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Context: Perioperative management of morbidly obese patients undergoing bariatric surgery is challenging. Lacking standardized perioperative protocols, complication rates may be high. This retrospective study aims to quantify the incidence of significant blood pressure decreases on induction of anesthesia and intraoperative hypoxemia, before implementation of a standardized protocol designed for bariatric surgery.

Design: Retrospective, observational study.

Setting: A 250-bed county hospital in northern Sweden.

Subjects: 219 morbidly obese patients (body mass index > 35 kg/m²) who underwent bariatric surgery between 2003 and 2008.

Main outcome measures: Incidence of systolic blood pressure (SAP) falls to less than 70% of the preoperative baseline during induction of anesthesia and incidence of perioperative hypoxemia.

Results: The incidence of confirmed SAP falls to below 70% of baseline at induction of anesthesia was 56.2% (n = 123/219). This incidence rose with increasing age (p < 0.001) but not with body mass index (BMI). 3.7% (n = 8/219) of cases were marked as difficult intubations. A transient period of hypoxemia was observed in 6.8% (n = 15/219) and was more common with increasing BMI (p = 0.005). Fourteen different drug combinations were used in the study population. Of those administered an induction anesthetic drug, 72.6% (n = 159/193) were given an overdose when calculated by lean body weight, but this did not correlate significantly to SAP falls (p = 0.468).

Conclusions: The incidence of a significant blood pressure fall upon induction of anesthesia was common. The incidence of airway and ventilation problems were low. Overdosing of anesthetics and excessive variation in applied anesthesia methods were found.

Background: Preoperative anxiety in pediatric patients can worsen postoperative outcomes and delay discharge. Drugs aimed at reducing preoperative anxiety and facilitating postoperative recovery are available; however, their effects on postoperative recovery from propofol-remifentanil anesthesia have not been studied in preschool-aged children. Thus, we aimed to investigate the effects of three sedative premedications on postoperative recovery from total intravenous anesthesia in children aged 2–6 years.

Methods: In this prespecified secondary analysis of a double-blinded randomized trial, 90 children scheduled for ear, nose, and throat surgery were randomized (1:1:1) to receive sedative premedication: oral midazolam 0.5 mg/kg, oral clonidine 4 μg/kg, or intranasal dexmedetomidine 2 μg/kg. Using validated instruments, outcome measures including time for readiness to discharge from the postoperative care unit, postoperative sedation, emergence delirium, anxiety, pain, and nausea/vomiting were measured.

Results: After excluding eight children due to drug refusal or deviation from the protocol, 82 children were included in this study. No differences were found between the groups in terms of median time [interquartile range] to readiness for discharge (midazolam, 90 min [48]; clonidine, 80 min [46]; dexmedetomidine 100.5 min [42]). Compared to the midazolam group, logistic regression with a mixed model and repeated measures approach found no differences in sedation, less emergence delirium, and less pain in the dexmedetomidine group, and less anxiety in both clonidine and dexmedetomidine groups.

Conclusions: No statistical difference was observed in the postoperative recovery times between the premedication regimens. Compared with midazolam, dexmedetomidine was favorable in reducing both emergence delirium and pain in the postoperative care unit, and both clonidine and dexmedetomidine reduced anxiety in the postoperative care unit. Our results indicated that premedication with α₂-agonists had a better recovery profile than short-acting benzodiazepines; although the overall recovery time in the postoperative care unit was not affected.

Purpose: Sedative premedication in children may negatively impact their cardiorespiratory status during the perioperative course, and no clear consensus exists on the optimal premedication treatment for pediatric patients. The objective was to compare the perioperative cardiorespiratory responses to sedation using three different sedative premedication regimens in preschool children scheduled for surgery with total intravenous anesthesia.

Design: A single-center randomized controlled trial.

Methods: This is a planned secondary analysis of a study conducted at a 200-bed tertiary referral hospital. Ninety children participated in the study. They were aged 2–6 years and scheduled for ear, nose, and throat surgery with propofol/remifentanil anesthesia. Participants were randomly assigned to receive oral midazolam 0.5 mg/kg-1 (MID), oral clonidine 4 mcg/kg–1 (CLO), or intranasal dexmedetomidine 2 mcg/kg-1 (DEX). The main outcome measures were the sedation level, based on the Ramsay Sedation Scale (RSS), and cardiorespiratory status, monitored during the perioperative period.

Findings: The final cohort had 83 children (MID, n=27; CLO, n=26; DEX, n=30), with similar intergroup patient characteristics. RSS scores were lower in the MID group than in the CLO and DEX groups before induction and within 30 min postsurgery (P<0.001 and P=0.006, respectively). A negative correlation existed between the RSS and heart rate (HR) (r=-0.570, P<0.001). Before anesthesia induction, the respiratory rate was lowest in the DEX group (MID 21.5±1.7 min–1, CLO 20.6±2.6 min–1, DEX 20.2±1.7 min–1; P=0.042). The HR was lower in the CLO and DEX groups than in the MID group (MID, 102.8±10.0 min–1; CLO, 87.4±9.6 min–1; DEX, 87.6±7.9 min–1; P<0.001). The HR was lower immediately after induction (P=0.009) and intraoperatively (P=0.025) in the CLO and DEX groups than in the MID group.

Conclusions: When used as premedication before propofol/remifentanil anesthesia, clonidine and dexmedetomidine provided deeper preoperative sedation compared to midazolam. From a clinical perspective, all three study drugs provided essentially stable cardiovascular and respiratory conditions during the entire perioperative period.

Purpose: Providing perioperative care for children who express anxiety or react with negative anxiety-associated consequences can be a challenge. The use of premedication is established as an important intervention for young children before surgery, yet research into care providers’ experiences of premedication is limited. The aim of this study was to explore perioperative staff’s experiences of premedication for preschool-age children.

Design: A descriptive inductive qualitative study was performed based on focus group discussions.

Methods: A purposive sample of a team from the operating department with experience in anesthetizing and caring for children in the perioperative period was interviewed in small focus groups: five preoperative and postoperative care nurses, five nurse anesthetists, and five anesthesiologists. The transcribed text was categorized using qualitative content analysis.

Findings: The content analysis revealed three themes: a matter of time, do not wake the sleeping bear, and on responsive tiptoes.

Conclusions: Care providers must adapt their work to the child’s emotional state of mind and needs, allowing time for the child to trust and accept the premedication and for the premedication to reach its peak effect. Premedication provides light sleep preoperatively, which requires careful treatment of the child to avoid emotional reactions, and the postoperative path is most peaceful when the premedication supports a long duration of sedation. Our findings highlight the need for safety precautions and a permissive and flexible organization with the goal of achieving a smooth and safe journey for the child in the perioperative path.

Introduction: Anxiety in pediatric patients may challenge perioperative anesthesiology management and worsen postoperative outcomes. Sedative drugs aimed to reducing anxiety are available with different pharmacologic profiles, and there is no consensus on their effect or the best option for preschool children. In this study, we aimed to compare the effect of three different premedications on anxiety before anesthesia induction in preschool children aged 2-6 years scheduled for elective surgery. The secondary outcomes comprised distress during peripheral catheter (PVC) insertion, compliance at anesthesia induction, and level of sedation.

Patients and methods: In this double-blinded randomized clinical trial, we enrolled 90 participants aged 2-6 years, who were scheduled for elective ear-, nose-and-throat surgery. The participants were randomly assigned to three groups: those who were administered 0.5 mg/kg oral midazolam, 4 µg/kg oral clonidine, or 2 µg/kg intranasal dexmedetomidine. Anxiety, distress during PVC insertion, compliance with mask during preoxygenation, and sedation were measured using the modified Yale Preoperative Anxiety Scale, Behavioral Distress Scale, Induction Compliance Checklist, and Ramsay Sedation Scale, respectively.

Results: Six children who refused premedication were excluded, leaving 84 enrolled patients. At baseline, all groups had similar levels of preoperative anxiety and distress. During anesthesia preparation, anxiety was increased in the children who received clonidine and dexmedetomidine; however, it remained unaltered in the midazolam group. There were no differences in distress during PVC insertion or compliance at induction between the groups. The children in the clonidine and dexmedetomidine groups developed higher levels of sedation than those in the midazolam group.

Conclusions: In preschool children, midazolam resulted in a more effective anxiolysis and less sedation compared to clonidine and dexmedetomidine.

Background: Intrathoracic pressure related to breathing or positive pressure ventilatory support has effects on venous return to the heart and transmyocardial pressures. In addition, autonomic nerve system activity affects cardiac inotropy, chronotropy, and loading. Knowledge of these physiological interactions is relevant when interpreting atrial and ventricular strain results as part of heart function assessment by echocardiography in patients with ventilatory support. 

Purpose: We aimed to assess 2-D global longitudinal strain (GLS%) for all four heart chambers (atria and ventricles) during controlled changes in intrathoracic pressure, as well as sympathetic nerve system activation. We hypothesized that GLS% is affected by both load and sympathetic tone. 

Methods: With ethical approval and participant consent, 20 healthy volunteers (medical students) performed a controlled Valsalva manoeuvre, a mask positive pressure inspiration (CPAP) manoeuvre (25 cm H2O) and a Hand Grip manoeuvre (squeezing a rolled towel with 75% of maximum force with one hand for 2 minutes). We monitored continuous blood pressure and heart rate (using a Finapres) during the manoeuvres to make sure that the manoeuvres caused the desired physiologic effects.

GLS% of the individual chambers were measured before and during these manoeuvres using commercially available post- processing software, from the 4-chamber view. 2 different operators measured independently the GLS% for every manoeuvre.  Paired measurement comparisons were performed (paired t test). 

Results: Both the Valsalva maneuverer and CPAP caused reductions in GLS % in all four chambers. The Hand Grip manoeuvre did not cause any change in GLS % in any chamber.

Conclusion: Since both CPAP and late Valsalva causes a reduction in preload, we assume that a decrease in preload causes a reduction in GLS% in the heart chambers. Both Valsalva and Handgrip manoeuvres causes a raised sympathicus tone which does not seem to affect GLS% in any chamber. (In the Hand Grip manoeuvre there was a rise in blood pressure and pulse during the manoeuvre, as a sign of increased sympathetic tone.)

From these preliminary findings, we conclude that for healthy young individuals GLS% appears to decrease in all chambers during Valsalva and CPAP, while no change in GLS% is caused by the Hand Grip manoeuvre.

BACKGROUND: In order to assess left atrial contractile function in disturbed circulatory conditions, it is necessary to have a clear understanding of how it behaves in a normal resting state with changes in loading conditions. However, currently the understanding of this relationship is incomplete. We hypothesize that in healthy individuals, left atrial contraction strain and its peak strain rate are increased or decreased by increasing or decreasing preload, respectively.

METHODS: Controlled maneuvers used to change preload included continuous positive airway pressure by mask (CPAP 20 cmH₂O) for preload decrease, and passive leg raise (15 degrees angle) for preload increase. Cardiac ultrasound 4-chamber views of the left atria and left ventricle were acquired at baseline and during maneuver. Acquired images were post processed and analyzed offline. Comparisons were made using paired t-test and means with 95% confidence interval.

RESULTS: There were 38 participants, complete results were obtained from 23 in the CPAP maneuver and 27 in the passive leg raise maneuver. For the CPAP group, left atrial contraction strain was 11.6% (10.1 to 13.1) at baseline and 12.8% (11.0 to 14.6) during the maneuver (p = 0.16). Left atrial contraction peak strain rate was - 1.7 s^- 1 (- 1.8 to - 1.5) at baseline and - 1.8 s^- 1 (- 2.0 to - 1.6) during the maneuver (p = 0.29). For the passive leg raise-group, left atrial contraction strain was 10.1% (9.0 to 11.2) at baseline and 10.8% (9.4 to 12.3) during the maneuver (p = 0.28). Left atrial contraction peak strain rate was - 1.5 s^- 1 (- 1.6 to - 1.4) at baseline and - 1.6 s^- 1 (- 1.8 to - 1.5) during the maneuver (p = 0.29). Left atrial area, an indicator of preload, increased significantly during passive leg raise and decreased during CPAP.

CONCLUSION: In healthy individuals, left atrial contraction strain and its peak strain rate seem to be preload-independent.

TRIAL REGISTRATION: The study was 2018-02-19 registered at clinicaltrials.gov ( NCT03436030 ).

BACKGROUND: Cardiac mechanics are influenced by loading conditions as well as sympathetic tone. Left atrial (LA) contractile function assessed by two-dimensional (2D) strain has been described in the setting of controlled preload alterations; however, studies show conflicting findings about change or direction of change. We hypothesized that the controlled preload reduction and the sympathetic nervous system activation that occurs during a standardized Valsalva manoeuvre would bring about a change in LA contraction strain.a

METHODS: Healthy young adults of both sexes were recruited. Transthoracic echocardiographic ultrasound images were collected before and during a Valsalva manoeuvre. Standard imaging windows for LA strain assessment were used and the images were copied and stored for later offline analysis. These were assessed for adequate atrial wall visualization in 2D strain assessment. Paired comparisons were carried out using Student's T test.

RESULT: Thirty-eight participants were included and there were 22 complete studies with paired pre- and during Valsalva manoeuvre. LA contraction strain at baseline was 10.5 ± 2.8% (standard deviation) and during the Valsalva manoeuvre 10.6 ± 4.6%, p = 0.86.

CONCLUSION: The Valsalva manoeuvre, a combination of preload reduction and sympathetic nervous system activation, seems not to be associated with a change in LA contraction strain in healthy young individuals. LA contraction strain should be interpreted in the context of both atrial loading conditions and prevailing autonomic nervous system activity.

Background: The overall risk of post-operative nausea and vomiting (PONV) after general anaesthesia is reportedly 20%–40%. The first episode of PONV may occur early in the post-anaesthesia care unit (PACU) or later at the ward or after discharge at home in an ambulatory setting. This study aimed to investigate and describe the risk of early PONV in a PACU, and we hypothesised that patients and perioperative factors were associated with early PONV.

Methods: This single-centre retrospective observational study was conducted in a Swedish county hospital from January to June 2017 and included adult patients who underwent surgical procedures under general anaesthesia. Perioperative data were obtained by reviewing the local registry for surgical procedures, medical records and anaesthesia and post-operative charts. Early PONV was defined as PONV occurring up to 4 hours post-operatively at the PACU. Any notification in the medical records, perioperative charts or the registry regarding nausea, vomiting or PONV treatment was regarded as PONV. Univariate and multivariate analyses were performed for factors associated with early PONV.

Results: A total of 2030 patients were included in the study, of which 9.6% (n = 194) experienced early PONV. Factors associated with a high risk of early PONV were suboptimal PONV prophylaxis, need for opioids, female sex, body mass index >35 kg m−2 and major surgery and anaesthesia time ≥60 minutes.

Conclusion: We found that every 10th patient under general anaesthesia experienced early PONV. Suboptimal PONV prophylaxis and previously acknowledged risk factors for PONV were associated with early PONV.

BACKGROUND: Approximately 25% of ambulatory surgery patients experience post-discharge nausea and vomiting (PDNV). We aimed to investigate whether palonosetron, a long-acting anti-emetic, decreases the incidence of PDNV in high-risk patients.

METHODS: In this prospective, randomised, double-blind, placebo-controlled trial, 170 male and female patients undergoing ambulatory surgery under general anaesthesia, with a high predicted risk for PDNV, were randomised to receive either palonosetron 75 μg i.v. (n=84) or normal saline (n=86) before discharge. During the first 3 postoperative days (PODs), we measured outcomes using a patient questionanaire. The primary outcome was the incidence of a complete response (no nausea, vomiting, or use of rescue medication) until POD 2. Secondary outcomes included the incidence of PDNV each day until POD 3.

RESULTS: The incidence of a complete response until POD 2 was 48% (n=32) in the palonosetron group and 36% (n=25) in the placebo group (odds ratio 1.69 [95% confidence interval: 0.85-3.37]; P=0.131). No significant difference in the incidence of PDNV was observed between the two groups on the day of surgery (47% vs 56%; P=0.31). Significant differences in the incidence of PDNV were found on POD 1 (18% vs 34%; P=0.033) and POD 2 (9% vs 27%; P=0.007). No differences were observed on POD 3 (15% vs 13%; P=0.700).

CONCLUSIONS: Compared with placebo, palonosetron did not reduce the overall incidence of PDNV up to POD 2. The lower incidence of PDNV on POD 1 and POD 2 in the palonosetron group requires further investigation.

BACKGROUND: Restrictive lung function may indicate various underlying diseases. The aim of this study was to evaluate the accuracy of different restrictive spirometry patterns (RSPs) to identify restrictive lung function (total lung capacity [TLC] < lower limit of normal [LLN]) according to reference values by the Global Lung Function Initiative (GLI) in a wide age-ranged, general population sample.

METHODS: A general population sample (n = 607, age 23-72 years, smokers 18.8%) with proper dynamic spirometry and TLC measurements, was included. Accuracy of two main categories of RSP to identify TLC < LLN were evaluated: traditional RSPs (definition 1: FVC < 80% of predicted and FEV₁ /FVC ≥ 0.7 and definition 2: FVC < LLN and FEV₁ /FVC ≥ LLN) and RSPs defined by Youden's method (definition 3: FVC < 85.5% of predicted and FEV₁ /FVC ≥ LLN and definition 4: FVC Z-score < -1.0 and FEV₁ /FVC ≥ LLN).

RESULTS: The prevalence of restrictive lung function (TLC < LLN) was 5.3%. The most accurate cut-offs for FVC to identify TLC < LLN were 85.5% for FVC% of predicted, and -1.0 for FVC Z-score. The traditional RSP definitions 1 and 2 had higher specificity (95.0% and 96.9%) but substantially lower sensitivity compared to RSP definitions 3 and 4.

CONCLUSION: Based on the GLI reference values, the RSP definition FVC < LLN and FEV₁ /FVC ≥ LLN yielded the highest specificity and may appropriately be used to rule out restrictive lung function. The RSP definition with the most favourable trade-off between sensitivity and specificity, FVC < 85.5% of predicted and FEV₁ /FVC ≥ LLN, may serve as an alternative with higher sensitivity for screening.

BACKGROUND: Preserving perfusion pressure during anesthesia induction is crucial. Standardized anesthesia methods, alert fluid therapy and vasoactive drugs may help maintain adequate hemodynamic conditions throughout the induction procedure. In this randomized study, we hypothesized that a pre-operative volume bolus based on lean body weight would decrease the incidence of significant blood pressure drops (BPD) after induction with target-controlled infusion (TCI) or rapid sequence induction (RSI).

METHODS: Eighty individuals scheduled for non-cardiac surgery were randomized to either a pre-operative colloid fluid bolus of 6 ml kg^-1 lean body weight or no bolus, and then anesthetized by means of TCI or RSI. The main outcome measure was blood pressure drops below the mean arterial pressure 65 mm Hg during the first 20 minutes after anesthesia induction. ClinicalTrials.com Identifier: NCT03394833.

RESULTS: Pre-operative fluid therapy decreased the incidence of BPDs fivefold, from 23 of 40 (57.5%) individuals without fluids to 5 of 40 (12.5%) with fluid management, P < .001. The mean BPD was greater in the groups without pre-operative fluids compared to the groups with fluid management; 53 ± 18 mm Hg vs 43 ± 14 mm Hg, P = .007. The overall mean volume of pre-operative fluid bolus infused was 387 ± 52 ml. There was no difference in hemodynamic stability between TCI and RSI. No correlation was shown between incidence of BPDs and increasing age, medication, hypertension, diabetes, renal failure, or low physical capacity.

CONCLUSIONS: Pre-operative fluid bolus decreased the incidence of significant blood pressure drops during TCI and RSI induction of general anesthesia.

Background: In morbidly obese individuals (MO) cardiorespiratory comorbidities and body habitus challenge the perioperative management of anesthesia. To implement safe and reproducible routines for anesthesia and fluid therapy is the cornerstone in order to minimize anesthesia-related complications and to meet individual variability in rehydration needs.

Methods: Paper I: Impact of rapid-weight-loss preparation prior to bariatric surgery was investigated. Prevalence of preoperative dehydration and cardiac function were assessed with transthoracic echocardiography (TTE). Paper II: The anesthetic technique for rapid sequence induction (RSI) in MO based on a combination of volatile and i.v. anesthetics was developed. Pre- and post-induction oxygenation, blood pressure levels and feasibility of the method was evaluated. Paper III: The preoperative ideal body weight based rehydration regime was evaluated by TTE. Paper IV: Need of rehydration during bariatric surgery was evaluated by comparing conventional monitoring to a more advanced approach (i.e. preoperative TTE and arterial pulse wave analysis).

Results: Rapid-weight-loss preparation prior to bariatric surgery may expose MO to dehydration. TTE was shown to be a robust modality for preoperative screening of the level of venous return, assessment of filling pressures and biventricular function of the heart in MO. The combination of sevoflurane, propofol, alfentanil and suxamethonium was demonstrated to be a safe method for RSI regardless of BMI. The preoperative rehydration regime implemented by colloids 6 ml/kg IBW was an adequate treatment to obtain euvolemia. In addition, preoperative rehydration seems to increase hemodynamic stability during intravenous induction of anesthesia and even intraoperatively.

Conclusion: This thesis describes a safe and comprehensive perioperative management of morbidly obese individuals scheduled for bariatric surgery. Hemodynamic and respiratory stability can be achieved by implementation of strict and proven methods of anesthesia and fluid therapy. Much focus should be placed on feasible monitoring and preoperative optimization in morbidly obese individuals for increased perioperative safety.

BACKGROUND: Preoperative venous return (VR) optimization and adequate blood volume is essential in management of morbidly obese patients (MO) in order to avoid perioperative circulatory instability. In this study, all subjects underwent a preoperative 3-week preparation by rapid-weight-loss-diet (RWL) as part of their treatment program for bariatric surgery.

METHODS: This is a prospective, observational study of 34 morbidly obese patients consecutively scheduled for bariatric surgery at Sunderby County Hospital, Lulea, Sweden. Preoperative transthoracic echocardiography (TTE) was performed in the awake state before and after intravascular volume challenge (VC) of 6 ml colloids/kg ideal body weight (IBW). Effects of standardized VC were evaluated by TTE. Dynamic and non-dynamic echocardiographic indices for VC were studied. Volume responsiveness and level of VR before and after VC were assessed by TTE. An increase of stroke volume >/=13 % was considered as a volume responder.

RESULTS: Twenty-nine out of 34 patients were volume responders. After VC, a majority of patients (23/34) were euvolemic, and only 2/34 were hypovolemic. Post-VC hypervolemia was observed in 9/34 of patients.

CONCLUSIONS: The IBW-based volume challenge regime was found to be suitable for preoperative rehydration of RWL-prepared MO. Most of the patients were volume responders. Preoperative state of VR was not associated with volume responsiveness. IBW estimates and appropriate monitoring avoids potential hyperhydration in MO. For VC assessment, conventional Doppler indices were found to be more suitable compared to tissue Doppler, giving sufficient information on pressure-volume correlation of the left ventricle in morbidly obese.

BACKGROUND: In morbidly obese patients (MO), adequate levels of venous return (VR) and left ventricular filling pressures (LVFP) are crucial in order to augment perioperative safety. Rapid weight loss (RWL) preparation with very low calorie diet is commonly used aiming to facilitate bariatric surgery. However, the impact of RWL on VR and LVFP is poorly studied.

METHODS: In this prospective, controlled, single-center study, we hypothesized that RWL-prepared MO prior to bariatric surgery can be hypovolemic (i.e., low VR) and compared MO to lean controls with conventional overnight fasting. Twenty-eight morbidly obese patients were scheduled consecutively for bariatric surgery and 19 lean individuals (control group, CG) for elective general surgery. Preoperative assessment of VR, LVFP, and biventricular heart function was performed by a transthoracic echocardiography (TTE) protocol to all patients in the awake state. Assessment of VR and LVFP was made by inferior vena cava maximal diameter (IVCmax) and inferior vena cava collapsibility index- (IVCCI) derived right atrial pressure estimations.

RESULTS: A majority of MO (71.4 %) were hypovolemic vs. 15.8 % of lean controls (p < 0.001, odds ratio = 13.3). IVCmax was shorter in MO than in CG (p < 0.001). IVCCI was higher in MO (62.1 +/- 23 %) vs. controls (42.6 +/- 20.8; p < 0.001). Even left atrium anterior-posterior diameter was shorter in MO compared to CG.

CONCLUSIONS: Preoperative RWL may induce hypovolemia in morbidly obese patients. Hypovolemia in MO was more common vs. lean controls. TTE is a rapid and feasible tool for assessment of preload even in morbid obesity.

Background and objective: The interest in bariatric surgery is growing. Morbidly obese patients have an increased risk of hypoxia and decreased blood pressure during rapid sequence induction (RSI). Alternate RSI methods that provide cardiovascular and respiratory stability are required. With this in mind, we evaluated a method for volatile RSI in morbidly obese patients.

Design: Observational study.

Methods: Thirty-four patients with mean BMI 42.4 kg m(-2) undergoing bariatric surgery (morbidly obese group) and 22 patients with mean BMI 25.6 kg m(-2) as a control group were included in the study. Anaesthesia was induced with sevoflurane, propofol, suxamethonium and alfentanil, designed to avoid respiratory and haemodynamic adverse events and to minimise depressing effect on the brain respiratory centre under ongoing RSI. Peripheral oxygen saturation (SpO(2)) and mean arterial blood pressure were registered before and after endotracheal intubation. In addition, two time periods were measured during RSI: spontaneous breathing time (SBT) and apnoea time.

Results: We found no significant differences between the groups. No periods of desaturation were detected. SpO(2) was 100% before and after endotracheal intubation in all patients. Mean arterial pressure was maintained at a stable level in both groups. Mean SBT and apnoea time were 65.6 and 45.8 s in the morbidly obese group, and 70.7 and 47.7 s in the control group, respectively.

Conclusion: A combination of sevoflurane, propofol, suxamethonium and alfentanil is a suitable method for RSI which maintains cardiovascular and respiratory stability in both morbidly obese and lean patients.

Background

In bariatric surgery, non-or mini-invasive modalities for cardiovascular monitoring are addressed to meet individual variability in hydration needs. The aim of the study was to compare conventional monitoring to an individualized goal-directed therapy (IGDT) regarding the need of perioperative fluids and cardiovascular stability. 

Methods

Fifty morbidly obese patients were consecutively scheduled for laparoscopic bariatric surgery (ClinicalTrials.gov Identifier: NCT01873183). The intervention group (IG, n=30) was investigated preoperatively with transthoracic echocardiography (TTE) and rehydrated with colloid fluids if a low level of venous return was detected. During surgery, IGDT was continued with a pulse-contour device (FloTrac (TM)). In the control group (CG, n=20), conventional monitoring was conducted. The type and amount of perioperative fluids infused, vasoactive/inotropic drugs administered, and blood pressure levels were registered. 

Results

In the IG, 213 +/- 204 mL colloid fluids were administered as preoperative rehydration vs. no preoperative fluids in the CG (p<0.001). During surgery, there was no difference in the fluids administered between the groups. Mean arterial blood pressures were higher in the IG vs. the CG both after induction of anesthesia and during surgery (p=0.001 and p=0.001). 

Conclusions

In morbidly obese patients suspected of being hypovolemic, increased cardiovascular stability may be reached by preoperative rehydration. The management of rehydration should be individualized. Additional invasive monitoring does not appear to have any effect on outcomes in obesity surgery.

BACKGROUND: Cardiac disease and aberrations in central volume statusare risk factors for perioperative complications,and should be identified prior to surgery. This study investigatedthe benefit of transthoracic echocardiography for preoperative identification of cardiac disease andhypovolemia in ambulatory surgery.

METHODS: Ninety-six patients, with a mean age of 63.5±12.2 years and body mass index of 27.0±4.3 kg/m² , scheduled for ambulatorysurgery (breast, thyroid, minor gastrointestinal), were consecutively enrolled in this prospective observational study. Preoperative comprehensive transthoracic echocardiographywas performed in order to assess heart failure, asymptomatic left ventricular dysfunction, valvular disease and aberrations incentral volume status.

RESULTS: Preoperative transthoracic echocardiography identified a total of 28 cases of heart failure; thirteen cases of heart failure with reduced, or moderately reduced, ejection fraction and fifteen cases of heart failure with preserved ejection fraction. Furthermore, forty-six cases of asymptomatic left ventricular dysfunction were identified. 44/96 patients were hypovolemic, 16 of whom in severe hypovolemia.Seven cases of previously unknown obstructive valvular or myocardial diseaseand six cases of right ventricular systolic dysfunction were identified.A total of 24% (23/96) were classified as potential critical hemodynamic findings. The number needed to treat for preoperative TTE in order to find one critical finding was 4.2.

CONCLUSION: In this ambulatory surgical cohort, a high prevalence of preoperative LV dysfunction and aberrations in volume status was observed. The results demonstrate that preoperative TTE contributed valuable hemodynamic information. The standard preoperative assessment for this cohort might need to be revised.

Background: Left ventricular (LV) diastolic dysfunction is an acknowledged peri-operative risk factor that should be identified before surgery. This study aimed to evaluate a simplified echocardiographic method using e’ and E/e’ for identification and grading of diastolic dysfunction pre-operatively.

Methods: Ninety six ambulatory surgical patients were consecutively included to this prospective observational study. Pre-operative transthoracic echocardiography was conducted prior to surgery, and diagnosis of LV diastolic dysfunction was established by comprehensive and simplified assessment, and the results were compared. The accuracy of e’-velocities in order to discriminate patients with diastolic dysfunction was established by calculating accuracy, efficiency, positive (PPV) and negative predictive (NPV) values, and area under the receiver operating characteristic curve (AUROC).

Results: Comprehensive assessment established diastolic dysfunction in 77% (74/96) of patients. Of these, 22/74 was categorized as mild dysfunction, 43/74 as moderate dysfunction and 9/74 as severe dysfunction. Using the simplified method with e’ and E/e’, diastolic dysfunction was established in 70.8% (68/96) of patients. Of these, 8/68 was categorized as mild dysfunction, 36/68 as moderate dysfunction and 24/68 as severe dysfunction. To discriminate diastolic dysfunction of any grade, e’-velocities (mean < 9 cm s− 1) had an AUROC of 0.901 (95%CI 0.840–0.962), with a PPV of 55.2%, a NPV of 90.9% and a test efficiency of 0.78.

Conclusions: The results of this study indicate that a simplified approach with tissue Doppler e’-velocities may be used to rule out patients with diastolic dysfunction pre-operatively, but together with E/e’ ratio the severity of diastolic dysfunction may be overestimated.

BACKGROUND: Left ventricular (LV) systolic dysfunction is an acknowledged perioperative risk factor and should be identified before surgery. Conventional echocardiographic assessment of LV ejection fraction (LVEF) obtained by biplane LV volumes is the gold standard to detect LV systolic dysfunction. However, this modality needs extensive training and is time consuming. Hence, a feasible point-of-care screening method for this purpose is warranted. The aim of this study was to evaluate 3 point-of-care echocardiographic methods for identification of LV systolic dysfunction in comparison with biplane LVEF.

METHODS: One hundred elective surgical patients, with a mean age of 63 ± 12 years and body mass index of 27 ± 4 kg/m, were consecutively enrolled in this prospective observational study. Transthoracic echocardiography was conducted 1-2 hours before surgery. LVEF was obtained by automatic two-dimensional (2D) biplane ejection fraction (EF) software. We evaluated if Tissue Doppler Imaging peak systolic myocardial velocities (TDISm), anatomic M-mode E-point septal separation (EPSS), and conventional M-mode mitral annular plane systolic excursion (MAPSE) could discriminate LV systolic dysfunction (LVEF <50%) by calculating accuracy, efficiency, correlation, positive (PPV) respective negative predictive (NPV) values, and area under the receiver operating characteristic curve (AUROC) for each point-of-care method.

RESULTS: LVEF<50% was identified in 22% (21 of 94) of patients. To discriminate an LVEF <50%, AUROC for TDISm (mean <8 cm/s) was 0.73 (95% confidence interval [CI], 0.62-0.84; P < .001), with a PPV of 47% and an NPV of 90%. EPSS with a cutoff value of >6 mm had an AUROC 0.89 (95% CI, 0.80-0.98; P < .001), with a PPV of 67% and an NPV of 96%. MAPSE (mean <12 mm) had an AUROC 0.80 (95% CI, 0.70-0.90; P < 0.001) with a PPV of 57% and an NPV of 98%.

CONCLUSIONS: All 3 point-of-care methods performed reasonably well to discriminate patients with LVEF <50%. The clinician may choose the most suitable method according to praxis and observer experience.

Background: Adult-onset asthma is associated with a poor treatment response. The aim was to study associations between clinical characteristics, asthma control and treatment in adult-onset asthma.

Methods: Previous participants within the population-based Obstructive Lung Disease in Northern Sweden studies (OLIN) were in 2019–2020 invited to clinical examinations including structured interviews, spirometry, fractional exhaled nitric oxide (FeNO), skin prick test and blood sampling. In total, n = 251 individuals with adult-onset asthma (debut >15 years of age) were identified. Uncontrolled asthma was defined according to ERS/ATS and treatment step according to GINA (2019).

Results: Among individuals with uncontrolled asthma (34%), severe obesity (16.3% vs 7.9%, p = 0.041) and elevated levels of blood neutrophils, both regarding mean level of blood neutrophils (4.25*109/L vs 3.67*109/L, p = 0.003), and proportions with ≥4*109/L (49.4% vs 33.3%, p = 0.017) and ≥5*109/L (32.1% vs 13.7%, p < 0.001) were more common than among those with controlled asthma. Adding the dimension of GINA treatment step 1–5, individuals with uncontrolled asthma on step 4–5 treatment had the highest proportions of blood neutrophils ≥5*109/L (45.5%), severe obesity (BMI≥35, 26.1%), dyspnea (mMRC≥2) (34.8%), and most impaired lung function in terms of FEV1%<80% of predicted (42.9%), FEV1<LLN (47.6%), FVC<80% of predicted (42.9%) and FVC < LLN (38.1%). No associations between level of asthma control and treatment were found regarding blood eosinophils, FeNO or allergic sensitization.

Conclusion: This study indicates that in adult-onset asthma, primarily non-type-2 characteristics such as obesity and blood neutrophils associate with poor asthma control and higher doses of inhaled corticosteroids.

Background: Deterioration after ICU discharge may lead to readmission or even death. Interventions (e.g. critical care transition programs) have been developed to improve the clinical handover between the ICU and ward. We conducted a systematic review with meta‐analysis and trial sequential analysis (TSA) according to Cochrane Handbook and Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology to assessthe impact of these interventions on readmission and death (PROSPERO, no CRD42019121746).

Methods: We searched PubMed/MEDLINE, CINAHL, AMED, PsycINFO and the Cochrane Central Register for Controlled Trials from inception until January 2019. We included historically controlled studies that evaluated critical care transition programs in adults discharged from the ICU. Readmission and in‐hospital mortality were the primary outcomes. Risk of bias, publications bias and the quality of evidence were assessed with the ROBINS‐I tool, funnel plot and GRADE, respectively.

Results: Fifteen observational studies were included (11 in meta‐analysis). All studies had at least serious risk of bias. ICU discharge within a critical care transition program modestly reduced the risk of readmission (RR 0.78; 95% CI: 0.64 to 0.96; TSA‐adjusted 95% CI: 0.59 to 1.03) but not in‐hospital mortality (RR 0.82; 95% CI: 0.64 to 1.06; TSA‐adjusted 95% CI: 0.49 to 1.37). There was substantial heterogeneity among studies. TSA indicated lack of firm evidence. The GRADE quality of evidence on outcomes was very low.

Conclusions: We found no clear benefit in terms of reducing risk of readmission or death after ICU discharge,however with overall very low certainty of evidence.