Dr JANVI SARMA

MBBS MD

DRUGS: CALCIUM CHLORIDE,CA LCIUMGLUCONATE,MGSO4,KCL,NAHCO3

CALCIUM

• RDA (elemental)

1. 1-1.2 g (adults)

2. 200mg (1-6mons)

3. 260mg(6-12mons)

4. 700mg(1-3yrs)

5. 1000mg(4-8yrs)

6. 1300mg(9-18yrs)

• 2 forms

1. Ca chloride

2. Ca gluconate

• Both available as 10% w/v

• Elemental Ca in Cacl2 = 1g=273mg =13.6MEq= 6.8mmol

• Elemental Ca in Ca gluconate=1g= 93 mg=4.65MEq

• Indications :-

1. Hypocalcemic tetany

2. Hypocalcemia d/t hypopatathyroidism

Dose:Cacl2- acute symptoms- 200-1000mg or 2.7-5mg/kg

every 4-6hrs.Ca gluconate- 1-2 g over 2hrs.or

Severe symp- 1g over 10mins,repeat every 10mins until symptoms resolve

Ca gluconate- 1-2 g over 10mins,repeat every 60mins until symp resolve.infusion- 5-20mg/kg/hr

Note: i.v ca gluconate preferred over ca chloride d/t potential of extravasation with cacl2.

3. BB overdose-

Dose:-Cacl2- 20mg/kg over 5-10mins f/b 20mg/kg/hr titrated

to adequate hemodynamic response

4. CCB overdose-

Dose- Cacl2- 1-2g over 5mins,may repeat every 10-20minsCa gluconate- 60mg/kg/dose(max-3-6g/dose)over

5mins.may repeat 3-4 additional doses.

5. Cardiac toxicity d/t- ↓ca/-Cacl2- 500-1000mg over 2-5mins.repeat as

necessary/20mg/kg(max 2g)Ca gluconate- 1.5-3g over 2-5 mins.peds-

60-100mg/kg/dose( max-3g/dose).

6. In hyperkalemia as membrane stabiliser

ADR

• CVS- brady/arrest/arrythmias/hypotension/syncope

• CNS- tingling sensation

• Endo/metabolic- hot flush

• GIT- chalky taste,GI irritation

• Local- tissue necrosis

• Renal- nephrolithiasis

INTERACTIONS

• Increased risk of cardiac arrythmias when used with cardiac glycosides.

• Concurrent use with NMBA reverse their effect

• Acidosis- use with caution in pts with resp acidosis,renal imapirment- acidifyoing effect of Cacl2.

• ↑phosphatemia- use with caution as elevated levels of pos & Ca may result in softvtissue & pul art Ca-Po4 precipitation.

CONT…..• Hypokalemia- use with caution in pts with severe hypoK

as acute rise in Ca can result in life threatening arrythmias.

• Ceftriaxone- Concurrent use may cause precipitation.

• Dobutamine- Ca salts may diminish the therapeutic effect of dobutamine.

• Thiazide- It may decrease excretion of Ca salts & may cause met alkalosis.

• Hypo Mg- It is common cause of hypo Ca.

MAGNESIUM SULPHATE

• 4th m/c cation in the body

• 60% present in bones

• Imp roles in – N-M function & CV tone

• RDA: (Mg)

1. 310-400mg (adult)

2. 80mg (1-3yrs)

3. 130mg(4-8yrs)

4. 240mg(9-13yrs)

5. 350mg( Preg)

• MgSo4- available as 50% w/v

• 1ml = 500mg = 4MEq

• 1 Meq = 123mg of MgSO4

• 1 mmol = 2MEq = 24mg of elemental Mg

• PD’s & Pk’sOnset – i.m – 1hr , i.v – immediateDOA- im- 3-4hrs , i.v- 30minsProtein binding – 30% to albuminExcreted in urine

INDICATIONS

1. Severe pre eclampsia & eclampsia

2. Hypomagnesemia – Mild- 1 g every 6hrsMild-mod- 1-4g. /> 12g in 12hrsSevere-4-8g at <1g/hrSevere symp- <4g over 4-5mins

3. Correction of hypokalemia

4. TDP- 1-2 g over 1-2 mins

5. Acute severe exacerbation- 2g as a single dose over 20mins.Peds- 25-75mg/kg/dose.max 2g

6. Part of TPN- 8-24MEq of elemental Mg daily

7. To attenuate intubation response

In impairments:

1. Hepatic- no adjustment

2. Renal- dec by 50%. In eclampsia not >20g/48hrs

Compatibility- DNS/D5/LR/NS.incompatible with fat emulsion.

ADR:

1. CVS- flushing,hypotension

2. Endo- hyper Mg

• CI

1. Heart block

2. Myocardial damage

• Precautions/cautions

1. In pts with N-M ds

2. Renal impairment

3. Check DTR every 15mins.Disappearance of patellar reflex is useful clinical sign to detect onset of Mg intoxication.Knee jerk should be tested before repeating dose

4. Periodic monitoring of S.Mg is essential.Keep S.Mg <2.5MEq/L.If >3.5 discontinue infusion.

5. UO = 100ml/4hrs

INTERACTIONS

• Biphosphonate derrivatives- Mg salts may dec the S.conc of biphos.Avoid administration of oral Mg salts within 2hrs before/after. Exception- Pamidronate

• CCB- It may enhance the toxic effects of Mg salts

• CNS depressants- MgSO4 may enhance the effects of these drugs

• Levothyroxine- Mg salts may dec the S.conc of levothyroxine.Gap of atleast 4hrs req.

NAHCO3

• Hypertonic solution

• Conc- 4.2%, 5%,7.5% (22.5Meq /ampoule), 8.4% w/v

• w/v- mass of solute/vol of sol * 100

• Contents: 1 Meq = 84mg , 1g= 12MEq of Na & Hco3

• 84mg/ml NaHCO3 ( 1:1 Na : Hco3 /ml)

• MOA- increases plasma HCO3, buffers excess of H ions & increases blood ph

• Uses:

1. Met acidosis- when ph <7.1 guidelines for using NAHCO3 in met acidosisWhy to treat?

• Met acidosis supress cardiac contractility

• Persistent acidosis will consume the bone buffers & cause osteoporosis.

How much ?

• Amount of NAHCO3 req= 0.5*wt* (desired- actual)

OR

• Dose( Meq) = 0.3* Wt* BE

How to infuse

• In absence of CI,50% of calculated deficit is corrected in 4hrs & rest gradually over 24hrs

• To avoid irritation of veins,its added to D5.

SPECIAL PRECAUTIONS

• NAHCO3 should not be used as bolus

• Never treat acidosis without treating the etiology

• Never correct acidosis without correcting associated hypoK.because by correcting acidosis,NAHCO3 will shift K intracellularly

• Do not mix with Ca- precipitation

USES CONTD…..

2. Salicylate poisoning.

3. TCA overdose

4. Methanol poisoning

5.Hyper K- 50MEq over 5 mins (ACLS 2010)

6. Urine alkalinization- 48MEq, then 12-24 Meq every 4 hrs.Doses adjusted to desired urinary pH.

7. CIN- (off label use) – 154 Meq/L in D5 @ 3ml/kg/hr * 1hr before contrast,then 1ml/kg/hrhr during contrast & for 6 hrs after procedure.

8. Cardiac arrest- 1 Meq/kg/dose

** Routine use not recommended ( in some situations like arrest d/t met acidosis/hyper K/ TCA overdose.

• ADR:

1. CVS- CHF,edema

2. Cerebral H

3. CNS- tetany

4. GIT- gastric distension/flatulence

5. Endo/metabolic- hyper Na/hyper osm/hypo kalemia/hypo Ca

6. Resp- pul edema

INTERACTIONS

1. Acetazolamide- May increase the toxic effects of NAHCO3

2. Alpha & Beta agonist- Alkalinizing agents may increase the S.conc

3. Cefodoxime/Cefuroxime- Antacids may dec S.conc

KCL

RDA

• 40-80 Meq/day

• 2-3 Meq/kg/day (children)

• 2-6 Meq/kg/day ( Infants)

Total body K- 3500 Meq ,(98% is IC & 2% EC)

Uses:

• Conduction of nerve impulses in brain,heart,sk muscle

• Contraction of muscles

Composition

• Inj Kcl- 15% = 10ml

• 1ml= 150mg=2Meq

• 10ml=1.5g=20MeqIndications

1. Hypokalemia

2. Added to K free peritoneal dialysis fluid to maintain proper K level

3. During CPB Sx

Basic rules

• Max dose- 20 Meq/hr thr peripheral line & 40 Meq/hr thr central line

• Ideally ≠20/hr, ≠40/L, ≠240/day

• Av rise of K is 0.25Meq/L when 20Meq is given during 1hr

• 1Meq fall in S,pot = 200-400Meq of total body pot deficit.

S.K >3.5 3 2 <2

TOTAL K DEFICIT

0 300 450-600 >600

• ADR:

Skin- rash

Endo – hyper K

GIT- abd pain/diarrhoea/GI bleed/ GI perforation(oral)/N+V.

• Warnings

1. Acid base dis

2. CVS ds- pts are prone to cardiac effects with hypo/hyper K

3. Renal impairment- use with caution

4. Pts on digitalis

• Drug interactions:

1. ACEI/AR2 B

2. Anticholinergics – may enhance ulcerogenic effect of Kcl

3. Heparin – May increase hyperkalemic effect of Kcl.

THANK YOU