after the increasing use of laparoscopy , robotic surgery has provided a new era in minimally invasive surgery . safety and clinical outcomes have been reported in various fields .
the most common complications include ileus , deep vein thrombosis , and pulmonary embolism [ 1 , 2 ] .
however , postoperative acute renal failure ( arf ) is a rare complication in laparoscopic surgery and has not been reported in robotic surgery .
herein we report a case of postoperative acute renal failure in a patient who had undergone robot - assisted prostatectomy .
a 63-year - old man presented with adenocarcinoma of prostate , clinical stage t1c , preoperative serum psa level 7.21  ng / ml , gleason score 3  +  2 , and serum creatinine level 1.3  mg / dl and underwent a robot - assisted prostatectomy .
the patient was placed in the trendelenburg position at an angle of 30 from the horizontal with the legs split .
the operation time was 400  min and intraoperative blood loss was less than 100  ml . throughout the operation
the end - tidal carbon dioxide ( co2 ) level was maintained between 37 and 38  mmhg .
there was a mild increase in abdominal drainage levels to 500  ml per day .
bilateral percutaneous nephrostomy tubes were placed , and patent ureters without urine extravasation found in antegrade pyelography .
the serum creatinine level rose to 3.8  mg / dl 12  h after operation .
pulmonary edema developed on the first postoperative day and the patient received hemodialysis and intensive care .
acute respiratory distress syndrome developed and consequently resulted in duodenal ulcer bleeding despite the use of antacid .
renal function recovered after comorbidity was controlled 2  months after surgery while serum creatinine level was 2.0  mg / dl .
serum creatinine level was 2.0  mg / dl and psa level was less than 0.01  ng / ml after one - year follow - up .
robotic surgery adds a new dimension to this field and provides three - dimensional visualization and allows advanced freedom of instrumentation motion .
currently there are four systems being used to treat patients and the numbers are increasing .
the physiological effects of robotic surgery on the human body are similar to those of laparoscopy assisted surgery [ 1 , 2 ] .
deterioration of renal function after laparoscopic surgery has been reported in various fields , including cholecystectomy , nephrectomy , and bariatric surgeries [ 47 ]
. the common mechanisms of complications are related to : ( 1 ) increased intra - abdominal pressure ( iap ) , ( 2 ) co2 insufflation and ( 3 ) rhabdomyolysis syndrome . to obtain adequate working space , maintaining pneumoperitoneum status
the increased iap is associated with decreased urine output and deterioration of renal function in animal models and humans [ 69 ] .
the major physiological effects of increased iap are direct renal parenchymal and vessel compression and decrease of renal arterial supply and venous drainage [ 8 , 9 ] .
this consequently stimulates the renin , aldosterone , and angiotensin systems , enhances renal vasoconstriction and decreases renal blood flow .
insufflation with co2 may depress myocardial contractility through blood absorption effects and increase systemic vascular resistance , which results in a decrease in cardiac output and activates the renin - angiotensin system .
both iap and insufflation with co2 increase plasma renin and angiotensin ii and subsequently cause reduction of renal blood flow and deterioration of renal function . in our case , oliguria was found 6  h postoperatively at a rate of 20  ml / h .
concluded that the predisposing risk factors included diabetes , hypertension , exaggerated surgical position , body shape character ( muscular frame or morbid obesity ) , hypovolemia , operation time of more than 5  h , and preexisting renal dysfunction . in their study , they found the serum creatinine kinase ( ck ) level to be elevated to more than 5,000 
u / l in all seven patients . compared to our patient , the ck level was 1,831 
there is no strong correlation between ck and arf from literature review , and the possibility of rhabdomyolysis in this patient should still be considered . in conclusion , we report the first case of acute renal failure after robot - assisted radical prostatectomy .
the treatment outline included fluid balance , electrolyte correction , and prevention of secondary complication .
patients with prolonged surgery ( > 5  h ) , morbid obesity , and pre - existing renal function impairment are at higher risk of the development of rhabdomyolysis . minimizing the operation time , adequate patient padding , and intraoperative circulation maintenance are helpful in the prevention of postoperative acute renal failure .
 robot - assisted surgery has been used widely in urological surgery since 2000 . in taiwan , 
 robotic surgery started in 2004 and progress has been ongoing since this time . herein we report a case of acute renal failure post robot - assisted radical prostatectomy . 
 the patient received postoperative hemodialysis and intensive care . 
 the renal function recovered to a serum creatinine level of 2.0  mg / dl 2  months after surgical intervention . 
 the renal function was still normal and the psa level was nadir after one - year follow - up . 
 the outcome is encouraging from the point of view of oncology . to our knowledge , this is the first report of postoperative acute renal failure in robotic surgery . 