Sudden Cardiac Death in Dialysis: Do Current Guidelines for Implantable Cardioverter Defibrillator Therapy Apply to Patients with End‐stage Kidney Disease?

Arrhythmic mechanisms account for one in four deaths in end-stage kidney disease. Large-scale randomized controlled trials have demonstrated a mortality benefit from implantable cardioverter defibrillator therapy in carefully selected patient groups at high risk for sudden cardiac death. Unfortunately, patients with end-stage kidney disease were systematically excluded from these trials. Consequently, the applicability of American College of Cardiology (ACC)/American Heart Association (AHA)/Heart Rhythm Society (HRS) guidelines on implantable cardioverter defibrillator therapy to dialysis patients remains uncertain. Observational data suggest that secondary preventative implantable cardioverter defibrillator therapy following resuscitated cardiac arrest prolongs the lives of dialysis patients. This intervention may also offer a survival advantage as a primary preventative strategy in end-stage kidney disease. However, competing risk from co-morbidity can negate any perceived benefit. Device-related complications also negatively impact outcome. The recommendation that primary preventative device implantation be reserved for patients with severely impaired left ventricular function may be excessively restrictive in this high-risk population. Trials of implantable cardioverter defibrillator therapy that include dialysis patients are required to validate existing device eligibility criteria in this unique population. Novel indications for this intervention in dialysis patients should also be identified.     

Epidemiology of renal dysfunction and patient outcome in atherosclerotic renal artery occlusion.

Patients with atherosclerotic renal artery occlusion (RAO) effectively have only a single functioning kidney, so they constitute an ideal group in whom to study the relationship of atherosclerotic renovascular disease (ARVD) severity to renal functional outcome. Of 299 patients with ARVD who had presented to a single center over a 12-yr period, 142 (47.5%) patients with RAO were identified. There was no relationship between baseline renal function and contralateral renovascular anatomy. Patients with contralateral normal, insignificant (<50%), or significant (>50%) renal artery stenoses had baseline creatinine of 243 +/- 235, 292 +/- 197, or 210 +/- 102 micromol/L, respectively, but patients with bilateral RAO (creatinine, 540 +/- 304 micromol/L; P < 0.0001) were significantly worse. There were significant correlations between baseline GFR and both proteinuria (r = -0.32; P < 0.01) and contralateral bipolar renal length (r = 0.44; P < 0.0001). Over a mean follow-up period of 31 +/- 21 (2 to 82) mo, the overall rate of progressive renal functional decline was -4.1 ml/min per yr. Nine patients required dialysis at presentation and a further 15 (10.5%) during the course of the study. There were 85 (59.9%) deaths; median survival of the whole group was 25 mo, and 5-yr survival was 31%. Multivariate analysis indicated that low baseline GFR was the chief variable independently associated with increased probability of death or need of dialysis but that renal vascular anatomy had no prognostic impact. This study reinforces the importance of intrarenal vascular and parenchymal disease in the etiology of renal dysfunction in ARVD.     

Postoperative Wound Oxygen Tension with Epidural or Intravenous Analgesia: A Prospective, Randomized, Single-blind Clinical Trial

Background: Adequate tissue oxygen tension is an essential requirement for surgical-wound healing. The authors tested the hypothesis that epidural anesthesia and analgesia increases wound tissue oxygen tension compared with intravenous morphine analgesia.

Methods: In a prospective, randomized, blind clinical study, the authors allocated patients having major abdominal surgery (n = 32) to receive combined general and epidural anesthesia with postoperative patient-controlled epidural analgesia (epidural group, n = 16), or general anesthesia alone with postoperative patient-controlled intravenous analgesia (intravenous group, n = 16). An oxygen sensor and a temperature sensor were placed subcutaneously in the wound before closure. Wound oxygen tension (Pwo2) and temperature were measured continuously for 24 h. Other variables affecting wound tissue oxygenation and visual analogue scale (VAS) pain scores were also documented.

Results: Despite epidural patients having lower body temperatures at the end of surgery (35.7 +/- 0.3) versus 36.3 +/- 0.5 [degrees]C, P = 0.004), they had significantly higher mean Pwo2 over the 24 h period, compared with the intravenous group (64.4 +/- 14 vs. 50.7 +/- 15) mmHg, mean (SD), 95% CI difference, -22 to -5, P = 0.002). Area under the Pwo2 -24 h time curve was also significantly higher in the epidural group (930 +/- 278 vs. 749 +/- 257) mmHg x h, 95% CI difference -344 to -18, P = 0.03). VAS pain scores at rest and moving were significantly lower in the epidural group at all times.     

Increased incidence of postoperative cognitive dysfunction 24 hr after minor surgery in the elderly

PURPOSE: Postoperative cognitive dysfunction (POCD) is evident in 26% of elderly patients seven days after major non-cardiac surgery. Despite the growing popularity of day surgery, the influence of anesthetic techniques on next day POCD has not been investigated. Therefore, we evaluated the incidence of POCD and changes in serum markers of neuronal damage (S-100ss protein and Neuron-Specific Enolase), 24 hr after single-agent propofol or sevoflurane anesthesia in elderly patients undergoing minor surgery. METHODS: Patients (n = 30, mean age 73, range 65-86 yr) coming for cystoscopy or hysteroscopy, were randomized, in an observer-blind design, to receive either single-agent propofol or sevoflurane anesthesia. Changes in neuropsychological tests (the Stroop test and the modified Word-Recall Test), 24 hr postoperatively were compared with age-matched control subjects (n = 15) using Z-score analysis. Changes in S-100beta protein and Neuron-Specific Enolase levels were also documented. RESULTS: POCD was present in 7/15 [47% (95% confidence interval (CI) 21 to 72%)] patients who received propofol and 7/15 [47% (95% CI 21 to 72%)] patients who received sevoflurane, compared with 1/15 [7% (95% CI 6 to 19%)] control patients, P = 0.03. S-100beta protein and Neuron-Specific Enolase levels were not significantly different in anesthetized patients postoperatively compared with preoperative values. CONCLUSION: The incidence of POCD in elderly patients on the first day after minor surgery is higher than previously reported for seven days after major surgery, and is increased after both propofol and sevoflurane anesthesia, compared with age-matched controls. S-100beta protein and Neuron-Specific Enolase levels were unaffected by anesthetic technique.     

Primary care-based disease management of chronic kidney disease (CKD), based on estimated glomerular filtration rate (eGFR) reporting, improves patient outcomes.

BACKGROUND: The majority of patients with chronic kidney disease (CKD) stages 3-5 are managed within primary care. We describe the effects, on patient outcomes, of the introduction of an algorithm-based, primary care disease management programme (DMP) for patients with CKD based on automated diagnosis using estimated glomerular filtration rate (eGFR) reporting. METHODS: Patients within West Lincolnshire Primary Care Trust, UK, population 223, 287 with CKD stage 4 or 5 were enrolled within the DMP between March 2005 and October 2006. We have analysed the performance against clinical targets looking at a change in renal function prior to and following joining the DMP and the proportion of patients achieving clinical targets for blood pressure control and lipid abnormalities. RESULTS: Four hundred and eighty-three patients with CKD stage 4 or 5 were enrolled in the programme. There were significant improvements in the following parameters, expressed as median values (interquartile range) after 9 months in the programme, compared to baseline and percentage values patients achieving target at 9 months: total cholesterol 4.2 (3.45-5.0) mmol/l versus 4.6 (3.9-5.4) mmol/l (P < 0.01), 75.0% versus 64.5% (P < 0.001); LDL 2.2 (1.6-2.8) mmol/l versus 2.5 (1.9-3.2) mmol/l (P < 0.01), 81.9% versus 69.2% (P < 0.05); systolic blood pressure 130 (125-145) mmHg versus 139 (124-154) mmHg (P < 0.05), 56.2% versus 37.1% (P < 0.05) and diastolic blood pressure 71 (65-79) mmHg versus 76 (69-84) mmHg (P < 0.01), 68.4% versus 90.3% (P < 0.01). The median fall (interquartile range) in eGFR in the 9 months prior to joining the programme was 3.69 (1.49-7.46) ml/min/1.73 m(2) compared to 0.32 (-2.61-3.12) ml/min/1.73 m(2) in the 12 months after enrolment (P < 0.001). One hundred and twenty-two patients experienced a fall in eGFR of > or = 5 ml/min/1.73 m(2), median 9.90 (6.55-12.36) ml/min/1.73 m(2) in the 9 months prior to joining the programme, whilst in the 12 months after enrolment, their median fall in eGFR was -1.70 (-6.41-1.64) ml/min/1.73 m(2) (P < 0.001). In the remaining patients, the median fall in eGFR was 1.92 (0.41-3.23) ml/min/1.73 m(2) prior to joining the programme and 0.86 (-1.03-3.53) ml/min/1.73 m(2) in the 12 months after enrolment (P = 0.082). CONCLUSIONS: These data suggest that chronic disease management in this form is an effective method of identifying and managing patients with CKD within the UK. The improvement in cardiovascular risk factors and reduction in the rate of decline of renal function potentially have significant health benefits for the patients and should result in cost savings for the health economy.     

Intraoperative pulmonary embolism of Harrington rod during spinal surgery: the potential dangers of rod cutting

This is a case report and laboratory-based biomechanics study. The objective is to report the first case of Titanium rod embolisation during scoliosis surgery into the Pulmonary artery. To investigate the potential of an unconstrained cut Titanium rod fragment to cause wounding with reference to recognised weapons. Embolisation of a foreign body to the heart is rare. Bullet embolisation to the heart and lungs is infrequently reported in the last 80 years. Iatrogenic cases of foreign body embolisation are very rare. Fifty 1–2 cm segments of Titanium rod were cut in an unconstrained manner and a novel method was used to calculate velocity. A high-speed camera (6,000 frames/s) was used to further measure velocity and study projectile motion. The wounding potential was investigated using lambs liver, high-speed photography and local dissection. Rod velocities were measured in excess of 23 m s⁻¹. Rods were seen to tumble end-over-end with a maximum speed of 560 revolutions/s. The maximum kinetic energy was 0.61 J which is approximately 2% that of a crossbow. This is sufficient to cause significant liver damage. The degree of surface damage and internal disruption was influenced by the orientation of the rod fragment at impact. An unconstrained cut segment of a Titanium rod has a significant potential to wound. Precautions should be taken to avoid this potentially disastrous but preventable complication.     

Methylphenidate and serum prolactin in man

Methylphenidate induces psychostimulation and increases cardiovascular parameters, and its psychostimulant effects have been proposed to occur via a dopaminergic mechanism. The effect of methylphenidate on serum prolactin was utilized as a method of evaluating methylphenidate's central dopaminergic effects. Methylphenidate was not found to exhibit a consistent effect on serum prolactin. Thus, its effect on serum prolactin does not parallel its behavioral activating properties, suggesting that such activation may not involve dopamine. Possibly, norepinephrine or other noncatecholaminergic neurotransmitters are involved in methylphenidate-induced behavioral activation.