May/June 2004 7

Introduction

The past few decades have witnessed an exponentialleap in the sophistication and variety of surgical care avail-able to companion animals. There is probably a veterinarycounterpart to almost every procedure currently performedin human patients.

Total hip replacements are now routine procedures formany veterinary surgeons. One institution is now offeringtotal elbow replacements for canine patients suffering fromdebilitating arthritis of the elbow joint. While dogs tendnot to suffer from coronary artery disease, there are nowmany cardiovascular surgeries performed on veterinarypatients including open heart procedures such as valvereplacements and septal defect repairs (holes in the heart)and closed heart procedures such as pacemaker implanta-tion, patent ductus arteriosus (PDA) repair, and heart basetumor removals.

Highly technical procedures are now available to cor-rect anomalies of the urinary system, the digestive system,the nervous system, the respiratory system, the musculo-skeletal system and virtually all others.

Tremendous progress has been achieved in the surgicalbattle against all forms of cancer in companion animalsfrom limb-sparing techniques for the treatment ofosteosarcoma to computer guided surgery for the removalof brain tumors.

Kidney transplants are now performed on felines inseveral hospitals throughout the world. These patients aregenerally older cats in some form of renal (kidney) failure.The owners choosing a transplant must adopt a compatibledonor cat which has been slated for euthanasia from a shel-ter and then agree to provide a home to the donor cat forthe rest of its life. After transplantation the recipient cat isplaced on anti-rejection drugs as in humans. Many of thesepatients survive several years with a good quality of life.

Kidney transplants are possible in dogs but very fewhave been performed clinically. It is much more difficult toimmunosuppress the rejection response in dogs even whendonors are closely matched or related. The technology forheart and liver transplants in dogs also exists. In fact,canines have served as the model for the development ofthese procedures in man. They are not performed clinical-ly in dogs because of donor controversy. Both proceduresrequire the death of the donor, and suitable brain-deaddonors are rare in veterinary medicine.

Modern diagnostic equipment such as ultrasoundimaging equipment, CAT (computer-assisted tomography)scanning equipment, and MRIs (magnetic resonance imag-ing machines) are now available through many veterinarycenters to assist in establishing a diagnosis and monitoringthe progression of diseases and/or their treatments.

Virtually any surgical procedure now available tohumans could theoretically be offered to feline and caninepatients. In many cases, however, cost is the limiting factor.

It would be well beyond the scope of this article to dis-cuss the many specific surgical procedures now available insmall animal practices. Indeed, multi-volume textbooksare devoted to just that. However two general areas of vet-erinary surgery that have become quite common deservefurther discussion. They are laser surgery and minimallyinvasive surgery.

Laser Surgery

Veterinary surgical lasers have become very popularover the past several years. Medical use of the laser beganin the early 1960s. The first units were costly, non-portable, and had huge maintenance and operational prob-lems. Improvements in laser development in the militaryand industry benefited the biomedical lasers which soonbecame more user friendly.

Laser is an acronym for Light Amplified byStimulated Emission of Radiation. Very basically, a laserbeam is created by passing light through a lasing medium.The lasing medium is a solid crystal, a liquid, or most com-monly a gas such as carbon dioxide (CO2). Atoms in thelasing medium are then excited and gain energy after whichthey pass through a partially reflective mirror at one end ofthe laser chamber as a highly concentrated, precise beam oflight. This beam is capable of vaporizing tissues.

Use of laser energy for surgery has many proposedadvantages. Hemostasis (control of bleeding) is excellentwith laser surgery. While blood loss is generally not a prob-lem in most procedures, having a clear and dry surgicalfield is desirable for visualization. The vaporization of tis-sues at the incision site seals nerve endings and blood ves-sels and might result in less post-operative pain andswelling although this has not been fully documented inveterinary patients.

Research studies have proven that laser-created woundstend to heal somewhat slower and are slightly more suscep-tible to infections than scalpel created wounds. When an

Modern Advances in Veterinary Surgery

This month guest columnist Stephen H. Levine, DVM, MS presents the second in his series of articles on surgery.