Robotic assisted laparoscopic adrenalectomy: Initial experience from a tertiary care centre in India.

INTRODUCTION: Laparoscopic adrenalectomy (LA) is now considered the standard for treatment of surgically correctable adrenal disorders. Robotic adrenalectomy has been performed worldwide and has established itself as safe, feasible and effective approach. We hereby present the first study in robotic transperitoneal LA from Indian subcontinent.
MATERIALS AND METHODS: We conducted a retrospective evaluation of 25 patients who had undergone robotic assisted LA at a tertiary health centre by a single surgeon. Demographic, clinical, histopathological and perioperative outcome data were collected and analysed.
RESULTS: Mean age of the patients was 45 years (range: 27-65 years). Eleven male and 14 female patients were operated. Mean operative time was 139 min ± 30 min (range: 110-232 min) and mean blood loss was 85 ml ± 12 ml (range: 34-313 ml). Mean hospital stay was 2.5 ± 1.05 days (range: 2-6 days). Mean visual analogue scale score was 3.2 (range: 1-6) mean analgesic requirement was 50 mg diclofenac daily (range: 0-150 mg). Histopathological evaluation revealed 11 adenomas, eight phaeochromocytomas, two adrenocortical carcinomas, and four myelolipomas. According to Clavien-Dindo classification, three patients developed Grade I post-operative complications namely hypotension and pleural effusion.
CONCLUSION: Robotic adrenalectomy is safe, technically feasible and comfortable to the surgeon. It is easier to perform with a short learning curve.

INTRODUCTION

In recent times, laparoscopic adrenalectomy (LA) has been regarded as the preferred surgical approach for the treatment of most surgically correctable benign adrenal disorders and certain malignant tumours. LA has replaced the conventional open procedure and is accepted as the treatment of choice for patients with benign adrenal lesions.[1] Recently, robotic technology has been introduced into laparoscopic clinical practice. In 2001, Horgan and Vanuno reported on the first robotic adrenalectomy.[2] The robotic system offers certain advantages over traditional laparoscopic surgery such as three-dimensional optics, magnified view with excellent resolution and depth perception, 7° of freedom at wrists for operating instruments, filtering out tremors, and allowing precise movements. In addition, the surgeon has control of a steady camera, two operating robotic arms, and an optional fourth arm, which can be used as a retractor. Last but not the least; it enables the surgeon to operate in a comfortably seated position. These advantages could theoretically improve LA procedure and then lead to improved peri- and post-operative outcomes.

We hereby describe our initial experience of robot assisted LA at our institute including functional and oncological outcomes.

MATERIALS AND METHODS

We conducted a retrospective evaluation of patients who underwent adrenalectomy at our institute. In total, 25 robot assisted laparoscopic adrenalectomies were carried out in our department from February 2012 to April 2013 by a single surgeon. The operating surgeon had an adequate experience of open and laparoscopic adrenalectomies. Demographic, perioperative, pathologic, and oncological outcome data were collected and analysed. Visual analogue scale (VAS) was used to assess the pain in the postoperative period. Pain score was obtained once daily until the patients got discharged from the hospital before the administration of analgesics. 50 mg diclofenac was given to the patient if the VAS score was above 2. A surgeon fatigue index (SFI) was calculated according to the numerological rating scale. It is not a validated tool, but just a rough estimate of surgeon's fatigue. The operating surgeon was asked to rate the discomfort after completion of the surgery on a scale of 1-10. Five patients had undergone open adrenalectomy during this period. The reasons for performing open adrenalectomy were increased size (>10 cm), infiltrative tumours and financial issues. Patients with suspicion of phaeochromocytoma underwent the same pre-operative pharmacological management with alpha-blocker as in open surgery.

The surgical technique is essentially similar to laparoscopic surgery. The patient is placed in modified flank position with table break at the level of the 12th rib. The Da Vinci (DV) robot surgery system is docked over the ipsilateral shoulder. Initially, the table's position was changed according to the robot, but now we prefer to move around the robot according to the position of the patient as we observed faster docking with this technique. Pneumoperitoneum is made by veress needle at the lateral margin of rectus muscle two-finger breadth above umbilicus. We normally use only 30° down scope for dissection and two robotic arms for two instruments namely fenestrated bipolar forceps and the cautery hook. Four ports are used on either side with an additional fifth port used occasionally on the right side for retracting liver. The port position is as shown in Figures 1 and 2. The key steps involved in right adrenalectomy include division of the triangular ligament, division of gerotas fascia, early identification and division of adrenal vein at its junction with inferior vena cava, mobilisation of the adrenal gland posteriorly, laterally and from kidney inferiorly. The same techniques apply on left side also except for mobilisation of spleen and division of splenocolic ligament and identification of adrenal vein at its junction with renal vein. Meticulous care is taken to avoid manipulation of tumour, and periadrenal tissues are used for grasping the adrenal gland. According to the operating surgeon, use of robot is especially advantageous in dissecting and clipping adrenal vein with minimal manipulation of the adrenal gland.

Figure 1

Port placement on left side

Figure 2

Port placement on right side

RESULTS

The various demographic data and patient profile is shown in Table 1. Mean age of the patients was 45 years. Eleven patients were male, and 14 were female. Fifteen patients were operated for left side tumours, and ten had right side tumours. Two patients developed intra-operative hypertension that was controlled easily with intravenous nitoglycerine drip. There was no incidence of any arrhythmias intra-operatively or post-operatively. The mean console time was 139 min ± 30 min which was considerably lesser than reported for laparoscopic cases in the literature. Initially, the mean docking time for first 15 cases was roughly 35 min that got reduced to 22 min for next 10 cases. The mean intraoperative blood loss was 85 ml ± 12 ml. Only one adrenocortical cancer patient had significant bleeding that needed blood transfusion. The mean hospital stay was 2.5 ± 1.05 days. Patients were mostly pain-free during the hospital stay. Pain score was calculated daily until the patient was discharged from the hospital using numerical rating scale. Mean VAS score was 3.2 (range: 1-6). The daily analgesic requirement was approximately 50 mg of diclofenac. According to Clavien-Dindo classification, three patients developed Grade I post-operative complications namely hypotension and pleural effusion. No Grade 2 or higher complications were present. Hypotension occurred in the immediate post-operative period in patients harbouring phaeochromocytoma and was managed with intravenous fluids. Pleural effusion was mild and mostly reactive. It was observed in patients with upper polar tumours. There was no respiratory distress and effusion resolved on its own. There was no mortality. The mean SFI based on a numerological rating scale was found to be a low 2.4 (range: 1.5-6).

Table 1

Patient profile

We compared these patients with another cohort of patients who underwent LA over the last 5 years. Table 2 depicts a comparison between laparoscopic and robotic group in terms of demographic and operative parameters.

Table 2

Comparison of the patients undergoing laparoscopic and robotic adrenalectomy

DISCUSSION

In the last decade, LA has been established as standard of care for benign adrenal disease[13456] and increasingly considered for selected malignant lesions.[78910] First described in 1992,[11] LA has been shown to be well-tolerated, reduce patient morbidity, decrease costs, and shorten convalescence compared with open surgery.[45121314] However, surgeons need to confront some disadvantages during traditional laparoscopy, including an unstable operating field, orientation error due to camera holding and manipulation by the assistant, limitation of range and freedom of movement, inferior ergonomic design of the instruments, natural hand fatigue, tremors, and a two-dimensional operative field. Gill et al. first demonstrated the feasibility and effectiveness of adrenal surgery in a porcine model.[15] Subsequently Horgan and Vanuno[2] reported the first robotic adrenalectomy in humans. Since then more than 50 studies have been published on robotic adrenalectomy,[16171819202122232425] but only few studies had more than 20 patients.[161718192021] All in all, robotic surgery has proved to be a useful and significant advancement in performing adrenalectomies. It has proved to be equally efficacious if not superior to the LA. Newer modifications and advances have been made in robotic adrenalectomy such as retroperitoneal adrenalectomy and partial adrenalectomy. The disadvantages are lack of tactile feedback with robotic instruments, inability to reposition the patient once the robot is docked, and limited options for tissue coagulation devices such as the harmonic scalpel (non-wristed instrument). The lack of tactile feedback requires surgeons to rely on visual cues and experience to avoid tissue injury, which is not a trivial issue.

The conversion rate from robotic to open is reasonably low and comparable to LA. In one of the initial large series, Brunaud et al. reported a conversion rate of 7%.[19] Subsequent series also reported a low conversion rate in the range of 5-8%.[161821] The main reasons for conversion are difficult or aberrant anatomy, uncontrolled bleeding and large size of the tumour. We didn’t have any conversion perhaps because of stringent preoperative selection criteria. Brunaud et al.[16] have reported that patients who were converted to open adrenalectomy had a body mass index (BMI) Z29 kg/m2 (three out of four), tumour size >6 cm (two out of four), or pheochromocytoma (two out of four).

Studies on robotic adrenalectomy have all demonstrated reasonably low complication rates and morbidity. Morino et al. described two cases of severe intra-operative hypertension in their series of 10 patients.[22] The basic principles of surgery for phaeochromocytoma remain the same and apply as well in robotic surgery. The tumour should be minimally manipulated, and adrenal should be grasped by periadrenal tissues. Proper identification of planes and upward traction by bipolar forceps is equally important to avoid inadvertent manipulation. We also experienced two cases of intra-operative rise in blood pressure that were adequately controlled by intravenous nitroglycerine drip and fluid management. The pharmacological pre-operative preparation of phaeochromocytoma remains the same irrespective of the approach used.

Length of hospital stay has been shown to be equivalent between robotic and LA.[1619] It has mainly ranged from 2 to 6 days. The mean hospital stay in our series was also similar to that reported in the literature. Besides hospital stay, we observed that the patient had considerably lesser post-operative analgesic requirement as compared with open surgery.

In comparison to pure laparoscopic approach, robotic adrenalectomy has longer operative time. In 2006, the median operative time was reported to be 185 min by Winter et al. on a series of 30 RAs performed by 3 surgeons at a single institution.[17] In another study by Brunaud,[16] mean operative time decreased significantly (P = 0.03) from 101 min in the first 50 cases to 88 min for the last 45 cases (five conversions were excluded). Nordenstrom et al.[21] showed that the median skin-to-skin time for all 100 patients was 113 min (25 and 75 percentiles, 92-159 min), and 106 (range: 58-343) for the last 50 patients. The skin-to-skin time decreased significantly with the number of patients (P = 0.0001). The median console operation time for the whole series was 88 min (range: 39-397 min). In a recent study, Giulianotti et al.[20] showed that mean operative time was 118 min. Interestingly, the difference in operative times between the latest robot version (DVs system with four arms) and the previous one (DV system) was not significant (115 vs. 122 min; P = 0.65). Robotic adrenalectomy may though confer a time advantage for obese patients; Brunaud et al. in two papers[1619] noted positive correlation between patient's BMI (>30 kg/m2) and duration of LA, but no correlation in patients having the robotic procedure. In one study, larger tumour size (>55 mm) increased operative time for LA compared with robotic adrenalectomy, but this difference did not exist with smaller tumours. Other factors that might improve operative times for robotic adrenalectomy are side (right > left), experience of the side surgeon, and laparoscopic experience of the primary surgeon.[18] We observed that docking time and the overall time decreased with increasing experience of the operation theatre personnel and operating surgeon.

CONCLUSION

Robotic adrenalectomy is feasible, well-tolerated and produces the desirous result along with ease to the surgeon based on shorter operative time, lesser blood loss, and lesser pain score, lesser SFI and shorter hospital stay. This is the first series of robotic adrenalectomy from Indian subcontinent. Limitations of our study include a small number of patients, short follow-up and lack of cost analysis. The start-up costs, cost of maintenance of the robot, and cost of disposables that are used in each robotic case compared to similar laparoscopic procedures in addition to the marketing value of the robot are not evaluated in this study.