Obesity is associated with decreased lung compliance and hypercapnia during robotic assisted surgery

Clinical Considerations and Outcomes of Robotic Urologic Surgery in Obese Patients

Obesity is associated with many significant physiological changes. These considerations are important to surgery, especially in urological procedures. Obese patients often undergo surgical procedures and are at higher risk of complications. This investigation reviews physiological and anaesthesia considerations for obese and morbidly obese patients. In addition, urological surgeries and procedures should be considered for these higher risk patients. Clinical anaesthesiologists must use detailed assessment and, when appropriate, consultation in developing safe anaesthesia plans for these patients. Newer technologies have improved safety related to airway management, advanced airway devices, and regional anaesthesia with ultrasound-guided nerve blocks, which can reduce the need for opioids postoperatively. Recent developments in drug and monitoring technologies have also been developed and can be effective for obese and morbidly obese patients undergoing urological procedures and perioperative surgery, thus improving the likelihood of safety in this higher risk population.

The Effect of Recruitment Maneuver on Static Lung Compliance in Patients Undergoing General Anesthesia for Laparoscopic Cholecystectomy: A Single-Centre Prospective Clinical Intervention Study

Background and Objectives: The aim of this study was to examine whether the use of an alveolar recruitment maneuver (RM) leads to a significant increase in static lung compliance (Cstat) and an improvement in gas exchange in patients undergoing laparoscopic cholecystectomy. Material and Methods: A clinical prospective intervention study was conducted. Patients were divided into two groups according to their body mass index (BMI): normal-weight (group I) and pre-obese and obese grade I (group II). Lung mechanics were monitored (Cstat, dynamic compliance-Cdin, peak pressure-Ppeak, plateau pressure-Pplat, driving pressure-DP) alongside gas exchange, and hemodynamic changes (heart rate-HR, mean arterial pressure-MAP) at six time points: T1 (induction of anesthesia), T2 (formation of pneumoperitoneum), T3 (RM with a PEEP of 5 cm H2O), T4 (RM with a PEEP of 7 cm H2O), T5 (desufflation), and T6 (RM at the end). The RM was performed by increasing the peak pressure by +5 cm of H2O at an equal inspiration-to-expiration ratio (I/E = 1:1) and applying a PEEP of 5 and 7 cm of H2O. Results: Out of 96 patients, 33 belonged to group I and 63 to group II. An increase in Cstat values occurred after all three RMs. At each time point, the Cstat value was measured higher in group I than in group II. A higher increase in Cstat was observed in group II after the second and third RM. Cstat values were higher at the end of the surgical procedure compared to values after the induction of anesthesia. The RM led to a significant increase in PaO2 in both groups without changes in HR or MAP. Conclusions: During laparoscopic cholecystectomy, the application of RM leads to a significant increase in Cstat and an improvement in gas exchange. The prevention of atelectasis during anesthesia should be initiated immediately after the induction of anesthesia, using protective mechanical ventilation and RM.

Ventilation strategy during urological and gynaecological robotic-assisted surgery: a narrative review

Robotic-assisted surgery has improved the precision and accuracy of surgical movements with subsequent improved outcomes. However, it requires steep Trendelenburg positioning combined with pneumoperitoneum that negatively affects respiratory mechanics and increases the risk of postoperative respiratory complications. This narrative review summarises the state of the art in ventilatory management of these patients in terms of levels of positive end-expiratory pressure (PEEP), tidal volume, recruitment manoeuvres, and ventilation modes during both urological and gynaecological robotic-assisted surgery. A review of the literature was conducted using PubMed/MEDLINE; after completing abstract and full-text review, 31 articles were included. Although different levels of PEEP were often evaluated within a protective ventilation strategy, including higher levels of PEEP, lower tidal volume, and recruitment manoeuvres vs a conventional ventilation strategy, we conclude that the best PEEP in terms of lung mechanics, gas exchange, and ventilation distribution has not been defined, but moderate PEEP levels (4-8 cm H2O) could be associated with better outcomes than lower or highest levels. Recruitment manoeuvres improved intraoperative arterial oxygenation, end-expiratory lung volume and the distribution of ventilation to dependent (dorsal) lung regions. Pressure-controlled compared with volume-controlled ventilation showed lower peak airway pressures with both higher compliance and higher carbon dioxide clearance. We propose directions to optimise ventilatory management during robotic surgery in light of the current evidence.

Reproductive Surgery in Females with Obesity: Reproductive Consequences of Obesity and Applications for Surgical Care

Obesity is the most common medical problem in women of reproductive age. The surgical applications for this population, many of who are interested in current or future fertility, are critical to safe and effective evaluation and management of issues that impact the reproductive system. As rates of obesity continue to rise worldwide, it is projected that one in two individuals will have obesity by 2030 leading to increasing numbers of individuals affected by a disease process that has implications for their gynecologic surgical care, fertility-related assessment, and infertility treatment. Offering patients with obesity access to safe reproductive surgery is a cornerstone of reproductive autonomy. This review will summarize current recommendations regarding surgical concepts for the operating room, office hysteroscopy, oocyte retrieval, and embryo transfer in female patients with obesity.

Predictive value of NoSAS questionnaire combined with the modified Mallampati grade for hypoxemia during routine sedation for gastrointestinal endoscopy

BACKGROUND

The incidence of hypoxemia during painless gastrointestinal endoscopy remains a matter of concem. To date, there is no recognized simple method to predict hypoxemia in digestive endoscopic anesthesia. The NoSAS (neck circumference, obesity, snoring, age, sex) questionnaire, an objective and simple assessment scale used to assess obstructive sleep apnea (OSA), combined with the modified Mallampati grade (MMP), may have certain screening value. This combination may allow anesthesiologists to anticipate, manage, and consequently decrease the occurrence of hypoxemia.

METHODS

This study was a prospective observational trial. The primary endpoint was the incidence of hypoxaemia defined as pulse oxygen saturation (SpO2) < 95% for 10 s. A total of 2207 patients admitted to our hospital for painless gastrointestinal endoscopy were studied. All patients were measured for age, height, weight, body mass index, neck circumference, snoring, MMP, and other parameters. Patients were divided into hypoxemic and non-hypoxemic groups based on the SpO2. The ROC curve was plotted to evaluate the screening value of the NoSAS questionnaire separately and combined with MMP for hypoxemia. The total NoSAS score was evaluated at cut-off points of 8 and 9.

RESULTS

With a NoSAS score ≥ 8 as the critical value for analysis, the sensitivity for hypoxemia was 58.3%, the specificity was 88.4%, and the area under the ROC was 0.734 (P < 0.001, 95% CI: 0.708-0.759). With a NoSAS score ≥ 9 as a critical value, the sensitivity for hypoxemia was 36.50%, the specificity rose to 96.16%, and the area under the ROC was 0.663 (P < 0.001, 95% CI: 0.639-0.688). With the NoSAS Score combined with MMP for analysis, the sensitivity was 78.4%, the specificity was 84%, and the area under the ROC was 0.859 (P < 0.001, 95%CI:0.834-0.883).

CONCLUSIONS

As a new screening tool, the NoSAS questionnaire is simple, convenient, and useful for screening hypoxemia. This questionnaire, when paired withMMP, is likely to be helpful for the screening of hypoxemia.

Lung mechanics during video-assisted abdominal surgery in Trendelenburg position: a cross-sectional propensity-matched comparison between classic laparoscopy and robotic-assisted surgery

BACKGROUND

Video-assisted surgery has become an increasingly used surgical technique in patients undergoing major thoracic and abdominal surgery and is associated with significant perioperative respiratory and cardiovascular changes. The aim of this study was to investigate the effect of intraoperative pneumoperitoneum during video-assisted surgery on respiratory physiology in patients undergoing robotic-assisted surgery compared to patients undergoing classic laparoscopy in Trendelenburg position.

METHODS

Twenty-five patients undergoing robotic-assisted surgery (RAS) were compared with twenty patients undergoing classic laparoscopy (LAS). Intraoperative ventilatory parameters (lung compliance and plateau airway pressure) were recorded at five specific timepoints: after induction of anesthesia, after carbon dioxide (CO₂) insufflation, one-hour, and two-hours into surgery and at the end of surgery. At the same time, arterial and end-tidal CO₂ values were noted and arterial to end-tidal CO₂ gradient was calculated.

RESULTS

We observed a statistically significant difference in plateau pressure between RAS and LAS at one-hour (26.2 ± 4.5 cmH₂O vs. 20.2 ± 3.5 cmH₂O, p = 0.05) and two-hour intervals (25.2 ± 5.7 cmH₂O vs. 17.9 ± 3.1 cmH₂O, p = 0.01) during surgery and at the end of surgery (19.9 ± 5.0 cmH₂O vs. 17.0 ± 2.7 cmH₂O, p = 0.02). Significant changes in lung compliance were also observed between groups at one-hour (28.2 ± 8.5 mL/cmH₂O vs. 40.5 ± 13.9 mL/cmH₂O, p = 0.01) and two-hour intervals (26.2 ± 7.8 mL/cmH₂O vs. 54.6 ± 16.9 mL/cmH₂O, p = 0.01) and at the end of surgery (36.3 ± 9.9 mL/cmH₂O vs. 58.2 ± 21.3 mL/cmH₂O, p = 0.01). At the end of surgery, plateau pressures remained higher than preoperative values in both groups, but lung compliance remained significantly lower than preoperative values only in patients undergoing RAS with a mean 24% change compared to 1.7% change in the LAS group (p = 0.01). We also noted a more significant arterial to end-tidal CO₂ gradient in the RAS group compared to LAS group at one-hour (12.9 ± 4.5 mmHg vs. 7.4 ± 4.4 mmHg, p = 0.02) and two-hours interval (15.2 ± 4.5 mmHg vs. 7.7 ± 4.9 mmHg, p = 0.02), as well as at the end of surgery (11.0 ± 6.6 mmHg vs. 7.0 ± 4.6 mmHg, p = 0.03).

CONCLUSION

Video-assisted surgery is associated with significant changes in lung mechanics after induction of pneumoperitoneum. The observed changes are more severe and longer-lasting in patients undergoing robotic-assisted surgery compared to classic laparoscopy.

Effect of inverse ratio ventilation on hemodynamics and respiratory mechanics in obese patients undergoing laparoscopic sleeve gastrectomy

Background

Obesity has become a global epidemic problem affecting every system and is associated with many consequences including coronary artery disease, hypertension, diabetes mellitus, dyslipidemia, obstructive sleep apnea, and socioeconomic and psychosocial impairment. Laparoscopic sleeve gastrectomy is one of the best and most commonly done operations for weight loss. Elevated peak airway pressure and hypoxemia are common problems that anesthesiologists face during laparoscopic surgeries with conventional volume-controlled ventilation. This study aimed at the use of the prolonged I:E ratio as an alternative strategy to improve gas exchange and the respiratory mechanics of obese patients undergoing laparoscopic sleeve gastrectomy.

Results

The study was a prospective randomized controlled trial and was performed between April 2019 and March 2020. After the approval of the departmental ethical committee and the informed written consent had been taken from the patients, fifty-two obese patients undergoing laparoscopic sleeve gastrectomy were enrolled in this study. After endotracheal intubation, the patients were randomly divided into the IRV group (n=26) and the VCV group (n=26). Respiratory parameters were adjusted as tidal volume (Vt) 8mL/kg ideal body weight, respiratory rate 12 breaths/min, positive-end expiratory pressure (PEEP) 0, fractional inspired oxygen (FiO₂) 0.6, and I:E ratio 1:2 for the VCV group and 2:1 for the IRV group; hemodynamics and respiratory mechanics were monitored and recorded after intubation (0 min), before pneumoperitoneum (10 mins), and after pneumoperitoneum (20 mins), 30, 40, 50, and 60 mins. IRV significantly improves the respiratory mechanics during pneumoperitoneum in the form of decreasing the peak pressure (Ppeak) and plateau pressure (Pplat) and improving the dynamic compliance, but the mean pressure (Pmean) was increased; it also increased the partial pressure of oxygen (arterial PO₂) significantly. No statistical significance was found regarding the demographic data or the hemodynamics.

Conclusion

IRV is superior to conventional VCV in morbidly obese patients undergoing laparoscopic sleeve gastrectomy as it improves respiratory mechanics and oxygenation.

Obesity parameters in relation to lung function levels in a large Chinese rural adult population

OBJECTIVES

The association between obesity parameters and lung function indicators in the general Chinese rural adult population remains unclear.

METHODS

In total, 8,284 Chinese adults aged 20 years to 80 years old from Xinxiang were recruited. Obesity-related parameters, including body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waistto-height ratio (WHtR), body fat percentage (BFP), basal metabolism, and visceral fat index, and lung function parameters such as forced vital capacity and forced expiratory volume in first second were measured.

RESULTS

The total prevalence of obesity defined by BMI, WC, WHR, WHtR, and BFP was 23.2%, 58.2%, 66.7%, 69.2%, and 56.5%, respectively. Spearman correlation analyses showed significant correlations between all obesity-related parameters and lung function. Linear regression analyses further demonstrated that BMI, WHtR, BFP, and general obesity defined using those indicators were negatively associated with lung function, while WC, WHR, and central obesity defined accordingly were positively associated with lung function. The relationship between general obesity and lung function was more evident in women than in men, while the link between central obesity and lung function was more obvious in men than in women.

CONCLUSIONS

Obesity is closely related to lung function in the general Chinese adult population. Weight control and loss are important strategies to improve lung function and respiratory health.

Intraoperative Monitoring of the Obese Patient Undergoing Surgery: A Narrative Review

With the increasing prevalence of obesity in the population, anaesthetists must confidently manage both the pathophysiological and technical challenges presented in bariatric and non-bariatric surgery. The intraoperative period represents an important opportunity to optimise and mitigate risk. However, there is little formal guidance on what intraoperative monitoring techniques should be used in this population. This narrative review collates the existing evidence for intraoperative monitoring devices in the obese patients. Although a number of non-invasive blood pressure monitors have been tested, an invasive arterial line remains the most reliable monitor if accurate, continuous monitoring is required. Goal-directed fluid therapy is recommended by clinical practice guidelines, but the methods tested to assess this had guarded applicability to the obese population. Transcutaneous carbon dioxide (CO₂) monitoring may offer additional benefit to standard capnography in this population. Individually titrated positive end expiratory pressure (PEEP) and recruitment manoeuvres improved intraoperative mechanics but yielded no benefit in the immediate postoperative period. Depth of anaesthesia monitoring appears to be beneficial in the perioperative period regarding recovery times and complications. Objective confirmation of reversal of neuromuscular blockade continues to be a central tenet of anaesthesia practice, particularly relevant to this group who have been characterised as an "at risk" extubation group. Where deep neuromuscular blockade is used, continuous neuromuscular blockade is suggested. Both obesity and the intraoperative context represent somewhat unstable search terms, as the clinical implications of the obesity phenotype are not uniform, and the type and urgency of surgery have significant impact on the intraoperative setting. This renders the generation of summary conclusions around what intraoperative monitoring techniques are suitable in this population highly challenging.

The Influence of the Metabolic Syndrome on Early Postoperative Outcomes of Patients With Advanced-stage Endometrial Cancer

BACKGROUND/AIM

Endometrial cancer is one of the most commonly encountered malignancies among obese women worldwide, a strong causality relationship being established between the two entities. Furthermore, obesity is also associated with metabolic syndrome; the aim of this study was to investigate the effect of metabolic syndrome on the postoperative outcomes of patients with endometrial cancer.

PATIENTS AND METHODS

Data of 23 patients diagnosed with endometrial cancer and metabolic syndrome were retrospectively reviewed and compared to the those of a control group of patients diagnosed with endometrial cancer in the absence of metabolic syndrome.

RESULTS

Patients in the first group presented significantly higher values of body mass index when compared to the control group. There were no significant differences in terms of stage, histopathological subtype or degree of differentiation between the two groups. The completeness of cytoreduction was lower among patients with metabolic syndrome, however, this did not reach statistical significance (p=0.08). Although the rate of complete debulking was lower among those with metabolic syndrome, the rates of postoperative complications were significantly higher.

CONCLUSION

The association of metabolic syndrome significantly influences the risk of postoperative complications in patients with endometrial cancer; moreover, in certain cases, it might preclude the achievement of freedom from residual disease.

Higher body mass index is associated with increased lung stiffness and less airway obstruction in individuals with asthma and fixed airflow obstruction

Persistent or fixed airflow obstruction (FAO) is prevalent in up to 60% of patients with severe asthma [1] and is associated with older age, more rapid decline in lung function and increased symptoms [1–3]. The underlying mechanisms of FAO in asthma are unknown, but growing evidence suggests that parenchymal changes resulting in loss of elastic recoil and decreased lung stiffness (i.e. increased lung compliance) contribute to FAO [2, 4]. In a recent study of older asthma patients with FAO, decreased lung stiffness was the sole predictor of more severe airflow obstruction, as measured by reduced forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio [2].

Higher body mass index (BMI) is associated with less severe airway obstruction in older asthma patients with fixed airflow obstruction. This is potentially mediated through BMI-related mechanisms that increase lung stiffness (i.e. reduce lung compliance).https://bit.ly/3jBwCNy

Emergency tracheal intubation during off-hours is not associated with increased mortality in hospitalized patients: a retrospective cohort study

Background

The prognosis of hospitalized patients after emergent endotracheal intubation (ETI) remains poor. Our aim was to evaluate the 30-d hospitalization mortality of subjects undergoing ETI during daytime or off-hours and to analyze the possible risk factors affecting mortality.

Methods

A single-center retrospective study was performed at a university teaching facility from January 2015 to December 2018. All adult inpatients who received ETI in the general ward were included. Information on patient demographics, vital signs, ICU (Intensive care unit) admission, intubation time (daytime or off-hours), the department in which ETI was performed (surgical ward or medical ward), intubation reasons, and 30-d hospitalization mortality after ETI were obtained from a database.

Results

Over a four-year period, 558 subjects were analyzed. There were more male than female in both groups (115 [70.1%] vs 275 [69.8%]; P = 0.939). A total of 394 (70.6%) patients received ETI during off-hours. The patients who received ETI during the daytime were older than those who received ETI during off-hours (64.95 ± 17.54 vs 61.55 ± 17.49; P = 0.037). The BMI of patients who received ETI during the daytime was also higher than that of patients who received ETI during off-hours (23.08 ± 3.38 vs 21.97 ± 3.25; P < 0.001). The 30-d mortality after ETI was 66.8% (373), which included 68.0% (268) during off-hours and 64.0% (105) during the daytime (P = 0.361). Multivariate Cox regression analysis found that the significant factors for the risk of death within 30 days included ICU admission (HR 0.312, 0.176–0.554) and the department in which ETI was performed (HR 0.401, 0.247–0.653).

Conclusions

The 30-d hospitalization mortality after ETI was 66.8%, and off-hours presentation was not significantly associated with mortality. ICU admission and ETI performed in the surgical ward were significant factors for decreasing the risk of death within 30 days.

Trial registration

This trial was retrospectively registered with the registration number of ChiCTR2000038549.

Factors affecting airway compliance and resistance in children receiving general anesthesia during adenotonsillectomy

Airway compliance is an important index in the surgery of pediatric patients. This study aimed to explore factors affecting dynamic airway compliance (Cdyn) and airway resistance (Raw) after general anesthesia endotracheal intubation for adenotonsillectomy of pediatric patients.A prospective study was undertaken of 107 children who underwent adenotonsillectomy in Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine between January and June 2018. The values of Cdyn and Raw were recorded at 5, 10, and 15 minute during general anesthesia endotracheal intubation. Univariate analysis and multiple linear regression analysis were performed for factors that affected Cdyn and Raw.Of the 107 patients aged 56.67 ± 18.28 months, 69 (64%) patients were male, and 26 (24%) and 12 (11%) had an upper respiratory infection in the past week and 1 to 2 weeks, respectively. During anesthesia, Cdyn showed a decreasing trend (P < .001) while Raw showed an increasing trend (P < .001). Multivariate analysis revealed that height (β=0.177-0.193) had the strongest correlation with Cdyn; rales during pulmonary auscultation (β= -2.727 to -1.363) and sputum suction (β= -1.670 to -0.949) were also associated with Cdyn (all P < .05). Height was the factor with the strongest negative correlation with Raw (β= -0.382 to -0.305). Rales during pulmonary auscultation (β=10.063-11.326) and sputum suction (β=3.863-9.003) were also associated with Raw (All P < .05).Height, rales during preoperative auscultation and sputum suction were all associated with intraoperative Cydn and Raw for pediatric patients undergoing adenotonsillectomy and should be considered before the surgery.

Body Habitus and Dynamic Surgical Conditions Independently Impair Pulmonary Mechanics during Robotic-assisted Laparoscopic Surgery

Background

Body habitus, pneumoperitoneum, and Trendelenburg positioning may each independently impair lung mechanics during robotic laparoscopic surgery. This study hypothesized that increasing body mass index is associated with more mechanical strain and alveolar collapse, and these impairments are exacerbated by pneumoperitoneum and Trendelenburg positioning.

Methods

This cross-sectional study measured respiratory flow, airway pressures, and esophageal pressures in 91 subjects with body mass index ranging from 18.3 to 60.6 kg/m2. Pulmonary mechanics were quantified at four stages: (1) supine and level after intubation, (2) with pneumoperitoneum, (3) in Trendelenburg docked with the surgical robot, and (4) level without pneumoperitoneum. Subjects were stratified into five body mass index categories (less than 25, 25 to 29.9, 30 to 34.9, 35 to 39.9, and 40 or higher), and respiratory mechanics were compared over surgical stages using generalized estimating equations. The optimal positive end-expiratory pressure settings needed to achieve positive end-expiratory transpulmonary pressures were calculated.

Results

At baseline, transpulmonary driving pressures increased in each body mass index category (1.9 ± 0.5 cm H2O; mean difference ± SD; P &lt; 0.006), and subjects with a body mass index of 40 or higher had decreased mean end-expiratory transpulmonary pressures compared with those with body mass index of less than 25 (–7.5 ± 6.3 vs. –1.3 ± 3.4 cm H2O; P &lt; 0.001). Pneumoperitoneum and Trendelenburg each further elevated transpulmonary driving pressures (2.8 ± 0.7 and 4.7 ± 1.0 cm H2O, respectively; P &lt; 0.001) and depressed end-expiratory transpulmonary pressures (–3.4 ± 1.3 and –4.5 ± 1.5 cm H2O, respectively; P &lt; 0.001) compared with baseline. Optimal positive end-expiratory pressure was greater than set positive end-expiratory pressure in 79% of subjects at baseline, 88% with pneumoperitoneum, 95% in Trendelenburg, and ranged from 0 to 36.6 cm H2O depending on body mass index and surgical stage.

Conclusions

Increasing body mass index induces significant alterations in lung mechanics during robotic laparoscopic surgery, but there is a wide range in the degree of impairment. Positive end-expiratory pressure settings may need individualization based on body mass index and surgical conditions.

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Feasibility and safety of laparoscopic approach in obese patients with endometriosis: a multivariable regression analysis

PURPOSE

To evaluate the feasibility and safety of laparoscopic excision of endometriotic lesions in obese women.

METHODS

Retrospective analysis of prospectively collected data involving consecutive women scheduled for complete laparoscopic removal of macroscopic endometriotic lesions between January 2012 and November 2018. Operative time, laparotomic conversion rates, complication rates, and length of hospital stay were recorded.

RESULTS

One thousand two hundred thirty women were enrolled and divided into two main groups, according to the World Health Organization classification of obesity, obese (body mass index ≥ 30 kg/m²) and non-obese (body mass index < 30 kg/m²). During the study period, 91 (7.4% of overall study cohort) obese women underwent surgery. At univariate analyses, significant differences between the two groups were found in terms of age, rates of severe endometriosis, American Society of Anesthesiologists physical status classification ≥ III, and different surgical procedures. Significant differences in terms of median operative time [125 (interquartile range (IQR) 85-165) in obese group vs 110 min (IQR 75-155) in non-obese group, P = 0.04] were observed. There were no significant differences between the obese and non-obese groups with respect to the other variables of interest. After adjusted multivariable regression models for potential confounders, difference in operating time (coefficient of 13.389; 95% CI 1.716, 25.060) was still found to be significant.

CONCLUSION

In our tertiary care referral center, laparoscopic removal of endometriosis is feasible and safe, except for a slight increase of operative time and conversion rate.

The impact of obesity on pulmonary deterioration in patients undergoing robotic-assisted laparoscopic prostatectomy

Obesity affects respiratory and hemodynamic function in anesthetized patients. The aim of this study was to evaluate the influence of the body mass index (BMI) on pulmonary changes in a permanent 45° steep Trendelenburg position (STP) during robotic-assisted laparoscopic prostatectomy (RALP). 51 patients undergoing RALP under standardized anesthesia were included. Perioperative pulmonary function and oxygenation were measured in awake patients (T₀), 20 min after the induction of anesthesia (T₁), after insufflation of the abdomen in supine position (T₂), after 30 min in STP (T₃), when controlling Santorini's plexus in STP (T₄), before awakening while supine (T₅), and after 45 min in the recovery room (T₆). Patient-specific and time-dependent factor on ventilation and predicted peak inspiratory pressure (PIP), driving pressure (P_driv) and lung compliance (LC) in a linear regression model were calculated. PIP and P_driv increased significantly after induction of capnoperitoneum (T_2-4) (p < 0.0001). In univariate mixed effects models, BMI was found to be a significant predictor for PIP and P_driv increase and LC decrease. Obese patients a BMI > 31 kg/m² reached critical PIP values ≥ 35 cmH₂O. Postoperative oxygenation represented by the PaO₂/FiO₂ ratio was significantly decreased compared to T₀ (p < 0.0001). Obesity in combination with STP and capnoperitoneum during RALP has a profound effect on pulmonary function. Increased PIP and P_driv and decreased LC are directly correlated with a high BMI. Changes in PIP, P_driv and LC during RALP may be predicted in relation to patient's BMI for consideration in the preoperative setting. Trial registration number Z-2014-0387-6. Registered on 8 July 2014.

Journal of Clinical Monitoring and Computing 2017 end of year summary: respiration

This paper reviews 32 papers or commentaries published in Journal of Clinical Monitoring and Computing in 2016, within the field of respiration. Papers were published covering airway management, ventilation and respiratory rate monitoring, lung mechanics and gas exchange monitoring, in vitro monitoring of lung mechanics, CO₂ monitoring, and respiratory and metabolic monitoring techniques.

Robot-assisted gynaecological cancer surgery-complications and prevention

Ever since the US Food and Drug Administration approval of the use of da Vinci surgical systems (Intuitive Surgical Inc., Sunnyvale, California) in gynaecology in 2005, robot-assisted surgery has been widely adopted in different countries. Some of the applications in benign and oncological gynaecology include myomectomy, sacrocolpopexy, tubal anastomosis, simple hysterectomy, radical hysterectomy, radical trachelectomy, pelvic and/or para-aortic lymphadenectomy and even debulking surgery for ovarian cancer and pelvic exenteration for recurrent cervical and vaginal cancer. Although there is robust evidence on the safety and treatment outcomes in robot-assisted surgery, complications still rarely occur. Team approach is particularly important in robotic surgery and thorough communication between the bedside assistant and the console surgeon cannot be stressed any more. Thus, complications can be due to miscommunication between the console surgeon and bedside assistant, positioning of the patients, the length of the operations, the malfunction of the instrument and the risks specific to the types of anaesthesia and surgery per se, leading to thromboembolism, haemorrhage, organ damage, and so on. The most important strategies that can prevent complications are to have thorough preoperative assessment of the patients' fitness, good communication between surgical team members, caution regarding the positioning, a good knowledge of the pelvic and abdominal anatomy, careful and meticulous manipulation of the instrument and early recognition of the complications. In this article, different types of complications and the preventive measures are described.