start at 11:00 A.M. on day 1. Hydration will continue for 
at least 7 days after completion of ifosfamide if 
tolerated. Hydration will not be stopped without 
discussion with Dr. Wilson unless necessary for medical 
indications, e.g., CHF. Lasix may be administered as 
needed to maintain urine output at >150 cc/hour and to 
reduce patient weight gain. Please note that many 
patients will initially gain 5% fluid body weight 
followed by a spontaneous diuresis. During ifosfamide 
administration (days 1-4), urine should be tested for 
hemoglobin daily and if gross hematuria develops, the 
principal investigator should be notified immediately and 
the next dose of ifosfamide held. If gross hematuria 
develops, a three-way Foley catheter is to be inserted 
and continuous bladder irrigation with 1 L/hr normal 
saline continued 24 hours beyond completion of 
chemotherapy (day 4). 
All patients will develop a metabolic acidosis (decreased 
serum CO 2 ) because of a transient proximal renal tubular 
acidosis (H 2 CO 3 loss) and accumulation of the ifosfamide 
by-produce, chlorbacidaldehyde. The serum CO 2 level 
generally begins to fail by the third day of chemotherapy 
and reaches a nadir 3 to 4 days later. When the serum 
CO 2 level falls to 18, the I.V. fluid changes to D5 1/2 NS 
+ 50 meg/L Na H 2 CO 3 . If the CO 2 continues to fall to < 16, 
12 hours later, the I.V. fluid should be changed to D5 1/4 
NS + 100 meg/L Na H 2 CO 3 . The Na 2 C 03 should be removed 
with the CO 2 is stable and > 22 . 
For a serum potassium < 3.5 mmol/L administer 15 mEo 
of potassium I.V. over 1 hour. Recheck serum potassium 
1 hour after completing the potassium infusion and call 
patient's physician for continued hypokalemia. 
Ifosfamide, admixed with 20% MESNA on a weight basis, 
will be administered in 100 ml D5W intravenously over 2 
hours, daily x 4 days, immediately following etoposide. 
Recombinant DNA Research, Volume 16 
[109] 
