlled crossover design in which 13 older (67 ± 3 yr old) adults ingested beetroot powder containing (BRA) or devoid of (BRP) [Formula: see text] and [Formula: see text] daily over 4 wk. Spontaneous cardiovagal BRS was assessed over 15 min of rest and was quantified using the sequence method. Chemoreflex sensitivity was assessed via ~5 min of hypoxia (10% fraction of inspired O2) and reported as the slope of the relationship between O2 saturation (%[Formula: see text]) and minute ventilation (in l/min) or heart rate (in beats/min). Ventilatory responsiveness to hypoxia was reduced after BRA (from −0.14 ± 0.04 to −0.05 ± 0.02 l·min−1·%[Formula: see text]−1, P = 0.01) versus BRP (from −0.10 ± 0.05 to −0.11 ± 0.05 l·min−1·%[Formula: see text]−1, P = 0.80), with no differences in heart rate responsiveness (BRA: from −0.47 ± 0.06 to −0.33 ± 0.04 beats·min−1·%[Formula: see text]−1, BRP: from −0.48 ± 0.07 to −0.42 ± 0.06 beats·min−1·%[Formula: see text]−1) between conditions (interaction effect, P = 0.41). Spontaneous cardiovagal BRS was unchanged after BRA and BRP (interaction effects, P = 0.69, 0.94, and 0.39 for all, up, and down sequences, respectively), despite a reduction in resting systolic and mean arterial blood pressure in the experimental (BRA) group ( P < 0.01 for both). These findings illustrate that inorganic [Formula: see text] supplementation attenuates peripheral chemoreflex sensitivity without concomitant change in spontaneous cardiovagal BRS in older adults. NEW & NOTEWORTHY Exogenous inorganic nitrate supplementation attenuates ventilatory, but not heart rate, responsiveness to abbreviated hypoxic exposure in older adults. Additionally, inorganic nitrate reduces systolic and mean arterial blood pressure without affecting spontaneous cardiovagal baroreflex sensitivity. These findings suggest that inorganic nitrate may attenuate sympathetically oriented pathologies associated with aging.

Summary Dynamic ultrasound-guided short-axis needle tip navigation is a novel technique for vascular access. After venipuncture, the needle and catheter are further advanced within the vessel lumen under real-time ultrasound guidance with constant visualisation of the needle tip in the short-axis view. This can minimise the risk of transfixing the cannulated vessel. We compared two techniques for non-visible saphenous vein cannulation under general anaesthesia in children weighing ≥ 3 kg and less than four years of age: dynamic ultrasound-guided short-axis needle tip navigation technique (ultrasound group) vs. landmark technique. Venous cannulation was performed by three experienced anaesthetists. The primary outcome measure was first-attempt success rate. Success rate within 10 min was a secondary outcome. A total of 102 patients were randomly allocated to either the ultrasound group or the landmark group. First-attempt success rate was 90% in the ultrasound group compared with 51% in the landmark group, p

Aging is associated with elevated blood pressure (peripheral and aortic; BP) and aortic augmentation index (AIx) which may contribute to aortic BP. Although inorganic nitrate consumption reduces peripheral BP in both young and older adults, the effects of nitrate consumption on aortic BP and wave reflection in young and older adults is unknown. Therefore, we sought to characterize the effects of nitrate consumption on aortic BP and AIx in young and older adults.Noninvasive aortic pressure waveforms were synthesized from high-fidelity radial pressure waveforms via applanation tonometry before and following (60, 90, 120, 150, and 180 min) consumption of a nitrate-rich beetroot juice in 26 healthy adults (young: 25 ± 4 years, n = 14; older: 64 ± 5 years, n = 12). Aortic BP and indices of aortic wave reflection (AIx and AIx normalized for heart rate; AIx@75bpm) were calculated from the generated aortic pressure waveform.Nitrate consumption increased plasma nitrite in both groups 60-180 min following beetroot consumption (P 0.001). Nitrate consumption reduced peripheral and aortic BP in both young and older adults (P 0.05), with the change being similar between age groups. Conversely, indices of aortic wave reflection were reduced only in young adults following nitrate consumption (range of change from baseline over time: AIx@75bpm, -4.3 to -8.8%, P 0.05), whereas aortic AIx remained unchanged in the older adults.Taken together, our results suggest that acute dietary nitrate supplementation reduces peripheral and aortic BP similarly in young and older adults despite differential effects on aortic AIx between age groups.

With aging, there tends to be an increase in retrograde and oscillatory shear in peripheral conduit arteries of humans. Whether the increase in shear rate is due to the aging process or an effect of a less active lifestyle that often accompanies aging is unknown. Therefore, we examined whether chronic endurance exercise training attenuates conduit artery retrograde and oscillatory shear in older adults.Brachial and common femoral artery mean blood velocities and diameter were determined via Doppler ultrasound under resting conditions, and shear rate was calculated in 13 young (24 ± 2 years), 17 older untrained (66 ± 3 years), and 16 older endurance exercise-trained adults (66 ± 7 years).Brachial artery retrograde (-9.1 ± 6.4 vs. -12.6 ± 9.4 s(-1); P = 0.35) and oscillatory (0.14 ± 0.08 vs. 0.14 ± 0.08 arbitrary units; P = 0.99) shear were similar between the older trained and untrained groups, whereas brachial artery retrograde and oscillatory shear were greater in older untrained compared to young adults (-5.0 ± 3.4, 0.08 ± 0.05 s(-1) arbitrary units, P = 0.017 and 0.048, respectively). There was no difference between the young and older trained brachial retrograde (P = 0.29) and oscillatory (P = 0.07) shear. Common femoral artery retrograde (-6.3 ± 2.9 s(-1)) and oscillatory (0.21 ± 0.08 arbitrary units) shear were reduced in older trained compared to the older untrained group (-10.4 ± 4.1 and 0.30 ± 0.09 s(-1) arbitrary units, both P = 0.005 and 0.006, respectively), yet similar to young adults (-7.1 ± 3.5 and 0.19 ± 0.06 s(-1) arbitrary units, P = 0.81 and 0.87, respectively).Our results suggest that chronic endurance exercise training in older adults ameliorates retrograde and oscillatory shear rate patterns, particularly in the common femoral artery.

This preliminary observational study evaluated a specific ultrasound technique for venous access. Ultrasound was utilized for navigating a needle and catheter within the vessel lumen after venopuncture. One hundred adult obese surgical patients without visible vessels on their upper extremities were enrolled. Forty-five different operators ranging from medical students to attending anesthesia faculty performed venous cannulation with the specific ultrasound technique. Veins in 95 patients were cannulated successfully on the first attempt. This ultrasound-guided protocol facilitates navigation of both the catheter and needle within a vessel, increasing the first-attempt success rate of peripheral venous cannulation in adult obese patients.

Peripheral artery disease (PAD) is characterized by functional and vascular impairments as well as elevated levels of inflammation which are associated with reduced nitric oxide (NO) bioavailability. Inorganic nitrate supplementation boosts NO bioavailability potentially improving functional and vasodilatory capacities and may reduce inflammation. Twenty-one patients with PAD were randomly assigned to sodium nitrate (NaNO(3)) or placebo supplementation groups for eight-weeks. Outcome measures included a six-minute walk test (6MWT), blood flow and vasodilator function in the forearm and calf, as well as plasma inflammatory and adhesion biomarker concentrations. NaNO(3) elevated plasma nitrate (32.3±20.0 to 379.8±204.6μM) and nitrite (192.2±51.8 to 353.1±134.2nM), improved 6MWT performance (387±90 to 425±82m), peak calf blood flow (BF(Peak); 11.6±4.9 to 14.1±5.1mL/dL tissue/min), and peak calf vascular conductance (VC(Peak); 11.1±4.3 to 14.2±4.9mL/dL tissue/min/mmHg) (p

KEY POINTS: Contraction‐mediated blunting of postjunctional α‐adrenergic vasoconstriction (functional sympatholysis) is attenuated in skeletal muscle of ageing males, brought on by altered postjunctional α(1)‐ and α(2)‐adrenergic receptor sensitivity. The extent to which postjunctional α‐adrenergic vasoconstriction occurs in the forearms at rest and during exercise in postmenopausal women remains unknown. The novel findings indicate that contraction‐mediated blunting of α(1)‐ (via intra‐arterial infusion of phenylephrine) but not α(2)‐adrenergic (via intra‐arterial infusion of dexmedetomidine) vasoconstriction was attenuated in postmenopausal women compared to young women. Additional important findings revealed that postjunctional α‐adrenergic vasoconstrictor responsiveness at rest does not appear to be affected by age in women. Collectively, these results contribute to our understanding of local neurovascular control at rest and during exercise with age in women. ABSTRACT: Contraction‐mediated blunting of postjunctional α‐adrenergic vasoconstriction (functional sympatholysis) is attenuated in older males; however, direct confirmation of this effect remains unknown in postmenopausal women (PMW). The present study examined whether PMW exhibit augmented postjunctional α‐adrenergic receptor vasoconstriction at rest and during forearm exercise compared to young women (YW). Eight YW (24 ± 1 years) and eight PMW (65 ± 1 years) completed a series of randomized experimental trials: (1) at rest, (2) under high flow (adenosine infusion) conditions and (3) during 6 min of forearm exercise at relative (20% of maximum) and absolute (7 kg) intensities. Phenylephrine (α(1)‐agonist) or dexmedetomidine (α(2)‐agonist) was administered during the last 3 min of each trial to elicit α‐adrenergic vasoconstriction. Forearm vascular conductance (FVC) was calculated from blood flow and blood pressure. Vasoconstrictor responsiveness was identified as the change in FVC (%) during α‐adrenergic agonist infusions from baseline (resting trial) or from steady‐state conditions (high flow and exercise trials). During resting and high flow trials, the %FVC during α(1)‐ and α(2)‐agonist stimulation was similar between YW and PMW. During exercise, α(1)‐mediated vasoconstriction was blunted in YW vs. PMW at relative (−6 ± 2% vs. −15 ± 3%) and absolute (−4 ± 2% vs. −14 ± 5%) workloads, such that blood flow and FVC were lower in PMW (P 0.05) and absolute (−19 ± 3% vs. ‐18 ± 4%; P > 0.05) workloads. Collectively, these findings demonstrate that despite similar α‐adrenergic vasoconstrictor responsiveness at rest, PMW have a decreased ability to attenuate α(1)‐adrenergic vasoconstriction in contracting skeletal muscle.

Radial arterial cannulation is most commonly done using palpation, but the use of ultrasound has increased the cannulation success rate. This improvement, albeit significant, has not led to a very high success rate especially in trainees. A modified ultrasound technique for vascular cannulation (dynamic needle tip positioning) has been described for peripheral venous cannulation. We therefore assessed the success rate of this technique compared to the palpation technique for radial artery cannulation in adult surgical patients.We enrolled patients who were having nonemergent operations that required a radial arterial catheter for intraoperative monitoring. Patients were randomized to either palpation or dynamic needle tip positioning technique. Arterial cannulation was performed by anesthesia residents or faculty members. The primary end point was successful cannulation on the first pass. Secondary end points were overall 5-minute success rate and number of attempts within 5 minutes.Two hundred sixty patients were evaluated. The first-pass success rate was 83% in the dynamic needle tip positioning technique group (n = 132) and 48% in the palpation group (n = 128; P.001); relative risk was 2.5; 95% confidence interval, 1.7-3.6. The overall 5-minute success rate was 89% in the dynamic needle tip positioning technique group compared to 65% in the palpation group (P.001), relative risk was 2.4; 95% confidence interval, 1.2-1.6. The number of skin puncture attempts was significantly more in the palpation group (P.001). The median cannulation times and interquartile ranges were 81.5 (61-122) seconds in the dynamic needle tip positioning and 76 (48-175) seconds (P = .7) in the palpation group.The use of the ultrasound-guided dynamic needle tip positioning technique increased the first and overall success rates compared to palpation in anesthesia residents and faculty members.

Summary We randomly allocated 749 participants to radial artery cannulation by anaesthetic trainees, guided by Doppler (244), palpation (256) or ultrasound (249). Ultrasound increased the rate of cannulation at the first attempt by 14% (95% CI 5–22%), from 39% with Doppler or palpation, p = 0.002 for both. There were no differences in the rates of cannulation 5 min after the procedure started: 147/244 (60%) with Doppler; 160/256 (63%) with palpation; and 171/249 (69%) with ultrasound, p = 0.13.

Habitual aerobic exercise attenuates elevated vasoconstriction during acute exercise (functional sympatholysis) in older men; however, this effect remains unknown in postmenopausal women (PMW). This study tested the hypothesis that PMW who participate in habitual aerobic exercise demonstrate a greater functional sympatholysis compared with their untrained counterparts. Nineteen PMW (untrained n = 9 vs. trained n = 10) performed 5 min of steady-state (SS) forearm exercise at relative [10% and 20% of maximum voluntary contraction (MVC)] and absolute (5 kg) contraction intensities. Lower-body negative pressure (LBNP) was used to increase sympathetic vasoconstriction during rest and forearm exercise. Brachial artery diameter and blood velocities (via Doppler ultrasound) determined forearm blood flow (FBF; ml/min). Forearm muscle oxygen consumption ([Formula: see text]; ml/min) and arteriovenous oxygen difference (a-vO2diff) were estimated during SS-exercise and SS-exercise with LBNP. Forearm vascular conductance (FVC; ml·min−1·100 mmHg−1) was calculated from FBF and mean arterial pressure (MAP; mmHg). Vasoconstrictor responsiveness was determined as the %change in FVC during LBNP. The reduction in FVC (% change FVC) during LBNP was lower in trained compared with untrained PMW at 10% MVC (−7.3 ± 1.2% vs. −13.0 ± 1.1%; P < 0.05), 20% MVC (−4.4 ± 0.8% vs. −8.6 ± 1.4%; P < 0.05), and 5 kg (−5.3 ± 0.8% vs. −8.9 ± 1.4%; P < 0.05) conditions, whereas there were no differences at rest (−32.7 ± 4.4% vs. −33.7 ± 4.0%). Peripheral (FVC, FBF, and [Formula: see text]) and the magnitude change in systemic hemodynamics (heart rate and MAP) did not differ between groups during exercise. Collectively, the findings present the first evidence suggesting that PMW who participate in aerobic exercise demonstrate a greater functional sympatholysis compared with untrained PMW during mild to moderate forearm exercise. NEW & NOTEWORTHY Habitual aerobic exercise attenuates the elevated sympathetic nervous system-induced vasoconstriction during an acute bout of exercise (improved functional sympatholysis) in aging men; however, this effect remains unknown in postmenopausal women (PMW). The novel findings of this study suggest that habitual aerobic exercise results in an enhanced functional sympatholysis in PMW. Conversely, habitual aerobic exercise does not alter blood flow and oxygen utilization during acute forearm exercise compared with PMW who do not habitually exercise.

Cannulation of the radial artery in infants and small children can be challenging, even for the most experienced providers. Utilizing Doppler to aid in radial artery cannulation has been well described. Recent studies have demonstrated the efficacy of ultrasound (US) image-guided vascular access techniques in the paediatric population. The utility of these two techniques, when used by non-expert personnel, has not been studied.This is a randomized prospective study to compare the utility of two different radial arterial cannulation techniques in paediatric patients weighing12 kg: US-guided technique (US group) vs Doppler-assisted technique (Doppler group) when used by trainees with limited experience. The primary objective was to compare the first-attempt success rate between each group. As a secondary objective, success rate within 10 min was compared.The trial was prematurely terminated after 50% of paediatric patients (n=104) were included in the study and 52 of each were randomized to the US or Doppler group. A total of 12 anaesthesia trainees performed radial arterial cannulations. The first-attempt success rate was greater in the US group compared with the Doppler group [17/52 (33%) vs 8/52 (15%), P=0.039, odds ratio (OR): 2.67, confidence interval (CI): 1.03-6.91]. The overall success rate within 10 min was 34/52 (65%) in the US group and 24/52 (46%) in the Doppler group (P=0.048, OR: 2.20, CI: 1.00-4.85).US-guided radial arterial cannulation in infants and small children provided a greater chance for success at the first attempt compared with the Doppler-assisted technique.

Aging is associated with attenuated contraction-induced rapid onset vasodilation (ROV). We sought to examine whether chronic exercise training would improve ROV in older adults. Additionally, we examined whether a relationship between cardiorespiratory fitness and ROV exists in young and older adults. Chronically exercise-trained older adults ( n = 16; 66 ± 2 yr, mean ± SE) performed single muscle contractions in the forearm and leg at various intensities. Brachial and femoral artery diameter and blood velocity were measured using Doppler ultrasound. Vascular conductance (VC) was calculated as the quotient of blood flow (ml/min) and mean arterial pressure (mmHg). These data were compared with our previously published work from an identical protocol in 16 older untrained (66 ± 1 yr, mean ± SE) and 14 young (23 ± 1 yr) adults. Peak (ΔVCpeak) and total vasodilator (VCtotal) responses were greater in trained compared with untrained older adults across leg exercise intensities ( P < 0.05). There were no differences in responses between trained older and young adults in the arm or leg at any exercise intensity ( P > 0.05). Comparison of ΔVCpeakin a subset of subjects at an absolute workload in the leg revealed that trained older adults exhibited augmented responses relative to untrained older adults. Exercise capacity (V̇o2 peak) was associated with ΔVCpeakand VCtotalacross arm ( r = 0.59–0.64) and leg exercise intensities ( r = 0.55–0.68, P < 0.05) in older adults. Our data demonstrate that 1) chronic exercise training improves ROV in the arm and leg of trained older adults, such that age-related differences in ROV are abolished, and 2) VO2peak is associated with ΔVCpeakresponses in both limbs of older adults.

Background Placement of a percutaneous coronary sinus catheter (CSC) by an anesthesiologist for retrograde cardioplegia in minimally invasive cardiac surgery is relatively safe in experienced hands. However, the popularity of its placement remains limited to a small number of centers due to its perceived complexity and potential complications. Methods We retrospectively reviewed all cardiac cases performed by one surgeon between December 2009 and April 2012. The reviewed cases were divided into two groups: cardiac cases with percutaneous CSC placement (CSC group) and cardiac cases without placement (control group). Anesthesia preparation time (APT) was then compared between the CSC group and control group. In the CSC group, cases were further divided into two groups. One group contained cases with an APT of less than 90 min (success group) and the other contained cases with an APT greater than or equal to 90 min or cases with CSC placement failure (delay/failure group). Patients’ characteristics, type of surgery, and transesophageal echocardiography (TEE) findings were compared between the two groups (success group vs. delay/failure group) to identify variables associated with prolongation of the APT or CSC placement failure. Results Percutaneous CSC placement was required in 83 cases (CSC group). The catheter was successfully placed in 74 of those cases. We experienced one complication, coronary sinus injury after multiple attempts at placing the catheter. The mean APT was 102 ± 31 min in the CSC group (n = 81) and 42 ± 15 min in the control group (n = 285). We could not identify any variables associated with prolongation of the APT or catheter placement failure. Conclusions The success rate of the placement was 89.1 % in our academic center. On average, placing the CSC added approximately one additional hour to the APT. This time is not an accurate representation of true catheter placement time, as it included time for preparation of the CSC, TEE, and fluoroscopy. We experienced one documented complication (coronary sinus injury), which was immediately diagnosed by TEE and fluoroscopy in the operating room. No variables associated with prolongation of APT or CSC placement failure were identified. Electronic supplementary material The online version of this article (doi:10.1186/s12871-016-0203-4) contains supplementary material, which is available to authorized users.

To compare the effectiveness of training with an airway model simulator versus digital video disc (DVD)-based instruction in placement of double-lumen endotracheal (DLT) tubes by anaesthesiologists with limited thoracic experience.Single academic centre parallel randomised controlled trial with computer-generated random allocation.Sixty patients undergoing elective thoracic or oesophageal surgeries requiring one-lung ventilation. Twenty-seven non-thoracic anaesthesiologists were randomised to place a DLT.DLT placement instruction by an interactive airway simulator or computer-based DVD training. The main outcome measure was successful DLT placement.Twenty-seven anaesthesiologists were randomised to one of the two intervention groups. Sixty consecutive patients were assigned to a randomised anaesthesiologist (n = 30 in each group). Participants failed to correctly place or position the DLT tubes in 14 of 60 patients (failure rate of 23%). There was no difference in the probability of satisfactory placement or time for positioning of the DLT between the training groups; 80.5% (95% confidence interval 58.2-96.2%) of tubes were successfully placed following intubation model simulator training versus 73.6% (95% confidence interval 49.8-88.5%) in the DVD group (P = 0.378).Both teaching methods had similar outcomes for placement of DLTs by anaesthesiologists with limited thoracic anaesthesia experience. Both groups performed better than individuals in our prior study. Therefore, these methods should be considered when training anaesthesiologists to successfully place DLTs.

Background In this randomized, double-blind study, the authors compared the effectiveness of a sequential epidural bolus (SEB) technique versus a standard continuous epidural infusion (CEI) technique of local anesthetic delivery. Both techniques used the same hourly dose of local anesthetic. Methods Sixteen gynecologic patients undergoing abdominal surgery received postoperative epidural analgesia using 0.75% ropivacaine at a dose of 22.5 mg (3 ml) per hour. Patients were randomly assigned to one of two groups. In the SEB group (n = 8), patients received one third of the hourly dose every 20 min as a bolus. In the CEI group (n = 8), the hourly dose was administered as a continuous infusion. Analgesia was assessed by rest pain scored by a visual analog scale and pinprick to determine the number of separately blocked spinal segments on each side of the body. Doses of rescue medication for pain were also recorded. Results The median number of blocked spinal segments was 19.5 (range, 18-24) in the SEB group and 11.5 (range, 10-18) in the CEI group (P < 0.001). The median difference in the number of blocked segments between the right and left sides was 0 (range, 0-1) in the SEB group and 2 (range, 0-6) in the CEI group (P < 0.04). No patients in the SEB group but one patient in the CEI group required rescue medication for pain. The visual analog scale pain score was 0 in both groups except for one patient in the CEI group during the study period. Conclusion The SEB technique with ropivacaine provides superior epidural block compared with an identical hourly dose administered as a continuous infusion.

Background Obese patients are at risk of complications during airway management including difficult tracheal intubation. There are no reports regarding the ease of intubation or efficiency of lung collapse with the use of lung isolation devices for the morbidly obese patient. We conducted a prospective, randomized study in morbidly obese patients undergoing one-lung ventilation. We compared the effectiveness and ease of placement of a left-sided double-lumen tube and the Arndt ® blocker. Methods Fifty adult patients undergoing thoracic surgery were randomly assigned to a double-lumen tracheal tube (DLT) or standard single-lumen tracheal tube and an Arndt ® blocker. The primary endpoint was to record the number of times the tube/devices were successfully positioned at the first attempt and the time spent to achieve optimal position as verified by fibreoptic bronchoscopy. A secondary outcome was the adequacy of lung collapse. Results For the left-sided DLT group, there were three intubation failures on the first attempt. This group required an alternative method with an airway exchange catheter technique to advance the DLT. In the single-lumen tracheal tube with an Arndt ® blocker group, there were two intubation failures on the first attempt. After lung isolation devices were placed, lung collapse was clinically comparable in both groups. Conclusions There is no overall advantage of one device over the other during intubation of the morbidly obese patient.

Reduction ascending aortoplasty has been advocated as a possible alternative to traditional graft replacement for treatment of aneurysms of the ascending aorta and root. We report a case of a 58-year-old Jehovah's Witness female, with a 5.5-cm ascending aortic aneurysm and critical aortic stenosis. She underwent aortic valve replacement and reduction aortoplasty buttressed with a Dacron graft. We reviewed the history and contemporary applications of this technique and concluded that aortic reduction with externally supported aortoplasty may represent a viable option to treat Jehovah's Witness patients with ascending aorta and root aneurysm.

We describe the actual state of ruptured de novo intracranial aneurysms to contribute to a guideline of follow-up for the patients with treated intracranial aneurysm.The authors retrospectively investigated 12 cases drawn from 483 consecutive cases of aneurysmal subarachnoid hemorrhage at our institute over a period of 22 years, in which a previously undemonstrated (hence "de novo") intracranial saccular aneurysm formed and ruptured after successful treatment of a prior aneurysm.The 12 cases constitute 2.5% of the 483 patients who left our hospital alive. Eleven cases were females and one was a male with a mean age of 55.7 years (range 29-75) at the first subarachnoid haemorrhage (SAH) and an interval between the first and the second rupture of 10.7 years (range: 2.6-23.8, standard deviation: 6.86, 95% confidence interval: 6.39-15.1). Four cases did not have risk factors such as hypertension, family history, smoking, multiple aneurysms, and moyamoya disease. None of these ruptured de novo aneurysms was at the same location as the original lesion. One-third (4 cases) of the de novo lesions in our series were found on the opposite side to each prior lesion.For not only young but also elder patients with a treated aneurysm (from the fifth decade to the sixth), especially for women, late angiography or alternative modalities of less-invasive examination should be considered. To detect de novo intracranial aneurysms before rupture, the search for a de novo aneurysm should be performed within 6.39 years after a previous examination that shows an aneurysm to be nonexistent, in view of the 95% confidence interval of the mean time to de novo aneurysmal rupture (6.39-15.1 years). If applied this survey, 75% (8 cases of 12 cases) of our de novo aneurysms would be detected before rupture.