Cardiovascular Changes during Robot-Assisted Pelvic Surgery

Abstract

The application of robotic assistance in pelvic surgery has become popular across multiple specialties during the past decades, facilitating minimally invasive surgery. The most remarkable challenges regarding these procedures are the carbon dioxide pneumoperitoneum and steep Trendelenburg position. The combination of two factors affects the patient additionally or synergistically and have important physiological effects on cardiovascular system. All those changes are usually well tolerated in patients with normal cardiac function, but it can be different in elderly patients or even in patients with underlying heart conditions. In order to provide the proper management of patients undergone the robotic surgery, we aim to thoroughly understand these effects and overview the risks and possible related cardiovascular complications. Further, a short introduction on dangerous areas of robot-assisted pelvic surgery will be briefly reviewed.

1. Introduction

Prostate cancer remains the most common solid organ malignancy and the second leading cause of cancer death in the US men [1]. Radical prostatectomy is a standard treatment option for localized carcinoma of the prostate, that showed a significant relative risk reduction in cancer-specific mortality as compared with watchful waiting. Radical cystectomy and pelvic lymph node dissection are the standard treatment options for muscle-invasive bladder carcinoma, but this operation is a surgical procedure associated with the highest morbidity and mortality among all surgical operations. Laparoscopic cystectomy was introduced to decrease associated morbidity, and resulted in a significantly lower intra-operative blood loss and transfusion rates, lower pain scores, and allowing a more rapid resumption of oral intake and a shorter hospital stay. Uterine cancer is one of the few cancers with increasing incidence and mortality in the United States. It is the fourth most common cancer diagnosed and the seventh most common cause of cancer death among US women [2]. Hysterectomy is the second most commonly performed procedure in women of reproductive age, and nearly 600,000 hysterectomies are performed annually; about 20 million US women have had a hysterectomy [3]. In 2016, colorectal cancers accounted for 8.5% of all new malignant cancer cases and 8.7% of all cancer deaths in the US [4]. Laparoscopic approach has become the preferred standard of care in colorectal surgery and has been proven to be as safe and effective as open surgery, and associated with a lower blood loss and shorter length of stay.

The introduction of robot-assisted surgery, specifically the da Vinci Surgical System (Intuitive Surgical, Inc), is one of the biggest breakthroughs in past decades, and represents the most significant advancement in minimally invasive surgery. Initially used in urology, particularly in radical prostatectomy, the robotic technique became the most suitable for operations in a closed and restricted pelvic space across different specialties including colorectal and gynecologic surgery, making the indications for robot-assisted laparoscopic pelvic surgery (RALPS) widely increased. Robotic assistance allows a three-dimensional stable operator-controlled high-definition magnified view of the operative field, filtrating the tremor of the surgeon, and enabling precise movements of instruments with seven degrees of freedom, overtaken the limitations of standard open and/or laparoscopic surgery. Robot-assisted surgery represents an advantage in terms of smaller incisions, precise dissection in a confined space, reduction of intraoperative blood loss and lower transfusion rate, fewer postoperative pain and complications, decreased in-hospital death rate and length of stay, and faster return to daily functions. Age and obesity are significant risk factors for malignancy, yet complicate the surgery. RALPS is feasible and safe for patients with complicated diseases compared with conventional laparoscopic or open surgeries. Robotic procedures can reduce the cost of operation in elderly or morbidly obese patients with comorbidities, as these procedures generally require a shorter hospital stay than open methods. As the prevalence of obesity climbs steadily, the treatment of these patients with robotic surgery will increase. Multiple postoperative advantages of this technique permit safe management of patients with more and more severe cardiorespiratory disease.

As the previous surgical techniques, this one is not without limitations. First, potentially long duration of surgery (initial case series reported a longer mean operative time up to 270 minutes but this has since been reduced to a mean of 150 minutes). Second, RALPS requires a much Trendelenburg tilt of 30 to 45 degrees – steep Trendelenburg position (sTrP). This extreme position causes significant and potentially adverse cardiovascular alterations. The most remarkable challenge regarding RALPS is the carbon dioxide (CO₂) pneumoperitoneum (PP) resulting in ventilatory and respiratory changes. In compromised patients, cardiorespiratory disturbances aggravate the hypercapnia. Gasless laparoscopy may be helpful to reduce the pathophysiological changes induced by PP but increases technical difficulty. This becomes more complicated in operations where sTrP and PP are combined, increasing the risk of hemodynamic disorders.

2. Pathophysiological cardiovascular effects of steep Trendelenburg position and pneumoperitoneum during robot-assisted pelvic surgery

In RALPS, hemodynamic alterations are derived from the three origins: first is the intraabdominal pressure (IAP) created by the PP; second is the existence of an insufflation CO₂ that is absorbed by the blood; third is the sTrP of the patient. These factors account for the majority of physiological changes in the patient in addition to the events that develop from surgical intervention. The interactions of these factors are important in the intraoperative management of the RALPS patient. Standard IAP levels between 12 and 15 mm Hg cause increase in cardiac output by applying pressure to splanchnic venous bed and are useful for performing procedures in most cases [5]. On the other hand, higher insufflation pressure up to 20 mm Hg apply compression over inferior cava vena causing a preload reduction and a decrease in the cardiac output, but are safe and have no significant short-term effects on organ perfusion, and not associated with a higher complication rate [6]. Steep TrP is essential for the final hemodynamic result during RALPS; it increases the venous return and compensates blood loss. The combination of two factors the sTrP and PP can cause significant cardiovascular changes, and an increase in the angle of inclination can further exacerbate these changes [7]. PP with high IAP and sTrP may affect the excretion of CO₂. If pulmonary ventilation is not enough to eliminate the CO₂ absorbed from the PP, the dissolved CO₂ causes hypercapnia and acidosis. Hypercapnia and acidosis decrease the cardiac contractility, make myocardium more sensitive to catecholamines and cause peripheral vasodilatation. Sympathetic activation caused by hypercapnia finally leads to tachyarrhythmia and peripheral vasoconstriction [8]. Vagal (parasympathetic) stimulation may cause bradyarrhythmia in a range from bradycardia to asystole, and hypotension [9]. These effects may further complicate clinical management of patients with underlying chronic lung disease or the morbidly obese. Technical disadvantages of RALPS in patients with obesity include excessive fat tissue, deeper and narrowed true pelvis that result in limited working space, long distance to operative field, difficulty in trocars placement, and suboptimal visualization [10, 11].

Table 1 shows the results of different studies in which the intraoperative hemodynamics, cardiac function, filling volume and pressure, and cardiac variations were measured through the operation time relative to the values before the induction of anesthesia. Studies reporting mean arterial pressure (MAP) changes have not been consistent. In a majority of studies, an increased or unaffected MAP was demonstrated. In the most of studies there were no changes in heart rate (HR), whereas one study showed an increase, and the remaining studies showed decreased HR. In general, the stroke volume (SV), cardiac output (CO), and cardiac index (CI) remained stable, except one study, in which cardiac function significantly decreased, authors explained by the combined effect of general anesthesia and PP. All the reported studies described an increased or unchanged systemic vascular resistance (SVR). SVR also increased in studies in which no decrease in CO was reported. Whereas the normal heart tolerates increases in afterload under physiologic conditions, the changes in afterload produced by the PP can result in deleterious effects in patients with cardiac diseases and may lead to further decrease in CO. Significant 80% [34] up to 200% [43] increasing in Central venous pressure (CVP) as well as pulmonary mean artery pressure (PMAP) and pulmonary artery wedge pressure (PAWP) after the institution of PP and sTrP was seen in all of studies.

Function	Status
	Increased	Decreased	Unchanged
Hemodynamics
Mean arterial pressure	[7, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]	[26, 27, 28, 29, 30, 31, 32, 33]	[34, 35, 36, 37, 38, 39, 40, 41, 42]
Heart rate	[25]	[14, 23, 26, 27, 29, 30, 31, 33, 36]	[7, 12, 13, 15, 16, 17, 18, 19, 20, 21, 22, 24, 28, 34, 35, 38, 39, 40, 42]
Cardiac function
Stroke volume	[32]	[27]	[19, 22, 24, 38]
Cardiac output	—	[26, 27]	[17, 19, 20, 22, 24, 38, 41]
Cardiac index	—	[27]	[15, 16, 18, 24, 25, 29, 34]
Ventricular end-diastolic area / stroke work index / ejection fraction	[20, 22]	[24]	—
Systemic vascular resistance	[19]	—	[22, 25, 29, 34, 38]
Filling volume / pressure
Aortic diameter	[19]	—	—
Central venous pressure	[12, 15, 16, 18, 20, 21, 22, 23, 25, 27, 34, 35, 37, 38, 40]	—	—
Pulmonary mean artery pressure	[15, 22]	—	—
Pulmonary artery wedge pressure	[15, 22]	—	—
Cardiac variations
Heart rate^a	[36]	—	—
QTc interval^b	[28]	—	—
Tp-e interval^c	—	—	[28]
Pulse pressure	[14]	—	—
Stroke volume	[14]		[20]

Table 1.

Summary of literature search, including changes in intraoperative hemodynamics, cardiac function, filling volume and pressure, and cardiac variations during RALPS.

^a

Computerized ECG.

^b

HR-corrected QT (QTc) interval.

^c

Tpeak–Tend (Tp-e) interval.

2.1 Safe effects of steep Trendelenburg position and pneumoperitoneum on central hemodynamics

Pneumoperitoneum resulted in an increased MAP, decreased SV, and increased pulse pressure variation (PPV) and stroke volume variation (SVV) compared with the supine position. Pneumoperitoneum combined with sTrP resulted in an unchanged MAP, increased SV, unchanged PPV, and increased SVV compared with isolated PP in patients without cardiopulmonary disease. The PP induced increases in abdominal pressure may compress the inferior vena cava, resulting in decreased right ventricular preload [14].

The effects of extraperitoneal and transperitoneal CO₂ insufflation on hemodynamic parameters were assessed in [17]. HR did not change significantly during either of the surgical approaches. Although MAP and CO did increase significantly during transperitoneal insufflation, although not during extraperitoneal insufflation, the differences between the methods were not statistically significant.

Despite a 50–100% increasing in CVP, PMAP and PAWP, the sTrP and PP did not change the CI and contractility of the right ventricle [15].

Cerebral blood flow-carbon dioxide reactivities in the supine and modest TrP under PP were compared in [16]. The main result is that there is no change between the supine position and the 30° TrP.

Combination of the 45° sTrP and insufflation pressures of 20 mm Hg resulted in a MAP reduced by 17%, HR reduced by 21%, and CO reduced by 37%. Overall, patients tolerated the procedure well with minimal clinically significant cardiopulmonary effects. For patients with limited cardiopulmonary reserve, however, physicians must weight these benefits with the negative cardiovascular changes associated with this type of procedure [26].

Steep TrP and high-pressure PP leads to significant decrease in SV and CO. Although hemodynamic parameters decreased compared to the baseline, they were within the physiological normal limits and all these parameters returned to baseline after deflation of PP in the supine position [27].

The effects of volatile anesthetic sevoflurane and intravenous propofol on Central hemodynamics were compared in [18]. No intergroup differences in MAP, CI, and CVP being at any time point in PP and sTrP, even though HR was lower in sevoflurane group. Compared with time point before surgery, MAP and CVP were significantly higher in both groups. There were no differences within each group for CI at each time point. There were no major complications on normal postoperative rounds in either group.

Steep TrP significantly increased the SV, whereas PP decreased the aortic diameter, and the combination of sTrP and PP significantly increased MAP and CVP, but did not change CO and SV [19].

Improved hemodynamics with significant increase of MAP, CVP and CO under combination sTrP with PP were observed in [20]. All the variables studied remained within the clinically acceptable range and did not deteriorate left or right ventricular function.

Central venous pressure increased after the institution of PP and sTrP and returned to baseline range following reinstitution of supine position after completion of robotic pelvic surgeries. These findings can be explained by combination of increased intra-abdominal, intrathoracic pressures and acute volume loading during PP and sTrP [35].

Although the sTrP combined with a PP significantly influenced cardiovascular homeostasis, all investigated variables remained within a clinically acceptable range, and a combination of the prolonged sTrP and PP was well tolerated by patients. During institution of the sTrP, MAP and CVP increased significantly. The observed increase in pressure is the result of increased hydrostatic pressure at the external auditory meatus caused by the tilting of the table. Because MAP increased by a greater absolute amount than CVP (34 vs. 23 mm Hg, respectively), at least part of the increase in MAP must also be caused by increased CO, SVR, or both [21].

The influence of sTrP on cerebral hemodynamic homeostasis was elucidated in [37]. While patients were in the sTrP, zero flow pressure (ZFP) increased in parallel with CVP. The pulsatility and resistance indexes, and ZFP – CVP gradient did not increase significantly after 3 h of the sTrP. Albeit the unphysiological sTrP combined with the need for PP raises major concerns for the physiological homeostasis of the patient, especially for intracranial pressure and brain perfusion, it does not compromise cerebral perfusion and seems to be well tolerated by most patients.

RALPS performed with low pressure (8 mm Hg) PP and sTrP was associated with significant variations in arterial pressure, CVP, SVR, left ventricular end-diastolic and end-systolic volume, and ejection fraction. With the return to neutral position at the end of surgery, with PP deflation, most of the assessed parameters returned to baseline value, with the exception of SVR and CO. However, all variables remained within limits safely manageable by the anaesthesiologists [38].

Two- to three-fold increases of right- as well as left-sided filling pressures during PP with sTrP was found in [22]. The index of left ventricular filling was at a level seen during heart failure. Pulmonary hypertension, with systolic pulmonary artery pressure exceeding 35 mm Hg, was recorded in 75% of the patients. Furthermore, right-sided and left-sided filling pressures were almost equal. Systemic blood pressure was also increased, but there was no change in CO.

Hemodynamic changes, such as a significant decrease in HR after induction of anesthesia, the insufflation of PP and the transfer patient to sTrP were found in [29]. In the time of operation, the significant decrease of MAP was also observed. Although these hemodynamic parameters were reduced compared to the baseline level, they were within the physiological norm and all indicators returned to the baseline level after the elimination of PP. There were no cases of cardiovascular complications in the early postoperative period.

Low-pressure PP, sTrP and mechanical ventilation may interact and be the origin of the alterations in the autonomic nervous system modulation of HR variability. Minor alterations in cerebral oxygenation and autonomic perturbations do not cause clinically significant alterations in a patient’s HR variability. This finding supports the safety of RALPS [36].

The impact of overweight on hemodynamic in patients undergoing RALPS with PP was investigated in [40]. The creation of prolonged PP had no adverse effects on hemodynamic parameters and no clinically relevant cardiovascular change was noted.

Cardiac output was not affected either by the sTrP nor establishment of a PP. Head-down position and prolonged PP were associated with an early elevation in CVP that was sustained and did not vary. A temporary increase of MAP was recorded. After the release of the PP, hemodynamic parameters returned to baseline levels except HR and CI [34].

Changes in circulatory status by measuring hemodynamic and cardiac function brought about by 28° TrP and establishment of the PP were examined in [24]. They found that head-down tilt and PP significantly decreased left ventricular ejection fraction but that left ventricular end-diastolic volume and CI did not change. These findings indicate that a sTrP and PP did not greatly influence cardiac function.

The clinical effects of general anesthesia with inhalational sevoflurane and total intravenous anesthesia with propofol were compared. Mean arterial pressure decreased in period of anesthesia induction and patient preparation and increased with sTrP and PP. Heart rate significantly decreased during the operation in both groups after sTrP and PP were established. All values were in physiologic ranges in all times [31].

Even with a standard 11–14 mm Hg PP, some form of mesenteric-splanchnic injury might be induced due to an extra gravitational pressure or a traction force caused by the exclusive fixed 45° TrP in addition to the duration of RALPS about 3.5 hours, but not any significant mesenteric-splanchnic ischemia was demonstrated [41].

Unchanged preload conditions, a slightly reduced contractility, and an 8% increase in HR, together with a 32% increase in SVR, combine to cause an 8% decrease in CO during pronounced PP, but generally normalized afterload and myocardial oxygen demand [25].

Brain regional oxygen saturation increased after the PP and further increased temporarily after the sTrP, and decreased afterwards. These changes were along with the alteration of MAP, but did not correlate with the changes of HR, indicating that MAP is the critical factor in the cerebral oxygenation. Anyway, PP and the sTrP in RALRP did not aggravate cerebral oxygenation [30].

Lower limb perfusion significantly increased after induction of anesthesia, establishment of PP, placing in TrP, when compared to the baseline in patients without previous episodes of peripheral vascular disease and morbid obesity. Arterial pressure decreased after induction of anesthesia and continued to show a decreasing trend throughout the operation. Cardiac index increased after TrP. These changes in cardiovascular physiology had negative effects on systemic perfusion, but in general, sTrP and general anesthesia improve microcirculation [32].

2.2 Negative effects of steep Trendelenburg position and pneumoperitoneum on central hemodynamics

Steep TrP is a challenging clinical setting to anesthetists due to the risks of position and long duration of PP. The creation of PP and sTrP increased MAP, that can be explained by the increase of hydrostatic pressure caused by the tilting of the table, also is caused by increased CO and SVR. PP and head-down position caused acute volume loading which causes acute elevation of CVP. Over subsequent hours, the MAP and CVP remained stable, then decreased significantly after reassuming the supine position, but remained within acceptable ranges [12].

Pneumoperitoneum and TrP caused an increase in MAP and middle ear pressure. Although the magnitude of this increase was within the normal range and none of patients suffered from ear problems postoperatively, this propensity for increase may cause problems in patients with preexisting disease [13].

The degree of head-down angle affects the cardiovascular parameters. MAP was increased significantly with PP, and showed a much greater increase (up to 31% compared with baseline) in the first 5 min after placing in the sTrP [7].

The effect of dexmedetomidine on QTc was evaluated in [28]. None of the patients had a QTc interval of >450 msec before surgery, but sTrP and PP resulted in a significant lengthening of the QTc interval > 450 msec in 2 patients and > 20 msec prolongation from baseline in 22 patients (96%). The overall result was that sTrP and PP can increase the risk of torsade de pointes for patients susceptible to ventricular arrhythmias, even when preoperative ECG findings are normal [28].

High prolonged PP and sTrP can produce adverse cardiovascular effects, and the results of study [23] demonstrated that MAP remained unchanged, but HR decreased significantly and required intervention. The CVP values were also above the normal limits. These high values might be due to the sTrP as they returned to their initial values by the end of the operation. Although the most obvious effects on HR, MAP, and CVP occurred immediately after the patients were moved into the sTrP with PP, these measurements continued to be affected to a lesser degree until the supine positioning at the end of the procedures. The most obvious changes were observed in the CVP.

Autonomic nervous system regulations following sTrP were investigated via evaluating HR variability [44]. A statistically significant decrease in the values of low-frequency and high-frequency spectral bands, representing sympathetic and parasympathetic activity, respectively, correlated with 20% decrease in HR, and in other hemodynamic parameters from the start until the end of the operation.

Significant increase in concentration of malondialdehyde regarded to be the most reliable and producible markers of oxidative stress in the clinical setting, and decrease in gastric intramucosal pH value after the induction of PP was observed in [39]. After PP deflation, these values increased steadily and reached a peak 30 minutes after deflation, which was significantly higher than that during PP insufflation. Consistent with these findings, a prolonged PP could lead to decreased splanchnic blood flow and increased oxidative stress, not only during the PP but also after the deflation.

Hemodynamic changes during RALPS reveal autonomic response to the challenges (i.e., general anesthesia and head down position), and non-neurally mediated increase of systolic arterial pressure caused by PP. Association between the vagal stimulation due to sTrP and sympathetic withdrawal caused by general anesthesia could lead to severe bradycardia and cardiac arrest in risky patients [45].

Cerebrovascular autoregulation slowly impaired over a long time period in sTrP combined with PP. High MAP might trigger or aggravate the formation of cerebral edema. To avoid neurological deterioration in patients placed in an sTrP for more than 3 h, it may be beneficial to maintain the MAP within the normal range and to minimize the duration of sTrP as much as possible [42].

The concomitant pathology, cardiac depressants, age, the duration of surgical intervention and anesthesia are of great importance to observed unfavorable changes in a cardiovascular system. The higher intra-abdominal pressure and the clearly expressed TrP create a prerequisite for more frequent hemodynamic changes, concealing a risk for the life of sick persons [33].

3. Cardiovascular complications occurring the robot-assisted laparoscopic pelvic surgery

Steep TrP and PP are required to allow adequate surgery exposure in robotic pelvic procedures. The risk of perioperative cardiovascular complications is increased by a long-time in the proper patient positioning. In contrast with respiratory complications, hemodynamic complications do not increase with surgery duration. Positioning-related complications are even more common in obese patients related to weight pressure and longer operative time. Peritoneal insufflation can result in hypotension, arrhythmias (bradycardia) or even cardiac arrest (asystole) due to vagal response, especially in patients with cardiovascular disease. We found very few cardiovascular complications in four case reports [46, 47, 48, 49], two review articles [50, 51], five prospective [12, 20, 23, 52, 53], and ten retrospective [54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64] analyses, shown in Table 2.

Cardiac events	Procedure characteristic	Patient’s demographics: number (n); ASA functional class; age; BMI	Number of patients (rate) with events
Arrhythmias (atrial fibrillation / bradycardia)	[12, 23, 50, 61, 63]	n = 874; ASA I-IV; 26 to 84 years; 16 to 44 kg/m^2	20 (2.3%)
Myocardial ischemia / infarction	[54, 56, 57, 59, 63]	n = 2717; ASA I-IV; 44 to 78 years; 19 to 38 kg/m^2	11 (0.4%)
Cardiac arrest	[54]	n = 1241; ASA I-IV; 46 to 74 years; overweight and obese 69.6%	4 (0.3%)
Other cardiac complications (mitral insufficiency, pulmonary edema)	[20, 52]	n = 14; ASA II-III; 24 to 61 years; 19 to 38 kg/m^2	2 (14%)
Cardiac complications not detailed (including myocardial infarction, arrhythmia, heart failure, shock)	[51, 53, 55, 58, 60, 62, 64]	n = 57220; 32 to 90 years; 17 to 70 kg/m^2	465 (0.8%)

Table 2.

Types and rates of cardiovascular complications.

Myocardial infarction was a result of intraoperative drug-eluting stent thrombosis after a patient developed a new left bundle branch block and was ultimately taken to the cardiac catheterization lab [47]. A patient with significant cardiac risk factors underwent a RALPS with cardiac arrest and was subsequently successfully resuscitated [46]. Another fatal myocardial infarction was in a 52-year-old patient with ASA physical status IV [48]. In a case of 72-year-old man, after 22° PP creation, severe bradycardia and complete atrioventricular block were observed, which is considered to be attributed to a vagal reflex; thus, the surgery was extended by inserting a temporary pacemaker [49].

Analyses of a large database demonstrated 0.9% cardiac complications after RALPS. Higher prevalence of cardiovascular-related comorbidities in morbidly obese patients may be involved in the increased incidence of cardiac complications [64]. In a largest sample study evaluated and compared incidence of perioperative complications among of non-obese, obese, and morbidly obese patients undergoing RALRP, the rates of intraoperative complications were similar [60].

4. Perioperative monitoring during robot-assisted laparoscopic pelvic surgery

RALPS is performed while the patient is under general anesthesia with endotracheal intubation. For most procedures, the standard American Society of Anesthesiologists monitoring is sufficient. These includes noninvasive blood pressure, electrocardiogram, pulse oximetry, capnography, temperature monitoring, bispectral index, and urine output. Because of relatively short operative times and minimal blood loss, invasive monitoring is rarely indicated. One freely flowing peripheral IV and plethysmography offer necessary access and hemodynamic information. In [65] noninvasive continuous arterial blood pressure measurements using the ClearSight system (BMEYE, Amsterdam, The Netherlands) were not comparable to those obtained invasively in patients undergoing RALPS because of the device tended to overestimate blood pressure. For hemodynamic optimization, stroke volume estimation and its response to fluid infusion is recommend. There is no justification for CVP nor pulmonary artery catheter monitoring based on hemodynamic changes related to PP alone.

Additional monitoring should be considered to account for patient co-morbidities, the risk of intraoperative bleeding, or longer operative times. Hemodynamically unstable or patients with cardiovascular disease intra-arterial blood pressure may be monitored by arterial cannulation [25]. The most popular additional cardiovascular monitoring for older patients with cardiopulmonary comorbidities includes:

• Invasive arterial blood pressure with cardiac output monitoring: FloTrac/Vigileo™ (Edwards Lifesciences LLC, Irvine, CA, USA) [16, 18, 27, 32]

• Transesophageal echocardiography: Haemosonic-100 (Arrow International; Everett, MA, USA); Vivid i™ (General Electrics); iE33® X7-2t (Philips N.V., Amsterdam, Netherlands); TE-V5M (Acuson Sequoia C512 Ultrasound system; Siemens, Malvern, PA) alone [19, 26] or with FloTrac/Vigileo™ [14, 20, 24, 38]

• Transpulmonary arterial thermodilution: Swan-Ganz CCO combo (CCO/SvO₂ Edwards Lifesciences LLC, Irvine, CA, USA); PiCCO Plus (Pulsion Medical Systems, Munich, Germany); Draeger Infinity Delta PiCCO SmartPod (Draeger Medical Systems, Inc., Telford, PA, USA) [15, 22, 25, 34]

As sum, Joint Consensus on Anesthesia in Urologic and Gynecologic Robotic Surgery (JC-STARS group) recommend tailored hemodynamic monitoring of the patient based on the perioperative risk [66].

5. Conclusions

Robot-assisted pelvic surgery with the da Vinci surgical system is increasingly being applied. Despite the increasing popularity, there is no unequivocal evidence to show the superiority of robotic surgery over traditional laparoscopic surgery in terms of cardiovascular complications. Interpreting the effects of the steep Trendelenburg position and that of CO₂ pneumoperitoneum separately is impossible; the combination of the factors affects the patient additionally or synergistically and have important physiological effects on cardiovascular system. All those changes are usually well tolerated in patients with normal cardiac function, but it can be different in elderly patients with ASA II-III risk or even in patients with underlying heart conditions. Cardiovascular complications not appear to be unique to RALPS and had no greater incidence. The intraoperative management of the RALPS patient presents manageable challenges. Patients should be properly monitored to understand the current situation, to maintain stability and to avoid the complications with the necessary interventions on time.