- To determine the success of our clinical care pathway for laparoscopic (LPN) and robotic partial nephrectomy (RPN) and to examine factors predictive for success.
body mass index
Charlson comorbidity index
minimally invasive surgery
(laparoscopic) (robotic) partial nephrectomy
The increase in kidney cancer incidence during recent decades continues, reaching an estimated 61 000 new cases in USA during 2011 . With stage migration toward smaller renal masses, nephron-sparing procedures have gained popularity. Equivalent oncological outcomes and potentially improved renal function outcomes have established partial nephrectomy (PN) as a standard treatment for renal masses [2, 3].
Laparoscopic and robotic techniques have been adopted to decrease morbidity and improve quality of life after PN. Early in the learning curve, higher complications rates with laparoscopic PN (LPN) were reported . However, contemporary data suggest that with increased experience, functional outcomes and complication rates for LPN are equal or better than those of the open approach .
Hospitalisation duration can serve as a surrogate for the quality of major procedures . To decrease the morbidity, costs, and hospital stay, recovery pathways have been introduced in various urological procedures, including radical prostatectomy and PN.
We evaluated a care pathway for LPN and robotic PN (RPN). Our care pathway essentials include: non-narcotic analgesic use, early ambulation and regular diet and discharge on postoperative day (POD) 1. We determined success rates of our clinical care pathway, readmission rates, and examined factors predictive of success.
All patients undergoing minimally invasive surgery (MIS) for renal masses are placed on a care pathway for early discharge (Table 1). The main goal of the pathway is to safely discharge the patient home on POD 1. Implementation of the care pathway is initiated at the preoperative clinic visit, where the care plan is thoroughly described to the patient by a physician or physician-extender. On the day of surgery, the care plan is again described by the physician obtaining consent for surgery. Unless contraindicated by allergy, all patients receive 5000 units heparin (s.c.) before incision and every 8 h postoperatively while in the hospital. Postoperatively, patients are given a regimen of acetaminophen (650 mg every 6 h) and ibuprofen (400 mg every 6 h) or i.v. ketorolac for pain control. If the GFR is <60 mL/min/1.73 m2, ibuprofen and ketorolac are not used and patients are given intermittent doses of i.v. narcotics. We obtain a complete blood count and basic metabolic panel in the post-anaesthesia care unit and repeated these studies early on POD 1. If the patient is stable after transfer from the recovery room to a regular nursing unit, they are encouraged to sit in a chair and subsequently ambulate. Patients receive a light meal on the evening of surgery consisting of liquids and soft diet. The urethral catheter is removed at 0600 h on POD 1. The patient is encouraged to ambulate for 15 min every 2 h on the morning of POD 1. If the drain output remains at <80 mL per 8-h shift, it is typically removed. For higher drain outputs, laboratory assessment of the drain fluid is obtained. Patients are discharged home on a regimen of ibuprofen and acetaminophen for pain control with tramadol, as needed. Successful care pathway implementation is defined as patient discharge anytime during the first day after surgery.
|Care plan is thoroughly described to the patient by a physician or physician-extender during clinic visit and again at the day of surgery.|
|s.c. heparin (5000 units) is given prior to incision.|
|Postoperative (day 0)|
|CBC and BMP.|
|If stable, patient is transferred to a regular nursing unit.|
|Acetaminophen (650 mg every 6 h) and ibuprofen (400 mg every 6 h) or i.v. ketorolac. If GFR <60 mL/min/1.73 m2, intermittent doses of i.v. opioids were used instead.|
|Ambulation and alimentation (liquids and soft diet).|
|Postoperative (day 1)|
|CBC and BMP|
|Removal of urethral catheter (at 0600 h)|
|Continues ambulation (for 15 min every 2 h)|
|Removal of drain (if <80 mL per 8-h shift)|
|Discharge with analgesics regimen (ibuprofen and acetaminophen ± tramadol)|
After obtaining Institutional Review Board approval, we retrospectively queried our prospectively maintained MIS renal mass database to identify the study sample. We included all patients who underwent LPN or RPN from 2003 to 2010. We excluded patients who had undergone ablative treatments, i.e. laparoscopic-assisted cryoablation or radiofrequency ablation.
We divided the cohort into two groups: those discharged on POD 1 (care pathway achieved) and those discharged after POD 1 (care pathway not achieved). We examined patient-related factors including age, gender, race, body mass index (BMI), age-adjusted Charlson comorbidity index (CCI), smoking status, previous abdominal surgery, tumour laterality, tumour location, tumour size, preoperative haematocrit and renal function. We examined surgical factors including operating time, estimated blood loss, warm ischaemia time, nadir haematocrit, postoperative renal function, blood transfusion, and perioperative complications. Perioperative complications were stratified according to Clavien-Dindo classification . Additionally, we examined case time, to determine if morning cases had different discharge patterns than afternoon cases. We also divided the cohort into initial experience (2003–2006) and contemporary experience (2007–2010) to determine if our institutional experience improved discharge success over time.
The primary outcome was defined as patient discharge on POD 1. We studied secondary outcomes, i.e. readmission rates, complications and factors related to early discharge.
Descriptive statistics were used to summarise patient and surgical factors. Univariate analysis was used to identify factors associated with care pathway success. We fitted forward stepwise multivariate logistic regression models to test the associations of patient-related and surgical factors to the primary endpoint of discharge on POD 1. We secondarily performed a subset analysis on the contemporary cohort to determine which covariates were associated with early discharge in this group. Age, BMI, tumour size, preoperative haematocrit, preoperative renal function, surgery time, estimated blood loss, warm ischaemia time, nadir haematocrit, postoperative serum creatinine were analysed as continuous variables. Gender, smoking status, previous abdominal surgery, tumour laterality, tumour location, case time (am vs pm), surgical period (early cohort vs late cohort), blood transfusion, and perioperative complication were used as dichotomous covariates, whereas race was divided into three categories. The chi-squared test was used for categorical variables, the Mann–Whitney U-test was used to compare medians, and the t-test was used to compare means of continuous variables with normal distribution. MedCalc® (version 12.0 Ostend, Belgium) was used to perform all statistical analyses with a two-sided P < 0.05 considered to indicate statistical significance.
We identified 263 patients that underwent MIS PN from 2003–2010 at our institution by two surgeons (A.L.S. and seE.). RPN represented 17% (46/263) of the total cohort. Overall, 157 (60%) had successful pathway implementation and were discharged on POD 1. The median (interquartile range) length of stay was 1 (1–2) days.
|Patient factors||Overall||Care pathway achieved||Care pathway not achieved||P|
|Total patients, n (%)||263||157 (60)||106 (40)|
|Male, n (%)||153 (58)||99 (63)||54 (51)||0.07|
|Female, n (%)||110 (42)||58 (37)||52 (49)|
|Median (IQR) age, years||59 (50–65)||57.0 (46.0–63.0)||62.0 (53.0–68.0)||<0.001|
|Median (IQR) BMI, kg/m2||28 (25–33)||28 (25–33)||29 (25–34)||0.63|
|Median (IQR) CCI||4 (3–5)||3.0 (3.0–4.0)||4.0 (3.0–6.0)||<0.001|
|Previous abdominal surgery, n (%)|
|Yes||123 (47)||62 (39)||61 (58)||0.006|
|No||140 (53)||95 (61)||45 (42)|
|Tumour laterality, n|
|Tumour location, n|
|Tumour location, n|
|Tumour location, n|
|Median (IQR) preoperative haematocrit, %||40.3 (37.2–43.0)||41.0 (37.9–43.8)||39.3 (36.2–41.6)||0.003|
|Median (IQR) GFR, mL/min/1.23 m2||95.7 (70.6–116.8)||102.1 (79.3–123.3)||87.2 (63.5–108.7)||0.002|
|Mean (95% CI) tumour size, cm||3.0 (2.8–3.2)||3.0 (2.7–3.3)||3.0 (2.8–3.3)||0.73|
On univariate analysis, lower mean age was associated with successful care pathway (54.9 vs 60.9 years; P < 0.001). Caucasians had significantly higher rates of discharge on POD 1 than African Americans (65% vs 45%, P = 0.009). Patients with no prior history of abdominal surgery had higher rates of discharge on POD 1 than those with prior surgery (61% vs 39%, P = 0.006). Preoperative haematocrit and estimated GFR were higher in patients with successful pathway (41.0% vs 39.3%, P = 0.003 and 102.1 vs 87.2 mL/min/1.23 m2, P = 0.002, respectively). Lower median CCI was associated with care pathway success (3.0 vs 4.0, P < 0.001.) Tumour characteristics, including tumour location (anterior/posterior, hilar/lateral, exophytic/endophytic), laterality, and size were not significantly different between the groups (all P > 0.05).
|Surgical factors||Overall||Care pathway achieved||Care pathway not achieved||P|
|Case time, n|
|Morning (am) case||145||94||51||0.13|
|Afternoon (pm) case||115||63||52|
|Case surgical period, n (%)|
|Early cohort, 2003–2006||108||43 (40)||65 (60)||<0.001|
|Late cohort, 2007–2010||155||114 (74)||41 (26)|
|Procedure type, n (%)|
|Robotic||46||30 (65)||16 (35)||0.53|
|Laparoscopic||217||128 (59)||89 (41)|
|Surgery time, min||215 (184.2–247.7)||210 (180–240)||229 (190–252)||0.032|
|EBL, mL||100 (50–200)||100 (50–200)||150 (50–250)||0.003|
|WIT, min||29 (23–33)||28.0 (23–32)||30 (24–35)||0.095|
|Nadir haematocrit, %||33.8 (30.9–36.8)||35.0 (32.0–37.0)||32.0 (28.7–35.7)||<0.001|
|GFR change, mL/min/1.23 m2||–13.1 (–27.1 to 0.0)||–13.3 (–27.5 to 0.0)||–13.1 (–26.0 to 0.0)||0.83|
|Blood transfusion, n|
|Surgical complication, n|
On univariate analysis, surgical period (early: 2003–2006, late: 2007–2010) was associated with successful care pathway as 40% of patients in the early cohort were discharged on POD 1 vs 74% in the late cohort (P < 0.001). Shorter surgical times (210 vs 229 min, P = 0.032), lower estimated blood loss (100 vs 150 mL, P = 0.003) and higher nadir haematocrit (35.0% vs 32.0%, P < 0.001) were associated with successful care pathway. Patients in the successful care pathway group were less likely to have received a perioperative blood transfusion (0% vs 12%, P = 0.001) and less likely to have a perioperative complication (12% vs 32%, P = 0.04). The rate of successful pathway in LPN and RPN cases was 59% and 65%, respectively.
Surgical complications are summarised in Table 4. For the entire cohort, 12 (5%) patients were admitted after discharge. For patients discharged on POD 1, seven (4.5%) were readmitted postoperatively. Causes for readmission in the early discharge group included gross haematuria (three), fever, ileus, anaemia, and acute gout.
|Clavien-Dindo Classification||Care pathway maintained, n||Care pathway not maintained, n|
|Renal vein injury||1||2|
|Thrombosed renal artery||–||1|
|Accessory renal artery injury||1||–|
|Acute renal failure||–||2|
|Acute renal failure||–||1|
On multiple logistic regression with patient-related and surgical factors, only the late surgical period from 2007–2010 (odds ratio [OR] 4.2, 95%CI 2.1–8.4, P < 0.001) was strongly associated with successful discharge on POD 1. Subset analysis on the late surgical period cohort was done to assess for factors influencing early discharge in this group. From this cohort of 155 patients, 114 (74%) patients were discharged on POD 1. On multiple logistic regression analysis, the only factor that remained significant was perioperative complications. Patients without a perioperative complication were more likely to be maintained on the care pathway and discharged on POD 1 (OR 3.2, 95%CI 1.2–9.1, P = 0.021).
After minimally invasive PN, a clinical care pathway with a goal of early discharge is feasible and was achieved in 60% of patients. The success rate increased during the study period, from 40% initially to 74% for more contemporary patients. While numerous demographic, clinical, and surgical factors influenced early discharge, perioperative complications in the contemporary cohort precluded early discharge. Overall 30-day readmission rate for patients discharged on POD 1 was 4.5%, similar to previous reports and helps to dampen the concern that earlier discharge may be associated with an increased readmission rate [8, 9].
Whereas the surgical approach to PN has evolved during the last decade, little has been published about postoperative care modifications. Several factors affect recovery after renal surgery, including level of pain, bowel function, respiratory function, ambulatory capacity and morbidity . Care pathways are designed to reduce the impact of these factors on the postoperative course. A fast-track programme after open PN has been proposed by Chughtai et al. . Based on the principles of early ambulation and diet, as well as coordinated expectations, 60% of patients achieved a target discharge on ≤3 days without an increase in complication or readmission rates.
Laparoscopic renal surgery has significant advantages over open surgery, most prominently due to decreased pain and quicker return to normal activity . While the length of stay after open PN is usually 5–8 days, a shorter stay of 3–5 days after LPN and RPN has been reported [11-14]. Our experience shows the benefits of MIS can be optimized even further, with avoidance of narcotics and their potential side-effects including bowel impairment and delayed convalescence. Initiation of a soft diet and return to an upright position (sitting or standing) on the evening of surgery is successfully implemented in stable patients. Removal of the urinary catheter followed by drain removal on POD 1 increases mobility and facilitates patient readiness for discharge home. To ensure safety, standard blood tests are repeated on POD 1 and the urinary catheter and drain output is monitored until removal. These clinical milestones, in conjunction with appropriate patient counselling, allow for early patient discharge on POD 1.
Several factors may have contributed to the improved success of our pathway in the recent years (Fig. 1). With increasing experience, there has been a decrease in the perioperative complications rate (27% in early period vs 15% in late period). This factor was associated with success rate in the general cohort as well as in the contemporary cohort. Since 2009, robotic surgery has been increasingly used for PN in our institution. Shorter hospital stay has been reported for RPN compared with LPN [15, 16], despite the advantages of MIS being similar for both approaches. We suspect patients' perception of MIS in the robotic surgery era may contribute to pathway implementation. Supporting this, in a recently published cohort of 150 RPN, Abaza et al.  reported that 97% of the patients stayed for a single night and that readmission rate was 2.7%. High expectations from robotic surgery were previously shown in patients undergoing radical prostatectomy [18, 19].
There are several limitations of the present study. Due to its retrospective nature, we were unable to indicate specific modifications to the pathway over the study years. Thus, the contribution of specific pathway components could not be assessed. Additionally, we were unable to produce a morphometry score because a substantial number of imaging studies were not available for review. In the absence of randomisation, successful pathway implementation may have been the result of patient expectations, surgeon, era, or other confounding factors. Finally, we did not perform cost analysis that might have emphasised the economic implications of our pathway.
In conclusion, the present study shows that a care pathway for early discharge after minimally invasive PN can be successfully implemented and does not appear to increase complication or readmission rates. Care pathway implementation and success improves with institutional experience.