The association between borderline pre‐operative anaemia in women and outcomes after cardiac surgery: a cohort study

Anaemia is common before cardiac surgery and is associated with increased morbidity and mortality. The World Health Organization (WHO) definition of anaemia is lower for women than for men by 10 g.l^?1, potentially putting women at a disadvantage compared with men with regard to pre‐operative optimisation. Our hypothesis was that women with borderline anaemia (defined by us as haemoglobin concentration 120–129 g.l^?1) would have a higher rate of red cell transfusion, morbidity and mortality than non‐anaemic women (haemoglobin ≥ 130 g.l^?1). This retrospective observational study included all adult patients admitted for elective cardiac surgery from January 2013 to April 2016. During the study period, 1388 women underwent cardiac surgery. Pre‐operatively, 333 (24%) had a haemoglobin level < 120 g.l^?1; 408 (29%) 120–129 g.l^?1; and 647 (47%) ≥ 130 g.l^?1. Compared with non‐anaemic women, women with borderline anaemia were more likely to be transfused (68.6% vs. 44.5%; RR 1.5, 95%CI 1.4–1.7; p < 0.0001) and were transfused with more units of red cells, mean (SD) 1.8 (2.8) vs. 1.3 (3.0); p < 0.0001. Hospital length of stay was significantly longer in the borderline anaemia group compared with non‐anaemic women, median (IQR [range]) 8 (6–12 [3–45]) vs. 7 (6–11 [4–60]); p = 0.0159. Short‐ and long‐term postoperative survival was comparable in both groups. Borderline anaemia is associated with increased red cell transfusion and prolonged hospital stay. Future research should address whether correction of borderline anaemia results in improved outcomes.     

Postoperative outcomes following cardiac surgery in non‐anaemic iron‐replete and iron‐deficient patients – an exploratory study

Iron deficiency anaemia is strongly associated with poor outcomes after cardiac surgery. However, pre‐operative non‐anaemic iron deficiency (a probable anaemia precursor) has not been comprehensively examined in patients undergoing cardiac surgery, despite biological plausibility and evidence from other patient populations of negative effect on outcome. This exploratory retrospective cohort study aimed to compare an iron‐deficient group of patients undergoing cardiac surgery with an iron‐replete group. Consecutive non‐anaemic patients undergoing elective coronary artery bypass grafting or single valve replacement in our institution between January 2013 and December 2015 were considered for inclusion. Data from a total of 277 patients were analysed, and were categorised by iron status and blood haemoglobin concentration into iron‐deficient (n = 109) and iron‐replete (n = 168) groups. Compared with the iron‐replete group, patients in the iron‐deficient group were more likely to be female (43% vs. 12%, iron‐replete, respectively); older, mean (SD) age 64.4 (9.7) vs. 63.2 (10.3) years; and to have a higher pre‐operative EuroSCORE (median IQR [range]) 3 (2–5 [0–10]) vs. 3 (2–4 [0–9]), with a lower preoperative haemoglobin of 141.6 (11.6) vs. 148.3 (11.7) g.l^?1. Univariate analysis suggested that iron‐deficient patients had a longer hospital length of stay (7 (6–9 [2–40]) vs. 7 (5–8 [4–23]) days; p = 0.013) and fewer days alive and out of hospital at postoperative day 90 (83 (80–84 [0–87]) vs. 83 (81–85 [34–86]), p = 0.009). There was no evidence of an association between iron deficiency and either lower nadir haemoglobin or higher requirement for blood products during inpatient stay. After adjusting the model for pre‐operative age, sex, renal function, EuroSCORE and haemoglobin, the mean increase in hospital length of stay in the iron‐deficient group relative to the iron‐replete group was 0.86 days (bootstrapped 95%CI ?0.37 to 2.22, p = 0.098). This exploratory study suggests there is weak evidence of an association between non‐anaemic iron deficiency and outcome after cardiac surgery after controlling for potentially confounding variables.     

The effect of intra-operative hypotension on acute kidney injury,postoperative mortality and length of stay following emergency hip fracture surgery

The association between intra-operative hypotension and postoperative acute kidney injury, mortality and length of stay has not been comprehensively evaluated in a large single-centre hip fracture population. We analysed electronic anaesthesia records of 1063 patients undergoing unilateral hip fracture surgery, collected from 2015 to 2018. Acute kidney injury, 3-, 30- and 365-day mortality and length of stay were evaluated to assess the relationship between intra-operative hypotension absolute values (≤ 55, 60, 65, 70 and 75 mmHg) and duration of hypotension. The rate of acute kidney injury was 23.7%, mortality at 3-, 30- and 365 days was 3.7%, 8.0% and 25.3%, respectively, and median (IQR [range]) length of stay 8 (6–12 [0–99]) days. Median (IQR [range]) time ≤ MAP 55, 60, 65, 70 and 75 mmHg was 0 (0–0.5[0–72.1]); 0 (0–4.4 [0–104.9]); 2.2 (0–8.7 [0–144.2]); 6.6 (2.2–19.7 [0–198.8]); 17.5 (6.6–37.1 [0–216.3]) minutes, and percentage of surgery time below these thresholds was 1%, 2.5%, 7.9%, 12% and 21% respectively. There were some univariate associations between hypotension and mortality; however, these were no longer evident in multivariable analysis. Multivariable analysis found no association between hypotension and acute kidney injury. Acute kidney injury was associated with male sex, antihypertensive medications and cardiac/renal comorbidities. Three-day mortality was associated with delay to surgery ? 48 hours, whilst 30-day and 365-day mortality was associated with delay to surgery ≥ 48 hours, impaired cognition and cardiac/renal comorbidities. While the rate of acute kidney injury was similar to other studies, use of vasopressors and fluids to reduce the time spent at hypotensive levels failed to reduce this complication. Intra-operative hypotension at the levels observed in this cohort may not be an important determinant of acute kidney injury, postoperative mortality and length of stay.     

Effect of 6% hydroxyethyl starch 130/0.4 on kidney and haemostatic function in cardiac surgical patients: a randomised controlled trial

Whether third-generation hydroxyethyl starch solutions provoke kidney injury or haemostatic abnormalities in patients having cardiac surgery remains unclear. We tested the hypotheses that intra-operative administration of a third-generation starch does not worsen postoperative kidney function or haemostasis in cardiac surgical patients compared with human albumin 5%. This triple-blind, non-inferiority, clinical trial randomly allocated patients aged 40–85 who underwent elective aortic valve replacement, with or without coronary artery bypass grafting, to plasma volume replacement with 6% starch 130/0.4 vs. 5% human albumin. Our primary outcome was postoperative urinary neutrophil gelatinase-associated lipocalin concentrations, a sensitive and early marker of postoperative kidney injury. Secondarily, we evaluated urinary interleukin-18; acute kidney injury using creatinine RIFLE criteria, coagulation measures, platelet count and function. Non-inferiority (delta 15%) was assessed with correction for multiple comparisons. We enrolled 141 patients (69 starch, 72 albumin) as planned. Results of the primary analysis demonstrated that postoperative urine neutrophil gelatinase-associated lipocalin (median (IQR [range])) was slightly lower with hydroxyethyl starch (5 (1–68 [0–996]) ng.ml⁻¹) vs. albumin (5 (2–74 [0–1604]) ng.ml⁻¹), although not non-inferior [ratio of geometric means (95%CI) 0.91 (0.57, 1.44); p = 0.15] due to higher than expected variability. Urine interleukin-18 concentrations were reduced, but interleukin-18 and kidney injury were again not non-inferior. Of 11 individual coagulation measures, platelet count and function, nine were non-inferior to albumin. Two remaining measures, thromboelastographic R value and arachidonic acid-induced platelet aggregation, were clinically similar but with wide confidence intervals. Starch administration during cardiac surgery produced similar observed effects on postoperative kidney function, coagulation, platelet count and platelet function compared with albumin, though greater than expected variability and wide confidence intervals precluded the conclusion of non-inferiority. Long-term mortality and kidney function appeared similar between starch and albumin.     

The association of hypotension during non‐cardiac surgery,before and after skin incision,with postoperative acute kidney injury: a retrospective cohort analysis

Intra‐operative hypotension is associated with acute postoperative kidney injury. It is unclear how much hypotension occurs before skin incision compared with after, or whether hypotension in these two periods is similarly associated with postoperative kidney injury. We analysed the association of mean arterial pressure < 65 mmHg with postoperative kidney injury in 42,825 patients who were anaesthetised for elective non‐cardiac surgery. Intra‐operative hypotension occurred in 30,423 (71%) patients: 22,569 (53%) patients before skin incision; and 24,102 (56%) patients after incision. Anaesthetised patients who were hypotensive had mean arterial pressures < 65 mmHg for a median (IQR [range]) of 5.5 (0.0–14.7 [0.0–60.0]) min.h^?1 before skin incision, compared with 1.7 [0.3–5.1 [0.0–57.5]) min.h^?1 after incision: a median (IQR [range]) of 36% (0%–84% [0%–100%]) of hypotensive readings were before incision. We diagnosed postoperative kidney injury in 2328 (5%) patients. The odds ratio (95%CI) for acute kidney injury was 1.05 (1.02–1.07) for each doubling of the duration of hypotension, p < 0.001. Postoperative kidney injury was associated with the product of hypotension duration and severity, that is, area under the curve, before skin incision and after, odds ratio (95%CI): 1.02 (1.01–1.04), p = 0.004; and 1.02 (1.00–1.04), p = 0.016, respectively. A substantial fraction of all hypotension happened before surgical incision and was thus completely due to anaesthetic management. We recommend that anaesthetists should avoid mean arterial pressure < 65 mmHg during surgery, especially after induction, assuming that its association with postoperative kidney injury is, at least in part, causal.     

A double-blind randomised feasibility trial of angiotensin-2 in cardiac surgery*

Acute kidney injury is common after cardiac surgery. Vasoplegic hypotension may contribute to kidney injury, and different vasopressors may have variable effects on kidney function. We conducted a double-blind, randomised feasibility trial comparing peri-operative angiotensin-2 with noradrenaline. We randomly allocated 60 patients at two centres to a blinded equipotent angiotensin-2 or noradrenaline infusion intra-operatively and for up to 48 h postoperatively, titrated to mean arterial pressure of 70–80 mmHg. Primary feasibility outcomes included consent rate, protocol adherence, infusion duration, mean arterial pressure maintenance in the target range and major adverse outcomes. Secondary outcomes included kidney injury rate. The consent rate was 47%. Protocol adherence was 100% in the angiotensin-2 group and 94% in the noradrenaline group. Study drug duration was median (IQR [range]) 217 (160–270 [30–315]) vs. 185 (135–301 [0–480]) min (p = 0.78) min intra-operatively, and 5 (0–16 [0–48]) vs. 14.5 (4.8–29 [0–48]) hours (p = 0.075) postoperatively for angiotensin-2 and noradrenaline, respectively. The mean arterial pressure target was achieved postoperatively in 25 of 28 (89%) of the angiotensin-2 group and 27 of 32 (84%) of the noradrenaline group. One participant had a stroke, one required extracorporeal support and three required renal replacement therapy, all in the noradrenaline group (p = 0.99, p = 0.99 and p = 0.1). Acute kidney injury occurred in 7 of 28 in the angiotensin-2 group vs. 12 of 32 patients in the noradrenaline group (p = 0.31). This pilot study suggests that a trial comparing angiotensin-2 with noradrenaline is feasible. Its findings justify further investigations of angiotensin-2 in cardiac surgery.     

Improved outcomes of renal injury following burn trauma

BackgroundAcute kidney injury (AKI) is common in major burn injuries and associated with increased mortality. With advances in surgical and critical care it is unclear if mortality in this population remains this high. This study aims to describe incidence and outcomes of patients admitted to intensive care (ICU) with a burn injury who develop AKI. We additionally sought to determine risk factors for developing AKI.MethodsA historical cohort study of patients admitted to ICU from 2010 to 2016 with major burn injury was conducted. Demographic, laboratory, and clinical information was collected. AKI was defined by Acute Kidney Injury Network (AKIN) classification. Multivariable logistic regression was used to model association between baseline risk factors and risk of AKI.ResultsOf the 151 patients included, 64 people developed AKI (42%) defined by stages 1–3 of AKIN criteria. The median TBSA was 20% (IQR 9–41). Renal replacement therapy was required in 18/64 (28%) who developed AKI. Multivariable logistic regression demonstrated association between AKI and the following variables: APACHE II score (OR 1.2, 95%CI 1.1–1.3, P = 0.001), age (OR 1.8 per 10-year increase, 95%CI: 1.2–2.5, P = 0.002) and log(TBSA). Fractional polynomial regression analysis demonstrates that the best functional form of TBSA was in the natural logarithm (OR 2.7, 95%CI: 1.5–4.7, p = 0.001). Compared to those without AKI, patients with AKI had longer duration of mechanical ventilation, (median 11 [IQR 6–19] vs. 4 [IQR 2–9] days), ICU stay (15 [IQR 9–22] vs. 6 [IQR 3–10] days), and increased mortality (14 of 64(22%) vs. 4 of 87(5%).ConclusionsAKI is common in patients with a major burn injury. However, mortality is lower than described in the literature, particularly for those who required renal replacement therapy.     

Observational study of pre-operative intravenous iron given to anaemic patients before elective cardiac surgery

Cardiac surgical patients with anaemia experience increased morbidity and mortality. Iron deficiency is the most common cause of pre-operative anaemia in this group. We designed and implemented the Cardiff Pathway, a pre-assessment and treatment pathway to identify cardiac surgical patients with anaemia and iron deficiency. Patients identified with anaemia and/or iron deficiency (Hb < 130 g.l^-1 and ferritin < 100 μg.l^-1) were offered intravenous iron infusion 20 mg.kg^-1 pre-operatively. Treatment success was defined as Hb ≥ 130g.l^-1 on the day of surgery. We analysed data from 447 patients: 300 (67%) were not anaemic; 75 (17%) were anaemic and treated with intravenous iron; and 72 (16%) were anaemic and not treated. Haemoglobin concentration increased in successfully treated anaemic patients by a mean (95%CI) of 17 (13–21) g.l^-1 and they received a median (IQR [range]) of 0 (0–2 [0–15]) units of blood peri-operatively. Transfusion was avoided in 54% of the successfully treated anaemic patients, which was significantly more than the unsuccessfully treated anaemic (22%, p = 0.005) and untreated anaemic (28%, p = 0.018) patients and similar to non-anaemic patients who received a median (IQR [range] of 0 (0–1 [0–16])) units of blood and, 63% avoided transfusion). Mean (95%CI) Hb fell between pre-assessment and surgery in the untreated anaemic (-2 (0 to -4) g.l^-1) and non-anaemic groups (-2 (-1 to -3) g.l^-1). Twenty-one (7%) of the non-anaemic group became newly anaemic waiting for surgery. The Cardiff Pathway reliably identified patients with anaemia and iron deficiency. Anaemic patients who had their Hb restored to normal after treatment required less blood peri-operatively and over half of them required no transfusion at all.     

Impact of a peri‐operative quality improvement programme on postoperative pulmonary complications

Postoperative pulmonary complications are common, with a reported incidence of 2–40%, and are associated with adverse outcomes that include death, longer hospital stay and reduced long‐term survival. Enhanced recovery is now a standard of care for patients undergoing elective major surgery. Despite the high prevalence of pulmonary complications in this population, few elements of enhanced recovery specifically address reducing these complications. In 2013, a prevalence audit confirmed a postoperative pulmonary complication rate of 16/83 (19.3%) in patients undergoing elective major surgery who were admitted to critical care postoperatively. A quality improvement team developed and implemented ERAS+, an innovative model of peri‐operative care combining elements of enhanced recovery with specific measures aimed at reducing pulmonary complications. ERAS+ was introduced in June 2014, with full implementation in September 2014. Patients were screened during full ERAS+ implementation and again one year following implementation. Following ERAS+ implementation, postoperative pulmonary complications reduced to 24/228 (10.5%). Sustained improvement was evident one year after implementation, with a pulmonary complication rate of 16/183 (8.7%). Median (IQR [range]) length of hospital stay one year after implementation of ERAS+ also improved from 12 (9–15 [4‐101]) to 9 (5.5–10.5 [3‐81]) days. The ERAS+ pathway is applicable to patients undergoing elective major surgery and appears effective in reducing postoperative pulmonary complications.     

Survival and length of stay following blood transfusion in octogenarians following cardiac surgery

Our aim was to assess if peri‐operative blood transfusion is an independent risk factor for mortality and morbidity in the elderly. We report the results of a cohort study of all patients aged 80 or more on the day of their emergency or elective cardiac surgery (n = 874), using routinely collected data from January 2003 to November 2007. The primary outcome was all‐cause mortality in hospital. The secondary outcomes were duration of stay in the intensive care unit (ICU) and overall hospital stay. Confounding variables were used to build up a risk model using a multivariable logistic regression analysis, and blood transfusion was added to assess whether it had additional predictive value for hospital mortality. Patients were divided into three groups: (i) transfusion of 0–2 units of red blood cells; (ii) transfusion of > 2 units of red blood cells and (iii) transfusion of red blood cells plus other clotting products. The strongest independent predictors of hospital death were logistic EuroSCORE and body mass index. After inclusion of these two variables, the odds ratio for transfusion remained significant. Relative to 0–2 units, the odds ratio for > 2 units was 6.80 (95% CI 2.46–18.8), and for other additional blood products was 14.4 (95% CI 5.34–37.3), with a p value of < 0.001. Duration of stay in the ICU was significantly associated with the amount of blood products administered (median (IQR [range]) ICU stay 1 (1‐2 [0‐15]) day if transfused 0–2 units of red blood cells, 2 (1‐6 [0‐128]) days if transfused > 2 units of red blood cells and 3 (1‐76 [0‐114]) days if other clotting products were used; p value < 0.001). Hospital stay was also associated with the amount of red cells used (p < 0.001).     

The association between tranexamic acid and convulsive seizures after cardiac surgery: a multivariate analysis in 11 529 patients

Because of a lack of contemporary data regarding seizures after cardiac surgery, we undertook a retrospective analysis of prospectively collected data from 11 529 patients in whom cardiopulmonary bypass was used from January 2004 to December 2010. A convulsive seizure was defined as a transient episode of disturbed brain function characterised by abnormal involuntary motor movements. Multivariate regression analysis was performed to identify independent predictors of postoperative seizures. A total of 100 (0.9%) patients developed postoperative convulsive seizures. Generalised and focal seizures were identified in 68 and 32 patients, respectively. The median (IQR [range]) time after surgery when the seizure occurred was 7 (6–12 [1–216]) h and 8 (6–11 [4–18]) h, respectively. Epileptiform findings on electroencephalography were seen in 19 patients. Independent predictors of postoperative seizures included age, female sex, redo cardiac surgery, calcification of ascending aorta, congestive heart failure, deep hypothermic circulatory arrest, duration of aortic cross‐clamp and tranexamic acid. When tested in a multivariate regression analysis, tranexamic acid was a strong independent predictor of seizures (OR 14.3, 95% CI 5.5–36.7; p < 0.001). Patients with convulsive seizures had 2.5 times higher in‐hospital mortality rates and twice the length of hospital stay compared with patients without convulsive seizures. Mean (IQR [range]) length of stay in the intensive care unit was 115 (49–228 [32–481]) h in patients with convulsive seizures compared with 26 (22–69 [14–1080]) h in patients without seizures (p < 0.001). Convulsive seizures are a serious postoperative complication after cardiac surgery. As tranexamic acid is the only modifiable factor, its administration, particularly in doses exceeding 80 mg.kg^?1, should be weighed against the risk of postoperative seizures.     

Haemodynamic changes to a midazolam–fentanyl–rocuronium protocol for pre‐hospital anaesthesia following return of spontaneous circulation after cardiac arrest

Following the return of spontaneous circulation after out‐of‐hospital cardiac arrest, neurological dysfunction, airway or ventilatory compromise can impede transport to early percutaneous coronary intervention, necessitating pre‐hospital or emergency department anaesthesia to facilitate this procedure. There are no published reports of the ideal induction agents in these patients. We sought to describe haemodynamic changes associated with induction of anaesthesia using a midazolam (0.1 mg.kg^?1), fentanyl (2 μg.kg^?1) and rocuronium (1 mg.kg^?1) regimen developed using expert opinion, and adherence to the protocol by our pre‐hospital teams. We performed a retrospective review of haemodynamic data recorded during induction of anaesthesia in patients following return of spontaneous circulation, over a 30‐month period. We analysed the changes in systolic blood pressure and heart rate using a repeated‐measures design, as well as the rate of new hypotension or hypertension. Sixty‐four patients had four consecutive measurements for analysis (one pre‐induction and three post‐induction). Systolic blood pressure at all three post‐induction measurements was significantly lower than the pre‐induction value. Heart rate did not differ between any time‐points. New episodes of hypotension (systolic pressure < 90 mmHg) occurred in four (6%) patients at the first measurement post‐induction (95%CI 2–15%) and 10 (16%) at the third measurement (95%CI 8–27%). Three patients (5%; 95%CI 1–13%) had a hypertensive response. The median (IQR [range]) dose of midazolam given at induction was 0.04 (0.03‐0.05 [0.01 to 0.10]) mg.kg^?1. Adherence to recommended fentanyl and rocuronium doses was high. Overall, systolic blood pressure was reduced following induction of anaesthesia, and systolic pressures < 90 mmHg occurred more often at measurements made later (up to 9 min) after induction. Changes in heart rate, and new hypertension were uncommon.     

Delirium after transcatheter aortic valve implantation via the femoral or apical route

We thought that delirium might be less frequent after transcatheter aortic valve implantation via the femoral artery compared with via the cardiac apex. We reviewed 210 patients who underwent transcatheter aortic valve implantation between January 2009 and October 2014. The proportion (95% CI) of patients who suffered delirium in the 3 days after valve implantation were: 10 (3–16%) in 105 patients who had transfemoral implantation; and 35 (25–45%) in 105 patients who had transapical implantation, p = 0.0001. The variables that independently associated with postoperative delirium were age, male sex and the transapical approach. The median (IQR [range]) hospital stay was 7 (5–13 [2–41]) days and 10 (7–15 [2–64]) days, respectively, p = 0.004. Future trials should focus on different peri‐operative management strategies to reduce delirium rates after transcatheter aortic valve implantation, particularly in older men having implantations via the cardiac apex.     

Comparison of peripheral nerve blockade characteristics between non‐diabetic patients and patients suffering from diabetic neuropathy: a prospective cohort study

Animal data have demonstrated increased block duration after local anaesthetic injections in diabetic rat models. Whether the same is true in humans is currently undefined. We, therefore, undertook this prospective cohort study to test the hypothesis that type‐2 diabetic patients suffering from diabetic peripheral neuropathy would have increased block duration after ultrasound‐guided popliteal sciatic nerve block when compared with patients without neuropathy. Thirty‐three type‐2 diabetic patients with neuropathy and 23 non‐diabetic control patients, scheduled for fore‐foot surgery, were included prospectively. All patients received an ultrasound‐guided popliteal sciatic nerve block with a 30 ml 1:1 mixture of lidocaine 1% and bupivacaine 0.5%. The primary outcome was time to first opioid request after block procedure. Secondary outcomes included the time to onset of sensory blockade, and pain score at rest on postoperative day 1 (numeric rating scale 0–10). These outcomes were analysed using an accelerated failure time regression model. Patients in the diabetic peripheral neuropathy group had significantly prolonged median (IQR [range]) time to first opioid request (diabetic peripheral neuropathy group 1440 (IQR 1140–1440 [180–1440]) min vs. control group 710 (IQR 420–1200 [150–1440] min, p = 0.0004). Diabetic peripheral neuropathy patients had a time ratio of 1.57 (95%CI 1.10–2.23, p < 0.01), experienced a 59% shorter time to onset of sensory blockade (median time ratio 0.41 (95%CI 0.28–0.59), p < 0.0001) and had lower median (IQR [range]) pain scores at rest on postoperative day 1 (diabetic peripheral neuropathy group 0 (IQR 0–1 [0–5]) vs. control group 3 (IQR 0–5 [0–9]), p = 0.001). In conclusion, after an ultrasound‐guided popliteal sciatic nerve block, patients with diabetic peripheral neuropathy demonstrated reduced time to onset of sensory blockade, with increased time to first opioid request when compared with patients without neuropathy.     

Effect of iron deficiency without anaemia on days alive and out of hospital in patients undergoing valvular heart surgery

Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml^-1 or < 300 ng.ml^-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l^-1, 143 (133–150 [120–179]) g.l^-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.     

A feasibility study of awake videolaryngoscope‐assisted intubation in patients with periglottic tumour using the channelled King Vision® videolaryngoscope

Airway management in patients with periglottic tumour is a high‐risk procedure with potentially serious consequences. There is no consensus on how best to secure the airway in this group of patients. We conducted a feasibility study of awake tracheal intubation using a King Vision^® videolaryngoscope with a channelled blade in a cohort of 25 patients, with a periglottic tumour requiring diagnostic or radical surgery. We used 10% and 4% lidocaine to topicalise the airway and midazolam and remifentanil for sedation. We recorded the success rate, number of attempts, time to obtain glottic view, time to intubation and complications. Twenty‐three of the 25 patients (92%, 95%CI 75–98%) were intubated with the awake videolaryngoscope‐assisted technique, with 17/23 (74%, 95%CI 54–87%) intubations achieved at the first attempt. Five patients required two and one patient, three attempts at intubation. Two patients (8%, 95%CI 2–25%) could not tolerate the procedure due to inadequate topical anaesthesia. Median (IQR [range]) times to obtain glottic view and to intubate were 19 (17–22 [10–30]) s and 49 (42–71 [33–107]) s, respectively. Traces of blood in the airway were observed in 4/25 (16%, 95%CI 6–35%) patients. Although airway management in this group of patients was expected to be difficult, successful awake intubation with the King Vision videolaryngoscope was achieved in the majority of patients within less than a minute. This study highlights a number of potential advantages of awake videolaryngoscope‐assisted intubation over other awake methods of securing the airway in patients with upper airway obstruction due to periglottic mass.     

The incidence and importance of anaemia in patients undergoing cardiac surgery in the UK – the first Association of Cardiothoracic Anaesthetists national audit

The importance and variability of pre‐operative anaemia in cardiac surgical patients across the UK is not known, and there is debate about its association with patient outcomes. The Association of Cardiothoracic Anaesthetists carried out its first national audit on anaemia and transfusion, and analysed data from 19,033 patients operated on in 12 cardiac surgical centres between 2010 and 2012; 5895 (31%) had pre‐operative anaemia. Centre‐specific prevalence of anaemia varied from 23% to 45%; anaemia was associated with older patients, diabetes and surgical risk (EuroSCORE). Nevertheless, controlling for these factors, regional variation remained an independent effect (p < 0.001). Multivariable analysis demonstrated an independent association of anaemia with transfusion (odds ratio (95% confidence interval) 2.75 (2.55–2.95), p < 0.001), mortality (1.42 (1.18–1.71), p < 0.001) and hospital stay (geometric mean ratio (95% confidence interval) 1.15 (1.13–1.17), p < 0.001). Haemoglobin concentration per se was also independently associated with worse outcomes; a 10 g.l^?1 decrease in haemoglobin was associated with a 43% increase (95% confidence interval 40–46%) in the odds of transfusion and a 16% increase (95% confidence interval 10–22%) in the odds of mortality (both p < 0.001). This large UK‐wide audit has demonstrated marked regional variation in both anaemia and transfusion, with a consistently high incidence of both. The independent association between pre‐operative anaemia and worse outcomes in UK practice has also been confirmed, and robust prospective study of anaemia treatment before cardiac surgery is required; these data will assist in designing such trials.     

Steroids to reduce the impact on delirium (STRIDE): a double-blind,randomised, placebo-controlled feasibility trial of pre-operative dexamethasone in people with hip fracture

Neuro-inflammation may be important in the pathogenesis of postoperative delirium following hip fracture surgery. Studies have suggested a potential role for steroids in reducing postoperative delirium; however, the potential efficacy and safety of pre-operative high-dose dexamethasone in this specific population is largely unknown. Conducting such a study could be challenging, considering the multidisciplinary team involvement and the emergency nature of the surgery. The aim of this study was to assess feasibility and effectiveness of dexamethasone given as early as possible following hospital admission for hip fracture, to inform whether a full-scale trial is warranted. This single-centre, randomised, double-blind, placebo-controlled study randomly allocated 79 participants undergoing hip fracture surgery to dexamethasone 20 mg or placebo pre-operatively. Eligibility and recruitment rates, timing of the intervention and adverse events were recorded. Incidence and severity of postoperative delirium were assessed using the 4AT delirium screening tool and the Memorial Delirium Assessment Scale. Postoperative pain, length of stay and mortality were also assessed. The eligibility rate for inclusion was 178/527 (34%), and 57/178 (32%) of eligible patients presented to hospital when no researcher was available (e.g. after-hours, weekends, public holidays). Recruitment was limited mainly by ethical limitations (not including patients with impaired cognition) and lack of weekend staffing. Median (IQR [range]) time from emergency department admission to drug administration was 13.3 (5.9–17.6 [1.8–139.6]) hours. There was a significant difference in delirium severity scores, favouring the dexamethasone group: median (IQR [range]) 5 (3–6 [3–7]) vs. 9 (6–13 [5–14]) in the placebo group, with the probability of superiority effect size being 0.89, p = 0.010. Delirium incidence did not differ between groups: 6/40 (15%) in the dexamethasone group vs. 9/39 (23%) in the placebo group, relative risk (95%CI) 0.65 (0.22–1.65), p = 0.360). A larger randomised controlled trial is feasible and ideally this should include people with existing cognitive impairment, seven days-a-week cover and a multicentre design.     

A randomised controlled trial of fibrinogen concentrate during scoliosis surgery

Bleeding and blood transfusion are common after scoliosis surgery. Fibrinogen is essential for blood clot formation and depletes quickly during haemorrhage. We randomly allocated 102 children 12–18 years old having surgery for idiopathic scoliosis, 51 to intra-operative fibrinogen concentrate 30 mg.kg⁻¹ (maximum 2 g) and 51 to saline placebo. Fibrinogen reduced peri-operative blood loss by a median (95%CI) volume of 155 (5–320) ml, from a median (IQR [range]) of 1035 (818–1420 [400–3030]) ml to 885 (755–1155 [270–2645]) ml, p = 0.04. Seven and four children received allogeneic red blood cell transfusion after fibrinogen and placebo, respectively, p = 0.34. There were no side-effects.