Prevention Of Hypocalcemia Research Articles

Prevention of hypocalcemia and hypoparathyroidism after total thyroidectomy. Recommendations of the Francophone Association of Endocrine Surgery (AFCE) with the French Society of Endocrinology (SFE) and the French Society of Nuclear Medicine (SFMN).

Postoperative hypoparathyroidism, resulting from removal and/or devascularization of one or more parathyroid glands, is a feared complication of total thyroidectomy. Two forms, which are distinguished by their frequency, their time to onset and their duration as well as by their presentation, must be individualized: early postoperative hypocalcemia, often secondary to early hypoparathyroidism is a frequent and often transient situation occurring within the first days after surgery; permanent hypoparathyroidism, which is rarer, manifests when parathyroid function remains impaired for more than six months after surgery. Because of their severity, these conditions must be known and ideally prevented during total thyroidectomy. The objective of this article is to provide surgeons with practical recommendations for the prevention, diagnosis, and treatment of hypoparathyroidism after total thyroidectomy. These recommendations, which are the fruit of a medico-surgical consensus, were developed by the Francophone Association of Endocrine Surgery (AFCE), the French Society of Endocrinology (SFE) and the French Society of Nuclear Medicine and Molecular Imaging. (SFMN). The content, grade and level of evidence for each recommendation was decided after consultation within a panel of experts, based on an analysis of recent literature.

Potential of a rumen bolus containing 1,25-dihydroxyvitamin D3 glycosides for the prevention of hypocalcaemia in primiparous and multiparous dairy cows

Periparturient hypocalcaemia is a widespread metabolic disorder in dairy cows. Clinical and subclinical cases occur primarily in multiparous (Multi) cows, but subclinical cases have also been reported in primiparous (Primi) cows. A preventive strategy was investigated by administering the physiologically active vitamin D3 metabolite, 1,25-dihydroxyvitamin D3 (1,25-dihydroxycholecalciferol, 1,25(OH)2D3) as a rumen bolus. The bolus contained tablets of 1,25(OH)2D3 glycoside extract from Solanum glaucophyllum (SGE), releasing SGE over several days. The aim was to study the effect of a bolus containing 0 (C) or 500 µg (SGE) of 1,25(OH)2D3 on 1,25(OH)2D3 and mineral status in periparturient cows up to three weeks into lactation and on colostrum, milk and calves’ blood mineral contents. The bolus was administered three to four days prior to expected calving to Primi and Multi cows fed a herbage-based diet (dietary cation-anion difference of +522 mEq/kg DM). One C or SGE bolus was applied to 12 Primi and 12 Multi cows. Blood was regularly sampled (and selected a posteriori for antepartum samples) in regard to the actual calving day (d0), immediately prior to bolus application and at day −2, 0.5, 1, 1.5, 2, 4, 8, 11, 15, 18 and 22. Additional samples included urine (at bolus application, d0.5 and d2), colostrum, milk samples (weekly) and calves’ blood (d2). Blood serum 1,25(OH)2D3 increased between d0.5 and d2 in Primi-SGE, but remained unchanged in Primi-C, as did parathyroid hormone (PTH) and Ca in all Primi. Urinary Ca of Primi-SGE was increased on d2, indicating regulation of Ca excess. Three Multi-C cows with confirmed clinical hypocalcaemia needed treatment and thus were excluded from the dataset and replaced. Blood serum 1,25(OH)2D3 and PTH increased while Ca dropped by 40% between d0.5 and d2 in Multi-C, whereas 1,25(OH)2D3, Ca and PTH remained unchanged in Multi-SGE. Blood serum carboxyterminal telopeptide of type I collagen was higher in Primi than in Multi and increased with time, except in Primi-C. Mineral contents in colostrum, milk and blood serum of calves were not influenced to a relevant degree. In conclusion, Primi-C did not, in contrast to Multi-C, develop subclinical hypocalcaemia (<2.0 mmol Ca/l). Prevention of hypocalcaemia with one SGE bolus applied three to four days prior to expected calving was successful in maintaining blood Ca within normal range in Multi over the critical first two days and up to the first three weeks of lactation, without any observed detrimental effects on cows or calves.

Tisagenlecleucel Leukapheresis and Manufacturing Outcomes in Patients Less Than 3 Years of Age with Relapsed/Refractory Acute Lymphoblastic Leukemia

Background: Tisagenlecleucel is an anti-CD19 chimeric antigen receptor (CAR)-T cell therapy approved for patients (pts) ≤25 years of age with B-cell acute lymphoblastic leukemia (B-ALL) that is refractory or in second or later relapse. Pts <3 years of age were excluded from tisagenlecleucel clinical trials in relapsed/refractory (r/r) ALL (NCT02435849 [ELIANA]; NCT02228096 [ENSIGN]). We present leukapheresis and tisagenlecleucel manufacturing outcomes in pts <3 years old with r/r B-ALL in the US commercial setting since regulatory approval.Methods: Qualified pts were <3 years of age at time of request for commercial tisagenlecleucel, with manufacturing data after August 30, 2017 (date of first FDA approval of tisagenlecleucel). Only pts whose tisagenlecleucel was manufactured and administered in the US were included; tisagenlecleucel was manufactured at Morris Plains, NJ, USA. Pt leukapheresis and manufacturing outcome data are presented for all pts and stratified by weight (<10 kg and ≥10 kg) and age (<1 year old and 1-3 years old). These data provide an extended analysis (cut-off March 31, 2021) from the previous report (Eldjerou, 2019).Results: Among 65 pts, the median age was 15.6 months (range, 3.6-36); median body weight was 10.4 kg (range, 6-20) at leukapheresis; 105 leukaphereses were performed in 65 pts (49 <10 kg and 56 ≥10 kg). A median of 1 leukapheresis day was required to meet adequate cell counts (range, 1-4 <10 kg and 1-6 ≥10 kg). The median total blood volume reported in 53/65 pts was 3.5 L (range, 1.3-14.3). The acceptance criteria for tisagenlecleucel manufacture (total nucleated cells: ≥2.0 × 10 9, CD3+ count: ≥1.0 × 10 9, CD3%: ≥3%) were met in 59/66 (26 <10 kg and 33 ≥10 kg) leukapheresis materials; 7/66 did not meet acceptance criteria but proceeded to manufacturing. Following leukapheresis, median percent cell populations were: T cells 55.1% (58% <10 kg and 54.8% ≥10 kg), B-cells 16.9% (20.3% <10 kg and 14.6% ≥10 kg), natural killer cells 4% (3.8% <10 kg and 4.7% ≥10 kg), and monocytes 3.9% (2.6% <10 kg and 4.9% ≥10 kg).Manufacturing success is the formulation of a final product within approved specifications. Out of 66 manufacturing batches (23 batches <1 year old and 43 batches 1-3 years old; 29 batches <10 kg and 37 batches ≥10 kg), 55 (83.3%) were successful. Of the 59 manufacturing batches that met acceptance criteria, 50 were within specification, 2 were terminated, and 7 were out-of-specification due to cell viability (n=4), CAR+% expression (n=2), or another reason (n=1). One pt who experienced manufacturing failure was remanufactured successfully with a second attempt. Of the 7 batches that did not meet the acceptance criteria, 5 were within specifications and 2 were terminated. The median manufactured cell dose was 2.3x10 6 CAR+ viable T cells/kg [range, 0.23-4.6x10 6 (2.5x10 6 <10 kg and 2.1x10 6 ≥10 kg)], median percent cell viability was 90.6% [range, 66.7%-98.3% (91.9% <10 kg and 90% ≥10 kg)], median CAR+ percent expression was 12.0% [range, 2.1%-37.2% (12.2% <10 kg and 11.8% ≥10 kg)]. From 2017 to 2021, the frequency of CD3+ cells present in the leukapheresis material was greatest in 2021 (Figure, left panel). The percentage of in-specification products was 69%-83% in 2017 to 2019 and increased to 89% and 100% in 2020 and 2021, respectively. Additionally, the number of terminations decreased over time (Figure, right panel).Measures for successful leukapheresis in low-weight infant/toddler pts include verification of absolute lymphocyte and/or CD3+ counts on the day prior to the leukapheresis procedure, maintenance of hematocrit levels at 40%, adequate venous access, blood prime of the leukapheresis instrument, prevention of hypocalcemia, and consideration for allowing for >1 day of leukapheresis for the pt to meet the acceptance criteria when medically feasible/safe. During leukapheresis, hypothermia must be prevented, and the pt must be monitored for hypocalcemia, hypomagnesemia, and alkalosis.Conclusions: Leukapheresis and tisagenlecleucel manufacturability in pediatric pts with r/r B-ALL <3 years old and low weight (lowest 6 kg, youngest 3.6 months) continues to be feasible and leukapheresis and manufacturing outcomes show an improvement over time. Communication among cross-functional teams within and between the institution and manufacturer have been key for achieving these advancements. Clinical outcome data for these pts are currently being explored. [Display omitted] DisclosuresWillert: Novartis Pharmaceuticals Corporation: Current Employment. Fong: Novartis Pharmaceuticals Corporation Canada: Current Employment. Clough: Novartis Pharmaceuticals Corporation: Current Employment. Magley: Novartis Pharmaceuticals Corporation: Current Employment. Shojaee: Novartis Pharmaceuticals Corporation: Current Employment. Tiwari: Novartis Healthcare Pvt. Ltd: Current Employment. Acker: Novartis Pharmaceuticals Corporation: Current Employment.

Is preoperative calcium and vitamin D supplementation effective in prevention of postoperative hypocalcaemia in thyroidectomised patients?

IntroductionHypocalcaemia remains the most common postoperative complication after total thyroidectomy. The purpose of the study was to evaluate the clinical usefulness of routine preoperative oral calcium and vitamin D supplementation in the prevention of hypocalcaemia after total thyroidectomy.Material and methodsOne hundred fifty-three consecutive patients with nontoxic multinodular goitre were randomly assigned to routinely receive (group B) or not to receive (group A) calcium carbonate (3 g/d) and alfacalcidol (1 µg/d) on the day before surgery and calcium carbonate (1 g/d) and alfacalcidol (1 µg/d) taken once in the morning on the day of operation. Their preoperative 25-hydroxyvitamin D (25-OHD) levels, hypocalcemic symptoms, serum calcium and parathyroid hormone (iPTH) levels were determined 6 and 24 hour postoperatively and 6 weeks after surgery.ResultsSymptomatic hypocalcaemia was observed in 41/153(26.79%) patients. The incidence of symptomatic hypocalcaemia was significantly lower in the supplemented group than in the group not receiving supplementation: 10 of 77 participants (12.99%) versus 31 of 76 patients (40.79%) (p&lt;0.05). The rates of laboratory and severe hypocalcaemia (corrected calcium &lt;2.0 mmol/l) were 67.11% and 28.95% in group A and 50.65% and 9.09% in group B, respectively (p=0.04, p&lt;0.05). There were no significant differences between groups A and B in corrected calcium levels after surgery and postoperative decreases in corrected calcium levels (p=0.06). 112(73.20%) participants had 25-OHD&lt;20 ng/ml. Vitamin D levels did not influence corrected calcium level changes (p=0.98).ConclusionsOral supplementation of calcium and alfacalcidol may help in the prevention of postthyroidectomy hypocalcaemia. Vitamin D deficiency was widespread among operated patients.

Epidemiological, clinical, pathological aspects, diagnosis, prophylaxis and treatment of hypocalcemia in cattle: Review

Hypocalcemia is a relatively common metabolic disease in dairy cows during the transition period, a time when profound hormonal, anatomical and physiological changes occur in the animal body in order to prepare the female for delivery and later milk production. This can occur in two ways: the subclinical form, when the serum calcium values are below 8.5 mg / dL and the clinical form when the calcium values are below 5.5 mg / dL. The damage caused to dairy cattle is considerable, especially in the subclinical form of occurrence, in which the absence of demonstration of clinical symptoms makes diagnosis difficult. The disease usually occurs around 24 to 48 hours after delivery, where there is a decrease in circulating serum calcium levels, since there is a great demand for colostrum production and delivery. The clinical diagnosis is based on the animal's history and clinical signs, and by measuring the mineral in the blood. Clinical therapy with calcium-based solutions shows good results in the field when the diagnosis is quick and accurate. However, it is noteworthy that prophylaxis is the best option, improved by good nutritional management in the dry and transitional period, by monitoring the ECC, using anionic diets concurrently with the monitoring of urinary pH acidification. In addition, it has been cited as an alternative for the prevention of hypocalcemia, the provision of drench for periparturient cows as one of the prophylaxis alternatives to the disease. This review aims to list the etiology, clinical symptoms, diagnosis, treatment and prophylaxis of hypocalcemia in dairy cattle.

Effect of head covering on phototherapy induced hypocalcemia in term neonates with hyperbilirubinemia: A randomised controlled study.

Phototherapy is the primary treatment for hyperbilirubinemia in neonates. Hypocalcemia is a lesser known but potential detrimental effect of phototherapy. It has been hypothesized that phototherapy inhibits pineal secretion of melatonin, which blocks the effect of cortisol on bone calcium. Therefore, unchecked cortisol increases bone uptake of calcium and induces hypocalcemia. Covering head during phototherapy in order to prevent light reaching to the pineal gland which eventually leads to the prevention of hypocalcemia is hypothesized to prevent hypocalcemia but it lacks sufficient evidence worldwide. It is a prospective, randomized controlled study. 112 neonates were randomized into two groups of 56 neonates. Group A underwent phototherapy without head cover and group B with head covered by a cap. The mean decline in serum ionic calcium after 48 hours of phototherapy in group A and group B was 0.57±0.37 mg/dl and 0.34±0.24 mg/dl respectively. This decline in serum ionic calcium was significantly higher in group A. (p < 0.001). 26.8% newborns from group A developed hypocalcemia while in group B only 14.3% developed hypocalcemia however it was not found to be statistically significant. Incidence of symptomatic hypocalcemia between the two groups was also not significant. There was significant reduction in serum calcium in neonates undergoing phototherapy without head cover as compared to neonates with head cover but risk of hypocalcemia was not significant. Further studies with larger sample size including preterm are recommended.

Etiology, therapy and prophylaxis of bovine parturient paresis (hypocalcaemia)

Due to the sudden increase of calcium demand at the onset of lactation many high yielding dairy cows experience a certain level of hypocalcaemia following parturition. The incidence of hypocalcaemia (parturient paresis) increases with age but also depends on many other factors such as the acid-base status and the availability of calcium as well as other minerals and trace elements. Hypocalcaemia can easily be treated by supplementation of calcium parenterally or orally, nonetheless, prophylaxis of the condition should be the main focus in modern dairy farming, in order to avoid its negative effects. Oral administration of calcium around parturition is the simplest way of prophylaxis, but results in a high work load and requires exact knowledge of the date of parturition. The latter also applies for the parenteral administration of vitamin D3, which should be injected 1 week before parturition. Additionally, repeated treatment with vitamin D increases the risk for calcinosis. Reducing the calcium concentration of the ration fed during the late dry period also decreases the risk for hypocalcaemia by activating the mechanisms for calcium homeostasis within the body. The induction of a mild (compensated) metabolic acidosis to increase the sensitivity of parathormone receptors and enhance intestinal calcium uptake may also be employed to prevent milk fever. For this purpose, a DCAD (dietary cation anion difference) diet is fed during the late dry period, in which the concentrations of strong cations (potassium and sodium) as well as strong anions (sulfate and chloride) are altered. This may either be achieved by reducing the potassium concentration (partial-DCAD) or by adding anionic salts (full-DCAD). This method, especially the full-DCAD variant, requires a substantial level of surveillance and monitoring. Suitable prophylactic measures for the prevention of hypocalcaemia must be chosen individually for each farm, depending on the incidence of hypocalcaemia as well as personnel and structural resources.

Calcium and Vitamin D supplementation in the prevention of post-operative hypocalcaemia in thyroidectomy

Introduction: The incidence of transient hypocalcaemia after thyroidectomy varies in centres. It increases morbidity and delays discharge. This randomised controlled trial aimed to ascertain the usefulness of calcium and Vitamin D supplementation for 1 week pre-operatively in the prevention of hypocalcaemia in patients undergoing total thyroidectomy (TT) for multi-nodular goitre. Methodology: Patients undergoing TT for multi-nodular goitre from January 2019 to August 2019 were included in the study. They were randomly divided into two groups by block randomisation. Group A received oral calcium (500 mg every 6 h) and Vitamin D (calcitriol 0.25 mg every 6 h) 7 days before surgery and Group B did not receive supplementation. Symptoms and signs of hypocalcaemia were monitored. Calcium profile was measured pre-operatively and post-operatively at 6 h, 24 h, 72 h and 14th day. Serum calcium level ≤8.5 mg/dl was considered as hypocalcaemia. Results: 8/62 patients in Group A and 26/62 in Group B had symptoms of hypocalcaemia. 11/62 patients in Group A and 34/62 in Group B developed signs of hypocalcaemia. 15/62 patients in Group A and 36/62 in Group B had biochemical hypocalcaemia. 9/62 patients in Group A and 25/62 in Group B developed post-operative hypocalcaemia, which required post-operative oral supplementation. 3/62 patients in Group A and 16/62 in Group B needed post-operative intravenous calcium supplementation. Conclusions: It is concluded that post-operative hypocalcaemia which manifested as signs and symptoms and correlated with biochemical values was lower after receiving pre-operative oral calcium and Vitamin D3 supplement for 7 days. The need for post-operative supplementation was lower in this group.

Role of perioperative calcium and vitamin D supplementation in prevention of hypocalcemia after total thyroidectomy

Background: Thyroid surgery is one of the most frequently performed surgical procedures worldwide. Total thyroidectomy is a recommended procedure for most of the thyroid diseases. The most common complication resulting after this surgery is transient hypocalcemia - the incidence is 24% - which increases the morbidity rate and increases the length of stay in the hospital. Objective: The aim of the present randomized controlled trial was to ascertain the usefulness of pre- and post-operative calcium and Vitamin D supplementation in prevention of hypocalcemia after total thyroidectomy. Materials and Methods: It was a prospective randomized controlled study conducted at Department of Surgery, Derna Teaching Hospital, Libya from February 2018 to august 2019. A total of 100 patients of both genders undergoing total thyroidectomy were included in the study, Patients undergoing reoperation for thyroid disease, American Society of Anesthesiologists (ASA) grade 3 or above, patients with chronic renal failure were excluded. The patients were sorted into two groups by lottery method; Group 1 received oral calcium (500 mg every 6 h) and Vitamin D (calcitriol 0.25 mcg every 6 h) 3 days before and 7 days after the surgery; and Group 2 did not receive supplementation. Total thyroidectomy was done and Calcium profile was measured pre- and post-operatively at 6, 12, 24, 48, 72 h, and on 30th day. Hypocalcemia after surgery was either symptomatic or laboratory documented. Serum calcium level ≤ 8.5 mg/dl was considered as laboratory hypocalcemia. The final outcome was measured at one month. Data was analyzed via the Statistical Package for Social Sciences version 22.0 (IBM Corp, Armonk, NY, USA). P value ≤ 0.05 was considered significant.Results: More patients from Group 2 than patients from Group 1 developed symptomatic hypocalcemia (P < 0.01) clearly at 48h and 72h times. Laboratory hypocalcemia within postoperative 24 h was comparable between two groups, but more patients of Group 2 compared to Group 1 developed hypocalcemia at 48 h (10 and 21 respectively; P = 0.04) and at 72 h after surgery (13 and 23 respectively; P = 0.01). Preoperative serum calcium was only independent variable significantly associated with development of 24 h post-operative hypocalcemia.Conclusion: Routine pre- and post-TT calcium and Vitamin D supplementation can significantly reduce postoperative hypocalcemia. Which ultimately can also decrease prolonged hospitalization of patients and costs associated with multiple blood sampling.

Activated vitamin D3 formulations can be safely used as concomitant medication for prevention of denosumab-induced hypocalcemia in women with postmenopausal osteoporosis.

Denosumab prevents osteoporosis by potently inhibiting bone resorption, but requires oral therapy with calcium and vitamin D preparations to prevent the side effects of hypocalcemia. Generally, a combination drug containing calcium, natural vitamin D, and magnesium is used. However, if activated vitamin D has been used before the initiation of denosumab therapy, continued use of activated vitamin D is not uncommon. This study aimed to evaluate the combination vitamin D preparation, alfacalcidol, and eldecalcitol on the therapeutic effect on denosumab therapy, the preventive effect on hypocalcemia, and the effect on renal function, to determine the optimal choice of concomitant medication. This is a retrospective and single-center study. Among 39 patients who had used denosumab (60 mg dose) for at least 12 months between November 2013 and October 2015, those who used the combination medication concomitantly as the standard treatment, those who used alfacalcidol concomitantly, and those who used eldecalcitol concomitantly were compared. Denosumab therapy markedly increased lumbar spine and femoral neck bone densities at 12 months in the three groups, showing no particular difference in the rate of increase of bone density. The three groups had marked decreases in bone metabolism markers, but had no intergroup differences. No hypocalcemia, hypercalcemia, or obvious renal dysfunction occurred over 12 months. This study indicates that the use of activated vitamin D preparations, as concomitant medications with denosumab therapy, is appropriate considering the therapeutic efficacy of denosumab, prevention of hypocalcemia, and influence on renal function.

Serotonin induces parathyroid hormone-related protein in goat mammary gland.

During lactation, large amounts of calcium are exported from the mammary gland into milk to ensure skeletal growth of the offspring. Recent studies revealed that serotonin (5-HT) is essential to stimulate skeletal calcium resorption for milk synthesis. Our objective was to explore the correlation between circulating 5-HT and serum calcium and parathyroid hormone-related protein (PTHrP) concentrations around parturition in dairy goats. We also investigated the effect of 5-HT on PTHrP expression in cultured primary goat mammary epithelial cells (GMEC). Blood samples of multiparous Guanzhong dairy goats were collected on day -5 to 3 postpartum for analysis of serum concentrations of calcium, 5-HT, and PTHrP. Results revealed that from day -3 to 0 postpartum serum calcium and 5-HT concentrations decreased progressively, but serum PTHrP concentration only had a sharp drop in the postpartum period sampled. Correlation analysis of circulating 5-HT and serum calcium and PTHrP concentrations on day 1 and 2 postpartum revealed that low serum 5-HT concentration was positively correlated with serum total calcium or PTHrP concentration. By knocking down tryptophan hydroxylase-1 (TPH1) or adding 5-hydroxytryptophan (5-HTP) to decrease or increase the levels of 5-HT in GMEC, we observed that 5-HTP increased PTHrP expression in a dose-dependent manner and siTPH1 decreased PTHrP protein expression. Furthermore, 5-HT increased mRNA abundance of calcium-sensing receptor (CaSR) in a dose-dependent manner and decreased the expression of plasma membrane Ca2+ ATPase-1 (PMCA1). Taken together, 5-HT seems to induce PTHrP expression in goat mammary cells during and after parturition. These findings suggest that increasing 5-HT biosynthesis could be a potential therapeutic target for prevention of hypocalcemia in dairy goats.

Short Term Effects of Dietary Boron on Mineral Status in Dairy Cows*

Aim of this study was to obtain knowledge on boron supplemented diet to mineral status of body fluids and feces in short term nutrition of dairy cattle. A total of 24 healthy Holstein dairy cows were used. The animals were fed with standard ration, and boron at three different doses was added to experimental' diets as boron compound: borax, for 10 days. Boron and other macro and trace minerals were determined in serum, milk, urine and feces samples taken on 0 and 11st days. In this study, there were no overt signs of toxicosis, and a pivotal knowledge was obtained in dairy cattle fed with boron supplemented diet on boron absorption, excretion, and its interaction with other minerals. Boron could not completely absorb from gastrointestinal tract. Urine was the most important excretion way of boron. More less boron was also eliminated by milk. Boron levels in body fluids (serum and milk, p less then 0.000) were increasingly changed based on the dose. Boron, among minerals, provided a striking increase for Ca (p less then 0.003) and Mg (p less then 0.028) levels in serum by increasing absorption of these minerals. This topic is worth evaluating as an alternative approach in the prevention of hypocalcemia in transition cows.

Usefulness of pre- and post-operative calcium and Vitamin D supplementation in prevention of hypocalcemia after total thyroidectomy: A randomized controlled trial.

Background:Total thyroidectomy (TT) is a commonly performed surgery and postoperative hypocalcemia is a major detriment to early discharge. The aim of this randomized controlled trial was to ascertain the usefulness of routine pre- and post-operative calcium and Vitamin D supplementation in prevention of hypocalcemia after TT.Materials and Methods:Sixty consecutive patients who underwent total or near TT from February 2013 to August 2014 were included in the study. They were randomly divided into two groups - Group 1 received oral calcium (500 mg every 6 h) and Vitamin D (calcitriol 0.25 mcg every 6 h) 7 days before and 7 days after the surgery; and Group 2 did not receive supplementation. Symptoms and signs of hypocalcemia were monitored. Calcium profile was measured pre- and post-operatively at 6, 12, 24, 48, 72 h, and on 30th day. Hypocalcemia after surgery was either symptomatic or laboratory documented. Serum calcium level ≤ 8.5 mg/dl was considered as laboratory hypocalcemia.Results:Twelve patients from Group 2, and 3 patients from Group 1 developed symptomatic hypocalcemia (P < 0.01). Laboratory hypocalcemia within postoperative 24 h was comparable between two groups, but more patients of Group 2 compared to Group 1 developed hypocalcemia at 48 h (6 and 13, respectively; P = 0.04) and at 72 h after surgery (5 and 14, respectively; P = 0.01). Twenty-four hours postoperative serum calcium level was significantly associated with grade of goiter, preoperative calcium, and nature of thyroid disease (benign or malignant). On multiple linear regression analysis, preoperative serum calcium was only independent variable significantly associated with development of 24 h post-TT hypocalcemia.Conclusion:Routine pre- and post-TT calcium and Vitamin D supplementation can significantly reduce postoperative hypocalcemia.

Elevation of circulating serotonin improves calcium dynamics in the peripartum dairy cow.

Hypocalcemia is a metabolic disorder that affects dairy cows during the transition from pregnancy to lactation. Twelve multiparous Holstein cows and twelve multiparous Jersey cows were intravenously infused daily for approximately 7 days prepartum with either saline or 1.0mg/kg bodyweight of the immediate precursor to serotonin synthesis, 5hydroxy-l-tryptophan (5-HTP). On infusion days, blood was collected before, after, and at 2, 4, and 8h postinfusion. Blood and urine were collected daily before the infusion period, for 14 days postpartum and on day 30 postpartum. Milk was collected daily during the postpartum period. Feed intake and milk yield were unaffected by 5-HTP infusion postpartum. Cows infused with 5-HTP had elevated circulating serotonin concentrations prepartum. Infusion with 5-HTP induced a transient hypocalcemia in Jersey cows prepartum, but not in any other treatment. Holstein cows infused with saline had the highest milk calcium on the day of and day after parturition. Postpartum, circulating total calcium tended to be elevated, and urine deoxypyridinoline (DPD) concentrations were elevated in Holstein cows infused with 5-HTP. Overall, Jerseys had higher urine DPD concentrations postpartum when compared with Holsteins. Taken together, these data warrant further investigation of the potential therapeutic benefit of 5-HTP administration prepartum for prevention of hypocalcemia. Further research should focus on delineation of mechanisms associated with 5-HTP infusion that control calcium homeostasis during the peripartum period in Holstein and Jersey cows.

Is calcitonin an active hormone in the onset and prevention of hypocalcemia in dairy cattle?

The objective of this study was to assess the potential importance of calcitonin (CALC) in the onset of subclinical hypocalcemia (experiment 1) and in the physiological mechanisms underlying the prevention of bovine hypocalcemia under metabolic acidosis (experiments 2 and 3). In experiment 1, 15 Holstein cows naturally incurring subclinical hypocalcemia during the first 5d postpartum were classified as low subclinical hypocalcemia (LSH) when blood Ca concentrations were between 7.5 and 8.5mg/dL, or as high subclinical hypocalcemia (HSH) when blood Ca concentrations were between 6.0 and 7.6mg/dL. Blood samples were taken daily from d −5 to 5 relative to parturition to determine concentrations of parathyroid hormone (PTH), CALC, and 1,25(OH)2D3. In experiment 2, 24 Holstein bulls (497±69kg of body weight and 342±10.5d of age) were assigned to 2 treatments (metabolic acidosis or control). Metabolic acidosis was induced by an oral administration of ammonium chloride (2.5mEq/d) during 10 d, and animals were slaughtered thereafter. Blood samples were collected before slaughter to determine CALC, PTH, 1,25(OH)2D3, and samples of urine, kidney, parathyroid, and thyroid glands were obtained immediately after slaughter to determine expression of several genes in these tissues. Last, in experiment 3, we tested the activity of CALC under metabolic acidosis in vitro using breast cancer cell (T47D) cultures. Although PTH tended to be greater in HSH than in LSH, the levels of 1,25(OH)2D3 were lower in HSH cows (experiment 1). Blood CALC concentration was not affected by the severity of subclinical hypocalcemia, but it was influenced by days from calving (experiment 1). The expression of PTH receptor (PTHR) in the kidney was increased under metabolic acidosis (experiment 2). Furthermore, the activity of CALC was impaired under acidic blood pH (experiment 3). In conclusion, the CALC rise in HSH cows after calving impaired the recovery of blood Ca concentrations because the PTHR response was not sufficient to activate 1,25(OH)2D3 and compensate for the CALC effect. Metabolic acidosis prevents hypocalcemia because the expression of PTHR is upregulated in the kidney, resulting in an increased PTH activity and a subsequent increase in 1,25(OH)2D3 serum concentrations. Moreover, an impairment of CALC activity at low pH enhances the hypercalcemic role of PTH.

Nutritional considerations to maximise fertility performance in dairy farms — metabolic disease

This is the third article in a series outlining the pertinent nutritional considerations for maximising fertility performance in dairy cows. This article will cover details of: the interactions between the physiological pathways for metabolic and reproductive control/signalling; detrimental impacts on fertility performance of excessive negative energy balance (NEB) and subsequent lipid metabolism; the impact and mechanisms of hypocalcaemia on reproductive performance; and guidelines for monitoring metabolic parameters and intervention levels. The author would refer readers to the first article in this series ( Gammon, 2015 ) for practical advice on rationing and nutritional recommendations to manage body condition score, ensure provision of adequate macro (energy (fat and starch)) components of diets to avoid excessive NEB, lipid metabolism and to Gammon (2014) for more detail on the prevention of hypocalcaemia.

Milk fever prevention: a clinical review of current prevention strategies

Prevention of periparturient hypocalcaemia has been an active area of research and development within the dairy sector for over 60 years. Absolute dietary restriction of calcium to the pre-partum animal is the traditional method but can be challenging in typical UK dairy cow diets. Supplementation of calcium binding compounds will effectively lower the dietary calcium by decreasing absorption across the gut wall, allowing calcium restriction on a ‘normal’ diet. Manipulation of the dietary acid/base balance of the pre-partum animal is another effective tool for prevention of hypocalcaemia. Reduction of dietary cations (sodium and potassium) relative to the anions (chloride and sulphur) induces a mild to moderate metabolic acidosis which stimulates the parathyroid hormone homeostatic mechanisms, up-regulating bone resorption and gut absorption while reducing renal excretion of calcium. The physiology of normal calcium regulation and how these hypocalcaemia prevention strategies exploit this understanding will be discussed in this article along with other important considerations.

The role of intraoperative calcium injection for prevention of postoperative hypocalcaemia after total thyroidectomy

ObjectiveThe aim of this study was to evaluate the possible role of intraoperative intravenous calcium injection in avoidance of unexplained postoperative hypocalcaemia.BackgroundThyroid surgery has always been the most common endocrine surgical operation. Total thyroidectomy is generally reserved for patients with thyroid malignancy, toxic thyroid, clinically significant goiter and less commonly for thyroiditis. The complications include recurrent laryngeal nerve injury, external branch of superior laryngeal nerve injury, neck hematoma, and hypocalcaemia. Post-thyroidectomy hypocalcaemia can occur in about 9.5-15.4% of the patients. The prevention of hypocalcaemia is the main concern, as some patients may experience hypocalcaemia despite preservation of the parathyroid glands during surgery.Patients and methodsThis prospective study on 40 consecutive patients was conducted from March 2011 to January 2013. The patients were randomly divided into two groups: group I (20 patients) received intraoperative intravenous 10 ml of calcium gluconate containing 500 mg of calcium and group II (20 patients) received no injection. Serum calcium level was measured for all patients preoperatively, 6 h and 5 days postoperatively.ResultsThe incidence of postoperative hypocalcaemia was lower in group I than in group II (40 and 65%, respectively); in addition, 35% of the patients in group I suffered from perioral numbness, tingling, and positive Chvostek's sign compared with 50% in group II. In all, 5% of the patients in group I suffered from tetany compared with 15% in group II. Serum calcium levels on the first postoperative day in group I patients were significantly higher than those in group II patients, with mean range of 8.1 ± 0.3 in group I and mean range of 7.8 ± 0.4 in group II.ConclusionThe prophylactic intravenous injection of calcium gluconate during total thyroidectomy is effective in minimizing risk for postoperative symptomatic hypocalcaemia.

The effect of MgSO4 addition and the increasing doses of calcium and phosphorus during ending drying period on the occurrence of hypocalcaemia and hypophosphataemia in dairy cows

The aim of the presented study was the estimation of optimal Ca and P levels applied before calving together with anionic salt addition, as an element of hypocalcaemia and hypophosphataemia prevention. The experiment was carried out during the dry period on 48 cows with similar milk yield in the previous lactation. Cows were divided into four groups. In group I (control) the amount of minerals was in accordance to NRC standards. In experimental groups (groups II-IV), two weeks before calving, cows received 140 g/day/head of hydrated magnesium sulphate to achieve dietary cation-anion difference at the level of about 50 mEq/kg DM. In groups II and III cows received calcium carbonate (100 g/day) 10 days a.p. (antepartum) (group II), or 5 days a.p. (group III), while cows in IV group received dicalcium phosphate (100 g/day) for 5 days a.p. Application of MgSO4 x 7H20 significantly affected the urine pH of cows from group III and IV 4-5 d. before calving - 6.45 and 6.81, respectively. The acidification of urine was observed after calving in group IV (7.13). In cows from group II (100 CaCO3 10 days a.p.) urine pH decline was not found (7.97-7.75). In that group the incidences of hypophosphatemia were noted (blood serum inorganic P level 1.41-1.46 mmol/1). Addition of magnesium sulphate prevented hypocalcaemia occurrence -- 4-5 d. before calving the concentration of ionized Ca in blood serum was 1.11, 1.13 and 1.16 mmol/1 (respectively for group II, III and IV). Reproductive functions were significantly improved after the application of CaCO3 and CaHPO4 for 5 days a.p. in comparison with control and group II -- progesterone concentration in the blood serum on the 45th day of lactation was 1.396 - 1.409 versus 0.799 - 0.401. The correlation between progesterone and inorganic P level in serum was almost significant. Based on the obtained results a treatment optimal in prevention of hypocalcaemia and hypophosphataemia is the application of 50 g CaCO3 and 50 g of CaHPO4 for the last 5 days of the dry period together with MgSO4 x 7H20 given for 14 days a.p.

Prevention of postoperative hypocalcemia with routine oral calcium and vitamin D supplements in patients with differentiated papillary thyroid carcinoma undergoing total thyroidectomy plus central neck dissection

Routine oral calcium and vitamin D supplementation may prevent hypocalcemic crisis, but its efficacy has not been studied in patients undergoing thyroidectomy plus central neck dissection (CND). The authors therefore prospectively evaluated the clinical usefulness of routine oral calcium and vitamin D supplementation for prevention of hypocalcemia after total thyroidectomy and CND. Of 197 patients with differentiated papillary thyroid carcinoma, 49 underwent total thyroidectomy alone, and 148 underwent total thyroidectomy plus CND. The latter were randomized to oral calcium (3 g/day) plus vitamin D (1 mg/day) (Group A, n=49), calcium alone (Group B, n=49), or no supplements (Group C, n=50). Hypocalcemic symptoms, serum calcium, and parathyroid hormone (PTH) levels were compared among the groups. Group C had significantly higher incidences of symptomatic (26.0% vs 6.1%; P<.015) and laboratory (44.0% vs 14.3%; P<.015) hypocalcemia than the group without CND. The incidences of symptomatic and laboratory hypocalcemia were significantly decreased in Groups A (2.0% and 8.2%, respectively) and B (12.2% and 24.5%, respectively) (P<.05). Serum calcium levels decreased in most patients after surgery, but recovered earliest in Group A. Hypercalcemia and PTH inhibition did not occur in gs A and B. Compared with total thyroidectomy alone, CND significantly increases the rate of postoperative hypocalcemia, which can be prevented by routine postoperative supplementation with oral calcium and vitamin D.