Prolonged duration of action of suxamethonium in pregnant and postpartum patients: A registry study.

BACKGROUND: Suxamethonium is hydrolysed by butyrylcholinesterase (BChE) and a low BChE activity can result in a prolonged duration of action of suxamethonium. The BChE activity is reduced during pregnancy and postpartum period by up to 33%. However, it can also be reduced by mutations in the BChE gene. In this study, we assessed BChE activity and mutations in the BChE gene in pregnant and postpartum patients with prolonged duration of action of suxamethonium. It was hypothesised that at least 30% of patients with a low BChE activity did not have a mutation in the BChE gene. METHODS: In this registry study we focused on pregnant and postpartum patients with a history of prolonged duration of action of suxamethonium referred to the Danish Cholinesterase Research Unit (DCRU) between March 2007 and January 2023. Primary outcome was the proportion of patients without a mutation among patients with a low BChE activity. Secondary outcomes were the proportion of patients with a low BChE activity and the proportion of patients with a mutation out of the total number of patients. RESULTS: A total of 40 patients were included and among patients with a low BChE activity, 6% (95% CI: 1%-21%) did not have a mutation. Out of the total number of included patients referred to the DCRU, 90% (95% CI: 76%-97%) had a mutation and 94% (95% CI: 80%-99%) had a low BChE activity. CONCLUSION: Among pregnant and postpartum patients with a history of prolonged duration of action of suxamethonium and a low BChE activity, 6% did not have a mutation in the BChE gene. Our findings suggest that during pregnancy and postpartum clinically relevant prolonged duration of action of suxamethonium rarely occurs in genotypically normal patients.

Cocaine versus xylometazoline to prevent epistaxis after nasotracheal intubation: A randomized trial.

BACKGROUND: Nasotracheal intubation is associated with a risk of epistaxis. Several drugs, including cocaine and xylometazoline may be used as decongestants prior to nasotracheal intubation to prevent this. We hypothesized that xylometazoline would prevent epistaxis more effectively than cocaine, demonstrated by a lower proportion of patients with bleeding after nasotracheal intubation. METHODS: We conducted a single-center, outcome assessor and analyst-blinded, clinical randomized controlled trial following approval from the local research ethics committee and the national medicine agency. Written informed consent was obtained from all patients. Patients scheduled for surgery under general anesthesia with nasotracheal intubation were randomized to receive either 2 mL 4% cocaine or 2 mL 0.05% xylometazoline prior to nasotracheal intubation. Immediately following intubation, epistaxis was evaluated by the blinded intubating anesthetist on a four-point scale. We measured heart rate and blood pressure the first 5 min after drug administration. Adverse events were followed up after 24 h. RESULTS: A total of 53 patients received cocaine and 49 patients received xylometazoline. Bleeding occurred in 32 patients receiving cocaine (60.4%) and in 34 patients receiving xylometazoline (69.4%) (p = .41, Fisher's exact test) with a difference of 9.0% (95% CI: -9.4% to 27%). There was no statistically significant difference between groups regarding the heart rate or blood pressure. No adverse cardiac events were recorded in either group. CONCLUSION: We found no statistically significant difference between cocaine and xylometazoline in preventing epistaxis after nasotracheal intubation, and the choice of vasoconstrictor should be based on other considerations, such as pricing, availability and medicolegal issues.

Detection of cocaine 24 h after administration before nasotracheal intubation.

BACKGROUND: Cocaine may be applied to decongest the nasal mucosa before nasotracheal intubation, but patients risk a criminal offence if cocaine is detected when patients drive a car shortly after surgery. We aimed to evaluate whether benzoylecgonine levels in saliva exceeded the cut-off point 24 h after administration in patients undergoing nasotracheal intubation and whether cocaine would be detectable above the Danish legal fixed limit in blood samples 1 and 24 h after surgery. METHODS: We conducted a prospective study following approval from the local research ethics committee and the national medicine agency. Written informed consent was obtained from all patients. We included patients scheduled for surgery under general anaesthesia with nasotracheal intubation. They received 80 mg cocaine as a nasal spray 5 min before induction and nasotracheal intubation. The primary outcome was a dichotomous assessment of benzoylecgonine levels in saliva samples measured 24 h after administration of nasal cocaine with a cut-off limit of 200 ng/mL. Secondary outcomes were dichotomous assessments of cocaine in whole blood samples measured 1 and 24 h after administration of nasal cocaine with a cut-off limit of 0.01 mg/kg. RESULTS: Overall, 70 patients had valid saliva samples and 75 had valid blood samples 24 h after cocaine administration. Benzoylecgonine in saliva was traceable above the cut-off in 9/70 patients (13%; CI95%: 6% to 23%), and cocaine in blood was detected above the cut-off in 2/75 patients (3%; CI95%: 0.3% to 9%). CONCLUSION: We found benzoylecgonine traceable in saliva in 13% of patients and cocaine traceable in blood in 3% of patients 24 h after administration of 80 mg nasal cocaine. Patients should be informed when receiving cocaine and advised not to drive for at least 24 h.

Onset time, duration of action, and intubating conditions after mivacurium in elderly and younger patients.

BACKGROUND: The neuromuscular blocking agent mivacurium can be used during anesthesia to facilitate tracheal intubation. Data on onset time, duration of action, and effect on intubating conditions in patients 80 years and older are however limited. We hypothesized that onset time and duration of action of mivacurium would be longer in elderly patients than in younger adults. METHODS: This prospective observational study included 35 elderly (≥80 years) and 35 younger (18-40 years) patients. Induction of anesthesia comprised fentanyl 1-3 µg kg-1 and propofol 1.5-2.5 mg kg-1 and propofol and remifentanil for maintenance. Acceleromyography was used for monitoring neuromuscular blockade. The primary outcome was onset time defined as time from injection of mivacurium 0.2 mg kg-1 to a train-of-four (TOF) count of zero. Other outcomes included duration of action (time to TOF ratio ≥0.9), intubating conditions using the Fuchs-Buder scale and the intubating difficulty scale (IDS), and occurrence of hoarseness and sore throat postoperatively. RESULTS: No difference was found in onset time comparing elderly with younger patients; 219 s (SD 45) versus 203 s (SD 74) (difference: 16 s (95% CI: -45 to 14), p = .30). Duration of action was significantly longer in elderly patients compared with younger patients; 52 min (SD 17) versus 30 min (SD 8) (difference: 22 min [95% CI: 15 to 28], p < .001). No difference was found in the proportion of excellent intubating conditions (Fuchs-Buder); 31/35 (89%) versus 26/35 (74%) (p = .12) or IDS score (p = .13). A larger proportion of younger patients reported sore throat 24 h postoperatively; 34% versus 0%, p = .0002. No difference was found in hoarseness. CONCLUSION: No difference in onset time of mivacurium 0.2 mg kg-1 was found comparing elderly and younger patients. However, elderly patients had significantly longer duration of action. No difference was found in intubating conditions.

Transcutaneous carbon dioxide monitoring during prolonged apnoea with high-flow nasal oxygen.

BACKGROUND: The duration of apnoeic oxygenation with high-flow nasal oxygen is limited by hypercapnia and acidosis and monitoring of arterial carbon dioxide level is therefore essential. We have performed a study in patients undergoing prolonged apnoeic oxygenation where we monitored the progressive hypercapnia with transcutaneous carbon dioxide. In this paper, we compared the transcutaneous carbon dioxide level with arterial carbon dioxide tension. METHODS: This is a secondary publication based on data from a study exploring the limits of apnoeic oxygenation. We compared transcutaneous carbon dioxide monitoring with arterial carbon dioxide tension using Bland-Altman analyses in anaesthetised and paralysed patients undergoing prolonged apnoeic oxygenation until a predefined limit of pH 7.15 or PCO2 of 12 kPa was reached. RESULTS: We included 35 patients with a median apnoea duration of 25 min. Mean pH was 7.14 and mean arterial carbon dioxide tension was 11.2 kPa at the termination of apnoeic oxygenation. Transcutaneous carbon dioxide monitoring initially slightly underestimated the arterial tension but at carbon dioxide levels above 10 kPa it overestimated the value. Bias ranged from -0.55 to 0.81 kPa with limits of agreement between -1.25 and 2.11 kPa. CONCLUSION: Transcutaneous carbon dioxide monitoring provided a clinically acceptable substitute for arterial blood gases but as hypercapnia developed to considerable levels, we observed overestimation at high carbon dioxide tensions in patients undergoing apnoeic oxygenation with high-flow nasal oxygen.

Intra-operative blood transfusion in elderly patients on antithrombotic therapy.

BACKGROUND: Many elderly patients are receiving antithrombotics, which may increase intra-operative blood loss. We aimed to assess whether chronic antithrombotic therapy was associated with intra-operative transfusion of packed red blood cells in patients at least 80 years of age undergoing elective procedures. METHODS: We performed a secondary analysis of the prospective, observational European multicentre study entitled POSE (peri-interventional outcome study in the elderly) including 9497 surgical patients aged 80 years and older in 177 centres from October 2017 to December 2018. In this secondary analysis we included POSE patients who underwent elective procedures and with available data on chronic antithrombotic therapy. The primary outcome was intra-operative transfusion of packed red blood cells and results were analysed using multiple logistic regression model. We adjusted for the following predetermined explanatory variables: Age, sex, body mass index, American Society of Anaesthesiologists Physical Status Classification System, baseline haemoglobin concentration, disseminated cancer, and type and severity of surgery. RESULTS: A total of 7174 patients were included of whom 4073 (56.8%) were on antithrombotic therapy. Among patients on antithrombotic therapy 191 (4.7%) received intra-operative blood transfusion compared with 98 (3.2%) of patients not on chronic antithrombotic therapy (crude odds ratio: 1.51, 95% CI 1.18-1.94). Following multiple logistic regression analysis, the adjusted odds ratio was 0.98; 0.73-1.32. We found that chronic antithrombotic therapy was associated with intra-operative transfusion of packed red blood cells in elderly patients undergoing elective procedures in an unadjusted analysis, but not in a multivariate adjusted model.

Tracheal intubating conditions in elderly patients when train-of-four count is zero after rocuronium 0.6 or 0.9 mg/kg. A secondary analysis.

PURPOSE: The neuromuscular blocking agent rocuronium can be administered to facilitate tracheal intubation. We hypothesized that rocuronium 0.9 mg/kg provided a larger proportion of patients with vocal cords in abducted position compared to rocuronium 0.6 mg/kg at train-of-four (TOF) 0. METHODS: This secondary analysis was based on 52 elderly surgical patients of which 36 patients received rocuronium 0.6 mg/kg and 16 patients received rocuronium 0.9 mg/kg. Neuromuscular block was monitored with acceleromyography with TOF stimulation at the ulnar nerve. The primary outcome was the proportion of patients with vocal cords in abducted position at TOF 0. Secondary outcomes were intubating conditions evaluated by the Fuchs-Buder scale, the Intubating Difficulty Score (IDS), onset time, and duration of action of rocuronium. RESULTS: At TOF 0, a significantly larger proportion of patients had vocal cords in abducted position in the rocuronium 0.9 mg/kg group (81%) compared with the rocuronium 0.6 mg/kg group (53%); difference (%) 28, 95% Cl 3-53, P = 0.05. Excellent intubating conditions (Fuchs-Buder) were more common in the rocuronium 0.9 mg/kg group (62.5%); difference (%) 32.5, 95% Cl 4-61), P = 0.03. No significant difference was found in IDS or onset time of rocuronium (difference 19 s, 95% Cl: -5-43). Duration of action was significantly longer (difference 29 min, 95% Cl: 10-47) in the 0.9 mg/kg group. CONCLUSION: The proportion of patients with vocal cords in abducted position was significantly larger after rocuronium 0.9 mg/kg compared to rocuronium 0.6 mg/kg at TOF 0 monitored at the ulnar nerve.

Hyperoxia and Antioxidants for Myocardial Injury in Noncardiac Surgery: A 2 × 2 Factorial, Blinded, Randomized Clinical Trial.

BACKGROUND: Hyperoxia and oxidative stress may be associated with increased risk of myocardial injury. The authors hypothesized that a perioperative inspiratory oxygen fraction of 0.80 versus 0.30 would increase the degree of myocardial injury within the first 3 days of surgery, and that an antioxidant intervention would reduce degree of myocardial injury versus placebo. METHODS: A 2 × 2 factorial, randomized, blinded, multicenter trial enrolled patients older than 45 yr who had cardiovascular risk factors undergoing major noncardiac surgery. Factorial randomization allocated patients to one of two oxygen interventions from intubation and at 2 h after surgery, as well as antioxidant intervention or matching placebo. Antioxidants were 3 g IV vitamin C and 100 mg/kg N-acetylcysteine. The primary outcome was the degree of myocardial injury assessed by the area under the curve for high-sensitive troponin within the first 3 postoperative days. RESULTS: The authors randomized 600 participants from April 2018 to January 2020 and analyzed 576 patients for the primary outcome. Baseline and intraoperative characteristics did not differ between groups. The primary outcome was 35 ng · day/l (19 to 58) in the 80% oxygen group; 35 ng · day/l (17 to 56) in the 30% oxygen group; 35 ng · day/l (19 to 54) in the antioxidants group; and 33 ng · day/l (18 to 57) in the placebo group. The median difference between oxygen groups was 1.5 ng · day/l (95% CI, -2.5 to 5.3; P = 0.202) and -0.5 ng · day/l (95% CI, -4.5 to 3.0; P = 0.228) between antioxidant groups. Mortality at 30 days occurred in 9 of 576 patients (1.6%; odds ratio, 2.01 [95% CI, 0.50 to 8.1]; P = 0.329 for the 80% vs. 30% oxygen groups; and odds ratio, 0.79 [95% CI, 0.214 to 2.99]; P = 0.732 for the antioxidants vs. placebo groups). CONCLUSIONS: Perioperative interventions with high inspiratory oxygen fraction and antioxidants did not change the degree of myocardial injury within the first 3 days of surgery. This implies safety with 80% oxygen and no cardiovascular benefits of vitamin C and N-acetylcysteine in major noncardiac surgery.

Supplemental oxygen for traumatic brain injury: A systematic review.

BACKGROUND: Oxygen supplementation is recommended after traumatic brain injury (TBI) but excessive oxygen may be harmful. The aim of this study was to investigate the effect of supplemental oxygen or high/low inspiratory oxygen fraction (FiO2 ) for TBI patients on in-hospital mortality. METHODS: We searched Medline (Pubmed), EMBASE and the Cochrane Library for interventional and observational studies fulfilling the following criteria: TBI patients >17 years (population); initial use of supplemental oxygen/high (≥0.6) FiO2 (intervention) vs no supplemental oxygen/low (<0.6) FiO2 (control) for spontaneously breathing or mechanically ventilated TBI patients, respectively with in-hospital mortality as primary outcome. Secondary outcomes were 30-day and 1-year mortality, length of stay in hospital or intensive care unit, days on mechanical ventilation, complications, and neurological impairment. RESULTS: We screened 4846 citations. Two interventional studies comparing high vs low FiO2 for mechanically ventilated TBI patients were included. No difference in in-hospital mortality was found. The first study found a statistically significant shorter length of stay in the intensive care unit for the high FiO2 -group (6.5 [4.6-11.4] vs. 11.4 [5.8-17.2] days, p = 0.02). The second study found a lower disability at 6 months in the high FiO2 -group with low disability in 25 (73.5%) vs. 15 (44.1%), moderate disability in 9 (26.5%) vs. 16 (47.1%), and severe disability in 0 (0.0%) vs. 3 (8.8%), p = 0.02. CONCLUSION: Evidence on the effect of initial use of high/low FiO2 for TBI patients on in-hospital mortality was extremely limited. Evidence on the use of supplemental oxygen for spontaneously breathing TBI patients is lacking.

Rocuronium 0.3 or 0.9 mg/kg comparing onset time, duration of action, and intubating conditions in patients 80 years and older: A randomized study.

BACKGROUND: Limited data exist about the optimal dose of rocuronium for intubation in elderly patients. We hypothesized that rocuronium 0.9 mg/kg would lead to a shorter onset time than 0.3 mg/kg in patients above 80 years. METHODS: Thirty-four patients were randomized to either rocuronium 0.3 or 0.9 mg/kg. The primary outcome was onset time defined as time to train-of-four (TOF) count of 0. Other outcomes included duration of action (time to TOF ratio >0.9), proportion of excellent intubating conditions using the Fuchs-Buder scale and tracheal intubating conditions using the Intubating Difficulty Scale (IDS). RESULTS: Rocuronium 0.9 mg/kg resulted in shorter onset time compared to rocuronium 0.3 mg/kg; 108 s (SD 40) vs. 228 s (SD 140) (difference: 119 s [95% CI: 41-196], p = .005), respectively. However, in 66% of the patients receiving rocuronium 0.3 mg/kg a TOF count of 0 was not obtained. Duration of action was longer after rocuronium 0.9 mg/kg: 118 min (SD 43) vs. 46 min (SD 13) (difference: 72 min [95% CI: 49-95] p < .0001), and a greater proportion of excellent intubating conditions (Fuchs-Buder) was obtained; 11/16 (69%) vs 4/18 (22%) (p = .006). No difference was found regarding IDS score. CONCLUSION: Rocuronium 0.9 mg/kg resulted in a shorter onset time compared to rocuronium 0.3 mg/kg in patients above 80 years of age. In 66% of the patients receiving rocuronium 0.3 mg/kg a TOF count of 0 was not obtained.

Biomarkers of Cerebral Injury for Prediction of Postoperative Cognitive Dysfunction in Patients Undergoing Cardiac Surgery.

OBJECTIVES: To assess the ability of the biomarkers neuron-specific enolase (NSE), tau, neurofilament light chain (NFL), and glial fibrillary acidic protein (GFAP) to predict postoperative cognitive dysfunction (POCD) at discharge in patients who underwent cardiac surgery. DESIGN: Post hoc analyses (with tests being prespecified before data analyses) from a randomized clinical trial. SETTING: Single-center study from a primary heart center in Denmark. PARTICIPANTS: Adult patients undergoing elective or subacute on-pump coronary artery bypass grafting and/or aortic valve replacement. INTERVENTIONS: Blood was collected before induction of anesthesia, after 24 hours, after 48 hours, and at discharge from the surgical ward. The International Study of Postoperative Cognitive Dysfunction test battery was applied to diagnose POCD at discharge and after three months. Linear mixed models of covariance were used to assess whether repeated measurements of biomarker levels were associated with POCD. Receiver operating characteristic (ROC) curves were applied to assess the predictive value of each biomarker measurement for POCD. MEASUREMENTS AND MAIN RESULTS: A total of 168 patients had biomarkers measured at baseline, and 47 (28%) fulfilled the POCD criteria at discharge. Patients with POCD at discharge had significantly higher levels of tau (p = 0.02) and GFAP (p = 0.01) from baseline to discharge. The biomarker measurements achieving the highest area under the ROC curve for prediction of POCD at discharge were NFL measured at discharge (AUC, 0.64; 95% confidence interval [CI], 0.54-0.73), GFAP measured 48 hours after induction (AUC, 0.64; 95% CI, 0.55-0.73), and GFAP measured at discharge (AUC, 0.64; 95% CI, 0.54-0.74), corresponding to a moderate predictive ability. CONCLUSIONS: Postoperative serum levels of tau and GFAP were significantly elevated in cardiac surgery patients with POCD at discharge, however, the biomarkers achieved only modest predictive abilities for POCD at discharge. Postoperative levels of NSE were not associated with POCD at discharge.

Neuroinflammatory markers associate with cognitive decline after major surgery: Findings of an explorative study.

OBJECTIVE: Long-term cognitive decline is an adverse outcome after major surgery associated with increased risk for mortality and morbidity. We studied the cerebrospinal fluid (CSF) and serum biochemical inflammatory response to a standardized orthopedic surgical procedure and the possible association with long-term changes in cognitive function. We hypothesized that the CSF inflammatory response pattern after surgery would differ in patients having long-term cognitive decline defined as a composite cognitive z score of ≥1.0 compared to patients without long-term cognitive decline at 3 months postsurgery. METHODS: Serum and CSF biomarkers of inflammation and blood-brain barrier (BBB) integrity were measured preoperatively and up to 48 hours postoperatively, and cognitive function was assessed preoperatively and at 2 to 5 days and 3 months postoperatively. RESULTS: Surgery was associated with a pronounced increase in inflammatory biomarkers in both CSF and blood throughout the 48-hour study period. A principal component (PC) analysis was performed on 52 inflammatory biomarkers. The 2 first PC (PC1 and PC2) construct outcome variables on CSF biomarkers were significantly associated with long-term cognitive decline at 3 months, but none of the PC construct serum variables showed a significant association with long-term cognitive decline at 3 months. Patients both with and patients without long-term cognitive decline showed early transient increases of the astroglial biomarkers S-100B and glial fibrillary acidic protein in CSF, and in BBB permeability (CSF/serum albumin ratio). INTERPRETATION: Surgery rapidly triggers a temporal neuroinflammatory response closely associated with long-term cognitive outcome postsurgery. The findings of this explorative study require validation in a larger surgical patient cohort. Ann Neurol 2020;87:370-382.

Association between cerebrospinal fluid biomarkers of neuronal injury or amyloidosis and cognitive decline after major surgery.

BACKGROUND: Postoperative neurocognitive decline is a frequent complication in adult patients undergoing major surgery with increased risk for morbidity and mortality. The mechanisms behind cognitive decline after anaesthesia and surgery are not known. We studied the association between CSF and blood biomarkers of neuronal injury or brain amyloidosis and long-term changes in neurocognitive function. METHODS: In patients undergoing major orthopaedic surgery (knee or hip replacement), blood and CSF samples were obtained before surgery and then at 4, 8, 24, 32, and 48 h after skin incision through an indwelling spinal catheter. CSF and blood concentrations of total tau (T-tau), neurofilament light, neurone-specific enolase and amyloid ß (Aß1-42) were measured. Neurocognitive function was assessed using the International Study of Postoperative Cognitive Dysfunction (ISPOCD) test battery 1-2 weeks before surgery, at discharge from the hospital (2-5 days after surgery), and at 3 months after surgery. RESULTS: CSF and blood concentrations of T-tau, neurone-specific enolase, and Aß1-42 increased after surgery. A similar increase in serum neurofilament light was seen with no overall changes in CSF concentrations. There were no differences between patients having a poor or good late postoperative neurocognitive outcome with respect to these biomarkers of neuronal injury and Aß1-42. CONCLUSIONS: The findings of the present explorative study showed that major orthopaedic surgery causes a release of CSF markers of neural injury and brain amyloidosis, suggesting neuronal damage or stress. We were unable to detect an association between the magnitude of biomarker changes and long-term postoperative neurocognitive dysfunction.

Supplemental oxygen therapy in trauma patients: An exploratory registry-based study.

BACKGROUND: Supplemental oxygen (SO) is one of the most commonly administered drugs in trauma patients and is recommended by guidelines. However, evidence supporting uniform administration is sparse, and excess oxygen use has been shown to be harmful in other patient populations. We hypothesized that SO may be harmful in patients with oxygen saturation > 97%. METHODS: Patients with available information on SO-therapy in the American Trauma Quality Improvement Program 2017 database were included. Patients were categorized into 3 groups according to Emergency Department (ED) oxygen saturation: (1) saturation < 94%; (2) saturation 94%-97%; (3) saturation 98%-100%. Primary outcome was in-hospital mortality with comparisons made between patients who received SO or not. Secondary outcome was acute respiratory distress syndrome (ARDS). Patients were compared after propensity score matching. RESULTS: Overall, 864 340 patients were identified. Mean age was 47.4 ± 24.4 years, and median injury severity score was 9. SO was associated with an increased risk of in-hospital mortality: (all patients: adjusted odds ratio [aOR] with 95% confidence interval [CI] 3.07 [2.92-3.22], ED saturation <94%: 2.63 [2.38-2.91], ED saturation 94%-97%: 2.71 [2.47-2.97], ED saturation >97%: 3.38 [3.16-3.61]. Same pattern was seen for in-hospital ARDS: (aOR 1.79, 95% CI [1.59-2.02], ED saturation <94%: aOR 1.75, 95% CI [1.37-2.24], ED saturation 94%-97%: aOR 1.81, 95% CI [1.43-2.29, ED saturation >97%: aOR 2.31, 95% CI [1.92-2.79]). CONCLUSION: Based on propensity matched, registry data for trauma patients, the administration of SO was associated with a higher incidence of in-hospital mortality and ARDS. The highest risk was found in patients with an ED saturation >97%.

Serum-neuroproteins, near-infrared spectroscopy, and cognitive outcome after beach-chair shoulder surgery: Observational cohort study analyses.

BACKGROUND: Cerebral hypoxia may occur during surgery but currently used cerebral oxygenation saturation (rSO2) monitors remain controversial with respect to improving clinical outcome. Novel neuroprotein biomarkers are potentially released into systemic circulation and combined with near-infrared spectroscopy (NIRS) could clarify the presence of per-operative cerebral hypoxia. We investigated changes to serum-neuroprotein concentrations post-surgically, paired with NIRS and cognitive outcome, in patients operated in the beach chair position (BCP). METHODS: A prospective cohort in 28 shoulder surgery patients placed in the BCP. Blood samples were collected before induction of anaesthesia, and 2 hours and 3-5 days post-operatively. We analysed blood levels of biomarkers including tau and neurofilament light (NFL). We post hoc assessed the cross-wise relationship between biomarker levels and post-surgical changes in cognitive function and intraoperatively monitored rSO2 from NIRS. RESULTS: Serum-NFL decreased from 24.2 pg/mL to 21.5 (P = .02) 2 hours post-operatively, then increased to 27.7 pg/mL on day 3-5 (P = .03). Conversely, s-tau increased from 0.77 pg/mL to 0.98 (2 h), then decreased to 0.81 on day 3-5 (P = .08). In 14/28 patients, episodic rSO2 below 55% occurred, and the duration < 55% was correlated to change in s-tau (P < .05). The cognitive function z-score at 1 week and 3 mo. correlated to the change in tau (P = .01), but not to NFL. CONCLUSION: Some biomarkers were significantly changed with surgery in the beach chair position. The change was at some points associated to post-operative cognitive decline, and to intraoperative low rSO2. (237).

Anesthesiologists' airway management expertise: Identifying subjective and objective knowledge gaps.

BACKGROUND: Failure in airway management continues to cause preventable patient harm, and the recommended continuing education is challenged by anesthesiologists' unknown knowledge gaps. This study aimed to identify anesthesiologists' subjective and objective knowledge gaps as well as areas where anesthesiologists are incorrect and unaware. METHODS: An adaptive E-learning program with 103 questions on adult airway management was used for subjective and objective assessment of anesthesiologists' knowledge. All anesthesiologists in the Capital Region of Denmark were invited to participate. RESULTS: The response rate was 67% (191/285). For preoperative planning, participants stated low confidence (subjective assessment) regarding predictors of difficult airway management in particular (69.1%-79.1%). Test scores (objective assessment) were lowest for obstructive sleep apnea as a predictor of difficult airway management (28.8% correct), with participants being incorrect and unaware in 33.5% of the answers. For optimization of basic techniques, the lowest confidence ratings related to patient positioning and prediction of difficulties (57.4%-83.2%), which agreed with the lowest test scores. Concerning advanced techniques, videolaryngoscopy prompted the lowest confidence (72.4%-85.9%), while emergency cricothyrotomy resulted in the lowest test scores (47.4%-67.8%). Subjective and objective assessments correlated and lower confidence was associated with lower test scores: preoperative planning [r = -.58, P < .001], optimization of basic techniques [r = -.58, P = .002], and advanced techniques [r = -.71, P < .001]. CONCLUSION: We identified knowledge gaps in important areas of adult airway management with differing findings from the subjective and objective assessments. This underlines the importance of objective assessment to guide continuing education.

A blinded randomized study comparing intubating conditions after either rocuronium 0.6 mg·kg-1 or remifentanil 2 µg·kg-1 in elderly patients.

BACKGROUND: To facilitate tracheal intubation, either a neuromuscular blocking agent or a bolus dose of remifentanil can be administered. We hypothesized that rocuronium 0.6 mg·kg-1 provided a larger proportion of excellent intubating conditions compared to remifentanil 2 µg·kg-1 in patients above 80 years. METHODS: A total of 78 patients were randomized to either rocuronium 0.6 mg·kg-1 or remifentanil 2 µg·kg-1 . General anaesthesia was initiated with fentanyl and propofol. Two minutes after the administration of either rocuronium or remifentanil, tracheal intubating conditions were evaluated using the Fuchs-Buder scale by a blinded investigator, and our primary outcome was the proportion of patients presenting intubating conditions deemed as excellent. Further outcomes included the Intubating Difficulty Scale (IDS), hoarseness or sore throat 24 h postoperatively, and intervention against hypotension. RESULTS: No difference in the occurrence of excellent intubating conditions was found comparing the rocuronium group with the remifentanil group; 10 (28%) versus 15 (39%) (p = .29), respectively, relative risk = 0.72. Interventions against hypotension were used in 24 (67%) versus 28 (74%) (p = .51), respectively. Hoarseness and sore throat 24 h postoperatively were found in 37% versus 35% p = .86, and 14% versus 5% p = .20, respectively. The IDS score was 2 versus 2 p = .48. CONCLUSION: No difference in intubating conditions was found 2 min after the administration of either rocuronium 0.6 mg·kg-1 or remifentanil 2 µg·kg-1 in patients aged above 80 years. Intubation conditions were less than optimal in a large proportion of this patient population. CLINICAL TRIALS REGISTRATION: NCT04287426.

Incidence of in-hospital cardiac arrest at general wards before and after implementation of an early warning score.

BACKGROUND: In order to reduce the incidence of in-hospital cardiac arrest (IHCA) at general wards, medical emergency teams (MET) were implemented in the Capital Region of Denmark in 2012 as the efferent part of a track and trigger system. The National Early Warning Score (NEWS) system became the afferent part. This study aims at investigating the incidence of IHCA at general wards before and after the implementation of the NEWS system. MATERIAL AND METHODS: We included patients at least 18 years old with IHCA at general wards in our hospital in the periods of 2006 to 2011 (pre-EWS group) and 2013 to 2018 (post-EWS group). Data was obtained from a local database and the National In-Hospital Cardiac Arrest Registry (DANARREST). We calculated incidence rate ratios (IRR) for IHCA at general wards with 95% confidence interval (95% CI). Odds ratios (OR) for return of spontaneous circulation (ROSC) and 30-day survival were also calculated with 95% CI. RESULTS: A total of 444 IHCA occurred before the implementation of NEWS at general wards while 494 IHCA happened afterwards. The incidence rate of IHCA at general wards was 1.13 IHCA per 1000 admissions in the pre-EWS group (2006-2011) and 1.11 IHCA per 1000 admissions in the post-EWS group (2013-2018). The IRR between the two groups was 0.98 (95% CI [0.86;1.11], p = 0.71). The implementation did not affect the chance of ROSC with a crude OR of 1.14 (95% CI [0.88;1.47], p = 0.32) nor did it change the 30-day survival with a crude OR 1.30 (95% CI [0.96;1.75], p = 0.09). CONCLUSION: Implementation of the EWS system at our hospital did not decrease the incidence rate of in-hospital cardiac arrest at general wards.

Search and Rescue Helicopters for Emergency Medical Service Assistance: A Retrospective Study.

OBJECTIVE: The time until treatment is a crucial factor for the outcome after medical emergencies. One way of reducing transportation time is the use of helicopter-based emergency medical services, but poor weather conditions, commitment to another mission, or technical problems may limit the availability. In these cases, military search and rescue (SAR) helicopters can be used. The aim of this study was to investigate the role of SAR helicopters in the civilian emergency medical system. METHODS: We conducted a retrospective study of SAR mission reports and SAR medical records collected from the archives of the Royal Danish Air Force for the years 2016 and 2017. RESULTS: A total of 1,262 mission reports were included with a total of 628 medical records available in the study period. There were 490 of 1,246 (39.3%) missions involving patients. Interhospital transfers accounted for 306 of 604 (50.7%) of cases, whereas island evacuation constituted 110 of 604 (18.2%) cases. The most prevalent suspected diagnosis was acute coronary syndrome (14.4%). The 30-day survival rate was 87.6%. CONCLUSION: The military SAR helicopters were most commonly activated for civilian emergency medical service mission assistance due to poor weather conditions. The most frequent medical condition was acute coronary syndrome.

Smoking and risk of surgical bleeding: nationwide analysis of 5,452,411 surgical cases.

BACKGROUND: Although smoking is associated with several postoperative complications, a possible association with surgical bleeding remains unclear. We examined if smoking is associated with a higher risk of surgical bleeding. STUDY DESIGN AND METHODS: We included patients from the American College of Surgeons National Surgical Quality Improvement Program 2007-2016 from 680 hospitals across the United States. Patients with information on age, sex, surgical specialty, and smoking status were included. Surgical bleeding was defined as 1 or more red blood cell (RBC) units transfused intraoperatively to 72 hours postoperatively. The association between smoking and surgical bleeding was examined using logistic regressions adjusted for age, sex, body mass index, ethnicity, comorbidities, laboratory values, American Society of Anesthesiologists score, type of anesthesia, duration of surgery, work relative value unit (surrogate for operative complexity), surgical specialty, and procedure year. RESULTS: A total of 5,452,411 cases were recorded, of whom 19% smoked and 6% received transfusion. Odds ratios for transfusion were 1.06 (95% confidence interval [CI], 1.05-1.07) for smokers versus nonsmokers and 1.06 (95% CI, 1.04-1.09) for current smokers versus never-smokers. Odds ratios for cumulative smoking were 0.97 (95% CI, 0.95-1.00) for greater than 0 to 20 versus 0 pack-years, 1.04 (95% CI, 1.01-1.07) for greater than 20 to 40, and 1.12 (95% CI, 1.09-1.15) for greater than 40 (p for trend < 0.001). Hazard ratios for reoperations due to any cause and to bleeding were 1.28 (95% CI, 1.27-1.31) and 0.99 (95% CI, 0.93-1.04). CONCLUSION: Smoking was associated with a higher risk of RBC transfusion as a proxy for surgical bleeding across all surgical specialties combined.