Renal cancer. Contemporary management. Editor John A. Libertino. Springer New York 2013.
Minimally invasive partial nephrectomy
When planning for LPN or RALPN, careful consideration must be given to appropriate patient selection. A thorough history and physical examination to identify any factors that may impede a laparoscopic approach is necessary. Prior abdominal surgery is not a contraindication to laparoscopic surgery, but care should be taken as extensive intra-abdominal adhesions may be encountered. The surgeon should consider the proximity of the scar to the initial access site and surgical field as well as the nature of the prior surgery, i.e., suppurative processes where there is likely to be adhesion formation. Obese patients may pose additional difficulties as the anatomic landmarks may be shifted and obesity is associated with an increased number of comorbidities. Studies have demonstrated that laparoscopic (transperitoneal or retroperitoneal approach) renal surgery can be performed safely and without increased morbidity in obese patients. Pulmonary and cardiac disease may prevent patient tolerance of pneumoperitoneum. Patients with severe chronic obstructive pulmonary disease are at risk for developing severe hypercarbia with resultant acidosis. The increased intraabdominal pressure induced by peritoneal insufflation is transmitted to the thoracic cavity decreasing cardiac performance. The potential for conversion to an open procedure should be discussed with every patient. All patients receive preoperative bowel preparation with magnesium citrate and a clear liquid diet the day prior to planned surgical procedure.
Imaging should be carefully reviewed to identify number of vessels, exact tumor location, and its proximity to the collecting system, along with the presence of lymphadenopathy. We prefer dedicated cross-sectional imaging (CT scan or MRI) with three-dimensional reconstruction to better assess precise tumor location as well as vascular anatomy. Calculation of RENAL nephrometry score may provide a standardized system of classifying the complexity of renal lesions, useful for research purposes.
After initiation of general endotracheal anesthesia, it is the authors’ preference to place an ipsilateral ureteral catheter in patients prior to proceeding with MIPN. The ureteral catheter allows for retrograde injection of dilute methylene blue during the case for identification and closure of the collecting system. Alternatively, Bove et al. demonstrated no difference in terms of postoperative urine leak rate whether a ureteral catheter was used during LPN. The patient is then placed in a 45° modified flank position (transperitoneal approach) or full flank position (retroperitoneal approach) with the table maximally flexed. The ipsilateral arm and contralateral arm are placed on padded arm boards parallel to the floor in such a position to avoid stretching of the brachial plexus. An axillary roll is used in nearly all patients except the morbidly obese with a significant axillary fat pad. Pillows are placed between the legs with the contralateral leg bent to 90° and ipsilateral leg straight. Careful padding of all bony prominences (hips/knees/ ankles) is performed as needed. Sequential compression devices are routinely utilized on the bilateral lower extremities. Flank and shoulder supports are placed on the posterior aspect to allow table rotation. The hips and shoulders are secured with tape to the table to ensure no movement with table rotation. Neutral positioning of the head is confirmed. A universal time-out involving all team members is performed after positioning and prior to draping to ensure correct laterality. Careful patient positioning is paramount to prevent neuropathies and rhabdomyolysis (Фиг. 14.1). Despite proper positioning, rhabdomyolysis has been reported [29, 30]. The patient’s abdomen and flank are prepped widely in preparation for efficient conversion to open surgery if needed.