Adverse events recorded in English primary care: observational study using the General Practice Research Database

Background

More accurate and recent estimates of adverse events in primary care are necessary to assign resources for improvement of patient safety, while predictors must be identified to ameliorate patient risk.

Aim

To determine the incidence of recorded iatrogenic harm in general practice and identify risk factors for these adverse events.

Design and setting

Cross-sectional sample of 74 763 patients at 457 English general practices between 1 January 1999 and 31 December 2008, obtained from the General Practice Research Database.

Method

Patient age at study entry, sex, ethnicity, deprivation, practice region, duration registered at practice, continuity of care, comorbidities, and health service use were extracted from the data. Adverse events were defined by Read Codes for complications of care (Chapters S, T, and U). Crude and adjusted analyses were performed by Poisson regression, using generalised estimating equations.

Results

The incidence was 6.0 adverse events per 1000 person-years (95% confidence interval [CI] = 5.74 to 6.27), equivalent to eight adverse events per 10 000 consultations (n = 2 540 877). After adjustment, patients aged 65–84 years (risk ratio [RR] = 5.62, 95% CI = 4.58 to 6.91; P<0.001), with the most consultations (RR = 2.14, 95% CI = 1.60 to 2.86; P<0.001), five or more emergency admissions (RR = 2.08, 95% CI = 1.66 to 2.60; P<0.001), or the most diseases according to expanded diagnosis clusters (RR = 8.46, 95% CI = 5.68 to 12.6; P<0.001) were at greater risk of adverse events. Patients registered at their practice for the longest periods of time were less at risk of an adverse event (RR = 0.40, 95% CI = 0.35 to 0.47; P<0.001).

Conclusion

The low incidence of recorded adverse events is comparable with other studies. Temporal sequencing of risk factors and case ascertainment would benefit from data triangulation. Future studies may explore whether first adverse events predict future incidents.     

Spectral detector CT applications in advanced liver imaging

Objective:Spectral detector CT (SDCT) has many applications in advanced liver imaging. If appropriately utilized, this technology has the potential to improve image quality, provide new diagnostic information, and allow for decreased radiation dose. The purpose of this review is to familiarize radiologists with the uses of SDCT in liver imaging.Conclusion:SDCT has a variety of post-processing techniques, which can be used in advanced liver imaging and can significantly add value in clinical practice.     

Correction to: Irreversible Electroporation For Hepatocellular Carcinoma: Longer-Term Outcomes At A Single Centre

CardioVascular and Interventional Radiology - An author was inadvertently omitted from the author list. Helen Kavnoudias should be listed as third author. The added author’s name and...     

A requiem for the cholecystokinin provocation test?

Background—The cholecystokinin provocation test(CCKPT) has been claimed to predict a better symptomatic result aftercholecystectomy in patients with acalculous biliary pain.
Aims—To examine the predictive value of the CCKPTfor symptom relief after cholecystectomy in both CCKPT positive andnegative patients.
Patients and methods—Fifty eight patients withacalculous biliary pain underwent CCKPT with serial ultrasound gallbladder volumetry. CCKPT positive patients were offeredcholecystectomy; negative patients were reassessed and were offered acholecystectomy if symptoms persisted. Six months aftercholecystectomy, the CCKPT was repeated.
Results—Of 32 CCKPT positive patients, 27 underwent cholecystectomy and of these, 18 (67%) became symptom-free.Postoperatively, 20 of 25 patients converted to CCKPT negative but fiveremained CCKPT positive and were symptomatic. Of the 26 CCKPT negative patients, nine became symptom-free without cholecystectomy; six of 14 (42.8%) patients undergoing cholecystectomy became asymptomatic andremained CCKPT negative. Cholecystectomy seemed to reduce symptoms inboth groups, but there was no significant difference in the symptomaticoutcome between preoperative CCKPT positive and negative patients.
Conclusions—In this study, cholecystokininprovocation testing did not predict symptomatic benefit fromcholecystectomy and we suggest it should no longer be used in theevaluation of patients with acalculous biliary pain.

Keywords:cholecystectomy; cholecystokinin; symptoms

     

All-inside meniscal repair surgery: factors affecting the outcome

BackgroundMeniscal injury is currently a well-recognized source of knee dysfunction. While it would be ideal to repair all meniscus tears, the failure rate is significantly high, although it may be reduced by careful selection of the patients. Our objective was to assess the outcome of meniscal repair surgery and the role of simultaneous reconstruction of the anterior cruciate ligament (ACL).Results136 Meniscal repairs were performed in 122 patients with a mean age of 26.8 years. Mean follow-up duration was 9 months. 63 % of the patients underwent medial and 37 % underwent lateral meniscal repair, with failure rates of 19 % for medial and 12 % for lateral menisci. Ligament injuries were found in 61 % of the patients (n = 83). Failure of meniscal repair occurred in 14.5 % (n = 12) of the patients who had early ACL reconstruction and in 27 % (n = 22) of the patients who had delayed ACL reconstruction (p = 0.0006). The failure rate was found to be 13 % in patients who were younger than 25 years (61 %) and 15 % in patients who were older than 25 years (39 %).ConclusionThe success rate of meniscal repair was found to be significantly better when ACL reconstruction was performed simultaneously with meniscal repair.

Level of evidence

Level IV.     

The oral thrombin inhibitor dabigatran: strengths and weaknesses

Since the quest for a better replacement of warfarin started several decades ago and new compounds were brought forward to clinical trials, the concept of an ideal anticoagulant frequently became presented in lectures and articles. We have here reviewed strengths and weaknesses of the oral thrombin inhibitor dabigatran in terms of pharmacokinetics and clinical data. When strengths clearly exceed the weaknesses for any characteristic, the drug fits into the concept of an ideal anticoagulant in that domain. It is evident that dabigatran does not accomplish that concept for all characteristics but it reaches well above warfarin. We believe it is unlikely that any drug will fulfill all criteria for the ideal anticoagulant. Laboratory testing for dabigatran will not be discussed in any detail in this article, which is instead the focus of other articles from this issue of Seminars in Thrombosis & Hemostasis.     

Carbon nanostructure-reinforced SiCw/Si3N4 composite with enhanced thermal conductivity and mechanical properties

Carbon nanostructures (CNS) as a kind of reinforcement material can remarkably enhance the mechanical and thermal properties of ceramics. This research presents an analysis of the influence of CNS on the thermal conductivity and mechanical properties of SiC_w/Si₃N₄ composites. The SiC_w/Si₃N₄ composites containing various types of CNS e.g. carbon nanofibers (CNF), multi-walled carbon nanotubes (MWCNT) and graphene nano-platelets (GNP) were fabricated by hot-press sintering. XRD analysis confirmed a complete transformation of α-Si₃N₄ to β-Si₃N₄ and microstructural analysis shows a uniform distribution, as well as a pullout and bridging mechanism of CNS. The results revealed that the thermal conductivity and mechanical properties of SiC_w/Si₃N₄ composites increased with the addition of CNS. Maximum values of fracture toughness (9.70 ± 0.8 MPa m^1/2) and flexural strength (765 ± 58 MPa) have been achieved for the MWCNT-containing SiC_w/Si₃N₄ composite, whereas the maximum values of Young''s modulus (250 ± 3.8 GPa) and hardness (27.2 ± 0.9 GPa) have been achieved for the CNF-containing SiC_w/Si₃N₄ composite. Moreover, thermal conductivity also improved with the addition of CNS and reached a maximum value of 110.6 W m⁻¹ K⁻¹ for the CNF-containing SiC_w/Si₃N₄ composite. This work provides a useful approach for the fabrication of high-performance multifunctional composites for emerging engineering applications.

Carbon nanostructures (CNS) as a kind of reinforcement material can remarkably enhance the mechanical and thermal properties of ceramics.