Chronic deep vein thrombosis.

Deep vein thrombosis (DVT) is an important cause of short-term mortality and long-term morbidity. Although acute DVT is often well managed, there is uncertainty in the management of chronic DVT which is increasingly being noted among patients presenting with similar symptoms to their initial DVT. The presence of a residual venous clot can be a problem for both physicians and patients fearing the risk of emboli to the same extent as the acute DVT. There are also issues in the accurate diagnosis and appropriate management of chronic DVT, which is the focus of the second part of this review.

Iliofemoral deep vein thrombosis and the problem of post-thrombotic syndrome.

Deep vein thrombosis (DVT) is an important cause of short-term mortality and long-term morbidity. Among the different presentations of DVT, thrombus in the iliofemoral veins may be considered the severest form. Although anticoagulation is the mainstay of the management of iliofemoral thrombosis, despite adequate anticoagulant treatment, complications including post-thrombotic syndrome is not uncommon. The latter is often overlooked but can cause considerable morbidity to the affected individuals. Preventing this condition remains a challenge but recent clinical trials of catheter directed thrombolysis and elasticated compression stockings provide some advance in this context. In this article, with the aid of a clinical case, we review the particular considerations to take into account when managing patients with an iliofemoral DVT.

Evidence for non-communicable diseases: analysis of Cochrane reviews and randomised trials by World Bank classification.

INTRODUCTION: Prevalence of non-communicable diseases (NCDs) is increasing globally, with the greatest projected increases in low-income and middle-income countries. We sought to quantify the proportion of Cochrane evidence relating to NCDs derived from such countries. METHODS: We searched the Cochrane database of systematic reviews for reviews relating to NCDs highlighted in the WHO NCD action plan (cardiovascular, cancers, diabetes and chronic respiratory diseases). We excluded reviews at the protocol stage and those that were repeated or had been withdrawn. For each review, two independent researchers extracted data relating to the country of the corresponding author and the number of trials and participants from countries, using the World Bank classification of gross national income per capita. RESULTS: 797 reviews were analysed, with a reported total number of 12 340 trials and 10 937 306 participants. Of the corresponding authors 90% were from high-income countries (41% from the UK). Of the 746 reviews in which at least one trial had met the inclusion criteria, only 55% provided a summary of the country of included trials. Analysis of the 633 reviews in which country of trials could be established revealed that almost 90% of trials and over 80% of participants were from high-income countries. 438 (5%) trials including 1 145 013 (11.7%) participants were undertaken in low-middle income countries. We found that only 13 (0.15%) trials with 982 (0.01%) participants were undertaken in low-income countries. Other than the five Cochrane NCD corresponding authors from South Africa, only one other corresponding author was from Africa (Gambia). DISCUSSION: The overwhelming body of evidence for NCDs pertains to high-income countries, with only a small number of review authors based in low-income settings. As a consequence, there is an urgent need for research infrastructure and funding for the undertaking of high-quality trials in this area.

Interscalene brachial plexus block: assessment of the needle angle needed to enter the spinal canal.

Attempts were made to place 8-cm 22G needles into the spinal canals of four preserved cadavers using the skin entry point most commonly associated with the lateral interscalene brachial plexus block or Winnie approach (that is, at the level of the cricoid cartilage). Eleven successful attempts were confirmed by computed tomography. Needle angles that were cephalad, transverse or slightly caudad were associated with entry into the spinal canal at depths of 5.0 cm or less from the skin. The only needle entry into the spinal canal with a needle angle of > 50 degrees to the transverse plane (< 40 degrees to the sagittal plane) entered the intervertebral foramen at a depth of 7.7 cm from the skin. We conclude that the use of markedly caudad angulations of needles no longer than 5.0 cm may minimise the chances of spinal canal entry and spinal cord damage.

Postoperative shoulder surgery initiative (POSSI): an interim report of major shoulder surgery as a day case procedure.

BACKGROUND: There are logistical and financial advantages to undertaking shoulder surgery in a day case setting. However, this approach is limited by postoperative pain being inadequately controlled by oral medication alone. We describe a pilot study investigating the feasibility and acceptance of community based continuous interscalene brachial plexus blockade (CIBPB) to provide effective analgesia for day case shoulder surgery. METHODS: Phase 1 consisted of five patients who received CIBPB for shoulder surgery. Following an overnight hospital stay they were assessed for discharge home with the interscalene catheter in situ. Once the safety and feasibility of the approach was documented, five more patients were recruited to Phase 2. These patients had the adequacy of analgesia assessed in the postoperative period and were discharged home on the same day as surgery. A district nurse visited twice daily and removed the catheter on the third day. Patient satisfaction was assessed using a discovery interview. RESULTS: Nine of the 10 patients experienced good analgesia. One patient was re-admitted because the catheter fell out. No patient experienced complications and the discovery interviews showed that the patients were satisfied with their management and pleased to be treated as a day case. CONCLUSIONS: POSSI proved that it was feasible to manage these patients in the community with support and training of the district nurses. Although extra community nursing hours are required, this technique has the potential for significant cost benefits with at least three bed days saved per patient.

Evaluation of an insulated Tuohy needle system for the placement of interscalene brachial plexus catheters.

Major shoulder surgery can be extremely painful. Interscalene brachial plexus catheters provide excellent postoperative analgesia but are technically difficult to place. A new insulated Tuohy needle system for plexus catheterisation is now available. This prospective study examined its ease of use and the postoperative analgesia produced by patient-controlled interscalene analgesia with ropivacaine 0.2%. Nineteen patients undergoing major shoulder surgery were studied. Interscalene brachial plexus blocks were performed using a modified Winnie technique with the insulated Tuohy needle and a nerve stimulator. After injection of ropivacaine 0.75% 30-40 ml into the plexus, a catheter was inserted. Block and catheter insertion times were recorded. All 19 patients had successful blocks and had catheters successfully threaded. Catheter infusions provided successful analgesia (visual analogue pain score < 5/10) in 18 patients, with one failure, giving a 95% success rate. Mean [range] catheter insertion time was 3.6 [1-10] min. Decreased block and catheter insertion times were associated with experience with the equipment when comparing the mean (SD) times for the first seven catheters and the last seven catheters inserted (12.1 (4.2) min vs. 7.9 (2.4) min), p < 0.05). It is concluded that the insulated Tuohy needle system for interscalene catheterisation proved easy to use in the hands of someone who had not used it before, and can be recommended.

Evidence for an interaction between p-glycoprotein and cadmium toxicity in cadmium-resistant and -susceptible strains of Drosophila melanogaster.

The role of an ATP-dependent membrane protein, p-glycoprotein (pgp), in cadmium toxicity and resistance in Drosophila melanogaster was investigated. Two strains were compared, a wild-type and a cadmium-resistant strain. Verapamil (1, 10, and 100 mciroM) was added to the larval diet of Drosophila in both the presence and the absence of 80 ppm cadmium chloride. Adult emergence of wild-type but not of cadmium-resistant flies was reduced in the presence of cadmium. Verapamil in the larval diet without cadmium had no effect on adult emergence in either strain. Verapamil in the diet spiked with cadmium significantly reduced adult emergence in both strains. This result is indicative of an interaction between the efflux of cadmium and verapamil and demonstrates that pgps have a role in regulating the toxicity of cadmium in Drosophil. These results do not rule out pgps as putative cadmium resistance genes.

Postoperative analgesia following total knee arthroplasty: a study comparing spinal anesthesia and combined sciatic femoral 3-in-1 block.

BACKGROUND AND OBJECTIVES: The quality of analgesia and subsequent morphine requirements following spinal anesthetic block (SAB) or combined sciatic and femoral (3-in-1) block (SFB) for total knee arthroplasty were compared. METHODS: The 39 patients studied were randomly assigned to receive either SAB (n = 19) or SFB (n = 20). All patients received a standardized general anesthetic, patient-controlled analgesia, and regular diclofenac. Visual analog pain scores and morphine requirements were recorded for 48 hours following surgery. Observations were grouped into four 12-hour periods. Pain scores (0-10 cm) were expressed as 95% confidence intervals; the criterion for analgesic success was a confidence interval in the range 0-3 cm. RESULTS: Although pain-free on awakening, the SAB patients failed to achieve analgesic success in any of the four periods, while the SFB patients did so in three of the four periods. Morphine consumption was significantly higher in the SAB group during the first two periods but similar to the SFB group thereafter. CONCLUSION: In comparison with SAB, SFB resulted in superior analgesia and reduced morphine consumption for the first 24 hours following total knee arthroplasty.

Suppressive rod-cone interactions: evidence for separate retinal (temporal) and extraretinal (spatial) mechanisms in achromatic vision.

We investigated the influence of selective rod light and dark adaptation on cone-mediated sensitivity to monocular displays modulated sinusoidally in both spatial and temporal domains. Rod light adaptation (1) increased sensitivity to high spatial frequencies [> or = 8 cycles per degree (cpd)] flickered slowly (< or = 2 Hz), an effect that we refer to as grating suppressive rod-cone interaction (gSRCI); (2) increased sensitivity to low spatial frequencies (< or = 2 cpd) flickered rapidly (> or = 8 Hz), an effect that we refer to as flicker suppressive rod-cone interaction (fSRCI); and (3) had relatively little influence on intermediate temporal-spatial-frequency combinations. The magnitudes of both gSRCI and fSRCI increased as the retinal position of the test display was increasingly displaced parafoveally. In parafoveal retina, both forms of suppressive rod-cone interaction increased as the overall dimension of the test stimulus decreased. However, sensitivity to high spatial frequencies is equally well influenced by adaptation of the viewing and the contralateral eye, while the adapted state of the nonviewing eye negligibly influences sensitivity to rapid flicker. Moreover, gSRCI cannot be observed with a small (30-arcmin) grating restricted to the fovea, while fSRCI is a prominent effect with small foveal test stimuli. Collectively, these results and neurobiological evidence suggest that fSRCI reflects a mechanism restricted to distal retinal, while gSRCI involves extraretinal neural circuitry.

The laryngeal mask airway for thyroid and parathyroid surgery.

The rôle of the laryngeal mask airway for thyroid and parathyroid surgery was studied in 97 consecutive patients. In 50% the technique combined electrical stimulation of the recurrent laryngeal nerve with visualisation of vocal cord movement via a fibreoptic bronchoscope. Stimulation was required in 10% to assist in identifying recurrent laryngeal nerve position during difficult surgical dissection. In the remaining 40% stimulation was used to confirm nerve integrity and for teaching purposes. Tracheal intubation was required for seven patients but in only two of these was intubation unplanned. The incidence of postoperative recurrent laryngeal nerve dysfunction was zero. These data suggest that the technique offers a safe alternative in airway management and may provide advantages in terms of preservation of recurrent laryngeal nerve function.

Characteristics of veterans in Hawaii with and without diagnoses of post-traumatic stress disorder.

A total of 118 combat veterans seeking services at the VA Medical Center in Honolulu were assessed on a variety of demographic and psychometric dimensions, permitting the first systematic comparison on the measured variables between veterans with and without PTSD in the multicultural population of veterans in Hawaii. The results have implications for medical interventions with this population.

Relationship of cynical hostility and PTSD among Vietnam veterans.

The personality construct of cynical hostility, as measured by the Cook-Medley scale (an MMPI subscale), has been implicated as a risk factor for cardiovascular disease. A literature review suggests that Vietnam veterans exhibit many cynical hostility-like characteristics. We examined the association between Cook-Medley scores and PTSD among Vietnam and other-era veterans. Study 1 involved analyses of data from 1293 MMPIs administered at Department of Veterans Affairs in Honolulu between 1986-1991. Cook-Medley scores were highly correlated with MMPI PTSD scores, and Vietnam Era veterans obtained higher scores than veterans from other eras. In Study 2, twenty nine Vietnam veterans with PTSD disability ratings obtained very high Cook-Medley scores which were higher than Vietnam Era veterans without rated PTSD. Findings indicate that the cynical hostility literature has considerable relevance for study of PTSD and suggest that PTSD veterans may have heightened risk for developing cardiovascular disease. Several directions for future research are suggested.