Abstracts of Posters Presented at the International Anesthesia Research Society; 72nd Clinical and Scientific Congress; Orlando, FL; March 7-11, 1998: Ambulatory Anesthesia
INTRODUCTION: It is predicted that by the year 2000 75% of all elective surgery will be performed on an outpatient basis. Concurrently, an increasing number of these patients with be elderly and have co-existing medical diseases. Anesthesiologists will more frequently be faced with day-of-surgery dilemmas regarding the adequacy of preoperative testing, or whether a patient's postoperative condition is adequate for safe discharge home. In these three reports, we describe the value of perioperative transthoracic echocardiography (ECHO) in the decision-making process.
METHODS: Case #1 A 67 year old woman presented for right knee arthroscopy. Despite insignificant past medical history (PMH) of cardiovascular disease, auscultation of the heart revealed a loud, harsh systolic munnur. Repolarization abnormalities and left ventricular hypertrophy (LVH) were evident on her EKG. Rather than postpone surgery for additional testing, ECHO was performed, revealing only senile aortic calcification, good left ventricular function and absence of significant aortic stenosis by Doppler (Figure 1), it was decided to proceed with the operation under spinal anesthesia. Her perioperative course was uneventful.
Case#2 A 65 year old smoker with arterial hypertension was scheduled for transurethral bladder tumor resection (TURBT). The patient reported poor exercise tolerance, but had no PMH of lung or heart disease, and no signs of congestive heart failure. His EKG was consistent with LVH. An ECHO performed in the holding area demonstrated mild LVH with an ejection fraction of 65% and absence of regional wall motion abnormalities (WMA). The surgery proceeded uneventfully under spinal anesthesia, and the patient was discharged home following his recovery in the postoperative care unit (PACU).
Case#3 A 75 year old man with arterial hypertension, well controlled with hydrochlorothiazide 25 mg (Hctz), presented for TURBT. His preoperative blood pressure was 175/95 mmHg and the EKG showed LVH. The introduction of spinal anesthesia (75 mg of hyperbaric lidocaine in the sitting position) resulted in hypotension requiring multiple boluses of ephedrine and phenylephrine. Although the operation ended uneventfully, he remained dependent on intermittent doses of vasopressors in the PACU. ECHO was performed at this time revealing severe concentric LVH, and absence of WMA (Figure 2). Subsequently, administration of 750 ml of isotonic saline promptly corrected his episodic hypotension. His internist was notified of the findings, the Hctz was discontinued, and the patient was discharged home.
DISCUSSION Despite attempts to carefully prescreen and optimize patients scheduled for ambulatory surgery, many patients with significant PMH "slip through the cracks". Often surgeons fail to recognize existing medical problems, or internists have inadequate understanding of the interaction of medical disease with the stresses of anesthesia and surgery. Occasionally patients do not comply with the recommended preoperative screening. The rapidly changing health care environment and the shift toward outpatient surgery demands modification in the practice of anesthesiology. In addition to providing anesthesia, anesthesiologists are now often called upon to assume new responsibilities and act as perioperative physicians for patients with coexisting diseases presenting for same-day surgery. As more anesthesiologists gain expertise in the use of echocardiography, this expertise can become a valuable adjunct in the perioperative management and clinical decision making process in the same-day surgery setting.