We examined the ability of different frequencies in sympathetic nerve activity (SNA) to induce oscillations in renal blood flow (RBF). In anesthetized rabbits the renal nerves were stimulated using modulated sine patterns (base frequency 5 Hz, 5-ms duration pulses) that varied in amplitude between 0 and 10 V at a frequency between 0.04 and 1.0 Hz. The strengths of the induced oscillations in RBF were calculated using spectral analysis. Although faster rhythms in simulated SNA >0.6 Hz contributed to the level of vascular tone, 95% of the power in the frequency response curve was below this frequency, indicating a low-pass filtering/integrating characteristic of the vasculature. Frequencies <0.6 Hz were associated with increasing ability to induce oscillations in RBF. The ability of an SNA rhythm at 0.6 Hz to induce a rhythm in RBF was 21 times less than that at 0.25 Hz. At 0.16 Hz there was a distinct peak in the frequency response curve, indicating the vasculature was more sensitive in this frequency band to sympathetic stimulation. Blockade of endogenous nitric oxide by N G-nitro-l-arginine methyl ester (l-NAME; 20 mg/kg) did not alter resting RBF levels nor was the low-pass filtering/integrating characteristic of the vasculature to nerve stimulation changed (i.e., the curve was not shifted left or right); however, there was a selective increase in the sensitivity to stimulation at 0.16 Hz, i.e., larger oscillations in RBF were evoked. These results indicate an ability of SNA to induce resonant oscillations in the renal vasculature and that there may be active and passive modulators of these responses. Naturally occurring oscillations in SNA <0.6 Hz are likely to contribute to the dynamic control of RBF, ensuring it responds rapidly and with high gain to the stimuli of daily life, while filtering out the faster oscillations ensures stable glomerular filtration.

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Background: Textbook Outcome (TO) is a novel composite measure of clinical outcomes that can be used to measure the quality of surgical outcomes. TOs for pancreatic surgery were published by the Dutch Pancreatic Cancer Group (DPCG) in 2020. The aim of this study was to explore how a medium volume hepatopancreaticobiliary unit could use TO to benchmark local outcomes following pancreatic surgery. Methods: Retrospective analysis of prospectively collected data from patients who underwent pancreaticoduodenectomy (PD) or distal pancreatectomy (DP) for all indications between March 2005 and February 2020 at Christchurch Hospital (CH). Analysis of TO items as defined by the DPCG was performed and compared to nationwide Dutch outcomes (2014-2017), including cumulative analysis using CuSum. Results: In total, 273 patients were included (median age 63 years; 51% female) of which 182 (67%) underwent PD and 91 (33%) underwent DP (median annual volume 12 PDs/6 DPs). Overall, 58% of patients undergoing PD and 74% of patients undergoing DP achieved TO, compared with 58% and 67%, P = 0.944 and P = 0.231, respectively, for the Netherlands (median annual volume 33 PDs/8 DPs per hospital). Conclusions: TO offers a useful quality measure to benchmark local outcomes following pancreatic surgery against an external nationwide analysis. The results show that as a medium volume centre performance was comparable to previously published Dutch results, which included high volume centres. Applying CuSum methodology to the TO metric allows a continuous measure of performance. This offers the potential to provide feedback for quality improvement strategies.

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Cutaneous melanoma is much less common among Maori than among New Zealand Europeans, but Maori have a greater Breslow depth and therefore have a worse prognosis. Increased awareness on behalf of these groups and health care practitioners should assist in ensuring early detection, thereby improving the overall outcome in Maori.

Acceptable outcomes have been achieved for patients undergoing pancreatic resection within a centre that meets the criteria proposed by the NZ National Standards for treatment of pancreatic cancer.

Background Data on interventions to reduce postoperative pancreatic fistula (POPF) following pancreatoduodenectomy (PD) are conflicting. The aim of this study was to assimilate data from RCTs. Methods MEDLINE and Embase databases were searched systematically for RCTs evaluating interventions to reduce all grades of POPF or clinically relevant (CR) POPF after PD. Meta-analysis was undertaken for interventions investigated in multiple studies. A post hoc analysis of negative RCTs assessed whether these had appropriate statistical power. Results Among 22 interventions (7512 patients, 55 studies), 12 were assessed by multiple studies, and subjected to meta-analysis. Of these, external pancreatic duct drainage was the only intervention associated with reduced rates of both CR-POPF (odds ratio (OR) 0.40, 95 per cent c.i. 0.20 to 0.80) and all-POPF (OR 0.42, 0.25 to 0.70). Ulinastatin was associated with reduced rates of CR-POPF (OR 0.24, 0.06 to 0.93). Invagination (versus duct-to-mucosa) pancreatojejunostomy was associated with reduced rates of all-POPF (OR 0.60, 0.40 to 0.90). Most negative RCTs were found to be underpowered, with post hoc power calculations indicating that interventions would need to reduce the POPF rate to 1 per cent or less in order to achieve 80 per cent power in 16 of 34 (all-POPF) and 19 of 25 (CR-POPF) studies respectively. Conclusion This meta-analysis supports a role for several interventions to reduce POPF after PD. RCTs in this field were often relatively small and underpowered, especially those evaluating CR-POPF.