|Year : 2022 | Volume
| Issue : 4 | Page : 487-493
Review and practical recommendations for peripheral nerve block during Coronavirus Disease-2019 pandemic
Sangeeta Khanna, GV Krishna Prasad
Department of Anesthesiology, Dr DY Patil Medical College, Hospital and Research Centre, Dr DY Patil Vidyapeeth, Pune, Maharashtra, India
|Date of Submission||21-Jul-2020|
|Date of Decision||27-Nov-2020|
|Date of Acceptance||25-Feb-2021|
|Date of Web Publication||28-Mar-2022|
G V Krishna Prasad
Military Hospital, Kirkee, Pune, Maharashtra
Source of Support: None, Conflict of Interest: None
Coronavirus disease-2019 (COVID-19) was announced as a global pandemic by the World Health Organization on March 11, 2020 due to its rapid spread and multinational involvement. Operating room preparedness in these times should encompass increased vigilance, protective measures, and alternative procedures in an effort to mitigate the spread from a proven or suspected case. Specifically, by reducing aerosol-generating procedures as in general anesthesia, anesthesiologists can decrease exposure to patient's respiratory secretions and transmission of virus to the health-care professional and other patients. The Interoperability Standards Advisory in its advisory has also recommended regional anesthesia over general anesthesia as one of the steps that can reduce aerosol spread. Further, to restrict airway manipulation, peripheral nerve blocks (PNB) should be considered whenever possible in suspected or confirmed cases of COVID-19 undergoing surgery. PNB has the advantage of maintenance of respiratory functions, prevention of aerosolization, and so preventing viral transmission. This article explores the practical information and suggested measures for conducting PNB in COVID-19 patients with suggestions toward resource planning, clinical environment modification, equipment preparation, supply of drugs, choosing of correct personal protective equipment, safe PNB procedures, anesthesia monitoring, and postanesthetic care. By addressing these issues, infection control during anesthesia can be achieved and which is essential in the present era with emerging infection and novel pathogens such as coronavirus 2 causing the severe acute respiratory syndrome. Thus, framing a structured protocol for PNB among these patients is essential for the best perioperative outcome.
Keywords: Aerosol spread, coronavirus disease-2019, general anesthesia, peripheral nerve block, safety, severe acute respiratory syndrome coronavirus 2
|How to cite this article:|
Khanna S, Krishna Prasad G V. Review and practical recommendations for peripheral nerve block during Coronavirus Disease-2019 pandemic. Med J DY Patil Vidyapeeth 2022;15:487-93
|How to cite this URL:|
Khanna S, Krishna Prasad G V. Review and practical recommendations for peripheral nerve block during Coronavirus Disease-2019 pandemic. Med J DY Patil Vidyapeeth [serial online] 2022 [cited 2022 Jul 5];15:487-93. Available from: https://www.mjdrdypv.org/text.asp?2022/15/4/487/341052
| Introduction|| |
Coronavirus disease 2019 (COVID-19) is primarily a respiratory disease and the chief causative agent is the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The coronavirus belongs to the Coronaviridae family which is one of the causative agents for acute upper respiratory tract infections. The mode of transmission is through the droplet, which is similar to SARS-CoV-2 and cold viruses. The current pandemic was announced on March 11, 2020 and the first case was reported from Wuhan, China. Since January 2020, there has been a global spread with Italy, Spain, and the United States having the maximum number of cases with high mortality figures. General anesthesia (GA) procedures performed by anesthesiologists are known to generate maximum aerosols, thus imposing increased risk to health-care professionals irrespective of the disease severity. Usually, GA involves a wide range of techniques such as bag-mask ventilation, open airway suctioning, and endotracheal intubation. However, to avoid airway manipulation, the use of techniques such as peripheral nerve block (PNB), central neuraxial blocks are recommended.
The benefits of PNB over GA are better postoperative pain management and reduction in the dose of opioids, Moreover, the reduction in postoperative pulmonary complications, nausea and vomiting, cognitive dysfunction, and delirium are some additional advantages of PNB over GA. Further, using PNB in patients with viral respiratory infections, restriction of airway instrumentation and avoidance of coughing in patients which occurs during intubation and extubation reduce the chance of infection among the health-care workers in the surgical room through the aerosol generation and virus particles dispersion., With a lot of credibility of PNB over GA in managing the subjects affected with COVID-19, only limited literature is available till date on the advantages of PNB. So in this backdrop, the present review aims to underscore the evidence-based practical procedures and recommendations for performing PNB in COVID-19 patients, thus ensuring the safety of patients and health-care staff.
| Methodology|| |
The formal literature approach was performed for the following domain in COVID-19. They were as follows: planning of resources and staffing; preparation of clinical rooms; environment; preparation of equipment, supplies, and drugs; choosing of accurate personal protective equipment (PPE); ensuring adequate oxygen therapy; evaluating safety procedures for PNBs techniques; and monitoring of anesthesia methods and recovery of anesthesia. The searches were done in English terms and limited to human studies for the publication date between January 1, 2000 and May 15, 2020. The terms COVID-19 (or SARS or H1N1 or MERS); anesthesia; surgery; and/or operating rooms were used for the search.
| Results|| |
Peripheral nerve block approaches in COVID-19 cases and guidelines
The latest American Society of Regional Anesthesia and Pain Medicine (ASRA) guidelines state that whenever possible, regional anesthesia (RA) is recommended over GA in COVID-19 patients to minimize the requirement of aerosol-generating medical procedures.
Steps to be followed before performing peripheral nerve blocks
Reduction in the volume of surgical procedures to get ample time for planning in COVID-19 patients is essential. Preservation of existing stock of PPE, delaying elective surgeries to reduce the risk of transmission in patients and health-care workers, and conservation of health-care sources are required to meet the demand.
Transport of coronavirus disease 2019 patient within the hospital
Transferring of COVID-19 patients from an isolation area to the operation room involves higher risk for virus spreading in the environment as well as to health-care individuals. To avoid the risk of contamination, the patients should be protected with surgical face mask during shifting from the isolation ward to operation theater and health-care professionals present along with the patients should fit with the National Institute of Occupational Safety and Health-certified N95 respirators, eye safety goggles, or complete shield protecting the face, caps, and full-length gowns and hand gloves. Further, the patients must be transported through specific routes to reduce the contact with other staff, and during this transfer, a nurse specialized in handling infection control should be present to restrict the contamination and also to increase the compliance.
| Preoperative Assessment|| |
In developing countries, informed consent is still in the paper format. There is a chance of marked contamination during the acceptance of informed consent. In this regard, the informed consent can be obtained by digital methods using single plastic-wrapped tablets or mobile phones from patients or attenders. Thorough preoperative counseling is important to rule out any other associated illnesses. For example, patients with current morbidity such as chronic obstructive pulmonary disease and superadded with COVID-19 may pose difficulty in the peri-operative period for using anesthetic methods such as interscalene blocks. An alternative method like supra or infraclavicular block should be planned in the preoperative period for the safe conduct of anesthesia.
| Operating Room Preparation|| |
The ORs with negative pressure are suitable to reduce the infection. In general, ORs are constructed in such a way it has positive pressure air circulation. An elevated air exchange cycle rate (≥25 cycles/h) is highly efficient to minimize the viral spread inside the ORs. Further, only minimal essential equipment must be maintained in ORs depending on the cases. After the start of surgery, the health-care staff are encouraged to depend on the resources available in the room and also instructed to minimize the entry and exit of OR to reduce the infection risk. The standard anesthetic trolleys must be avoided, instead of preprepared trolley with lesser and quantum stocks can be used. The surgical equipment should be sterilized with essential covering before the entry into the OR. Specific well-identifiable containers for infectious-risk health waste containers should be placed for the disposal of infected equipment. Alcoholic solution to sterilize the hands must be present constantly in the OR. The OR door must be kept closed and unwanted entry in the donning and doffing area is restricted. Surgeons must perform the procedures using the equipment present in OR, and during the operation, any additional vital equipment must be supplied by the staff outside the OR. The elective devices such as ultrasound and other devices surface must be protected with cover with proper sanitation postsurgery [Figure 1].
|Figure 1: The nonessential parts of the ultrasound machine are covered using drapes, gown, or plastic and sheaths are used to cover the probe and cord covering|
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The surgeons must cover the patient as per the requirement of the surgical procedure by replacing the surgical mask with FFP2 filter and long shoe cover. The health-care personnel who are in contact with COVID-19 patients during the procedure must wear a PPE. Once the patient is transferred from the OR after the procedure, there should enough time for the preparation of the next procedure to reduce the air contamination and this period is depending on the number of air exchanges/hour. The air exchange cycles must be elevated to ≥25 exchanges/h whenever needed (Centers for Disease Control and Prevention, 2019).
| Peripheral Nerve Blocks during Intraoperative Period in Coronavirus Disease 2019 Sedation|| |
Heightened care and monitoring should be undertaken while sedating COVID-19 patients since they are already prone to respiratory depression as a result of COVID-19 associated pneumonia. Further, there should be strict monitoring of oxygenation and ventilation when the patients are sedated. Albeit, facility for carbon dioxide (CO2) monitoring must be available instantly in the OR in the case of sedated patients. Further, the CO2 sampling line must not be connected directly to the patient monitor since there is a high chance of contamination. In a review done by Lie et al., it was brought out that to prevent contamination, a connection between a 15-mm endotracheal tube connector and a high-efficiency particulate air (HEPA) heat and moisture exchanging (HME) filter can be directly incorporated to a simple face mask or introduced by a cut segment of suction tubing. Further, sampling line of CO2 is attached to HEPAHME for filtering of sample gas. The other way, the respiratory rate can be measured and evaluated by expert anesthesiologists through electrocardiogram systems.
| Oxygen Therapy|| |
While treating the COVID-19 patients by health-care personnel, another vital factor to be taken into consideration is the exhaled air dispersion distance in the event of oxygen therapy and ventilatory support. Administration of oxygen through nasal cannula, venturi mask, oronasal masks, and noninvasive ventilation (NIV) should be restricted to decrease the risk of infection through aerosolization and cross infection.,,
Coughing, in the absence of mask, elicits an exhaled air jet on a median sagittal plane of 68 cm from a human patient simulator and when the surgical mask is used, there is a decrease in distance up to 30 cm and when N95 mask is used, the distance is further reduced to 15 cm. However, it should be noted that mask wearing does not restrict the air leakage between the mask and the skin and the air dispersion distance in a surgical mask and N95 mask is 28 cm and 15 cm, respectively.
Thus, continuous positive airway pressure through oronasal mask and NIV through a helmet fixed with inflatable neck cushion are the suitable ventilatory techniques that reduce the room air contamination [Figure 2].,
|Figure 2: Ventilatory methods used for the oxygen therapy. (a) Oronasal mask; (b) noninvasive ventilation helmet|
Click here to view
The flow of supplemental oxygen should be kept to the minimum (preferably <5 L/min) needed to maintain arterial oxygen saturation to reduce the risk of aerosolization.
| Personal Protective Equipment Considerations and Challenges Faced by Anesthesiologist|| |
Specific PPE components used for the aerosol-generating methods may vary between the hospitals. The various PPE components used for the protection are, particulate respirator (US National Institute for Occupational Safety and Health-certified N95, powered air-purifying respirator (PAPR), EU standard FFP2, eye protection through goggles or a disposable face shield, fluid resistance gowns and gloves. Previous studies show that PAPR utilization in a laminar flow OR displayed no elevation in particulate transfer to the surgical field. In addition, PAPRs eliminated colony-forming units in an OR environment versus a 95% reduction when wearing a standard surgical mask. Alternatively, a regular surgical mask may be worn under a PAPR [Figure 3] or over a facemask respirator with an expiratory valve to afford standard protection from clinicians' exhaled air in the OR. In addition, several publications recommend PAPRs for use in extremely aerosolizing procedures of the airway, lung, sinus oropharynx, and skull base surgery. Further, PNB teams must be limited to one expert anesthetist accompanied with an skilled assistant (intensive care unit nurse or surgical practitioner), and one chief expert as a reserve anesthetist for drug administration. PPE components such as goggles and face shields may hamper the vision during the block procedure, which can be overcome by repeated practices. Hence, training of the trainers is important before the procedure.
| Assessment of Peripheral Nerve Blocks|| |
The block height is evaluated by applying the reusable ice bags on the target area. There is a high change of contamination when it is applied onto the patient's skin surface. In case reusable ice bags are used, it should be placed in disposable plastic bags and it should be surface sterilized using a suitable disinfectant like quaternary ammonium chloride solutions. Or else, ice cubes can be packed in sterilized plastic bags for single use. Other methods like the pinprick approach using a sterilized needle might be an effective alternative.
| Ultrasound Machine|| |
Equipment safety is important during the contagious diseases like COVID-19. USG machine should be dedicated to a particular OR. It should not be moved around the other places in the OR complex. Sanitation and cleaning of the USG machine is very important after the procedure so as to contain the disease spread [Figure 1]. Furthermore, the USG machine can be used intraoperatively for monitoring the patient's condition like, assessment of lung, for central venous cannulation, etc.
| Postoperative|| |
Recovery from anesthesia
It is compulsory for COVID-19 patients to be sent to an isolation room in the postoperative ward after surgery, without shifting to the postanesthesia care unit. Once the patient meets the criteria for recovery, the vitals should be monitored and sent to a specified area.
Postanesthesia medical waste disposal
Medical waste should be sorted and disposed of without delay. All the medical waste should be double bagged and marked as “COVID-19,” and the labeling should include department name, institute name, time and date, and the category. Before disposing the bags, it must be sealed and disinfected with chlorinated spray solutions or it may be covered with an additional bag and sealed. Medical waste produced in the clean area can be treated in a routine fashion.
| Complication of Peripheral Nerve Block and the Risk of Contamination|| |
Failed peripheral nerve block and risk of spread
Before starting the surgery, the block must be properly evaluated to meet the optimal surgical conditions and also to avoid immediate change over to GA in the event of surgery. So if conversion to GA is required, the anesthesiologists might in a hurry don the PAPR, which may increase the chance of contamination and cross over the infection control barrier. To avoid this, the anesthesiologist should don the PAPR suitable for both PNB and GA, in such a way that they can shift to GA during operational emergencies in a short period with safety. Further, when there is a conversion to GA, the anesthesiologist must strictly adhere to PPE guidelines and apply an induction method where there is minimal aerosol generation.,
Complications of peripheral nerve blocks
In the case of brachial plexus blocks, the specific noxious complications such as diaphragmatic paralysis which encompasses pneumothorax and phrenic nerve involvement leading to respiratory depression in COVID-19 patients. Only experienced anesthesiologists should perform this technique and the needle tip should be highly monitored to avoid pneumothorax. Diaphragmatic paralysis occurs as a result of blocking effects of local anesthetics (LA) on the phrenic nerve at the level between C3 and C5. To prevent or reduce the incidence of diaphragmatic paralysis, altering the dose of LA by reducing the volume or concentration, site of injection, or alternate technique like the suprascapular or infraclavicular block is recommended and explored. Upper limb blocks should be performed with extra vigilant so as to prevent the contamination, being close proximity to the face of the patient.
| Local Anesthetics Systemic Toxicity|| |
An effective safe dose of LA should be administered to prevent the local anesthetics systemic toxicity (LAST) in COVID-19 patients. Further, US-guided PNB is highly effective in the mitigation of LAST. If the COVID-19 patients are detected with LAST, an emergency status must be created and need of additional personnel must be instructed who should be protected with PPE/PAPR before entering the OR to ward off the condition. Further, the anesthesia drug trolley trays encompassing the resuscitation drugs and defibrillator cart should be ready. Intralipid should be available in the OR, always to tackle the LAST.
| Specific Investigations|| |
A positive real-time polymerase chain reaction result confirms SARS-CoV-2 infection and the pooled sensitivity has been estimated to be 87.8%, with the specificity estimated to be in the range of 87.7%–100%.
Pulse oximetry is a simple tool to detect silent hypoxia in COVID-19 cases since their oxygen saturations can drop to low levels and precipitate acute respiratory failure without the presence of obvious symptoms of respiratory distress.
| Examination Methods|| |
In the early stage of the disease, a normal or decreased total white blood cell count (WBC) and a decreased lymphocyte count can be demonstrated. Interestingly, lymphopenia appears to be a negative prognostic factor. Increased values of liver enzymes, lactate dehydrogenase, muscle enzymes, and C-reactive protein can be detected. The elevated neutrophil-to-lymphocyte ratio (NLR), derived NLR ratio (neutrophil count divided by the result of WBC count minus neutrophil count), and platelet-to-lymphocyte ratio, can be the expression of the inflammatory storm.
| Imaging Modalities|| |
Thoracic high-resolution computed tomography (HRCT), a highly feasible imaging method, plays an important role in the screening and treatment evaluation of COVID-19. A study conducted on 63 COVID-19 patients shows that HRCT is a highly feasible imaging method, plays an important role in the screening and treatment evaluation of COVID-19.
| Discussion|| |
The main aim of the present narrative review is to highlight a simple and useful guide for the anesthesiologist performing PNB in suspicious or confirmed cases of COVID-19 patients attending the surgery. Careful monitoring of patients must be followed in OR until safe, before transferring the patient to COVID-19 allocated area in the hospital as instructed in the guidelines. The transmission risk is increased during the removal of PPE, so additional time must be allocated during donning and doffing under the watchful eyes of an observer. Further, if any reusable material is employed, it should be properly disinfected as per institutional guidelines. Ultrasound-guided PNB is a safe alternative in COVID-19 patients as compared to GA. It also facilitates more rapid black onset and extended the block duration with additional merits of reduced dose which further reduces LAST. Less drug volumes can be used in this method and the complications are very minimal.
| Conclusion|| |
PNB restores respiratory function with no evidence of aerosol generation and viral transmission. Hence, PNB must be the first choice of anesthetic technique in suspected or confirmed COVID-19 patients undergoing surgery whenever feasible. Although these recommendations lack the support of well-designed and executed controlled trials, they could still be a useful clinical care guideline for the anesthesiologist who would like to perform RA in a suspected or confirmed COVID-19 infected patient. Furthermore, clinical care protocols are institution specific, so these recommendations may not apply to all health-care facilities. The SARS-CoV-2 virus will be not the last novel virus to trigger pandemics, so having a well-structured RA plan to manage this kind of patients will ensure the best outcome possible to both patients and the anesthesiology team.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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