Should peritoneal dialysis catheters be removed at the time of kidney transplantation?

Background:

Delayed graft function (DGF) following transplantation necessitates support in the form of hemodialyis (HD) or peritoneal dialysis (PD). However, post-transplant PD-related complication and failure rates are unknown.

Methods:

We studies patients who were on PD at the time of kidney transplantation over a 4-year period at two separate institutions.

Results:

Of the 137 PD patients, 19 had their catheters removed at the time of transplant. Of the remaining 118 patients, 89% had immediate graft function. PD-related complications in this group included peritonitis (n=5), catheter-related infections (n=2) and emergency laparotomy (n=1). Of the 15 patients requiring post-transplant PD, 33% developed peritonitis and 20% had fluid-leaks necessitating HD. Overall, leaving a PD catheter in situ post- transplantation is associated with 7% rate of peritonitis versus 0% if removed (p < 0.05).

Conclusions:

PD catheter removal should be considered at the time of renal transplantation, as postoperative PD-related failure/complication rates are high.     

Nitric oxide modulates renal vasoconstrictor effect of endothelin-1 in conscious lambs

To test the hypothesis that nitric oxide (NO) buffers the renal vasoconstrictor effects of endothelin-1 (ET-1) early in life, renal haemodynamic responses to ET-1 were measured in the presence and absence of endogenously produced NO in conscious lambs. Renal haemodynamic effects of ET-1 were measured for 5 min before (control) and 20 min after intraarterial injection of ET-1 before and after pretreatment with 20 mg/kg of the l-arginine analogue N^G-nitro-l-arginine methyl ester (l-NAME), (experiment 1) and its inactive isomer D-NAME (experiment 2) in conscious lambs aged ~1 week (N=7) and ~6 weeks (N=6). The two experiments were carried out in random order at intervals of 24–48 h. In lambs aged ~6 weeks, a marked increase in renal vascular resistance (RVR) was elicited by ET-1 administration; this response was enhanced twofold following pretreatment with l-NAME. In 1-week-old lambs, however, an increase in RVR in response to ET-1 occurred only after pretreatment with l-NAME. Therefore, we accept our hypothesis and conclude that NO buffers the renal vasoconstrictor effects of ET-1 early in life.The current address of Dr. Liesbeth van der Velde is UCLA Medical Center, Los Angeles, CA, USA. The current address of Dr. Alp Sener is University of Western Ontario, London, ON, Canada     

Risk factors for stroke following coronary artery bypass operations

BACKGROUND: Although the overall complication rates have been decreased significantly in recent years, stroke rates still remain high in patients undergoing coronary bypass operations. This study is designed to evaluate the risk factors for stroke in patients who had undergone coronary artery bypass surgery in an 8-year period in our clinic. METHODS: Between 1995 and 2003, 8547 coronary artery operations under cardiopulmonary bypass were performed. Retrospective analysis of the patient files revealed that 75 (0.9%) patients had stroke in the early postoperative period. RESULTS: Mean age of these patients was 62.3 +/- 9.5 years, and 54 (72%) were males. Stroke rate was 1.2% between 1995 and 1998 and this was significantly higher from the stroke rate (0.7%) of the period 1998 to 2003 (p = 0.03). Major technical differences between these two periods were the routine application of preoperative carotid arteries Doppler evaluation and intraoperative epiaortic echocardiography after 1998. Higher age (p = 0.000), female sex (p = 0.005), smoking (p = 0.03), presence of diabetes mellitus (p = 0.01), hypertension (p = 0.008), and left main coronary artery disease (p = 0.001), carotid surgery (p = 0.000), and peripheral vascular disease (p = 0.049) were identified as important risk factors in univariate analysis for stroke development. Higher age (p = 0.000; OR = 21.38), left main coronary artery disease (p = 0.007; OR = 7.26), peripheral vascular disease (p = 0.050; OR = 3.08), and operation date before 1998 (p = 0.012; OR = 6.33) were identified as important risk factors in logistic regression analysis. According to intraoperative epiaortic ultrasonography, operative strategy was changed in 9% of patients. Thirty-seven (49.3%) of the stroke patients died. Female sex (p = 0.023; OR = 5.18) and preoperative hypertension (p = 0.045; OR = 4.03) were observed as significant risk factors for mortality after stroke. CONCLUSION: Development of stroke is one of the major reasons of mortality after coronary artery bypass operations. It is essential to take all the measures to prevent this complication, especially in patients with known risk factors. Evaluation of carotid arteries prior to operation and application of routine intraoperative epiaortic echocardiography may in part eliminate stroke.     

Immediate Continence Rates in RALRP: A Comparison of Three Techniques

Methods:We retrospectively analyzed the patients who underwent RALRP for localized prostate cancer by a single surgeon in our clinic from January 1, 2009–February 1, 2016. Continence was defined as no leakage or use of a safety pad for minimal leakage. The main outcome measure was continence at postoperative week 1 and months 1, 6, and 12.Results:Between 2009 and 2016, 239 patients underwent RALRP for localized prostate disease. Seventy-four patients underwent a standard approach (group 1), 88 had posterior reconstruction (group 2), and 77 had posterior reconstruction with total anatomic restoration (group 3). After 1 week, 24.3% of the patients in group 1 (18/74), 31.8% in group 2 (28/88), and 45.8% in group 3 (33/72) were continent (P = .02). One month after the surgery, continence rates for groups 1, 2, and 3 were 56.7, 67, and 75%, respectively (0.065). After 6 and 12 months, continence rates for groups 1, 2, and 3 were 72.9 and 87.8%, 81.8 and 89.7%, and 84.7 and 91.6%, respectively (P = .178 and .7484).Conclusion:Anatomic restoration improves continence rates in the early period after RALRP. Even though other parameters were higher in the total restoration group, immediate continence (at 1 week) was significantly better.     

Infantile tuberous sclerosis changes in the brain: proton MR spectroscopy findings.

A parietal hamartoma of a three-month-old boy with tuberous sclerosis was studied with magnetic resonance (MR) imaging, and proton MR spectroscopy. MR spectra were obtained with the single-voxel PRESS (point resolved spectroscopy; TR = 1500 ms, TE = 135 ms) sequence, in a 8 cc region of interest. Apparently low NAA/Cho (0.28), and NAA/Cr (0.37) ratios were noted in the hamartoma, that could suggest a neoplasm. The lesion and the surrounding brain tissue were studied again after seven months with spectroscopic imaging using the chemical shift sequence (TR = 1500 ms. TE = 40 ms). This study revealed apparently improved NAA/Cho (2.63), NAA/Cr (2.13) ratios in the hamartoma compared to the initial examination at three months of age, excluding the possibility of a neoplasm.     

Protective effect of N-acetylcysteine on renal ischemia/reperfusion injury in the rat

BACKGROUND: Oxygen free radicals are important components involved in the pathophysiological tissue alterations observed during ischemia/reperfusion (I/R). METHODS: The protective effect of N-acetylcysteine (NAC) against the damage inflicted by reactive oxygen species during renal I/R was investigated in Wistar Albino rats using biochemical parameters. Animals were unilaterally nephrectomized, and subjected to 45 min of renal pedicle occlusion followed by lh of reperfusion. N-acetylcysteine (150 mg/kg, i.p.) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were killed by decapitation. For biochemical analysis, the lipid peroxidation product malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and protein oxidation (PO) were tested. Serum creatinine and BUN concentrations were measured for the evaluation of renal function. RESULTS: I/R induced nephrotoxicity, as evidenced by increases in BUN and creatinine, was reversed by NAC. The decrease in GSH and increases in MDA, MPO and PO induced by I/R indicated that renal injury involves free radical formation. CONCLUSIONS: Since NAC reversed these oxidant responses, and protected rat renal proximal tubules from in vitro simulated reperfusion injury, it seems that NAC protects kidney tissue against oxidative damage.     

Effect of timing of chest tube removal on development of pericardial effusion following cardiac surgery

BACKGROUND: There are no standard criteria for the timing of drain removal. The objective of this study was to determine whether the macroscopic appearance of chest tube drainage fluid to serosanguineous may be used as a criteria for drain removal. METHODS: 2,359 patients were assessed retrospectively and 80 randomized patients were followed prospectively who underwent cardiac surgery. In both parts of the study, patients were divided into two groups according to the timing of drain removal. Group I consisted of patients whose chest tubes were removed as soon as the macroscopic appearance of the drainage fluid turned to serosanguineous. Group II consisted of patients whose chest tubes were removed at the second postoperative day when the drainage output declined to less than 50 mL in a five-hour period. In the retrospective part, cases of hemodynamically significant pericardial effusion observed within seven days postoperatively were reviewed. In the prospective part, just before the drain removal, the fluid sample hematocrit obtained from the drain lines and patients' blood hematocrit were measured and recorded. Patients were evaluated with echocardiography for pericardial effusion. RESULTS: No statistically significant difference was detected in the frequency of hemodynamically significant pericardial effusion and incidence or amount of pericardial effusion between the two study groups. The drain hematocrit to blood hematocrit ratios before drain removal showed a significant correlation with pericardial effusion.The strength of correlation between the drain hematocrit to blood hematocrit ratios before drain removal and pericardial effusion was also studied using receiver operating characteristic curve, which suggests that a drain hematocrit to blood hematocrit ratio of < or = 0.3 is strongly predictive that pericardial effusion would be absent or mild between the fifth and seventh postoperative days. CONCLUSIONS: It is safe to remove the chest tubes as soon as the macroscopic appearance of the drainage fluid turns to serosanguineous since this practically indicates cessation of active bleeding.     

Kotz and Ganz osteotomies in the treatment of adult acetabular dysplasia

In hips with acetabular dysplasia, we performed Kotz osteotomy (group 1) in 22 hips (20 patients; mean age 24.3 years) and Ganz osteotomy (group 2) in 23 hips (22 patients; mean age 23.1 years). Group 1 was followed 83.3 (56-112) months and group 2 40.9 (24-66) months. In group 1, Harris hip score improved from average 74.9 to 86.9, mean center edge (CE) angle from -4.5 degrees to 30.3 degrees, and mean vertical center edge (VCE) angle from 5.3 degrees to 36.2 degrees. In group 2, Harris hip score improved from average 76.6 to 91.1, mean CE angle from -5.9 degrees to 32.0 degrees, and mean VCE angle from 5.0 degrees to 41.3 degrees. Using Pauwels criteria, regression was observed in 12 hips in group 1 and one progressed. In group 2, 15 hips showed regression and three progressed. In patients treated with Ganz osteotomy, the complication rate was higher and the complications more serious than in patients treated with Kotz osteotomy. Most complications were, however, seen among the first ten patients treated with Ganz osteotomy. Although we detected no significant difference between the two groups in terms of clinical and radiological findings, we believe the outcome to be slightly better after a properly performed Ganz osteotomy.     

Neuroprotective effects of alpha-lipoic acid in experimental spinal cord injury in rats

Background:

Oxidative stress is a mediator of secondary injury to the spinal cord following trauma.

Objective:

To investigate the putative neuroprotective effect of α-lipoic acid (LA), a powerful antioxidant, in a rat model of spinal cord injury (SCI).

Methods:

Wistar albino rats were divided as control, vehicle-treated SCI, and LA-treated SCI groups. To induce SCI, a standard weight-drop method that induced a moderately severe injury (100 g/cm force) at T10 was used. Injured animals were given either 50 mg/kg LA or saline at 30 minutes postinjury by intraperitoneal injection. At 7 days postinjury, neurologic examination was performed, and rats were decapitated. Spinal cord samples were taken for histologic examination or determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and DNA fragmentation. Formation of reactive oxygen species in spinal cord tissue samples was monitored by using a chemiluminescence (CL) technique.

Results:

SCI caused a significant decrease in spinal cord GSH content, which was accompanied with significant increases in luminol CL and MDA levels, MPO activity, and DNA damage. Furthermore, LA treatment reversed all these biochemical parameters as well as SCI-induced histopathologic alterations. Conversely, impairment of the neurologic function caused by SCI remained unchanged.

Conclusion:

The present study suggests that LA reduces SCI-induced oxidative stress and exerts neuroprotection by inhibiting lipid peroxidation, glutathione depletion, and DNA fragmentation.     

Dentin enhances the effectiveness of bioactive glass S53P4 against a strain of Enterococcus faecalis.

OBJECTIVE: The aim of the current study was to test the impact of dentin powder on the antimicrobial efficacy of bioactive glass S53P4 (BAG). STUDY DESIGN: BAG was suspended (preincubated) in saline at 37 degrees C for different time periods with or without human dentin powder, hydroxylapatite, or decalcified dentin. Subsequently, Enterococcus faecalis ATCC 29212 cells were added to these suspensions and bacterial recovery measured with and without the use of gentle sonication. Furthermore, survival of bacteria in test and control suspensions was assessed over time. Supernatants of suspensions were analyzed for their element contents using atomic absorption spectrophotometry. The effects of pH, silica, and osmolarity on E faecalis viability were assessed using specifically prepared solutions. RESULTS: BAG preincubated with dentin powder caused a significant (P < .05) decrease in viability compared to pure BAG suspensions. This was not based on adherence of bacteria to solid particles or agglutination of the cells, because sonication did not increase bacterial yields. Hydroxylapatite and decalcified dentin did not increase BAG killing efficacy. The additive effect of BAG + dentin powder was dose dependent, occurred only with solids in suspension, and increased with suspension time. An augmented dissolution of glass components, especially silicon, was measured in BAG + dentin powder compared to pure BAG suspensions or counterparts containing hydroxylapatite or decalcified dentin. High osmolarity per se did not affect E faecalis viability, whereas high pH and silica levels did. CONCLUSION: The observed phenomenon was related to an increased BAG dissolution triggered by dentin powder, causing elevated local pH and silica levels.