Intraoperative mechanical power and postoperative pulmonary complications in low-risk surgical patients: a prospective observational cohort study.

BACKGROUND: Inadequate intraoperative mechanical ventilation (MV) can lead to ventilator-induced lung injury and increased risk for postoperative pulmonary complications (PPCs). Mechanical power (MP) was shown to be a valuable indicator for MV outcomes in critical care patients. The aim of this study is to assess the association between intraoperative MP in low-risk surgical patients undergoing general anesthesia and PPCs. METHODS: Two-hundred eighteen low-risk surgical patients undergoing general anesthesia for elective surgery were included in the study. Intraoperative mechanical ventilatory support parameters were collected for all patients. Postoperatively, patients were followed throughout their hospital stay and up to seven days post discharge for the occurrence of any PPCs. RESULTS: Out of 218 patients, 35% exhibited PPCs. The average body mass index, tidal volume per ideal body weight, peak inspiratory pressure, and MP were significantly higher in the patients with PPCs than in the patients without PPCs (30.3 ± 8.1 kg/m2 vs. 26.8 ± 4.9 kg.m2, p < 0.001; 9.1 ± 1.9 ml/kg vs. 8.6 ± 1.4 ml/kg, p = 0.02; 20 ± 4.9 cmH2O vs. 18 ± 3.7 cmH2O, p = 0.001; 12.9 ± 4.5 J/min vs. 11.1 ± 3.7 J/min, p = 0.002). A multivariable regression analysis revealed MP as the sole significant predictor for the risk of postoperative pulmonary complications [OR 1.1 (95% CI 1.0-1.2, p = 0.036]. CONCLUSIONS: High intraoperative mechanical power is a risk factor for developing postoperative pulmonary complications. Furthermore, intraoperative mechanical power is superior to other traditional mechanical ventilation variables in identifying surgical patients who are at risk for developing postoperative pulmonary complications. CLINICAL TRIAL REGISTRATION: NCT03551899; 24/02/2017.

Ratio of oxygen saturation index for predicting high-flow nasal cannula outcomes in emergency department for COVID-19 patients with severe hypoxemia: A retrospective study.

OBJECTIVES: High-flow nasal cannula (HFNC) oxygen therapy has been used as an initial ventilatory support for coronavirus disease 2019 (COVID-19) patients with mixed levels of acute hypoxemic respiratory failure (AHRF). However, the effectiveness of HFNC when used as initial ventilatory support in COVID-19 patients with severe AHRF exclusively is not well documented. Ratio of oxygen saturation (ROX) index (ROX = [SpO2/fraction of inspired oxygen]/respiratory rate) was shown to predict the outcome of HFNC in intensive care unit patients. Our study aimed to evaluate the utility of the ROX index for predicting HFNC therapy success/failure in COVID-19 patients with severe AHRF when HFNC is used as the first line of ventilatory support. METHODS: Retrospective study in 67 COVID-19 patients with severe AHRF receiving HFNC in the emergency department at a tertiary care academic medical center. ROX index was determined at 0, 2, 6, 12, and 24 h of HFNC onset. The need to escalate to noninvasive or invasive ventilatory support was documented. The receiver operating characteristic curves were performed and areas under the curves (AUCs) were calculated to evaluate the accuracy of ROX index for differentiating between patients who will succeed or fail HFNC therapy. RESULTS: HFNC therapy was successful in 19 patients (28.1%) and failed in 48 patients (71.6%). ROX index after 6 h of HFNC initiation had the best predictive capacity for the outcome of HFNC therapy (AUC = 0.78). ROX index >4.4 at 6 h of HFNC onset was significantly associated with HFNC success/failure. CONCLUSION: ROX index at 6 h after initiating HFNC therapy in COVID-19 patients with severe AHRF has a good predictive capacity for HFNC success/failure.

Harlequin syndrome during peripheral cardiopulmonary bypass in a patient with an obstructing tracheal schwannoma: A case report.

Surgical resection of obstructive tracheal tumors can be challenging to cardiothoracic surgeons and anesthesiologists. It is often difficult in these cases to maintain oxygenation by face mask ventilation during induction of general anesthesia. Also, the extent and location of these tracheal tumors can preclude conventional induction of general anesthesia and subsequent successful endotracheal intubation. Peripheral cardiopulmonary bypass (CPB) under local anesthesia and mild intravenous sedation may be safe to support the patient until securing a definitive airway. We describe a case of a 19-year-old female with a tracheal schwannoma, who developed differential hypoxemia (Harlequin, or North-South, syndrome) after institution of awake peripheral femorofemoral venoarterial (VA) partial CBP.

Respiratory Adverse Events After LMA® Mask Removal in Children: A Randomized Trial Comparing Propofol to Sevoflurane.

BACKGROUND: The removal of the laryngeal mask airway (LMA®) in children may be associated with respiratory adverse events. The rate of occurrence of these adverse events may be influenced by the type of anesthesia. Studies comparing total intravenous anesthesia (TIVA) with propofol and sevoflurane are limited with conflicting data whether propofol is associated with a lower incidence of respiratory events upon removal of LMA as compared to induction and maintenance with sevoflurane. We hypothesized that TIVA with propofol is superior to sevoflurane in providing optimal conditions and improved patient's safety during emergence. METHODS: In this prospective, randomized, double-blind clinical trial, children aged 6 months to 7 years old were enrolled in 1 of 2 groups: the TIVA group and the sevoflurane group. In both groups, patients were mechanically ventilated. At the end of the procedure, LMAs were removed when patients were physiologically and neurologically recovered to a degree to permit a safe, natural airway. The primary aim of this study was to compare the occurrence of at least 1 respiratory adverse event, the prevalence of individual respiratory adverse events, and the airway hyperreactivity score following emergence from anesthesia between the 2 groups. Secondary outcomes included ease of LMA insertion, quality of anesthesia during the maintenance phase, hemodynamic stability, time to LMA removal, and incidence of emergence agitation. RESULTS: Children receiving TIVA with propofol had a significantly lower incidence (10.8.% vs 36.2%; relative risk, 0.29; 95% CI [0.14-0.64]; P = .001) and lower severity ( P = .01) of respiratory adverse outcomes compared to the patients receiving inhalational anesthesia with sevoflurane. There were no statistically significant differences in secondary outcomes between the 2 groups, except for emergence agitation that occurred more frequently in patients receiving sevoflurane ( P < .001). CONCLUSIONS: Propofol induction and maintenance exerted a protective effect on healthy children with minimal risk factors for developing perioperative respiratory complications, as compared to sevoflurane.

Reduction of Nonoperative Time Using the Induction Room, Parallel Processing, and Sugammadex: A Randomized Clinical Trial.

BACKGROUND: An important variable in the operating room is the nonoperative time (NOT), the time between skin closure on a previous case and skin incision on the following case. Mismanagement of NOT can result in significant financial losses and delays in the operating room (OR) schedule, which can negatively impact efficiency and patient, surgeon, and staff satisfaction. NOT includes general anesthesia induction time (IT), emergence time (ET), and turnover time (TOT), and can be calculated by adding the 3 components. OR efficiency can be increased by applying parallel processing for general anesthesia induction and OR cleaning and reversal of neuromuscular blockade with sugammadex to reduce the 3 components of NOT without compromising patient safety. METHODS: This is a prospective, randomized study of 111 patients 18 to 75 years of age, American Society of Anesthesiologists (ASA) I-III, undergoing surgery requiring general anesthesia and muscle relaxation. Patients were randomly assigned to the control group (traditional linear processing for induction of anesthesia and OR cleaning and neuromuscular blockade reversal with neostigmine/glycopyrrolate) and the active group (parallel processing for induction of anesthesia and OR cleaning and neuromuscular blockade reversal with sugammadex). The primary outcome measured is the difference in the NOT. The secondary outcomes are surgeon and patient satisfaction. RESULTS: NOT was significantly shorter in patients who underwent the parallel processing strategy and received sugammadex compared to the patients in the control group (25.0 [18.0-44.0] vs 48.0 [40.0-64.5] minutes; Cliff' delta = 0.57; P < .001). After excluding the cases in the experimental group that were put into sleep in the OR (ie, the first case of the room), IT, ET, TOT, and NOT were further reduced and remained statistically significantly lower than the control group. Satisfaction scores from surgeons were significantly higher in the active group than in the control group (P < .001). There was no significant difference in the satisfaction scores of patients between the 2 groups. CONCLUSIONS: Our study showed that interventions, such as parallel processing during induction of anesthesia and room cleaning instead of linear processing and the use of the faster-acting sugammadex instead of the combination of neostigmine and glycopyrrolate for the reversal of rocuronium-induced neuromuscular blockade, resulted in shorter IT, ET, TOT, and therefore NOT, in addition to higher surgeon's satisfaction.

A sequential allocation study to determine the ED50 of Dexmedetomidine as an adjuvant to lidocaine intravenous regional anesthesia.

BACKGROUND: Intravenous regional anesthesia is an easy and reliable anesthetic technique, but its use is limited by tourniquet pain. Clonidine is effective in overcoming this shortcoming when used with intravenous regional anesthesia at a dose of 1 µg/kg. Dexmedetomidine has also been used successfully at a dose of 0.5 µg/kg. OBJECTIVE: Based on the potency ratios of clonidine and dexmedetomidine (8 to 1) we hypothesize that a lower dexmedetomidine dose would provide patients with 50 min of pain free tourniquet time. METHODS: After informed consent, patients received intravenous regional anesthesia with lidocaine and dexmedetomidine following a sequential allocation scheme. The first patient received a dose of 0.5 µg/kg of dexmedetomidine. The dose was then adjusted in 0.1 µg/kg gradients for the following patients depending on the success of the previous block. If a patient experienced tourniquet pain prior to 50 min, the next patient received a higher dose. If not, the dose was decreased. Recruitment continued until 6 independent crossovers were observed with a minimum of 20 patients. The median effective dose ED50 of dexmedetomidine was calculated using the modified up-and-down method. MAIN OUTCOME MEASURES: The median effective dose of dexmedetomidine (ED50) that provides 50 min of tolerance to the tourniquet during a lidocaine intravenous regional anesthesia by a sequential Dixon up-and-down allocation study. RESULTS: The ED50 of dexmedetomidine that provided 50 min of tolerance to the tourniquet was 0.30 ± 0.06 µg/kg. CONCLUSION: We determined that the dexmedetomidine dose necessary to provide 50 min of pain free tourniquet time during intravenous regional anesthesia was higher than expected based on the relative alpha-2 adrenergic receptor selectivity of dexmedetomidine compared to clonidine. TRIAL REGISTRATION: Clinicaltrials.gov: Retrospectively registered ( NCT05342870 ; registration date: 25/04/2022).

Propofol use in children: updates and controversies.

Advantages of propofol use in children may include less airway complications, less emergence agitation, and less postoperative behavioral changes. However, needle phobia and the complexity of total intravenous anesthesia set-up, as well as the pharmacokinetic and pharmacodynamic restrictions may limit the wide use of propofol-based anesthesia in the form of total intravenous anesthesia. Furthermore, pediatric infusion models and monitoring techniques are not fully validated yet. The choice of anesthesia type in children seems to be the result of a complex interplay between many factors related to the patient and the provider as well as logistic and operational factors that contribute to the decision-making process. Propofol has earned its place as a valuable choice in pediatric anesthesia. In addition, propofol and inhalation anesthesia should not be looked at as mutually exclusive; a combination of both may sometimes be the best approach to complex clinical dilemmas.

A New Index for Pre-Operative Cardiovascular Evaluation.

BACKGROUND: Currently used indices for pre-operative cardiovascular evaluation are either powerful, but complex, or simple, but with weak discriminatory power. OBJECTIVES: This study sought to prospectively derive and validate a simple powerful index that can stratify the cardiovascular risk of patients undergoing noncardiac surgery. METHODS: The derivation cohort consisted of 3,284 prospectively enrolled adult patients undergoing noncardiac surgery at the American University of Beirut Medical Center. The validation cohort consisted of 1,167,414 patients registered in the American College of Surgeons National Surgical Quality Improvement Program database. The primary outcome measure was death, myocardial infarction, or stroke at 30 days after surgery. RESULTS: The primary outcome occurred in 38 patients (1.2%) in the derivation cohort. Multivariate logistic regression analysis in the derivation cohort identified 6 data elements to be included in the prediction model: age ≥75 years, history of heart disease, symptoms of angina or dyspnea, hemoglobin <12 mg/dl, vascular surgery, and emergency surgery. Each patient was assigned a Cardiovascular Risk Index (CVRI) of 0, 1, 2, 3, and >3 based on the number of data elements present. The incidence of the primary outcome increased steadily across the CVRI groups in both the derivation (0%, 0.5%, 2.0%, 5.6%, and 15.7%, respectively; p < 0.0001) and validation (0.3%, 1.6%, 5.6%, 11.0%, and 17.5%, respectively; p < 0.0001) cohorts. The discriminatory power of the new CVRI was further confirmed by constructing a receiver-operating characteristic curve that had an area under the curve of 0.90 in the derivation cohort and 0.82 in the validation dataset. CONCLUSIONS: This study reports a new index for pre-operative cardiovascular evaluation which has a strong discriminatory power that can effectively stratify patients into low- (CVRI 0 to 1), intermediate- (CVRI 2 to 3), and high-risk (CVRI >3) groups. This has important implications for the efficient triage and management of patients scheduled for noncardiac surgery.

Fertility drugs and risk of ovarian cancer: dispelling the myth.

PURPOSE OF REVIEW: Worldwide 50-80 million people suffer from infertility. Assisted reproductive technology has provided a way of overcoming infertility and childlessness. The current article will focus on data linking infertility and its treatment to ovarian cancer. RECENT FINDINGS: Ovarian cancer risks associated with fertility drug treatment are encouraging, but not decisive. In view of the limited ability to evaluate drug effects on borderline tumors, given their rare occurrence, studies involving patient reports of prior drug exposures have noted an elevated risk of borderline tumors associated with fertility drugs. Nevertheless, the risk of invasive ovarian cancer appears to be restricted to those women who remain childless despite the infertility treatment. SUMMARY: As long as doubt persists, it might be advisable to reflect on a few clinical recommendations: identify high-risk infertile patients for ovarian cancer, investigate preexisting cancer before fertility treatment, inform patients regarding potential risks, obtain an informed consent, avoid exposure to long periods of ovulation induction cycles that are given before patients are referred for in-vitro fertilization and embryo transfer for women at greater risk and monitor women who have been treated with these drugs, especially those who failed to conceive, regularly and thoroughly.