Coronary artery calcification on routine CT has prognostic and treatment implications for all ages.

AIMS: Guidelines have recommended reporting coronary artery calcification (CAC) if present on chest CT imaging regardless of indication. This study assessed CAC prevalence, prognosis and the potential clinical impact of its reporting. METHODS: We performed a single-centre retrospective analysis (January-December 2015) of 1400 chest CTs (200 consecutive within each age group: <40, 40-49, 50-59, 60-69, 70-79, 80-89, ≥90). CTs were re-reviewed for CAC presence and severity and excluded if prior coronary intervention. Comorbidities, statin prescription and clinical outcomes (myocardial infarction [MI], stroke, all-cause mortality) were recorded. The impact of reporting CAC was assessed against pre-existing statin prescriptions. RESULTS: 1343 patients were included (mean age 63±20 years, 56% female). Inter- and intra-observer variability for CAC presence at re-review was almost perfect (κ 0.89, p < 0.001; κ 0.90, p < 0.001) and for CAC grading was substantial and almost perfect (κ 0.68, p < 0.001; κ 0.91, p < 0.001). CAC was observed in 729/1343 (54%), more frequently in males (p < 0.001) and rising age (p < 0.001). A high proportion of patients with CAC in all age groups had no prior statin prescription (range: 42% [80-89] to 100% [<40]). The 'number needed to report' CAC presence to potentially impact management across all ages was 2. 689 (51%) patients died (median follow-up 74-months). CAC presence was associated with risk of MI, stroke and all-cause mortality (p < 0.001). After adjusting for confounders, severe calcification predicted risk of all-cause mortality (HR 1.8 [1.2-2.5], p = 0.002). CONCLUSION: Grading of CAC was reproducible, and although prevalence rose with age, prognostic and treatment implications were maintained in all ages.

Diagnostic accuracy of an automated artificial intelligence derived right ventricular to left ventricular diameter ratio tool on CT pulmonary angiography to predict pulmonary hypertension at right heart catheterisation.

AIM: To determine the diagnostic accuracy of an automated artificial intelligence derived right ventricle/left ventricle diameter ratio (RV/LV) computed tomography pulmonary angiography (CTPA) analysis tool to detect pulmonary hypertension (PH) in patients with suspected PH referred to a specialist centre. MATERIALS AND METHODS: The present study was a retrospective analysis of a prospectively maintained database of 202 consecutive patients with suspected PH, who underwent CTPA within 12 months of right heart catheterisation (RHC). Automated ventricular segmentation and RV/LV calculation (Imbio LLC, Minneapolis, MN, USA) was undertaken on the CTPA images. PH diagnosis was made using the RHC reference standard. RESULTS: The automated RV/LV correlated more strongly with RHC metrics than main pulmonary artery (MPA) diameter and MPA to ascending aorta diameter ratio (MPA/AA) measured manually (mean pulmonary arterial pressure [mPAP] r=0.535, R2 = 0.287 p<0.001; pulmonary vascular resistance [PVR] r=0.607, R2 = 0.369 p<0.001). In the derivation cohort (n=100), the area under the receiver-operating curve for automated RV/LV discriminating PH was 0.752 (95% confidence interval [CI] 0.677-0.827, p<0.001). Using an optimised Youden's Index of ≥1.12 classified from derivation, automated RV/LV ratio analysis was more sensitive for the detection of PH with higher positive predictive value (PPV) when compared with manual MPA and MPA/AA in the validation cohort (n=102). Automated RV/LV compromise (1.12) and specific (1.335) thresholds were strongly predictive of mortality (log-rank 7.401, p=0.007 and log-rank 16.075, p<0.001 respectively). CONCLUSION: In suspected PH, automated RV/LV diameter thresholds have high sensitivity for PH, outperform manual MPA and MPA/AA and can predict survival.

Computed tomography-derived fractional flow reserve (FFRCT) has no additional clinical impact over the anatomical Coronary Artery Disease - Reporting and Data System (CAD-RADS) in real-world elective healthcare of coronary artery disease.

AIM: To evaluate the impact of computed tomography-derived fractional flow reserve (FFRCT) compared to the anatomical Coronary Artery Disease - Reporting and Data System (CAD-RADS) in the elective assessment of coronary artery disease in real-world cardiology practise. MATERIALS AND METHODS: A retrospective review was undertaken of 1,239 coronary CT examinations from August 2018 to December 2019 with a minimum follow-up period of 1 year. Coronary disease was classified according to the CAD-RADS system. A non-occlusive ≥30% maximum diameter stenosis was considered eligible for FFRCT. Lesion-specific FFRCT and FFR were considered positive if ≤ 0.80. The patients were followed up using the hospital radiology information system and the electronic patient record. A positive outcome was defined by a subsequent invasive angiogram (ICA) showing disease requiring revascularisation or FFR ≤0.80 or a positive stress test or medical therapy for angina in CAD-RADS 4. RESULTS: Of the 1,145 analysable studies (mean follow up 618 ± 153 days) the incidence of a positive result was 7% with a 5.4% elective revascularisation rate. Two hundred and forty-five patients (CAD-RADS 2-4) had FFRCT. FFRCT reduced the accuracy of the CAD-RADS grade from 91% to 78.4% (p<0.001). In CAD-RADS 2, the accuracy is reduced from 99% to 90.7% (p=0.005), and in CAD-RADS 3 from 93.9% to 67.7% (p<0.001). In CAD-RADS 4, FFRCT increases accuracy from 69.4% to 75.5% (p=0.025), but 89.8% of FFRCT are positive and specificity is low (26.7%). CONCLUSION: In the present "real-world" practise, FFRCT does not improve standard radiological assessment of coronary disease graded by the CAD-RADS alone.

Systematic review and meta-analysis of the role of metronidazole in post-haemorrhoidectomy pain relief.

AIM: Conventional haemorrhoidectomy is still considered the reference standard for the management of severe or recurrent haemorrhoids. Pain is reported by patients to be the most common postoperative complication. Although the literature lacks a consensus on its effectiveness, metronidazole is often used to reduce postoperative pain. We have performed a meta-analysis of all randomized controlled trials (RCTs) that investigated the use of metronidazole for pain relief after haemorrhoidectomy. METHOD: A systematic review was undertaken in accordance with the PRISMA protocol using the MESH headings 'haemorrhoidectomy', 'hemorhoidectomy', 'hemorrhoidectomy', 'haemorrhoid', 'metronidazole', 'Flagyl® ' 'antibiotic' and 'pain'. The search returned 421 articles of which eight were RCTs suitable for inclusion in the review with a total population of 437 patients. The outcomes of interest were postoperative pain intensity on days 1, 2 and 7 and on first defaecation as measured using a visual analogue scale. RESULTS: The meta-analysis demonstrated a significant reduction in postoperative pain for patients treated with metronidazole with a reduced mean difference for the metronidazole group on day 1 of -1.42 (95% CI: -2.14 to -0.69, P = 0.0001), on day 2 of -1.43 (95% CI: -2.45 to -0.40, P = 0.006) and on day 7 of -2.40 (95% CI: -3.10 to -1.71, P < 0.00001). Pain on first defaecation was likewise reduced with a mean difference of -1.38 (95% CI: -2.15 to -0.60, P = 0.0005). Limitations of this study include variation in the grade of haemorrhoids treated and variability in the quality of included studies. CONCLUSION: Metronidazole is a cheap, safe and effective intervention for reducing postoperative pain following conventional haemorrhoidectomy.

Responsive Contingency Planning: a novel system for anticipated difficulty in airway management in dental abscess.

BACKGROUND: This study is of a novel system for management of anticipated difficult airway (Responsive Contingency Planning). It is based on the notion that almost all problems in airway management have already been experienced, so they can be anticipated and prepared for using 'worst case' planning. METHODS: Anaesthetic colleagues were introduced to the new system. Thirty-two patients with dental abscess were recruited for anaesthetic airway management based around the new scheme. Data collection involved a preoperative assessment of problems specific to dental abscess, fascia-spaces involved, details of the contingency planning process, laryngoscopy grade, and comments regarding the efficacy of the new system. RESULTS: No problems were encountered that had not been anticipated during planning and colleagues' comments about using the system were generally favourable. Examples are highlighted to suggest how the planning may have avoided certain complications (e.g. abscess rupture) and helped in dealing with others when they occurred. If trismus (2 cm) after induction of anaesthesia. In contrast, difficult laryngoscopy (grade 3 or 4) occurred in 6/15 cases of floor of mouth infection. CONCLUSIONS: The system fulfilled expectations for its use at this stage of development. It can be easily updated for refinements, alternative techniques, and tailoring to any difficult airway scenario. Computerization should make it easier to use and flag-up inconsistencies. Floor of mouth infections in the presence of trismus are easily underestimated and require careful assessment.

Anaesthesia for head and neck surgery: United Kingdom National Multidisciplinary Guidelines.

This is the official guideline endorsed by the specialty associations involved in the care of head and neck cancer patients in the UK. The anaesthetic considerations for head and neck cancer surgery are especially challenging given the high burden of concurrent comorbidity in this patient group and the need to share the airway with the surgical team. This paper provides recommendations on the anaesthetic considerations during surgery for head and neck cancer. Recommendations • All theatre staff should participate in the World Health Organization checklist process. (R) • Post-operative airway management should be guided by local protocols. (R) • Patients admitted to post-operative care units with tracheal tubes in place should be monitored with continuous capnography. Removal for tracheal tubes is the responsibility of the anaesthetist. (R) • Anaesthetists should formally hand over care to an appropriately trained practitioner in the post-operative or intensive care unit. (G) • Intensive care unit staff looking after post-operative tracheostomies must be clear about which patients are not suitable for bag-mask ventilation and/or oral intubation in the event of emergencies. (R).

Monoclonal antibodies against vascular endothelial antigens expressed in normal human brain.

A panel of monoclonal antibodies reactive with human-brain vessels was raised by immunizing BALB/c mice with homogenate of whole human brain, obtained from temporal lobectomies. Hybridoma supernates were screened by immunohistochemical methods on frozen sections of human brain, liver and spleen and 16 clones were isolated. The pattern of immunoreactivity varied with respect to the type of brain blood vessels predominantly labelled and to tissue specificity. Some antibodies cross-reacted with cow or squirrel monkey forebrain microvessels with an intensity equal to that shown by human brain. The immunoreactivity patterns reflected antigenic heterogeneity among different subsets of vascular endothelial cells in human brain.

A biomechanical model of the upper airways for simulating laryngoscopy.

This paper describes a three-dimensional finite element model of the human upper airways during rigid laryngoscopy. In this procedure, an anaesthetist uses a rigid blade to displace and compress the tongue of the patient, and then inserts a tube into the larynx to allow controlled ventilation of the lungs during an operation. A realistic model of the main biomechanical aspects involved would help anaesthetists in training and in predicting difficult cases in advance. For this purpose, the finite element method was used to model structures such as the tongue, ligaments, larynx, vocal cords, bony landmarks, laryngoscope blade, and their inter-relationships, based on data extracted from X-ray, MRI, and photographic records. The model has been used to investigate how the tongue tissue behaves in response to the insertion of the laryngoscope blade, when it is subjected to a variety of loading conditions. In particular, the mechanical behaviour of the soft tissue of the tongue was simulated, from simple linear elastic material to complex non-linear viscoelastic material. The results show that, within a specific set of tongue material parameters, the simulated outcome can be successfully related to the view of the vocal cords achieved during real laryngoscopies on normal subjects, and on artificially induced difficult laryngoscopy, created by extending the upper incisors teeth experimentally.

Acute airway obstruction due to ruptured aneurysmal arterio-venous fistula: common carotid artery to internal jugular vein.

Fistulae between major vessels in the head and neck are uncommon. In both civilian and wartime reports, the total number of traumatic arterio-venous fistulae in head and neck region account for less than four per cent of all arterial injuries. Fourteen cases of congenital communication between the external carotid artery and external or internal jugular vein have been reported. We report and discuss the management of a case of ruptured carotico-jugular fistula secondary to infection which presented as acute upper airway obstruction. This appears to be the first description of such a case in the literature.

Airway intervention in adult supraglottitis.

BACKGROUND: The timing of aggressive airway intervention in adult epiglottitis is controversial. AIMS: To correlate Friedman's staging of epiglottitis on admission with the airway interventions undertaken. METHODS: A retrospective study of 23 adult patients, mean age 51 years (range 29-81 years), who had been admitted with acute supraglottitis between March 1988 and December 2000 was undertaken. RESULTS: Three patients (13%) had airway interventions; two with tracheostomy and one with tracheal intubation. All were Friedman stage III and had rapid symptom progression during the 24 hours prior to admission. Three other stage III patients with symptom progression longer than 24 hours and all the remaining patients (stage II or less) were managed with observation and intravenous therapy. CONCLUSIONS: Friedman originally advocated airway intervention in any patient stage II or worse, but this intubation threshold should probably be lowered to those patients with rapid-onset stage Ill (moderate respiratory distress, stridor, respiratory rate > 30 per minute, pCO2 > 45mmHg) disease.

The religious and spiritual needs of mental health clients.

This research study demonstrates the necessity for mental health nurses and allied clinical staff to be conscious that their clients may have spiritual and religious needs. A comprehensive assessment of these religious and spiritual needs should be standard practice, and multidisciplinary liaison and utilisation of chaplaincy resources are essential.

A randomised, crossover study of the Dorges, McCoy and Macintosh laryngoscope blades in a simulated difficult intubation scenario.

The use of alternative adult laryngoscope blades in an unexpected difficult intubation was evaluated with a human patient simulator manikin. Twenty anaesthetists of varying experience attempted to intubate the trachea of a high fidelity simulator in both its normal and difficult intubation settings using Macintosh, Dorges and McCoy laryngoscopes in a randomised order. The time taken to intubate, Cormack and Lehane scores, percentage of glottic opening visible, failure rate, number of attempts and subjective ease of use were recorded. The Dorges and McCoy blades did not perform any better than the standard Macintosh blade in either the easy or difficult tracheal intubation settings. Guidelines recommending the use of an alternative blade in an unexpected difficult intubation scenario have limited supporting evidence. This study does not support this recommendation.

Acoustic parameters of snoring sound to compare natural snores with snores during 'steady-state' propofol sedation.

OBJECTIVES: To investigate the acoustic similarity between natural and sedation-induced snores. DESIGN: Prospective observational study. SETTING: University Hospital Aintree, Liverpool, UK. PARTICIPANTS: Twenty-one patients, who had already had overnight snore recordings, completed a pre-operative sleep nasendoscopic examination. Endoscopic examination of the upper aero-digestive tract was performed at sequentially increasing, steady-state sedation levels, using intravenous propofol administered according to a weight/time-based algorithm to predict blood and effect site (tissue) concentrations. At each sedation level at which snoring occurred, snoring sound was recorded. From these samples, snore files, comprising the inspiratory sound of each snore were created. Similarly, from natural snores recorded pre-operatively, snore files, comprising the inspiratory sounds of the first 100 snores with the patient sleeping in a supine position, were also created. MAIN OUTCOME MEASURES: Snore duration (s), loudness (dBA), periodicity (%) and energy ratios for the frequency sub-bands 0-200, 0-250 and 0-400 Hz. RESULTS: Snore loudness increased significantly (P < 0.0001), whilst energy ratios for frequency bands 0-200, 0-250 and 0-400 Hz all decreased significantly as sedation level increased (P < 0.001). A significant difference between natural snoring and snoring induced at the lowest sedation level was shown (P < 0.0001). Endoscopic examination was not tolerated at this sedation level. CONCLUSIONS: The acoustic characteristics of sedation-induced and natural snores are sufficiently different to recommend the need for further research to determine whether the technique of sleep nasendoscopy is, in fact, a valid predictor of outcome of snoring surgery.

Survival after massive bleeding into the airway in a patient at risk from "can't intubate, can't ventilate".

A patient survived massive bleeding into the airway due to blowout of the right internal jugular vein associated with a failed free-flap graft for pharyngeal malignancy. A recently decannulated "covering tracheostomy" could not be easily re-established. Direct laryngoscopy and mask ventilation were inappropriate because the pharyngeal mucosal wound opened spontaneously and progressively and bleeding was dramatic. Positive pressure ventilation via a facemask risked widespread surgical emphysema and further wound disruption and because bleeding was from the internal jugular vein, there would also have been a risk of air embolism. The clinical situation evolved rapidly so time management and consideration of hierarchy of mortality risks was critical. It was eventually possible to re-establish the previous tracheostomy site as a result of close co-operation between the surgical and anaesthetic teams. In difficult intubation where the problems are anticipated, the notion of responsive contingency planning is suggested to be of more general relevance than the current standard of considering alternative fallback options. The limitations of conventional capnography in this situation are also noteworthy.

Analysis of mathematical model for osseous factors in difficult intubation.

A two-dimensional model of the factors relevant to difficult laryngoscopy was analysed mathematically to determine clinical implications and limitations. The model describes the space into which the "inevitable residual volume" of the tongue (that part remaining anterior to the blade at laryngoscopy) can be displaced to permit a view of the larynx. Four points are used: the tip of the upper incisors; a point on the anterior airway just above the larynx; the mid-point between the mandibular condyles and the internal mid-point of the symphysis. The number, F, was defined by a formula developed from their spacial relationships. Decreasing F values imply an increasing likelihood of difficult laryngoscopy. The analysis investigated the effects of: translation of individual points; plotting individual point positions for specified F-values; translating adjacent pairs of points; treating any three points as a triangle which rotates about each of its apices; and lastly, translating three points independently. During manipulations the model behaved well mathematically. Single point analysis implied that jaw recession and a non-protruding mandible were comparable in effect. Closing the mouth around the laryngoscope blade maximised F-values. Prominence of the maxilla required greater forward displacement than backward movement of the symphysis for equivalent F-value change. One particular triangular rotation suggested an entirely novel mechanism for difficulty (the "hi-slung mandible") where the condyles are positioned more rostral than normal. An otherwise normal jaw with this configuration recedes markedly on opening. Further studies are required to validate the model. Accurate quantification of individual factors in difficult laryngoscopy may then be feasible.

Mannitol, osmolality and steroids during renal transplantation. Real and theoretical influences on plasma potassium.

Mannitol did not have an exaggerated effect on plasma potassium when administered to twelve patients undergoing renal transplantation. Unexpected rises in plasma osmolality, greater than those recorded after mannitol, were observed in two of the patients. In these two patients the osmolality changes were due to sudden hyperglycaemia and followed methylprednisolone therapy (given for immunosuppression). It is suggested that under certain circumstances, such changes in osmolality may lead to a rise in plasma potassium comparable to the effect of mannitol. One of the two patients with the rise in glucose and osmolality did have a rise in plasma potassium.

Renal transplantation in diabetes mellitus.

Renal failure is common in patients with diabetes mellitus, and renal transplantation has been used in its treatment. There are indications that the operation may be hazardous in these circumstances, and a report is presented in which careful biochemical monitoring of a diabetic patient undergoing transplantation revealed two episodes of hyperkalaemia which might go some way to explain the hazards of this operation. The relevance of the concept of glucose-induced hyperkalaemia is discussed and it is suggested that intravenous infusion of insulin during and after operation might have decreased the rises in serum potassium. The report emphasises the need for careful biochemical monitoring of diabetics undergoing renal transplantation.