MP30-12 POST PERCUTANEOUS NEPHROLITHOTOMY, WHAT DEFINES CLINICAL INSIGINIFICANT RESIDUAL FRAGMENTS

Abstract

INTRODUCTION AND OBJECTIVES: Tools and equipment utilized during endourologic surgery contribute significantly to noise pollution in the operating room (OR) during percutaneous nephrostolithotomy (PCNL). The purpose of this study was to determine OR baseline noise and noise contributed by endourologic equipment during PCNL; then, to determine the effect of this noise upon the effectiveness of communication. METHODS: Ambient noise in the operating room was measured using a digital decibel meter. Noise levels were determined by the sequential addition of normal conversation, highpressure suction, ultrasonic lithotripter, and background music. Three subjectsdthe surgical assistant (0.8m from the surgeon), anesthesiologist (1.8m), and the circulator (2.5m) were placed in the operating room to simulate positioning during PCNL. Five trials of 20 different medical words/phrases were spoken by the surgeon. Trials were performed with three sound categories. The first category included ambient sound alone, the second included ambient sound, suction and lithotryptors, and the third included ambient sound, suction, lithotripsy and loud music. In addition, the OR noise was compared to commonly encountered environmental noise; including cars (n1⁄412) and trucks (n1⁄418) driving 40 mph at 30 ft, and freight trains (n1⁄48) traveling 55 mph at 30 and 45 feet. Statistical analyses were performed using a student t-test. RESULTS: The average baseline noise was 53.49dB(A). As conversation, suction/lithotripsy, and music were added, noise levels were 61.82dB(A), 77.96dB(A), and 87.33dB(A), respectively. At baseline noise, the surgical assistant, anesthesiologist and circulating nurse correctly recorded 100%, 100% and 96% of the words, respectively. The correct response rate by the subjects decreased to 97%(p1⁄40.172), 81%(p<0.001) and 56%(p<0.001) with suction/lithotripsy and 90%(p1⁄40.006), 48%(p<0.001) and 13%(p<0.001) with suction/lithotripsy/music. By comparison, total PCNL noise (conversation/suction/lithotripsy/music) [87.33 dB(A)] was louder than the measured car [67.8 dB(A); p<0.001] and pickup truck noise [69.2 dB(A); p<0.001] but similar to a freight train at 30 feet [82.2 dB(A); p1⁄40.44]. CONCLUSIONS: Endourologic instruments and music utilized during PCNL may significantly contribute to noise pollution in the operating room environment and this noise may significantly degrade the effectiveness of communication. An understanding of the role that noise and distance play in affecting the success of communication may reduce operating room errors and patient complications.