Peritoneal Defence Mechanisms and Staphylococcus Aureus in Patients Treated with Continuous Ambulatory Peritoneal Dialysis (CAPD)

Peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients due to S. aureus is associated with an adverse clinical outcome, suggesting impaired clearance of this organism by the host. The ability of peritoneal macrophages (PMO) derived from CAPD patients to take up S. aureus and mount a respiratory burst was investigated. Whilst significant activity was observed in the absence of opsonin, both parameters of phagocytosis were augmented by addition of 20% pooled human serum (PHS), complement-depleted PHS, and fibronectin. When used as sole opsonin, fibronectin resulted in a dose-related increase in chemiluminescent response by both blood neutrophils and PMO.

The opsonic activity of dialysis effluent, as judged by neutrophil chemiluminescence, correlated with IgG and fibronectin content, but not with complement as assessed by C3 levels. The addition of urokinase to dialysate improved its opsonic properties whilst having no effect on the activity of PHS-20%; this would suggest that the formation of fibrin in dialysate, promoted by S. aureus, interferes with phagocytosis. This and the low IgG, complement and fibronectin levels in dialysate may explain in part the relatively poor clearance of this organism from the peritoneum.

Selected Growth Factors in Peritoneal Dialysis: Their Relationship to Markers of Inflammation, Dialysis Adequacy, Residual Renal Function, and Peritoneal Membrane Transport

Objectives

Markers of chronic inflammation, acute-phase reactants, and growth factors may be concomitantly involved in a number of pathologic processes in the general population and uremic patients. In addition, growth factors may influence peritoneal membrane transport characteristics. However, the association between plasma growth factors, markers of chronic inflammation, and peritoneal membrane transport remains largely unknown. The aim of this study was to evaluate the relationship between plasma levels of selected growth factors [basic fibroblast growth factor (bFGF), transforming growth factor β1 (TGFβ1), vascular endothelial growth factor (VEGF)] and markers of chronic inflammation [interleukin (IL)-6, C-reactive protein (CRP), and fibrinogen] in continuous ambulatory peritoneal dialysis (CAPD) patients. The potential link between the above substances and dialysis adequacy was also explored.

Design

Single-center, cross-sectional study.

Setting

Peritoneal Dialysis Unit, Medical Faculty, Jagiellonian University Hospital, Kraków, Poland.

Patients

32 stable end-stage renal disease patients (13 M, 19 F; mean age 53.6 ± 13.7 years) on CAPD for a median period of 19.5 months. Patients free from signs and symptoms of any inflammatory disease (including peritonitis) for at least 3 months were included into the study. All patients underwent measurements of dialysis dose [Kt/V, weekly creatinine clearance (wCCr)] and peritoneal solute transport using a standard peritoneal equilibration test (PET).

Methods

TGFβ1, bFGF, VEGF, and IL-6 were measured with ELISA, CRP was assayed with immunonephelometry, and fibrinogen with Multifibren U reagent (Dade Behring Marburg GmbH, Marburg, Germany). Nephron 97 for Windows software was used to assess dialysis adequacy.

Results

Significant positive correlations between plasma bFGF and IL-6, as well as fibrinogen concentrations ( R = 0.36, p < 0.05 and R = 0.39, p < 0.05, respectively), were found. VEGF correlated significantly with IL-6 and CRP ( R = 0.65, p < 0.0001 and R = 0.51, p < 0.005, respectively). An association between VEGF and bFGF was also found ( R = 0.59, p < 0.0005). Serum level of TGFβ1 revealed no relationship with any marker of acute-phase activation, remaining growth factors, or dialysis adequacy. Positive correlation between TGFβ1 concentration and dialysate-to-plasma ratio for creatinine in PET ( R = 0.35, p < 0.05) was found. In addition, patients with lower solute transport (low/low-average transporters) had lower serum levels of both bFGF and TGFβ1 compared to patients with higher solute transport. Patients with total wCCr > 60 L/week/m2 were characterized by lower levels of bFGF and IL-6. Serum level of IL-6 and plasma levels of bFGF and VEGF were significantly lower among subjects with residual renal function (RRF) > 2.0 mL/minute.

Conclusions

Our results indicate that systemic inflammation in peritoneal dialysis patients is associated with increased plasma VEGF and bFGF but not TGFβ1. The negative correlation with RRF suggests that either the renal clearance of these cytokines and growth factors may contribute to their elimination, or cytokines and growth factors have a negative impact on RRF. We also suggest an association between serum levels of growth factors tested and peritoneal membrane function.

The Predictive Value of Kt/V and Peritoneal Solute Transport in Capd Patients is Dependent on the Type of Comorbidity Present

Comorbidity, age, dialysis dose (KT/Vurea)’ plasma albumin, and peritoneal function (DIP treat) were measured cross-sectionally in 228 continuous ambulatory peritoneal dialysis (CAPD) patients, who were then followed up for a mean of two years. Comorbidity, utilizing a semiquantitative score described previously, was the most powerful predictor of mortality in both univariate and multivariate analysis. Using univariate analysis, all the variables predicted outcome with statistical significance, mortality being associated with lower KT/V and plasma albumin and a higher DIP treat On multivariate analysis only comorbidity, age, and KT/V remained independent predictors.

Data was further analyzed on the basis of type of comorbid condition. In those patients without comorbid disease (n = 127) neither KT/V, albumin nor DIP retreamendicted outcome. In patients with clinical evidence of ischemic heart disease the KT/V was a significant predictor of favorable outcome. In those with clinical evidence of left ventricular function, mortality was significantly and independently associated with low plasma albumin, high DIP treat’ and KT/V. It is suggested that the concept of treatment adequacy in CAPD patients must include both measures of dialysis dose and peritoneal function, particularly in the context of the patient's comorbidity.

Fibronectin and Fibrinogen in the Plasma and Dialysate of Patients on CAPD

Plasma and dialysate fluid from 18 patients treated with continuous ambulatory peritoneal dialysis (CAPD) while peritonitis -free, were analysed for fibronectin (FN), fibrinogen (FG), albumin (ALB) and total protein (TP). Mean plasma FG (6.24 g/l) was higher than for normal controls (4.23 g/1; p < 0.001) whereas FN (0.31 g/l) was lower than for normal (0.36 g/l; p < 0.02). Twenty-four hour losses of proteins into the dialysate were as follows: TP = 10.9 g, ALB = 5.2 g, FN = 15.6 mg and FG = 221 mg. Mean dialysate concentration for FN was 2.09 mg/1 and FG 31.1 mg/l. Dialysate FN and FG correlated with dialysate ALB (r = 0.92; p < 0.001, r = 0.60; p < 0.01 respectively) suggesting an ultrafiltrate rather than synthesis within the peritoneum.

Relationship of Demographic, Dietary, and Clinical Factors to the Hydration Status of Patients on Peritoneal Dialysis

Objectives

To establish which clinical factors are associated with an increased proportion of extracellular fluid (ECF) in peritoneal dialysis (PD) patients.

Design

A single-center, cross-sectional analysis of 68 stable PD patients.

Method

Bioelectrical impedance measurements (RJL, single frequency; RJL Systems, Clinton, Michigan, USA) of resistance and reactance were used to determine the proportion of ECF comprising total body water (TBW) in 68 stable PD patients attending for routine clearance and membrane studies. All patients underwent detailed dietetic, adequacy, and membrane function tests. Blood pressure and antihypertensive requirements were also documented.

Results

Significant gender differences in body composition were observed, such that women had lower absolute TBW and fat-free mass per kilogram body weight, but proportionately more ECF for a given TBW, mean ECF:TBW 0.5 ± 0.03 versus 0.44 ± 0.05, p < 0.005. In view of this, patients were split into two groups, defined as “over-” or “normally” hydrated, either by using the single discriminator (median ECF:TBW = 0.47) for the whole population, which resulted in groups distorted by gender, or by using different discriminators according to gender (women: 0.49, men 0.45). In both analyses, overhydrated patients were older, had significantly lower plasma albumin, less total fluid removal per kilogram body weight, and higher peritoneal solute transport. When split by a single discriminator, the overhydrated patients had lower sodium removal and significantly less intracellular fluid volume due to an excess of women in this group who also had less residual function and had been on dialysis longer. Using gender-specific discrimination, overhydrated patients were heavier due to expansion of the ECF volume: 20 ± 4.1 L versus 16 ± 3.3 L, p < 0.001. Stepwise multivariate analysis found age ( p = 0.001), albumin ( p = 0.009), and fluid losses per kilogram body weight ( p = 0.025) to be independent predictors of gender-adjusted hydration status. Sodium intake did not vary according to hydration status.

Conclusion

Gender influences the assessment of hydration status of PD patients when employing bioimpedance, such that women tend to have more ECF. Taking this into account, age, albumin, and achieved fluid removal appear to be independently associated with hydration status, whereas peritoneal solute transport is not. Advice on dietary sodium should take account of hydration status and achievable losses.

Impact of Peritoneal Membrane Function on Long Term Clinical Outcome in Peritoneal Dialysis Patients

It is increasingly clear that peritoneal membrane transport status has clinical implications. The role of the peritoneum in dialysis delivery becomes para mount once residual renal function is lost, particularly as the membrane characteristics may change for the worse with time on treatment. These findings have several important implications:

Clinicians need to take solute transport character istics into account as they assess their patients.

Adverse effects of high solute transport include reduced ultrafiltration, solute removal (in particular, sodium), and increased peritoneal protein losses.

A need exists to replace lost residual renal function, not just with enhanced solute removal, but also with adequate salt and water removal.

The interpretation of urea and creatinine clear ances in anuric PD patients needs further consideration and validation.

Hypoalbuminemia in PD patients will result from the combined effects of high protein losses, over hydration, comorbidity, and malnutrition.

Adequacy Targets Can be Met in Anuric Patients by Automated Peritoneal Dialysis: Baseline Data from Eapos

♦ Objective

Conventional continuous ambulatory peritoneal dialysis (CAPD) in patients without residual renal function and with high solute transport is associated with worse clinical outcomes. Automated peritoneal dialysis (APD) has the potential to improve both solute clearance and ultrafiltration in these circumstances, but its efficacy as a treatment modality is unknown. The European Automated Peritoneal Dialysis Outcomes Study (EAPOS) is a 2-year, prospective, European multi-center study designed to determine APD feasibility and clinical outcomes in anuric patients. The present article describes the baseline data for patients recruited into the study.

♦ Design

All PD patients treated in the participating centers were screened for inclusion criteria [urinary output < 100 mL/24 h, or residual renal function (RRF) < 1 mL/min, or both]. After enrollment, changes were made to the dialysis prescription to achieve a weekly creatinine clearance above 60 L per 1.73 m2 and an ultrafiltration rate above 750 mL in 24 hours.

♦ Setting

The study is being conducted in 26 dialysis centers in 13 European countries.

♦ Baseline Data Collection

The information collected includes patient demographics, dialysis prescription, achieved weekly creatinine clearance, and 24-hour ultra-filtration (UF).

♦ Results

The study enrolled 177 anuric patients. Median dialysis duration before enrollment was 22.5 months (range: 0 – 285 months). Mean solute transport measured as the dialysate-to-plasma ratio of creatinine (D/PCr) was 0.74 ± 0.12. Patients received APD for a median of 9.0 hours overnight (range: 7 – 12 hours) using a median of 11.0 L of fluid (range: 6 – 28.75 L). Median daytime volume was 4.0 L (range: 0.0 – 9.0 L). Tidal dialysis was used in 26 patients, and icodextrin in 86 patients. At baseline, before treatment optimization, the weekly mean total creatinine clearance was 65.2 ± 14.4 L/1.73 m2, with 105 patients (60%) achieving the target of more than 60 L/1.73 m2. At baseline, 81% of patients with high transport, 69% with high-average transport, and 40% with low-average transport met the target. At baseline, 70% of patients with a body surface area (BSA) below 1.7 m2, 60% with a BSA of 1.7 – 2.0 m2, and 56% with a BSA above 2.0 m2 achieved 60 L/1.73 m2 weekly. Median UF was 1090 mL/24 h, and 75% of patients achieved the UF target of more than 750 mL/24 h.

♦ Conclusion

This baseline analysis of anuric patients recruited into the EAPOS study demonstrates that a high proportion of anuric patients on APD can achieve dialysis and ultrafiltration targets using a variety of regimes. This 2-year follow-up study aims to optimize APD prescription to reach predefined clearance and ultrafiltration targets, and to observe the resulting clinical outcomes.

Peritoneal Dialysis in the Patient with a Failing Renal Allograft

Background

Patients returning to dialysis treatment after a period with a functioning allograft represent a special case in the integrated care model of renal replacement therapy. They are known to nephrologists— and thus are ideal candidates for a timely commencement of dialysis—but they have had time to accrue additional cardiovascular risk. Furthermore, they have been exposed to prolonged immunosuppression.

Purpose

The present study aimed to establish the clinical outcomes of patients returning to peritoneal dialysis (PD) with failing allografts [survival, technique survival, longitudinal residual renal function (Kt/VR), peritoneal membrane function (solute transport), and plasma albumin] and to compare those outcomes with outcomes in new, contemporary patients.

Setting

The study was conducted in a single center where prospective collection of data now known to be important in determining outcome on peritoneal dialysis (age, comorbidity, albumin, Kt/VR, and solute transport) has been performed since 1989.

Methods

All patients commencing PD between 1989 and 2001 after failure of an allograft that had functioned for more than 6 months were identified. Outcomes in that group were compared to outcomes in all new PD patients and in all dialysis patients with failed grafts who were returning to hemodialysis (HD) in the same period.

Results

The study identified 45 patients with failed allografts: 28 were commencing PD treatment, and 17 were commencing HD treatment. Those patients were significantly younger than the 469 new patients commencing PD [FailedTx→ PD 41.2 years, FailedTx→ HD 38.9 years, NewPD 54.7 years; analysis of variance (ANOVA): p < 0.001]. We saw no significant difference in the survival of failed transplant patients commencing PD as compared with those commencing HD (log rank: p = 0.11). Kaplan–Meier plots of patient survival were better for failed transplant patients as compared with all new PD patients. When corrected using Cox regression, the survival advantage was seen to be due to age and comorbidity at start of PD. Pure technique failure (excluding death) was not different between the groups. Compared with all new PD patients, patients with failed allografts had similar longitudinal plasma albumin and a tendency toward an earlier increase in solute transport, but a more rapid loss of Kt/VR, ( p < 0.05 at 6 – 48 months).

Conclusions

Peritoneal dialysis would appear to be a good option for patients with failing allografts. Co-morbidity is the predominant determinant of survival. That finding underlines the need for attention to factors that might prevent accrual of cardiovascular risk during the post-transplantation period. The earlier loss of Kt/VR in those patients might be prevented by developing strategies of continued immunosuppression after commencement of dialysis, although infection risk is an important issue.

What is the Link between Poor Ultrafiltration and Increased Mortality in Anuric Patients on Automated Peritoneal Dialysis? Analysis of Data from Eapos

Background

Primary analysis of the European Automated Peritoneal Dialysis Outcomes Study (EAPOS) found that patients with daily ultrafiltration (UF) below a predefined target of 750 mL at baseline experienced increased mortality and continuing low UF over 2 years.

Setting

Multicenter, prospective observational study of prevalent, functionally anuric patients on automated peritoneal dialysis (APD) treated to predefined standards.

Methods

Secondary data analysis to determine clinical covariates that might support a link between poor UF and outcome, including pattern of comorbidity, prescription, nutrition as determined by Subjective Global Assessment (SGA), membrane function, and blood pressure (BP). Ultrafiltration was treated as a categorical (comparing patients above and below target at baseline) and continuous dependent variable in univariate and multivariate regression. The relationship between BP and survival was also explored.

Results

Of 177 patients recruited from 28 centers across Europe, 43 were below the UF target at baseline. Compared to those above target, there were no differences in the spread of comorbidity, type of APD prescription, SGA, BP, hemoglobin, HCO3, or parathyroid hormone, at baseline or at any later time. At baseline, plasma calcium and, at 12 months, plasma phosphate were lower in the low UF group. There was a weak positive correlation between baseline systolic or diastolic BP and UF, which remained on multivariate analysis but accounted for just 9% of the variability in BP. There was no clear relationship between baseline BP and survival, although, if anything, low BP was associated with earlier death. Poor UF was associated with lower mean dialysate glucose concentration during the first 4 months and with consistently worse membrane function.

Conclusions

The increased mortality associated with poor UF is likely multifactorial and not easily explained by clear differences in comorbidity, nutritional state, or other indices of treatment at baseline. The lower plasma phosphate suggests a subsequent fall in appetite. Poor BP control is unlikely to be the explanation, and a link between lower BP, reduced UF, and earlier death is suggested. Failure to achieve adequate UF due to worse membrane function remains an important and potentially reversible or preventable cause.

Supportive care for end-stage kidney disease: an integral part of kidney services across a range of income settings around the world

A key component of treatment for all people with advanced kidney disease is supportive care, which aims to improve quality of life and can be provided alongside therapies intended to prolong life, such as dialysis. This article addresses the key considerations of supportive care as part of integrated end-stage kidney disease care, with particular attention paid to programs in low- and middle-income countries. Supportive care should be an integrated component of care for patients with advanced chronic kidney disease, patients receiving kidney replacement therapy (KRT), and patients receiving non-KRT conservative care. Five themes are identified: improving information on prognosis and support, developing context-specific evidence, establishing appropriate metrics for monitoring care, clearly communicating the role of supportive care, and integrating supportive care into existing health care infrastructures. This report explores some general aspects of these 5 domains, before exploring their consequences in 4 health care situations/settings: in people approaching end-stage kidney disease in high-income countries and in low- and middle-income countries, and in people discontinuing KRT in high-income countries and in low- and middle-income countries.

The role of kidney transplantation as a component of integrated care for chronic kidney disease

Kidney transplant provides superior outcomes to dialysis as a treatment for end-stage kidney disease. Therefore, it is essential that kidney transplantation be part of an integrated treatment and management plan for chronic kidney disease (CKD). Developing an effective national program of transplantation is challenging because of the requirement for kidney donors and the need for a multidisciplinary team to provide expert care for both donors and recipients. This article outlines the steps necessary to establish a national kidney transplant program, starting with the requirement for effective legislation that provides the legal framework for transplantation whilst protecting organ donors, their families, recipients, and staff and is an essential requirement to combat organ trafficking. The next steps involve capacity building with the development of a multiskilled workforce, the credentialing of transplant centers, and the reporting of outcomes through national or regional registries. Although it is accepted that most transplant programs will begin with living related kidney donation, it is essential to aspire to and develop a deceased donor program. This requires engagement with multiple stakeholders, especially the patients, the general community, intensivists, and health departments. Development of transplant centers should be undertaken in concert with the development of a dialysis program. Both are essential components of integrated care for CKD and both should be viewed as part of the World Health Organization's initiative for universal health coverage. Provisions to cover the costs of treatment for patients need to be developed taking into account the state of development of the overall health framework in each country.

Accuracy of the estimation of V and the implications this has when applying Kt/Vurea for measuring dialysis dose in peritoneal dialysis

Background:

Current guidelines for the prescription of peritoneal dialysis dose rely on a single cut-off ‘minimal’ value of K t/ V. To apply this in the clinic, this requires an accurate estimation of V, the volume of urea distribution that equates to the total body water (TBW). This analysis sought to determine the accuracy to which V can be estimated.

Methods:

A literature search was undertaken of studies comparing TBW estimation using two or three of the following methods: isotopic dilution (gold standard), anthropometric equations (e.g. Watson formula) and bioimpedance analysis. Studies of healthy and dialysis populations of all ages were included. Mean differences and 95% limits of agreement (LOA) were extracted and pooled.

Results:

In 44 studies (31 including dialysis subjects), the between-method population means were typically within 1–1.5 L of each other, although larger bias was seen when applying anthropometric equations to different racial groups. However, the 95% LOA for all comparisons were consistently wide, typically ranging ±12–18% of the TBW. For a typical individual whose TBW is 35 L with a measured K t/ V of 1.7, this translates into a range of K t/ V 1.4–2.05.

Conclusions:

There are limitations to the accuracy of estimation of V which call into question the validity of applying a single threshold K t/ V value as indicative of adequate dialysis. This should be taken into account in guideline development such that if a target K t/ V was deemed appropriate that this should be expressed as a range; alternatively single targets should be avoided and dialysis dose should be determined according to patient need.

Incremental peritoneal dialysis

Incremental peritoneal dialysis (PD) has been variably defined. It involves taking advantage of the residual renal function that is usually present at initiation of dialysis to initially prescribe less onerous lower doses of PD while still achieving individualized clearance goals. We propose that incremental PD be defined as a strategy, rather than a particular regime, in which: (1) less than standard “full-dose” PD is initially prescribed in recognition of the value of residual renal function; (2) peritoneal clearance is initially less than the individualized clearance goal but the combination of peritoneal plus renal clearance achieves or exceeds that goal clearance; and (3) there is a clear intention to increase dose of PD as renal clearance declines and/or symptoms appear.

Incremental PD by its nature lessens the workload of dialysis for those doing PD, reduces cost and exposure of the peritoneal membrane to glucose, and may lessen mechanical symptoms. Evidence that incremental PD improves clinical outcomes compared to the use of full-dose PD is lacking but one randomized controlled trial, multiple observational studies, and a systematic review all suggest that outcomes are at least as good. Given that incremental PD costs less and is inherently less onerous, it is reasonable, pending larger randomized trials, to adopt this strategy.

Illness Perception Mediates the Relationship Between the Severity of Symptoms and Perceived Health Status in Patients With Behçet Disease

OBJECTIVE

The aim of this study was to investigate the relationship between psychological representations of illness, perceived health status, and self-assessment of symptom severity in patients with Behçet disease, a rare long-term incurable condition with unclear etiology.

METHODS

Using cross-sectional survey design, data on self-administered questionnaires on illness perception, health status, symptoms severity, and demographic characteristics were collected from 273 patients with Behçet disease (age range, 18-65 years). The data were subjected to mediation analysis to test whether cognitive and emotional components of illness perception mediate the relationship between the severity of symptoms and heath status.

RESULTS

The results support our hypotheses that cognitive components of illness perception (perceived consequences and identity of the illness) mediate the link between symptom activity and pain, whereas emotional components of the illness (emotional representations about the illness) mediate the relationship between disease activity and perceived energy level.

CONCLUSIONS

The robustness of these mediation effects suggests potential directions for clinical psychologists and health care practitioners in developing support programs. We supplement our study with Open Access database containing information about type of medication, comorbid mood disorder, and detailed measurement of the severity of BD symptoms for sharing and accumulating multidisciplinary knowledge aiming to support the development of interventions. Addressing psychological aspects of BD will help to manage complex patients effectively.

International Anemia Prevalence and Management in Peritoneal Dialysis Patients

Background:The optimal treatment for managing anemia in peritoneal dialysis (PD) patients and best clinical practices are not completely understood. We sought to characterize international variations in anemia measures and management among PD patients.Methods:The Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) enrolled adult PD patients from 6 countries from 2014 to 2017. Hemoglobin (Hb), ferritin levels, and transferrin saturation (TSAT), as well as erythropoiesis stimulating agents (ESAs) and iron use were compared cross-sectionally at study enrollment in Australia and New Zealand (A/NZ), Canada, Japan, the United Kingdom (UK), and the United States (US).Results:Among 3,603 PD patients from 193 facilities, mean Hb ranged from 11.0 - 11.3 g/dL across countries. The majority of patients (range 53% - 59%) had Hb 10 - 11.9 g/dL, with 4% - 12% patients ≥ 13 g/dL and 16% - 23% < 10 g/dL. Use of ESAs was higher in Japan (94% of patients) than elsewhere (66% - 79% of patients). In the US, 63% of patients had a ferritin level > 500 ng/mL, compared with 5% - 38% in other countries. In the US and Japan, 87% - 89% of PD patients had TSAT ≥ 20%, compared with 73% - 76% in other countries. Intravenous (IV) iron use within 4 months of enrollment was higher in the US (55% of patients) than elsewhere (6% - 17% patients).Conclusions:In this largest international observational study of anemia and anemia management in patients receiving PD, comparable Hb levels across countries were observed but with notable differences in ESA and iron use. Peritoneal dialysis patients in the US have higher ferritin levels and higher IV iron use than other countries.

A randomised trial of non-invasive cardiac output monitoring to guide haemodynamic optimisation in high risk patients undergoing urgent surgical repair of proximal femoral fractures (ClearNOF trial NCT02382185)

Background

Hip fracture is a procedure with high mortality and complication rates, and there exists a group especially at risk of these outcomes identified by their Nottingham Hip Fracture Score (NHFS). Meta-analysis suggests a possible benefit to this patient group from intravascular volume optimisation. We investigated whether intraoperative fluid and blood pressure optimisation improved complications in this group.

Methods

Patients with a NHFS ≥ 5 were enrolled into this multicentre observer-blinded randomised control trial. Patients were allocated to either standard care or a combination of fluid optimisation and blood pressure control using a non-invasive system. The primary outcome was the number of patients with one or more complications in each group. Secondary outcomes included hospital length of stay (LOS), incidence of hypotension and fluid and vasopressor usage.

Results

Forty-six percent of patients in the intervention group suffered one or more complications compared to the 51% in the control group (OR 0.82 (95% CI 0.49–1.36)). Per-protocol analysis improved the OR to 0.73 (95% CI 0.43–1.24). Median LOS was the same between both groups; however, the mean LOS on a per-protocol analysis was longer in the control group compared to the intervention group (23.2 (18.0) days vs. 18.5 (16.5), p = 0.047).

Conclusions

Haemodynamic optimisation including blood pressure management in high-risk patients undergoing repair of a hip fracture did not result in a statistically significant reduction in complications; however, a potential reduction in length of stay was seen.

Trial registration

A randomised trial of non-invasive cardiac output monitoring to guide haemodynamic optimisation in high risk patients undergoing urgent surgical repair of proximal femoral fractures (ClearNOF trial NCT02382185).

Ventilatory inefficiency adversely affects outcomes and longer-term survival after planned colorectal cancer surgery

BACKGROUND

Impaired cardiorespiratory reserve is an accepted risk factor for patients having major surgery. Ventilatory inefficiency, defined by an elevated ratio of minute ventilation to carbon dioxide excretion (VE/VCO₂), and measured by cardiopulmonary exercise testing (CPET), is a pathophysiological characteristic of patients with cardiorespiratory disease. We set out to evaluate the prevalence of ventilatory inefficiency in a colorectal cancer surgical population, and its influence on surgical outcomes and long-term cancer survival.

METHODS

In this retrospective study of 1375 patients who had undergone preoperative CPET followed by colorectal cancer surgery, we used receiver operating characteristic curve analysis to identify an optimal value of VE/VCO₂ associated with 90-day mortality. Binary logistic regression was used to evaluate whether this degree of ventilatory inefficiency was independently associated with decreased survival, both after surgery and in the longer term.

RESULTS

We identified an optimal VE/VCO₂ >39 cut-off for predicting 90-day mortality; 245 patients (17.8%) had VE/VCO₂ >39, of which 138 (10% of total cohort) had no known cardiorespiratory risk factors. Ventilatory inefficiency was independently associated with death at 90-days (8.2% mortality vs 1.9%; adjusted odds ratio [OR], 4.04; 95% confidence interval [CI], 2.09-7.84), with death after unplanned critical care admission (OR=4.45; 95% CI, 1.37-14.46) and with decreased survival at 2 yr (OR=2.21; 95%, 1.49-3.28) and 5 yr (OR=2.87; 95% CI, 1.54-5.37) after surgery.

CONCLUSIONS

A significant proportion of patients having colorectal cancer surgery have ventilatory inefficiency observed on CPET, the majority of whom have no history of cardiorespiratory risk factors. This group of patients has significantly decreased survival both after surgery and in the long-term, irrespective of cancer stage. Survival might be improved by formal medical evaluation and intervention in this group.