Peri-operative management of the obese surgical patient 2015: Association of Anaesthetists of Great Britain and Ireland Society for Obesity and Bariatric Anaesthesia

Spinal anesthesia in ambulatory patients

PURPOSE OF THIS REVIEW

To assess current practice in the use of spinal anesthesia in major ambulatory surgery, highlighting its advantages over general anesthesia and identifying potential areas for improvement to facilitate a transition to a sustainable healthcare system.

RECENT FINDINGS

Spinal anesthesia might be preferred in selected populations when compared to general anesthesia providing the highest standards of healthcare quality.The use of local anesthetics with short half-life has proven to be efficient in achieving high anesthesia success rates. Spinal anesthesia does not increase perioperative complications; instead, it has shown a reduction in postoperative nausea and vomiting, an improvement in patient comfort, and a favorable economic impact when compared to general anesthesia.

SUMMARY

Spinal anesthesia is an appropriate method for anesthesia in ambulatory patients, offering advantages over general anesthesia in selected populations.The use of spinal anesthesia is expanding to meet surgical needs. Therefore, it is crucial to plan ahead and anticipate organizational failures in the ambulatory setting to maintain safety and efficiency during outpatient procedures and surgeries.

Pharmacokinetics of propofol in severely obese surgical patients

BACKGROUND

Existing PK models of propofol include sparse data from very obese patients. The aim of this study was to develop a PK model based on standardised surgical conditions and spanning from normal-weight up to, and including, a high number of very obese patients.

METHODS

Adult patients scheduled for laparoscopic cholecystectomy or bariatric surgery were studied. Anaesthesia was induced with propofol 2 mg/kg adjusted body weight over 2 min followed by 6 mg/kg/h adjusted body weight over 30 min. For the remainder of the operation anaesthesia was maintained with sevoflurane. Remifentanil was dosed according to clinical need. Eight arterial samples were drawn in a randomised block sampling regimen over a span of 24 h. Time-concentration data were analysed by population PK modelling using non-linear mixed-effects modelling.

RESULTS

Four hundred and seventy four serum propofol concentrations were collected from 69 patients aged 19-60 years with a BMI 21.6-67.3 kg/m2. Twenty one patients had a BMI above 50 kg/m2. A 3-compartment PK model was produced wherein three different body weight descriptors and sex were included as covariates in the final model. Total body weight was found to be a covariate for clearance and Q3; lean body weight for V1, V2 and Q2; predicted normal weight for V3 and sex for V1. The fixed allometric exponent of 0.75 applied to all clearance parameters improved the performance of the model. Accuracy and precision were 1.4% and 21.7% respectively in post-hoc performance evaluation.

CONCLUSION

We have developed a new PK model of propofol that is suitable for all adult weight classes. Specifically, it is based on data from an unprecedented number of individuals with very high BMI.

Pre-oxygenation with high-flow oxygen through the nasopharyngeal airway compared to facemask on carbon dioxide clearance in emergency adults: a prospective randomized non-blinded clinical trial

INTRODUCTION

Before tracheal intubation, it is essential to provide sufficient oxygen reserve for emergency patients with full stomachs. Recent studies have demonstrated that high-flow nasal oxygen (HFNO) effectively pre-oxygenates and prolongs apneic oxygenation during tracheal intubation. Despite its effectiveness, the use of HFNO remains controversial due to concerns regarding carbon dioxide clearance. The air leakage and unknown upper airway obstruction during HFNO therapy cause reduced oxygen flow above the vocal cords, possibly weaken the carbon dioxide clearance.

METHODS

Patients requiring emergency surgery who had fasted < 8 h and not drunk < 2 h were randomly assigned to the high-flow group, who received 100% oxygen at 30-60 L/min through nasopharyngeal airway (NPA), or the mask group, who received 100% oxygen at 8 L/min. PaO2 and PaCO2 were measured immediately before pre-oxygenation (T0), anesthesia induction (T1), tracheal intubation (T2), and mechanical ventilation (T3). The gastric antrum's cross-sectional area (CSA) was measured using ultrasound technology at T0, T1, and T3. Details of complications, including hypoxemia, reflux, nasopharyngeal bleeding, postoperative pulmonary infection, postoperative nausea and vomiting (PONV), and postoperative nasopharyngeal pain, were recorded. The primary outcomes were PaCO2 measured at T1, T2, and T3. The secondary outcomes included PaO2 at T1, T2, and T3, CSA at T1 and T3, and complications happened during this trial.

RESULTS

Pre-oxygenation was administered by high-flow oxygen through NPA (n = 58) or facemask (n = 57) to 115 patients. The mean (SD) PaCO2 was 32.3 (6.7) mmHg in the high-flow group and 34.6 (5.2) mmHg in the mask group (P = 0.045) at T1, 45.0 (5.5) mmHg and 49.4 (4.6) mmHg (P < 0.001) at T2, and 47.9 (5.1) mmHg and 52.9 (4.6) mmHg (P < 0.001) at T3, respectively. The median ([IQR] [range]) PaO2 in the high-flow and mask groups was 404.5 (329.1-458.1 [159.8-552.9]) mmHg and 358.9 (274.0-413.3 [129.0-539.1]) mmHg (P = 0.007) at T1, 343.0 (251.6-428.7 [73.9-522.1]) mmHg and 258.3 (162.5-347.5 [56.0-481.0]) mmHg (P < 0.001) at T2, and 333.5 (229.9-411.4 [60.5-492.4]) mmHg and 149.8 (87.0-246.6 [51.2-447.5]) mmHg (P < 0.001) at T3, respectively. The CSA in the high-flow and mask groups was 371.9 (287.4-557.9 [129.0-991.2]) mm2 and 386.8 (292.0-537.3 [88.3-1651.7]) mm2 at T1 (P = 0.920) and 452.6 (343.7-618.4 [161.6-988.1]) mm2 and 385.6 (306.3-562.0 [105.5-922.9]) mm2 at T3 (P = 0.173), respectively. The number (proportion) of complications in the high-flow and mask groups is shown below: hypoxemia: 1 (1.7%) vs. 9 (15.8%, P = 0.019); reflux: 0 (0%) vs. 0 (0%); nasopharyngeal bleeding: 1 (1.7%) vs. 0 (0%, P = 1.000); pulmonary infection: 4 (6.9%) vs. 3 (5.3%, P = 1.000); PONV: 4 (6.9%) vs. 4 (7.0%, P = 1.000), and nasopharyngeal pain: 0 (0%) vs. 0 (0%).

CONCLUSIONS

Compared to facemasks, pre-oxygenation with high-flow oxygen through NPA offers improved carbon dioxide clearance and enhanced oxygenation prior to tracheal intubation in patients undergoing emergency surgery, while the risk of gastric inflation had not been ruled out.

TRIAL REGISTRATION

This trial was registered prospectively at the Chinese Clinical Research Registry on 26/4/2022 (Registration number: ChiCTR2200059192).

2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

Pharmacokinetics and exposure-safety relationship of ciprofol for sedation in mechanically ventilated patients in the intensive care unit

Ciprofol (HSK3486) is a newly developed, highly selective γ-aminobutyric acid-A (GABAA) receptor potentiator that is recently approved for a new indication of sedation for patients in the intensive care unit (ICU) in China. This analysis aimed to characterize the population pharmacokinetics (PopPKs) of ciprofol and evaluate the relationship of exposure with hypotension in mechanically ventilated patients in the ICU. A total of 462 subjects with 3918 concentration measurements from two clinical trials of mechanically ventilated patients in the ICU, four clinical trials of elective surgical patients, and six clinical trials of healthy subjects were used in the PopPK analysis. Exposure-safety relationship for hypotension was evaluated based on the data gathered from 112 subjects in two clinical trials of mechanically ventilated patients in the ICU. Ciprofol pharmacokinetics (PKs) was adequately described by a three-compartment linear disposition model with first-order elimination. Body weight, age, sex, blood sampling site (vein vs. arterial), study design (long-term infusion vs. short-term infusion), and patient population (ICU vs. non-ICU) were identified as statistically significant covariates on the PKs of ciprofol. Within the exposure range of the mechanically ventilated ICU patient population, no meaningful association was observed between ciprofol exposure and the incidence of hypotension. These results support the dosing regimen currently used in mechanically ventilated patients in the ICU.

Obesity at term: What to consider? How to deliver?

Obesity presents significant challenges during pregnancy, increasing the risk of complications and adverse outcomes for both mother and baby. With the rising prevalence of obesity among pregnant women, questions arise regarding optimal management, including timing of delivery and choice of delivery mode. Labour induction in obese women may require a combination of mechanical and pharmacological methods due to increased risk of failed induction. Caesarean section in obese women presents unique challenges, requiring comprehensive perioperative planning and specialized care to optimize outcomes. However, specific guidelines tailored to obese patients undergoing caesarean sections are lacking. Postpartum care should include vigilant monitoring for complications. Addressing obesity in pregnancy necessitates a multidisciplinary approach and specialized care to ensure the best outcomes.

Airway and respiratory complications during anaesthesia and associated with peri-operative cardiac arrest as reported to the 7th National Audit Project of the Royal College of Anaesthetists

The 7th National Audit Project (NAP7) of the Royal College of Anaesthetists studied complications of the airway and respiratory system during anaesthesia care including peri-operative cardiac arrest. Among 24,721 surveyed cases, airway and respiratory complications occurred commonly (n = 421 and n = 264, respectively). The most common airway complications were: laryngospasm (157, 37%); airway failure (125, 30%); and aspiration (27, 6%). Emergency front of neck airway was rare (1 in 8370, 95%CI 1 in 2296-30,519). The most common respiratory complications were: severe ventilation difficulty (97, 37%); hyper/hypocapnia (63, 24%); and hypoxaemia (62, 23%). Among 881 reports to NAP7 and 358 deaths, airway and respiratory complications accounted for 113 (13%) peri-operative cardiac arrests and 32 (9%) deaths, with hypoxaemia as the most common primary cause. Airway and respiratory cases had higher and lower survival rates than other causes of cardiac arrest, respectively. Patients with obesity, young children (particularly infants) and out-of-hours care were overrepresented in reports. There were six cases of unrecognised oesophageal intubation with three resulting in cardiac arrest. Of these cases, failure to correctly interpret capnography was a recurrent theme. Cases of emergency front of neck airway (6, approximately 1 in 450,000) and pulmonary aspiration (11, approximately 1 in 25,000) leading to cardiac arrest were rare. Overall, these data, while distinct from the 4th National Audit Project, suggest that airway management is likely to have become safer in the last decade, despite the surgical population having become more challenging for anaesthetists.

Waist-to-height ratio is a better predictor of hypertension in women during recovery from anesthesia compared to BMI, waist-to-hip ratio, and waist circumference

This was an observational study of patients with benign breast tumors intended to investigate and compare the predictive value of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) for hypertension in the recovery room. Logistic regression analysis was used to determine the association between these body fat anthropometric indices and hypertension. Receiver operating characteristic curve (ROC) analysis was performed to assess the comparative predictive ability. A total of 689 women were evaluated. Patients with BMI ≥28 (kg/m2), WC > 85 cm, WHR ≥0.82, and WHtR ≥0.5 had a significantly higher probability of increased systolic blood pressure (SBP) and diastolic blood pressure (DBP) than patients with less than threshold values (all P < 0.05). The areas under the ROC curve (AUC) of BMI, WC, and WHtR where all modestly significant (all AUC ≥0.65) and nearly identical at 0.6592, 0.65, and 0.6724, respectively. Conclusion: body fat anthropometric indices are useful predicting hypertension during recovery from general anesthesia in patients with benign breast tumors undergoing day surgery; WHtR outperformed the other indices and nearly identical.

The effect of age on clinical dose equivalency of fentanyl and morphine analgosedation in mechanically ventilated patients: Findings from the ANALGESIC trial

BACKGROUND

The dose equivalency of fentanyl vs. morphine is widely considered to be approximately 1:100. However, little is known about the effect of age on this ratio when these agents are used as infusions for analgosedation.

OBJECTIVES

To assess the impact of age on the clinical dose equivalency of fentanyl and morphine when used as infusions for analgosedation in mechanically ventilated intensive care unit patients.

METHODS

We performed a post hoc analysis of the Assessment of Opioid Administration to Lead to Analgesic Effects and Sedation in Intensive Care (ANALGESIC) cluster randomised crossover trial of fentanyl and morphine infusions for analgosedation. Dose and analgosedative clinical equivalency of fentanyl and morphine were assessed by age and by using different body-size descriptors.

RESULTS

We studied 663 patients (338 fentanyl, 325 morphine). Median (interquartile range) hourly dose of fentanyl and morphine were 58.1 (40.0-89.2) mcg and 3400 (2200-5000) mcg, respectively. The ratio of total dose of fentanyl:morphine was 1:93 in the 18- to 29-year-old group and 1:25 in the ≥80-year-old group (p = 0.015), respectively, with fentanyl becoming relatively less clinically effective as age increased. This effect was also seen when comparing dosing by different body-size descriptors with the strongest age-related change when using body surface area as body-size descriptor (p = 0.009).

CONCLUSION

The analgosedative clinical dose equivalency of fentanyl vs. morphine is heterogeneous when used as infusions for analgosedation, with fentanyl becoming relatively less clinically effective as age increases. This information can help guide prescription of these agents during transition from one agent to the other in critically ill patients.

Feasibility of same-day discharge after laparoscopic sleeve gastrectomy in the Netherlands

BACKGROUND

There is a trend towards laparoscopic sleeve gastrectomy (SG) with same-day discharge (SDD), as an efficient healthcare pathway to alleviate the burden on clinical capacity. This approach seems to be safe, if patients are carefully selected. In our bariatric center, a protocol for Roux-en-Y gastric bypass with SDD has already been successfully implemented. The aim of this study was to evaluate feasibility of applying the same SDD protocol for SG.

METHODS

A single-center prospective feasibility study was conducted at a high-volume bariatric center. Low-risk patients who were scheduled for primary SG were included. Strict criteria were used for approval upon SDD. The primary outcome was the rate of successful SDD without readmission within 48 h. Secondary outcomes included short-term complications, emergency department visits, readmissions, and mortality.

RESULTS

Fifty patients were included in the study, of whom 45 were successfully discharged on the same day of the surgery. Nausea and vomiting were the most common reasons for overnight hospitalization (three patients). One patient was readmitted within the first 48 h due to a mild complication related to bleeding, resulting in a success rate of 88% for SDD without readmission within 48 h. No severe complications or mortality were reported in the cohort.

CONCLUSION

Our SDD protocol for SG has demonstrated feasibility, with a high success rate of SDD and no severe complications. Strict conditions should be met for the safe implementation of a SDD protocol, including careful patient selection and the establishment of a safety net to detect early complications.

Surgical transversus abdominis plane block with liposomal bupivacaine at cesarean: a pilot randomized trial

BACKGROUND

Postcesarean pain control is challenging. In addition to intrathecal morphine, recent studies have shown that liposomal bupivacaine administered via conventional transversus abdominis plane block reduces postcesarean opioid use. However, whether the administration of liposomal bupivacaine via a surgical approach also reduces opioid use is unknown.

OBJECTIVE

This study aimed to investigate whether the administration of liposomal bupivacaine via surgical transversus abdominis plane block (TAP block) reduces the cumulative dose of opioids administered in the first 48 hours after cesarean delivery among participants who also receive intrathecal morphine.

STUDY DESIGN

This was a pilot single-blind randomized controlled trial of 60 parturients undergoing cesarean delivery at a community tertiary referral hospital staffed by academic physicians. Immediately before fascial closure during cesarean delivery, a total of 80 mL of dilute bupivacaine plus liposomal bupivacaine or dilute bupivacaine alone was administered via surgical transversus abdominis plane block (40 mL on each side). The primary outcome was a median cumulative opioid dose received within the first 48 hours after cesarean delivery measured in morphine milligram equivalents. In addition, opioid use at other time points, pain scores, and participant satisfaction were assessed. A sample size of 60 was determined to be adequate to inform a potential future adequately powered randomized trial. The primary outcome of morphine milligram equivalents and pain scores were compared using a Wilcoxon rank-sum test.

RESULTS

Between October 11, 2021, and August 29, 2022, 60 participants were randomized and analyzed: 31 were allocated to liposomal bupivacaine plus regular bupivacaine (intervention group), and 29 were allocated to regular bupivacaine alone (control group). Participants allocated to the intervention group used a median cumulative dose of 2 morphine milligram equivalents of opioids (interquartile range, 0-24) in the first 48 hours compared with 8 morphine milligram equivalents (interquartile range, 0-40) among participants allocated to the control group (P=.236). The percentage of participants who used ≤15 morphine milligram equivalents of opioids was 61% in the intervention arm and 41% in the control arm (P=.123), and the percentage who used zero opioids was 45% in the intervention arm and 34% in the control arm (P=.399). The total number of opioid pills prescribed at discharge was fewer in the intervention arm than in the control arm (P=.029). Patient satisfaction with the intervention group and control group was similar.

CONCLUSION

Our pilot study suggests that liposomal bupivacaine administered via surgical transversus abdominis plane block is worth critical evaluation as an adjunctive analgesic modality in an adequately powered randomized trial.

Airway management of lingual tonsillar hypertrophy: A narrative review

Lingual tonsillar hypertrophy is rarely identified on routine airway assessment but may cause difficulties in airway management. We conducted a narrative review of case reports of lingual tonsillar hypertrophy to examine associated patient factors, success rates of airway management techniques and complications. We searched the literature for anaesthetic management of cases with lingual tonsillar hypertrophy. We found 89 patients in various case reports, from which we derived 92 cases to analyse. 64% of cases were assessed as having a normal airway. Difficult and impossible face mask ventilation occurred in 29.6% and 1.4% of cases, respectively. Difficult intubation and failed intubation occurred in 89.1% and 21.7% of cases, respectively. Multiple attempts (up to six) at intubation were performed, with no successful intubation after the third attempt with direct laryngoscopy. Some 16.5% of patients were woken up and 4.3% required emergency front of neck access. Complications included oesophageal intubation (10.9%), bleeding (9.8%) and severe hypoxia (3.2%). Our findings show that severe cases of lingual hypertrophy may cause an unanticipated difficult airway and serious complications, including hypoxic brain damage and death. A robust airway strategy is required which includes limiting the number of attempts at laryngoscopy, and early priming and performance of emergency front of neck access if required. In patients with known severe lingual tonsillar hypertrophy, awake intubation should be considered.

Bed tilt and ramp positions are associated with increased first-pass success of adult endotracheal intubation in the emergency department: A registry study

OBJECTIVE

Successful endotracheal intubation in the ED requires optimum body positioning. In patients with obesity, the ramp position was suggested to achieve better intubating conditions. However, limited data are available on the airway management practices for patients with obesity in Australasian EDs. The aim of this study was to identify current patient positioning practices during endotracheal intubation and its association with first-pass success (FPS) at intubation and adverse event (AE) rates in obese and non-obese populations.

METHODS

Prospectively collected data from the Australia and New Zealand ED Airway Registry (ANZEDAR) between 2012 and 2019 were analysed. Patients were categorised into two groups according to their weight: <100 kg (non-obese) or ≥100 kg (obese). Four position categories were investigated; supine, pillow or occipital pad, bed tilt and ramp or head-up with relation to FPS and complication rate using logistic regression modelling.

RESULTS

A total of 3708 intubations from 43 EDs were included. Overall, the non-obese cohort had a greater FPS rate (85.9%) compared to the obese group (77.0%). The bed tilt position had the highest FPS rate (87.2%), whereas the supine position had the lowest (83.0%). AE rates were highest in the ramp position (31.2%) compared to all other positions (23.8%). Regression analysis showed ramp, or bed tilt positions and a consultant-level intubator were associated with higher FPS. Obesity, in addition to other factors, was independently associated with lower FPS.

CONCLUSION

Obesity was associated with lower FPS, which could be improved through performing a bed tilt or ramp positioning.

Anesthesia for Morbidly Obese Patients

BACKGROUND

The prevalence of morbid obesity (BMI >35 kg/m2) has risen steadily in recent decades. With the corresponding rise in the number of bariatric operations, anesthesiologists deal with this patient group more commonly than before, particularly in specialized centers.

METHODS

This review is based on publications retrieved by a selective search in PubMed, including current guidelines and recommendations issued by specialist societies, as well as expert opinion.

RESULTS

In the anesthesiological care of morbidly obese patients, a preoperative assessment and risk stratification are just as important as the thoughtful selection of the anesthesia technique, the drugs used and their dosage, and perioperative management. A thorough understanding of the pathophysiological changes and comorbidities of morbid obesity and the associated risks is essential. The risk of pulmonary complications such as respiratory failure, hypoxia, and apnea is markedly higher in morbidly obese patients, especially those with obstructive sleep apnea. Short-acting, less lipophilic anesthetic drugs are particularly useful, as is multimodal pain therapy for the avoidance of high opiate doses. The indication for intensified postoperative monitoring depends on the patient's preexisting illnesses, the type of anesthesia, and the type of surgical procedure. Regional anesthetic techniques should be used if possible.

CONCLUSION

The perioperative care of morbidly obese patients presents special challenges. The anesthesiologist must be aware of potential comorbidities, specific risks, and pathophysiological changes in order to provide adequate care to this patient group.

Perioperative management of Obstructive Sleep Apnoea: Present themes and future directions

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is an increasingly common pathology that all those involved in perioperative care will come across. Patients with the condition present a challenge at many stages along the perioperative journey, not least because many patients living with OSA are unaware of their diagnosis.Key interventions can be made pre, intra-, and postoperatively to improve outcomes. Knowledge of screening tools, diagnostic tests, and the raft of treatment options are important for anyone caring for these patients.

RECENT FINDINGS

Recent literature has highlighted the increasing complexity of surgical patients and significant underdiagnosis of OSA in this patient population. Work has demonstrated how and why patients with OSA are at a higher perioperative risk and that effective positive airways pressure (PAP) therapy can reduce these risks, alongside evidencing how best to optimise adherence to therapy, a key issue in OSA.

SUMMARY

OSA, and particularly undiagnosed OSA, presents a huge problem in the perioperative period. Perioperative PAP reduces the risk of postoperative complications but adherence remains an issue. Bespoke perioperative pathways should be developed to identify and optimise high risk patients, although at present evidence on how best to achieve this is lacking.

Propofol-remifentanil patient-controlled sedation for endoscopic procedures: a prospective service audit

PURPOSE

Following demand, we established a patient-controlled propofol-remifentanil sedation service for endoscopy overseen by an anesthesiologist. To assess the effectiveness of the intervention of this service and any complications, we prospectively audited the service. Our primary outcomes of interest were adequacy of sedation and patient satisfaction. Secondary outcomes included any adverse events associated with the sedation.

METHODS

Patients were referred for failure of procedure under endoscopist-administered sedation, refusal of procedure without general anesthesia (GA), or planned complex procedure. We included all 670 procedures performed between 2017 and 2021. We used a mixture of 8.9 mg·mL-1 propofol and 5.4 µg·mL-1 remifentanil with a 1-mL bolus and 20-sec lockout. We assessed the adequacy of sedation using the Modified Gloucester Scale and categorized adverse events according to the Tracking and Reporting Outcomes of Procedural Sedation.

RESULTS

All 670 procedures were accomplished with adequate sedation without the need for ventilation or GA, and all patients were satisfied with the sedation. The complication rate was low, with no sentinel airway or respiratory events. Nineteen out of 670 patients (2.8%) had an incidence of airway obstruction (requiring a simple airway maneuver). The body mass index (BMI) was documented in 18/19 of these patients and the average BMI in this group was 35 kg·m-2. Seven of the 670 patients (1%) had self-terminating apnea, 3/670 patients (0.4%) vomited, no patients aspirated, and 17/665 patients (2.6%) required a vasopressor to maintain blood pressure within 20% of preprocedure values.

CONCLUSION

The results from our prospective service audit indicate that propofol-remifentanil patient-controlled sedation is a safe and reliable technique in patients undergoing endoscopic procedures.

Effect of Sevoflurane on the Deep Neuromuscular Blockade in Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy: A Single Center Prospective Randomized Controlled Study

Objective

Our study aimed to demonstrate that the combination of sevoflurane inhalation with continuous intravenous anesthesia can effectively reduce the dosage of muscle relaxants, shorten extubation time under anesthesia while meeting the requirements of laparoscopic deep neuromuscular block (dNMB) in obese patients. Additionally, we sought to assess the potential reduction in postoperative residual muscle relaxants.

Methods

Fifty-nine patients were randomly assigned. Anesthesia-related variables, such as anesthetics dosages, muscle relaxant effective time, clinical muscle relaxant time, muscle relaxant in vivo action time, muscle relaxant recovery time, body movement times, and extubation duration were recorded. Surgery-related variables (the Leiden-Surgical Rating Scale (L-SRS), duration of the procedure) were recorded. Pain was measured using the visual analog scale (VAS) score before leaving the PACU. The duration of the PACU stay and patients' satisfaction levels in the PACU were also recorded.

Results

Patients who inhaled sevoflurane during the operation required a lower dosage of muscle relaxant to achieve the same deep neuromuscular block (dNMB) effect. The time from stopping the rocuronium pump to T1 recovery of 90% was shorter, and the time for T1 to recover from 25% to 75% was faster among patients who inhaled sevoflurane during the operation. Furthermore, the sevoflurane combined with continuous intravenous anesthesia group exhibited a shorter extubation time for obese patients undergoing laparoscopic bariatric surgery, along with a reduced risk of experiencing hypoxemia and a shorter observation time in the PACU.

Conclusion

Inhaling sevoflurane combined with continuous intravenous anesthesia during the operation effectively reduces the dosage of muscle relaxant required to achieve the same deep neuromuscular block (dNMB) effect. Additionally, this approach significantly shortens the extubation time for obese patients undergoing laparoscopic bariatric surgery and reduces the risk of experiencing hypoxemia, along with reducing the observation time in the PACU.

Individualized Positive End-expiratory Pressure Titration Strategies in Superobese Patients Undergoing Laparoscopic Surgery: Prospective and Nonrandomized Crossover Study

BACKGROUND

Superobesity and laparoscopic surgery promote negative end-expiratory transpulmonary pressure that causes atelectasis formation and impaired respiratory mechanics. The authors hypothesized that end-expiratory transpulmonary pressure differs between fixed and individualized positive end-expiratory pressure (PEEP) strategies and mediates their effects on respiratory mechanics, end-expiratory lung volume, gas exchange, and hemodynamic parameters in superobese patients.

METHODS

In this prospective, nonrandomized crossover study including 40 superobese patients (body mass index 57.3 ± 6.4 kg/m2) undergoing laparoscopic bariatric surgery, PEEP was set according to (1) a fixed level of 8 cm H2O (PEEPEmpirical), (2) the highest respiratory system compliance (PEEPCompliance), or (3) an end-expiratory transpulmonary pressure targeting 0 cm H2O (PEEPTranspul) at different surgical positioning. The primary endpoint was end-expiratory transpulmonary pressure at different surgical positioning; secondary endpoints were respiratory mechanics, end-expiratory lung volume, gas exchange, and hemodynamic parameters.

RESULTS

Individualized PEEPCompliance compared to fixed PEEPEmpirical resulted in higher PEEP (supine, 17.2 ± 2.4 vs. 8.0 ± 0.0 cm H2O; supine with pneumoperitoneum, 21.5 ± 2.5 vs. 8.0 ± 0.0 cm H2O; and beach chair with pneumoperitoneum; 15.8 ± 2.5 vs. 8.0 ± 0.0 cm H2O; P < 0.001 each) and less negative end-expiratory transpulmonary pressure (supine, -2.9 ± 2.0 vs. -10.6 ± 2.6 cm H2O; supine with pneumoperitoneum, -2.9 ± 2.0 vs. -14.1 ± 3.7 cm H2O; and beach chair with pneumoperitoneum, -2.8 ± 2.2 vs. -9.2 ± 3.7 cm H2O; P < 0.001 each). Titrated PEEP, end-expiratory transpulmonary pressure, and lung volume were lower with PEEPCompliance compared to PEEPTranspul (P < 0.001 each). Respiratory system and transpulmonary driving pressure and mechanical power normalized to respiratory system compliance were reduced using PEEPCompliance compared to PEEPTranspul.

CONCLUSIONS

In superobese patients undergoing laparoscopic surgery, individualized PEEPCompliance may provide a feasible compromise regarding end-expiratory transpulmonary pressures compared to PEEPEmpirical and PEEPTranspul, because PEEPCompliance with slightly negative end-expiratory transpulmonary pressures improved respiratory mechanics, lung volumes, and oxygenation while preserving cardiac output.

EDITOR’S PERSPECTIVE

Intravenous Lidocaine Decreased the Median Effective Concentration of Sufentanil for Tracheal Intubation in Obese Patients

Purpose

Sufentanil has been widely used to inhibit the hemodynamic responses caused by tracheal intubation. Using intravenous lidocaine may reduce the dose of sufentanil and better maintain the hemodynamics. This study aimed to determine the effects of intravenous lidocaine on the median effective concentration (EC50) of sufentanil for endotracheal intubation in obese patients.

Patients and Methods

This is a randomized, double-blind, up-and-down sequential allocation study. Fifty obese patients undergoing bariatric surgery were randomly allocated in a 1:1 ratio into the lidocaine group and the saline group. Anesthesia was induced using a target-controlled infusion of propofol and sufentanil. The effect-site concentration (Ce) of propofol was 3.5 μg/mL. The Ce of sufentanil for the first patient was 0.4 ng/mL, and the sufentanil dose for the next patient was determined according to the responses of the previous patient, using Dixon's up-and-down sequential method with an interval of 0.05 ng/mL. When the target concentration of propofol and sufentanil was reached, lidocaine 1.5 mg/kg or the same volume of normal saline was infused over 3 min. Tracheal intubation was performed 3 min after the end of the lidocaine or normal saline infusion. Probit regression was used to calculate the EC50 and 95% confidence interval (CI) of sufentanil.

Results

Thirty-eight patients completed this study. The EC50 of sufentanil was 0.36 ng/mL (95% CI: 0.31-0.41 ng/mL) in the lidocaine group, which was significantly lower than 0.50 ng/mL (95% CI: 0.43-0.62 ng/mL) in the saline group. In addition, compared with saline group, the dosage of sufentanil in lidocaine group decreased significantly during the test. The hemodynamics of the two groups were stable during the study period.

Conclusion

Intravenous lidocaine 1.5 mg/kg decreased the EC50 of sufentanil required for tracheal intubation in obese patients undergoing bariatric surgery.

Anaesthetic nurse specialist role in perioperative anaesthetic management of patients who are morbidly obese

This integrative literature review examined the role of an anaesthetic nurse specialist (ANS) in the perioperative anaesthetic nursing management of morbidly obese patients associated with elective orthopaedic surgery. The responsibility of the ANS is to provide high-quality perioperative anaesthetic care to ensure patient safety. Morbid obesity is increasing globally, with significant implications for healthcare delivery, care and treatment, including perioperative care. The Association of Anaesthetists of Great Britain and Ireland emphasises that the perioperative management of these patients presents significant organisational and practical issues. However, there are limited data or guidelines on whether surgeons, anaesthetists and nurses routinely take special precautions in managing morbidly obesity patients undergoing elective orthopaedic operative procedures. The authors carried out a search of databases, followed by an integrated literature review and synthesis of 11 studies. The main findings revealed significant clinical challenges and resource requirements for perioperative anaesthetic management of this patient group. Recommendations are made to prepare for and manage these surgical patients, from preoperative assessment to postoperative care.

Feasibility of Same-Day Discharge After Laparoscopic Roux-en-Y Gastric Bypass in Patients with Well-Regulated Obstructive Sleep Apnea

INTRODUCTION

Same-day discharge after bariatric surgery is increasingly being performed. In current practice, patients with only minor comorbidities are considered eligible for same-day discharge after laparoscopic Roux-en-Y gastric bypass (RYGB). Obstructive sleep apnea (OSA) is a common comorbidity in patients with morbid obesity, with a prevalence of around 70-80% among patients undergoing bariatric surgery. Continuous positive airway pressure (CPAP) is the current gold standard treatment for OSA. We aimed to investigate whether same-day discharge after RYGB is feasible for patients with compliant use of CPAP.

METHODS

In this single-center prospective feasibility study, patients were selected who were scheduled for RYGB and were adequately treated for OSA. Compliance on the use of CPAP had to be proved (> 4 h per night for 14 consecutive nights). There were strict criteria on approval upon same-day discharge. The primary outcome was the rate of successful same-day discharge. Secondary outcomes included short-term complications, emergency department presentations, readmissions, and mortality.

RESULTS

Forty-nine patients underwent RYGB with intended same-day discharge, of whom 45 (92%) were successfully discharged. Three patients had an overnight stay because of divergent vital signs and one patient due to a delayed start of the surgery. Two patients (4%) were readmitted in the first 48 h postoperatively, both due to intraluminal bleeding which was managed conservatively (Clavien-Dindo 2). There were no severe complications in the first 48 h after surgery.

CONCLUSION

Same-day discharge after RYGB can be considered feasible for selected patients with well-regulated OSA.

Same-Day Discharge After Laparoscopic Roux-en-Y Gastric Bypass: a Cohort of 500 Consecutive Patients

INTRODUCTION

There is an increasing demand on hospital capacity worldwide due to the COVID-19 pandemic and local staff shortages. Novel care pathways have to be developed in order to keep bariatric and metabolic surgery maintainable. Same-day discharge (SDD) after laparoscopic Roux-en-Y gastric bypass (RYGB) is proved to be feasible and could potentially solve this challenge. The aim of this study was to investigate whether SDD after RYGB is safe for a selected group of patients.

METHODS

In this single-center cohort study, low-risk patients were selected for primary RYGB with intended same-day discharge with remote monitoring. All patients were operated according to ERAS protocol. There were strict criteria on approval upon same-day discharge. It was demanded that patients should contact the hospital in case of any signs of complications. Primary outcome was the rate of successful same-day discharge without readmission within 48 h. Secondary outcomes included short-term complications, emergency department visits, readmissions, and mortality.

RESULTS

Five hundred patients underwent RYGB with intended SDD, of whom 465 (93.0%) were successfully discharged. Twenty-one patients (4.5%) were readmitted in the first 48 h postoperatively. None of these patients had a severe bleeding. This results in a success rate of 88.8% of SDD without readmission within 48 h.

CONCLUSIONS

Same-day discharge after RYGB is safe, provided that patients are carefully selected and strict discharge criteria are used. It is an effective care pathway to reduce the burden on hospital capacity.

Five-year follow-up after pancreatoduodenectomy performed for malignancy: A single-centre study

Backgrounds/Aims

The aim of this study was to describe short- and long-term outcomes of patients who underwent pancreatoduodenectomy (PD) at a typical United Kingdom hepatopancreatobiliary unit.

Methods

A retrospective analysis of all PD patients with histologically-confirmed pancreatic ductal adenocarcinoma (PDAC), ampullary adenocarcinoma (AA), or distal cholangiocarcinoma (CC) from September 1st, 2006 to May 31st, 2015 was carried out. The following information was obtained: demographics, comorbidities, preoperative investigations, neoadjuvant treatment, operative details, postoperative management, complications, adjuvant treatment, five-year recurrence, and five-year survival. Effects of selected preoperative variables on short- and long-term outcomes were investigated.

Results

Of 271 included patients, 57.9% had PDAC, 25.8% had AA, and 16.2% had CC. In total, 67.9% experienced morbidity and 17.3% developed a Clavien-Dindo grade ≥ III complication. The 90-day mortality was 3.3%. Clinically-relevant postoperative pancreatic fistula, bile leak, gastrojejunal leak, postpancreatectomy haemorrhage and delayed gastric emptying affected 8.1%, 4.1%, 0.0%, 9.2%, and 19.9% of patients, respectively. American Society of Anesthesiologists grade III-VI correlated with overall morbidity (p = 0.002) and major morbidity (p = 0.009), but not 90-day mortality or five-year survival. The same pattern was observed in patients with a preoperative serum bilirubin > 29 μmol/L and/or a neutrophil/lymphocyte ratio > 3.1. Five-year cancer recurrence and five-year survival were 68.3% and 22.5%, respectively. PDAC patients had higher five-year recurrence but lower five-year survival rates (both p = 0.001).

Conclusions

In our series, the majority of patients experienced a complication. However, few patients experienced major morbidity. Surgical risk factors did not affect five-year survival.

[Anesthesia in obesity surgery : Recommendations from the practice for the practice]

BACKGROUND

Due to unsuccessful conservative treatment concepts and the steady increase in the prevalence of obesity, obesity surgery has gained importance worldwide. In Germany alone, around 20,000 surgical operations for obesity are performed each year. In addition to patient history and physical examination a close interdisciplinary cooperation taking into account the currently applicable standards and guidelines of the professional societies are prerequisites for best patient care and to evaluate and mitigate patient risks.

AIM

The aim of this work was to compile and consent experiences of experts in the implementation of applicable standards and guidelines for anesthesia in obesity surgery for daily clinical practice.

METHOD

Anesthesiologists from five bariatric centers, comprising about 10% of the obesity surgery caseload of Germany per year, have collated their clinical experiences to agree on a consensus for procedures. The procedures for preoperative patient evaluation, drug premedication and PONV prophylaxis, induction of anesthesia and drug dosage recommendations for anesthetics were consented based on the authors' practice.

RESULTS AND CONCLUSION

The procedures described herein were developed as part of a joint work process. The authors describe a practically applicable approach to the anesthesiological care of obesity surgery patients and recommend using a pragmatic formula for dosing the medication calculated on the basis of total body weight (TBW).

Ramped versus sniffing position in the videolaryngoscopy-guided tracheal intubation of morbidly obese patients: a prospective randomized study

BACKGROUND

Ramped positioning is recommended for intubating obese patients undergoing direct laryngoscopy. However, whether the use of the ramped position can provide any benefit in videolaryngoscopy-guided intubation remains unclear. This study assessed intubation time using videolaryngoscopy in morbidly obese patients in the ramped versus sniffing positions.

METHODS

This is a prospective randomized study in patients with morbid obesity (n = 82; body mass index [BMI] ≥ 35 kg/m2). Patients were randomly allocated to either the ramped or the standard sniffing position groups. During the induction of general anesthesia, difficulty in mask ventilation was assessed using the Warters scale. Tracheal intubation was performed using a C-MAC® D-Blade videolaryngoscope, and intubation difficulty was assessed using the intubation difficulty scale (IDS). The primary endpoint was the total intubation time calculated as the sum of the laryngoscopy and tube insertion times.

RESULTS

The percentage of difficult mask ventilation (Warters scale ≥ 4) was significantly lower in the ramped (n = 40) than in the sniffing group (n = 41) (2.5% vs. 34.1%, P < 0.001). The percentage of easy intubation (IDS = 0) was significantly higher in the ramped than in the sniffing group (70.0% vs. 7.3%, P < 0.001). The total intubation time was significantly shorter in the ramped than in the sniffing group (22.5 ± 6.2 vs. 40.9 ± 9.0, P < 0.001).

CONCLUSIONS

Compared with the sniffing position, the ramped position reduced intubation time in morbidly obese patients and effectively facilitated both mask ventilation and tracheal intubation using videolaryngoscopy.

Thromboembolic Complications After Bariatric Surgery: Is the High Risk Real?

INTRODUCTION

Nowadays, a large number of bariatric surgery (BS) procedures are undertaken worldwide as surgery has become an efficient strategy to treat the obesity epidemic. The risk of venous thromboembolism (VTE) is increased in patients undergoing BS not only due to the intrinsic surgical risk but also because patients with obesity have a 2-3-fold higher risk of VTE. The optimal strategy for VTE prevention in BS setting, including optimal dose and thromboprophylaxis regimen, is still not fully clarified. The aim of this study was to report a bariatric high-volume center experience and to propose a practical thromboprophylaxis protocol for this population.

METHODS

A single-center, observational, retrospective, and longitudinal study was conducted from January 2018 to December 2020, a total of 901 patients who underwent primary and revisional bariatric surgery were included.

RESULTS

The overall frequency of VTE events was 0.44% (n=4), one patient had pulmonary embolism (PE) during index hospital admission; another patient had simultaneous deep venous thrombosis (DVT) and PE, two months after surgery; and two other patients had DVT, nine and 16 months after surgery. The median time for VTE was four months. The incidence of females was 75% (n=3) and the median age was 57 years. Only one female patient was using oral contraception. None had a previous history of thromboembolic events, chronic venous insufficiency, or other known diseases that could increase the VTE risk.

CONCLUSION

Considering the outcomes reported by this experienced center with low rates of thromboembolic events, we suggest a thromboprophylaxis protocol that can be easily applied to the majority of bariatric patients.

Apnoeic oxygenation in morbid obesity: a randomised controlled trial comparing facemask and high-flow nasal oxygen delivery

BACKGROUND

Obesity is a risk factor for airway-related incidents during anaesthesia. High-flow nasal oxygen has been advocated to improve safety in high-risk groups, but its effectiveness in the obese population is uncertain. This study compared the effect of high-flow nasal oxygen and low-flow facemask oxygen delivery on duration of apnoea in morbidly obese patients.

METHODS

Morbidly obese patients undergoing bariatric surgery were randomly allocated to receive either high-flow nasal (70 L min^-1) or facemask (15 L min^-1) oxygen. After induction of anaesthesia, the patients were apnoeic for 18 min or until peripheral oxygen saturation decreased to 92%.

RESULTS

Eighty patients were studied (41 High-Flow Nasal Oxygen, 39 Facemask). The median apnoea time was 18 min in both the High-Flow Nasal Oxygen (IQR 18-18 min) and the Facemask (inter-quartile range [IQR], 4.1-18 min) groups. Five patients in the High-Flow Nasal Oxygen group and 14 patients in the Facemask group desaturated to 92% within 18 min. The risk of desaturation was significantly lower in the High-Flow Nasal Oxygen group (hazard ratio=0.27; 95% confidence interval [CI], 0.11-0.65; P=0.007).

CONCLUSIONS

In experienced hands, apnoeic oxygenation is possible in morbidly obese patients, and oxygen desaturation did not occur for 18 min in the majority of patients, whether oxygen delivery was high-flow nasal or low-flow facemask. High-flow nasal oxygen may reduce desaturation risk compared with facemask oxygen. Desaturation risk is a more clinically relevant outcome than duration of apnoea. Individual physiological factors are likely to be the primary determinant of risk rather than method of oxygen delivery.

CLINICAL TRIAL REGISTRATION

NCT03428256.

Oxford guidelines for adult day-case tonsillectomy

Oxford guidelines were developed after critically reviewing the existing literature and aim to assist anaesthetists, surgeons and allied healthcare staff in providing optimal care for patients undergoing tonsillectomy as a day-case procedure. Appropriate patient selection, provision of robust analgesia, antiemesis, perioperative warming and hydration are key factors to ensure patient comfort and allow same-day discharge. Patients can be discharged home after a minimum observation of 6h as this is the period with the greatest risk of primary haemorrhage. All patients must have a clear and safe understanding of which complications may occur and know how to seek help. A team effort and close collaboration between the anaesthetic, surgical, theatre and ward teams are essential to achieve optimum outcomes and reduce the rate of failed discharges.

The Role of Thromboprophylaxis in Patients with Portal Vein Thrombosis: A Life-Threatening Complication after Laparoscopic Sleeve Gastrectomy Following 8 Years of Experience in a Bariatric Center of Excellence

Porto-mesenteric vein thrombosis (PVMT) is a rare but life-threatening complication after laparoscopic sleeve gastrectomy (LSG). Laparoscopic sleeve gastrectomy (LSG) is considered the most common procedure for efficiently realizing weight loss and treating obesity-related co-morbidities. This study aimed to shed light on this relatively rare complication by presenting a series of patients who developed PMVT after LSG in light of the need to change the specific protocol of thromboprophylaxis in bariatric patients. We proposed to answer two questions: whether we should perform a thrombophilia workup as a standard practice and whether we should extend chemoprophylaxis to more than 3 weeks among all bariatric patients. This study also aimed to investigate the possible risk factors and eventually present our updated protocol for PMVT management and prophylaxis.

Development and Validation of a Nomogram for Predicting Postoperative Pulmonary Infection in Patients Undergoing Lung Surgery

OBJECTIVES

To develop and validate a nomogram for predicting postoperative pulmonary infection (PPI) in patients undergoing lung surgery.

DESIGN

Single-center retrospective cohort analysis.

SETTING

A university-affiliated cancer hospital PARTICIPANTS: A total of 1,501 adult patients who underwent lung surgery from January 2018 to December 2020.

INTERVENTIONS

Observation for PPI within 7 days after lung surgery.

MEASUREMENTS AND MAIN RESULTS

A complete set of demographics, preoperative variables, and postoperative follow-up data was recorded. The primary outcome was PPI; a total of 125 (8.3%) out of 1,501 patients developed PPI. The variables with p < 0.1 in univariate logistic regression were included in the multivariate regression, and multivariate logistic regression analysis showed that surgical procedure, surgical duration, the inspired fraction of oxygen in one-lung ventilation, and postoperative pain were independent risk factors for PPI. A nomogram based on these factors was constructed in the development cohort (area under the curve: 0.794, 95% CI 0.744-0.845) and validated in the validation cohort (area under the curve: 0.849, 95% CI 0.786-0.912). The calibration slope was 1 in the development and validation cohorts. Decision curve analysis indicated that when the threshold probability was within a range of 0.02-to-0.58 and 0.02-to-0.42 for the development and validation cohorts, respectively, the nomogram model could provide a clinical net benefit.

CONCLUSIONS

The authors developed and validated a nomogram for predicting PPI in patients undergoing lung surgery. The prediction model can predict the development of PPI and identify high-risk groups.

The Prehospital Emergency Anaesthetic in 2022

Prehospital emergency anesthesia (PHEA) is a commonly performed prehospital procedure with inherent risks. The processes and drug regimens behind PHEA are continually updated by prehospital teams across the country as part of their governance structure. Essex & Herts Air Ambulance has recently updated this practice by reviewing the entire process of performing PHEA. Through experiential learning in a high-volume service, audit, and a contemporary literature review, a new standard operating procedure has been developed to combat common problems, such as hypotension, associated with the more traditional methods of performing PHEA. The aim of this article was to summarize the literature behind this new standard operating procedure, systematically breaking down the core components of performing a PHEA and the rationale behind them. The key components identified in the review are indications for PHEA, airway assessment, peri-intubation oxygenation, preparation for PHEA, drug dosing, special circumstances, and failed intubation. One significant change is the drug dosage regimen; 1 μg/kg fentanyl, 2 mg/kg ketamine, and 2 mg/kg rocuronium is recommended as the main drug dosing regimen for both medical and trauma patients. Other changes include preoxygenation with a nasal cannula in addition to the nonrebreather mask, optimizing patients in the preparation phase by considering inopressors or fluid bolus and ensuring a "sterile cockpit" to control the surrounding environment to ensure the first intubation attempt is the best attempt.

Dilemmas Related to Direct-Acting Oral Anticoagulant Administration in Patients With Extreme Obesity

OBJECTIVE

The objective of the study was to discuss the controversies surrounding the use and dosing of direct-acting oral anticoagulants (DOACs) in obese patients recognizing the limitations of the existing evidence base that preclude strong recommendations.

DATA SOURCES

A literature search of MEDLINE was performed (2020 to end August 2022) subsequent to recent guidelines using the following search terms: direct acting anticoagulants, obesity, rivaroxaban, apixaban, edoxaban, dabigatran, dabigatran etexilate, and clinical practice guidelines.

STUDY SELECTION AND DATA ABSTRACTION

English-language studies and those conducted in adults were selected.

DATA SYNTHESIS

The available randomized studies evaluating DOACs had relatively small numbers of patients with more extreme forms of obesity (body mass index [BMI] > 40 kg/m²) and none of the larger studies had a specific focus on dosing DOACs in obese patients. Recent guidelines by the International Society on Thrombosis and Haemostasis (ISTH) have specific recommendations for dosing DOACs in obesity. There are pharmacokinetic/pharmacodynamic and observational studies published before and after the ISTH guidelines with a focus on DOAC dosing in obese patients that generally support the recommendations in the guidelines, but most involved small numbers of patients usually with BMIs <45 kg/m².

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review discusses DOAC dosing in obesity with important considerations for clinicians related to DOAC choice and dosing.

CONCLUSIONS

Dosing alterations of DOACs do not appear to be necessary when used for either prophylaxis or treatment in patients with BMIs up to approximately 45 to 50 kg/m², but research is needed for BMIs >50 kg/m².

Perioperative Management of Robotic-Assisted Gynecological Surgery in a Super Morbidly Obese Patient

We report the perioperative management of a 32-year-old woman with super-morbid obesity (body mass index (BMI) of 60.9 kilograms per meter squared (kg/m²)) who underwent a robotic-assisted total laparoscopic hysterectomy in a hospital that was not specialized for obese patients. She successfully reduced her BMI by 10% using dietary restrictions in five weeks, and her surgery was performed two weeks later by consultation between gynecologists and anesthesiologists. This case demonstrates that the determination of the optimal time for surgery by consultation between physicians is crucial in the care of such a complex patient in hospitals that are not specialized for morbidly obese patients. Weight reduction in the preoperative period should be considered for super-morbid obesity patients with malignant diseases, even if the duration of preoperative optimization is shorter than four to eight weeks.

Obstructive sleep apnoea and perioperative medicine: a growing concern

Obstructive sleep apnoea represents a sizable public health and economic burden. Owing to rising obesity rates, the prevalence of obstructive sleep apnoea is increasing, and it is a condition that is significantly underdiagnosed. Exacerbated by the COVID-19 pandemic, the backlog of elective surgeries is also sizable and growing. A combination of these factors means that many patients due to have surgery will have obstructive sleep apnoea, either diagnosed or otherwise.

Patients with obstructive sleep apnoea have a significantly increased risk of operative complications, but the evidence base for optimum perioperative management of these patients is limited. This article reviews sleep apnoea, its prevalence and its impact on operative management and perioperative outcomes for patients. The evidence base for screening and treating undiagnosed obstructive sleep apnoea is also comprehensively assessed. Finally, a pathway to manage patients with possible undiagnosed obstructive sleep apnoea is proposed, and areas for further research identified.

Development and Validation of a Length- and Habitus-Based Method of Ideal and Lean Body Weight Estimation for Adults Requiring Urgent Weight-Based Medical Intervention

BACKGROUND AND OBJECTIVE

Accurate drug dosing in obese patients requires an estimation of ideal body weight (IBW) or lean body weight (LBW) for dosing hydrophilic medications. Erroneous weight estimates during the management of adults requiring weight-based treatment may contribute to poor outcomes. Existing methods of IBW and LBW estimation or measurement are very difficult to use during emergency care. A new point-of-care model would be useful to provide rapid estimates of IBW and LBW for this purpose.

METHODS

A model was derived based on the PAWPER XL-MAC tape, a pediatric weight estimation system which uses recumbent length and mid-arm circumference to estimate IBW and LBW. The new adult model was used to generate IBW and LBW estimations for a derivation sample (n = 33155) and a validation sample (n = 5926) from National Health and Nutrition Examination Survey (NHANES) datasets. The model was developed in two steps, with calibration at each step, before being validated on an unused dataset. The outcome measure was to achieve >95% of IBW and LBW estimations within 20% of recognized reference standards (P20 > 95%) and >70% of estimations within 10% of these standards (P10 > 70%).

RESULTS

The new model achieved a P20 of 100% and a P10 of 99.9% for IBW and a P20 of 98.3% and a P10 of 78.3% for LBW. This accuracy was maintained in both sexes, all ages, all ethnic groups, all lengths, and in all habitus types, except for the severely obese female subgroup.

CONCLUSIONS

The modified PAWPER XL-MAC model proved to be an accurate method of IBW and LBW estimation. It could, therefore, have an important role in facilitating emergency drug dose calculations in obese adult patients.

The Impact of Goal-Directed Fluid Therapy on Postoperative Nausea and Vomiting in High-Risk Patients Undergoing Laparoscopic Sleeve Gastrectomy

PURPOSE

Patients with laparoscopic sleeve gastrectomy (LSG) are at high risk of postoperative nausea and vomiting (PONV). Goal-directed fluid therapy (GDFT) has been proven effective in improving postoperative gastrointestinal function in patients with obesity, but its effect on prevention of PONV remains controversial. This study aimed to investigate the impact of GDFT on PONV in high-risk patients with LSG.

METHODS

In a randomized, single-blinded, two-arm trial, patients with an Apfel score ≥ 3 and scheduled for LSG were included. Patients in the GDFT group received stroke volume-guided fluid therapy. Patients in the control group received conventional fluid therapy. The primary outcome was the incidence of PONV within 48 h after LSG. The second outcome included intensity of PONV, use of rescue therapy, recovery of gastrointestinal function, and postoperative length of stay (LOS).

RESULTS

A total of 137 patients were analyzed. The incidence of PONV in the GDFT group was lower than that in the control group (47.1% vs. 71.6%; odds ratio [95%CI], 0.35 [0.17-0.72]; P = 0.004). Fewer patients in the GDFT group received rescue therapy (30% vs. 58.2%; P = 0.001). Patients following GDFT protocol had a faster return of flatus (27.5 (19, 31) vs. 31 (20, 48) hours, P = 0.037) and shorter postoperative LOS (6.1 ± 1.0 vs. 6.6 ± 1.1 days; P = 0.007).

CONCLUSION

GDFT is conducive to deceasing PONV occurrence, restoring intestinal function, and shortening postoperative LOS in high-risk patients undergoing LSG.

Enhanced recovery after bariatric surgery: an Italian consensus statement

Background

Enhanced recovery after bariatric surgery (ERABS) is an approach developed to improve outcomes in obese surgical patients. Unfortunately, it is not evenly implemented in Italy. The Italian Society for the Surgery of Obesity and Metabolic Diseases and the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care joined in drafting an official statement on ERABS.

Methods

To assess the effectiveness and safety of ERABS and to develop evidence-based recommendations with regard to pre-, intra-, and post-operative care for obese patients undergoing ERABS, a 13-member expert task force of surgeons and anesthesiologists from Italian certified IFSO center of excellence in bariatric surgery was established and a review of English-language papers conducted. Oxford 2011 Levels of Evidence and U.S. Preventive Services Task Force Grade Definitions were used to grade the level of evidence and the strength of recommendations, respectively. The supporting evidence and recommendations were reviewed and discussed by the entire group at meetings to achieve a final consensus.

Results

Compared to the conventional approach, ERABS reduces the length of hospital stay and does not heighten the risk of major post-operative complications, re-operations, and hospital re-admissions, nor does it increase the overall surgical costs. A total of 25 recommendations were proposed, covering pre-operative evaluation and care (7 items), intra-operative management (1 item, 11 sub-items), and post-operative care and discharge (6 items).

Conclusions

ERABS is an effective and safe approach. The recommendations allow the proper management of obese patients undergoing ERABS for a better outcome.

Accuracy of Oxygen Saturation Measurements in Patients with Obesity Undergoing Bariatric Surgery

BACKGROUND

We aimed to determine the magnitude, direction, and influencing factors of the concordance between arterial oxygen saturation (SaO₂) and peripheral capillary oxygen saturation (SpO₂) in patients with obesity undergoing bariatric surgery, supporting the measurement of SaO₂ and SpO₂ in key populations.

METHODS

Patients with obesity undergoing bariatric surgery from 2017 to 2020 were included. Preoperative SpO₂ and SaO₂ were collected. Linear correlation and multiple linear regression analyses were performed to characterize the relationships between body mass index (BMI), age, and sex with pulse oximetry and arterial blood gas (ABG) parameters. Bland-Altman analysis was applied to determine the concordance between SpO₂ and SaO₂ and the limits of this concordance.

RESULTS

A total of 134 patients with obesity undergoing bariatric surgery were enrolled. SaO₂ was negatively associated with BMI (p < 0.0001) and age (p = 0.006), and SpO₂ was negatively associated with BMI (p = 0.021) but not with age. SpO₂ overestimated SaO₂ in 91% of patients with a bias of 2.05%. This bias increased by 203% in hypoxemic patients compared with nonhypoxemic patients (p < 0.0001). The bias was 1.3-fold higher (p = 0.023) in patients with a high obesity surgery mortality risk score (OS-MRS) than in those with low or intermediate scores.

CONCLUSION

Compared with SpO₂, preoperative SaO₂ can more accurately reflect the real oxygen saturation in patients with obesity undergoing bariatric surgery, especially for those with BMI ≥ 40 kg/m², age ≥ 40 years, and high OS-MRS. ABG analysis can provide a more reliable basis for accurate and timely monitoring, ensuring the perioperative safety of susceptible patients.

Effect of Intraperitoneal Local Anesthetics in Laparoscopic Bariatric Surgery: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

The effectiveness of intraperitoneal local anesthesia (IPLA) has been confirmed in other fields, but its use in bariatric surgery remains debatable. This study aimed to evaluate the analgesic effect of IPLA in bariatric surgery.

METHODS

PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to February 2022. All randomized controlled trials (RCTs) assessing IPLA's analgesic effect in bariatric surgery were included in this study. Pain-related indicators were the outcome.

RESULTS

Ten RCTs with 979 patients were included. Postoperative pain scores were significantly lower in IPLA group. Subgroup analysis demonstrated that IPLA was associated with lower pain scores in 6 h and at 24 h compared to the control group, without significant differences at 8, 12, and 48 h. Meanwhile, IPLA reduced the dose of opioids taken postoperatively. Additionally, there were no differences in adverse events between the two groups. As far as the number of postoperative analgesics used and hospital stays were concerned, our results did not show statistical differences between the two groups.

CONCLUSION

IPLA can reduce postoperative pain safely and effectively, particularly during the early postoperative stage.

Cardiac surgery in the morbidly obese

BACKGROUND

Obesity rates globally continue to rise and in turn the body mass index (BMI) of patients undergoing cardiac surgery is set to mirror this. Patients who are Class III obese (BMI ≥ 40) pose significant challenges to the surgical teams responsible for their care and are also at high risk of complications from surgery and even death. To improve outcomes in this population, interventions carried out in the preoperative, operative, and postoperative periods have shown promise. Despite this, there are no defined best practice national guidelines for perioperative management of obese patients undergoing cardiac surgery.

AIM

This review is aimed at clinicians and researchers in the field of cardiac surgery and aims to form a basis for the future development of clinical guidelines for the management of obese cardiac surgery patients.

METHODS

The PubMed database was utilized to identify relevant literature and strategies employed at various stages of the surgical journey were analyzed.

CONCLUSIONS

Data presented identified the benefits of preoperative respiratory muscle training, off-pump coronary artery bypass grafting where possible, and early extubation. Further randomized controlled trials are required to identify optimal operative and perioperative management strategies before the introduction of such guidance into clinical practice.

Systematic review of randomized control trials into effective preoperative weight loss interventions and impact on surgical outcomes for major benign gynecological surgery

AIMS

Limited information exists on what preoperative weight loss interventions (lifestyle, pharmacological, surgical) are effective in improving outcomes of elective, nononcological, gynecological surgery. Obesity rates are increasing and associated with poorer operative outcomes. We aimed to identify high quality studies into preoperative weight loss interventions and perform a systematic review of the literature to guide recommendations for reducing gynecological surgical complications and guide future research. Primary outcomes were mortality and surgical complications including conversion to open surgery, duration of surgery, and recovery.

METHODS

The review was pre-registered with PROPSERO. A systematic search was undertaken of the major electronic bibliographic databases. Search results were compiled and abstracts of studies identified before application of the Cochrane highly sensitive search strategy (CHSSS) were reviewed. Full text of studies after application of the CHSSS were evaluated for suitability. For data collection and analysis, a minimum three high-quality randomized control trials were required to synthesize data in relation to the primary outcome.

RESULTS

No trials met the inclusion criteria. No randomized control trials in gynecological cohorts were identified. Studies in gynecology-oncology were excluded due to the confounding nature of weight loss as a feature of illness as opposed to health optimization.

CONCLUSION

There is limited evidence regarding preoperative weight loss interventions in gynecology. Further research is needed as the prevalence of obesity among women is increasing and definitive surgical management options in gynecology remain essential. PROSPERO registration ID: 165643.

A review on the anesthetic management of obese patients undergoing surgery

There has been an observed increase in theprevalence of obesity over the past few decades. The prevalence of anesthesiology related complications is also observed more frequently in obese patients as compared to patients that are not obese. Due to the increased complications that accompany obesity, obese patients are now more often requiring surgical interventions. Therefore, it is important that anesthesiologists be aware of this development and is equipped to manage these patients effectively and appropriately. As a result, this review highlights the effective management of obese patients undergoing surgery focusing on the preoperative, perioperative and postoperative care of these patients.

Patient selection for ambulatory laparoscopic cholecystectomy: A systematic review

Background

Currently, there is no consensus on patient selection for ambulatory laparoscopic cholecystectomy (LC). This study is a systematic review of previously published patient selection for ambulatory LC.

Methods

A comprehensive search was done in PubMed, Web of Science, Embase and Google Scholar Database up to March 2020 to summarise previously reported medical or surgical selection criteria used for inclusion and exclusion of patients, as well as successful same-day discharge rates and readmission rate after discharge.

Results

Fifty-nine studies with a total of 13,219 patients were included in this systematic review. In total, the median same-day discharge rate was 90% (range: 63%-99.4%), and median readmission rate was 2.22% (range: 0%-16.9%). The most considered medical criteria were American Society of Anesthesiologists classification I and II, age <70, and body mass index <35. Surgical criteria varied greatly. The top three accessible exclusion variables were (1) common bile duct stones, cholangitis, or jaundice (27 publications, 45.8%); (2) history of abdominal surgery (12 publications, 20.3%) and (3) history of pancreatitis (9 publications, 15.3%).

Conclusion

The results of the current study showed the variable patient selection in different centres, the medical aspect criteria may be expanded under adequate pre-anaesthetic assessment and preparation and the surgical aspect criteria should include more laboratory or imaging parameters to ensure the surgical safety.

Adopting the day surgery default in the provision of lumbar discectomy and decompressive surgery

INTRODUCTION

Provision of day case spinal procedures in the UK is below expected standards and there is a need for the creation of guidance and patient pathways to address this. Here we present a day case lumbar discectomy protocol and evaluate its impact at our institution.

METHODS

A new pathway (incorporating defined selection criteria, patient education, anaesthetic protocol and discharge prescriptions) was implemented for all suitable patients within a single surgeon's cohort. Day case rates for lumbar discectomy were compared before and after implementation. Patient feedback was collated using a patient-reported experience measure.

RESULTS

Eighteen of 23 patients selected as suitable via the pathway successfully underwent day surgery, leading to an increase in lumbar discectomy day case rates from 25% to 69% at our institution. Nearly all patients were satisfied with their experience, although a significant proportion felt provision of postoperative analgesia could be improved.

CONCLUSION

We present a day surgery pathway for lumbar discectomy that is safe and effective. This could be more widely implemented to increase day case rates.

Comparing postinduction hypoxemia between ramped and supine position endotracheal intubations with apneic oxygenation in the emergency department

INTRODUCTION

Ramped position and apneic oxygenation are strategies to mitigate hypoxemia; however, the benefits of these strategies when utilized together remain unclear. Therefore, we compared first-attempt, postinduction hypoxemia between adult emergency department (ED) endotracheal intubations performed with apneic oxygenation in the ramped versus supine positions.

METHODS

We used the National Emergency Airway Registry (NEAR), a multicenter registry of data on ED intubations from 25 academic and community sites. We included first-attempt intubations with direct (DL) and video (VL) laryngoscopy in subjects ≥ 18 years old with nontrauma indications receiving apneic oxygenation. We examined patient characteristics (e.g., sex, obesity) and key intubation outcomes, including hypoxemia (primary outcome), first-pass success, and other adverse events (e.g., bradycardia). In addition, we examined unadjusted odds ratios (OR) and adjusted ORs (aOR) for key variables and stratified by laryngoscope type.

RESULTS

We included 210 ramped cases and 1,820 supine cases in the DL cohort and 202 ramped and 1,626 supine cases in the VL cohort. Rates of postinduction hypoxemia were similar between supine and ramped position in both the DL cohort (supine 6.5% and ramped 7.6%, aOR [95% CI] = 0.96 [0.55 to 1.67]) and the VL cohort (supine 10.1% and ramped 12.4%, aOR [95% CI] = 0.97 [0.60 to 1.56]). Other outcomes were also similar between groups.

CONCLUSION

Using this large national data set, we did not identify a difference in postinduction hypoxemia between ramped and supine positions in this cohort of ED intubations with apneic oxygenation.