Back To Search Results

Airway for Laser Surgery

Editor: Ly Vu Updated: 10/20/2022 5:59:35 PM

Introduction

Medical lasers are used in procedures in various specialties, including otolaryngology, ophthalmology, dermatology, plastic surgery, and dental surgeries, as well as in intraabdominal, cardiothoracic, neurologic, gynecologic, and urologic procedures. Lasers provide a source of focused, coherent light capable of transmitting intense energy to a precise location. Each laser type acts upon a specific chromophore that preferentially absorbs the laser light resulting in heat and eventually in the destruction and cauterization of the tissue. Importantly, lasers can ignite flammable materials present in the operating field, such as endotracheal tubes, sponges, and catheters. Such foreign materials may themselves absorb the laser energy and ignite, or a spark can be created from the laser cauterization that then spreads to the combustible foreign material. Lasers also pose a risk of eye injury (both to the patient and operating room personnel), laser plume, electrical tripping, and release of chemical contaminants.

Using a laser in upper aerodigestive surgery introduces a source of ignition that is especially dangerous when supplemental oxygen is added to the inspiratory gas mixture. This dilemma is constantly discussed, and multiple techniques have been developed to provide ventilation to an anesthetized patient while keeping the surgical field maximally accessible and minimizing laser-related hazards. The common ventilatory strategies include conventional endotracheal intubation, jet ventilation, intermittent apnea technique, and spontaneous breathing.[1] Multiple methods and numerous "laser-resistant" endotracheal tubes (ETT) were designed to protect the operating field from the hazards of medical lasers. The American Society of Anesthesiologists now recommends these as the default endotracheal airway during laser surgery of the respiratory tract.[2] The cuff is the most vulnerable part of the ETT. During intubation, once the tube passes through the vocal cords, the balloon at its distal end (cuff) is inflated with air (or saline) to occlude the trachea external to the tube and thus directs all the gas flows from the ETT exclusively to the trachea, and vice versa. A dye such as methylene blue is typically instilled into the cuff for such cases, so there is an obvious visual alert if the balloon is inadvertently popped. If the cuff is damaged by a laser (or other instruments or the patient's dentition), it becomes compromised and can no longer seal the trachea. This leads to a gas mixture rich in oxygen that can escape to the upper airway and surgical field. A fire may be ignited during this event or subsequent use of the laser. The ETT and other materials potentially present in the field, such as gauze and surgical drapes, are the most common fuels for an airway fire.[3]

Anatomy and Physiology

Register For Free And Read The Full Article
Get the answers you need instantly with the StatPearls Clinical Decision Support tool. StatPearls spent the last decade developing the largest and most updated Point-of Care resource ever developed. Earn CME/CE by searching and reading articles.
  • Dropdown arrow Search engine and full access to all medical articles
  • Dropdown arrow 10 free questions in your specialty
  • Dropdown arrow Free CME/CE Activities
  • Dropdown arrow Free daily question in your email
  • Dropdown arrow Save favorite articles to your dashboard
  • Dropdown arrow Emails offering discounts

Learn more about a Subscription to StatPearls Point-of-Care

Anatomy and Physiology

Upper airway manipulations are very stimulating and often cannot be effectively performed on an awake patient. Once anesthetized, the patient cannot adequately protect their airway from aspiration and obstruction since the oropharyngeal muscle tone, expiration reflex, coughing reflex, and apnea reflex are progressively obtunded by the majority of general anesthetics.[4][5][6] Changes in the respiratory pattern invariably and progressively lead to hypoventilation and then to apnea. This introduces a need for endotracheal intubation to facilitate ventilation of the lungs and to prevent the possibility of airway obstruction and asphyxiation. An endotracheal tube with an inflated cuff effectively occludes the portion of the trachea outside of the hollow plastic tube itself, performing the above-described functions. Yet, in the case of upper airway surgery, it can also obstruct the surgical field and be vulnerable to mechanical damage from surgical manipulations, including using a laser.

Smaller-sized devices, like jet ventilation catheters, can be placed below vocal cords to insufflate oxygen, provide some ventilatory oscillations, and simultaneously allow for better visualization of the surgical field.[7] Nonetheless, they cannot completely replace the respiratory function nor protect the distal airway from aspiration or generated air contaminants and chemical hazards inherent to laser surgery. The airway may be left unprotected with intermittent mask ventilation between the periods of surgical manipulation, which provides for an unobstructed operative field. This approach is suitable for short procedures with little risk of bleeding in patients able to tolerate periods of apnea but carries the risk of laryngospasm, aspiration, and loss of control over the airway is significant and may preclude the use of this technique for many laser airway surgeries. Alternatively, the patient can be breathing spontaneously through the procedure, but this introduces a mobile surgical field and risks of plumes and anesthetic gasses inhalation by the patient and operating room personnel.[3]

Indications

If laser airway surgery is planned, intubation should be performed with designated "laser-safe" endotracheal tubes. This "laser-safe" name is a misnomer, as airway fire is still possible with these devices, but they have been designed with additional safety features such as dye-filled supplementary cuffs and are constructed of less-flammable materials such as metal.[8] Apneic techniques, spontaneous ventilation, and alternative airway devices such as laryngeal mask airways (LMAs) or jet ventilation are possible though used very infrequently in laser airway surgery for access and control reasons. A secured airway, with a specially designed tube and a team familiar with specific challenges and risks of laser airway surgery, is always the safest option.[9][10]

Contraindications

There are no absolute contraindications to using specialized endotracheal tubes to secure the airway apart from allergies to the tube material if airway surgery is required. If the patient is not healthy enough to tolerate a necessary airway surgery, alternatives such as tracheostomy should be considered.

Equipment

Commonly Used Lasers

Carbon dioxide (CO2) lasers are historically the most commonly used lasers in otolaryngologic surgery. The infrared light produced is not visible to humans at 10,600 nm and produces intense thermal injury as its chromophore is water.[11] It is necessary to use a visible-light aiming beam and to ensure this aiming beam is accurate to the invisible laser before beginning the operation. Eyes (of both the patient and the OR personnel) are especially vulnerable to the CO2 laser, though simple, clear glass or plastic is sufficient for protection.[12]

Specifications of these and other commonly used lasers (KTP, Ho:YAG, Nd:YAG, Argon, pulsed dye) are discussed elsewhere in StatPearls and are beyond the scope of this review.

Numerous endotracheal tubes were designed to withstand laser damage, maintain the integrity of their components, and minimize the risk of airway fire. Please refer to the individual product data sheets before using any new endotracheal airway tube. Below are a few examples of the most common designs of laser-resistant tubes.

  • Soft and flexible white rubber tubes covered with copper foil (eg, Rusch Lasertubus) are resistant to CO2, Nd/YAG, and Argon lasers. These are most often double-cuffed for additional protection.
  • Silicone-made tubes wrapped in aluminum foil (eg, Laser shield by Xomed ) resist CO2 and potassium titanyl phosphate (KTP) lasers.
  • Stainless steel corrugated spiral ETTs (eg, Mallinckrodt Laser Flex) are suitable for CO2 and KTP lasers. The metal core is non-flammable and kink-resistant. The risk of reflecting a laser beam is very low, yet the metal may conduct heat to surrounding tissues and materials.
  • Red rubber tubes, especially if wrapped with aluminum or copper foil (eg, Sheridan Laser-Trach), have a long-standing record of safe use with CO2 and KTP lasers but have been largely supplanted by the products above.

Many of these tubes have 2 cuffs, and current American Society of Anesthesiologists guidelines recommend these to be filled with saline, as this conveys additional protection against fire in case the laser beams pop the cuff. Adding methylene blue (or other biocompatible dye) to the saline in the cuff balloon can aid in detecting cuff perforation.[2] The surgical team should use flame-resistant surgical drapes if possible, though covering exposed skin with saline-soaked sterile towels is far more common and is effective.

Personnel present in the room must wear wavelength-specific protective eyeglasses to prevent possible laser radiation exposure and irreparable corneal or retinal injury, and signage indicating laser use should be placed on the outer face of all doors to the operating room. In general, clear glass or plastic goggles are used when working with a CO2 laser; amber or orange filters for KTP and argon lasers; green or clear filters for Nd:YAG; blue for dye lasers.[13] High-efficiency masks should be used to protect the staff from smoke plumes. These result from tissue vaporization and contain fine microparticles (mean size 0.3 micrometers) capable of depositing in the lower airways and alveoli, potentially posing risks of affecting mucociliary clearance, interstitial pneumonitis, bronchiolitis, and mutagenicity. This is of particular concern when treating papillomatous disease, as there is a hypothetical risk of seeding papilloma.[14] Plume scavenging systems should be employed because the commonly used general room ventilation (aka "dilution ventilation") is insufficient to remove air contaminants. Room suction hose nozzle inlet may be used as well and must be kept within two inches of the operative field to effectively evacuate airborne contaminants generated by laser devices.[15]

Personnel

In addition to the standard operating room setup of a surgeon, anesthetist, scrub nurse, and circulating nurse, an additional staff member is tasked with operating the laser itself. All personnel should be appropriately trained in laser safety and equipped with wavelength-specific protective equipment.

Preparation

Appropriate airway equipment chosen in accordance with the airway management plan must be present in the room (laser-resistant ETT, jet ventilator). Personnel in the room where the laser energy source is applied must wear protective eyewear and filtering masks. In the event an airway fire occurs, syringes with saline can be premade and used for extinguishing.

Technique or Treatment

Endotracheal Intubation for Laser Surgery

Endotracheal intubation with a cuffed ETT establishes a secure, monitored, and controlled airway, allowing for positive pressure ventilation with effective delivery of respiratory gas mixture and inhalational anesthetic. However, an ideal ETT that does not ignite and has a design resembling conventional endotracheal tubes does not exist. The laser-resistant ETTs are commercially available and provide significantly superior protection against ignition compared to conventional polyvinyl chloride endotracheal tubes. These are most commonly used for laser surgery of the airway. Standard endotracheal intubation techniques apply when positioning these devices.  

Typically, the smallest acceptable ETT is chosen to maximize the exposure of the surgical field. The tracheal cuff of the laser tube (or both cuffs if dual-cuffed) is filled with normal saline mixed with a biological dye (eg, methylene blue). This will decrease the risk of ignition and serve as an indicator of cuff rupture if such occurs. The time to full inflation of the cuff may be prolonged when liquid is used as a filler, but this is rarely of clinical significance. The anesthesiologist should then minimize the delivered oxygen concentration to the smallest required concentration, avoid using nitrous oxide, and allow a few minutes for highly concentrated oxidizer gases to disperse before approving the activation of the laser.[2] The surgeon may request to temporarily deflate the cuff or even remove (and then re-insert) the tube under the direct laryngoscopic view to gain access to structures obscured by the ETT. The anesthesiologist should have a spare endotracheal airway device ready (typically an endotracheal tube of the same or smaller size) in case the existing ETT is damaged by the laser or other manipulation.

Jet Ventilation

Jet ventilation utilizes a high-pressure stream of gas delivered into the upper airway. This reduces the degree of stimulation and provides for the minimally obstructed surgical view yet yields no protection to the airway. Respiratory gas is being actively insufflated either supraglottically (via the aligned rigid bronchoscope with jet ventilator adapter positioned above the open vocal cords), transglottically (via a small-caliber transglottic catheter passed below the vocal cords), or using transtracheal approach (for patients with predicted difficult intubation or as a rescue airway utilizing a cricothyroid cannula). The last two methods help push blood and debris out of the trachea with the expiratory flow of gas. During manual jet ventilation, an injector connected to the gas supply insufflates the respiratory mixture into the trachea, but the removal of gas depends on passive exhalation and requires a patent upper airway and adequate time between jet insufflations to avoid barotrauma. The reducing valve provides the inflow pressures of 1 to 4 atmospheres.

Alveolar oxygen delivery and carbon dioxide removal mostly depend on diffusion to and from the bronchial tree, as there are only small changes in lung volumes during manual jet ventilation. Thus any small-diameter upper airway stenosis that impairs the inflow/outflow of gas creates a risk of air-trapping. Another modality, high-frequency jet ventilation, relies on delivering very small tidal volumes at very high respiratory rates (100 to 150 times a minute) to augment diffusion efficacy. Specialized equipment, properly trained personnel, and an intravenous anesthetic delivery technique (as compared to the inhalational route) are needed, as well as a blood gas monitoring must be established if the procedure is planned to be for an extended time, as inadequate gas exchange (hypoxemia, hypercarbia) is a common consequence. Mucosal dehydration, stomach insufflation, laser burn to the trachea (if no cuff was present to protect areas distal to laser application), pneumothorax, and pneumomediastinum are other possible complications of this technique.[16][17]

Intermittent Apnea Technique

The patient is intubated and extubated intermittently with the airway exposed using the suspension laryngoscopy. When intubated, the patient is hyperventilating, and the ETT is removed to allow for a period of apnea and laser application. The duration of apnea is individually determined, guided by pulse oximetry and end-tidal carbon dioxide values. In general, periods of apnea up to 5 min are allowed, assuming oxygen saturation and end-tidal carbon dioxide (EtCO2) levels remain reasonable (eg, SpOabove 90% and EtCO2 between 40 and 60 mm Hg.). The addition of continuous respiratory gas delivery via a high-flow nasal cannula may further increase the apneic period.[18][19] Inhalational anesthetics cannot be delivered constantly using this method; thus, total intravenous anesthesia is preferred. This technique is more common in pediatric ENT surgery: although laser-resistant ETTs with small internal diameters are available, their outer diameter is still larger due to the presence of additional insulation layers, thus interfering with the space available in the pediatric airway. Aspiration, laryngospasm, and loss of airway are the feared, yet infrequent, complications of technique.[3][20][21]

Spontaneous Ventilation Technique

The patient is anesthetized, maintaining spontaneous ventilation, and an oxygen-enriched gas is delivered through a side port of the operating laryngoscope or a catheter. Ventilation cannot be assisted. Inhalational anesthetics are best avoided since these will invariably escape into the operating room environment. This technique offers unobstructed access to the larynx, but there is a moving surgical field since muscle relaxants cannot be used. It also provides no protection from pulmonary aspiration or laryngospasm nor prevents pollution of the operating room environment with anesthetic gases and laser plumes.

Complications

The complications inherent to medical laser procedures are surgical fire, iatrogenic burns to surrounding tissues, and ocular injury.[22]

Risk of fire: Following electrosurgical devices, surgical lasers are considered the second most common source of operating room fires.[23] Surgeries of the pharynx, larynx, and trachea are the most at-risk procedures, respectively.

If an airway fire occurs:

  • Remove the fuel source (immediately remove the ETT and other burning fragments).
  • Remove the source of ignition (stop the laser).
  • Eliminate the oxidizer flow (disconnect the circuit, and stop ventilation and the delivery of gasses).
  • Extinguish the remaining fire, if any, with saline.
  • Continue anesthesia (via intravenous route).
  • Mask ventilated with 100% FiO2.
  • Perform direct/video laryngoscopy or bronchoscopy to assess the damage and remove debris. Bronchial lavage may be needed to wash out fragments.
  • Re-establish the airway (eg, re-intubate, place a laryngeal mask).
  • Assess for damage to the oropharynx and face.
  • Consider intensive care unit admission and tracheostomy if needed.[2]

Risk of Iatrogenic Burns

Burns can occur in addition to airway fires, due to accidental exposure of tissues to laser or from the reflection of the laser beam from reflective surfaces in the operative field. The presence of a cuffed ETT limits the possibility of the beam reaching the distal trachea and airway without rupturing the cuff balloon first. Applying saline-soaked gauze to the mucosal areas adjacent to the surgery site is an effective way to prevent such collateral damage.

Ocular Injury

Ocular injuries result from the direct exposure of the eye to the laser or a reflection of the beam. Depending on the physical properties of the laser, several structures can be affected, yet the most commonly involved are the cornea (water-rich) and retina (pigment-rich). Personnel outside the operating room must be warned of using a laser via appropriate signage on the outer surface of all doors to the laser operating room. Any windows in the laser operating room should be covered with opaque coverings. The risk of ocular injury can be significantly decreased by using wavelength-specific filters on safety glasses worn by the patient and operating room personnel.[24] Laser eye injuries are considered an emergency as they can cause permanent blindness. Symptoms include a sensation of a bright flash of colored light and, sometimes, a popping sound matching with the activation of the laser, followed by the loss of visual acuity and the presence of floaters in the visual field.[25] Other laser hazards, like laser plumes, have been shown to have cancerogenic potential. These can be mitigated by using plume scavenging systems and personal high-efficiency filtering masks.[26]

Clinical Significance

Maintenance of the patient's airway and adequate ventilation during upper respiratory tract surgery can be difficult due to the need to maintain an unobstructed view of the operative field. This is usually achieved using a smaller specialized (laser-resistant) ETT, jet ventilation devices, and intermittent or spontaneous ventilation techniques. The use of medical lasers is also complicated by the risk of surgical fire in an oxidizer-rich (oxygen, nitrous oxide) environment. Numerous recommendations exist, and comprehensive guidelines must be followed to minimize the risks inherent to these types of surgeries.

Enhancing Healthcare Team Outcomes

Every healthcare team member must take precautions during laser surgery of the upper airway to avoid harm to themself, the patient, or other operating room personnel. Wear proper protective equipment, which includes a high-efficiency mask and wavelength-specific protective eyeglasses.

To decrease the risk of airway fire:

  • Use the lowest concentration of oxygen possible
  • Avoid using nitrous oxide as an anesthetic (at high temperatures, it can release oxygen and act as an oxidizer)
  • Limit laser use to short pulses and the lowest power
  • Activate the laser only when the tip of the laser source is visible, and the endotracheal tube is out of reach of the source.
  • Cover the patient's face and chest with wet towels, and protect the eyes with wavelength-specific eye protection
  • Have saline-filled large (eg, 50 mL) syringes within reach during procedures with a high risk of ignition
  • Know the nearest location of a fire extinguisher and a water source

References


[1]

Inglis D, Gilhooly M, Patel A. The simultaneous use of three ventilatory techniques to maintain oxygenation in a patient undergoing tracheal laser resection of tumour. Anaesthesia reports. 2019 Jul-Dec:7(2):70-72. doi: 10.1002/anr3.12021. Epub 2019 Aug 12     [PubMed PMID: 32051954]


[2]

Apfelbaum JL, Caplan RA, Barker SJ, Connis RT, Cowles C, Ehrenwerth J, Nickinovich DG, Pritchard D, Roberson DW, Caplan RA, Barker SJ, Connis RT, Cowles C, de Richemond AL, Ehrenwerth J, Nickinovich DG, Pritchard D, Roberson DW, Wolf GL, American Society of Anesthesiologists Task Force on Operating Room Fires. Practice advisory for the prevention and management of operating room fires: an updated report by the American Society of Anesthesiologists Task Force on Operating Room Fires. Anesthesiology. 2013 Feb:118(2):271-90. doi: 10.1097/ALN.0b013e31827773d2. Epub     [PubMed PMID: 23287706]

Level 1 (high-level) evidence

[3]

Jaquet Y, Monnier P, Van Melle G, Ravussin P, Spahn DR, Chollet-Rivier M. Complications of different ventilation strategies in endoscopic laryngeal surgery: a 10-year review. Anesthesiology. 2006 Jan:104(1):52-9     [PubMed PMID: 16394690]

Level 2 (mid-level) evidence

[4]

Tagaito Y,Isono S,Nishino T, Upper airway reflexes during a combination of propofol and fentanyl anesthesia. Anesthesiology. 1998 Jun;     [PubMed PMID: 9637637]

Level 1 (high-level) evidence

[5]

Estis G,Ezri T,Tomori Z, Cough, expiration and aspiration reflexes: possible anesthetic implications - a brief review. Romanian journal of anaesthesia and intensive care. 2014 Oct;     [PubMed PMID: 28913442]


[6]

Widdicombe J. Upper airway reflexes. Current opinion in pulmonary medicine. 1998 Nov:4(6):376-82     [PubMed PMID: 10813220]

Level 3 (low-level) evidence

[7]

Youssef DL, Paddle P. Tubeless Anesthesia in Subglottic Stenosis: Comparative Review of Apneic Low-Flow Oxygenation With THRIVE. The Laryngoscope. 2022 Jun:132(6):1231-1236. doi: 10.1002/lary.29885. Epub 2021 Sep 29     [PubMed PMID: 34585757]

Level 2 (mid-level) evidence

[8]

Roy S, Smith LP. Surgical fires in laser laryngeal surgery: are we safe enough? Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery. 2015 Jan:152(1):67-72. doi: 10.1177/0194599814555853. Epub 2014 Oct 24     [PubMed PMID: 25344591]


[9]

Epstein RH,Halmi BH, Oxygen leakage around the laryngeal mask airway during laser treatment of port-wine stains in children. Anesthesia and analgesia. 1994 Mar;     [PubMed PMID: 8109765]


[10]

Johansen M, Daniel SJ, Engelhardt T. Use of nasal high flow in upper airway surgery with laser. Paediatric anaesthesia. 2022 Jan:32(1):90-91. doi: 10.1111/pan.14317. Epub 2021 Nov 9     [PubMed PMID: 34709691]


[11]

Jiam NT, Dwyer CD, Rosen CA. Awake Laser Laryngeal Stenosis Surgery. The Laryngoscope. 2021 May:131(5):E1633-E1637. doi: 10.1002/lary.29295. Epub 2020 Dec 2     [PubMed PMID: 33264421]


[12]

Reinisch L. Laser physics and tissue interactions. Otolaryngologic clinics of North America. 1996 Dec:29(6):893-914     [PubMed PMID: 8890123]

Level 3 (low-level) evidence

[13]

Ries WR,Clymer MA,Reinisch L, Laser safety features of eye shields. Lasers in surgery and medicine. 1996;     [PubMed PMID: 8778527]


[14]

Colquhoun-Flannery W, Carruth JA, Cheesman AD. Laryngeal papillomatosis with subsequent development of papillomata in the paranasal sinuses--is it seeding by intubation? The Journal of laryngology and otology. 1995 Mar:109(3):238-9     [PubMed PMID: 7745344]

Level 3 (low-level) evidence

[15]

. Control of smoke from laser/electric surgical procedures. National Institute for Occupational Safety and Health. Applied occupational and environmental hygiene. 1999 Feb:14(2):71     [PubMed PMID: 10457631]

Level 1 (high-level) evidence

[16]

McRae K. Anesthesia for airway surgery. Anesthesiology clinics of North America. 2001 Sep:19(3):497-541, vi     [PubMed PMID: 11571904]


[17]

Putz L,Mayné A,Dincq AS, Jet Ventilation during Rigid Bronchoscopy in Adults: A Focused Review. BioMed research international. 2016;     [PubMed PMID: 27847813]


[18]

Ebeling CG, Riccio CA. Apneic Oxygenation With High-Flow Nasal Cannula and Transcutaneous Carbon Dioxide Monitoring During Airway Surgery: A Case Series. A&A practice. 2019 May 15:12(10):366-368. doi: 10.1213/XAA.0000000000000931. Epub     [PubMed PMID: 30475239]

Level 2 (mid-level) evidence

[19]

Benninger MS, Zhang ES, Chen B, Tierney WS, Abdelmalak B, Bryson PC. Utility of Transnasal Humidified Rapid Insufflation Ventilatory Exchange for Microlaryngeal Surgery. The Laryngoscope. 2021 Mar:131(3):587-591. doi: 10.1002/lary.28776. Epub 2020 Jun 16     [PubMed PMID: 32542687]


[20]

Bo L,Wang B,Shu SY, Anesthesia management in pediatric patients with laryngeal papillomatosis undergoing suspension laryngoscopic surgery and a review of the literature. International journal of pediatric otorhinolaryngology. 2011 Nov;     [PubMed PMID: 21907420]

Level 2 (mid-level) evidence

[21]

Li SQ, Chen JL, Fu HB, Xu J, Chen LH. Airway management in pediatric patients undergoing suspension laryngoscopic surgery for severe laryngeal obstruction caused by papillomatosis. Paediatric anaesthesia. 2010 Dec:20(12):1084-91. doi: 10.1111/j.1460-9592.2010.03447.x. Epub     [PubMed PMID: 21199117]


[22]

Roy S, Smith LP. Preventing and Managing Operating Room Fires in Otolaryngology-Head and Neck Surgery. Otolaryngologic clinics of North America. 2019 Feb:52(1):163-171. doi: 10.1016/j.otc.2018.08.011. Epub 2018 Sep 18     [PubMed PMID: 30241765]


[23]

Jones TS, Black IH, Robinson TN, Jones EL. Operating Room Fires. Anesthesiology. 2019 Mar:130(3):492-501. doi: 10.1097/ALN.0000000000002598. Epub     [PubMed PMID: 30664060]


[24]

Lolis M,Dunbar SW,Goldberg DJ,Hansen TJ,MacFarlane DF, Patient safety in procedural dermatology: Part II. Safety related to cosmetic procedures. Journal of the American Academy of Dermatology. 2015 Jul;     [PubMed PMID: 26089046]


[25]

Barkana Y, Belkin M. Laser eye injuries. Survey of ophthalmology. 2000 May-Jun:44(6):459-78     [PubMed PMID: 10906379]

Level 3 (low-level) evidence

[26]

Bigony L. Risks associated with exposure to surgical smoke plume: a review of the literature. AORN journal. 2007 Dec:86(6):1013-20; quiz 1021-4     [PubMed PMID: 18068405]

Level 3 (low-level) evidence