Medicine is an ever-changing science. As new research and clinical experience broaden our knowledge, changes in treatment and drug therapy are required. The authors and the publisher o  this work have checked with sources believed to be reliable in their reports to provide information that is complete and generally in accord with the standards accepted at the time o  publication. However, in view o  the possibility o  human error or changes in medical sciences, neither the authors nor the publisher nor any other party who has been involved in the preparation or publication o  this work warrants that the information contained herein is in every respect accurate or complete, and they disclaim all responsibility  or any errors or omissions or  or the results obtained  rom use o  the information contained in this work. Readers are encouraged to con rm the information contained herein with other sources. For example and in particular, readers are advised to check the product information sheet included in the package o  each drug they plan to administer to be certain that the information contained in this work is accurate and that changes have not been made in the recommended dose or in the contraindications  or administration. This recommendation is o  particular importance in connection with new or in requently used drugs.