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BACKGROUND: Metabolic acidosis is a major complication of critical illness. However, its current epidemiology and its treatment with sodium bicarbonate given to correct metabolic acidosis in the ICU are poorly understood. METHOD(S): This was an international retrospective observational study in 18 ICUs in Australia, Japan, and Taiwan. Adult patients were consecutively screened, and those with early metabolic acidosis (pH<7.3 and a Base Excess<-4 mEq/L, within 24-h of ICU admission) were included. Screening continued until 10 patients who received and 10 patients who did not receive sodium bicarbonate in the first 24 h (early bicarbonate therapy) were included at each site. The primary outcome was ICU mortality, and the association between sodium bicarbonate and the clinical outcomes were assessed using regression analysis with generalized linear mixed model. RESULT(S): We screened 9437 patients. Of these, 1292 had early metabolic acidosis (14.0%). Early sodium bicarbonate was given to 18.0% (233/1292) of these patients. Dosing, physiological, and clinical outcome data were assessed in 360 patients. The median dose of sodium bicarbonate in the first 24 h was 110 mmol, which was not correlated with bodyweight or the severity of metabolic acidosis. Patients who received early sodium bicarbonate had higher APACHE III scores, lower pH, lower base excess, lower PaCO2, and a higher lactate and received higher doses of vasopressors. After adjusting for confounders, the early administration of sodium bicarbonate was associated with an adjusted odds ratio (aOR) of 0.85 (95% CI, 0.44 to 1.62) for ICU mortality. In patients with vasopressor dependency, early sodium bicarbonate was associated with higher mean arterial pressure at 6 h and an aOR of 0.52 (95% CI, 0.22 to 1.19) for ICU mortality. CONCLUSION(S): Early metabolic acidosis is common in critically ill patients. Early sodium bicarbonate is administered by clinicians to more severely ill patients but without correction fo

Background: Metabolic acidosis is a major complication of critical illness. However, its current epidemiology and its treatment with sodium bicarbonate given to correct metabolic acidosis in the ICU are poorly understood. Method(s): This was an international retrospective observational study in 18 ICUs in Australia, Japan, and Taiwan. Adult patients were consecutively screened, and those with early metabolic acidosis (pH < 7.3 and a Base Excess < -4 mEq/L, within 24-h of ICU admission) were included. Screening continued until 10 patients who received and 10 patients who did not receive sodium bicarbonate in the first 24 h (early bicarbonate therapy) were included at each site. The primary outcome was ICU mortality, and the association between sodium bicarbonate and the clinical outcomes were assessed using regression analysis with generalized linear mixed model. Result(s): We screened 9437 patients. Of these, 1292 had early metabolic acidosis (14.0%). Early sodium bicarbonate was given to 18.0% (233/1292) of these patients. Dosing, physiological, and clinical outcome data were assessed in 360 patients. The median dose of sodium bicarbonate in the first 24 h was 110 mmol, which was not correlated with bodyweight or the severity of metabolic acidosis. Patients who received early sodium bicarbonate had higher APACHE III scores, lower pH, lower base excess, lower PaCO2, and a higher lactate and received higher doses of vasopressors. After adjusting for confounders, the early administration of sodium bicarbonate was associated with an adjusted odds ratio (aOR) of 0.85 (95% CI, 0.44 to 1.62) for ICU mortality. In patients with vasopressor dependency, early sodium bicarbonate was associated with higher mean arterial pressure at 6 h and an aOR of 0.52 (95% CI, 0.22 to 1.19) for ICU mortality. Conclusion(s): Early metabolic acidosis is common in critically ill patients. Early sodium bicarbonate is administered by clinicians to more severely ill patients but without correctio

BACKGROUND: Metabolic acidosis is a major complication of critical illness. However, its current epidemiology and its treatment with sodium bicarbonate given to correct metabolic acidosis in the ICU are poorly understood. METHOD: This was an international retrospective observational study in 18 ICUs in Australia, Japan, and Taiwan. Adult patients were consecutively screened, and those with early metabolic acidosis (pH < 7.3 and a Base Excess < -4 mEq/L, within 24-h of ICU admission) were included. Screening continued until 10 patients who received and 10 patients who did not receive sodium bicarbonate in the first 24 h (early bicarbonate therapy) were included at each site. The primary outcome was ICU mortality, and the association between sodium bicarbonate and the clinical outcomes were assessed using regression analysis with generalized linear mixed model. RESULTS: We screened 9437 patients. Of these, 1292 had early metabolic acidosis (14.0%). Early sodium bicarbonate was given to 18.0% (233/1292) of these patients. Dosing, physiological, and clinical outcome data were assessed in 360 patients. The median dose of sodium bicarbonate in the first 24 h was 110 mmol, which was not correlated with bodyweight or the severity of metabolic acidosis. Patients who received early sodium bicarbonate had higher APACHE III scores, lower pH, lower base excess, lower PaCO2, and a higher lactate and received higher doses of vasopressors. After adjusting for confounders, the early administration of sodium bicarbonate was associated with an adjusted odds ratio (aOR) of 0.85 (95% CI, 0.44 to 1.62) for ICU mortality. In patients with vasopressor dependency, early sodium bicarbonate was associated with higher mean arterial pressure at 6 h and an aOR of 0.52 (95% CI, 0.22 to 1.19) for ICU mortality. CONCLUSIONS: Early metabolic acidosis is common in critically ill patients. Early sodium bicarbonate is administered by clinicians to more severely ill patients but without correction for w

Importance: It is unclear whether vitamin C, hydrocortisone, and thiamine are more effective than hydrocortisone alone in expediting resolution of septic shock. Objective(s): To determine whether the combination of vitamin C, hydrocortisone, and thiamine, compared with hydrocortisone alone, improves the duration of time alive and free of vasopressor administration in patients with septic shock. Design, Setting, and Participant(s): Multicenter, open-label, randomized clinical trial conducted in 10 intensive care units in Australia, New Zealand, and Brazil that recruited 216 patients fulfilling the Sepsis-3 definition of septic shock. The first patient was enrolled on May 8, 2018, and the last on July 9, 2019. The final date of follow-up was October 6, 2019. Intervention(s): Patients were randomized to the intervention group (n = 109), consisting of intravenous vitamin C (1.5 g every 6 hours), hydrocortisone (50 mg every 6 hours), and thiamine (200 mg every 12 hours), or to the control group (n = 107), consisting of intravenous hydrocortisone (50 mg every 6 hours) alone until shock resolution or up to 10 days. Main Outcomes and Measures: The primary trial outcome was duration of time alive and free of vasopressor administration up to day 7. Ten secondary outcomes were prespecified, including 90-day mortality. Result(s): Among 216 patients who were randomized, 211 provided consent and completed the primary outcome measurement (mean age, 61.7 years [SD, 15.0]; 133 men [63%]). Time alive and vasopressor free up to day 7 was 122.1 hours (interquartile range [IQR], 76.3-145.4 hours) in the intervention group and 124.6 hours (IQR, 82.1-147.0 hours) in the control group; the median of all paired differences was-0.6 hours (95% CI,-8.3 to 7.2 hours; P =.83). Of 10 prespecified secondary outcomes, 9 showed no statistically significant difference. Ninety-day mortality was 30/105 (28.6%) in the intervention group and 25/102 (24.5%) in the control group (hazard ratio, 1.18; 95% CI

IMPORTANCE: It is unclear whether vitamin C, hydrocortisone, and thiamine are more effective than hydrocortisone alone in expediting resolution of septic shock. OBJECTIVE: To determine whether the combination of vitamin C, hydrocortisone, and thiamine, compared with hydrocortisone alone, improves the duration of time alive and free of vasopressor administration in patients with septic shock. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, open-label, randomized clinical trial conducted in 10 intensive care units in Australia, New Zealand, and Brazil that recruited 216 patients fulfilling the Sepsis-3 definition of septic shock. The first patient was enrolled on May 8, 2018, and the last on July 9, 2019. The final date of follow-up was October 6, 2019. INTERVENTIONS: Patients were randomized to the intervention group (n = 109), consisting of intravenous vitamin C (1.5 g every 6 hours), hydrocortisone (50 mg every 6 hours), and thiamine (200 mg every 12 hours), or to the control group (n = 107), consisting of intravenous hydrocortisone (50 mg every 6 hours) alone until shock resolution or up to 10 days. MAIN OUTCOMES AND MEASURES: The primary trial outcome was duration of time alive and free of vasopressor administration up to day 7. Ten secondary outcomes were prespecified, including 90-day mortality. RESULTS: Among 216 patients who were randomized, 211 provided consent and completed the primary outcome measurement (mean age, 61.7 years [SD, 15.0]; 133 men [63%]). Time alive and vasopressor free up to day 7 was 122.1 hours (interquartile range [IQR], 76.3-145.4 hours) in the intervention group and 124.6 hours (IQR, 82.1-147.0 hours) in the control group; the median of all paired differences was -0.6 hours (95% CI, -8.3 to 7.2 hours; P = .83). Of 10 prespecified secondary outcomes, 9 showed no statistically significant difference. Ninety-day mortality was 30/105 (28.6%) in the intervention group and 25/102 (24.5%) in the control group (hazard ratio, 1.18; 95% CI, 0.69

The Lucky Friday Mine in Idaho utilises paste backfill in a combination of overhand and underhand longwall cut-and-fill stopes. A fine particle content of 15% or more in the tailings sand fraction used in the fill is necessary to form a lubricating layer on which backfill slugs can travel in the pipelines. The use of cement admixtures to reduce backfill binder concentrations and to reduce the occurrence of cold joints in the fill has been evaluated. The addition of Pozzolith 344N, amongst other admixture combinations, resulted in an increase in compressive strength and allowed binder content to be reduced by 20% whilst enhancing flowability to an extent that gave the possibility of reducing water content to achieve further strength improvements. The tendency for cold joint formation was also reduced when initial set times were retarded and flow characteristics improved., The Lucky Friday Mine in Idaho utilises paste backfill in a combination of overhand and underhand longwall cut-and-fill stopes. A fine particle content of 15% or more in the tailings sand fraction used in the fill is necessary to form a lubricating layer on which backfill slugs can travel in the pipelines. The use of cement admixtures to reduce backfill binder concentrations and to reduce the occurrence of cold joints in the fill has been evaluated. The addition of Pozzolith 344N, amongst other admixture combinations, resulted in an increase in compressive strength and allowed binder content to be reduced by 20% whilst enhancing flowability to an extent that gave the possibility of reducing water content to achieve further strength improvements. The tendency for cold joint formation was also reduced when initial set times were retarded and flow characteristics improved.

Hecla Mining and NIOSH have carried out a study at the Lucky Friday mine in Idaho to assess the safety of rock support supplied by reinforced cemented paste backfill. Laboratory data are presented on the backfill modulus values and are compared with mine data indicating that wall closure caused deformation of the backfill and induced loads in the vertical Diwydag bolts used as backfill reinforcement. An interpretation of the interactions between wall closure, fill deformation and induced loads in the backfill bolts is presented. It is suggested that a compressive zone is created in the backfill between the upper and lower bearing plates on the reinforcing bolts, and that the backfill remains stable as long as the compressive zones from adjacent zones interact., Hecla Mining and NIOSH have carried out a study at the Lucky Friday mine in Idaho to assess the safety of rock support supplied by reinforced cemented paste backfill. Laboratory data are presented on the backfill modulus values and are compared with mine data indicating that wall closure caused deformation of the backfill and induced loads in the vertical Diwydag bolts used as backfill reinforcement. An interpretation of the interactions between wall closure, fill deformation and induced loads in the backfill bolts is presented. It is suggested that a compressive zone is created in the backfill between the upper and lower bearing plates on the reinforcing bolts, and that the backfill remains stable as long as the compressive zones from adjacent zones interact.

The Lucky Friday vein in Idaho has produced over 7 000 000 tonnes of ore averaging 533 g/t Ag, 10.68% Pb and 1.35% Zn. Access from the Silver shaft is via ramps . Sublevels are developed in the vein at 27 m vertical intervals, each allowing mining of eight 3.3 m high cuts by underhand cut and fill. The system depends on cemented fill of consistent quality: sand is prepared from zinc flotation tailings and mixed to a paste with computer-controlled amounts of water and cement. Batches are pumped underground through a 15 cm pipe in the shaft and 10 cm pipes on the level. Mine services, rock mechanics and stope development are described and details are given of the backfilling system. Direct and indirect operating costs are listed., The Lucky Friday vein in Idaho has produced over 7 000 000 tonnes of ore averaging 533 g/t Ag, 10.68% Pb and 1.35% Zn. Access from the Silver shaft is via ramps . Sublevels are developed in the vein at 27 m vertical intervals, each allowing mining of eight 3.3 m high cuts by underhand cut and fill. The system depends on cemented fill of consistent quality: sand is prepared from zinc flotation tailings and mixed to a paste with computer-controlled amounts of water and cement. Batches are pumped underground through a 15 cm pipe in the shaft and 10 cm pipes on the level. Mine services, rock mechanics and stope development are described and details are given of the backfilling system. Direct and indirect operating costs are listed.