SECOND MODIFICATION TO LICENSE AGREEMENT


                  THIS AGREEMENT entered into this 30th day of May, 1997 between
DALTEX MEDICAL SCIENCES, INC. (a corporation of the State of Delaware), having a
place of business at 50 Kulick Road, Fairfield,  NJ 07004 ("Licensor") and ARROW
INTERNATIONAL, INC., (a Pennsylvania corporation), having a place of business at
3000 Bernville Road, Reading, PA 19605 ("Licensee").

                  WHEREAS,  Licensor and Licensee have previously entered into a
License Agreement dated the 28th day of March,  1991 ("1991 License  Agreement")
relating to certain technology set forth therein and which remains in full force
and effect;

                  WHEREAS,  Licensor and Licensee have also  previously  entered
into  a  Modification  to  the  1991  License  Agreement  ("First   Modification
Agreement")  regarding  the  payment  of  royalties,  which  First  Modification
Agreement remains in full force and effect; and

                  WHEREAS,  Licensor  and  Licensee,  to their  mutual  benefit,
desire to again  modify the terms of the 1991 License  Agreement  for certain of
the Licensed Products in the Fields of Application.

                  NOW, THEREFORE, in consideration of the above premises and the
mutual covenants and conditions  hereinafter  contained,  and for other good and
valuable consideration,  the receipt and sufficiency of which is acknowledged by
the  execution and delivery  hereof,  the parties  hereby  covenant and agree as
follows:

                  1.       Definitions:  The terms used in this Agreement
shall have the same meaning as those defined in Article 1 of the
1991 License Agreement.

                  2.       Modification to 1991 License Agreement:  The
following paragraphs are hereby added to Article 1(d) (Fields of
Application) of the 1991 License Agreement:

                        (v)     Epidural catheters used to infuse
                                drugs into the epidural  space in
                                the spinal column.

                        (vi)    Implantable  infusion  ports  and
                                pumps    and    their    attached
                                catheters  used for drug  therapy
                                and   access   to  the   vascular
                                system.

                        (vii)   Intra-aortic balloon catheters.

<PAGE>

                        (viii)  Drainage  catheters used to drain
                                chest     cavities,      surgical
                                incisions, wounds and abscesses.

                  3.       Supplemental Modification to 1991 License
Agreement:  The following paragraph is hereby added to Article 1
of the 1991 License Agreement (Definitions):

                  h)       Running royalty rate is defined as Five
                           (5%) Percent of Unit Net Sales of
                           products sold by Licensee which fall
                           within the added Fields of Application
                           (v-viii) set forth above.  For a
                           Licensed Product or Products within the
                           added Fields of Application (v-viii)
                           that is sold together with other non-
                           licensed products in a single package to
                           a customer, the Running royalty rate of
                           Five (5%) Percent shall apply only to
                           the established Unit Net Sales price of
                           the Licensed Product or Products.

                  4.       Payments:  In consideration of the foregoing
additions to the Fields of Application under the 1991 License
Agreement, upon execution of this Agreement, Licensee shall pay
Licensor a one-time, non-refundable, non-creditable fee of One
Hundred Thousand ($100,000.00) Dollars.

                  Upon execution of this Agreement,  and for the first (3) years
thereafter,  Licensor waives  development  fees and minimum annual royalties due
for products  sold by Licensee  falling  under the added  Fields of  Application
(v-viii) set forth above.

                  After the third full year this Agreement is in force, Licensee
shall pay development fees of $2,500.00,  payable quarterly in advance, for each
of the new  Fields  of  Application  (v-viii)  set  forth  above,  during  their
development  phase and prior to  Licensee  sales of  products in each of the new
Fields of Application. Licensee's obligation to pay development fees shall cease
in the  quarter  following  Licensee's  sale of a  product  in each of the added
Fields of  Application.  After such time a sale is made,  Licensee shall pay the
Running  royalty  rate defined  above in Article 3(h) herein,  and at a minimum,
shall pay a minimum royalty of $2,500.00, payable quarterly in advance, for each
of the new Fields of  Application  (v-viii) set forth above.  All payment  terms
herein are effective throughout the remaining term of the 1991 License Agreement
and in accordance  with the payment and recording terms provided in Article 4 of
the 1991 License Agreement.

                  5.       Net Sales:  Net Sales are hereby defined as the
total invoiced amount of all sales by Licensee to the trade, less
cash and trade discounts, returns, allowances, free goods and

                                2

<PAGE>

replacements, taxes applicable to such sales, and government charges assumed and
delivery charges borne by Licensee.

                  6. Best Efforts:  Licensee shall use all reasonable endeavors,
to manufacture,  promote and sell the products with a view to achieving  maximum
benefit in its judgment to the parties hereto, and Licensor shall be entitled to
call for information from time to time on the endeavors being made. In the event
that the Licensor  considers  that  Licensee has failed  properly to comply with
this provision,  or a sub-licensee has so failed, Licensor may give Licensee six
months  notice  (accompanied  by  detailed  reasons  for  its  decision)  of its
intention  to  convert  the  Field  of  Use  to a  non-exclusive  right,  unless
Licensee's,  or sub-licensee's,  performance has been remedied to the reasonable
satisfaction of Licensor.

                  7. The 1991 License  Agreement:  Except as expressly  modified
herein,  the  provisions  of the 1991  License  Agreement  between  Licensor and
Licensee,  and the terms of the  First  Modification  Agreement,  remain in full
force and effect.  In  addition,  this second  modification  to the 1991 License
Agreement  between Licensor and Licensee does not modify or alter the terms of a
Patent  Settlement  Agreement  dated  January 1, 1995,  between the  Trustees of
Columbia  University,  Daltex Medical Sciences,  Inc., Arrow International Inc.,
and Becton Dickinson and Company.

                  THE  PARTIES  have  duly  executed  this  Second  Modification
Agreement in duplicate executed counterparts, effective the first date written.


                                  DALTEX MEDICAL SCIENCES, INC.


                                  By:     /s/Bruce Hausman
May 9, 1997
Date                              Title:     President



                                  ARROW INTERNATIONAL, INC.


                                  By:      Marlin Miller, Jr.
May 30, 1997
Date                              Title:      President


                                        3