I. K. Moppett

Development and validation of a preoperative scoring system to predict 30 day mortality in patients undergoing hip fracture surgery

BACKGROUND Hip fractures are common in the elderly and have a high 30 day postoperative mortality. The ability to recognize patients at high risk of poor outcomes before operation would be an important clinical advance. This study has determined key prognostic factors predicting 30 day mortality in a hip fracture population, and incorporated them into a scoring system to be used on admission. METHODS A cohort study was conducted at the Queens Medical Centre, Nottingham, over a period of 7 yr. Complete data were collected from 4967 patients and analysed. Forward univariate logistic regression was used to select the independent predictor variables of 30 day mortality, and then multivariate logistic regression was applied to the data to construct and validate the scoring system. RESULTS The variables found to be independent predictors of mortality at 30 days were: age (66-85 yr, > or =86 yr), sex (male), number of co-morbidities (> or =2), mini-mental test score (< or =6 out of 10), admission haemoglobin concentration (< or =10 g dl(-1)), living in an institution, and presence of malignant disease. These variables were subsequently incorporated into a risk score, the Nottingham Hip Fracture Score. The number of deaths observed at 30 days, and the number of deaths predicted by the scoring system, indicated good concordance (chi(2) test, P=0.79). The area (SE) under the receiver operating characteristic curve was 0.719 (0.018), which demonstrated a reasonable predictive value for the score. CONCLUSIONS We have developed and validated a scoring system that reliably predicts the probability of mortality at 30 days for patients after hip fracture.

Preoperative evaluation of the adult patient undergoing non-cardiac surgery: guidelines from the European Society of Anaesthesiology.

The purpose of these guidelines on the preoperative evaluation of the adult non-cardiac surgery patient is to present recommendations based on available relevant clinical evidence. The ultimate aims of preoperative evaluation are two-fold. First, we aim to identify those patients for whom the perioperative period may constitute an increased risk of morbidity and mortality, aside from the risks associated with the underlying disease. Second, this should help us to design perioperative strategies that aim to reduce additional perioperative risks. Very few well performed randomised studies on the topic are available and many recommendations rely heavily on expert opinion and are adapted specifically to the healthcare systems in individual countries. This report aims to provide an overview of current knowledge on the subject with an assessment of the quality of the evidence in order to allow anaesthetists all over Europe to integrate – wherever possible – this knowledge into daily patient care. The Guidelines Committee of the European Society of Anaesthesiology (ESA) formed a task force with members of subcommittees of scientific subcommittees and individual members of the ESA. Electronic databases were searched from the year 2000 until July 2010 without language restrictions. These searches produced 15 425 abstracts. Relevant systematic reviews with meta-analyses, randomised controlled trials, cohort studies, case–control studies and cross-sectional surveys were selected. The Scottish Intercollegiate Guidelines Network grading system was used to assess the level of evidence and to grade recommendations. The final draft guideline was posted on the ESA website for 4 weeks and the link was sent to all ESA members, individual or national (thus including most European national anaesthesia societies). Comments were collated and the guidelines amended as appropriate. When the final draft was complete, the Guidelines Committee and ESA Board ratified the guidelines.

Nottingham Hip Fracture Score as a predictor of one year mortality in patients undergoing surgical repair of fractured neck of femur

BACKGROUND Surgical repair of hip fractures is associated with high postoperative mortality. The identification of high-risk patients might be of value in aiding clinical management decisions and resource allocation. The Nottingham Hip Fracture Score (NHFS) is a scoring system validated for the prediction of 30 day mortality after hip fracture surgery. It is made up of seven independent predictors of mortality that have been incorporated into a risk score: age (66-85 and ≥86 yr); sex (male); number of co-morbidities (≥2), admission mini-mental test score (≤6 out of 10), admission haemoglobin concentration (≤10 g dl(-1)), living in an institution; and the presence of malignancy. We investigated whether the NHFS was a predictor of 1 yr mortality in patients undergoing surgical repair of fractured neck of femur. METHODS NHFS was retrospectively calculated for 6202 patients who had undergone hip fracture surgery between 1999 and 2009. One year and 30 day postoperative mortality data were collected both from hospital statistics and the Office of National Statistics. RESULTS Overall mortality was 8.3% at 30 days and 29.3% at 1 yr. An NHFS of ≤4 was considered low risk and a score of ≥5 high risk. Survival was greater in the low-risk group at 30 days [96.5% vs 86.3% (P<0.001)] and at 1 yr [84.1% vs 54.5% (P<0.001)]. CONCLUSIONS NHFS can be used to stratify the risk of 1 yr mortality after hip fracture surgery.

Outcome by mode of anaesthesia for hip fracture surgery. An observational audit of 65 535 patients in a national dataset

Large observational studies of accurate data can provide similar results to more arduous and expensive randomised controlled trials. In 2012, the National Hip Fracture Database extended its dataset to include ‘type of anaesthesia’ data fields. We analysed 65 535 patient record sets to determine differences in outcome. Type of anaesthesia was recorded in 59 191 (90%) patients. Omitting patients who received both general and spinal anaesthesia or in whom an uncertain type of anaesthesia was recorded, there was no significant difference in either cumulative five‐day (2.8% vs 2.8%, p = 0.991) or 30‐day (7.0% vs 7.5%, p = 0.053) mortality between 30 130 patients receiving general anaesthesia and 22 999 patients receiving spinal anaesthesia, even when 30‐day mortality was adjusted for age and ASA physical status (p = 0.226). Mortality within 24 hours after surgery was significantly higher among patients receiving cemented compared with uncemented hemiarthroplasty (1.6% vs 1.2%, p = 0.030), suggesting excess early mortality related to bone cement implantation syndrome. If these data are accurate, then either there is no difference in 30‐day mortality between general and spinal anaesthesia after hip fracture surgery per se, and therefore future research should focus on how to make both types of anaesthesia safer, or there is a difference, but mortality is not the correct outcome to measure after anaesthesia, and therefore future research should focus on differences between general and spinal anaesthesia. These could include more anaesthesia‐sensitive outcomes, such as hypotension, pain, postoperative confusion, respiratory infection and mobilisation.

Nottingham Hip Fracture Score: longitudinal and multi-centre assessment

BACKGROUND The Nottingham Hip Fracture Score (NHFS) was developed and validated in a single centre in 2007 as a predictor of 30 day mortality. It has subsequently been shown to predict longer term and functional outcomes. We wished to assess the ability of NHFS to predict outcomes in other centres and to investigate the change in outcome after hip fracture over time. METHODS The NHFS was calculated for all patients with data from three UK hip fracture units: Peterborough (1992-2009), Brighton (2008-9), and Nottingham (2000-9) including 4804, 585, and 1901 patients, respectively. The logistic regression was used to recalibrate the NHFS to 30 day mortality across the three units using a random selection of 50% of the data set. Calibration was assessed using the Hosmer-Lemeshow goodness of fit. RESULTS The median (inter-quartile range) NHFS values were Peterborough [4.0 (1-6)], Brighton [5.0 (3-7)], and Nottingham [5.0 (3-7)]. There was no correlation between 30 day mortality and time (R(2)=0.05, P=0.115). The proportion of patients with NHFS ≥ 4 showed a weak correlation with time (R(2)=0.2, P=0.003). The original NHFS equation overestimates mortality in the higher-risk groups. A modified equation shows good calibration for all three centres {30 day mortality (%)=100/1+e([(5.012 × (NHFS × 0.481)])}. The hospital was not a predictor of 30 day mortality. CONCLUSIONS The NHFS, with an updated equation, is a robust predictor of 30 day mortality after hip fracture repair in geographically distinct UK centres.

Effects of norepinephrine and glyceryl trinitrate on cerebral haemodynamics: transcranial Doppler study in healthy volunteers

BACKGROUND The effects of vasoactive substances on cerebral haemodynamics are not fully known. We studied the effects of norepinephrine and glyceryl trinitrate (GTN) on cerebral haemodynamics in healthy volunteers. METHODS The effects of norepinephrine (n=10) and GTN (n=10) on the middle cerebral artery flow velocity (MCAFV), cerebral autoregulation, reactivity to carbon dioxide, and estimated cerebral perfusion pressure (eCPP) were studied using transcranial Doppler ultrasound. Established methods were used for calculating zero flow pressure (ZFP). Measurements were made at baseline, and after i.v. infusion of the study drug to the endpoints of 25% increase in mean arterial pressure (MAP) for norepinephrine (0.02-0.1 microg kg(-1) min(-1)), or 15% decrease in MAP for GTN (0.5-2.5 microg kg(-1) min(-1)). RESULTS The MCAFV remained unchanged with norepinephrine, but decreased slightly with GTN {from [median (inter-quartile range)] 53 (38, 62) to 48 (33, 52) cm s(-1)}. Cerebrovascular reactivity did not change significantly with either drug. The eCPP did not change significantly with norepinephrine, but increased significantly with GTN [from 49 (32, 54) to 62 (47, 79) mm Hg]. ZFP increased with norepinephrine [from 39 (28, 48) to 56 (46, 62) mm Hg] and decreased with GTN [from 35 (30, 49) to 12 (-7, 20) mm Hg]. CONCLUSIONS Norepinephrine, despite increasing arterial pressure, did not increase the eCPP. The eCPP increased significantly with GTN, despite decreased MAP. Cerebral vascular tone is an important determinant of CPP during pharmacologically induced changes in arterial pressure.

A systematic review of pre-operative anaemia and blood transfusion in patients with fractured hips.

We systematically reviewed the observational associations of anaemia with outcomes and the effects of interventions to increase haemoglobin concentrations following hip fracture in older people. Anaemia on hospital admission was associated with increased mortality, relative risk 1.64 (95% CI 1.47–1.82), p < 0.0001. After adjustment for co‐morbidities, the association of anaemia with increased mortality remained in four of eight observational studies. There was no association of postoperative transfusion with mortality after adjusting for covariates. Transfusion at 80 g.l−1 vs 100 g.l−1 increased acute myocardial infarction, relative risk 1.67 (95% CI 1.01–2.77), p = 0.05. Transfusion threshold was not associated with differences in other outcomes. There were insufficient high‐quality studies to inform pre‐operative blood transfusion or the use of peri‐operative iron or erythropoietin. Studies for most interventions recruited too few participants to determine effects on infections, mortality or function.

Secondary analysis of outcomes after 11,085 hip fracture operations from the prospective UK Anaesthesia Sprint Audit of Practice (ASAP-2)

We re‐analysed prospective data collected by anaesthetists in the Anaesthesia Sprint Audit of Practice (ASAP‐1) to describe associations with linked outcome data. Mortality was 165/11,085 (1.5%) 5 days and 563/11,085 (5.1%) 30 days after surgery and was not associated with anaesthetic technique (general vs. spinal, with or without peripheral nerve blockade). The risk of death increased as blood pressure fell: the odds ratio (95% CI) for mortality within five days after surgery was 0.983 (0.973–0.994) for each 5 mmHg intra‐operative increment in systolic blood pressure, p = 0.0016, and 0.980 (0.967–0.993) for each mmHg increment in mean pressure, p = 0.0039. The equivalent odds ratios (95% CI) for 30‐day mortality were 0.968 (0.951–0.985), p = 0.0003 and 0.976 (0.964–0.988), p = 0.0001, respectively. The lowest systolic blood pressure after intrathecal local anaesthetic relative to before induction was weakly correlated with a higher volume of subarachnoid bupivacaine: r2 −0.10 and −0.16 for hyperbaric and isobaric bupivacaine, respectively. A mean 20% relative fall in systolic blood pressure correlated with an administered volume of 1.44 ml hyperbaric bupivacaine. Future research should focus on refining standardised anaesthesia towards administering lower doses of spinal (and general) anaesthesia and maintaining normotension.

Evolution of the hip fracture population: time to consider the future? A retrospective observational analysis

Objective To examine how the population with fractured neck of femur has changed over the last decade and determine whether they have evolved to become a more physically and socially dependent cohort. Design Retrospective cohort study of prospectively collected Standardised Audit of Hip Fractures of Europe data entered on to an institutional hip fracture registry. Participants 10 044 consecutive hip fracture admissions (2000–2012). Setting A major trauma centre in the UK. Results There was a generalised increase in the number of admissions between 2000 (n=740) and 2012 (n=810). This increase was non-linear and best described by a quadratic curve. Assuming no change in the prevalence of hip fracture over the next 20 years, our hospital is projected to treat 871 cases in 2020 and 925 in 2030. This represents an approximate year-on-year increase of just over 1%. There was an increase in the proportion of male admissions over the study period (2000: 174 of 740 admissions (23.5%); 2012: 249 of 810 admissions (30.7%)). This mirrored national census changes within the geographical area during the same period. During the study period there were significant increases in the numbers of patients admitted from their own home, the proportion of patients requiring assistance to mobilise, and the proportion of patients requiring help with basic activities of daily living (all p<0.001). There was also a twofold to fourfold increase in the proportion of patients admitted with a diagnosis of cardiovascular disease, renal disease, diabetes and polypharmacy (use of >4 prescribed medications; all p<0.001). Conclusions The expanding hip fracture population has increasingly complex medical, social and rehabilitation care needs. This needs to be recognised so that appropriate healthcare strategies and service planning can be implemented. This epidemiological analysis allows projections of future service need in terms of patient numbers and dependency.

Comparison of EMLA and lidocaine iontophoresis for cannulation analgesia

Background and objective: Eutectic mixture of local anaesthetic cream and lidocaine iontophoresis are effective in providing analgesia for peripheral venous cannulation with small gauge cannulae in adults and children. The objective of this study was to compare the analgesic efficacy of the two techniques directly in patients using larger cannulae. Methods: In a double-blind, randomized, controlled study we compared the two techniques directly. Twenty-eight patients had the eutectic mixture of local anaesthetic cream applied to the dorsum of one hand for 60 min followed by sham iontophoresis (group EMLA); the other hand had a sham cream applied for 60 min followed by 10 min of 2 mA iontophoresis with lidocaine 4% and epinephrine 1 in 50 000 (group iontophoresis). Within 5 min of completion of iontophoresis an anaesthetist, unaware of treatment allocation, inserted 18-G venous cannulae into veins of both hands. The patient then scored the amount of pain on cannulation using a 10 point verbal rating scale. Results: Eight patients were excluded from analysis due to failed cannulation (two group EMLA, two group iontophoresis), intolerable burning sensation from iontophoresis (one), protocol violation (one), and changes in surgical schedule (two). Pain scores were lower for the EMLA treated hand than for the iontophoresis side (median (range) 1 (0-7) vs. 3 (0-6); P = 0.023). Erythema and paraesthesia were common but short lived on the iontophoresis side. Conclusions: Although lidocaine iontophoresis is effective more quickly than the eutectic mixture of local anaesthetic cream, the superior quality of analgesia produced by the eutectic mixture in this study should be borne in mind if these treatments are used electively.