The association between intraoperative hypotension and postoperative delirium- a retrospective cohort analysis.

BACKGROUND: Intraoperative hypotension might contribute to the development of postoperative delirium through inadequate cerebral perfusion. However, evidence regarding the association between intraoperative hypotension and postoperative delirium is equivocal. We therefore tested the hypothesis that in patients>70 years having elective non-cardiac surgery, intraoperative hypotension is associated with postoperative delirium. METHODS: We conducted a retrospective cohort analysis of patients >70 years who underwent elective non-cardiac surgery in a single tertiary academic center between 2020 and 2021. Intraoperative hypotension was quantified as the area under a mean arterial pressure (MAP) threshold of 65 mmHg. Postoperative delirium was defined as a collapsed composite outcome including positive 4A's test during the initial 2 postoperative days, and/or delirium identification using the Chart-based Delirium Identification Instrument. The association between hypotension and postoperative delirium was assessed using multivariable logistic regression, adjusting for potential confounding variables. Several sensitivity analyses were performed using similar regression models. RESULTS: In total, 2352 patients were included (median age 76 years, 1112 (47%) women, 1166 (50%) ASA score≥3, and 698 (31%) having high-risk surgeries). The median [IQR] intraoperative AUC of MAP<65 mmHg was 28 [0,103] mmHg. min. The overall incidence of postoperative delirium was 14% (327/2352). After adjustment for potential confounding variables, hypotension was not associated with postoperative delirium. Compared to the 1st quartile of AUC of MAP<65 mmHg, patients in the 2nd, 3rd, and 4th quartiles did not have more postoperative delirium, with adjusted odds ratio (aOR) of 0.94 (95% confidence interval (CI) 0.64-1.36; P=0.73), 0.95 (0.66-1.36; P=0.78), and 0.95 (0.65-1.36; P=0.78), respectively. Intraoperative hypotension was also not associated with postoperative delirium in any of the sensitivity and sub-group analyses performed. CONCLUSIONS: To the extent of hypotension observed in our cohort, our results suggest that intraoperative hypotension is not associated with postoperative delirium in elderly patients having elective non-cardiac surgery.

The Prevalence of Post-traumatic Stress Disorder as Part of Post-ICU Syndrome among Israeli ICU Survivors.

BACKGROUND: Survivors of critical illness are at increased risk of long-term impairments, referred to as post-intensive care unit (ICU) syndrome (PICS). Post-traumatic stress disorder (PTSD) is common among ICU survivors with reported rates of up to 27%. The prevalence of PTSD among Israeli ICU survivors has not been reported to date. OBJECTIVES: To evaluate the prevalence of new onset PTSD diagnosed in a post-ICU clinic at a tertiary center in Israel. METHODS: We conducted a retrospective, single center, cohort study. Data were collected from medical records of all patients who visited the Tel Aviv Sourasky Medical Center post-ICU clinic between October 2017 and June 2020. New onset PTSD was defined as PTSD diagnosed by a certified board psychiatrist during the post-ICU clinic visit. Data were analyzed using descriptive statistics. RESULTS: Overall, 39 patients (mean age 51 ± 17 years, 15/39 females [38%]) attended the post-ICU clinic during the study period. They were evaluated 82 ± 57 days after hospital discharge. After excluding 7 patients due to missing proper psychiatric analysis, 32 patients remained eligible for the primary analysis. New PTSD was diagnosed in one patient (3%). CONCLUSIONS: We found lower incidence of PTSD in our cohort when compared to existing literature. Possible explanations include different diagnostic tools and low risk factors rate. Unique national, cultural, and/or religious perspectives might have contributed to the observed low PTSD rate. Further research in larger study populations is required to establish the prevalence of PTSD among Israeli ICU survivors.

Preoperative Cognitive Impairment and Postoperative Delirium in Elderly Surgical Patients: A Retrospective Large Cohort Study (The CIPOD Study).

OBJECTIVE: To test the hypothesis that in surgical patients ≥70 years, preoperative cognitive impairment is independently associated with postoperative delirium. BACKGROUND: Postoperative delirium is common among elderly surgical patients and is associated with longer hospitalization and significant morbidity. Some evidence suggest that baseline cognitive impairment is an important risk factor. Routine screening for both preoperative cognitive impairment and postoperative delirium is recommended for older surgical patients. As of 2019, we implemented such routine perioperative screening in all elective surgical patients ≥70 years. METHODS: Retrospective single-center analysis of prospectively collected data between January and December 2020. All elective noncardiac surgical patients ≥70 years without pre-existing dementia were included. Postoperative delirium, defined as 4A's test score ≥4, was evaluated in the postanesthesia care unit and during the initial 2 postoperative days. Patients' electronic records were also reviewed for delirium symptoms and other adverse outcomes. RESULTS: Of 1518 eligible patients, 1338 (88%) were screened preoperatively [mean (SD) age 77 (6) years], of whom 21% (n=279) had cognitive impairment (Mini-Cog score ≤2). Postoperative delirium occurred in 15% (199/1338). Patients with cognitive impairment had more postoperative delirium [30% vs. 11%, adjusted odds ratio (95% confidence interval) 3.3 (2.3-4.7)]. They also had a higher incidence of a composite of postoperative complications [20% vs. 12%, adjusted odds ratio: 1.8 (1.2-2.5)], and median 1-day longer hospital stay [median (interquartile range): 6 (3,12) vs. 5 (3,9) days]. CONCLUSIONS: One-fifth of elective surgical patients ≥70 years present to surgery with preoperative cognitive impairment. These patients are at increased risk of postoperative delirium and major adverse outcomes.

Virtual reality and 3D printing in clinical anesthesia: a case series of two years' experience in a single tertiary medical centre.

PURPOSE: Anatomically correct patient-specific models made from medical imaging can be printed on a three-dimensional (3D) printer or turned into a virtual reality (VR) program. Until recently, use in anesthesia has been limited. In 2019, the anesthesia department at Tel Aviv Medical Center launched a 3D program with the aim of using 3D modelling to assist in preoperative anesthesia planning. METHODS: A retrospective review of all relevant patients between July 2019 and June 2021 referred for preoperative airway planning with 3D modelling. Patient files were reviewed for correlation between the model-based airway plan and the actual airway plan, the type of model used, and any anesthetic complications related to airway management. RESULTS: Twenty patients were referred for 3D modelling. Of these, 15 models were printed, including 12 children requiring one lung ventilation. Five patients had VR reconstructions, including three with mediastinal masses. One patient had both a 3D-printed model and a VR reconstruction. There were two cases (10%) where the model plan did not correlate with the final airway plan and one case where a model could not be created because of poor underlying imaging. For the remaining 17 cases, the plan devised on the model matched the final airway plan. There were no anesthetic complications. CONCLUSIONS: Three-dimensional modelling and subsequent printing or VR reconstruction are feasible in clinical anesthesia. Its routine use for patients with challenging airway anatomy correlated well with the final clinical outcome in most cases. High-quality imaging is essential.

RéSUMé: OBJECTIF: Des modèles anatomiquement corrects spécifiques à un·e patient·e réalisés à partir de l'imagerie médicale peuvent être imprimés sur une imprimante tridimensionnelle (3D) ou transformés en programme de réalité virtuelle (RV). Jusqu'à récemment, l'utilisation de cette modalité était limitée en anesthésie. En 2019, le service d'anesthésie du centre médical de Tel Aviv a lancé un programme 3D dans le but d'utiliser la modélisation 3D pour faciliter la planification préopératoire de l'anesthésie. MéTHODE: Nous avons réalisé un examen rétrospectif de toute la patientèle concernée référée pour une planification préopératoire des voies aériennes avec modélisation 3D entre juillet 2019 et juin 2021. Les dossiers des patient·es ont été examinés pour déterminer la corrélation entre le plan de prise en charge des voies aériennes fondé sur le modèle et le plan fondé sur les voies aériennes réelles, le type de modèle utilisé et toute complication anesthésique liée à la prise en charge des voies aériennes. RéSULTATS: Vingt patient·es ont été référé·es pour la modélisation 3D. À partir de cette cohorte, 15 modèles ont été imprimés, dont 12 pour des enfants nécessitant une ventilation pulmonaire. Cinq patient·es ont bénéficié de reconstructions en RV, dont trois avec des masses médiastinales. Un modèle imprimé en 3D et une reconstruction en RV ont été créés pour une personne. Il y a eu deux cas (10 %) où le plan modèle n'était pas corrélé avec le plan des voies aériennes final et un cas où il n'a pas été possible de créer un modèle en raison d'une mauvaise imagerie sous-jacente. Pour les 17 cas restants, le plan conçu sur le modèle correspondait au plan final de prise en charge des voies aériennes. Il n'y a pas eu de complications anesthésiques. CONCLUSION: La modélisation tridimensionnelle et l'impression ultérieure ou la reconstruction en RV sont réalisables en anesthésie clinique. Leur utilisation systématique pour les patient·es présentant une anatomie difficile au niveau des voies aériennes était bien corrélée avec le résultat clinique final dans la plupart des cas. Une imagerie de haute qualité est essentielle.

Anesthesia-induced loss of consciousness disrupts auditory responses beyond primary cortex.

Despite its ubiquitous use in medicine, and extensive knowledge of its molecular and cellular effects, how anesthesia induces loss of consciousness (LOC) and affects sensory processing remains poorly understood. Specifically, it is unclear whether anesthesia primarily disrupts thalamocortical relay or intercortical signaling. Here we recorded intracranial electroencephalogram (iEEG), local field potentials (LFPs), and single-unit activity in patients during wakefulness and light anesthesia. Propofol infusion was gradually increased while auditory stimuli were presented and patients responded to a target stimulus until they became unresponsive. We found widespread iEEG responses in association cortices during wakefulness, which were attenuated and restricted to auditory regions upon LOC. Neuronal spiking and LFP responses in primary auditory cortex (PAC) persisted after LOC, while responses in higher-order auditory regions were variable, with neuronal spiking largely attenuated. Gamma power induced by word stimuli increased after LOC while its frequency profile slowed, thus differing from local spiking activity. In summary, anesthesia-induced LOC disrupts auditory processing in association cortices while relatively sparing responses in PAC, opening new avenues for future research into mechanisms of LOC and the design of anesthetic monitoring devices.

Pro-Con Debate: Cardiac Troponin Measurement as Part of Routine Follow-up of Myocardial Damage Following Noncardiac Surgery.

Elevated troponin levels within 3 days of surgery, independent of the presence of symptoms, are strongly linked to increased risk of short- and long-term morbidity and mortality. However, the value of screening with troponin measurements is controversial. The Canadian Cardiovascular Society guidelines on perioperative cardiac risk assessment and management for patients who undergo noncardiac surgery recommends measuring daily troponin for 48 to 72 hours after surgery in high-risk patients. Nevertheless, others doubt this recommendation, in part because postoperative elevated levels of troponin describe very little in terms of disease or event-specific pathogenesis and etiology, and thus, tailoring an intervention remains a challenge. This Pro-Con debate offers evidence-based data to stimulate physician understanding of daily practice and its significance in this matter, and assist in determining whether to use (Pro) or not to use (Con) this surveillance.

Indications and diagnosis-specific features of maternal and neonatal peripartum intensive care unit admissions: A retrospective study.

BACKGROUND: Although peripartum intensive care unit admission indications are well-reported, clinical and laboratory details rarely are. We described admission indications and categorised laboratory values and vital signs according to admission diagnosis. METHODS: Retrospective Institutional Review Board approved study. We identified intensive care unit admission diagnosis, laboratory values and vital signs from patient charts. Groups were compared according to admission diagnoses. Data were analysed using descriptive statistics. RESULTS: We included 91 general intensive care unit admissions among 56,865 deliveries (2011-2015) with complete data. The most common admission diagnosis was postpartum haemorrhage followed by hypertensive diseases of pregnancy and respiratory complications. Women with postpartum haemorrhage had lower mean (standard deviation) platelet counts (120.2 (45.8) vs. 181.2 (109.9), p = .003) and temperatures (35.7 (1.1) vs. 36.5 (1.2), p = .002). Women with hypertensive diseases of pregnancy had higher mean (standard deviation) blood pressures (systolic 150.4 (29.1) vs. 127.4 (21.0), p = .013, diastolic 100.3 (18.7) vs. 76.1 (16.1), p = .001), creatinine (1.1 (0.6) vs. 0.8 (0.3), p = .003), urea (14.6 (7.7) vs. 10.5 (4.7), p = .005) and liver enzymes, including aspartate transaminase (258.4 (297.0) vs. 41.4 (42.9), p = .000), alanine transaminase (184.4 (199.2) vs. 35.1 (75.9), p = .000), and alkaline phosphatase (166.6 (112.6) vs. 96.0 (60.0), p = .006). Women with respiratory complications had lower mean (standard deviation) oxygen saturations (93.7 (6.1) vs. 98.0 (2.6), p = .000), and higher mean (standard deviation) temperatures (37.1 (0.8) vs. 36.0 (1.2), p = .001). CONCLUSIONS: We report differences in laboratory values and vital signs, according to intensive care unit admission diagnosis. Recognising these differences might help individualise patient assessment and care.

Changes in mean systemic filling pressure as an estimate of hemodynamic response to anesthesia induction using propofol.

BACKGROUND: Even a small change in the pressure gradient between the venous system and the right atrium can have significant hemodynamic effects. Mean systemic filling pressure (MSFP) is the driving force of the venous system. As a result, MSFP has a significant effect on cardiac output. We aimed to test the hypothesis that the hemodynamic instability during induction of general anesthesia by intravenous propofol administration is caused by changes in MSFP. METHODS: We prospectively collected data from 15 patients undergoing major surgery requiring invasive hemodynamic monitoring. Hemodynamic parameters, including MSFP, were measured before and after propofol administration and following intubation, using venous return curves at a no-flow state induced by a pneumatic tourniquet. RESULTS: A significant decrease in MSFP was observed in all study patients after propofol administration (median (IQR) pressure 17 (9) mmHg compared with 25 (7) before propofol administration, p = 0.001). The pressure gradient for venous return (MSFP - central venous pressure; CVP) also decreased following propofol administration from 19 (8) to 12 (6) mmHg, p = 0.001. Central venous pressure did not change. CONCLUSIONS: These results support the hypothesis that induction of anesthesia with propofol causes a marked reduction in MSFP. A possible mechanism of propofol-induced hypotension is reduction in preload due to a decrease in the venous vasomotor tone.

Perioperative Oral Pregabalin Results in Postoperative Pain Scores Equivalent to Those of Interscalene Brachial Plexus Block After Arthroscopic Rotator Cuff Repair: A Randomized Clinical Trial.

PURPOSE: To compare the analgesic effects of pregabalin to those of single-shot interscalene brachial plexus block (ISBPB) in adults having arthroscopic rotator cuff (RC) repair, as well as ISBPB's effect on postoperative opioid consumption, patient satisfaction, and opioid-related adverse effects. METHODS: In this randomized trial, 79 adults having arthroscopic RC repair were randomized to receive perioperative oral pregabalin (Lyrica, twice daily starting the evening before surgery, for a total of 4 doses) or single-shot ISBPB (20 ml of bupivacaine 0.25%). Intra- and postoperative management was standardized. The primary outcome was median self-reported pain score (on a visual analog scale of 0 to 100) at rest during the initial 10 postoperative days. Other outcomes included pain during activity, postoperative opioid consumption, opioid-related adverse effects, quality of recovery, and pain satisfaction score. RESULTS: Of 71 eligible patients, 59 were analyzed, of whom 29 received pregabalin and 30 received ISBPB. Groups were similar regarding demographic, baseline, and intraoperative variables. Median pain score at rest over the 10 postoperative days was 51 (interquartile range 26, 76) in the pregabalin group and 52 (22, 74) in the ISBPB group (difference 0.5 points; 95% confidence interval [CI] -3.2 to 6.3; P = .53). Opioid consumption during the initial 10 postoperative days was also similar (difference in median 90 mg of morphine equivalents; 95% CI -32 to 177.5; P = .12). No differences were found in any other outcome. CONCLUSIONS: Perioperative use of pregabalin in adults undergoing arthroscopic RC repair provided analgesia comparable to that of ISBPB for 10 days after surgery. LEVEL OF EVIDENCE: II, randomized controlled trial (high dropout rate).

Women anaesthesiologists' attitudes and reported barriers to career advancement in anaesthesia: a survey of the European Society of Anaesthesiology.

BACKGROUND: Previous studies have confirmed gender imbalance in anaesthesia leadership. Whether women anaesthesiologists aspire to career advancement has not been reported. This European Society of Anaesthesiology (ESA) survey explored anaesthesiologists' motivation to advance their careers into leadership positions, and to identify reported barriers to advancement. METHODS: ESA members (n=10 033, 5245 men, 3759 women, 1029 undefined) were invited to complete a 25-item, Internet-based survey, and responses were analysed thematically. RESULTS: In total, 3048 ESA members (1706 women, 1342 men, 30% of all members) responded to the survey. The majority were specialists, married or with a partner, and have children; 47% of women and 48% of men wish to pursue a leadership career. Barriers to career promotion noted by women were primarily attributed to work-private time considerations (extra workload and less personal time [84%], responsibility for care of family [65%], lack of part-time work opportunities [67%]), and the shift away from clinical work [59%]). Men respondents indicated the same barriers although the proportions were significantly lower. Considerations related to the partner (lack of support, career development of partner) were last on the list of variables reported by women as barriers. Importantly, many women noted deficiencies in leadership (68%) and research education (55%), and women role models (41%) and self-confidence (44%). CONCLUSIONS: This is the largest survey to date of women anaesthesiologists' view on career advancement. Despite the many barriers noted by women, they are as eager as men to assume leadership positions. The survey results help in identifying possible areas for intervention to assist in career development.

Anesthesia departments' readiness for the COVID-19 pandemic; a nationwide cross-sectional study in Israel.

BACKGROUND: The Coronavirus infectious disease 2019 (COVID-19) brings anesthesiologists and intensive care physicians to the mainstay of clinical workload and healthcare managements' focus. There are approximately 900 anesthesiologists in Israel, working in non-private hospitals. This nationwide cross-sectional study evaluated the readiness and involvement of anesthesia departments in Israel in management of the COVID-19 pandemic. The impact on anesthesiologists' health, workload, and clinical practices were also evaluated. METHODS: An online questionnaire was distributed to all of anesthesia department chairs in Israel on April 14th. Each response was identifiable on the hospital level only. Informed consent was waived since no patient data were collected. RESULTS: Response rate was 100%. A decrease of at least 40% in operating-room activity was reported by two-thirds of the departments. Anesthesiologists are leading the treatment of COVID-19 patients in 19/28 (68%) Israeli hospitals. Israel Society of Anesthesiologists' recommendations regarding intubation of COVID-19 patients were strictly followed (intubations performed by the most experienced available physician, by rapid-sequence induction utilizing video-laryngoscopy, while minimizing the number of people in the room - about 90% compliance for each). Anesthesiologists in most departments use standard personal protective equipment when caring for COVID-19 patients, including N95 masks, face shields, and water-proof gowns. Only one anesthesiologist across Israel was diagnosed with COVID-19 (unknown source of transmission). All department chairs reported emerging opportunities that advance the anesthesia profession: implementation of new technologies and improvement in caregivers' clinical capabilities (68% each), purchase of new equipment (96%), and increase in research activity (36%). CONCLUSIONS: This nationwide cross-sectional study had a complete response rate and therefore well-represents the anesthesia practice in Israel. We found that Israeli anesthesia departments are generally highly involved in the health system efforts to cope with the COVID-19 pandemic. Anesthesia and airway management are performed in a remarkably comparable manner and with proper protection of caregivers. Ambulatory anesthesia activity has dramatically decreased, but many departments find opportunities for improvement even in these challenging times.

Anesthesia for Patients Undergoing Anesthesia for Elective Thoracic Surgery During the COVID-19 Pandemic: A Consensus Statement From the Israeli Society of Anesthesiologists.

Anesthesia for thoracic surgery requires specialist intervention to provide adequate operating conditions and one-lung ventilation. The pandemic caused by severe acute respiratory syndrome-associated coronavirus 2 (SARS-CoV-2) is transmitted by aerosol and droplet spread. Because of its virulence, there is a risk of transmission to healthcare workers if appropriate preventive measures are not taken. Coronavirus disease 2019 (COVID-19) patients may show no clinical signs at the early stages of the disease or even remain asymptomatic for the whole course of the disease. Despite the lack of symptoms, they may be able to transfer the virus. Unfortunately, during current COVID-19 testing procedures, about 30% of tests are associated with a false-negative result. For these reasons, standard practice is to assume all patients are COVID-19 positive regardless of swab results. Here, the authors present the recommendations produced by the Israeli Society of Anesthesiologists for use in thoracic anesthesia for elective surgery during the COVID-19 pandemic for both the general population and COVID-19-confirmed patients. The objective of these recommendations is to make changes to some routine techniques in thoracic anesthesia to augment patients' and the medical staff's safety.

Machine learning applied to multi-sensor information to reduce false alarm rate in the ICU.

Studies reveal that the false alarm rate (FAR) demonstrated by intensive care unit (ICU) vital signs monitors ranges from 0.72 to 0.99. We applied machine learning (ML) to ICU multi-sensor information to imitate a medical specialist in diagnosing patient condition. We hypothesized that applying this data-driven approach to medical monitors will help reduce the FAR even when data from sensors are missing. An expert-based rules algorithm identified and tagged in our dataset seven clinical alarm scenarios. We compared a random forest (RF) ML model trained using the tagged data, where parameters (e.g., heart rate or blood pressure) were (deliberately) removed, in detecting ICU signals with the full expert-based rules (FER), our ground truth, and partial expert-based rules (PER), missing these parameters. When all alarm scenarios were examined, RF and FER were almost identical. However, in the absence of one to three parameters, RF maintained its values of the Youden index (0.94-0.97) and positive predictive value (PPV) (0.98-0.99), whereas PER lost its value (0.54-0.8 and 0.76-0.88, respectively). While the FAR for PER with missing parameters was 0.17-0.39, it was only 0.01-0.02 for RF. When scenarios were examined separately, RF showed clear superiority in almost all combinations of scenarios and numbers of missing parameters. When sensor data are missing, specialist performance worsens with the number of missing parameters, whereas the RF model attains high accuracy and low FAR due to its ability to fuse information from available sensors, compensating for missing parameters.

Transient subcortical functional connectivity upon emergence from propofol sedation in human male volunteers: evidence for active emergence.

BACKGROUND: Emergence from sedation entails rapid increase in the levels of both awareness and wakefulness, the two axes of consciousness. Functional MRI (fMRI) studies of emergence from sedation often focus on the recovery period, with no description of the moment of emergence. We hypothesised that by focusing on the moment of emergence, novel insights, primarily about subcortical activity and increased wakefulness, will be gained. METHODS: We conducted a resting state fMRI analysis of 17 male subjects (20-40 yr old) gradually entering into and emerging from deep sedation (average computed propofol concentrations of 2.41 and 1.11 µg ml-1, respectively), using target-controlled infusion of propofol. RESULTS: Functional connectivity analysis revealed a robust spatiotemporal signature of return of consciousness, in which subcortical seeds showed transient positive correlations that rapidly turned negative shortly after emergence. Elements of this signature included four components of the ascending reticular activating system: the ventral tegmentum area, the locus coeruleus, median raphe, and the mammillary body. The involvement of the rostral dorsolateral pontine tegmentum, which is specifically impaired in comatose patients with pontine lesions, in emergence was previously unknown. CONCLUSIONS: Emergence from propofol sedation is characterised, and possibly driven, by a transient activation of brainstem loci. Some of these loci are known components of the ascending reticular activating system, whereas an additional locus was found that is also impaired in comatose patients.

Bradycardia During Laparoscopic Surgeries: A Retrospective Cohort Study.

BACKGROUND: A recent analysis found bradycardia during laparoscopy as a potential early warning sign of cardiac arrest. Knowledge regarding bradycardia frequency and its consequences during laparoscopy is limited. METHODS: Using the computerized record database, files of 9915 patients undergoing laparoscopic surgery, between June 2008 and August 2013 at a tertiary, academic medical center, were screened for intraoperative bradycardia (heart rate <50 beats/min for at least three consecutive measures). RESULTS: Intraoperative bradycardia occurred in 1540 (15.5%) patients, in the majority (945, 61.3%) heart rate decreased to <45 beats/min. Mean (SD) duration of bradycardia was 14.8 (16.8) min. Bradycardia was more prevalent in males, older patients, smokers, patients with comorbidities and those treated with ß, α and calcium channel blockers. The majority of events were related to CO2 insufflation and bolus opioid administration. In 1343 (87%), noteworthy decreases in blood pressure were recorded; the average (SD) drop in systolic blood pressure was 35 (21) mmHg. Pharmacological intervention to alleviate bradycardia was used in up to 23% of episodes. Bradycardia did not result in intraoperative cardiac arrest, neither did it increase the frequency of intensive care unit admission or mortality rate. CONCLUSION: Bradycardia is common during laparoscopy. Despite being more prevalent in older and sicker patients, bradycardia did not significantly affect outcome, suggesting that routine preventive measures do not need to be implemented. Rather, intraoperative bradycardia events should be wisely followed with prompt response, when hemodynamic perturbations occur, the threshold of which is yet to be defined.

Hyperchloremia and Diuresis in Children Undergoing Scoliosis Surgery: A Retrospective Cohort Study.

BACKGROUND: Hyperchloremia is frequent in adult surgical patients and is associated with renal dysfunction. Studies in surgical pediatric patients are lacking. OBJECTIVES: To identify both the incidence of postoperative hyperchloremia in children undergoing surgery for idiopathic and non-idiopathic scoliosis, and the association of postoperative hyperchloremia with intraoperative fluid management and postoperative diuresis. METHODS: The records of 74 children and adolescents who underwent elective scoliosis surgery were retrospectively evaluated. The primary endpoint was the incidence of serum chloride level ≥ 110 mEq/L at the end of surgery and 12 hours postoperatively. Secondary endpoints were the type and volume of administered fluids, 12 hours postoperative diuresis, and the incidence of postoperative oliguria. RESULTS: Hyperchloremia occurred in 55% of the patients at the end of surgery and in 52% 12 hours postoperatively. Hyperchloremic patients received larger intraoperative volume of 0.9% NaCl diluted cell-saver blood and 10% HAES than did normochloremic patients [median (interquartile range) 6.8 (2.5-11.0) ml/kg vs. 0 (0-7.3), P = 0.003 and 10.0 (0-12.8) vs. 4.4 (0-9.8), P = 0.02, respectively]. Additionally, when compared with normochloremic patients, diuresis during the first 12 hours postoperatively was lower in hyperchloremic patients. Postoperative oliguria (urine output < 0.5 ml/kg/hr for 12 hours) was diagnosed in 7 children (9%), of whom 6 were hyperchloremic at the end of surgery. CONCLUSIONS: Early postoperative hyperchloremia is common in children undergoing scoliosis repair surgery and may be attributed to the administration of 0.9% NaCl diluted cell-saver blood and 10% HAES. Postoperative hyperchloremia might be associated with postoperative oliguria.

Impaired liver regeneration after hepatectomy and bleeding is associated with a shift from hepatocyte proliferation to hypertrophy.

Extensive liver resections are common, and bleeding is frequent in these operations. Impaired regeneration after partial hepatectomy (PHx) may contribute to liver failure. We thus assessed the impact of acute bleeding on the liver regeneration progress after PHx and explored possible contributing molecular mechanisms. In rats, the regeneration progress was delayed and attenuated with PHx and bleeding and was not restored with colloid resuscitation. Livers restored their initial volume by postoperative day (POD) 2 after PHx through hepatocyte proliferation vs. POD 4 in the PHx and bleeding group, primarily by hepatocyte hypertrophy. With bleeding, hepatocyte proliferation was hindered in two mechanisms: by inhibiting cells from starting proliferation and by causing hindrance in G1/S progression. Liver hypoxia was prominent, with significant prolonged up-regulation of hypoxia-inducible factors (HIF) and HIF-targeted genes only in the PHx and bleeding group. Gene expression profiling revealed alterations in numerous genes that belong to critical pathways, including cell cycle, DNA replication, PI3K-Akt, purine, and pyrimidine metabolism. Because liver surgery is frequently performed in patients with a predamaged liver, an improper regenerative process after PHx and bleeding might lead to decompensation. The results hint at specific pathways to target in order to improve liver regeneration during PHx and bleeding.-Matot, I., Nachmansson, N., Duev, O., Schulz, S., Schroeder-Stein, K., Frede, S., Abramovitch, R. Impaired liver regeneration after hepatectomy and bleeding is associated with a shift from hepatocyte proliferation to hypertrophy.

Intraoperative factors associated with postoperative complications in body contouring surgery.

BACKGROUND: Several preoperative factors have been shown to influence outcome of body contouring surgeries. The effect of intraoperative features, including fluid volume administered, hemodynamic and respiratory parameters, and body temperature on postoperative complication, has not been reported to date. MATERIALS AND METHODS: All subsequent patients undergoing body contouring surgery in the Tel Aviv Medical Center between 2007 and 2012 were enrolled. Demographic and intraoperative data were collected and analyzed for possible associations with postoperative complications, including formation of seroma, hematoma/bleeding, other surgical site complications (infection, adhesiolysis, or need for debridement), formation of a hypertrophic scar, any documented, infection or a composite outcome of any of the previously mentioned. RESULTS: Data of 218 patients were assessed. Mean (standard deviation) age of patients was 41(14) y. Intraoperative administration of higher volumes of fluids was significantly associated with formation of seroma (P = 0.01), hematoma/bleeding (P = 0.03), hypertrophic scar (P = 0.01), surgical site complications (P = 0.01), and a composite outcome (P < 0.001). Development of hematoma/bleeding was associated with longer periods of low (<35.6°C) intraoperative core temperature (72% versus 50% of surgery duration in patients who did not develop this complication, P < 0.05). Surgical site complications were associated with longer periods of intraoperative oxygen desaturation (saturation ≤92%, 4.2% versus 0.9% of surgery duration in patients who did not develop surgical site complications, P < 0.01). CONCLUSIONS: Intraoperative moderate hypothermia, hypoxemia, and liberal fluid administration are associated with worse surgical outcome in patients undergoing body contouring surgery. Increased awareness of the potential adverse effects of these factors in body contouring surgery will enhance interventions aimed at avoiding and promptly treating such events.