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Background: The reported incidence of postoperative nausea and vomiting (PONV) after laparoscopic bariatric surgery is up to 60–80%. Hower, studies are limited, and larger studies are warranted. As PONV is usually evaluated in the post-anesthesia care unit (PACU), studying early PONV can be a valuable tool for exploring risk and associated factors for PONV.

Methods: Using prospectively collected data from the Swedish perioperative registry (SPOR) from 2016 to 2022, we explore the incidence and associated factors for early PONV after laparoscopic bariatric surgery. Laparoscopic gastric bypass and laparoscopic gastric sleeve procedures in adult patients (≥ 18 years) were included. The primary outcome was the incidence of PONV in the PACU. Secondary outcomes were factors associated with PONV, which were analyzed using a multivariate logistic regression model.

Results: In total, 14,098 procedures were identified in the registry during the study period, and 8426 unique patients from 32 hospitals in Sweden were included in the final study cohort. PONV in PACU was present in 36% (n = 3018) of patients. Factors associated with early PONV were female sex, age, moderate-severe pain, gastric sleeve procedures, duration in PACU, and hospital.

Conclusions: In this national register-based cohort study, one third of patients experienced early PONV in the PACU after laparoscopic bariatric surgery. Several risk factors were associated with increased occurrence of PONV, and there was variability among hospitals in the incidence of PONV.

Clinicaltrials.gov: NCT04433676

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.

Background: COPD is largely underdiagnosed. Active identification of cases is crucial to establish preventive measures before manifestation of clinical disease. The significance of different spirometric patterns preceding COPD, especially preserved ratio impaired spirometry (PRISm), has been highlighted but remains unclear.

Research Question: Which clinical characteristics, smoking habits, and spirometric patterns, with primary focus on PRISm findings, precede the development of airway obstruction (AO)?

Study Design and Methods: The OLIN COPD Study was established from 2002 through 2004. After re-examination of population-based cohorts, individuals with AO (n = 993; FEV1 to VC ratio < 0.70) were identified together with control participants without AO (n = 993; FEV1 to VC ratio ≥ 0.70). Most of these people had participated in examinations during the 1980s or 1990s, and in total, 902 cases and 819 control participants had previous clinical data. Logistic regression was performed with case status as outcome and spirometric patterns, age, sex, smoking habits, and BMI at first examination as covariates.

Results: The mean (SD) person-years between first examination and inclusion in the OLIN COPD Study was 10.5 (4.0) years. At first examination, the prevalence of PRISm was higher in cases (18.6%) vs control participants (13.4%). Current smoking was more common in cases (45.1% vs 18.2%), whereas former smoking was similar (31.8% vs 34.9%). Cases reported more respiratory symptoms (78.0% vs 44.3%) than control participants. At first examination, PRISm, current smoking, and former smoking were strongly associated with becoming a case when adjusted for confounders, with adjusted OR (aOR) of 3.5, 4.1, and 1.5, respectively. When stratifying for smoking habits, aORs for PRISm in those with current smoking, former smoking, and nonsmoking status were 2.9, 3.8 and 3.7, respectively.

Interpretation: In this study, PRISm was associated with transition into AO corresponding to COPD within 1 decade, independent of smoking habits and with similar strength of association among those who have never smoked, who formerly smoked, and who currently smoke.

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.

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: 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: 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.

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: 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: 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.