Commercial Low-citrate Anticoagulation Haemofiltration in High Risk Patients with Frequent Filter Clotting

This study assessed the safety and efficacy of a commercial low-citrate concentration-based pre-filter replacement fluid during continuous veno-venous haemofiltration (CVVH) in patients with frequent filter clotting and high risk of bleeding. We used a commercial low-citrate fluid as pre-dilution replacement fluid during CVVH (citrate: 11 mmol/l (33 meq/l), sodium: 140 mmol/l, chloride: 108 mmol/l and potassium: 1 mmol/l). A calcium and magnesium infusion was delivered separately by central line for the maintenance of serum ionized calcium (Cai) and total magnesium (Mg). In this prospective observational study, 30 patients, 124 filters and 1,515 treatment-hours were observed. Median filter life of citrate CVVH was 9.5 hours. Filter life in the 48 hours prior to citrate CVVH was also observed. In the patients on prior non-anticoagulant CVVH (n=14) filter life increased significantly with citrate (9.5 hours vs 5 hours; P<0.0001). In patients on prior heparin CVVH (n=15), filter life was similar with citrate (10 hours vs 8 hours; P=0.68). However, in patients with prior early/frequent filter clotting despite heparin (n=11) filter life increased significantly (10 hours vs 7 hours; P=0.038). Of 411 serum Cai measurements, none showed a Cai<0.85 mmol/l and, of 84 observations, none showed a serum Mg<0.6mmol/l. One patient with sepsis and shock needed to cease citrate CVVH because of progressive ionized hypocalcaemia and increasing anion gap. No other adverse effects were observed. In selected patients, CVVH with a commercial low-citrate concentration solution as pre-filter replacement fluid and a simultaneous calcium and magnesium infusion protocol appears generally safe. Filter life was acceptable and superior to that achieved with previous treatment.

A Comparison of 4% Succinylated Gelatin Solution versus Normal Saline in Stable Normovolaemic Sheep: Global Haemodynamic, Regional Blood Flow and Oxygen Delivery Effects

The objective of this study was to compare the effects on regional blood flow and regional oxygen delivery of 4% succinylated gelatin solution (Gelofusine®, B. Braun) with those of normal saline. This was a randomised, controlled, crossover large animal study, which took place at the animal laboratory of university physiology institute. The subjects were seven merino cross-ewes.

We implanted flow probes around the aorta, coronary, renal and mesenteric arteries. We randomised animals to observation (control), normal saline (one litre over 15 minutes) or Gelofusine* (one litre over 15 minutes). We measured central haemodynamics, organ blood flows, arterial blood gases and haemoglobin every 30 minutes for 210 minutes.

Compared to control, both Gelofusine* and normal saline significantly and similarly increased mean arterial pressure, stroke volume, cardiac output and central venous pressure in the first hour (P <0.05). Such changes, however, were transient except for the increase in cardiac output seen with Gelofusine®. Normal saline significantly increased mesenteric blood flow in the first hour (P <0.05), while Gelofusine* caused a specific, sustained and progressive increase in renal blood flow and conductance (P <0.05). Both fluids increased urine output and creatinine clearance (P <0.05), but, due to haemodilution, both decreased renal oxygen delivery in the first hour (P <0.05).

Normal saline and Gelofusine® have transient, volume expansion-related systemic haemodynamic effects, which are greater for Gelofusine®. Saline had a more pronounced early effect on mesenteric blood flow, while Gelofusine* had a sustained and progressive greater effect on renal blood flow. The transient increase in urine output and creatinine clearance seen with both fluids occurred while renal oxygen delivery decreased.

Time-dependent Effects of Pressure during Preservation of Rat Hearts in an Isochoric System at Subfreezing Temperatures

BACKGROUND

Isochoric freezing systems enable ice-free preservation of biological matter at subfreezing temperatures under the increased hydrostatic pressure.

OBJECTIVE

To examine the effects of pressure and exposure period on rat hearts preserved in an isochoric chamber.

MATERIALS AND METHODS

Rat hearts were preserved in the UW solution in isochoric chambers at temperatures from -2°C to -8°C and pressure from the atmospheric level to 78 MPa for up to eight hours, with and without the addition of glycerol. Hearts were evaluated via Langendorff perfusion and HE histology.

RESULTS

Hearts were compromised quickly as pressure increased, suggesting an acute time-pressure sensitivity. With the addition of 1 M glycerol, which reduces the pressure experienced at a given temperature, the survival time at -4°C was doubled.

CONCLUSION

The enhanced hydrostatic pressure encountered during isochoric preservation yields time-dependent negative effects on the heart, which can potentially be alleviated by the addition of a cryoprotectant.

Assessment of the Original Height of L1~2 after Vertebral Compression Fracture

OBJECTIVES

To explore the assessment method of original height of L_1-2 after vertebral compression fracture and its application value in forensic clinical practice.

METHODS

A total of 154 normal thoracic and lumbar X-ray films were collected, and 140 cases were used as experimental group while 14 cases as validation group. The heights of anterior （Ha） and posterior （Hp） vertebral body of T₁₂-L₃ vertebrae in each X-ray image were measured. In the experimental group, the correlation analysis between Ha_L₁ and Ha_T₁₂, Hp_T₁₂, Hp_L₁, Ha_L₂ and Hp_L₂ was carried out, and regression equation was established via fitting. The correlation analysis between Ha_L₂ and Ha_L₁, Hp_L₁, Hp_L₂, Ha_L₃, Hp_L₃ was performed, and the regression equation was also established via fitting. The difference between the predicted and measured values of Ha_L₁ and Ha_L₂ in validation group was compared.

RESULTS

In the 140 normal subjects, Ha_L₁ （y₁） was well correlated with Ha_T₁₂ （x₁） and Ha_L₂（x₂）, and the multiple linear regression equation was y₁=2.545+0.423 x₁+0.486 x₂ （determining coefficient R²=0.712, P<0.05; F=169.206, P<0.05）. There was no significant difference between the predicted and actual measured values of Ha_L₁ in the validation group （ P>0.05）. HaL₂ （y₂） was well correlated with Ha_L₁ （x₃） and Ha_L₃ （x₄）, and the multiple linear regression equation was y₂=4.354+0.530 x₃+0.349 x₄ （determining coefficient R²=0.689, P<0.05; F=151.575, P<0.05）. There was no significant difference between the predicted and actual measured values of Ha_L₂ in the validation group （ P>0.05）.

CONCLUSIONS

It is more appropriate to evaluate the original height of L₁ or L₂ single vertebrae by comparing with the height of the anterior edge of the upper and lower adjacent vertebral bodies.

Structure-guided development of YEATS domain inhibitors by targeting π-π-π stacking

Chemical probes of epigenetic 'readers' of histone post-translational modifications (PTMs) have become powerful tools for mechanistic and functional studies of their target proteins in normal physiology and disease pathogenesis. Here we report the development of the first class of chemical probes of YEATS domains, newly identified 'readers' of histone lysine acetylation (Kac) and crotonylation (Kcr). Guided by the structural analysis of a YEATS-Kcr complex, we developed a series of peptide-based inhibitors of YEATS domains by targeting a unique π-π-π stacking interaction at the proteins' Kcr recognition site. Further structure optimization resulted in the selective inhibitors preferentially binding to individual YEATS-containing proteins including AF9 and ENL with submicromolar affinities. We demonstrate that one of the ENL YEATS-selective inhibitors, XL-13m, engages with endogenous ENL, perturbs the recruitment of ENL onto chromatin, and synergizes the BET and DOT1L inhibition-induced downregulation of oncogenes in MLL-rearranged acute leukemia.

Search for Boosted Dark Matter Interacting with Electrons in Super-Kamiokande

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

Spermatogenesis-associated 48 is essential for spermatogenesis in mice

Azoospermia, oligospermia and teratozoospermia all seriously impact male reproductive health. Spermatogenesis is a complex and precisely regulated process in which germ cells proliferate and differentiate and involves the regulation of multiple testis-specific genes. Here, we identified testis-specific gene spermatogenesis-associated 48 (SPATA48), the expression of which was age-dependent, indicating that it is involved in spermatogenesis. In humans and mice with azoospermia, expression of SPATA48 disappeared in the testis. Spata48-/- knockout male mice had smaller testis and defective spermatogenesis compared to wild-type (WT) mice. This study can help in the exploration of the genetic basis of male infertility and identify new targets for the diagnosis and treatment of male infertility.

Block iliac bone grafting enhances osseous healing of alveolar reconstruction in older cleft patients: A radiological and histological evaluation

Background

Older alveolar cleft patients (&12 years old) often have wide bone defect as well as teeth loss, resulting in poor osseous healing with conventional alveolar bone grafting (ABG). In this study, we investigated a surgical technique of block iliac bone grafting for the alveolar cleft reconstruction and evaluated the clinical and radiological outcomes of these cleft patients.

Material and Methods

Fifteen patients were included in this study. All cases received preoperative cone bean computed tomography (CBCT) scans for the alveolar cleft evaluation. Osseous outcomes of block iliac bone grafting were assessed at 1 week, 3- and 6-month postoperatively. Volume changes and bone resorption rates were calculated using the measurement modules of Simplant software. Bone samples from one patient undergoing dental implantation were assessed by micro-CT and histological examination. The morbidities of donor-site were analyzed by clinical examination and questionnaire survey.

Results

The average age of the case series was 18.53±2.50 years. The intraoral incision of thirteen cases healed well. However, two cases had oronasal fistula and graft exposure at 1-week postoperatively. The results of follow-up CBCT scans showed significant resistance to radiation on both sides of the bone graft, suggesting a good osseous healing and new bone formation. The mean residual bone volume was 1.68±0.26 cm3, 1.29±0.23 cm3 and 1.15±0.23 cm3 at 1-week, 3- and 6-month postoperatively. Correspondingly, the mean bone resorption rates in 3- and 6-month postoperative were 21.78±6.88% and 30.66±8.97%, respectively. From micro-CT and HE examinations, the block bone samples exhibited a cancellous structure in which mature bone trabecula and functional blood vessels appeared. The average scores of donor-site morbidities were drastically decreased at 3- and 6-month postoperatively compared with those at 1-week postoperatively.

Conclusions

Our results demonstrated that block iliac bone grafting could achieve satisfying osseous outcomes in older alveolar cleft patients, and this technique provided favorable bony condition for further treatments, especially dental implantation.

Key words:Alveolar bone grafting, Block bone grafting, Osseous healing, CBCT.

[Automated Assessment for Bone Age of Left Wrist Joint in Uyghur Teenagers by Deep Learning]

OBJECTIVES

To realize the automated bone age assessment by applying deep learning to digital radiography （DR） image recognition of left wrist joint in Uyghur teenagers, and explore its practical application value in forensic medicine bone age assessment.

METHODS

The X-ray films of left wrist joint after pretreatment, which were taken from 245 male and 227 female Uyghur nationality teenagers in Uygur Autonomous Region aged from 13.0 to 19.0 years old, were chosen as subjects. And AlexNet was as a regression model of image recognition. From the total samples above, 60％ of male and female DR images of left wrist joint were selected as net train set, and 10％ of samples were selected as validation set. As test set, the rest 30％ were used to obtain the image recognition accuracy with an error range in ±1.0 and ±0.7 age respectively, compared to the real age.

RESULTS

The modelling results of deep learning algorithm showed that when the error range was in ±1.0 and ±0.7 age respectively, the accuracy of the net train set was 81.4% and 75.6% in male, and 80.5% and 74.8% in female, respectively. When the error range was in ±1.0 and ±0.7 age respectively, the accuracy of the test set was 79.5% and 71.2% in male, and 79.4% and 66.2% in female, respectively.

CONCLUSIONS

The combination of bone age research on teenagers' left wrist joint and deep learning, which has high accuracy and good feasibility, can be the research basis of bone age automatic assessment system for the rest joints of body.

[Opportunistic infection in systemic lupus erythematosus patients: the disease spectrum and the characteristics of peripheral lymphocyte subsets]

Objective: To investigate the common opportunistic infections and the characteristics of peripheral lymphocyte subsets in patients with systemic lupus erythematosus (SLE). Methods: From December 2013 to December 2016, peripheral lymphocyte subsets were consecutively detected by flow cytometry in treated SLE patients with or without opportunistic infections (OIs) . The lymphocyte subsets in healthy donors were used as normal control group. Results: A total of 145 treated SLE patients were enrolled including 108 with OIs and 37 without OIs. The common OIs were cytomegalovirus (CMV) diseases (66/108), Pneumocystis jirovecii pneumonia (PJP, 16/108), other fungal infections (16/108), Epstein-Barr virus (EBV, 15/108) and tuberculosis (14/108). Compared with treated SLE without OIs, total lymphocyte, CD(4+) T, and CD(8+) T lymphocyte counts were significantly reduced in SLE with OIs [1 260 (780, 1 810) cells/μl vs. 565 (399, 1 043) cells/μl, P<0.001; 485 (280, 811) cells/μl vs. 173 (95, 327) cells/μl, P<0.001; 464 (339, 764) cells/μl vs. 265 (158, 424) cells/μl, P=0.003, respectively]. Conclusions: The common OIs in treated SLE patients were CMV diseases, PJP, other fungi, EBV and tuberculosis. OIs are prone to develop in SLE patients with severe lymphocytopenia, especially CD(4+) T cell depletion.

Abstract P4-03-16: Cyclin E affects Smad3 pathway in trastuzumab resistant HER2+ breast cancer

Introduction and Objective: HER2 amplification is found in approximately 20% of patients with breast cancer and is associated with poor prognosis. Trastuzumab, a humanized anit-HER2 antibody, has been shown to improve patient outcomes, but clinical efficacy for this treatment is limited by the high rate of drug resistance. Cyclin E overexpression and cyclin-dependent kinase 2 (CDK2) activation correlate with trastuzumab resistance, and the underlying mechanisms of this correlation are an area of active study. In this work, we examined the contribution of cyclin E/CDK2-mediated Smad3 noncanonical phosphorylation to trastuzumab resistance in HER2+ breast cancer.

Methods: Trastuzumab resistant BT474R2 cells were developed by culturing BT474 cells in trastuzumab-supplemented media for 18 months. These cells were then inoculated into immunodeficient mice and treated with trastuzumab twice weekly. BT474 and BT474R2 cells were used to study cell proliferation, phosphorylation in the Smad3 linker region and transcription factor activities with a living cell array.

Results: Inhibition of cyclin E activity with CDK2 inhibitor therapy (CDK2i, 600 nM) significantly decreased BT474R2 cell proliferation. CDK2i treatment led to decreased phosphorylation at T179 (p&lt;0.01), S204 (p&lt;0.01) and S213 (p&lt;0.05) in the Smad linker region. Further, CDK2i increased expression of p15 (p&lt;0.05) and decreased expression of c-myc (p&lt;0.05) in comparison with trastuzumab treatment. Transduction of BT474R2 cells with a 5M Smad3 construct containing inhibitory mutations in 5 CDK2 phosphorylation sites resulted in decreased cell proliferation. In a transfected cell array using BT474 and BT474R2 cells, activities of cell proliferation and metastasis-associated transcription factors were significantly different between the trastuzumab sensitive and resistant cells.

Conclusions: Taken together, overexpression of cyclin E leads to Smad3 noncanonical phosphorylation and results in trastuzumab resistance in HER2+ breast cancer. CDK2i treatment may be a promising therapeutic strategy for patients with trastuzumab resistance.

Citation Format: Decker JT, Wan L, Shea LD, Jeruss JS. Cyclin E affects Smad3 pathway in trastuzumab resistant HER2+ breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-03-16.

Videolaryngoscopy vs. Macintosh laryngoscopy for double-lumen tube intubation in thoracic surgery: a systematic review and meta-analysis

Double-lumen intubation is more difficult than single-lumen tracheal intubation. Videolaryngoscopes have many advantages in airway management. However, the advantages of videolaryngoscopy for intubation with a double-lumen tube remain controversial compared with traditional Macintosh laryngoscopy. In this study, we searched MEDLINE, Embase, Cochrane Library and the Web of Science for randomised controlled trials comparing videolaryngoscopy with Macintosh laryngoscopy for double-lumen tube intubation. We found that videolaryngoscopy provided a higher success rate at first attempt for double-lumen tube intubation, with an odds ratio (95%CI) of 2.77 (1.92-4.00) (12 studies, 1215 patients, moderate-quality evidence, p < 0.00001), as well as a lower incidence of oral, mucosal or dental injuries during double-lumen tube intubation, odds ratio (95%CI) 0.36 (0.15-0.85) (11 studies, 1145 patients, low-quality evidence, p = 0.02), and for postoperative sore throat, odds ratio (95%CI) 0.54 (0.36-0.81) (7 studies, 561 patients, moderate-quality evidence, p = 0.003), compared with Macintosh laryngoscopy. There were no significant differences in intubation time, with a standardised mean difference (95%CI) of -0.10 (-0.62 to 0.42) (14 studies, 1310 patients, very low-quality evidence, p = 0.71); and the incidence of postoperative voice change, odds ratio (95%CI) 0.53 (0.21-1.31) (7 studies, 535 patients, low-quality evidence, p = 0.17). Videolaryngoscopy led to a higher incidence of malpositioned double-lumen tube, with an odds ratio (95%CI) of 2.23 (1.10-4.52) (six studies, 487 patients, moderate-quality evidence, p = 0.03).

Resistance of vascular access catheters for continuous renal replacement therapy: An ex vivo evaluation

Aim

To assess the resistance posed by double-lumen vascular access dialysis catheters at low and high blood flow.

Design

Controlled ex vivo study

Setting

ICU Laboratory of tertiary hospital.

Subjects

Eleven proprietary vascular access catheters for continuous renal replacement therapy. Methods: Heparinized spent red cells diluted in polygeline solution were pumped using the Aquarius hemofiltration machine (Edwards Life Sciences, Sydney, NSW, Australia) and its standard circuit through several vascular access catheters. Blood flow was increased and then decreased in steps of 50 ml/min (50, 150, 200, 250 and 300 ml/min) while catheter outflow and inflow pressures were recorded. The pressure-flow relationship (hydraulic resistance) of each catheter was then calculated. Study catheters were divided into two groups according to their internal diameter (large gauge vs. smaller gauge) or length (long or short). Hydraulic resistances were compared between the groups. Results: Different double lumen catheters posed clearly different resistances to flow. For all groups of catheters, there was a linear relationship between pressure and flow. No statistically significant difference between short and long catheters could be demonstrated (p=0.715). On the other hand, larger gauge catheters (13 Fr or greater) had significantly lower resistances than smaller gauge (<13 Fr) catheters (p=0.0062). Furthermore, all larger gauge catheters had resistances lower than 0.430 mmHg/ml/min, while all smaller gauge catheters had resistances greater than 0.490 mmHg/ml/min. Conclusions: Commercial double-lumen dialysis catheters have variable resistance to blood flow under standard ex vivo conditions. Although both length and internal diameter varied, internal diameter had a dominant effect on resistance. This information might be useful to clinicians in guiding their choice of catheters for clinical use. (Int J Artif Organs 2008; 31: 905–9)

Acid-Base Balance during Continuous Veno-Venous Hemofiltration: The Impact of Severe Hepatic Failure

Background

Continuous renal replacement therapy (CRRT) affects acid-base balance but the influence of severe hepatic failure (SHF) on this effect is unknown.

Aim

To assess the effect of SHF on acid-base balance in patients receiving CVVH.

Design

Retrospective laboratory investigation.

Subjects

Forty patients with SHF and acute renal failure (ARF) treated with CVVH and 42 critically ill patients with severe ARF but no liver disease also treated with CVVH (controls).

Intervention

Retrieval of clinical and laboratory data from prospective unit and laboratory databases.

Methods

Quantitative acid-base status assessment using the Stewart-Figge methodology. Comparison of findings between the two groups.

Results

Although CVVH had a major effect on acid base balance in both groups, patients with SHF had a higher mean lactate concentrations (4.8 vs. 3.1 mmol/L; p<0.0005), a greater base deficit compared to controls (-1 vs. 4.1 mEq/L; p<0.0001) and a lower PaCO2 tension (36.8 vs. 42.5 mmHg; p<0.0001), despite the use of bicarbonate replacement fluid. The acidifying effect of hyperlactatemia was slightly worsened by an increased strong ion gap (9.3 vs. 4.9 mEq/L; p<0.0001). It was, however, attenuated by an increased strong ion difference apparent (SIDa) (43.6 vs. 41.9 mEq/L; p<0.05) secondary to hypochloremia (96 vs. 100 mmol/L; p<0.0001) and by hypoalbuminemia, although hypoalbuminemia in SHF patients (26 vs. 23; p<0.005) was less pronounced than in controls.

Conclusion

The use of CVVH does not fully correct the independent acidifying effect of liver failure on acid-base status. Increased lactate and strong ion gap values maintain a persistent base deficit despite the alkalinizing effects of hypoalbuminemia and hypochloremia. The correction of acidosis in SHF patients may require more intensive CVVH.

Low-dose Citrate Continuous Veno-venous Hemofiltration (CVVH) and Acid-base Balance

Objective

To evaluate the acid-base effect of low-dose regional citrate anticoagulation (RCA) during continuous veno-venous hemofiltration (CVVH).

Design

Prospective observational study.

Setting

ICUs of tertiary public and private hospitals.

Subjects

Thirty critically ill patients with acute renal failure at risk of bleeding or with a major contraindication to heparin-CVVH and/or short filter life.

Methods

We used a commercial citrate-based fluid (11 mmol/L, sodium: 140 mmol/L, chloride: 108 mmol/L and 1 mol/L of potassium) as pre-dilution replacement fluid during CVVH. Further potassium was added according to serum potassium levels. We measured all relevant variables for acid-base analysis according to the Stewart-Figge methodology.

Results

Before treatment, study patients had a slight metabolic acidosis, which worsened over 6 hours of RCA-CVVH (pH from 7.39 to 7.38, p<0.005; bicarbonate from 23.2 to 21.6 mmol/L, p<0.0001 and base excess from −2.0 to −3.0 mEq/L, p<0.0001) due to a significant increase in SIG (from 5.8 to 6.6 mEq/L, p<0.05) and a decrease in SIDa (from 37.5 to 36.6 mEq/L, p<0.05). These acidifying effects were attenuated by hypoalbuminemia and a decrease in lactate (from 1.48 to 1.34 mmol/L, p<0.005) and did not lead to progressive acidosis. On cessation of treatment, this acidifying effect rapidly self-corrected within six hours.

Conclusions

Low dose RCA-CVVH induces a mild acidosis secondary to an increased strong ion gap and decreased SIDa which fully self-corrects at cessation of therapy. Clinicians need to be aware of these effects to correctly interpret changes in acid-base status in such patients.

Acid-base Balance in Combined Severe Hepatic and Renal Failure: A Quantitative Analysis

Background

Severe hepatic failure (SHF) commonly leads to major changes in acid-base balance status. However, the direct effects of liver failure per se on acid base balance are poorly understood because this condition is usually associated with acute renal failure (ARF).

Aim

To assess the effect of SHF on acid-base balance.

Design

Retrospective laboratory investigation.

Subjects

Thirty-seven critically ill patients with SHF complicated by ARF, and 42 patients with severe ARF without liver failure prior to renal replacement therapy.

Intervention

Retrieval of clinical and laboratory data from prospective unit and laboratory databases.

Methods

Quantitative acid-base assessment using Stewart-Figge methodology. Comparison of findings between the two groups. Comparison of demographic and clinical features.

Results

Patients with combined SHF and ARF were younger and had significantly higher mean bilirubin, ALT and INR levels (p<0.0001). Their mean lactate concentration was higher (6.4 vs. 2.1 mmol/L; p<0.0001) leading to a greater anion gap (25.8 vs. 16.1 mmol/L; p<0.0001). The ionized calcium concentration (1.00 vs. 1.15 mmol/L; p<0.0001) was lower but the strong ion difference apparent (SIDa) was greater (42.0 vs. 38.0 mEq/L; p<0.005) due to hypochloremia. The albumin concentration was low but higher than in control patients (28 vs. 24 g/L; p<0.01) and the calculated strong ion gap (SIG) was greater (12.6 vs. 9.3 mEq/L; p<0.01). The base excess was similar to controls and the pH was preserved in the near normal range by marked hypocapnea.

Conclusions

Combined SHF and ARF is a syndrome with unique acid-base changes due mostly to lactic metabolic acidosis and, in smaller part, to the accumulation of unmeasured anions. This acidosis, like that of ARF, is attenuated by hypoalbuminemia, by a unique preservation of the SIDa due to hypochloremia, and by marked hypocapnea.

Prolonged Daily Intermittent Renal Replacement Therapy in ICU Patients by ICU Nurses and ICU Physicians

Objectives

Prolonged daily intermittent renal replacement therapy (PDIRRT) has been proposed as a new form of treatment for severe acute renal failure (ARF). However, this treatment has so far implied a) full dependence on nephrological input, b) lack of any convective clearance and c) limited purification of dialysate water. The aim of this study was to establish the feasibility and safety of performing PDIRRT in the ICU with a) no nephrological input, b) the addition of some convective clearance with on-line fluid replacement and c) a new advanced water purification system.

Design

Prospective observational study.

Patients

Fourteen patients treated with PDIRRT.

Setting

ICU of tertiary institution.

Interventions

Treatment of patients with severe ARF and critical illness with PDIRRT. Prescription of treatment by ICU physicians. Conduct of treatment by ICU nurses. Use of combined convective and diffusive therapy with on-line generation of fluid replacement, application of a double-filtration water purification system.

Measurements and Main Results

We prospectively collected demographic, biochemical, hemodynamic and clinical data in 14 patients, who received 30 PDIRRT treatments for a cumulative treatment time of 205.4 hours. The mean age was 57.9 ± 16.0. Eight patients were male and 6 female. Their mean APACHE II score was 24.6 ± 5.9 and their SAPS II score was 41.7 ± 18.8. PDIRRT was used after at least 24 hours of initial stabilization with continuous veno-venous hemofiltration (CVVH). Blood flow was kept at 100ml/min dialysate flow at 200 ml/min and convective clearance varied from 21 ml/min to 33 ml/min. All patients were either anuric or oliguric (UO < 400 ml/day). Ten patients were on mechanical ventilation and 11 patients on vasopressor support. Mean treatment session time was 6.9 ± 1.8 hours. The mean pre-PDIRRT urea was 19.2 ± 6.9 mmol/L and the creatinine was 274 ± 116 μmol/L. The mean pre-PDIRRT lactate was 2.95 ± 2.24 mmol/L. Following treatment, all had significantly decreased to 13.2 ± 6.3 mmol/L, 215 ± 95 μmol/L and 2.25 ± 1.61 mmol/L, respectively (p=<0.0001, <0.0001, <0.05). Bicarbonate levels remained stable during treatment (23.0 ± 3.8 mmol/L to 23.1 ± 2.5 mmol/L). Mean norepinephrine dose changed from 8.8 ± 11.9 μg/min to 12.9 ± 27.0 μg/min after treatment (NS). There were no complications of therapy. Patient ICU survival was 71.4%.

Conclusions

PDIRRT with combined diffusive and convective clearance is an efficacious form of renal replacement, which can be safely and effectively conducted by ICU nurses following prescription by ICU physicians without any nephrological involvement and with adequate double filtration water purification.