Intra-individual comparison of prostate-specific membrane antigen positron emission tomography/computed tomography versus bone scan in detecting skeletal metastasis at prostate cancer diagnosis.

OBJECTIVES: To compare the diagnostic performance and radiological staging impact of 68 Ga-prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) compared to 99 Tc whole-body bone scan (WBBS) for the detection of skeletal metastasis in the primary staging of prostate cancer (PCa). PATIENTS AND METHODS: A prospective institutional database was retrospectively examined for patients who underwent both PSMA PET and WBBS within a 1 week interval for PCa primary staging. Lesions were categorised as 'negative', 'equivocal', or 'definite' based on nuclear medicine physician interpretation. Metastatic burden was characterised for each imaging modality according to three groups: (i) local disease (no skeletal metastases), (ii) oligometastatic disease (three or fewer skeletal metastases), or (iii) polymetastatic disease (more than three skeletal metastases). RESULTS: There were 667 patients included. The median (interquartile range) prostate-specific antigen level was 9.2 (6.2-16) ng/mL and 60% of patients were high risk according to a modified D'Amico risk classification. The overall distribution of skeletal metastasis detection changed across the two scans overall (P = 0.003), being maintained within high-risk (P = 0.030) and low-risk (P = 0.018) groups. PSMA PET/CT identified more definite skeletal metastases compared to WBBS overall (10.3% vs 7.3%), and according to risk grouping (high: 12% vs 9%, intermediate: 4% vs 1%). Upstaging was more common with PSMA PET/CT than WBBS (P = 0.001). The maximum standardised uptake value (SUVmax ) of the primary tumour was associated with upstaging of skeletal metastases on PSMA PET/CT (P = 0.025), while age was associated with upstaging on WBBS (P = 0.021). The SUVmax of the primary tumour and metastases were both higher according to extent of metastatic disease (P = 0.001 and P < 0.001, respectively). CONCLUSIONS: More skeletal metastases were detected with PSMA PET/CT than WBBS, resulting in a higher upstaging rate mostly in high-risk patients. The SUVmax of the primary tumour and metastases was associated with upstaging.

Finger cuff versus invasive and noninvasive arterial pressure measurement in pregnant patients with obesity.

BACKGROUND: Pregnant patients with obesity may have compromised noninvasive blood pressure (NIBP) measurement. We assessed the accuracy and trending ability of the ClearSight™ finger cuff (FC) with invasive arterial monitoring (INV) and arm NIBP, in obese patients having cesarean delivery. METHODS: Participants were aged ≥18 years, ≥34 weeks gestation, and body mass index (BMI) ≥ 40 kg m-2. FC, INV, and NIBP measurements were obtained across 5-min intervals. The primary outcome was agreement of FC measurements with those of the reference standard INV, using modified Bland-Altman plots. Secondary outcomes included comparisons between FC and NIBP and NIBP versus INV, with four-quadrant plots performed to report discordance rates and evaluate trending ability. RESULTS: Twenty-three participants had a median (IQR) BMI of 45 kg m-2 (44-48). When comparing FC and INV the mean bias (SD, 95% limits of agreement) for systolic blood pressure (SBP) was 16 mmHg (17, -17.3 to 49.3 mmHg), for diastolic blood pressure (DBP) -0.2 mmHg (10.5, -20.7 to 20.3), and for mean arterial pressure (MAP) 5.2 mmHg (11.1, -16.6 to 27.0 mmHg). Discordance occurred in 54 (26%) pairs for SBP, 41 (23%) for DBP, and 41 (21.7%) for MAP. Error grid analysis showed 92.1% of SBP readings in Zone A (no-risk zone). When comparing NIBP and INV, the mean bias (95% limits of agreement) for SBP was 13.0 mmHg (16.7, -19.7 to 29.3), for DBP 5.9 mmHg (11.9, -17.4 to 42.0), and for MAP 8.2 mmHg (11.9, -15.2 to 31.6). Discordance occurred in SBP (84 of 209, 40.2%), DBP (74 of 187, 39.6%), and MAP (63 of 191, 33.0%). CONCLUSIONS: The FC and NIBP techniques were not adequately in agreement with INV. Trending capability was better for FC than NIBP. Clinically important differences may occur in the setting of the perfusion-dependent fetus.

Nutrition outcomes and treatment toxicities in patients with head and neck cancer receiving helical intensity-modulated radiotherapy.

BACKGROUND: Helical intensity-modulated radiotherapy (H-IMRT) provides excellent limitation of dose to tissues not requiring treatment, although acute toxicity still occurs. The present study aimed to determine how treatment-related acute toxicities affect nutrition outcomes in patients with head and neck cancer. METHODS: A prospective observational study was conducted in 194 patients undergoing curative intent H-IMRT with or without other treatment modalities. Weight outcomes (kg) and acute toxicity and dysphagia data were collected during treatment using Common Toxicity Criteria for Adverse Effects (CTCAE), version 4.0. RESULTS: Significant weight loss (> 10%) was observed in 30% of high nutritional risk patients and 7% of low nutritional risk patients. Nausea, adjusted for baseline dysphagia, in high nutritional risk patients and nausea, dysphagia and pharyngeal mucositis in low nutritional risk patients were significant factors in explaining the percentage loss in baseline weight to treatment completion. CONCLUSIONS: Significant weight loss remains an issue during treatment, despite improvements in radiotherapy technology and high-level multidisciplinary care.

Effect of supplements/intensive nutrition on pressure ulcer healing: a multicentre, randomised controlled study.

OBJECTIVE: To investigate the effectiveness of an intensive nutrition intervention or use of wound healing supplements compared with standard nutritional care in pressure ulcer (PU) healing in hospitalised patients. METHOD: Adult patients with a Stage II or greater PU and predicted length of stay (LOS) of at least seven days were eligible for inclusion in this pragmatic, multicentre, randomised controlled trial (RCT). Patients with a PU were randomised to receive either: standard nutritional care (n=46); intensive nutritional care delivered by a dietitian (n=42); or standard care plus provision of a wound healing nutritional formula (n=43). Relevant nutritional and PU parameters were collected at baseline and then weekly or until discharge. RESULTS: Of the 546 patients screened, 131 were included in the study. Participant mean age was 66.1±16.9 years, 75 (57.2%) were male and 50 (38.5%) were malnourished at recruitment. Median length of stay was 14 (IQR: 7-25) days and 62 (46.7%) had ≥2 PUs at the time of recruitment. Median change from baseline to day 14 in PU area was -0.75cm2 (IQR: -2.9_-0.03) and mean overall change in Pressure Ulcer Scale for Healing (PUSH) score was -2.9 (SD 3.2). Being in the nutrition intervention group was not a predictor of change in PUSH score, when adjusted for PU stage or location on recruitment (p=0.28); it was not a predictor of PU area at day 14, when adjusted for PU stage or area on recruitment (p=0.89) or PU stage and PUSH score on recruitment (p=0.91), nor a predictor of time to heal. CONCLUSION: This study failed to confirm a significant positive impact on PU healing of use of an intensive nutrition intervention or wound healing supplements in hospitalised patients. Further research that focuses on practical mechanisms to meet protein and energy requirements is needed to guide practice.

Prospective intra-individual blinded comparison of [18F]PSMA-1007 and [68 Ga]Ga-PSMA-11 PET/CT imaging in patients with confirmed prostate cancer.

INTRODUCTION: [18F]PSMA-1007 has potential advantages over [68 Ga]Ga-PSMA-11, although limited prospective data evaluating diagnostic performance exist. The aims of this study are to describe the concordance of [18FPSMA-1007 and [68 Ga]Ga-PSMA-11 for TNM with the American Joint Committee on Cancer (AJCC) prognostic stage and assess differences in tracer uptake. METHODS: Fifty men (mean age 71.8) were imaged with [68 Ga]Ga-PSMA-11 and [18F]PSMA-1007 < 4 weeks apart. Images were independently reported according to TNM by two experienced nuclear medicine specialists blinded to the other scan and prior imaging. Discordant results were resolved by a third independent nuclear medicine specialist. Quantitative analysis of lesion uptake and physiologic tissue for each tracer was performed by one experienced reader. RESULTS: Scan indications were initial staging (n = 12), biochemical recurrence (n = 27) and metastatic disease evaluation (n = 11). Most patients had ISUP grade group 3 or higher. Median PSA value was 2.7 ng/ml (IQR 0.7-12.0), and a minority of patients (28%) were currently treated with androgen deprivation therapy. [18F]PSMA-1007 uptake was significantly higher than [68Ga]Ga-PSMA-11 in local recurrence, nodal and distant metastases and most physiologic sites (including bone) except for urinary bladder which was significantly lower. [18F]PSMA-1007 upstaged local prostate staging in 5/17 patients, local recurrence in 3/33 patients, regional nodal disease in 3/50 patients and 1 distant metastasis (bladder). [68Ga]Ga-PSMA-11 upstaged regional nodal disease in 1/50 patients and distant metastasis in one patient (right adrenal). Overall AJCC prognostic stage was concordant in 46/50 (92%) patients, with two patients upstaged for both [18F]PSMA-1007 and [68Ga]Ga-PSMA-11. [18F]PSMA-1007 had more equivocal results (one regional node; six equivocal bone lesions, one of which was subsequently confirmed metastatic) than [68Ga]Ga-PSMA-11 (one equivocal local recurrence). CONCLUSION: Overall AJCC prognostic stage was similar (92%) between [18F]PSMA-1007 and [68Ga]Ga-PSMA-11. [18F]PSMA-1007 demonstrates higher uptake within involved nodes and distant metastases and most physiologic sites except urinary bladder which aided [18F]PSMA-1007 local staging of the prostate primary/local recurrence and regional nodal disease adjacent ureters. However, [18F]PSMA-1007 liver uptake obscured a solitary right adrenal metastasis, and more equivocal bone lesions were identified. Trial registration The study was registered with Australia New Zealand Clinical Trials Registry (ACTRN12618000665235) on 24 April 2018.

The effect of transnasal humidified rapid-insufflation ventilator exchange (THRIVE) versus nasal prongs on safe apnoea time in paralysed obese patients: a randomised controlled trial.

BACKGROUND: Evidence is lacking regarding the efficacy of Optiflow transnasal humidified rapid-insufflation ventilator exchange (THRIVE™) in obese patients. We compared the impact of this technique at 70 L min-1 with 4 L min-1 oxygen via nasal prongs on safe apnoea times of paralysed obese patients. METHODS: We randomised adults with a BMI >35 kg m-2 undergoing elective bariatric surgery. While apnoeic and paralysed, Group T received 70 L min-1 oxygen via Optiflow THRIVE™. Group N received nasal prong oxygen at 4 L min-1. The primary outcome was time to SpO2 ≤95% while apnoeic, with a 360 s cut-off. This was analysed by applying a time-to-event analysis. RESULTS: Forty-two patients were included. The median (inter-quartile range) BMI was 44.8 kg m-2 (40.0-50.0) in Group T and 42.0 kg m-2 (39.3-45.1) in Group N. Median (inter-quartile range) time to SpO2 ≤95% in Group T was 356 (165 to ≥360) s and in Group N, 210 (160-270) s. Using a survival analysis framework, median time-to-event in Group T was 356 s (95% confidence interval 165 s-upper limit not defined) and 210 s (95% confidence interval 160-242 s) (P=0.049) in Group N. CONCLUSIONS: Compared with oxygen delivered via nasal prongs at 4 L min-1, oxygen delivery via Optiflow THRIVE™ at a flow rate of 70 L min-1 can prolong safe apnoea time, however, the results are statistically inconclusive. Optiflow THRIVE™ did decrease the rate of reduction in Pao2 during apnoea. CLINICAL TRIAL REGISTRATION: ANZCTR 12618000445279.

The prevalence of subthreshold psychiatric symptoms and associations with alcohol and substance use disorders: from a nationally representative survey of 36,309 adults.

BACKGROUND: Our aim was to describe a broad number of subthreshold psychiatric symptoms (SPS) in a nationally representative population and evaluate associations with substance use. SPS describe groups of symptoms with significant pathology, but that do not quite meet full psychiatric diagnostic criteria. They have been associated with significant impairment and cost. METHODS: The National Epidemiologic Survey on Alcohol and Related Conditions-III was a multistage, weighted, cross-sectional survey completed in the United States in 2013 comprising 36,309 noninstitutionalized adults. We report lifetime prevalence rates of 14 SPS related to mood, anxiety, trauma, eating, and personality disorders. We then evaluate associations with lifetime alcohol use disorders (AUD) and all substance use disorders (SUD) using logistic regression and adjusted odds ratios. SPS and psychiatric diagnoses were mutually exclusive (could not co-occur). RESULTS: Lifetime prevalence of having at least one of 14 SPS was 57% compared with 37% for the related psychiatric disorders. This was similar for males and females, in contrast to psychiatric disorders in which prevalence was 42% in females and 31% in males. Otherwise, overall SPS and disorders had similar prevalence patterns across sociodemographic characteristics. Subthreshold personality symptoms had the highest prevalence rates (schizotypal 21.3%, antisocial 18.3%, and borderline 17.6%), followed by posttraumatic stress (13.1%). Subthreshold bipolar and depression had lifetime prevalence rates of 2.7 and 8.5%, respectively. Prevalence rates of subthreshold anxiety symptoms ranged from 2.2% (agoraphobia) to 9.8% (specific phobia). Subthreshold eating disorder related symptoms had the lowest prevalence rates (anorexia 1.5% and bulimia 1.7%). Half (seven) of the SPS had significantly increased odds of lifetime AUD. This number increased to 12 for all SUD. Subthreshold antisocial personality symptoms had the highest odds of AUD (2.2; 95% CI 2.00-2.37) and SUD (3.5; 95% CI 3.22-3.81). CONCLUSIONS: We found high lifetime SPS prevalence rates and significant associations with AUD and SUD. To our knowledge, this is the first published study evaluating a broad number of SPS. This indicates possible opportunities for early intervention and prevention but requires additional research and development of infrastructure and guidelines to better understand and manage patients who experience SPS.

The association between birth by caesarean section at term and offspring cognitive and academic performance: A birth cohort study.

BACKGROUND: Caesarean section (CS) is associated with an increased risk of adverse health outcomes for both mothers and offspring. The evidence for an association between CS and reduced offspring cognitive and academic performance has been inconsistent, with considerable limitations. AIM: The aim of this study is to compare cognitive and academic performance in childhood and early adulthood in offspring delivered by CS with those delivered vaginally at term. MATERIALS AND METHODS: Data on 4327 mothers and offspring from a longitudinal birth cohort study were analysed. Offspring cognitive performance was measured by the Picture Peabody Vocabulary Test-Revised (PPVT-R) at ages five and 21 and the Raven's Standard Progressive Matrices at age 14. Academic achievement was assessed using the Wide Range Achievement Test at age 14. RESULTS: After adjustment for confounding factors, there was no statistically significant association between cognitive performance and offspring birth mode at age five (P = 0.11). The adjusted difference of mean scores at five years on the PPVT-R for elective CS birth compared to those born by vaginal delivery was -2.2 (95% confidence interval (CI) -4.3 to -0.2), whereas for emergency CS it was 0.0 (95% CI -2.0 to 2.0). There were no differences in cognitive or academic performance at ages 14 and 21. CONCLUSION: Birth mode was not significantly associated with offspring cognitive or academic performance. Our study does not support concerns that CS is associated with a reduction in cognitive performance.

Attitudes and awareness of Australian women regarding peripartum antibiotic use: A multicentre survey.

BACKGROUND: Peripartum antibiotics are commonly administered. Little is known of the attitudes of pregnant women toward peripartum antibiotics. AIM: We aimed to assess the awareness of and attitudes toward peripartum antibiotic use in Australian women. MATERIALS AND METHODS: We surveyed post-partum women at three hospitals over six months. Women reported if they received antibiotics 48 h either side of delivery and responded to statements assessing attitudes to peripartum antibiotic use. Administered antibiotics were recorded. We reported the proportion receiving antibiotics and the proportion aware of receiving them. Participants responded on five-point Likert scales and selected side effects of concern. RESULTS: Participants responding were 248 of 299 (83%, Royal Brisbane and Women's Hospital), 56 of 106 (53%, Caboolture Hospital) and 17 (Redcliffe Hospital, denominator not recorded). Of 183 (57%) receiving antibiotics, 134 (73%) received them pre-delivery only, 18 (10%) post-delivery only and 31 (17%) pre- and post-delivery. Pre-delivery, the most common indication was pre-incisional prophylaxis for caesarean delivery (93 of 160 responses, 58%). Seventy-nine (51%, 156 responses) of those receiving pre-delivery antibiotics were aware. Of 49 women receiving post-delivery antibiotics, 36 (73%) were aware. Most agreed they were worried that pre-delivery antibiotics would affect their baby (198, 62%) and 160 (50%) were concerned about effects on their own microbiome. Most (204, 65%) agreed they would rather not take antibiotics while breastfeeding. CONCLUSION: Many women were unaware of receiving pre-delivery antibiotics. Most had concerns about side effects. Improved communication regarding peripartum antibiotic use would improve patient-centred care.

Single-centre survey of women reflecting on recent experiences and preferences of oral intake during labour.

BACKGROUND: Consensus-based recommendations guiding oral intake during labour are lacking. AIMS: We surveyed women at a tertiary women's hospital about preferences for and experiences of oral intake during labour, gastrointestinal symptoms during labour and recalled advice about oral intake. MATERIALS AND METHODS: Women who experienced labour completed a postpartum survey with responses as free text, yes-no questions and five-point Likert scales. We identified demographic data and risk factors for surgical or anaesthetic intervention at delivery from medical records. We summarised free text comments using conventional content analysis. RESULTS: One hundred and forty-nine women completed the survey (47% response rate). Their mean (SD) age was 31 (four) years, birthing at median gestation of 39 weeks (interquartile range: 38-40). One hundred and twenty-two (83%) and 44 (30%) women strongly agreed or agreed they felt like drinking and eating respectively during labour. Ninety women (61%) reported nausea and 47 women (32%) reported vomiting in labour. Forty-one women (28%) did not receive advice on oral intake during labour. Maternal risk factors for surgical intervention were identified in 72 (48%) women and fetal risk factors in 27 (18%) women. Thirty-one women (21%) delivered by emergency caesarean section. CONCLUSION: Pregnant women received variable advice regarding oral intake during labour, from variable sources. Most women felt like drinking but not eating during labour. Guidelines on oral intake in labour may be beneficial to women, balancing the preferences of women with risks of surgical intervention.

Polyhexamethylene biguanide discs versus unmedicated dressings for prevention of central venous catheter-associated infection in the intensive care unit: A pilot randomised controlled trial to assess protocol safety and feasibility.

BACKGROUND: Central venous catheters are prone to infectious complications, affecting morbidity, mortality and healthcare costs. Polyhexamethylene biguanide-impregnated discs at the catheter insertion site may prevent local and bloodstream infection; however, efficacy has not been established in a critical care setting. OBJECTIVE: The objective of this study was to pilot test polyhexamethylene biguanide-impregnated discs compared to standard unmedicated dressings for central venous catheter infection prevention in critically ill patients. METHODS: This was a single-centre pilot randomised controlled trial. Adults admitted to intensive care requiring a central venous catheter for >72 h were eligible. Patients with a current bloodstream infection, concurrent central venous catheter, chlorhexidine or polyhexamethylene biguanide allergy, or sensitive skin were excluded. Patients were randomised to receive standard central venous catheter dressings with/without polyhexamethylene biguanide discs. OUTCOME MEASURES: The primary outcome was feasibility, defined by patient eligibility, recruitment, retention, protocol adherence, missing data, and staff satisfaction. Secondary outcomes included: central line-associated infection; primary bloodstream infection; local infection; skin complications; device/dressing dwell time; serious adverse events, and cost-effectiveness. RESULTS: Of 309 patients screened, 80 participants were recruited with 98% (n = 78) receiving an internal jugular catheter which dwelled for a median of 5 days (interquartile range = 4.0, 6.0). Feasibility criteria were predominantly met (recruitment 88%; retention 100%; protocol fidelity 91%); however, eligibility criteria were not met (32%; most commonly owing to short predicted catheter dwell). Staff acceptability criteria were met, with 83% of staff scoring dressing application and removal ≥7 on a numerical rating scale. There were no central line-associated bloodstream infections and no local infections. Insertion site itch occurred in 4% (control [n = 0], intervention [n = 3]) of participants, while 32% (24/76) reported pain, and 46% (35/76) tenderness. CONCLUSIONS: Polyhexamethylene biguanide discs appear safe for central venous catheter infection prevention. Feasibility of a large efficacy trial was established with some modifications to screening processes. Large, adequately powered randomised controlled trials are needed to test the infection prevention hypotheses.

Clinical insignificance of [18F]PSMA-1007 avid non-specific bone lesions: a retrospective evaluation.

PURPOSE: [18F]PSMA-1007 offers advantages of low urinary tracer excretion and theoretical improved spatial resolution for imaging prostate cancer. However, non-specific bone lesions (NSBLs), defined as mild to moderate focal bone uptake without a typical morphological correlate on CT, are a common finding on [18F]PSMA-1007 PET/CT. The purpose of this study was to investigate the clinical outcomes of patients with [18F]PSMA-1007 avid NSBLs, to determine whether patients with NSBLs represent a higher risk clinical cohort, and to determine whether SUVmax can be used as a classifier of bone metastasis. METHODS: A retrospective audit of 214 men with prostate cancer was performed to investigate the clinical outcomes of [18F]PSMA-1007 avid NSBLs according to defined criteria. We also compared the serum PSA, Gleason score, and uptake time of patients with [18F]PSMA-1007 avid NSBLs to patients without [18F]PSMA-1007 avid bone lesions. Finally, we analysed an SUVmax threshold to identify bone metastases using ROC curve analysis. RESULTS: Ninety-four of 214 patients (43.9%) demonstrated at least one NSBL. No [18F]PSMA-1007 avid NSBLs met criteria for a likely malignant or definitely malignant lesion after a median 15.8-month follow-up interval (11.9% definitely benign, 50.3% likely benign, and 37.7% equivocal). There were no statistically significant differences in serum PSA, Gleason score, and uptake time between patients with [18F]PSMA-1007 avid NSBLs and those without [18F]PSMA-1007 avid bone lesions. All NSBLs with adequate follow-up had SUVmax ≤ 11.1. The value of the highest SUVmax distinguished between NSBLs and definite prostate cancer bone metastases, whereby an SUVmax threshold of ≥ 7.2 maximized the Youden's index. CONCLUSION: [18F]PSMA-1007 avid NSBLs rarely represent prostate cancer bone metastases. When identified in the absence of definite metastatic disease elsewhere, it is appropriate to classify those with SUVmax < 7.2 as likely benign. NSBLs with SUVmax 7.2-11.1 may be classified as equivocal or metastatic, with patient clinical risk factors, scan appearance, and potential management implications used to guide interpretation.

The Effect of High-Flow Nasal Oxygen on Carbon Dioxide Accumulation in Apneic or Spontaneously Breathing Adults During Airway Surgery: A Randomized-Controlled Trial.

BACKGROUND: High-flow nasal oxygen (HFNO) is an emerging technology that has generated interest in tubeless anesthesia for airway surgery. HFNO has been shown to maintain oxygenation and CO2 clearance in spontaneously breathing patients and is an effective approach to apneic oxygenation. Although it has been suggested that HFNO can enhance CO2 clearance during apnea, this has not been established. The true extent of CO2 accumulation and resulting acidosis using HFNO during prolonged tubeless anesthesia remains undefined. METHODS: In a single-center trial, we randomly assigned 20 adults undergoing microlaryngoscopy to apnea or spontaneous ventilation (SV) using HFNO during 30 minutes of tubeless anesthesia. Serial arterial blood gas analysis was performed during preoxygenation and general anesthesia. The primary outcome was the partial pressure of CO2 (Paco2) after 30 minutes of general anesthesia, with each group compared using a Student t test. RESULTS: Nineteen patients completed the study protocol (9 in the SV group and 10 in the apnea group). The mean (standard deviation [SD]) Paco2 was 89.0 mm Hg (16.5 mm Hg) in the apnea group and 55.2 mm Hg (7.2 mm Hg) in the SV group (difference in means, 33.8; 95% confidence interval [CI], 20.6-47.0) after 30 minutes of general anesthesia (P < .001). The average rate of Paco2 rise during 30 minutes of general anesthesia was 1.8 mm Hg/min (SD = 0.5 mm Hg/min) in the apnea group and 0.8 mm Hg/min (SD = 0.3 mm Hg/min) in the SV group. The mean (SD) pH was 7.11 (0.04) in the apnea group and 7.29 (0.06) in the SV group (P < .001) at 30 minutes. Five (55%) of the apneic patients had a pH <7.10, of which the lowest measurement was 7.057. No significant difference in partial pressure of arterial O2 (Pao2) was observed after 30 minutes of general anesthesia. CONCLUSIONS: CO2 accumulation during apnea was more than double that of SV after 30 minutes of tubeless anesthesia using HFNO. The use of robust measurement confirms that apnea with HFNO is limited by CO2 accumulation and the concomitant severe respiratory acidosis, in contrast to SV. This extends previous knowledge and has implications for the safe application of HFNO during prolonged procedures.

ClearSight™ finger cuff versus invasive arterial pressure measurement in patients with body mass index above 45 kg/m2.

BACKGROUND: Measuring blood pressure in patients with obesity is challenging. The ClearSight™ finger cuff (FC) uses the vascular unloading technique to provide continuous non-invasive blood pressure measurements. We aimed to test the agreement of the FC with invasive radial arterial monitoring (INV) in patients with obesity. METHODS: Participants had a body mass index (BMI) ≥45 kg/m2 and underwent laparoscopic bariatric surgery. FC and INV measurements were obtained simultaneously every 5 min on each patient, following induction of anesthesia. Agreement over time was assessed using modified Bland-Altman plots and error grid analysis permitted clinical interpretation of the results. Four-quadrant plots allowed assessment of concordance in blood pressure changes. RESULTS: The 30 participants had a median (IQR) BMI of 50.2 kg/m2 (IQR 48.3-55.3). The observed bias (SD, 95% limits of agreement) for systolic blood pressure (SBP) was 14.3 mmHg (14.1, -13.4 - 42.0), 5.2 mmHg (10.9, -16.0 - 26.5) for mean arterial pressure (MAP) and 2.6 mmHg (10.8, -18.6 - 23.8) for diastolic blood pressure (DBP). Error grid analysis showed that the proportion of readings in risk zones A-E were 90.8, 6.5, 2.7, 0 and 0% for SBP and 91.4, 4.3, 4.3, 0 and 0% for MAP, respectively. Discordance occurred in ≤8% of pairs for consecutive change in SBP, MAP and DBP. CONCLUSIONS: The vascular unloading technique was not adequately in agreement with radial arterial monitoring. Evaluation in a larger sample is required before recommending this technique for intraoperative monitoring of patients with BMI ≥45 kg/m2.

Upper limb dimensions in adults presenting for elective surgery - implications for blood pressure measurement.

BACKGROUND: Arm conicity is associated with non-invasive blood pressure (NIBP) measurement error and may be avoided by using finger cuffs. Predicting arm conicity may help decisions regarding NIBP measurement techniques. METHODS: We obtained upper limb measurements of adults presenting to the Pre-Anesthetic Clinic to determine: the suitability of arm and finger cuff sizes; the best anthropometric predictor of arm conicity based on the right arm slant angle; the incidence of a right arm slant angle < 83 degrees. Right mid-arm circumference (MAC) was compared to recommended cuff sizes and finger circumference compared to available cuffs. Slant angle was calculated from the measurements obtained. Linear regression was used to determine the better predictor of right arm slant angle. Correlation coefficients were calculated and R2 values compared. RESULTS: Four hundred fifty-four patients participated and 453 had cone-shaped arms. One participant (0.2, 95% CI 0.0-1.2) had a MAC outside the recommended cuff range. Twenty-five participants (5.5, 95% CI 3.6-8.0) had a middle finger circumference greater than the largest ClearSight™ cuff. Body mass index (BMI), weight and right MAC all had low to moderate correlation with right arm slant angle (r = - 0.49, - 0.39, - 0.48, all p < 0.001) and regression revealed R2 values of 0.24, 0.15 and 0.23. Six participants (1.3, 95% CI 0.5-2.9) had a slant angle < 83 degrees. CONCLUSION: Current NIBP equipment caters for most patients, based on the traditional measure of MAC. The utility of finger cuffs is limited by cuff size. BMI and right MAC showed the most promise in predicting arm conicity.

A prospective randomized comparison of airway seal using the novel vision-guided insertion of LMA-Supreme® and LMA-Protector®.

The laryngeal mask airways supreme (LMA-Supreme™) and protector (LMA-Protector™) are generally placed blindly, often resulting in a less than optimal position and vision-guided placement has been recommended. This prospective, randomized controlled study compared the efficacy of airway seal by measuring the oropharyngeal leak pressure in 100 surgical patients who underwent a variety of non-thoracic surgery under general anaesthesia, suitable with a supraglottic airway device. Patients were allocated to either the LMA-Supreme (n = 50) or LMA-Protector (n = 50) group. All insertions were performed under vision of a videolaryngoscope using an 'insert-detect-correct-as-you-go' technique with standardized corrective measures. Our primary endpoint, mean oropharyngeal leak pressure, was significantly higher in the LMA-Protector (31.7 ± 2.9 cm H2O) compared to the LMA-Supreme (27.7 ± 3.5 cm H2O) group (mean difference 4.0 cm H2O, 95% confidence interval (CI) 2.7-5.3 cm H2O, p < 0.001) after achieving a near-optimal fibreoptic position in the LMA-Protector (94%) and LMA-Supreme (96%) groups. No statistically significant differences were shown for secondary outcomes of alignment, number of insertion attempts and malpositions, and final anatomical position as scored by fibreoptic evaluation. Corrective manoeuvres were required in virtually all patients to obtain a correct anatomically positioned LMA. Position outcomes of the two devices were similar except for the proportion of procedures with folds in the proximal cuff (90% LMA-Supreme vs. 2% LMA-Protector, p < 0.001), the need for intracuff pressure adjustments (80% LMA-Supreme vs. 48% LMA-Protector, p = 0.001) and size correction (18% LMA-Supreme vs. 4% LMA-Protector, p = 0.025). In conclusion, a higher oropharyngeal leak pressure can be achieved with LMA-Protector compared to LMA-Supreme with optimal anatomical position when insertion is vision-guided.

Radiotherapy for cutaneous head and neck cancer and parotid tumours: a prospective investigation of treatment-related acute swallowing and toxicity patterns.

PURPOSE: Reports of acute treatment-related dysphagia and toxicities for patients with parotid tumours or cutaneous head and neck cancer (HNC) are limited. This study aimed to describe the severity and timing of dysphagia and related toxicities experienced during radiotherapy for cutaneous HNC and parotid tumours, to inform the nature of future speech pathology (SP) service models required during treatment. METHODS: Prospective study of 32 patients with parotid tumours and 36 with cutaneous HNC undergoing curative non-surgical management. Dysphagia and acute toxicity data was collected weekly during treatment and at 2, 4 and 12 weeks post-treatment using the Functional Oral Intake Scale, diet descriptors and CTCAE v4.0. RESULTS: In both groups, minimal treatment toxicities (grades 0-1) were observed. Xerostomia and dysgeusia were the most frequently reported grade 2 toxicities. Only 3% of parotid patients and 6% with cutaneous HNC experienced grade 3 dysphagia. Full or soft texture diets were maintained by > 70% of patients in both groups. Symptoms peaked in the final week of treatment and rapidly improved thereafter. Apart from xerostomia < 10% of patients had any grade 2 toxicity at 12 weeks post-treatment. CONCLUSION: Patients in these subgroups of HNC experienced minimal treatment-related toxicity during radiotherapy. As such, the need for supportive symptom management by SP is low. Models that involve interdisciplinary surveillance of symptoms with referral to SP only when required may be best suited for these individuals to ensure issues are identified whilst minimising patient burden created by unnecessary routine SP appointments.

The feasibility of a clinical audit tool to investigate stillbirth in Australia - a single centre experience.

BACKGROUND: The stillbirth rate in Australia is 7 per 1000 births (Australia's Mothers and Babies 2014-in brief. Perinatal Statistics Series no. 32. Cat no. PER 87, Canberra, AIHW, 2016). The Perinatal Society of Australia and New Zealand (PSANZ) developed guidelines to standardise the investigations into stillbirth. AIMS: To identify causes of stillbirths and stillbirth care using the National Perinatal Death Clinical Audit Tool (National Perinatal Death Clinical Audit Tool, Australian and New Zealand Stillbirth Alliance [ANZSA]/Perinatal Society of Australia and New Zealand [PSANZ]) and compare it to the PSANZ recommendations. Documentation of examination findings and follow-up after stillbirth were also reviewed. MATERIALS AND METHODS: From the total of 515 registered stillbirths at a Queensland hospital, 170 stillbirths were considered unexplained after chart review between July 2004 and September 2014. The National Perinatal Death Clinical Audit Tool was applied and resulting underlying causes of stillbirths were classified using the PSANZ perinatal mortality classification system. RESULTS: The stillbirth rate for this centre was 11.2 per 1000 births. A cause of fetal death was established in 55.4% (93/168) and 75 cases (44.6%) remained unexplained corresponding to 14.6% of all registered stillbirths (75/515). Over half of the women (52.7%) were nulliparous. High rates of autopsy (47.3%), bereavement support (99.4%) and placental histopathology (98.8%) were noted. The general practitioner was notified in 98.7% of cases at the time of stillbirth; 34.1% of babies were small for gestational age at birth, 18.9% were growth-restricted at birth and 21.4% of women were current smokers. CONCLUSION: The National Perinatal Death Clinical Audit Tool facilitates and streamlines stillbirth investigations and thus helps to identify underlying causes of stillbirth.

Factors associated with infants receiving their mother's own breast milk on discharge from hospital in a unit where pasteurised donor human milk is available.

AIM: To determine the proportion of very preterm infants who were exclusively fed breast milk at the time of discharge home, before and after the availability of pasteurised donor human milk (PDHM). METHODS: This was an observational retrospective cohort study with historical comparison, comparing two cohorts (<32 weeks gestational age or very low birthweight) before and after the availability of donor human milk. The main explanatory variable was the PDHM cohort: pre-PDHM or post-PDHM. The primary dichotomous outcome variable was defined as whether the baby was being fed with breast milk only at the time of discharge home, compared with those fed with artificial formula alone or mixed feeding (artificial formula and breast milk). RESULTS: There were 1088 babies in the pre-PDHM cohort and 330 in the post-PDHM cohort (total n = 1418). Following the introduction of PDHM, 56% (185/330) were exclusively fed breast milk at the time of hospital discharge and 57% (620/1088) in the pre-PDHM cohort. The availability of PDHM is not a significant predictor of feeding outcome upon discharge (P = 0.45) when adjusted for maternal age, log-transformed post-natal age at discharge home and any congenital abnormality. CONCLUSIONS: The availability of donor human milk in our unit is not associated with a decrease in the number of very preterm infants receiving mother's own breast milk at time of discharge home. Other factors that positively impact the successful establishment of breastfeeding in preterm babies were older maternal age, the absence of any congenital abnormality and a shorter duration of hospital stay.