Hoi-Ping Shum

Interaction between fluid balance and disease severity on patient outcome in the critically ill

PURPOSE There is evidence in literature regarding the benefits of immediate aggressive fluid resuscitation together with conservative fluid management approach after initial stabilization. This retrospective study assesses the relationship between fluid balance during intensive care unit (ICU) stay and outcomes among general critically ill patients. In addition, we also aim to see the effect of fluid gain among patients with different disease severity. METHODS A total of 639 patients admitted into ICU who stayed for 3 days or more were evaluated. Fluid balances during ICU stay were recorded. A logistic regression analysis was performed to identify significant factors associated with hospital mortality. RESULTS Acute Physiology and Chronic Health Evaluation IV predicted risk of death, fluid balance on the second plus third ICU days, and total fluid balance during ICU stay were positively associated with hospital death. Significant positive fluid balance on first ICU day, in contrast, was negatively associated with hospital mortality. The positive correlation between standardized mortality ratio (Acute Physiology and Chronic Health Evaluation IV) and fluid gain on the second plus third ICU days increases with disease severity. CONCLUSION Early adequate fluid resuscitation together with conservative late fluid management may provide better patient outcomes. The effect of fluid management strategy on patient outcome may depend on the underlying disease severity.

Regional citrate anticoagulation in predilution continuous venovenous hemofiltration using prismocitrate 10/2 solution.

Regional citrate anticoagulation (RCA) for continuous renal replacement therapy (CRRT) is associated with a longer filter life and fewer bleeding events. Complexity of the regimen is the major hurdle preventing widespread application. This study describes a simple predilution continuous venovenous hemofiltration (CVVH) protocol utilizing a commercially prepared replacement solution containing citrate (Prismocitrate 10/2). Ten patients with acute renal failure were evaluated. The Prismaflex system was used for predilution CVVH, with Prismocitrate 10/2 running at 2500 mL/h as the main predilution replacement. An 8.4% sodium bicarbonate solution was infused at 50 mL/h in the first 2 h followed by 30 mL/h; 10% calcium gluconate was given to achieve an ionized calcium (iCa) level of 1–1.2 mmol/L. The circuit was run for 72 h unless there was filter clotting, transportation was required, or the patient did not require further CRRT. Total treatment duration was 504.5 h. The post‐dilution equivalent ultrafiltration rate was 32.9 mL/kg/h (interquartile range [IQR] 31.6–38.2) and the median circuit life was 50.3 h (IQR 25.5–72.0). None of the circuit was changed due to circuit clotting. The median systemic iCa was 0.98 mmol/L (IQR 0.91–1.08). The total calcium‐to‐iCa ratio was 2.33 (IQR 2.21–2.45). None of the patients developed hypernatremia (Na ≥ 150 mmol/L) or citrate toxicity (total Ca‐to‐iCa ratio > 2.5 plus increasing metabolic acidosis), and metabolic alkalosis (pH ≥ 7.5) occurred in one patient. This simple RCA CVVH protocol using commercially‐prepared solution could be a feasible, relatively safe, and effective alternative to the conventional regimen for patients with a body weight up to 80 kg.

Recent knowledge on the pathophysiology of septic acute kidney injury: A narrative review.

Sepsis is the commonest cause of acute kidney injury in critically ill patients. Its pathophysiology is complex and not well understood. Until recently, it was believed that kidney hypoperfusion is the major contributor of septic acute kidney injury. However, recent publications have improved our understanding on this topic. We now know that its mechanisms included the following: (1) renal macrocirculatory and microcirculatory disturbance, (2) surge of inflammatory markers and oxidative stress, (3) coagulation cascade activation, and (4) bioenergetics adaptive response with controlled cell-cycle arrest aiming to prevent cell death. Uncovering these complicated mechanisms may facilitate the development of more appropriate therapeutic measures in the future.

A Retrospective Review of the Use of Regional Citrate Anticoagulation in Continuous Venovenous Hemofiltration for Critically Ill Patients

Background. The emergence of a commercially prepared citrate solution has revolutionized the use of RCA in the intensive care unit (ICU). The aim of this study was to evaluate the safety profile of a commercially prepared citrate solution. Method. Predilution continuous venovenous hemofiltration (CVVH) was performed using Prismocitrate 10/2 at 2500 mL/h and a blood flow rate of 150 mL/min. Calcium chloride solution was infused to maintain ionized calcium within 1.0–1.2 mmol/L. An 8.4% sodium bicarbonate solution was infused separately. Treatment was stopped when the predefined clinical target was reached or the filter clotted. Result. 58 sessions of citrate RCA were analyzed. The median circuit lifetime was 26.0 h (interquartile range IQR 21.2–44.3). The percentage of circuits lasting more than 12 h, 24 h, and 48 h was 94.6%, 58.9%, and 16.1%, respectively. There was no incidence of hypernatremia and median pH was <7.5. Hypomagnesemia and hypophosphatemia were detected in 41.6% and 17.6% of blood samples taken, respectively. Although 16 episodes had a total calcium/ionized calcium (total Ca/iCa) >2.5, only four patients had evidence of citrate accumulation. Conclusion. The commercially prepared citrate solution could be used safely in critically ill patients who required CVVH with no major adverse events.

Septic acute kidney injury in critically ill patients – a single-center study on its incidence, clinical characteristics, and outcome predictors

Abstract Purpose The objective of this study is to examine the incidence, clinical characteristics, and outcome (90-day mortality) of critically ill Chinese patients with septic AKI. Methods Patients admitted to the ICU of a regional hospital from 1 January 2011 to 31 December 2013 were included, excluding those on chronic renal replacement therapy. AKI was defined using KDIGO criteria. Patients were followed till 90 days from ICU admission or death, whichever occurred earlier. Demographics, diagnosis, clinical characteristics, and outcome were analyzed. Results In total, 3687 patients were included and 54.7% patients developed AKI. Sepsis was the most common cause of AKI (49.2%). Compared to those without AKI, AKI patients had higher disease severity, more physiological and biochemical disturbance, and carried significant co-morbidities. Ninety-day mortality increased with severity of AKI (16.7, 27.5, and 48.3% for KDIGO stage 1, 2, and 3 AKI, p < 0.001). Full renal recovery was achieved in 71.6% of AKI patients. Compared with non-septic AKI, septic AKI was associated with higher disease severity and required more aggressive support. Non-recovery of renal function occurred in 2.5% of patients with septic AKI, compared with 6.4% in non-septic AKI (p < 0.001). Cox regression analysis showed that age, emergency ICU admission, post-operative cases, admission diagnosis, etiology of AKI, disease severity score, mechanical ventilation, vasopressor support, and blood parameters (like albumin, potassium and pH) independently predicted 90-day mortality. Conclusions AKI, especially septic AKI is common in critically ill Chinese patients and is associated with poor patient outcome. Etiology of AKI has a significant impact on 90-day mortality and may affect renal outcome.

Clinical Outcomes of Extended Versus Intermittent Infusion of Piperacillin/Tazobactam in Critically Ill Patients: A Prospective Clinical Trial

To determine whether critically ill patients receiving extended‐infusion (EI) piperacillin/tazobactam would have improved clinical outcomes compared with patients receiving intermittent infusions.

The use of regional citrate anticoagulation continuous venovenous hemofiltration in extracorporeal membrane oxygenation.

Patients on extracorporeal membrane oxygenation (ECMO) frequently requires continuous renal replacement therapy (CRRT). Additional anticoagulation for the CRRT circuit is usually not employed, but this may increases the risk of clot embolization, which shortens oxygenator lifespan and increases patient’s risk. We report our experience on the use of regional citrate anticoagulation continuous venovenous hemofiltration (RCA-CVVH) connected to an ECMO circuit, which could be useful during low heparin or heparin-free ECMO situations. Regional citrate anticoagulation continuous venovenous hemofiltration was performed using AK200US machine with a blood flow of 150 ml/min, Acid Citrate Dextrose Solution prefilter infusion at 240 ml/hr, ultrafiltration rate of 2,040 ml/hr, and postdilutional online generated replacement fluid infused as appropriate. The circuit was aimed to run for 30 hrs. From May 2009 to May 2013, 63 patients received ECMO and 29 received RCA-CVVH. The median total CVVH time was 131 hrs (interquartile range [IQR]: 61–224 hrs), and hemofilter life was 27.2 hrs (IQR: 25.7–28.5 hrs). No hemofilter or oxygenator was changed because of clotting. Their hospital mortality was 27.6%. There were eight patients, who were judged to be too sick for anticoagulation, received predilution CRRT during the same period. Their hospital mortality was 75%. In conclusion, online postdilutional RCA-CVVH connected to an ECMO circuit is a feasible, safe, and effective CRRT technique.

Outcome of elderly patients who receive intensive care at a regional hospital in Hong Kong.

OBJECTIVE To evaluate the clinical outcome (180-day mortality) of very elderly critically ill patients (age ≥80 years) and compare with those aged 60 to 79 years. DESIGN Historical cohort study. SETTING Regional hospital, Hong Kong. PATIENTS Patients aged ≥60 years admitted between 1 January 2009 and 31 December 2013 to the Intensive Care Unit of the hospital. RESULTS Over 5 years, 4226 patients aged ≥60 years were admitted (55.5% total intensive care unit admissions), of whom 32.8% were aged ≥80 years. The proportion of patients aged ≥80 years increased over 5 years. As expected, those aged ≥80 years carried more significant co-morbidities and a higher disease severity compared with those aged 60 to 79 years. They required more mechanical ventilatory support, were less likely to receive renal replacement therapy, and had a higher intensive care unit/hospital/180-day mortality compared with those aged 60 to 79 years. Nonetheless, 71.8% were discharged home and 62.2% survived >180 days following intensive care unit admission. Cox regression analysis revealed that Acute Physiology and Chronic Health Evaluation IV-minus-Age score, emergency admission, intensive care unit admission due to cardiovascular problem, neurosurgical cases, presence of significant co-morbidities (diabetes mellitus, metastatic carcinoma, leukaemia, or myeloma), and requirement for mechanical ventilation independently predicted 180-day mortality. CONCLUSIONS The proportion of critically ill patients aged ≥80 years increased over a 5-year period. Despite having more significant co-morbidities, greater disease severity, and higher intensive care unit/hospital/180-day mortality rate compared with those aged 60 to 79 years, 71.8% of those ≥80 years could be discharged home and 62.2% survived >180 days following intensive care unit admission. Disease severity, presence of co-morbidities, requirement for mechanical ventilation, emergency cases, and admission diagnosis independently predicted 180-day mortality.

Predictive value of plasma neutrophil gelatinase‐associated lipocalin for acute kidney injury in intensive care unit patients after major non‐cardiac surgery

The performance of plasma neutrophil gelatinase‐associated lipocalin (pNGAL) for prediction of acute kidney injury (AKI) in non‐cardiac surgical patients has not been well described. This study investigates the use of pNGAL for early detection of AKI in patients admitted to an intensive care unit (ICU) after major or ultra‐major non‐cardiac surgery.

The aquarium in the right heart

We presented a case with massive hepatic portovenous gas (HPVG) and gastric emphysema, probably due to increased intraluminal pressure in the stomach after bagging and noninvasive ventilation. There are multiple microbubbles in the inferior vena cava, right atrium and right ventricle. There has been only one case report ever published showing the similar features of the “aquarium sign” in the right heart in a patient with intussusception. We believe our case is a good illustration of this extremely rare entity in echocardiography.