Surgery STAT: Preoperative assessment of surgical patients

Surgery STAT: Preoperative assessment of surgical patients

A systematic approach can help ensure safety

EDITOR'S NOTE: SurgerySTAT is a collaborative column between the American College of Veterinary Surgeons (ACVS) and DVM Newsmagazine .

Veterinary patients brought in for surgical procedures must be thoroughly evaluated, not only for their presenting complaints and diseases, but also for their suitability as candidates for anesthesia and subsequent surgery. Such an assessment is important for safe anesthetic and surgical practice.

Dr. Abimbola O. Oshin
A thorough evaluation may indicate that further care is necessary in the perioperative period—care that could minimize the risk of surgery and potential for postoperative complications. A good evaluation also helps surgeons determine whether surgery is warranted, as well as select the best procedure for a patient.

Moreover, it helps with prognostication, giving the clients a realistic expectation regarding the surgical intervention. In most cases, a thorough evaluation will also highlight other aspects of a patient's health that may need attention and future management.

All of the elements for a thorough preoperative assessment follow.

History taking

A complete history can be organized in the following manner for ease of remembrance: signalment, chief complaint, history of present illness, history of past illnesses (e.g., medical, surgical, vaccinations, medications), family history (if known), environmental history, diet history and body systems review.

Physical examination

Despite a natural inclination to concentrate on the presenting problems, veterinarians should focus the physical examination on evaluating the whole patient. Vital parameters and a general assessment of the patient, including a body condition score, should be recorded. Indeed, a systematic approach generally ensures that all body systems will be adequately evaluated.

Various formats have been described for performing a thorough physical examination. One format divides the evaluation process into examinations of the head and neck (eyes, ears, nose and throat), forequarters, thorax, abdomen and hindquarters. Another format emphasizes a body system approach, with division of examination into that of the cardiovascular, respiratory, alimentary, urogenital, lymphatic, endocrine, integumentary, musculoskeletal and neurologic systems. Note that a rectal examination is a valuable aspect of the examination and should always be performed.

Whichever system is used, it's imperative for each clinician to establish his or her own pattern so it becomes a routine progression, because haphazard examination always will be deficient in some category.

Of the procedures available for evaluating patients, the history and physical examination, described previously, are most effective in detecting important abnormalities. Problems missed at this stage are usually overlooked when more invasive or expensive diagnostic tests are performed.

Table 1: Physical status in surgical patients
After a complete history is taken and a physical examination is performed, it should be possible to assign a physical status to each patient as listed in Table 1. In emergencies in which a patient's status mandates an abbreviated examination, the physical status is qualified with an "E." To clarify, an emergency is defined as existing when delay in treatment would markedly increase the threat to the patient's life or body part. In such circumstances, only data for immediate initiation of treatment are collected, and the examination is then completed after the animal is stabilized.

Physical status is a major determinant but is not a direct predictor of anesthetic or surgical risk. Rather, the major purpose of discerning physical status is for comparing patients, selecting the most appropriate anesthetic protocol and determining whether a patient's status can be improved by postponing surgery in elective cases.