No weak days? Impact of day in the week on surgical mortality.

BACKGROUND: Studies show increased rates of mortality for admissions on the weekend (WE) versus the weekday (WD). However, scepticism exists of this so-called 'weekend effect' on patient outcome. It remains poorly investigated, particularly the timing of the day of surgery and post-operative outcomes. A UK study found higher odds of death when operated on Friday and the WE, versus WD. This relationship was investigated by interrogating the Australian and New Zealand Audit of Surgical Mortality database. METHODS: A standardized tool is used to collect data after every surgical death. Data in this retrospective cohort study from participating private and public hospitals in Australia on elective and emergency operations were extracted and included 7718 patients who had a surgical procedure within 30 days of admission and who subsequently died. A proxy measure of early surgical mortality, namely odds of dying within the first 48 h following surgery, was used to compare surgical mortality across days of the week. RESULTS: Unadjusted and adjusted odds of early surgical mortality were higher on the WE compared to WD, unadjusted and adjusted OR 1.30 (P < 0.001) and 1.19 (P = 0.026), respectively. When separated by day of week, there was a trend for higher surgical mortality on Friday, Saturday and Sunday versus all other days, although this did not reach statistical significance. ASA grade and specialty of surgery were important predictors of outcome. CONCLUSION: There appears to be an association between day of surgery and surgical outcome. The exact cause and contributing factors requires further investigation.

Australian and New Zealand Audit of Surgical Mortality: concordance between reported and audited clinical events and delays in management in surgical mortality patients.

BACKGROUND: The Australian and New Zealand Audit of Surgical Mortality (ANZASM) is a nationwide confidential peer review of deaths associated with surgical care. This study assesses the concordance between treating surgeons and peer reviewers in reporting clinical events and delays in management. METHODS: This is a retrospective cross-sectional analysis of deaths in 2009 and 2010. Cases that went through the process of submission of details by the surgeon in a structured surgical case form (SCF), first-line assessment (FLA) and a more detailed second-line assessment (SLA) were included. Significant clinical events reported for these patients were categorized and analysed for concordance. RESULTS: Of the 11,303 notifications of death to the ANZASM, 6507 (57.6%) were audited and 685 (10.5%) required the entire review process. Nationally, the most significant events were post-operative complications, poor preoperative assessment and delay to surgery or diagnosis. The SCF submissions reported 338 events, as compared with 1009 and 985 events reported through FLA and SLA, respectively (P = 0.01). Treating surgeons and assessors attributed 29-30% of events to factors outside the surgeon's control. Surgeons felt that delay to surgery or diagnosis was a significant event in 6.6% of cases, in contrast to 20% by assessors (P = 0.01). Preoperative management could be improved in 19% of cases according to surgeons, compared with 45 and 36% according to the assessors (P < 0.001). CONCLUSION: There is significant discordance between treating surgeons and assessors. This suggests the need for in-depth analysis and possible refinement of the audit process.

Bimodal electric tissue ablation (BETA) compared with the Cool-Tip RFA system.

BACKGROUND: Bimodal electric tissue ablation (BETA) incorporates the process of electrolysis into radiofrequency ablation (RFA) to increase the size of tissue ablation. This study investigated whether BETA could increase the efficacy of the Cool-Tip RF system (Covidien, Boulder, CO, USA) to produce larger ablations. It also investigated whether applying electrolysis only during the pretreatment phase (called electrochemical treatment (ECT)/RFA group) is as effective as BETA (where electrolysis was used during both the pretreatment and RFA phases). METHODS: A Cool-Tip RF system (Covidien) was used to test three types of ablations (RFA, BETA, and ECT/RFA) in a pig liver model. In BETA, 9 V of direct current was provided for 10 min, after which the RF generator was started and both electrical circuits were allowed to run concurrently. In ECT/RFA, however, the direct current circuit was switched off after 10 min of pretreatment and only RFA was performed as described above. Ablation sizes were measured in three dimensions. RESULTS: The size of ablations (transverse diameter A and B) produced by BETA and ECT/RFA was significantly larger compared with standard RFA (P < 0/001). BETA also created larger ablations compared with ECT/RFA (P < 0.001). CONCLUSION: BETA could improve the efficacy of the Cool-Tip RF system (Covidien) to achieve larger ablations. The increased tissue hydration improved delivery of electrical energy to the tissues and delayed the process of desiccation, thus allowing the ablation process to continue for longer periods of time to produce larger ablations. BETA could be used to treat larger liver tumours more effectively than standard RFA.

Bimodal electric tissue ablation (BETA): a study on ablation size when the anode is placed on the peritoneum and the liver.

BACKGROUND: In bimodal electric tissue ablation (BETA), the cathode of the DC circuit is attached to the radiofrequency (RF) electrode to increase the surrounding tissue hydration. This will delay tissue desiccation and allowing the ablation process to continue for a longer period of time before "roll-off" occurs, resulting in larger ablations compared with standard radiofrequency ablation (RFA). Previous research showed that attaching the anode to the skin using electrosurgical grounding pads would reduce the efficacy of BETA because of the high electrical resistivity of the skin. This study investigated the ablation size produced when the anode was attached to the peritoneum (BETA-peritoneum) and the liver (BETA-liver) respectively. MATERIALS AND METHODS: The anode of the DC circuit in BETA was attached to the peritoneum and the liver in a pig model using ECG dots. In BETA, 9 V of DC was provided for 10 min, after which the radiofrequency generator were switched on and both electrical circuits allowed to run concurrently until "roll-off." The size of ablations produced was compared to when the anode attached to the skin (BETA-skin) and standard RFA, respectively. The sites of anode placement were examined for local tissue injury. RESULTS: The transverse diameters in BETA-peritoneum and BETA-liver were significantly larger compared with BETA-skin and standard RFA, respectively (P < 0.001). The axial diameter in the BETA-peritoneum and BETA-liver groups were also larger compared with the BETA-skin and RFA groups, although the differences did not reach statistical significance (P = 0.09). Hematoxylin and eosin (H and E) examination of the peritoneum and the liver where the anode was attached showed coagulation necrosis involving the superficial epithelium and the liver capsule, respectively. CONCLUSIONS: BETA can be used to treat larger liver tumors more effectively and may reduce the tumor recurrence rates compared with standard RFA. The efficacy of BETA depends on ensuring good electrical conductivity between the cathode and the anode of the DC circuit. Research so far has shown that BETA works best when the anode is placed deep to the skin as the stratum corneum consisted of a layer of a-nucleated cells, which have high electrical resistivity. The liver could be the ideal location to place the anode as it has excellent electrical conductivity, therefore ensuring maximum tissue hydration around the cathode to produce the largest ablations possible.

Bimodal electric tissue ablation (BETA)--effect of reversing the polarity of the direct current on the size of ablation.

BACKGROUND: Bimodal electric tissue ablation (BETA) is a new technique that uses the direct current in electrolysis to improve the efficacy of radio frequency (RF) ablation. It was hypothesized that attaching the cathode of the electrolytic circuit to the RF electrode will increase the tissue hydration, therefore delaying tissue desiccation during ablation. Consequently, the ablation process can continue for a longer period of time and produce larger ablations. This hypothesis was tested by reversing the polarity of the electrolytic circuit, which theoretically would cause tissue desiccation and therefore produce smaller ablations. This new setup is called reversed polarity bimodal electric ablation (RP-BEA). MATERIALS AND METHODS: Three types of ablations standard radiofrequency ablation (RFA), BETA, and RP-BEA) were tested in a pig liver model. In BETA and RP-BEA, 9 V of direct current were provided for 10 min, after which the rf generator were switched on and both electrical circuits allowed to run concurrently. In all three setups, ablations were continued until "roll-off." The size of ablation was measured and compared with each other. RESULTS: The duration of ablation was significantly shorted in RP-BEA compared with standard RFA and BETA (48 s verus 148 s and 84 s, respectively, P = 0.004). The sizes of ablations in RP-BEA were also significantly smaller compared with standard RFA and BETA-skin. CONCLUSION: RP-BEA caused tissue desiccation resulting in a shorter duration of ablation and smaller ablations. Therefore, the theory that BETA increases ablation size due to the effects of increased tissue hydration around the rf electrode is correct.

A population-based study of thrombolysis for acute stroke in South Australia.

OBJECTIVE: To report the rate of thrombolysis for treating acute stroke in South Australia from October 2007 to September 2009. We hypothesised that the rate of thrombolytic therapy would be related to distance from an acute stroke unit. DESIGN, SETTING AND PATIENTS: An observational, population-based, retrospective review of case notes and imaging, using multiple case-ascertainment methods. Patients administered a thrombolytic agent by any method for suspected ischaemic stroke in urban, rural, public and private hospitals in SA (covering a population of 1.5 million people) were included. MAIN OUTCOME MEASURES: Absolute and relative contraindications for thrombolysis administration in each case, according to the 2007 National Stroke Foundation guidelines; incidence of haemorrhage; and population thrombolysis rates according to distance from an acute stroke unit. RESULTS: A total of 158 cases of thrombolytic therapy for suspected acute ischaemic stroke were identified in 157 patients. Fifteen patients (10%) had symptomatic intracranial haemorrhage, of whom eight (5%) died within 3 months. Seven patients had symptomatic extracranial haemorrhage. Five patients (3%) received thrombolysis despite absolute contraindications. Patients living closer to stroke units were more likely to receive thrombolysis. CONCLUSIONS: Rates of symptomatic haemorrhage after thrombolysis were similar to those in voluntary registries. A large proportion of South Australians are currently missing out on acute stroke therapy as a result of poor access to acute stroke units in both urban and rural settings. It is estimated that fewer than 2% of ischaemic stroke patients are administered thrombolysis in SA.

Morphometric evaluation of duodenal biopsies in celiac disease.

OBJECTIVES: The Marsh classification is a semiquantitative method for the diagnosis and monitoring of changes in duodenal biopsies in celiac disease. We have explored the possibility that quantitative changes in villous area and crypt length (morphometry) may provide better information on changes in duodenal morphology, particularly after the introduction of a gluten-free diet. METHODS: We measured villous height, apical and basal villous widths, and crypt length in 57 adults with celiac disease and 83 control subjects. Villous area was calculated as a trapezoid approximation. Serial changes in villous area and crypt length were determined at regular intervals for up to 4 years after the introduction of a gluten-free diet. Morphometric changes were also correlated with Marsh grade, self-reported adherence to a gluten-free diet, and changes in celiac serology. RESULTS: The gluten-free diet resulted in a progressive increase in villous area and a progressive decrease in crypt length. Morphometric improvement reached a plateau after 6-12 months with mean villous area attaining a value approximately half that of control subjects. Morphometric data were more sensitive than Marsh grade. Improvement in morphometric indices was significantly associated with the disappearance of anti-endomysial IgA antibody but not with dietary compliance. CONCLUSIONS: Morphometry is a sensitive way to document changes in duodenal biopsies in celiac disease. In adults treated with a gluten-free diet, it is uncommon for villous area to return to values observed in control subjects, but morphometric improvement is associated with the disappearance of anti-endomysial IgA antibody.

Effect of testosterone and a nutritional supplement, alone and in combination, on hospital admissions in undernourished older men and women.

BACKGROUND: In older people, undernutrition is associated with increased hospitalization rates and mortality. Because weight loss in older people often reflects a disproportionate reduction of skeletal muscle, anabolic treatments may be beneficial. OBJECTIVE: Our aim was to evaluate the hypothesis that testosterone treatment and a nutritional supplement have additive benefits. DESIGN: Oral testosterone undecanoate (40 mg daily for women, 80 mg twice daily for men) and an oral nutritional supplement (475 kcal/d) were administered, alone or combined, for 1 y to 49 community-dwelling, undernourished people [Mini Nutritional Assessment score <24 and low body weight (body mass index, in kg/m(2): <22) or recent weight loss (>7.5% over 3 mo)] aged >65 y (mean age: 77 y; 26 women and 23 men). Hospital admissions and other variables were assessed. RESULTS: In subjects receiving combined testosterone and nutritional supplements (n = 11), there were no hospital admissions, whereas there were 9 admissions (2 elective) in 13 subjects in the no-treatment group, 4 in the testosterone-treated group (n = 12), and 5 in the supplement-treated group (n = 13); P = 0.06 with no-treatment compared with combined treatment. When compared with the no-treatment group, the combined-treatment group had significantly fewer subjects admitted to hospital (0 compared with 5, P = 0.03), fewer days in hospital (0 compared with 74, P = 0.041), and a longer time to hospital admission (P = 0.017). CONCLUSIONS: In undernourished older people, combined treatment with testosterone and nutritional supplementation reduced the number of people hospitalized and the duration of hospital admissions, which are important endpoints in this group. Larger, confirmatory studies are now needed. This trial was registered before commencement at clinical trials.gov as NCT00117000.

Statins inhibit neutrophil infiltration in skeletal muscle reperfusion injury.

BACKGROUND: Neutrophil infiltration is a major determinant of ischemia-reperfusion injury (IRI). Statins improve endothelial function by elevating nitric oxide synthase activity and inhibiting adhesion molecule expression and may, therefore, inhibit IRI-induced neutrophil extravasation. Although statins are protective against myocardial IRI and stroke, a role for statins in ameliorating skeletal muscle IRI has not yet been confirmed. This study, therefore, addressed the hypothesis that simvastatin would attenuate the severity of tissue damage during skeletal muscle IRI. METHODS: Rats were administered simvastatin for 6 d before 4 h hind limb ischemia and 24 h reperfusion. Neutrophil infiltration was assessed using myeloperoxidase (MPO) assays and tissue damage by quantitative immunohistochemical analysis of collagen IV. The effect of reducing nitric oxide levels on the severity of IRI was assessed by administering the NOS inhibitor, N-Imino-L-ornithine (L-NIO), before ischemia. RESULTS: Simvastatin significantly inhibited IRI-induced MPO activity but not collagen degradation in postischemic skeletal muscle. Inhibition of nitric oxide synthase by L-NIO markedly inhibited neutrophil infiltration and protected against IRI-induced collagen degradation. When both simvastatin and L-NIO were administered before IRI, the IRI-induced elevation in MPO activity was completely inhibited. However, paradoxically, simvastatin counteracted the protective effect of L-NIO against IRI-induced collagen IV degradation. CONCLUSIONS: The inhibition by simvastatin of IRI-induced neutrophil infiltration in skeletal muscle suggests that statins may be a useful therapy to attenuate the severity of IRI but their precise mechanisms of action remains to be determined. Nitric oxide also plays a cytotoxic, rather than protective, role in mediating IRI in this model.