Jonathan B. Koea
North Shore Hospital
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Featured researches published by Jonathan B. Koea.
Hpb Surgery | 2009
Jonathan B. Koea; Yatin Young; Kerry Gunn
Background. A comprehensive care package for patients undergoing hepatectomy was developed with the aim of minimal physiological disturbance in the peri-operative period. Peri-operative analgesia with few gastrointestinal effects and reduced requirement for intravenous (IV) fluid therapy was central to this plan. Methods. Data on 100 consecutive patients managed with continuous epidural infusion (n = 50; bupivicaine 0.125% and fentanyl 2 μg/mL at 0.1 mL/kg/hr) or intrathecal morphine (n = 50; 300 μg in combination with oral gabapentin 1200 mg preoperatively and 400 mg bd postoperatively) was compared. Results. The epidural and intrathecal morphine groups were equivalent in terms of patient demographics, procedures and complications. Patients receiving intrathecal morphine received less intra-operative IV fluids (median 1500 mL versus 2200 mL, P = .06), less postoperative IV fluids (median 1200 mL versus 4300 mL, P = .03) than patients receiving epidural infusion. Patients managed with intrathecal morphine established a normal dietary intake sooner (16 hours versus 20 hours, P = .05) and had shorter hospital stays than those managed with epidural infusions (4.7 ± 0.9 days versus 6.8 ± 1.2 days, P = .02). Conclusions. Single dose intrathecal morphine is a safe and effective means of providing peri-operative analgesia. Patients managed with intrathecal morphine have reduced peri-operative physiological disturbance and return home within a few days of hepatic resection.
Journal of Clinical Epidemiology | 2014
Diana Sarfati; Jason Gurney; James Stanley; Clare Salmond; Peter Crampton; Elizabeth Dennett; Jonathan B. Koea; Neil Pearce
OBJECTIVE We aimed to develop and validate administrative data-based comorbidity indices for a range of cancer types that included all relevant concomitant conditions. STUDY DESIGN AND SETTINGS Patients diagnosed with colorectal, breast, gynecological, upper gastrointestinal, or urological cancers identified from the National Cancer Registry between July 1, 2006 and June 30, 2008 for the development cohort (n=14,096) and July 1, 2008 to December 31, 2009 for the validation cohort (n=11,014) were identified. A total of 50 conditions were identified using hospital discharge data before cancer diagnosis. Five site-specific indices and a combined site index were developed, with conditions weighted according to their log hazard ratios from age- and stage-adjusted Cox regression models with noncancer death as the outcome. We compared the performance of these indices (the C3 indices) with the Charlson and National Cancer Institute (NCI) comorbidity indices. RESULTS The correlation between the Charlson and C3 index scores ranged between 0.61 and 0.78. The C3 index outperformed the Charlson and NCI indices for all sites combined, colorectal, and upper gastrointestinal cancer, performing similarly for urological, breast, and gynecological cancers. CONCLUSION The C3 indices provide a valid alternative to measuring comorbidity in cancer populations, in some cases providing a modest improvement over other indices.
Asia-pacific Journal of Clinical Oncology | 2016
Diana Sarfati; Jason Gurney; Bee Teng Lim; Nasser Bagheri; Andrew Simpson; Jonathan B. Koea; Elizabeth Dennett
Our study sought to optimize the identification and investigate the impact of comorbidity in cancer patients using routinely collected hospitalization data.
BMC Cancer | 2014
Diana Sarfati; Jason Gurney; James Stanley; Jonathan B. Koea
BackgroundComorbidity has an adverse impact on cancer survival partly through its negative impact on receipt of curative treatment. Comorbidity is unevenly distributed within populations, with some ethnic and socioeconomic groups having considerably higher burden. The aim of this study was to investigate the inter-relationships between comorbidity, ethnicity, receipt of treatment, and cancer survival among patients with stomach and liver cancer in New Zealand.MethodsUsing the New Zealand Cancer Registry, Māori patients diagnosed with stomach and liver cancers were identified (n = 269), and compared with a randomly selected group of non-Māori patients (n = 255). Clinical and outcome data were collected from medical records, and the administrative hospitalisation and mortality databases. Logistic and Cox regression modelling with multivariable adjustment were used to examine the impacts of ethnicity and comorbidity on receipt of treatment, and the impact of these variables on all-cause and cancer specific survival.ResultsMore than 70% of patients had died by two years post-diagnosis. As comorbidity burden increased among those with Stage I-III disease, the likelihood that the patient would receive curative surgery decreased (e.g. C3 Index score 6 vs 0, adjusted OR: 0.32, 95% CI 0.13-0.78) and risk of mortality increased (e.g. C3 Index score 6 vs 0, adjusted all-cause HR: 1.44, 95% CI 0.93-2.23). Receipt of curative surgery reduced this excess mortality, in some cases substantially; but the extent to which this occurred varied by level of comorbidity. Māori patients had somewhat higher levels of comorbidity (34% in highest comorbidity category compared with 23% for non-Māori) and poorer survival that was not explained by age, sex, site, stage, comorbidity or receipt of curative surgery (adjusted cancer-specific HR: 1.36, 95% CI 0.97-1.90; adjusted all-cause HR: 1.33, 95% CI 0.97-1.82). Access to healthcare factors accounted for 25-36% of this survival difference.ConclusionsPatients with comorbidity were substantially less likely to receive curative surgery and more likely to die than those without comorbidity. Receipt of curative surgery markedly reduced their excess mortality. Despite no discernible difference in likelihood of curative treatment receipt, Māori remained more likely to die than non-Māori even after adjusting for confounding and mediating variables.
Cancer Epidemiology | 2013
Jason Gurney; Diana Sarfati; James Stanley; Elizabeth Dennett; Carol Johnson; Jonathan B. Koea; Andrew Simpson; Rodney Studd
PURPOSE Information on cancer stage at diagnosis is critical for population studies investigating cancer care and outcomes. Few studies have examined the factors which impact (1) staging or (2) outcomes for patients who are registered as having unknown stage. This study investigated (1) the prevalence of unknown stage at diagnosis on the New Zealand Cancer Registry (NZCR); (2) explored factors which predict unknown stage; (3) described receipt of surgery and (4) survival outcomes for patients with unknown stage. METHODS Patients diagnosed with the most prevalent 18 cancers between 2006 and 2008 (N=41,489) were identified from the NZCR, with additional data obtained from mortality and hospitalisation databases. Logistic and Cox regression were used to investigate predictors of unknown stage and patient outcomes. RESULTS (1) Three distinct groups of cancers were found based on proportion of patients with unknown stage (low=up to 33% unknown stage; moderate=33-64%; high=65%+). (2) Increasing age was a significant predictor of unknown stage (adjusted odds ratios [ORs]: 1.18-1.24 per 5-year increase across groups). Patients with substantive comorbidity were more likely to have unknown stage but only for those cancers with a low (OR=2.65 [2.28-3.09]) or moderate (OR=1.17 [1.03-1.33]) proportion of patients with unknown stage. (3) Patients with unknown stage were significantly less likely to have received definitive surgery than those with local or regional disease across investigated cancers. (4) Patients with unknown stage had 28-day and 1-year survival which was intermediate between regional and distant disease. DISCUSSION We found that stage completeness differs widely by cancer site. In many cases, the proportion of unknown stage on a population-based register can be explained by patient, service and/or cancer related factors.
Anz Journal of Surgery | 2012
Jonathan B. Koea
Background: Hepatic hydatid disease is now rare in Australasia. However, it remains a significant problem in endemic areas. Many cases are now managed using minimally invasive techniques and this paper reviews the current status of laparoscopic approaches to hepatic hydatid disease.
Qualitative Health Research | 2015
Kevin Dew; Maria Stubbe; Louise Signal; Jeannine Stairmand; Elizabeth Dennett; Jonathan B. Koea; Andrew Simpson; Diana Sarfati; Chris Cunningham; Lesley Batten; Lis Ellison-Loschmann; Josh Barton; Maureen Holdaway
Little research has been undertaken on the actual decision-making processes in cancer care multidisciplinary meetings (MDMs). This article was based on a qualitative observational study of two regional cancer treatment centers in New Zealand. We audiorecorded 10 meetings in which 106 patient cases were discussed. Members of the meetings categorized cases in varying ways, drew on a range of sources of authority, expressed different value positions, and utilized a variety of strategies to justify their actions. An important dimension of authority was encountered authority—the authority a clinician has because of meeting the patient. The MDM chairperson can play an important role in making explicit the sources of authority being drawn on and the value positions of members to provide more clarity to the decision-making process. Attending to issues of process, authority, and values in MDMs has the potential to improve cancer care decision making and ultimately, health outcomes.
Hpb | 2013
Jonathan B. Koea
OBJECTIVES Hepatic incidentalomas (HI) are asymptomatic lesions detected incidentally during investigations for other pathologies. This prospective series outlines the management and outcomes of 121 HI managed over 7 years. METHODS Data were recorded prospectively on 121 patients referred between 2003 and 2010 for assessment of HI out of 1081 patients referred for a hepatic resection. Patients were reviewed in multidisciplinary meetings and investigated with tumour markers and radiological investigations. HI were classified as hypo- or hypervascular depending on arterial phase CT scan findings. Univariate and multivariate analysis was performed to define predictive factors for malignancy. RESULTS Forty HI were hypovascular, 35 were benign (18 cysts, 12 focal fatty sparing, 1 fetal lobulation and 4 solitary necrotic nodules) and 5 cholangiocarcinomas (all resected)]. Eighty-one HI were hypervascular, 72 were benign [40 focal nodular hyperplasia (FNH), 8 adenoma and 24 hemangiomas) and 9 cancers (5 HCC, 4 metastases: 7 resected). Male gender [relative risk (RR) 2.70, confidence interval (CI) 1.69-3.51], age >45 years (RR 3.15, CI 2.71-3.89), tumour diameter >4 cm (RR 3.35, CI 3.13-4.01) and late (8 min) enhancement on magnetic resonace imaging (MRI) (RR 4.15, CI 3.01-4.79) were predictive of malignancy. CONCLUSIONS HI constitute 10% of practice volume. 10% of hyper and hypovascular incidental lesions are malignant. Most can be treated aggressively after diagnosis.
Archive | 2001
Lincoln H. Israel; Jonathan B. Koea; Ian D. Stewart; Cheryl L. Wright; Paul D. Frankish
The phenomenon of strictures of the colon induced by nonsteroidal anti-inflammatory drugs is a newly recognized pathologic entity that has gained little exposure in the surgical literature to date. A further case is reported and the clinical features of this entity are discussed. Most patients present with symptoms suggestive of malignancy, namely anemia, obstructive symptoms, or weight loss. Pathologic changes are characterized by diaphragm-like strictures with submucosal fibrosis. Surgical resection to exclude malignancy and treat symptoms along with cessation of the nonsteroidal anti-inflammatory drug is the treatment of choice.
Hpb | 2015
Sanket Srinivasa; Wai G. Lee; Ali Aldameh; Jonathan B. Koea
BACKGROUND A spontaneous hepatic haemorrhage (SHH) is a rare condition that presents acutely to both hepatobiliary and general surgeons. Management of the condition is challenging because of the emergent presentation requiring immediate intervention, the presence of underlying chronic liver disease and the multiple potential underlying aetiological conditions. METHODS A literature search on a spontaneous hepatic haemorrhage was instituted on Medline (1966-2014), Cochrane Register of Controlled Trials, EMBASE (1947-2014), PubMed, Web of Science and Google Scholar. The specific topics of interest were causes - including rare causes, pathophysiological mechanisms and management options. A narrative review was planned from the outset. RESULTS After 1546 abstracts were reviewed, 74 studies were chosen for inclusion. Hepatocellular carcinoma (HCC) is the commonest cause of a spontaneous haemorrhage with 10% of HCC presenting with bleeding. Other causes are benign hepatic lesions (hemangioma, adenoma, focal nodular hyperplasia, nodular regenerative hyperplasia, biliary cystadenoma and angiomyelolipoma), malignant hepatic tumours (angiosarcoma, haemangioendothelioma, hepatoblastoma and rhabdoid sarcoma), peliosis hepatis, amyloid, systemic lupus erythematosis, polyarteritis nodosa, HELLP syndrome and acute fatty liver of pregnancy. Treatment practice emphasizes arterial embolization to obtain haemostasis with a hepatectomy reserved for tumour-bearing patients after staging and assessment of liver function. CONCLUSION A spontaneous hepatic haemorrhage is an acute presentation of a spectrum of conditions that requires early diagnosis and multidisciplinary management.