Iso-tex Diagnostics, Inc.

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Iso-tex Diagnostics, Inc. Drugs

Glofil-125

Glofil-125

The suggested dose range employed in the average patient (70 kg) is as follows:

Continuous intravenous infusion: 20 to 100 μCi (0.74-3.7 megabecquerels)

(Sigman, et al (1) method).

Single intravenous injection: 10 to 30 µCi (0.37-1.11 megabecquerels)

(Cohen, et al (2) method).

The patient dose should be measured by a suitable radioactivity calibration system

immediately prior to administration.

Technique Continuous intravenous infusion

Sigman1 method

I. Preparation:

1. Adequate diuresis (a urine flow exceeding 3 mL/min.) is established, preferably

by an oral water load of 1,500 mL two hours prior to the beginning of the

clearance study.

2. It is not necessary to withhold breakfast or admit the patient the night before.

II. Procedure:

1. After the establishment of adequate diuresis, a number 14 or 16 French Foley

catheter is aseptically inserted into the bladder.

2. An intravenous infusion of Lactated Ringers (Hartmanns) solution is started

in each arm, one to maintain a site for injection of the GLOFIL-125, the other

to serve as a site for serial withdrawal of blood. A two-way stopcock connects

the needle and intravenous tubing of each arm.

3. The dose is equally divided into (1) an intravenous priming dose to be injected

as is and (2) a sustaining dose to be diluted in 30 to 60 mL of isotonic sodium

chloride, depending on how many collection periods are anticipated.

4. The priming dose is slowly injected into one arm. This is immediately followed

by infusion of the sustaining solution through the same site, usually at the rate of

0.5 mL/min., by means of an automatic pump. During this infusion, the Lactated

Ringers solution in the same arm is discontinued, and 40 to 45 minutes are

allowed for equilibration in order to reach a state of constant plasma

concentration of radioactivity.

5. After attaining equilibrium, consecutive 15 minute collection periods

are started. From the arm opposite the injection site, 5 mL of blood (allowing

duplicate plasma counting volumes) is drawn six minutes prior to the

midpoint of each collection period, placed in heparinized tubes, mixed, and

centrifuged. The blood samples may be obtained through the two-way

stopcock after discarding the first 30 mL aspirated into the syringe. This

30 mL contains the contents of the tubing, including infusion fluid, and must

be cleared in order to obtain an undiluted blood sample. If desired, this step

may be eliminated and blood samples obtained by direct venipuncture.

6. During each collection period, total urine must be accurately collected and

the volume accurately measured. Three such consecutive collection periods

are sufficient for most clinical studies.

III. Clearance Calculations:

1. Aliquots (1 mL each) of plasma and urine from each collection period are

counted in a standard gamma-ray scintillation well detector.

2. All counts are corrected for background activity.

3. Glomerular filtration rate is calculated by the formula C=UV/P, in which:

C = glomerular filtration rate in mL/min U= urinary concentration of radioactivity in net counts/min/mL V= urinary flow rate in mL/min P = plasma concentration of radioactivity in net counts/min/mL

4. Average glomerular filtration rate (GFR) is calculated from the rates for the

individual collection periods. GFR can be expressed in terms of body

weight (mL/min/kg) or body surface area (mL/min/m2).

5. Unilateral glomerular filtration rates can be determined by the same technique

by utilizing ureteral catheterization.

Single intravenous injection

Cohen2 method:

The method of Cohen, et al2 requires little preparation, few and small blood samples,

no bladder catheterization, and no constant intravenous infusion. It is simple to

perform, rapid, and utilizes equipment which is readily available in most modern

laboratories.

I. Preparation:

1. Lugol's solution, 3 drops orally, three times a day, is administered for one or

two days prior to the test.

No diet or water restriction is necessary.

2. Oral water load is begun one hour before starting the test. Start with 20 mL/kg

and force any clear liquids (unless contraindicated) until the test is complete.

II. Procedure: Record actual times for the collection of the blood and urine samples.

1. Empty the bladder and label the urine Urine control.

2. Inject 10-30 µCi GLOFIL-125 intravenously; wait 30 to 60 minutes.

3. Collect the entire urine and label Urine discard.

4. Draw 4 to 5 mL of blood into a heparinized syringe. Label Plasma #1.

5. After another 30 to 60 minutes, collect the entire urine and label Urine #1.

6. Immediately draw another blood specimen. Label Plasma #2.

7. After final 30 to 60 minute wait, collect the urine. Label Urine #2.

8. Draw the last blood specimen immediately. Label Plasma #3.

III. Clearance Calculations:

1. Radioactivity of one mL aliquots of both urine and plasma are determined

using a well-scintillation detector with a single channel pulse-height analyzer.

Sufficiently reproducible counts are usually obtained with time settings of 2

minutes for urine samples and 20 minutes for the plasma samples. Calculations

of the clearance rates are made by using the formula:(1)

C = C = UV/P + 1.73/SA where

C = glomerular filtration rate in mL/min/1.73 m2

U = urine radioactivity in counts/min/mL

V = urine flow rate in mL/min

P= mean plasma radioactivity in counts/min/mL

SA= body surface area in m2

Radiation Dosimetry The estimated absorbed radiation doses to an average (70 kg) patient from an

intravenous dose of 100 µCi (3.7 megabecquerels) of GLOFIL-125 are shown in

Table 4. Calculations assume that there is 1% free iodide in the preparation and that

the thyroid uptake of the iodine is 25%.
Jeanatope

Jeanatope

Radioiodinated serum albumin is administered intravenously. When a

procedure such as a blood volume determination is to be repeated, the total

dosage administered in any one week should not exceed 7.4 megabecquerels

(200 microcuries).

To minimise the uptake of radioactive iodine by the thyroid, prior

administration of Lugol's Solution (Strong Iodine Solution USP) may be used.

Ten drops of Lugol's Solution three times a daily, beginning at least 24 hours

before administration of Iodinated Serum Albumin I-125 and continuing for one

or two weeks thereafter, is a suitable dose.

Complete assay data for each vial are provided on the container.

Note: The expiration date given on the container pertains to the biologic

properties of the material and not to the radioactivity label, it is important to

make certain that the radioactivity in the dose at the time of administration is

sufficient for the intended use.
Volumex

Volumex

Volumex (Iodinated I 131 Albumin Injection) is administered intravenously.

Parenteral drug products should be inspected visually for particulate matter and

abnormal coloration prior to administration whenever solution and container per-

mit. Volumex (Iodinated I 131 Albumin Injection) may be colorless to very pale

yellow. Solutions with excessive coloration should not be used.

When a procedure such as a blood volume or a circulation time determination

is to be repeated, the total dosage administered in any one week should not

exceed 200 microcuries.

To minimize the uptake of radioactive iodine by the thyroid, prior administration

of Lugol’s Solution (Strong Iodine Solution USP) may be used. Ten drops of

Lugol’s Solution three times daily, beginning at least 24 hours before administra-

tion of Volumex and continuing for one or two weeks thereafter, is a suitable

dose.

Complete assay data for each single unit dose are provided on the container.

Note: The expiration date given on the container pertains to the biologic

properties of the material and not to the radioactivity level. It is important to make

certain that the radioactivity in the dose at the time of administration is sufficient

for the intended use.

The patient dose should be measured by a suitable radioactivity calibration

system immediately prior to administration.

Note: A shielded syringe may be used for withdrawing and injecting the

iodinated I 131 albumin.

Total Blood and Plasma Volumes

Dosage may range from 5 to 50 microcuries.

Blood Volume Determination

A. Reference Solution

Reference solution is provided with each single unit dose of Volumex. Determine

the radioactivity concentration (net cpm/mL) of the reference solution. Care must

be taken to assure that the reference solution and the blood samples (Step B3)

are assayed using the same geometric configuration.

B. Administration of Dose

1. After withdrawing a background blood sample as described below, insert an

intravenous (IV) line into a large vein in patient’s arm. Inject the entire

Volumex dose (one milliliter) through the IV line for immediate delivery.

Measure the residual radioactivity in the syringe and needle.

2. Destroy syringe after injecting. Do not attempt to resterilize. CAUTION: The

syringe should be disposed of in accordance with the US Nuclear Regulatory

Commission or Agreement State regulations pertaining to the disposal of ra-

dioactive waste.

3. At 12, 18, 24, 30 and 36 minutes after injecting the dose, withdraw blood

samples from the patient with a sterile syringe or evacuated

sample tube containing anti-coagulant.

C. Calculation of Blood Volume

1. Take a known aliquot from each blood sample and determine radioconcentration

in net cpm/mL.

2. Plot the 12, 18, 24, 30 and 36 minute sample counts (net cpm/mL) on semilog-

graph paper using the average count value of each sample and determine the

radioconcentration at injection time (zero time) by drawing a straight line through

the 12, 18, 24, 30 and 36 minute points to zero time. The x ordinate of the

graph is the sample withdrawal time and the logarithmic y ordinate is

radioconcentration in net cpm/mL.

3. Calculate patient’s blood volume (in mL) using the following formula:

Net cpm/mL reference solution bloodNet cpm/mL patient’s blood sample x DF = volume (in mL)

Sample Blood Volume Calculations

Volume of Blood sample aliquot = 1.0 mL

Volume of Reference Solution aliquot = 1.0 mL

Net counts at zero time = 48,100

Net counts obtained from reference solution aliquot = 52, 430

If, for example, DF, dilution factor of the reference solution = 4000

Using the above formula gives = 52,430 x 4000 = 4360 mL

48,100

Serial Blood Volume Determinations

Iodinated I 131 Albumin Injection is administered in sufficiently low dosage to permit

repetitions as often as required by clinical circumstances. It must be remembered

that it is always necessary to correct for background radioactivity remaining in the

blood from former determinations. Therefore, for each determination after the first

one, a background blood sample must be taken just before the iodinated I 131

albumin is injected.

Background Blood Sample

1. Withdraw background blood sample from large vein in patient’s sampling arm

with a sterile syringe or evacuated sampling tube containing anti-coagulant.

2. Leaving needle in patient’s vein, detach syringe containing blood sample.

3. Attached syringe containing the dose of Volumex to the indwelling IV line

and administer (see instructions under Blood Volume Determination,

Administration of Dose).

4. Determine radioconcentration in net cpm/mL of aliquots taken from back-

ground and postinjection blood samples, and from the reference solution.

The radioconcentration (net cpm/mL) per aliquot of the background blood

sample must be subtracted from the radioconcentration per aliquot of the blood

sample obtained after the injection of iodinated I 131 albumin. The formula

for calculating each blood volume determination after the first one thus becomes:

Net cpm/mL reference solution blood x DF = blood

Net cpm/mL Net cpm/mL volume

postinjection minus background (in mL)

blood sample blood sample

Plasma Volume Determination

The procedure is essentially the same as that for blood volume determination,

except that the blood sample drawn from the patient is centrifuged, the red blood

cells are removed, and net cpm/mL of the plasma is determined. The formula for

calculation of plasma volume, therefore is:

Net cpm/mL reference solution x DF = plasma

Net cpm/mL patient’s plasma sample volume

(in mL)

Protein Turnover Studies

Dosages used have ranged from 10 to 150 microcuries. After injection, a period

of seven days should be allowed before determinations are made to permit the

elimination of any degraded protein in the dose.

Radiation Dosimetry

The estimated absorbed radiation doses to an average patient (70 kg) from an

intravenous injection of 50 microcuries of Iodinated I 131 Albumin Injection USP

are shown in Table 4.

For doses of 10, 25, 75, 150, 500 and 750 microcuries, the estimated absorbed

doses are 0.2, 0.5, 1.5, 3, 10 and 15 times the number of rads given, respectively.
Megatope

Megatope

Megatope (Iodinated I 131 Albumin Injection) is administered intravenously. Parenteral

drug products should be inspected visually for particulate matter and abnormal

coloration prior to administration whenever solution and container permit.

Megatope (Iodinated I 131 Albumin Injection) may be colorless to very pale yellow.

Solutions with excessive colorations should not be used.

When a procedure such as blood volume or a circulation time determination is to

be repeated, the total dosage administered in any one week should not exceed 200

microcuries.

To minimize the uptake of radioactive Iodine by the thyroid, prior administration of

Lugol's Solution (Strong Iodine Solution USP) may be used. Ten drops of Lugol's

Solution three times daily, beginning at least 24 hours before administration of

Megatope and continuing for one or two weeks thereafter, is a suitable dose.

Complete assay data for each vial are provided on the container.

Note: The expiration date given on the container pertains to the biologic properties

of the material and not to the radioactivity level. It is important to make certain that the

radioactivity in the dose at the time of administration is sufficient for the intended use.

The patient dose should be measured by a suitable radioactivity calibration system

immediately prior to administration.

Note: A shielded syringe should be used for withdrawing and injecting the iodinated

I 131 albumin

Total Blood and Plasma Volumes

Dosage may range from 5 to 50 microcuries.

Blood Volume Determination

A. Preparation of Reference Solution

Remove an aliquot of the contents of the vial to be used in the procedure identical in

volume to the dose to be administered to the patient. Prepare a reference solution

using normal saline as a diluent. The recommended dilution is 1:4000 [Dilution Factor

(DF) = 4000]. Determine the radioactivity concentration (net cpm/ml) of the

reference solution. Care must be taken to assure that the reference solution and the

blood samples (Step B3) are assayed using the same geometric configuration.

A. Administration of Dose

1. Inject the dose into a large vein in patient's arm. Measure the residual radioactivity

in the syringe and needle.

2. Destroy the syringe after injecting. Do not attempt to resterilize.CAUTION: The

syringe should be disposed of in accordance with the US Nuclear Regulatory

Commission or Agreement State regulations pertaining to the disposal of

radioactive waste.

3. At 5 and 15 minutes after injecting the dose, withdraw blood samples from the

patient's other arm with a sterile heparinized syringe.

B. Calculation of Blood Volume

1. Take a known aliquot from each blood sample and determine radioconcentration

in net cpm/mL.

2. Plot the 5- and 15-minute sample counts (net cpm/mL) on semilog graph paper

using the average count value of each sample and determine the

radioconcentration at injection time (zero time) by drawing a straight line through

the 15- and 5- minute points to zero time. The x ordinate iof the graph is the sample

withdrawal time and the logarithmic y ordinate is radioconcentration in

net cpm/mL.

3. Calculate the patient's blood volume (in mL) using the following formula:

Net cpm/mL reference solution × DF = blood volume (in mL)

Net cpm/mL patient's blood sample

Sample Blood Volume Calculations

Volume of blood sample aliquot = 1.0 mL

Volume of reference solution aliquot = 1.0 mL

Net counts at zero time = 48,100

Net counts obtained from reference solution aliquot = 52,430

Using the formula above gives 52,430 x 4000 = 4360 mL 48,100

Serial Blood Volume Determinations

Iodinated I 131 Albumin Injection is administered in sufficiently low dosage to permit

repetitions as often as required by clinical circumstances. It must be remembered that

it is always necessary to correct for background radioactivity remaining in the blood

from former determinations. Therefore, for each determination after the first one, a

background blood sample must be taken just before the iodinated I 131 albumin is

injected.

Background Blood Sample:

1. Withdraw background blood sample from large vein in patient's arm with a sterile

heparinized syringe.

2. Leaving needle in patient's vein, detach syringe containing blood sample.

3. Attach syringe containing the dose of Megatope to the indwelling needle and

administer (see instructions under Blood Volume Determination, Administration of

Dose).

4. Determine radioconcentration in net cpm/mL of aliquots taken from background

and postinjection blood samples, and from the reference solution.

The radioconcentration (net cpm/mL) per aliquot of the background blood sample

must be subtracted from the radioconcentration per aliquot of the blood sample

obtained after the injection of Iodinated I 131 albumin. The formula for calculating

each blood volume determination after the first one thus becomes:

Net cpm/mL reference solution × DF = bloodNet cpm/mL Net cpm/mL volumepostinjection minus backgroundblood sample blood sample (in mL)

Plasma Volume Determination

The procedure is essentially the same as that for blood volume determination, except

that the blood sample drawn from the patient is centrifuged, the red blood cells are

removed, and net cpm/mL of the plasma is determined. The formula for calculation of

plasma volume, therefore is:

Net cpm/mL reference solution × DF = plasma volume Net cpm/mL patient's plasma sample (in mL)

Cardiac Output

Dosage generally ranges from 3 to 50 microcuries.

Cardiac and Pulmonary Blood Volumes; Circulation Times

Dosages used have generally been 75 to 130 microcuries.

Protein Turnover Studies

Dosages used have ranged from 10 to 150 microcuries. After injection, a period of

seven days should be allowed before determinations are made to permit the

elimination of any degraded protein in the dose.

Heart and Great Vessel Delineation

The suggested dosage is 5 microcuries per kg of body weight, although doses up to

750 microcuries have been used, depending on the instrumentation available and the

scanning technique employed.

Localization of the Placenta

For localization of the placenta in the differential diagnosis of placenta praevia, a 3 to 5

microcurie dose is recommended; this dose has proved adequate for excellent

localization, and the fetal total body radiation is a fraction of that received during x-ray

placentography. While fetal thyroid irradiation is higher with Iodinated I 131 Albumin

Injection than with x-ray placentography, the administration of Lugol's Solution is

reported to eliminate this hazard.

Localization of Celebral Neospasms

The suggested dosage is 5 microcuries per kg of body weight. Although doses as

large as 500 microcuries of Iodinated I 131 Albumin Injection have been used, the

dose should be kept as small as possible. Dosage is administered six hours before the

initial examination, and scans are repeated at periodic intervals.

Radiation Dosimetry

The estimated absorbed radiation doses to an average patient (70 kg) from an

intravenous injection of 50 microcuries of Iodinated I 131 Albumin Injection USP are

shown in Table 4.

Iso-tex Diagnostics, Inc.

Manufacturer Details

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Iso-tex Diagnostics, Inc. Drugs