Carbon dioxide homeostasis during transperitoneal or extraperitoneal laparoscopic pelvic lymphadenectomy: a real-time intraoperative comparison

Single-Port Robot-Assisted Radical Prostatectomy: Where Do We Stand?

In 2018, the da Vinci Single Port (SP) robotic system was approved by the US Food and Drug Administration for urologic procedures. Available studies for the application of SP to prostate cancer surgery are limited. The aim of our study is to summarize the current evidence on the techniques and outcomes of SP robot-assisted radical prostatectomy (SP-RARLP) procedures. A narrative review of the literature was performed in January 2023. Preliminary results suggest that SP-RALP is safe and feasible, and it can offer comparable outcomes to the standard multiport RALP. Extraperitoneal and transvesical SP-RALP appear to be the two most promising approaches, as they offer decreased invasiveness, potentially shorter length of stay, and better pain control. Long-term, high-quality data are missing and further validation with prospective studies across different sites is required.

Anesthesiologic effects of transperitoneal versus extraperitoneal approach during robot-assisted radical prostatectomy: results of a prospective randomized study

Objectives:

To compare the effects of CO₂ insufflation on hemodynamics and oxygen levels and on acid-base level during Robot-Assisted Radical Prostatectomy (RARP) with transperitoneal (TP) versus extra-peritoneal (EP) accesses.

Materials and Methods:

Sixty-two patients were randomly assigned to TP (32) and EP (30) to RARP. Pre-operation data were collected for all patients. Hemodynamic, respiratory and blood acid-base parameters were measured at the moment of induction of anesthesia (T0), after starting CO₂ insuffation (T1), and at 60 (T2) and 120 minutes (T3) after insufflation. In all cases, the abdominal pressure was set at 15 mmHg. Complications were reported according to the Clavien-Dindo classification. Student's two–t-test, with a significance level set at p<0.05, was used to compare categorical values between groups. The Mann-Whitney U-test was used to compare the median values of two nonparametric continuous variables.

Results:

The demographic characteristics of the patients in both groups were statistically comparable. Analysis of intra-operative anesthesiologic parameters showed that partial CO₂ pressure during EP was significantly higher than during TP, with a consequent decrease in arterial pH. Other parameters analysed were similar in the two groups. Postoperative complications were comparable between groups. The most important limitations of this study were the small size of the patient groups and the impossibility of maintaining standard abdominal pressure throughout the operational phases, despite attempts to regulate it.

Conclusions:

This prospective randomized study demonstrates that, from the anesthesiologic viewpoint, during RARP the TP approach is preferable to EP, because of lower CO₂ reabsorption and risk of acidosis.

Intraperitoneal effects of extraperitoneal laparoscopic radical prostatectomy

OBJECTIVES

To compare routine radiologic and laboratory findings after extraperitoneal and transperitoneal laparoscopic radical prostatectomy (eLRP, tLRP) and assess relevant clinical correlations.

METHODS

Fifty consecutive eLRP and tLRP (laparoscopic and robot-assisted) were evaluated. Preoperative complete metabolic panel and complete blood count were determined, and these serum tests and amylase and lipase level measurements were repeated postoperatively. Ten consecutive eLRP and tLRP patients also underwent flat and upright abdominal x-rays. Operative time, perioperative complications, length of hospital stay, and amount of narcotic used were measured for each group.

RESULTS

On postoperative day 1, all eLRP patients evaluated (100%) had radiographic free air in the abdomen, as did 80% of the tLRP patients. Only 1 of 50 patients (2%) had elevated aspartate aminotransferase (eLRP), 2 of 50 (4%) had elevated alanine aminotransferase (both eLRP), and 4 of 50 (8%) had elevated amylase (3 eLRP, 1 tLRP). Postoperative narcotic usage (eLRP 25 +/- 3 mg versus tLRP 23 +/- 5 mg morphine equivalents) and operative times (eLRP 3.6 +/- 0.1 hours versus tLRP 3.8 +/- 0.1 hours) were similar between the groups. Length of hospital stay was lower in the eLRP compared with the tLRP group (1.9 +/- 0.1 days versus 2.2 +/- 0.1 days, P <0.05). Perioperative complications did not differ significantly between groups.

CONCLUSIONS

Extraperitoneal LRP and tLRP patients had comparable perioperative outcomes, and few had abnormal serum metabolic laboratory values postoperatively. Unexpectedly, abdominal free air was found in all eLRP patients evaluated radiographically on postoperative day 1, a finding that should be interpreted as normal and not specific for bowel injury in this context.

Laparoscopic radical prostatectomy: transperitoneal versus retroperitoneal approach: is there an advantage for the patient?

PURPOSE OF REVIEW

Radical prostatectomy is the standard treatment for localized prostate cancer; its translation to a laparoscopic approach is considered today not only as feasible and reproducible but also as a valid and teachable alternative to its open counterpart. Beyond the "classical" transperitoneal antegrade route codified by the Montsouris group, several extraperitoneal approaches were developed, claiming clinical equivalence and reduced risks of morbidity and operative times. This article summarizes various aspects of different approaches and their outcome.

RECENT FINDINGS

Complications reported about transperitoneal procedures definitely further the discovery or learning curves of the pioneering teams; the groups who developed extraperitoneal alternatives established their "new approaches" on a solid base of technical skills, acquired transperitoneally. Beyond the unsurpassed qualities of visual and working spaces belonging to the transperitoneal route, which should be taken into account with respect to teaching, transperitoneal antegrade approach to the prostate enables the surgeon with early hemostatic control and essential tactical choices to achieve negative surgical margins.

SUMMARY

So far, as oncological and functional results of both approaches seem equivalent, both approaches should be further developed and remain available for teaching purposes. The true benefit for patients lies more in global quality control of surgery than in an obsessional search for alternatives to established techniques that have already stood the proof of time.

Carbon dioxide elimination during laparoscopy in children is age dependent

The absorption of carbon dioxide (CO2) used for positive pressure pneumoperitoneum may lead to an increased CO2 load. CO2 elimination during laparoscopy has not been investigated previously in paediatrics. The aim of this study was to characterise the pattern of CO2 elimination during laparoscopic surgery in infants and children.

METHODS

Twenty children undergoing laparoscopy and 19 children undergoing laparotomy for elective abdominal operations were studied. Pneumoperitoneum was achieved using insufflation of unheated CO2. CO2 elimination (metabolically produced + absorbed; milliliters per kilogram per minute) was measured minute by minute during the operation by indirect calorimetry. End-tidal CO2 (kPa) was recorded every 10 minutes. The above variables were assessed before CO2 insufflation, during pneumoperitoneum, and after desufflation.

RESULTS

Before insufflation, CO2 elimination was 4.6 +/- 0.3 ml/kg/min and increased after 15 minutes of pneumoperitoneum to 5.2 +/- 0.3 (P <.001). Post desufflation, CO2 elimination decreased toward preinsufflation values, but did not return to baseline by the end of operation (5.8 +/- 0.3; P <.001). End-tidal CO2 was 4.7 +/- 0.2 preinsufflation, peaked at 1 hour (5.3 +/- 0.2; P <.001) and subsequently decreased in response to ventilatory adjustments. The total amount of CO2 insufflated was positively correlated with patient age (r2 = 0.27; P <.01). CO2 elimination was age related, as indicated by multilevel model analysis and by negative correlations between maximum increase in CO2 elimination and both age (r2 = 0.27; P <.01) and weight (r2 = 0.29; P <.01). These data suggest that the younger or smaller the child, the larger the increase in CO2 elimination. Seven patients (35%) responded to desufflation with a sharp transient increase in CO2 elimination, which did not appear to be related to patient age, length of pneumoperitoneum, abdominal pressure, or type of operation.

CONCLUSIONS

During pneumoperitoneum, younger children absorb proportionately more CO2 than older individuals. The short-lived increase in CO2 elimination postdesufflation may be related to an increase in venous return from the lower limbs after release of the abdominal pressure. These findings suggest that small children warrant close monitoring during laparoscopy and during the immediate postoperative period.

Arterial blood gases in extraperitoneal laparoscopic urethrocystopexy

BACKGROUND

The aim of this study was to investigate the effects of extraperitoneal laparoscopy and carbon dioxide insufflation on hemodynamic parameters, arterial blood gases and complications in urethrocystopexy operations.

METHODS

Twenty-five female patients who underwent extraperitoneal laparoscopic mesh urethrocystopexy operation for the correction of urinary incontinence were allocated to the study. Hemodynamic parameters were noted and blood gas analyzes were performed before the induction of anesthesia, 10 min after induction, 5 and 10 min after the beginning of carbon dioxide insufflation, at the end of carbon dioxide insufflation and 30 min after exsufflation.

RESULTS

There was no significant change in mean arterial pressure, peripheral oxygen saturation, arterial carbon dioxide pressure, and arterial oxygen saturation compared to preinsufflation and preinduction values. End-tidal carbon dioxide pressure did not increase above 45 mm/Hg during carbon dioxide insufflation. Arterial oxygen saturation and partial oxygen pressure did not decrease. Subcutaneous emphysema, pneumothorax, pneumomediastinum and pleural effusion were not noted in any patient.

CONCLUSION

We conclude that, extraperitoneal laparoscopic urethrocystopexy is not associated with hemodynamic and respiratory impairment.

Renal physiology. Laparoscopic considerations

Oliguria is a recognized component of the physiologic effect of increased intra-abdominal or retroperitoneal pressure. The cause is multifactorial, emanating from vascular and parenchymal compression, and is associated with systemic hormonal effects. Ureteral obstruction does not play a significant role. These changes are pressure-dependent and are usually not apparent until pressures reach 15 mm Hg or more. This effect is not associated with any histologic pathology or evidence of renal tubular damage. After the release of the pneumoperitoneum or pneumoretroperitoneum, the renal function and urine output return to normal with no long-term sequelae, even in patients with pre-existing renal disease. The entire operative team must understand the physiologic effects of CO2 insufflation, which allows appropriate intraoperative monitoring and management and minimizes intraoperative and postoperative complications.

Carbon dioxide absorption during extraperitoneal and transperitoneal endoscopic hernioplasty

Transabdominal preperitoneal (TAPP) or total extraperitoneal (TEP) hernioplasty are probably associated with differing degrees of CO(2) absorption which can influence anesthetic management and perioperative morbidity. We studied 20 patients with either TAPP or TEP for perioperative CO(2) absorption (calculated from CO(2) elimination and metabolic CO(2) production) and ventilatory changes required to maintain normocapnia (blood gas analyses). CO(2) absorption reached plateau values in the TAPP group, but increased over time in the TEP group. Median CO(2) absorption during insufflation was 61 mL/min (range 43-78) for TAPP and 114 mL/min (range 75-178) for TEP, with a maximum of 114 mL/min (range 75-178) for TAPP and 258 mL/min (range 112-585) for TEP. Median minute ventilation (V(E)) required for maintaining normocapnia was 9. 5 L/min (range 7.7-11.5) for TAPP and 12.9 L/min (range 9.0-22.6) for TEP (P: < 0.01). Seven patients in the TEP group required over 18 L/min V(E), although no patient in the TAPP group required more than 14 L/min V(E). All patients in the TEP group had significant subcutaneous emphysema resulting in one case of delayed tracheal extubation. We conclude that CO(2) absorption is consistently less with TAPP.

IMPLICATIONS

The greater magnitude of carbon dioxide absorption during total extraperitoneal hernioplasty puts an additional load on the lungs and could pose a risk for patients with chronic lung disease who might be unable to eliminate excess carbon dioxide.

Carbon dioxide absorption during extraperitoneal and transperitoneal endoscopic hernioplasty

Transabdominal preperitoneal (TAPP) or total extraperitoneal (TEP) hernioplasty are probably associated with differing degrees of CO(2) absorption which can influence anesthetic management and perioperative morbidity. We studied 20 patients with either TAPP or TEP for perioperative CO(2) absorption (calculated from CO(2) elimination and metabolic CO(2) production) and ventilatory changes required to maintain normocapnia (blood gas analyses). CO(2) absorption reached plateau values in the TAPP group, but increased over time in the TEP group. Median CO(2) absorption during insufflation was 61 mL/min (range 43-78) for TAPP and 114 mL/min (range 75-178) for TEP, with a maximum of 114 mL/min (range 75-178) for TAPP and 258 mL/min (range 112-585) for TEP. Median minute ventilation (V(E)) required for maintaining normocapnia was 9. 5 L/min (range 7.7-11.5) for TAPP and 12.9 L/min (range 9.0-22.6) for TEP (P: < 0.01). Seven patients in the TEP group required over 18 L/min V(E), although no patient in the TAPP group required more than 14 L/min V(E). All patients in the TEP group had significant subcutaneous emphysema resulting in one case of delayed tracheal extubation. We conclude that CO(2) absorption is consistently less with TAPP.

IMPLICATIONS

The greater magnitude of carbon dioxide absorption during total extraperitoneal hernioplasty puts an additional load on the lungs and could pose a risk for patients with chronic lung disease who might be unable to eliminate excess carbon dioxide.