Decreased O2 consumption by PMNL from humans and rats with CRF: Role of secondary hyperparathyroidism

Decreased O2 consumption by PMNL from humans and rats with CRF: Role of secondary hyperparathyroidism. Bactericidal ability of polymorphonuclear leukocytes (PMNL) is impaired in chronic renal failure (CRF). This function of PMNL is mediated by the generation of oxidizing radicals and the latter event requires O2 consumption by these cells. The present study examined both basal and FMLP-stimulated rise in cytosolic calcium ([Ca2+]i) and O2 consumption of PMNL from normal subjects and hemodialysis patients and from CRF rats, and evaluated the potential role of secondary hyperparathyroidism of CRF on these properties of PMNL. Basal levels of [Ca2+]i were significantly higher, and FMLP-induced increments in [Ca2+]i were significantly lower in PMNL of both humans and rats with CRF than in normals. Basal and FMLP-stimulated O2 consumption were significantly lower in CRF subjects and rats than in normals. These derangements were prevented by prior parathyroidectomy of CRF rats or by their treatment with verapamil from day one of CRF. Also, therapy of rats with pre-existing CRF with this drug reversed the abnormalities in [Ca2+]i and in O2 consumption of PMNL. The data indicate that: (1) CRF is associated with derangements in the homeostasis of [Ca2+]i of PMNL and their oxygen consumption, (2) these abnormalities are, most likely, mediated by the state of secondary hyperparathyroidism of CRF, and (3) verapamil, which blocks the PTH-induced entry of calcium into cells, and prevents as well as reverses these PMNL dysfunctions. These results implicate the excess PTH of CRF in the genesis of the defective bactericidal function of PMNL, and assign a new dimension to PTH toxicity in CRF

The role of Goal Directed Therapy in the prevention of Acute Kidney Injury after Major Gastrointestinal Surgery: Sub-study of the OPTIMISE Trial

BACKGROUND: Acute kidney injury (AKI) is an important adverse outcome after major surgery. Peri-operative goal-directed haemodynamic therapy (GDT) may improve outcomes by reducing complications such as AKI. OBJECTIVE: To determine if GDT was associated with a reduced incidence of postoperative AKI according to specific renal biomarkers. DESIGN: Prospective substudy of the OPTIMISE trial, a multicentre randomised controlled trial comparing peri-operative GDT to usual patient care. SETTING: Four UK National Health Service hospitals. PATIENTS: A total of 287 high-risk patients aged at least 50 years undergoing major gastrointestinal surgery. OUTCOME MEASURES: The primary outcome measure was AKI defined as urinary neutrophil gelatinase-associated lipase (NGAL) at least 150 ng ml 24 and 72 h after surgery. Secondary outcomes were between-group differences in NGAL measurements and NGAL : creatinine ratios 24 and 72 h after surgery and AKI stage 2 or greater according to Kidney Disease Improving Global Outcomes (KDIGO) criteria within 30 days of surgery. RESULTS: In total, 20 of 287 patients (7%) experienced postoperative AKI of KDIGO grade 2 or 3 within 30 days. The proportion of patients with urinary NGAL at least 150 ng ml 24 or 72 h after surgery was similar in the two groups [GDT 31/144 (21.5%) patients vs. usual patient care 28/143 (19.6%) patients; P = 0.88]. Absolute values of urinary NGAL were also similar at 24 h (GDT 53.5 vs. usual patient care 44.1 ng ml; P = 0.38) and 72 h (GDT 45.1 vs. usual patient care 41.1 ng ml; P = 0.50) as were urinary NGAL : creatinine ratios at 24 h (GDT 45 vs. usual patient care 43 ng mg; P = 0.63) and 72 h (GDT 66 vs. usual patient care 63 ng mg; P = 0.62). The incidence of KDIGO-defined AKI was also similar between the groups [GDT 9/144 (6%) patients vs. usual patient care 11/143 (8%) patients; P = 0.80]. CONCLUSION: In this trial, GDT did not reduce the incidence of AKI amongst high-risk patients undergoing major gastrointestinal surgery. This may reflect improving standards in usual patient care. TRIAL REGISTRATION: OPTIMISE Trial Registration ISRCTN04386758

Can a renal nurse assess fluid status using ultrasound on the inferior vena cava? A cross-sectional interrater study

Introduction: Ultrasound of the inferior vena cava (IVC-US) has been used to estimate intravascular volume status and fluid removal during a hemodialysis session. Usually, renal nurses rely on other, imprecise methods to determine ultrafiltration. To date, no study has examined whether renal nurses can reliably perform ultrasound for volume assessment and for potential prevention of intradialytic hypotension. This pilot study aimed to determine if a renal nurse could master the skill of performing and correctly interpreting Point of Care Ultrasound on patients receiving hemodialysis. Methods: After receiving theoretical training and performing 100 training scans, a renal nurse performed 60 ultrasound scans on 10 patients. These were categorized by the nurse into hypovolemic, euvolemic, or hypervolemic through measurement of the maximal diameter and degree of collapse of the IVC. Scans were subsequently assessed for adequacy and quality by two sonologists, who were blinded to each other's and the nurse's results. Findings: The interrater reliability of 60 scans was good, with intraclass correlation 0.79 (95% confidence interval (CI) =0.63–0.87) and with a good interrater agreement for the following estimation of intravascular volume (Cohen's weighted Kappa ?w = 0.62), when comparing the nurse to an expert sonographer. Discussion: A renal nurse can reliably perform ultrasound of the IVC in hemodialysis patients, obtaining high quality scans for volume assessment of hemodialysis patients. This novel approach could be more routinely applied by other renal nurses to obtain objective measures of patient volume status in the dialysis setting