Treatment of moderate to severe acute hypocalcemia in critically ill trauma patients

Higher Doses of Calcium Associated With Survival in Trauma Patients

INTRODUCTION

Calcium is required for coagulation, cardiac output, and peripheral vascular resistance. Between 85% and 94% of trauma patients treated with massive blood transfusion develop hypocalcemia.1 The aim of this study is to evaluate the relationship between increased intravenous calcium administration during massive transfusion and improved survival of trauma patients.

METHODS

We performed a retrospective analysis of trauma patients who received massive transfusion over a 2-y period. Doses of elemental calcium administered per unit of blood product transfused were calculated by calcium to blood product ratio (CBR). Chi-square test evaluated association between coagulopathy and 30-d mortality. Two-sample t-test evaluated association between CBR and coagulopathy. Bivariate regression analysis evaluated association between CBR and blood products transfused per patient. Multivariable logistic regression analysis, controlling for age, sex, coagulopathy, and Injury Severity Score evaluated the association between CBR and mortality.

RESULTS

The study included 77 patients. Coagulopathy was associated with increased 30-d mortality (P < 0.05). Patients who survived had higher CBR than those who died (P < 0.05). CBR was associated with a significant reduction in total blood products transfused per patient (P < 0.05). CBR was not associated with coagulopathy (P = 0.24). Multivariable logistic regression analysis demonstrated that Injury Severity Score ≥16, coagulopathy and decreased CBR were significant predictors of mortality (P < 0.05). CBR above 50 mg was a predictor of survival (P < 0.05).

CONCLUSIONS

Higher doses of calcium given per blood product transfused were associated with improved 30-d survival and decreased blood product transfusions.

American Association for the Surgery of Trauma/American College of Surgeons Committee on Trauma: Clinical protocol for damage-control resuscitation for the adult trauma patient

ABSTRACT

Damage-control resuscitation in the care of critically injured trauma patients aims to limit blood loss and prevent and treat coagulopathy by combining early definitive hemorrhage control, hypotensive resuscitation, and early and balanced use of blood products (hemostatic resuscitation) and the use of other hemostatic agents. This clinical protocol has been developed to provide evidence-based recommendations for optimal damage-control resuscitation in the care of trauma patients with hemorrhage.

Hypocalcemia in Trauma is Determined by the Number of Units Transfused, Not Whole Blood Versus Component Therapy

INTRODUCTION

Blood component resuscitation is associated with hypocalcemia (HC) (iCal <0.9 mmol/L) that contributes to coagulopathy and death in trauma patients. It is unknown whether or not whole blood (WB) resuscitation helps mitigate the risk of HC in trauma patients. We hypothesized that calcium homeostasis is maintained and mortality improved in patients who only receive WB.

MATERIALS AND METHODS

This is a retrospective review of all adult trauma patients who received WB from July 2018 to December 2020. Variables included transfusions, ionized calcium levels, and calcium replacement. Patients were characterized as follows based on blood products received: WB or WB with other blood components. Groups were compared with respect to HC, correction of HC, 24 h, and inpatient mortality.

RESULTS

Two hundred twenty-three patients received WB and met the inclusion criteria. 107 (48%) received WB only. HC occurred in 13% of patients who received more than one WB unit compared to 29% of WB and other blood component patients (P = 0.02). WB patients received less calcium replacement (median 250 mg versus 2000 mg, P < 0.01). HC and total units transfused within 4 h were associated with mortality in the adjusted model. HC significantly increased after 5 units of blood products were transfused, regardless of product type. WB was not protective against HC.

CONCLUSIONS

HC and failure to correct HC are significant risk factors for mortality in trauma. Resuscitations with WB only and WB in combination with other blood components are associated with HC especially when more than 5 units of any blood product are transfused. Calcium supplementation should be prioritized in any large volume transfusion, regardless of blood product type.

Risks in the Management of Polytrauma Patients: Clinical Insights

Polytrauma, a patient's condition with multiple injuries that involve multiple organs or systems, is the leading cause of mortality in young adults. Trauma-related injuries are a major public health concern due to their associated morbidity, high disability, associated death, and socioeconomic consequences. Management of polytrauma patients has evolved over the last few decades due to the development of trauma systems, improved pre-hospital assessment, transport and in-hospital care supported by complementary investigations. Recognising the mortality patterns in trauma has led to significant changes in the approach to managing these patients. A structured approach with application of advanced trauma life support (ATLS) algorithms and optimisation of care based on clinical and physiological parameters has led to the development of early appropriate care (EAC) guidelines to treat these patients, with subsequent improved outcomes in such patients. The journey of a polytrauma patient through the stages of pre-hospital care, emergency resuscitation, in-hospital stabilization and rehabilitation pathway can be associated with risks at any of these phases. We describe the various risks that can be anticipated during the management of polytrauma patients at different stages and provide clinical insights into early recognition and effective treatment of these to improve clinical outcomes.

Trauma-related electrolyte disturbances: From resuscitation to rhabdomyolysis

Traumatic injury results in drastic changes to a patient's normal physiology. The hormonal stress response, as well as some treatment strategies, lead to significant disruptions in electrolyte homeostasis that are important for clinicians to understand. In addition, advances in fluid resuscitation and modern transfusion practices have led to their own unique set of consequences, which we are just beginning to appreciate. Special attention is placed on rhabdomyolysis, as this distinct entity represents an extreme example of injury induced electrolyte derangements. This review describes the physiologic response to trauma and highlights some of the important electrolyte abnormalities that can be encountered while caring for the injured patient.

Augmented Renal Clearance Following Traumatic Injury in Critically Ill Patients Requiring Nutrition Therapy

The intent of this study was to ascertain the prevalence of augmented renal clearance (ARC) in patients with traumatic injuries who require nutrition therapy and identify factors associated with ARC. Adult patients admitted to the trauma intensive care unit from January 2015 to September 2016 who received enteral or parenteral nutrition therapy and had a 24 h urine collection within 4 to 14 days after injury were retrospectively evaluated. Patients with a serum creatinine concentration > 1.5 mg/dL, required dialysis, or had an incomplete urine collection were excluded. ARC was defined as a measured creatinine clearance > 149 mL/min/1.73 m². Two hundred and three patients were evaluated. One hundred and two (50%) exhibited ARC. A greater proportion of patients with ARC were male (86% vs. 67%; p = 0.004), had traumatic brain injury (33% vs. 9%; p = 0.001), a higher injury severity score (30 ± 11 vs. 26 ± 12; p = 0.015), were younger (36 ± 15 vs. 54 ± 17 years; p = 0.001), had a lower serum creatinine concentration (0.7 ± 2 vs. 0.9 ± 0.2 mg/dL; p = 0.001) and were more catabolic (nitrogen balance of −10.8 ± 13.0 vs. −6.2 ± 9.2 g/d; p = 0.004). The multivariate analysis revealed African American race and protein intake were also associated with ARC. Half of critically ill patients with traumatic injuries experience ARC. Patients with multiple risk factors for ARC should be closely evaluated for dosing of renally-eliminated electrolytes, nutrients, and medications.

Hypocalcemia in trauma patients: A systematic review

BACKGROUND

During hemorrhagic shock and subsequent resuscitation, pathways reliant upon calcium such as platelet function, intrinsic and extrinsic hemostasis, and cardiac contractility are disrupted. The objective of this systematic review was to examine current literature for associations between pretransfusion, admission ionized hypocalcemia, and composite outcomes including mortality, blood transfusion requirements, and coagulopathy in adult trauma patients.

METHODS

This review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. We searched Ovid MEDLINE and grey literature from database inception till May 3, 2020. Case series and reports were excluded. Reference lists of appraised studies were also screened for articles that the aforementioned databases might not have captured. The Newcastle-Ottawa Scale was used to assess study quality.

RESULTS

A total of 585 abstracts were screened through database searching and alternative sources. Six unique full-text studies were reviewed, of which three were excluded. Admission ionized hypocalcemia was present in up to 56.2% of the population in studies included in this review. Admission ionized hypocalcemia was also associated with increased mortality in all three studies, with increased blood transfusion requirements in two studies, and with coagulopathy in one study.

CONCLUSION

Hypocalcemia is a common finding in shocked trauma patients. While an association between admission ionized hypocalcemia and mortality, blood transfusion requirements, and coagulopathy has been identified, further prospective trials are essential to corroborating this association.

LEVEL OF EVIDENCE

Systematic review, level III.

Obesity attenuates serum 25-hydroxyvitamin D response to cholecalciferol therapy in critically ill patients

OBJECTIVES

The presence of obesity may confound cholecalciferol dosing in vitamin D-deficient patients owing to potentially decreased bioavailability. The aim of this retrospective study was to evaluate cholecalciferol therapy in vitamin D-deficient, critically ill trauma patients with and without obesity.

METHODS

Adult patients with severe traumatic injuries who had a serum 25-hydroxyvitamin D (25-OH vit D) <50nmol/L were prescribed 10 000 IU of liquid cholecalciferol daily. Efficacy was defined as achievement of a 25-OH vit D of 75 to 200nmol/L. Safety was evaluated by the presence of hypercalcemia (serum ionized calcium >1.32 mmol/L). Fifty-three patients (18 obese, 35 non-obese) were identified for study.

RESULTS

Despite similar baseline concentrations (36 ± 7 versus 37 ± 7 nmol/L; P = NS), 25-OH vit D response was attenuated for those with obesity after 1 and 2 wk of cholecalciferol therapy (51 ± 18 versus 66 ± 27nmol/L, P < 0.01; 68 ± 19 versus 92 ± 25nmol/L, P < 0.01, respectively). Patients with obesity also tended to experience less hypercalcemia (22% versus 49% of patients, respectively) post-cholecalciferol therapy.

CONCLUSION

Obesity alters the response to cholecalciferol therapy in critically ill patients with severe traumatic injuries.

Ionised calcium levels in major trauma patients who received blood en route to a military medical treatment facility

BACKGROUND

Hypocalcaemia is a common metabolic derangement in critically ill patients. Blood transfusion can also contribute to depleted calcium levels. The aims of this study were to identify the incidence of hypocalcaemia in military trauma patients receiving blood products en route to a deployed hospital facility and to determine if intravenous calcium, given during the prehospital phase, has an effect on admission calcium levels.

METHODS

This was a retrospective review of patients transported by the UK Medical Emergency Response Team in Afghanistan between January 2010 and December 2014 who were treated with blood products in the prehospital setting. Total units of blood products administered, basic demographics, Injury Severity Score and trauma type were collected. Ionised serum calcium levels on admission to hospital were compared between those who received blood products without prehospital intravenous calcium supplemental therapy (non-treatment) and patients who were treated with 10 mL of intravenous calcium chloride (10%) concurrently with blood products (treatment).

RESULTS

The study included 297 patients; 237 did not receive calcium and 60 did. The incidence of hypocalcaemia in the non-treatment group was 70.0% (n=166) compared with 28.3% (n=17) in the treatment group. Serum calcium levels were significantly different between the groups (1.03 mmol/L vs 1.25 mmol/L, difference 0.22 mmol/L, 95% CI 0.15 to 0.27). In the non-treatment group, 26.6% (n=63) had calcium levels within the normal range compared with 41.7% (n=25) in those who received calcium. There was a dose response of calcium level to blood products with a significant decrease in calcium levels as the volume of blood products increased.

CONCLUSION

Trauma patients who received blood products were at high risk of hypocalcaemia. Aggressive management of these patients with intravenous calcium during transfusion may be required.

Transient modulation of calcium and parathyroid hormone stimulates bone formation

Intermittent administration of parathyroid hormone can stimulate bone formation. Parathyroid hormone is a natural hormone that responds to serum calcium levels. In this study, we examined whether a transient increase and/or decrease in the serum calcium can stimulate bone formation. Using a mathematical model previously developed, we first predicted the effects of administration of parathyroid hormone, neutralizing parathyroid hormone antibody, calcium, and EGTA (calcium chelator) on the serum concentration of parathyroid hormone and calcium. The model predicted that intermittent injection of parathyroid hormone and ethylene glycol tetraacetic acid transiently elevated the serum parathyroid hormone, while that of parathyroid hormone antibody and calcium transiently reduced parathyroid hormone in the serum. In vitro analysis revealed that parathyroid hormone's transient changes (both up and down) elevated activating transcription factor 4-mediated osteocalcin expression. In the mouse model of osteoporosis, both intermittent administration of calcium and ethylene glycol tetraacetic acid showed tendency to increase bone mineral density of the upper limb (ulna and humerus) and spine, but the effects varied in a region-specific manner. Collectively, the study herein supports a common bone response to administration of calcium and its chelator through their effects on parathyroid hormone.

Hypocalcemia in trauma patients receiving massive transfusion

BACKGROUND

Massive transfusion protocol (MTP) is increasingly used in civilian trauma resuscitation. Calcium is vital for coagulation, but hypocalcemia commonly occurs during massive transfusion due to citrate and serum calcium chelation. This study was conducted to determine the incidence of hypocalcemia and severe hypocalcemia in trauma patients who receive massive transfusion and to compare characteristics of patients with severe versus nonsevere hypocalcemia.

MATERIALS AND METHODS

This was a retrospective study of trauma patients who received massive transfusion between January 2009 and November 2013. The primary outcome was the incidence of hypocalcemia (ionized calcium [iCa] < 1.12 mmol/L) and severe hypocalcemia (iCa < 0.90 mmol/L). Secondary outcomes included calcium monitoring, calcium replacement, and correction of coagulopathy.

RESULTS

There were 156 patients included; 152 (97%) experienced hypocalcemia, and 111 (71%) had severe hypocalcemia. Patients were stratified into iCa ≥ 0.90 (n = 45) and iCa < 0.90 (n = 111). There were no differences in demographics or baseline laboratories except the severe hypocalcemia group had higher baseline activated partial thromboplastin time (29.7 [23.7-50.9] versus 25.8 [22.3-35.9], P = 0.003), higher lactic acid (5.8 [4.1-9.8] versus 4.0 [3.1-7.8], P = 0.019), lower platelets (176 [108-237] versus 208 [169-272], P = 0.003), and lower pH (7.14 [6.98-7.28] versus 7.23 [7.14-7.33], P = 0.019). Mortality was higher in the severe hypocalcemia group (49% versus 24%, P = 0.007). Patients in the iCa < 0.90 group received more blood products (34 [23-58] versus 22 [18-30] units, P < 0.001), and calcium chloride (4 [2-7] versus 3 [1-4] g, P = 0.002), but there was no difference in duration of MTP or final iCa. Neither group reached a median iCa > 1.12.

CONCLUSIONS

Hypocalcemia is common during MTP, and vigilant monitoring is warranted. Research is needed to effectively manage hypocalcemia during massive transfusion.

Hypocalcemia as a prognostic factor in mortality and morbidity in moderate and severe traumatic brain injury

Objectives:

Our main objective was to evaluate whether serum hypocalcaemia (defined as <2.1 mmol/L [8.5 mg/dL]) and ionized serum calcium (defined as <1.10 mmol/L [4.5 mg/dL]) is a prognostic factor for mortality and morbidity (defined as Glasgow outcome score [GOS] ≤3) in early moderate and severe traumatic brain injury (TBI).

Materials and Methods:

We developed a retrospective study and evaluated clinical profiles from included patients from January 2004 to December 2012. Patients were between 16 and 87 years old and had a Glasgow coma scale of 3–13 points following TBI, with demonstrable intracranial lesions in cranial computed tomography.

Results:

We found a significant statistical difference (P < 0.008) in the ionized serum calcium levels on the 3^rd day of admission between the groups: GOS ≤3 and >3 (disability/death). According with the receiving operative curves analysis, we found that the best level of higher sensitivity (83.76%) and specificity (66.66%) of hypocalcaemia of serum ionized calcium on 3^rd day was the value of 1.11 mmol/L, with an odds ratio value of 6.45 (confidence intervals 95%: 2.02–20.55).

Conclusions:

The serum levels of ionized calcium on day 3 could be useful for the prediction of mortality and disability in patients with moderate and severe TBI.

Evaluation of an Intravenous Potassium Dosing Algorithm for Hypokalemic Critically Ill Patients

PURPOSE

The intent of this study was to evaluate the safety and efficacy of an intravenous (IV) potassium (K) dosing algorithm for hypokalemic critically ill trauma patients.

METHODS

Adult patients, admitted to the trauma intensive care unit from June 2010 to October 2012 and who received IV K therapy according to a standardized dosing algorithm, were retrospectively evaluated. Patients who received IV K during resuscitation or following initiation of nutrition therapy, IV fluids containing >20 mEq/L of potassium, or medications known to alter K homeostasis or those with an arterial pH change >0.1, diarrhea, hypomagnesemia, renal impairment, or morbid obesity were excluded.

RESULTS

In total, 715 patients were reviewed to obtain 100 evaluable patients. Serum K for patients with mild depletion (serum K, 3.5-3.9 mEq/L, n = 74) remained unchanged at 0.0 ± 0.3 mEq/L ( P = ns) following 46 ± 8 mEq. Serum K increased by 0.4 ± 0.3 mEq/L ( P = .001) following 78 ± 18 mEq during moderate depletion (serum K, 3-3.4 mEq/L). None of the patients experienced hyperkalemia (serum K, >5.2 mEq/L) postinfusion. The presence of traumatic brain injury (TBI) blunted the response to IV K for mild K depletion as only 26% had an increase in serum K compared with 55% of patients without TBI ( P = .025).

CONCLUSIONS

The Nutrition Support Service-guided IV K dosing algorithm was safe for patients with mild and moderate hypokalemia and efficacious for those with moderate hypokalemia. Further study in patients with severe hypokalemia (serum K, <3 mEq/L) is warranted.

Phosphorus and calcium: a review for the adult nutrition support clinician

Phosphorus (P) and calcium (Ca) serve vital roles in the human body and are essential components of nutrition support therapy. Regulation of P and regulation of Ca in the body are closely interrelated, and P and Ca homeostasis can be affected by several factors, including disease states, clinical condition, severity of illness, and medications. Nutrition support clinicians must understand these factors to prevent and treat P and Ca disorders in patients receiving nutrition support therapy. This review provides an overview of P and Ca for the adult nutrition support clinician, with some emphasis on the hospitalized inpatient.

Hypocalcaemia as a prognostic factor of early mortality in moderate and severe traumatic brain injury

OBJECTIVES

Our main objective was to evaluate whether serum hypocalcaemia on the third day [defined as < 2.1 mmol/l (8.5 mg/dl)] is a prognostic factor for early mortality after moderate and severe traumatic brain injury (TBI).

METHODS

We developed an ambispective comparative case control study. We evaluated clinical profiles from included patients from January 2005 to July 2009 and we prospectively recruited additional patients from August 2009 to July 2011. Patients were between 1 and 89 years old and had a Glasgow Coma Scale of 3-12 points following TBI.

RESULTS

We calculated an Odds Ratio of 5.2 (Confidence Intervals 95%: 4.48 to 6.032) for hypocalcaemia on day three, which was associated with death. Retrospectively (January 2005 to July 2009) we compiled data from 81 patients. Prospectively (August 2009 to July 2011) we recruited 41 patients. The adjusted variables in the logistic regression final model were: serum calcium on day three (Odds Ratio 3.5, Confidence Intervals 95%: 1·12 to 13·61, P < 0·028) and anisocoria (Odds Ratio 8·24, Confidence Intervals 95%: 1·3 to 67·35, P < 0·019) obtaining an adjusted R2 of 0·22 (P < 0·005).

DISCUSSION

The serum levels of calcium on day three could be useful for the prediction of mortality in patients with moderate and severe TBI.

Evaluation of an electrolyte repletion protocol for cardiac surgery intensive care patients

BACKGROUND

Implementation of electrolyte repletion protocols to facilitate and ensure the safety of electrolyte control is common practice in intensive care units (ICUs). However, few protocols have been evaluated and validated.

OBJECTIVE

To evaluate the effectiveness and safety of an electrolyte repletion protocol in a large, homogeneous group of postoperative patients.

METHODS

A retrospective study of patients admitted to the surgical ICU following coronary artery bypass grafting or heart valve replacement was undertaken at the Centre hospitalier universitaire de Sherbrooke, a 682-bed tertiary care hospital in Sherbrooke, Quebec. The proportion of measured values for serum potassium concentration that were within the desired range was compared between patients treated according to the electrolyte repletion protocol and those treated with the traditional approach to electrolyte repletion. Management of magnesium, phosphorus, and ionized calcium balance was also compared. The incidence of cardiac arrhythmias was documented, and the safety of the electrolyte repletion protocol was evaluated by determining and comparing proportions of values for serum electrolyte concentration that were above the desired range.

RESULTS

In total, 627 patients were included in the study: 312 in the control group and 315 in the protocol group. The proportion of patients with 100% of morning values for serum potassium concentration within the normal range was significantly higher in the protocol group than in the control group (66.1% versus 56.8%; p = 0.018). In the protocol group, significantly more patients received one or more replacement doses of magnesium and phosphorus (p < 0.001). The proportions of serum electrolyte values above the normal range were similar between the 2 groups, and there was no difference in the incidence of cardiac arrhythmias.

CONCLUSIONS

The electrolyte repletion protocol was more efficacious than traditional electrolyte repletion in maintaining normal serum potassium concentration and was safe.

Influence of traumatic brain injury on potassium and phosphorus homeostasis in critically ill multiple trauma patients

OBJECTIVE

The intent of this study was to ascertain whether multiple trauma patients with traumatic brain injury (TBI) had lower serum concentrations of potassium and phosphorus and required more aggressive supplementation than multiple trauma patients without TBI.

METHODS

Ventilator-dependent adult patients without renal impairment who were admitted to the trauma intensive care unit or neurosurgical intensive care unit and who received enteral nutrition were evaluated for the first 14 d after hospital admission. Patients were grouped according to the presence or absence of TBI. Target serum concentrations for potassium and phosphorus were 4 mEq/L and 4 mg/dL, respectively. Electrolyte repletion therapy was given according to the nutritional support service guidelines.

RESULTS

Fifty trauma patients (25 with and without TBI) were studied. Daily serum potassium concentrations were consistently lower for those with TBI (P < or = 0.001), whereas the mean net potassium intake was greater (1.3 +/- 0.5 versus 0.7 +/- 0.3 mEq x kg(-1) x d(-1), respectively, P < or = 0.001). Serial serum phosphorus concentrations were similar between groups (P = NS) except for a significantly lower serum phosphorus concentration for trauma patients with TBI on day 3 after hospital admission (2.5 +/- 0.5 versus 2.9 +/- 0.7 mg/dL, respectively, P < or = 0.05). However, the mean net phosphorus intake was significantly greater for trauma patients with TBI (0.65 +/- 0.25 versus 0.45 +/- 0.17 mmol x kg(-1) x d(-1), P < or = 0.001).

CONCLUSION

Potassium and phosphorus requirements are greater for multiple trauma patients with TBI compared with those without TBI.

Dose-dependent characteristics of intravenous calcium therapy for hypocalcemic critically ill trauma patients receiving specialized nutritional support

OBJECTIVE

The purpose of this investigation was to evaluate the dose-dependent characteristics of intravenous calcium gluconate therapy for hypocalcemic critically ill patients.

METHODS

The dose-dependent characteristics of 2 g versus 4 g of intravenous calcium gluconate therapy were evaluated in 25 critically ill, adult multiple trauma patients with hypocalcemia. The calcium gluconate was infused at a rate of 1 g/h for both groups. Patients weighed within 90% to 120% of ideal body weight, had normal renal function, did not receive diuretic therapy, and did not have anasarca.

RESULTS

Fifteen patients with mild hypocalcemia (serum ionized calcium concentration [iCa] 1-1.12 mmol/L) were given 2 g of calcium gluconate. Ten patients with moderate to severe hypocalcemia (iCa <1 mmol/L) were given 4 g. Each dosage group had a significant (P < or = 0.001) increase in iCa (from 1.07 +/- 0.05 to 1.17 +/- 0.05 mmol/L and from 0.92 +/- 0.08 to 1.16 +/- 0.11 mmol/L, respectively). Each dosage group retained about half of the dose in the exchangeable calcium space (P = NS between groups), but the higher dosage group retained significantly more elemental calcium overall (81 +/- 38 versus 201 +/- 50 mg, respectively, P < or = 001). Serum ionized calcium concentrations achieved a plateau without a further decline in iCa by 10 h after completion of the infusion for each dosage.

CONCLUSION

About half of the administered elemental calcium dose was retained for each dosage group, with the higher dose (4 g) resulting in significantly more elemental calcium retention in the exchangeable calcium space. An iCa determination performed about > or =10 h after the completion of the calcium gluconate infusion should be sufficient time to ensure equilibration of iCa to assess the efficacy of the therapy. This mode of calcium therapy serves as an effective means for providing calcium to the acutely hypocalcemic, critically ill, multiple trauma patient.