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.     

Borderline anaemia and postoperative outcome in women undergoing major abdominal surgery: a retrospective cohort study

Pre-operative anaemia is typically diagnosed with a haemoglobin concentration < 120 g.l⁻¹ for women and < 130 g.l⁻¹ for men on the basis of limited evidence. This retrospective cohort study stratified women undergoing elective, major abdominal surgery based on pre-operative haemoglobin concentration: anaemic (< 120 g.l⁻¹); borderline anaemic (120–129 g.l⁻¹); and non-anaemic (> 130 g.l⁻¹). Data from 1554 women were analysed. Women with borderline anaemia had a greater incidence of postoperative complications (55 (16%) vs. 110 (11%); p = 0.026), longer duration of hospital stay (median (IQR [range]) 3 (1–6 [0–69]) days vs. 2 (1–5 [0–80]) days; p = 0.017) and fewer days alive and out of hospital at postoperative day 30 (median (IQR [range]) 27 (23–29 [0–30]) vs. 28 (25–29 [0–30]) days; p = 0.017) compared with non-anaemic women. However, after matched cohort analysis, these outcome differences no longer remained statistically significant. After multivariable adjustment for procedure, Charlson comorbidity index and patient age, a negative relationship between logarithmic pre-operative haemoglobin concentration and duration of stay was found (parameter estimate (standard error) −0.006 (0.003) vs. 0.003 (0.003) for a haemoglobin concentration < 130 g.l⁻¹ vs. > 130 g.l⁻¹, respectively; p = 0.03); the difference in duration of stay was approximately 50% greater for women with a haemoglobin concentration of 120 g.l⁻¹ compared with those with a haemoglobin concentration of 130 g.l⁻¹. Although the contribution of borderline anaemia to the incidence of postoperative complications is uncertain, the current diagnostic criteria should be re-assessed.     

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 association between iron deficiency and outcomes: a secondary analysis of the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial

In the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial, the use of intravenous iron did not reduce the need for blood transfusion or reduce patient complications or length of hospital stay. As part of the trial protocol, serum was collected at randomisation and on the day of surgery. These samples were analysed in a central laboratory for markers of iron deficiency. We performed a secondary analysis to explore the potential interactions between pre-operative markers of iron deficiency and intervention status on the trial outcome measures. Absolute iron deficiency was defined as ferritin <30 μg.l⁻¹; functional iron deficiency as ferritin 30–100 μg.l⁻¹ or transferrin saturation < 20%; and the remainder as non-iron deficient. Interactions were estimated using generalised linear models that included different subgroup indicators of baseline iron status. Co-primary endpoints were blood transfusion or death and number of blood transfusions, from randomisation to 30 days postoperatively. Secondary endpoints included peri-operative change in haemoglobin, postoperative complications and length of hospital stay. Most patients had iron deficiency (369/452 [82%]) at randomisation; one-third had absolute iron deficiency (144/452 [32%]) and half had functional iron deficiency (225/452 [50%]). The change in pre-operative haemoglobin with intravenous iron compared with placebo was greatest in patients with absolute iron deficiency, mean difference 8.9 g.l⁻¹, 95%CI 5.3–12.5; moderate in functional iron deficiency, mean difference 2.8 g.l⁻¹, 95%CI −0.1 to 5.7; and with little change seen in those patients who were non-iron deficient. Subgroup analyses did not suggest that intravenous iron compared with placebo reduced the likelihood of death or blood transfusion at 30 days differentially across subgroups according to baseline ferritin (p = 0.33 for interaction), transferrin saturation (p = 0.13) or in combination (p = 0.45), or for the number of blood transfusions (p = 0.06, 0.29, and 0.39, respectively). There was no beneficial effect of the use of intravenous iron compared with placebo, regardless of the metrics to diagnose iron deficiency, on postoperative complications or length of hospital stay.     

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).     

Anaemia in cardiac surgery – a retrospective review of a centre's experience with a pre-operative intravenous iron clinic

Pre-operative anaemia is associated with higher rates of transfusion and worse outcomes, including prolonged hospital stay, morbidity and mortality. Iron deficiency is associated with significantly lower haemoglobin levels throughout the peri-operative period and more frequent blood transfusion. Correction of iron stores before surgery forms part of the first pillar of patient blood management. We established a pre-operative anaemia clinic to aid identification and treatment of patients with iron deficiency anaemia scheduled for elective cardiac surgery. We present a retrospective observational review of our experience from January 2017 to December 2019. One-hundred and ninety patients received treatment with intravenous iron, a median of 21 days before cardiac surgery. Of these, 179 had a formal laboratory haemoglobin level measured before surgery, demonstrating a median rise in haemoglobin of 8.0 g.l^-1. Patients treated with i.v. iron demonstrated a significantly higher incidence of transfusion (60%) compared with the non-anaemic cohort (22%) during the same time period, p < 0.001. Significantly higher rates of new requirement for renal replacement therapy (6.7% vs. 0.6%, p < 0.001) and of stroke (3.7% vs. 1.2%, p = 0.010) were also seen in this group compared with those without anaemia, although there was no significant difference in in-hospital mortality (1.6% vs. 0.8%, p = 0.230). In patients where the presenting haemoglobin was less than 130 g.l^-1, but there was no intervention or treatment, there was no difference in rates of transfusion or of complications compared with the anaemic group treated with iron. In patients with proven iron deficiency anaemia, supplementation with intravenous iron showed only a modest effect on haemoglobin and this group still had a significantly higher transfusion requirement than the non-anaemic cohort. Supplementation with intravenous iron did not improve outcomes compared with patients with anaemia who did not receive intravenous iron and did not reduce peri-operative risk to non-anaemic levels. Questions remain regarding identification of patients who will receive most benefit, the use of concomitant treatment with other agents, and the optimum time frames for treatment in order to produce benefit in the real-world setting.     

Anaemia among intensive care unit survivors and association with days alive and at home: an observational study

Anaemia is highly prevalent at the time of intensive care unit discharge and is persistent for a high proportion of intensive care unit survivors. Whether anaemia is a driver of impaired recovery after critical illness is uncertain. The aim of this study was to test the hypothesis that, in adult intensive care survivors, anaemia at the time of intensive care unit discharge independently predicts decreased days at home-90. This retrospective cohort study was conducted in a tertiary intensive care unit in Perth, Western Australia. All patients aged ≥ 16 years, discharged alive from their index intensive care unit admission and without documented treatment limitations were included. Median (IQR [range]) age of the 6358 participants was 61 (46–72 [16–95]) years and included 3385 (53.2%) unplanned admissions. Intensive care unit discharge with a haemoglobin concentration < 100 g.l^-1 occurred in 2886 (45.4%) patients, a threshold that identified a cohort with significantly lower days at home-90 (median (IQR [range]) 80 (64–85 [0–90]) days vs. 85 (77–88 [0–90]) days (median difference 5 days, 95%CI 4.4–5.5, p < 0.0001). The association followed a severity-response relationship with more severe anaemia predicting lower days at home-90. When accounting for prespecified covariates including admission haemoglobin concentration and red blood cell transfusion, anaemia at intensive care unit discharge remained a significant predictor of decreased days at home-90, relative risk 0.96 (0.93–0.98), p < 0.002. These findings support the need for interventional trials investigating whether this risk is modifiable.     

Quantitative evaluation of aerosol generation during manual facemask ventilation

Manual facemask ventilation, a core component of elective and emergency airway management, is classified as an aerosol-generating procedure. This designation is based on one epidemiological study suggesting an association between facemask ventilation and transmission during the SARS-CoV-1 outbreak in 2003. There is no direct evidence to indicate whether facemask ventilation is a high-risk procedure for aerosol generation. We conducted aerosol monitoring during routine facemask ventilation and facemask ventilation with an intentionally generated leak in anaesthetised patients. Recordings were made in ultraclean operating theatres and compared against the aerosol generated by tidal breathing and cough manoeuvres. Respiratory aerosol from tidal breathing in 11 patients was reliably detected above the very low background particle concentrations with median [IQR (range)] particle counts of 191 (77–486 [4–1313]) and 2 (1–5 [0–13]) particles.l^-1, respectively, p = 0.002. The median (IQR [range]) aerosol concentration detected during facemask ventilation without a leak (3 (0–9 [0–43]) particles.l^-1) and with an intentional leak (11 (7–26 [1–62]) particles.l^-1) was 64-fold (p = 0.001) and 17-fold (p = 0.002) lower than that of tidal breathing, respectively. Median (IQR [range]) peak particle concentration during facemask ventilation both without a leak (60 (0–60 [0–120]) particles.l^-1) and with a leak (120 (60–180 [60–480]) particles.l^-1) were 20-fold (p = 0.002) and 10-fold (0.001) lower than a cough (1260 (800–3242 [100–3682]) particles.l^-1), respectively. This study demonstrates that facemask ventilation, even when performed with an intentional leak, does not generate high levels of bioaerosol. On the basis of this evidence, we argue facemask ventilation should not be considered an aerosol-generating procedure.     

Pre‐operative anaemia,intra‐operative hepcidin concentration and acute kidney injury after cardiac surgery: a retrospective observational study

Acute kidney after cardiac surgery is more common in anaemic patients, whereas haemolysis during cardiopulmonary bypass may lead to iron‐induced renal injury. Hepcidin promotes iron sequestration by macrophages: hepcidin concentration is reduced by anaemia and increased by inflammation. We analysed the associations in 525 patients between pre‐operative anaemia (haemoglobin < 130 g.l^?1 in men and < 120 g.l^?1 in women), intra‐operative hepcidin concentration and acute kidney injury (dialysis or > 26.4 μmol.l^?1 or > 50% creatinine increase during the first two days after cardiac surgery. Rates of pre‐operative anaemia and postoperative kidney injury were 109/525 (21%) and 36/525 (7%), respectively. The median (IQR [range]) intra‐operative hepcidin concentration was 20 (10–33 [0–125]) μg.l^?1 and was lower in anaemic patients than those who were not: 15 (4–28 [0–125]) μg.l^?1 vs. 21 (12–33 [0–125]) μg.l^?1, respectively, p = 0.002. Four variables were independently associated with postoperative kidney injury, for which the beta‐coefficients (SE) were: minutes on cardiopulmonary bypass, 0.016 (0.004), p < 0.001; intra‐operative hepcidin concentration, 0.032 (0.008), p < 0.001; pre‐operative anaemia, 1.97 (0.56), p < 0.001; and Cleveland clinic risk score, 0.88 (0.35), p = 0.005. Contrary to generally increased rates of kidney injury in patients with higher hepcidin concentrations, rates of kidney injury in anaemic patients were lower in patients with higher hepcidin concentrations, beta‐coefficient (SE) ?0.037 (0.01), p = 0.007. In cardiac surgical patients the rate of postoperative acute kidney injury predicted by the Cleveland risk score might be adjusted for pre‐operative anaemia and intra‐operative cardiopulmonary bypass time and hepcidin concentration. Pre‐operative correction of anaemia, reduction in intra‐operative bypass time and modification of iron homeostasis and hepcidin concentration might reduce acute kidney injury.     

A randomised clinical trial comparing the flexible fibrescope and the Pentax Airway Scope (AWS)® for awake oral tracheal intubation

We compared awake fibreoptic intubation with awake intubation using the Pentax Airway Scope^® in 40 adult patients. Sedation was achieved using a target‐controlled remifentanil infusion of 1–5 ng.ml^?1 and midazolam. The airway was anaesthetised with lidocaine spray and gargle. The total procedure time – a composite of sedation time, topical anaesthesia time and intubation time – was recorded. The operator's impression of the ease of the procedure and the patients' reported comfort were recorded on a 0–100 mm visual analogue scale. The median (IQR [range]) for total procedure time was 900 (739–1059 [616–1215]) s with the fibrescope and 651 (601–720 [498–900]) s with the Pentax Airway Scope (p = 0.0001). The median (IQR [range]) intubation time was 420 (283–480 [120–608]) s with the fibrescope and 183 (144–220 [107–420]) s with the Pentax Airway Scope (p = 0.0002). The median (IQR [range]) visual analogue scores for the operator's ease of intubation for the fibrescope and Pentax Airway Scope were 83.6 (72.0–98.0 [49.0–100.0]) and 86.8 (84.0–91.0 [61.0–100.0]), respectively (p = 0.3507). The median (IQR [range]) visual analogue score for patient comfort was 85.5 (81.0–97.0 [69.0–100.0]) and 79.4 (74.0–85.0 [59.0–100.0]) for the fibrescope and Pentax Airway Scope, respectively (p = 0.06). Total procedure time was significantly shorter with the Pentax Airway Scope compared with the fibrescope, with no difference in procedure difficulty or patient discomfort.     

A quantitative evaluation of aerosol generation during supraglottic airway insertion and removal

Many guidelines consider supraglottic airway use to be an aerosol-generating procedure. This status requires increased levels of personal protective equipment, fallow time between cases and results in reduced operating theatre efficiency. Aerosol generation has never been quantitated during supraglottic airway use. To address this evidence gap, we conducted real-time aerosol monitoring (0.3–10-µm diameter) in ultraclean operating theatres during supraglottic airway insertion and removal. This showed very low background particle concentrations (median (IQR [range]) 1.6 (0–3.1 [0–4.0]) particles.l⁻¹) against which the patient’s tidal breathing produced a higher concentration of aerosol (4.0 (1.3–11.0 [0–44]) particles.l⁻¹, p = 0.048). The average aerosol concentration detected during supraglottic airway insertion (1.3 (1.0–4.2 [0–6.2]) particles.l⁻¹, n = 11), and removal (2.1 (0–17.5 [0–26.2]) particles.l⁻¹, n = 12) was no different to tidal breathing (p = 0.31 and p = 0.84, respectively). Comparison of supraglottic airway insertion and removal with a volitional cough (104 (66–169 [33–326]), n = 27), demonstrated that supraglottic airway insertion/removal sequences produced <4% of the aerosol compared with a single cough (p < 0.001). A transient aerosol increase was recorded during one complicated supraglottic airway insertion (which initially failed to provide a patent airway). Detailed analysis of this event showed an atypical particle size distribution and we subsequently identified multiple sources of non-respiratory aerosols that may be produced during airway management and can be considered as artefacts. These findings demonstrate supraglottic airway insertion/removal generates no more bio-aerosol than breathing and far less than a cough. This should inform the design of infection prevention strategies for anaesthetists and operating theatre staff caring for patients managed with supraglottic airways.     

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.     

Platelet count and transfusion requirements during moderate or severe postpartum haemorrhage

Limited data exist on platelet transfusion during postpartum haemorrhage. We retrospectively analysed a consecutive cohort from a single centre of 347 women with moderate or severe postpartum haemorrhage, transfused according to national guidelines. Twelve (3%) women required a platelet transfusion. There were no differences between women who did and did not receive platelets with respect to age, mode of initiation of labour or mode of delivery. Women receiving a platelet transfusion had a lower median (IQR [range]) platelet count at study entry than women who did not receive platelets before haemorrhage (135 (97–175 [26–259])×10⁹.l^?1 vs 224 (186–274 [91–1006])×10⁹.l^?1), respectively), and at diagnosis of postpartum haemorrhage (median 114 (78–153 [58–238])×10⁹.l^?1 vs 193 (155–243 [78–762])×10⁹.l^?1 respectively). Six women were thrombocytopenic pre‐delivery. The cause of haemorrhage that was associated with the highest rate of platelet transfusion was placental abruption, with three of 14 women being transfused. If antenatal thrombocytopenia or consumptive coagulopathy were not present, platelets were only required for haemorrhage > 5000 ml. Early formulaic platelet transfusion would have resulted in many women receiving platelets unnecessarily. Using current guidelines, the need for platelet transfusion is uncommon without antenatal thrombocytopenia, consumptive coagulopathy or haemorrhage > 5000 ml. We found no evidence to support early fixed‐ratio platelet transfusion.     

Levobupivacaine – dextran mixture for transversus abdominis plane block and rectus sheath block in patients undergoing laparoscopic colectomy: a randomised controlled trial

We performed a randomised controlled double‐blinded study of patients having laparoscopic colectomy with bilateral transversus abdominis plane block plus rectus sheath block, comparing a control group receiving 80 ml levobupivacaine 0.2% in saline with a dextran group receiving 80 ml levobupivacaine 0.2% in 8% low‐molecular weight dextran. Twenty‐seven patients were studied in each group. The mean (SD) maximum plasma concentration of levobupivacaine in the control group (1410 (322) ng.ml^?1) was higher than the dextran group (1141 (287) ng.ml^?1; p = 0.004), and was reached more quickly (50.6 (30.2) min vs 73.2 (24.6) min; p = 0.006). The area under the plasma concentration–time curve from 0 min to 240 min in the control group (229,124 (87,254) ng.min.ml^?1) was larger than in the dextran group (172,484 (50,502) ng.min.ml^?1; p = 0.007). The median (IQR [range]) of the summated numerical pain rating score at rest during the first postoperative 24 h in the control group (16 (9–20 [3–31]) was higher than in the dextran group (8 (2–11 [0–18]); p = 0.0001). In this study, adding dextran to levobupivacaine decreased the risk of levobupivacaine toxicity while providing better analgesia.     

Functional recovery after discharge in enhanced recovery video-assisted thoracoscopic lobectomy: a pilot prospective cohort study

Little is known about functional recovery following patient discharge in an established enhanced recovery programme after video-assisted thoracoscopic lobectomy. We conducted a single-centre pilot prospective observational cohort study. We hypothesised that patients achieved early functional recovery after discharge. A total of 32 patients aged ≥ 18 years were enrolled. A digital device was used for objective activity measurements, and patient-reported outcomes were collected as subjective measurements. Primary outcomes were the difference in physical activity; sleep duration; pain; fatigue; and average quality of life scores between pre-operative baseline and 7 days following discharge. The secondary outcome was the reason for reduced daily activity during the first 7 days after discharge. Median (IQR [range]) length of stay was 3 (2–5 [1–13]) days. Up to post-discharge day 7, total, lower intensity and moderate-to-vigorous activities were lower than pre-operative activity (p < 0.001; p = 0.005 and p = 0.027, respectively). Numerical rating scale (0–10) pain scores increased postoperatively at rest (mean difference 1.2, p < 0.001) and during walking (mean difference 1.4, p < 0.001). Fatigue assessed by the Christensen Fatigue Scale (1–10) was also increased postoperatively (mean difference 1.7, p = 0.001). There was a reduction in quality of life scores, while sedentary activity and sleep duration were unchanged postoperatively. Dominant reasons for not recovering daily activity included fatigue in 43% and pain in 33% of patients. Despite compliance with an enhanced recovery programme with a median length of hospital stay of 3 days after video-assisted thoracoscopic lobectomy, functional recovery was not achieved within 7 days after hospital discharge. Reduction in postoperative pain and fatigue are important factors to enhance functional recovery.     

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.     

Peri‐operative management of patients with type‐2 diabetes mellitus undergoing non‐cardiac surgery using liraglutide,glucose–insulin–potassium infusion or intravenous insulin bolus regimens: a randomised controlled trial

In this open‐label multicentre randomised controlled trial, we investigated three peri‐operative treatment strategies to lower glucose and reduce the need for rescue insulin in patients aged 18–75 years with type‐2 diabetes mellitus undergoing non‐cardiac surgery. Patients were randomly allocated using a web‐based randomisation program to premedication with liraglutide (liraglutide group), glucose–insulin–potassium infusion (insulin infusion group) or insulin bolus regimen (insulin bolus group), targeting a glucose < 8.0 mmol.l^?1. The primary outcome was the between group difference in median glucose levels 1 h after surgery. We analysed 150 patients (liraglutide group n = 44, insulin infusion group n = 53, insulin bolus group n = 53) according to the intention‐to‐treat principle. Median (IQR [range]) plasma glucose 1 h postoperatively was lower in the liraglutide group compared with the insulin infusion and insulin bolus groups (6.6 (5.6–7.7 [4.2–13.5]) mmol.l^?1 vs. 7.5 (6.4–8.3 [3.9–16.6]) mmol.l^?1 (p = 0.026) and 7.6 (6.4–8.9 [4.7–13.2]) mmol.l^?1) p = 0.006, respectively). The incidence of hypoglycaemia and postoperative complications did not differ between the groups. Six patients had pre‐operative nausea in the liraglutide group, of which two had severe nausea, compared with no patients in the insulin infusion and insulin bolus groups (p = 0.007). The pre‐operative administration of liraglutide stabilised peri‐operative plasma glucose levels and reduced peri‐operative insulin requirements, at the expense of increased pre‐operative nausea rates.     

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.     

The association of abdominal muscle with outcomes after scheduled abdominal aortic aneurysm repair

Sarcopenia is the degenerative loss of core muscle mass. It is an aspect of frailty, which is associated with increased rates of peri‐operative harm. We assessed the association of the cross‐sectional areas of abdominal muscles, including psoas, with survival during a median (IQR [range]) follow‐up of 3.8 (3.2–4.4 [0.0–5.1]) years after scheduled endovascular (132) or open (5) abdominal aortic aneurysm repair in 137 patients. In multivariate analysis, mortality hazard (95%CI) was independently associated with: age, 1.06 (1.01–1.13) per year, p = 0.03; and the adjusted area of the left psoas muscle, 0.94 (0.81–1.01) per mm².kg^?0.83, p = 0.08. Shortened hospital stay was independently associated with haemoglobin concentration and adjusted left psoas muscle area, hazard ratio (95%) 1.01 (1.00–1.02) per g.l^?1 and 1.05 (1.02–1.07) per mm².kg^?0.83, p = 0.04 and 0.001, respectively.     

Simulation as a tool to improve the safety of pre‐hospital anaesthesia – a pilot study*

We conducted a pilot study of the effects of simulation as a tool for teaching doctor‐paramedic teams to deliver pre‐hospital anaesthesia safely. Participants undertook a course including 43 full immersion, high‐fidelity simulations. Twenty videos taken from day 4 and days 9/10 of the course were reviewed by a panel of experienced pre‐hospital practitioners. Participants’ performance at the beginning and the end of the course was compared. The total time from arrival to inflation of the tracheal tube cuff was longer on days 9/10 than on day 4 (mean (SD) 14 min 52 s (2 min 6 s) vs 11 min 28 s (1 min 54 s), respectively; p = 0.005), while the number of safety critical events per simulation were fewer (median (IQR [range]) 1.0 (0–1.8 [0–2]) vs 3.5 (1.5–4.8 [0–8], respectively; p = 0.011). Crew resource management behaviours also improved in later simulations. On a personal training needs analysis, participants reported increased confidence after the course.