Head, Neck, Maxillo-Facial And Dental Surgery
Elizabeth Combeer in The Final FRCA Short Answer Questions, 2019
Shared airway surgery, patient’s head distant to anaesthetist: Padding of eyes (extra care if exophthalmos).Secure taping of tube.Be alert to airway dislodgement or tube compression.Head-up tilt to improve venous drainage but not so as to impair arterial supply.Extensions on fluid administration set.Long breathing circuit for anaesthetic machine.
Static lung volumes and lung volume subdivisions
Jonathan Dakin, Mark Mottershaw, Elena Kourteli in Making Sense of Lung Function Tests, 2017
The test begins with a period of normal tidal breathing to establish a consistent end-expiratory volume (FRC), at which point the patient is connected to a closed circuit containing the test gas (Figure 7.2). This gas contains a known concentration of helium, along with sufficient oxygen for the test duration, with the balance made up of nitrogen. The breathing circuit also contains a carbon dioxide absorber such as soda lime to prevent the accumulation of carbon dioxide. Tidal breathing continues until the concentration of helium in the breathing circuit stabilises, indicating equilibration between lungs and the circuit, and relatively thorough mixing and even distribution throughout the lungs. The patient then performs a VC manoeuvre (full inspiration followed by full expiration, or vice versa) to complete the measurement.
Disconnection Monitors
Lara Wijayasiri, Kate McCombe, Paul Hatton, David Bogod in The Primary FRCA Structured Oral Examination Study Guide 1, 2017
What would be the potential consequences of a disconnection in the breathing circuit?If disconnection occurs in the presence of a trained, vigilant anaesthetist, then theoretically it should be identified rapidly with no significant consequences.However, if it takes longer to identify, then a spontaneously breathing patient would continue to breathe room air and over time would wake up (provided he or she were not receiving total intravenous anaesthesia).A ventilated patient, following a disconnection, would remain apnoeic, oxygen saturations would fall (the time at which this occurs would depend on the original FiO2 the patient was receiving), would become hypoxic and, if not corrected, there would be associated ECG changes (most likely bradycardia), hypotension and eventually the patient would suffer a cardiac arrest. Therefore, depending on the outcome of the disconnection, this event could be classified as a critical incident or a serious incident requiring investigation (SIRI).
Indications and clinical outcomes of fully covered self-expandable metallic tracheobronchial stents in patients with malignant airway diseases
Published in Expert Review of Respiratory Medicine, 2020
Muhammad Junaid Akram, Usman Khalid, Muhammad Abu Bakar, Mohammad Bilal Ashraf, Faheem Mehmood Butt, Faheem Khan
Once the lesion was found to be amenable for stenting, written informed consent was obtained and pre-procedure assessment by consultant anesthetist was conducted. The procedures have been performed by the experienced interventional pulmonologist through laryngeal mask airway (LMA) under general anesthesia by using intravenous propofol. Oxygen was given via anesthesia breathing circuit, and patient was kept on spontaneous ventilation while performing airways stenting. Once the bronchoscope was introduced via LMA and lesion located, a 0.035-inch diameter guide wire passed. The lesion was marked externally by using radiopaque clips under fluoroscopic guidance. After removing the scope the SEMS delivery system was advanced over the guide wire and through the lesion. The stent was deployed by retracting the introducer sheath under direct fluoroscopic guidance. Bronchoscopy was again performed to confirm stent deployment and positioning. The forceps was used to readjust the position of the stent if not appropriately placed.
Modeling the therapy system of noninvasive pressure support ventilation with the respiratory patient in COPD and ARDS
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Yueyang Yuan, Lixin Xie, Wei Liu, Zheng Dai
In order to testify the simulated results, as shown in Figure 5, a physical experimental platform was designed with using the active servo lung ASL5000 (IngMar medical, USA) and the NPSV respirator ST-30k (Hunan Micomme medical, China). In order to delivering the airflow from the respirator in to the lung, the NPSV respirator was connected to a head model through a standard breathing circuit (D2.0 cm × L180 cm internal diameter) and an oral-nasal mask Bestfit2 (Curative Medical Inc.). A homemade upper airway was placed in the head model for simulating human upper airway. And when the inhaled flow and the exhaled flow pass through the homemade upper airway, the resistances were, respectively, calibrated as ≈2.8 cmH2O s L−1 and ≈3.5 cmH2O s L−1. The homemade upper airway was connected to the ASL5000 by a breathing circuit (D2.0 cm × L70 internal diameter) for transporting the airflow into/ or out from the lung. This breathing circuit is in a standard size of. In the NPSV respirator and ASL5000, for carrying the physical experiments, the assigned ventilation parameters were nearly identical to the simulations as listed in Table 1. Due to homemade upper airway was applied, the set Rin = 21 cmH2O s L−1 and Rex = 23 cmH2O s L−1 for patient in COPD, and Rin = 11 cmH2O s L−1 and Rex = 16 cmH2O s L−1 for patient in ARDS.
Effects of occupational exposure to trace levels of halogenated anesthetics on the liver, kidney, and oxidative stress parameters in operating room personnel
Published in Toxin Reviews, 2020
Abbas Jafari, Fatemeh Jafari, Iraj Mohebbi
Several inhalational anesthetic agents are being used to induce and maintain anesthesia. Even in modern operating rooms (ORs), the trace levels of volatile anesthetics may leak from the breathing circuit and pollute the ambient air. Contamination of the OR environment occurs due to several reasons, including induction of anesthesia, pediatric anesthesia, exhalation of the patient, anesthesia machine leakage, inadequate scavenging system, and so on (Hoerauf et al.1996; Irwin et al.2009, Jafari et al.2018). Thus, OR personnel are unavoidably exposed to inhalational anesthetics that may lead to adverse health effects (Byhahn et al.2001, Irwin et al.2009). According to previous experimental studies, long-term exposure to anesthetic gases, especially halogenated agents (e.g. isoflurane, sevoflurane, enflurane, and methoxyflurane), can result in genotoxicity, neurotoxicity, spontaneous abortion, congenital malformations, as well as liver and kidney damage (McGregor 2000, Grasshoff and Antkowiak 2006, Rocha et al.2015, Zhu et al.2017). Although the exact mechanisms underlying these effects have not been elucidated, some researchers believe that anesthetic agents exert their adverse effect via inducing of oxidative stress (Malekirad et al.2005, Türkan et al.2005). Oxidative stress is defined as a marked imbalance between the production of reactive oxygen species (ROS) and antioxidant defense. Based on previous investigations, chronic exposure to anesthetic gases induces the ROS formation and oxidative damage to macromolecules (i.e. DNA, proteins, and lipids; Ranjbar et al.2007, Irwin et al.2009).
Related Knowledge Centers
- Carbon Dioxide
- Diethyl Ether
- Oxygen
- Hypercapnia
- Medical Device
- Inhalational Anesthetic
- Fresh Gas Flow
- Adjustable Pressure-Limiting Valve
- Schimmelbusch Mask
- Continuous Spontaneous Ventilation