Effect of Intraoperative High Positive End-Expiratory Pressure (PEEP) With Recruitment Maneuvers vs Low PEEP on Postoperative Pulmonary Complications in Obese Patients: A Randomized Clinical Trial.

Importance: An intraoperative higher level of positive end-expiratory positive pressure (PEEP) with alveolar recruitment maneuvers improves respiratory function in obese patients undergoing surgery, but the effect on clinical outcomes is uncertain. Objective: To determine whether a higher level of PEEP with alveolar recruitment maneuvers decreases postoperative pulmonary complications in obese patients undergoing surgery compared with a lower level of PEEP. Design, Setting, and Participants: Randomized clinical trial of 2013 adults with body mass indices of 35 or greater and substantial risk for postoperative pulmonary complications who were undergoing noncardiac, nonneurological surgery under general anesthesia. The trial was conducted at 77 sites in 23 countries from July 2014-February 2018; final follow-up: May 2018. Interventions: Patients were randomized to the high level of PEEP group (n = 989), consisting of a PEEP level of 12 cm H2O with alveolar recruitment maneuvers (a stepwise increase of tidal volume and eventually PEEP) or to the low level of PEEP group (n = 987), consisting of a PEEP level of 4 cm H2O. All patients received volume-controlled ventilation with a tidal volume of 7 mL/kg of predicted body weight. Main Outcomes and Measures: The primary outcome was a composite of pulmonary complications within the first 5 postoperative days, including respiratory failure, acute respiratory distress syndrome, bronchospasm, new pulmonary infiltrates, pulmonary infection, aspiration pneumonitis, pleural effusion, atelectasis, cardiopulmonary edema, and pneumothorax. Among the 9 prespecified secondary outcomes, 3 were intraoperative complications, including hypoxemia (oxygen desaturation with Spo2 ≤92% for >1 minute). Results: Among 2013 adults who were randomized, 1976 (98.2%) completed the trial (mean age, 48.8 years; 1381 [69.9%] women; 1778 [90.1%] underwent abdominal operations). In the intention-to-treat analysis, the primary outcome occurred in 211 of 989 patients (21.3%) in the high level of PEEP group compared with 233 of 987 patients (23.6%) in the low level of PEEP group (difference, -2.3% [95% CI, -5.9% to 1.4%]; risk ratio, 0.93 [95% CI, 0.83 to 1.04]; P = .23). Among the 9 prespecified secondary outcomes, 6 were not significantly different between the high and low level of PEEP groups, and 3 were significantly different, including fewer patients with hypoxemia (5.0% in the high level of PEEP group vs 13.6% in the low level of PEEP group; difference, -8.6% [95% CI, -11.1% to 6.1%]; P < .001). Conclusions and Relevance: Among obese patients undergoing surgery under general anesthesia, an intraoperative mechanical ventilation strategy with a higher level of PEEP and alveolar recruitment maneuvers, compared with a strategy with a lower level of PEEP, did not reduce postoperative pulmonary complications. Trial Registration: ClinicalTrials.gov Identifier: NCT02148692.

Intraoperative transfusion practices in Europe.

BACKGROUND: Transfusion of allogeneic blood influences outcome after surgery. Despite widespread availability of transfusion guidelines, transfusion practices might vary among physicians, departments, hospitals and countries. Our aim was to determine the amount of packed red blood cells (pRBC) and blood products transfused intraoperatively, and to describe factors determining transfusion throughout Europe. METHODS: We did a prospective observational cohort study enrolling 5803 patients in 126 European centres that received at least one pRBC unit intraoperatively, during a continuous three month period in 2013. RESULTS: The overall intraoperative transfusion rate was 1.8%; 59% of transfusions were at least partially initiated as a result of a physiological transfusion trigger- mostly because of hypotension (55.4%) and/or tachycardia (30.7%). Haemoglobin (Hb)- based transfusion trigger alone initiated only 8.5% of transfusions. The Hb concentration [mean (sd)] just before transfusion was 8.1 (1.7) g dl(-1) and increased to 9.8 (1.8) g dl(-1) after transfusion. The mean number of intraoperatively transfused pRBC units was 2.5 (2.7) units (median 2). CONCLUSION: Although European Society of Anaesthesiology transfusion guidelines are moderately implemented in Europe with respect to Hb threshold for transfusion (7-9 g dl(-1)), there is still an urgent need for further educational efforts that focus on the number of pRBC units to be transfused at this threshold. CLINICAL TRIAL REGISTRATION: NCT 01604083.

Perioperative acute kidney injury.

Perioperative acute kidney injury (AKI) is not uncommon and is associated with considerable morbidity and mortality. Recently, several definition systems for AKI were proposed, incorporating both small changes of serum creatinine and urinary output reduction as diagnostic criteria. Novel biomarkers are under investigation as fast and accurate predictors of AKI. Several special considerations regarding the risk of AKI are of note in the surgical patient. Co-morbidities are important risk factors for AKI. The surgery in itself, especially emergency and major surgery in the critically ill, is associated with a high incidence of AKI. Certain types of surgeries, such as cardiac and transplantation surgeries, require special attention because they carry higher risk of AKI. Nephrotoxic drugs, contrast dye, and diuretics are commonly used in the perioperative period and are responsible for a significant amount of in-hospital AKI. Before surgery, the anaesthetist is required to identify patients at risk of AKI, optimize anaemia, and treat hypovolaemia. During surgery, normovolaemia is of utmost importance. Additionally, the surgical and anaesthesia team is advised to use measures to reduce blood loss and avoid unnecessary blood transfusion. Hypotension should be avoided because even short periods of mean arterial pressure <55-60 mm Hg carry a risk of postoperative AKI. Higher blood pressures are probably required for hypertensive patients. Urine output can be reduced significantly during surgery and is unrelated to perioperative renal function. Thus, fluids should not be given in excess for the sole purpose of avoiding or treating oliguria. Use of hydroxyethyl starch needs to be reconsidered. Recent evidence indicates a beneficial effect of administering low-chloride solutions.

Impact of an interdisciplinary process to increase utilization of neuraxial anesthesia for cesarean delivery: A retrospective database analysis.

BACKGROUND: Neuraxial anesthesia is the preferred anesthesia mode for cesarean delivery (CD). The primary study aim was to study the rate of neuraxial anesthesia for cesarean delivery before and after educational strategies were implemented, focusing on neuraxial anesthesia use for CD. METHODS: We performed a retrospective analysis of the mode of anesthesia for CD. Educational strategies to inform about neuraxial anesthesia for CD included interdisciplinary daily handovers and ward rounds, and interdisciplinary academic meetings and simulation sessions. We retrieved data from the hospital electronic record for mode of anesthesia for CD, intravenous supplementation, to assess the impact of our strategies on neuraxial anesthesia use for CD (2014-2023). RESULTS: The rate of neuraxial anesthesia increased from 89.8% in 2014 to 96.3% in 2023, with corresponding decrease in general anesthesia from 10.2% to 4.5% for all CD. The use of labor epidural augmentation for unplanned CD increased from 31.9% to 55.1%. Intravenous supplementation with spinal anesthesia for unplanned CD increased from 18.1% to 32.1%. CONCLUSIONS: This study demonstrates the utility of educational strategies to increase neuraxial anesthesia use and highlights the importance of proactive interdisciplinary labor management.

Aged erythrocytes: a fine wine or sour grapes?

Blood transfusion saves many lives but carries significant risk of injury. Currently, red blood cell (RBC) concentrates can be stored up to 42 days. Concerns have recently been raised about the safety and efficacy of transfusing stored RBCs. Refrigerated storage results in a 'storage lesion' that is reflected by metabolic derangements, RBC shape modification, rheological changes, oxidative injury to lipids and proteins, alterations in oxygen affinity and delivery, increased adhesion of RBCs to endothelial cells, and accumulation of bioactive substances in storage media. In animal models, transfusion of aged, but not fresh, RBCs induces organ injury, inflammation, coagulopathy, and impaired oxygen delivery. A number of clinical studies, mostly observational or retrospective and from a single centre, have reported an association between transfusion of older RBCs and increased clinically significant outcomes, such as increased morbidity and mortality in certain patient populations, including trauma, critical care, and cardiac surgery. Others, however, have failed to indicate an influence of RBC age on outcome. The quality of evidence is currently too poor to make recommendations to change current transfusion practice; however, the transfusion community looks forward to the results of randomized trials currently addressing the long-standing question regarding the effects of RBC storage on clinically significant outcomes.

Prevalence of preoperative metabolic disturbances in elderly patients with hip fracture and their association with mortality - A retrospective cohort study.

STUDY OBJECTIVES: To assess the prevalence of preoperative acidosis and lactatemia in elderly patients having hip fracture surgery and their association with post-operative mortality. DESIGN: Retrospective cohort study. SETTING: Single tertiary medical center. PATIENTS: Patients ≥65 years having first traumatic hip fracture surgery between 2018 and 2021. MEASUREMENTS: 90-day postoperative mortality. MAIN RESULTS: In total, 1267 patients were included in the primary analysis (mean (SD) age 83(8) years; 802 (69%) females; median [Interquartile Range (IQR)] American Society of Anesthesiologists (ASA) physical score 3 [2,3]). Of these, 1227 were available for the multivariable analyses. Median [IQR] time from hospitalization to surgery was 28 [20, 42] hours. All-cause 90-day mortality rate was 9% (N = 114). The incidence of preoperative acidosis (pH < 7.35) and lactatemia (>1.2 mmol/L) was significantly higher among non-survivors. Mortality was highest in patients with both acidosis and lactatemia (19.1% compared to 4.4% among patients with neither). In a multivariable model, pH <7.35 and lactate >1.2 mmol/L remained independent predictors of 90-day mortality, with adjusted odds ratio (aOR) (95%CI) of 1.99 (1.31 to 3.04) and 2.32 (1.44 to 3.74), respectively, p = 0.001 for both. Time from hospitalization to surgery was not associated with mortality after adjustment for metabolic indices, aOR 1.00 (0.99, 1.00). CONCLUSIONS: Preoperative acidosis and lactatemia are common among patients ≥65 years having hip fracture surgery and are associated with 90-day all-cause mortality. Time from hospital admission to surgery is not an independent risk factor, once adjusted for metabolic indices. Future studies should evaluate whether the increased risk associated with preoperative metabolic disturbances is modifiable.

Increased dental trauma in children with attention deficit hyperactivity disorder treated with methylphenidate--a pilot study.

The purpose of this pilot study was to investigate the prevalence of trauma to incisor teeth in children with normal overjet and lip competence, treated with methylphenidate (Ritalin) for attention deficit hyperactivity disorder (ADHD). The study group consisted of 24 children (19 boys, 5 girls) aged 5-12 years (mean 8.45 +/- 2.25), diagnosed with ADHD and treated with methylphenidate at a minimal dosage of 10 mg per day. The control group consisted of 22 healthy children (13 boys, 9 girls) aged 5-12 years (mean 9.15 +/- 2.28). The dental examination included incisor relation measurements in the anterior segment (overjet), which was recorded using an orthodontic ruler. Lip competence was clinically determined, and anterior teeth were examined for dental trauma. The prevalence of dental trauma was significantly higher in the study group than in the control group (29.1% vs. 4.5% P = 0.02, t-test one tail). In conclusion, children with ADHD treated with methylphenidate have a high-risk for dental trauma. We believe that preventing dental trauma in this high risk group is possible. Consequently, the pediatrician and all medical staff attending to these children should encourage parents to consult frequently with a pediatric dentist to diagnose dental trauma and provide early treatment when needed.

Walking reduces the post-void residual volume in parturients with epidural analgesia for labor: a randomized-controlled study.

BACKGROUND: The post-void residual volume is higher among parturients who received epidural analgesia than those who received no or alternative analgesia. METHODS: This prospective, randomized, controlled, non-blinded study was performed in a tertiary referral center labor suite. The post-void residual volume was measured by a transabdominal ultrasound following a voiding attempt. Healthy parturients with low-dose epidural analgesia in active labor were randomized either to walk to the toilet or to use a bedpan for voiding. The primary outcome measure (post-void residual volume in labor) was compared between the study groups. RESULTS: The toilet group (n=34) and the bedpan group (n=28) demonstrated similar post-void residual volumes (212 +/- 100 vs. 168 +/- 93 ml, P=0.289). Twenty patients (59%) randomized to the toilet group were unable to walk and actually voided in a bedpan. A secondary analysis was performed analyzing the groups as treated. The post-void residual volume was significantly lower in the actual toilet group (n=14, 63 +/- 24 ml) vs. the bedpan group (n=48, 229 +/- 200 ml), P=0.0052. Thirteen (93%) women who walked to the toilet managed to void before the ultrasound measurement vs. 20/48 (42%) using the bedpan, P=0.001. Fewer women who managed to walk to the toilet required urinary bladder catheterization during the labor than women who used the bedpan (6/14, 43% vs. 36/48, 75%) P=0.028. CONCLUSION: Women who were randomized to walk to the bathroom with epidural analgesia and were able to do so during labor had a significantly reduced post-void residual volume and a reduced requirement for urinary catheterization.

Labor epidural analgesia onset time and subsequent analgesic requirements: a prospective observational single-center cohort study.

BACKGROUND: We investigated the correlation between lumbar epidural analgesia onset time and pain intensity at 60 and 120 min after initiation. METHODS: We conducted a prospective observational study of nulliparous women receiving lumbar epidural analgesia (initial bolus 15 mL bupivacaine 0.1% with fentanyl 3.33 µg/mL), followed by patient-controlled epidural analgesia (PCEA). The measured variable was lumbar epidural analgesia onset time (time to pain numerical rating score ≤3). Secondary outcomes were pain score at 60 and 120 min and at full dilatation; and analgesic requirements through the labor. RESULTS: One-hundred-and-five women were eligible for analysis. There was a significant correlation between lumbar epidural analgesia onset time and pain intensity at 60 min (Spearman's R2=0.286, P=0.003), but not at 120 min (R2=0.030, P=0.76). Women who requested more PCEA boluses during the first 120 min had a longer lumbar epidural analgesia onset time (R2=0.321, P=0.001) and reported higher pain scores at 60 min (R2=0.588, P <0.001) and at 120 min (R2=0.539, P <0.001). Women who reported higher pain scores at 60 min had more pain at 120 min (R2=0.47, P <0.001) and higher analgesic consumption during labor (R2=0.403, P <0.001). Women who were at a greater cervical dilatation at 60 and 120 min had higher pain scores at the same time point (R2=0.259, P=0.008 and R2=0.243, P=0.013 respectively). CONCLUSION: There was a correlation between the onset time of lumbar epidural analgesia during labor and the pain score 60 min later but this had disappeared by 120 min.

Neuraxial block for delivery among women with low platelet counts: a retrospective analysis.

BACKGROUND: Laboring women with low platelet counts may be denied neuraxial block due to concerns about causing a spinal-epidural hematoma. AIMS: To assess the anesthetic management, complications and outcome variables of women with low platelet counts, and to expand the existing data regarding the safety of neuraxial blocks in this patient population. METHODS: This is a retrospective analysis of anesthetic and obstetric data from women with platelet counts <100 000/µL, who were admitted to a single referral center during 2011-2014. The rate of neuraxial block and related complications were examined in relation to the platelet count and the results combined with published data to assess the risk of spinal-epidural hematoma. RESULTS: During the study period, 471 of 45 462 women (1%) had a low platelet count (<100 000/µL). The rate of neuraxial block was significantly higher in women with platelet counts of 70-99 000/µL (280/394, 71.1%) when compared to women with platelet counts of 50-69 000/µL and 0 to 49 000/µL (23/59, 38.9% and 5/18, 27.8%, respectively, P <0.0001). Women in the lower platelet count ranges had a higher risk of cesarean delivery under general anesthesia and longer hospital stay. No neuraxial hematoma were reported. CONCLUSIONS: This study contributes a substantial series of neuraxial blocks among women with low platelet counts. The findings support that the risk of hematoma is low if the platelet count is <100 000/µL, specifically between 70 and 99 000/µL. Risk assessment in the lower count ranges requires a much larger sample.

Uncomplicated general anesthesia in the elderly results in cognitive decline: does cognitive decline predict morbidity and mortality?

Elderly surgical patients constitute a unique surgical group. They require special consideration in order to preempt the long term adverse effects of anesthesia. This paper examines the proposition that general anesthesia causes harm to elderly patients with its impact being felt long after the anesthetic agents are cleared from the body. One complication, Postoperative Cognitive Decline (POCD), is associated with the administration of anesthesia and deep sedation. Its' occurrence may herald an increase in morbidity and mortality. Based on both human and animal data, this paper outlines a unitary theoretical framework to explain these phenomena. If this hypothesis proves to be correct, anesthesiologist should consider regional rather than general anesthesia for equivalent surgical procedures to reduce POCD and consequently achieving superior patient outcome.

Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients (PROBESE): study protocol for a randomized controlled trial.

BACKGROUND: Postoperative pulmonary complications (PPCs) increase the morbidity and mortality of surgery in obese patients. High levels of positive end-expiratory pressure (PEEP) with lung recruitment maneuvers may improve intraoperative respiratory function, but they can also compromise hemodynamics, and the effects on PPCs are uncertain. We hypothesized that intraoperative mechanical ventilation using high PEEP with periodic recruitment maneuvers, as compared with low PEEP without recruitment maneuvers, prevents PPCs in obese patients. METHODS/DESIGN: The PRotective Ventilation with Higher versus Lower PEEP during General Anesthesia for Surgery in OBESE Patients (PROBESE) study is a multicenter, two-arm, international randomized controlled trial. In total, 2013 obese patients with body mass index ≥35 kg/m2 scheduled for at least 2 h of surgery under general anesthesia and at intermediate to high risk for PPCs will be included. Patients are ventilated intraoperatively with a low tidal volume of 7 ml/kg (predicted body weight) and randomly assigned to PEEP of 12 cmH2O with lung recruitment maneuvers (high PEEP) or PEEP of 4 cmH2O without recruitment maneuvers (low PEEP). The occurrence of PPCs will be recorded as collapsed composite of single adverse pulmonary events and represents the primary endpoint. DISCUSSION: To our knowledge, the PROBESE trial is the first multicenter, international randomized controlled trial to compare the effects of two different levels of intraoperative PEEP during protective low tidal volume ventilation on PPCs in obese patients. The results of the PROBESE trial will support anesthesiologists in their decision to choose a certain PEEP level during general anesthesia for surgery in obese patients in an attempt to prevent PPCs. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02148692. Registered on 23 May 2014; last updated 7 June 2016.

Holy consent--a dilemma for medical staff when maternal consent is withheld for emergency caesarean section.

A parturient (grand multipara) developed arrested labour complicated by severe fetal heart rate decelerations. Senior physicians explained the need for a caesarean section, but she chose to deliver vaginally since rabbinical blessing could not be obtained. Forcing the mother to have a cesarean section without consent is considered "civil battery." The dilemma faced by medical staff and the implications of her refusal for the treating medical staff are described.

Myocardial ischemia in sedated patients undergoing fiberoptic bronchoscopy.

STUDY OBJECTIVE: To study the incidence of myocardial ischemia and related hemodynamic alterations in sedated patients undergoing fiberoptic bronchoscopy (FOB). DESIGN: Prospective study. SETTING: Tertiary care, university hospital. PATIENTS: Twenty-nine patients, age 50 years or older, undergoing elective FOB. INTERVENTIONS: Myocardial ischemia was assessed by continuous ECG monitoring beginning 30 min before, and until 2 h after FOB. MEASUREMENTS AND RESULTS: During FOB, there was a significant rise in heart rate (89+/-3 [mean+/-SE] to 120+/-4 beats/min) and fall in oxygen saturation (95+/-1 to 90+/-1%). There was no significant rise in systolic or diastolic BP. Five patients (17%) had myocardial ischemia during FOB that lasted 20+/-8 min. Their demographic and pre-FOB characteristics were not different from the other patients. Compared to baseline values, a significant rise in heart rate, a fall in oxygen saturation, and no significant change in BP were observed during FOB in patients, both with or without ischemia. Although not statistically significant, ischemia was associated with more protracted procedures. CONCLUSIONS: Myocardial ischemia may develop in elderly patients undergoing FOB. This observation encourages the routine use of ECG and oximetry during FOB, allowing for early intervention to prevent the dangerous combination of hypoxia, tachycardia, and myocardial ischemia. Moreover, this study suggests that methods to ensure oxygenation during FOB should be adhered to, and that the routine administration of atropine should be reconsidered.

Coronary spasm during outpatient fiberoptic laser bronchoscopy.

A 63-year-old woman with metastatic breast cancer was referred to our bronchoscopy unit for outpatient laser resection of an endobronchial mass through fiberoptic bronchoscopy. The patient had no history of ischemic heart disease. During the procedure, the patient developed an ST-segment elevation and a complete atrioventricular block. IV nitroglycerin and morphine were effective in treating this episode. In this patient, we were able to demonstrate a focal spasm by postbronchoscopy coronary angiography.

Blast lung injury from an explosion on a civilian bus.

OBJECTIVE: To assess clinical signs and management of primary blast lung injury (BLI) from explosions in an enclosed space and to propose a BLI severity scoring system. DESIGN: Retrospective analysis. PATIENTS: Fifteen patients with primary BLI resulting from explosions on two civilian buses in 1996. RESULTS: Ten patients were extremely hypoxemic on admission (PaO2 < 65 mm Hg with oxygen supplementation). Four patients remained severely hypoxemic (PaO2/fraction of inspired oxygen (FIO2) ratio of < 60 mm Hg) after mechanical ventilation was established and pneumothoraces were drained. Initial chest radiographs revealed bilateral lung opacities of various sizes in 12 patients (80%). Seven patients (47%) had bilateral pneumothoraces and two patients had a unilateral pneumothorax. Five (33%) had clinically significant bronchopleural fistulae. After clinical and laboratory data were collected, a BLI severity score was defined based on hypoxemia (PaO2/FIO2 ratio), chest radiographic abnormalities, and barotrauma. Severe BLI was defined as a PaO2/FIO2 ratio of < 60 mm Hg, bilateral lung infiltrates, and bronchopleural fistula; moderate BLI as a PaO2/FIO2 ratio of 60 to 200 mm Hg and diffuse (bilateral/unilateral) lung infiltrates with or without pneumothorax; and mild BLI as a PaO2/FIO2 ratio of > 200, localized lung infiltrates, and no pneumothorax. Five patients developed ARDS with Murray scores > 2.5. Respiratory management included positive pressure ventilation in the majority of the patients and unconventional methods (ie, high-frequency jet ventilation, independent lung ventilation, nitric oxide, and extracorporeal membrane oxygenation) in patients with severe BLI. Of the four patients who had severe BLI, three died. All six patients with moderate BLI survived, and four of five with mild BLI survived (one with head injury died). CONCLUSIONS: BLI can cause severe hypoxemia, which can be improved significantly with aggressive treatment. The lung damage may be accurately estimated in the early hours after injury. The BLI severity score may be helpful in determining patient management and prediction of final outcome.

Sedation in outpatient bronchoscopy.

Bronchoscopy is a procedure that is likely to provoke anxiety as the patient is surrounded by monitoring and bronchoscopy equipment, and care is administered by strangers who perform intimate, invasive, and sometimes, painful procedures. Sedation is needed, therefore, to allay anxiety and reduce stress, improve patient comfort and co-operation, provide amnesia and facilitate the bronchoscopic procedure. In this review we try to summarize the current knowledge on currently used sedation protocols with special reference to the commonly used pharmacological agents. We believe sedation should be used routinely in fiberoptic bronchoscopy in order to achieve a safe and pleasant procedure for both the patient and the pulmonologist.

Asymptomatic vallecular cyst: airway management considerations.

Airway problems are easiest to manage when they are anticipated. Difficult intubation might, however, occur in patients with no obvious signs or symptoms suggesting airway difficulty. We describe a case where laryngeal inlet was obscured by a large vallecular cyst that was discovered during rapid-sequence induction of general anesthesia, causing difficulty in tracheal intubation. Once the patient was allowed to recover from general anesthesia, the trachea could be safely intubated using a fiberoptic bronchoscope.

[Pulmonary thrombo-endarterectomy].

Chronic pulmonary thromboembolism is an underdiagnosed condition with major morbidity and mortality. Over the past year and a half, we diagnosed 6 new cases of which 3 underwent successful, pulmonary thrombo-endarterectomy (2 in San Diego, 1 in Jerusalem). All recovered fully and returned to normal, active life. We conclude that pulmonary thrombo-endarterectomy is a viable option for patients with chronic pulmonary thromboembolism.