|Year : 2020 | Volume
| Issue : 2 | Page : 69-74
COVID-19: Considerations for obstetric anesthesia and analgesia
Venkata Ganesh, Ridhima Bhatia, Anjan Trikha
Department of Anaesthesiology, Pain Medicine and Critical Care, AIIMS, New Delhi, India
|Date of Submission||23-Jun-2020|
|Date of Acceptance||24-Jun-2020|
|Date of Web Publication||20-Aug-2020|
Prof. Anjan Trikha
Department of Anaesthesiology, All India Institute of Medical Sciences, New Delhi - 110 029
Source of Support: None, Conflict of Interest: None
Peripartum services are indispensable notwithstanding the COVID-19 pandemic. Providing safe and quality obstetric anesthesia is quite demanding as most signs and symptoms of COVID-19 are non-specific and overlap with the constitutional signs of pregnancy. Overloaded viral testing facilities, urgency of caesarean delivery, limited resources, capricious evidence-base, and potential exposure risk to healthcare providers further add to the challenge imposed by COVID-19. In this discourse we attempt to provide a summary of the current evidence and recommendations concerning the practice of obstetric anesthesia and analgesia.
Keywords: Analgesia, COVID-19, obstetric anesthesia, SARS-Co-V2
|How to cite this article:|
Ganesh V, Bhatia R, Trikha A. COVID-19: Considerations for obstetric anesthesia and analgesia. J Obstet Anaesth Crit Care 2020;10:69-74
|How to cite this URL:|
Ganesh V, Bhatia R, Trikha A. COVID-19: Considerations for obstetric anesthesia and analgesia. J Obstet Anaesth Crit Care [serial online] 2020 [cited 2021 Jun 19];10:69-74. Available from: https://www.joacc.com/text.asp?2020/10/2/69/292747
| Introduction|| |
Since late 2019, an unknown cause of severe acute respiratory infection (SARI), subsequently identified to be caused by a novel beta coronavirus, now designated SARS-CoV2, has caused unprecedented disruption in the provision of medical and surgical services globally. At the time of this writing, this pandemic “coronavirus disease 2019” (abbreviated COVID-19) has involved over 200 countries, over 6 million cases and has caused the death of over 3.5 lakh people world over. Transmission of the virus occurs via aerosol and droplets. The smaller of the two, that is, aerosols, tend to remain suspended in the air for prolonged periods exposing greater number of individuals, even at a greater distance from the source. Droplets have a tendency to settle on surfaces and the virus has been found to survive on fomites promoting contact transmission. Asymptomatic individuals, including children, can also spread the virus.,,, Peripartum services, in contrast to many other healthcare services, cannot be deferred or postponed with the view of redirecting resources towards the overload imposed by COVID-19. Several recommendations and practice guidelines were rapidly made based on the similarities of SARS-CoV2 infection with those of the outbreaks caused by MERS-CoV, SARS and influenza viruses. The new evidence on COVID-19, of which several may be of questionable quality yet nonetheless useful, appears every day and so recommendations may change with time. In this article we try to summarize the available evidence, expert opinions, and recommendations related to the provision of obstetric anesthesia services.
| The “high Infection Risk” Parturient|| |
Prompt identification of patients at high risk of infection is important to limit the spread of infection to other parturients and healthcare workers. The clinical features so far identified in association with COVID 19 include fever, fatigue, cough, myalgia, shortness of breath, sore throat, diarrhea, nausea, headache, and vomiting. Sudden anosmia or hyposmia has also been reported.
It seems apparent from the above description that many of these can be attributed to the constitutional symptoms of pregnancy. This limits the usefulness of using temperature monitoring as the sole clinical tool for screening. Screening for travel and contact history also has limited reliability as nearly every country is infected, asymptomatic spread occurs and because of the local community transmission. Hence all parturients with a history or symptoms suggestive of upper respiratory tract infection (URI) and travel history should be considered as high infection risk or PUI (Patient Under Investigation) and isolated till tested negative. This isolation should ideally be done in an Airborne Infection Isolation Room (AIIR), a negative pressure room with at least 6 air exchanges per hour.
| Clinical Outcome of Covid-19 in Pregnancy|| |
The clinical outcomes of parturients were poor during the SARS and MERS outbreaks with high rates of intubation, organ failure, and consumption coagulopathy.,, The physiological changes in pregnancy predispose these patients to pneumonia and fetal outcomes of women with pneumonia, in terms of growth restriction and in-utero fetal demise, were also worse during the influenza outbreak.,
However, in contrast to the SARS, MERS, and influenza outbreaks the clinical course of COVID-19 appears to be mild in most pregnant patients. This could be because of sex-related immunological differences between men and women which might also explain the higher mortality in infected men. In a joint report of 147 cases in pregnancy, WHO-China have recorded 8% as suffering from severe respiratory disease with SpO2 of <93% and a PaO2/FiO2<300 mmHg. Only 1% of these patients required mechanical ventilation. Liu et al., in a small case series of 13 patients, however, noted higher rates of preterm labor and emergency caesarean sections in view of fetal distress. One of these mothers needed mechanical ventilation and ECMO. Few reports suggest increased chances of preterm births and fetal distress., Preterm births seem to be the most common complication associated with COVID-19. A national cohort study in the United Kingdom reports 27% patients as having had preterm births, of whom 47% required iatrogenic delivery for maternal indications and 15% had fetal distress., But this remains merely an association and no causal link to COVID 19 has been established so far. Vertical transmission has also been reported.,,
| Reorganizing Obstetric Anesthesia Services|| |
A team approach takes precedence in managing the obstetric patient for emergency caesarean section. This team should include contributions from anesthesiology, obstetrics, labor and delivery nurses, neonatology, critical care, infectious disease and infection control, employee health services and telemedicine. They should create established protocols with suitable cognitive aids to streamline the management of COVID-19 patients.
There should be well established lines of communication between the obstetrician and the anesthesia team. A COVID-19 dedicated quick response team (of obstetricians, anesthesiologists and paramedical staff) would enable provision of rapid services. Early information about the possibility of a COVID-19 positive or suspect emergency caesarean section will enable operating room (OR) preparedness and minimize donning time and errors. If the case is a suspect while tests are awaited it is to be managed as a positive case. The increased minute ventilation of pregnancy may increase the chance of droplet spread and hence all suspect cases should be given a surgical mask. Dedicated OR and isolation rooms with separate doffing and donning areas should be identified and modified according to regulatory guidelines to prevent spread of airborne infection to non-COVID areas.
Digital record keeping with remote access and telephonic or videoconferencing should be encouraged in patient evaluation, monitoring, hand-overs, and follow-up to minimize healthcare worker exposure as well as conserve PPE (Personal Protective Equipment).
| Anesthetic Choice and Ppe|| |
- The choice of anesthesia should be dictated by the urgency of the caesarean section rather than the serostatus of the patient. The level of PPE required during a caesarean birth should be determined based on the risk of requiring general anesthesia.
- Regional anesthesia (RA) should be considered as first line,,,,, since it is not an aerosol generating procedure (AGP) as against general anesthesia (GA) which requires airway manipulation.
- The patient should be wearing a surgical mask at all possible times.
- When regional anesthesia is being instituted all non-essential personnel should be outside the procedure room. Only necessary equipment and medication should be inside. A runner with additional equipment may stay outside the procedure room. Those inside should wear a fluid resistant disposable gown (FRDG), gloves, a fluid resistant surgical mask (FRSM) and eye protection. These protect against droplet but not airborne infection.
- In cases where GA is highly likely as in emergency caesarean sections, difficult regional anesthesia (e.g., obesity, scoliosis, poorly functioning labor epidural), full airborne precautions would be ideal.,,, This replaces the FRSM with a N95 or FFP3/FFP2 mask in addition to droplet precautions as above.
- Deciding on anesthetic technique for non-obstetric conditions mandating surgery during pregnancy should follow the same principles.
| Neuraxial Techniques and Covid-19|| |
Although intrathecal seeding of the virus, and meningitis, is theoretically possible, this has not been causatively demonstrated in SARS-CoV2 or even in influenza infection. Similar questions were raised in the past on providing neuraxial anesthesia in viremic patients with HIV, Varicella Zoster Virus (VZV), Herpes simplex viruses (HSV), Ebola, and SARS. A literature search revealed no randomized clinical trials demonstrating meningitis from neuraxial anesthesia in these patients. Reports and observational studies relating to HIV deem neuraxial anesthesia as safe in immunosuppressed obstetric patients.,, Evidence supporting the uneventful use of neuraxial anesthesia for caesarean deliveries in parturients with viremic VZV, MERS, and SARS are limited to case reports and weak practice recommendations.,,, Similar testimonies also support neuraxial techniques in HSV-2 infection., Concerning Ebola, the problem was more in relation to the hemorrhagic nature, of the disease precluding the use of neuraxial techniques. However, no publication has listed these infections, with the exception of injection site VZV, as absolute contraindications for neuraxial procedures. COVID-19 can present with lymphopenia and leukopenia as well. As long as strict aseptic precautions are adhered to, the infection risk to the patient should remain the same as in patients with other causes of immunosuppression (e.g., chemotherapy).
There are few case reports of SARS-CoV2-related spontaneous meningoencephalitis and even fewer such cases where the virus has been isolated from the CSF.,,, But no reports exist to support viral seeding during a lumbar puncture. Case series, totalling 77 patients in the present literature, have reported uneventful neuraxial procedures inclusive of spinal, epidural and combined spinal-epidural (CSE) anesthetics, with an unremarkable postoperative course.,,,, One of these patients was on maximal non-invasive ventilation at the time of caesarean delivery. From the available evidence we may infer that neuraxial techniques are reasonably safe and should be preferred in this group of patients.
A word of caution however is the association between neuraxial techniques and exaggerated hypotension in COVID-19 patients. This will logically be more common in febrile patients. Prophylactic vasopressor infusion can potentially minimize this; however, one should be aware of a possible higher dose requirement in SARS-CoV2 infected patients.
| Coagulation and Covid-19|| |
Thrombocytopenia is another known complication of COVID-19. This is most often mild (100 × 109/L to 150 × 109/L), and counts less than 100 × 109/L were rare (<5%) according to a cohort of 1099 non-pregnant patients., Available evidence, however, suggests the presence of a hypercoagulable state manifesting as low grade disseminated intravascular coagulation (DIC) and thrombotic microangiopathy in non-pregnant patients. This combined with the hypercoagulable state of pregnancy and potential decreased mobility of the mother near term may predispose them to venous thromboembolism (VTE). Hence, these patients may be on prophylactic, in some cases therapeutic, anticoagulation, and timely perioperative titration will be required. A high index of suspicion for VTE should be maintained as patients with COVID-19 may require higher dose of prophylactic anticoagulants which is being evaluated by several trials (IMPROVE, COVID-HEP, X-COVID-19).,,,, Perioperative point of care ultrasound (POCUS) would be a good choice to rule out VTE when feasible. Other point of care tests such as thromboelastography may be of great benefit. In short, all of these patients should have, at minimum, a recent platelet count before proceeding for surgery or neuraxial procedures.
| Labor Analgesia|| |
Early epidural analgesia is recommended by several organizations because of the simple fact that this can also be extended for intraoperative use. However, after placement one should regularly follow-up the quality of analgesia to assess the functioning of the epidural. Remote assessment using numerical rating scales for pain should be adequate. Droplet precautions are considered adequate for epidural placement. Dosing of epidural opioids should be done with caution and long acting opioids avoided, especially in patients with respiratory symptoms and low oxygen saturation (<95%) as it may cause respiratory depression.
Entonox may be used as it is not considered an AGP, however droplet precautions must be in place and the equipment circuit should have a viral filter. IV PCA using fentanyl and remifentanil should ideally be avoided as they may cause respiratory depression, nausea, and vomiting. Ketorolac, ibuprofen and NSAIDs have been poorly associated with aggravating the infection trajectory of COVID-19 and should be avoided in sick patients., Paracetamol might be safer alternative.
| Preoperative Evaluation|| |
All patients should be thoroughly evaluated (with minimal contact) including vital signs, modified physical examination (such as POCUS lung ultrasound instead of auscultation), laboratory tests (blood counts, metabolic panel, blood gases if needed) as this will enable planning appropriate care and monitoring. Continuous pulse oximetry and strict titration of fluid balance are a must. Early detection and treatment of hypoxia is important as undetected it can cause fetal hypoxia and distress becoming an indication for an emergent caesarean section. Oxygen can be supplemented via face mask or nasal prongs with a FRSM over the device which can limit the droplet spread. Increasing oxygen requirements will serve as a marker for disease progression and decision to institute assisted ventilation, be it invasive or non-invasive, should be taken early so that it may be done in a controlled manner with adequate precautions. Adequate precautions should be taken while transferring patients to and from dedicated OR/perioperative room.
| Intraoperative Management|| |
Standard monitoring should be in place with a dedicated OR (ideally an AIIR), protected anesthesia workstation and only essential equipment and personnel inside the OR. In a category 4 caesarean, the surgical team may wait outside while neuraxial block is confirmed and then scrub into PPE for droplet precautions. However, in urgent, emergent scenarios where GA is likely, minimum personnel donned in full airborne PPE should be at the ready before anesthesia is instituted. Paperless intraoperative recordkeeping will be best. Avoid excessive intraoperative fluids.
Spinal anesthesia, CSE or extension of labor epidural can be used depending on the operator preference. Prophylactic vasopressor should be used instead of overzealous preloading/co-loading. A single shot technique with a thin spinal needle (26-25G) might be preferable as this is less traumatic and may decrease the amount of viremic blood seeding the neuraxis. Single shot hyperbaric bupivacaine, 15 to 25 μg fentanyl with morphine (not more than 100 μg) can be used. However, prophylactic antiemetic administration is a must. Some recommend against the use of dexamethasone, but nevertheless at least ondansetron should be used, but potential QT-prolongation should be considered. The addition of morphine is suggested to cover the postoperative pain, but the decision should be individualized to the patient, that is, avoid in respiratory compromise as well as high-risk PONV cases. In these cases, analgesia may be provided using local infiltration, transversus abdominis plane block, epidural analgesia, or paracetamol.
If GA is required, only essential personnel with barrier intubation devices should be present in the OR. Follow local standard operating procedures for induction. Preoxygenation, with low flows in a closed circuit, can be performed after achieving a good 2-handed mask seal. Avoid positive pressure ventilation or when unavoidable, assist with low volume breaths. Perform rapid sequence induction and intubation (RSII) using video-laryngoscopy as the first line. Single use supraglottic devices to be used as back-up only for a “cannot ventilate” situation. The rest of the team may enter in airborne PPE after successful intubation. Pregnant patients tend to have a physiologic decrease in PaCO2 and hence, if possible, ventilation should be titrated to maintain this in the range of 28–31 mmHg to augment off-loading of oxygen to the fetus. Else, a lung protective strategy should be followed such as the ARDS net ventilator protocol and the first priority should always be maintaining oxygenation. All GA patients should be allowed to recover in the same OR if they can be extubated. Else transfer to a dedicated ICU. Carboprost should be avoided for prophylaxis against postpartum hemorrhage as this can cause bronchospasm., Oxytocin and methylergonovine may be used appropriately.
| Postoperative Management|| |
Standard postoperative care should be instituted with emphasis on continuous pulse oximetry, appropriate isolation of mother and child, judicious fluid, and pain management. Controlling postoperative pain is important as this may worsen hypoxia as tachypnoea increases the work of breathing. Postdural puncture headache (PDPH) should be managed conservatively with supine bed rest, judicious fluids, paracetamol, and caffeine. Epidural saline maybe considered in place of an autologous blood patch in intractable cases. A case-by-case approach is recommended. In sick patients it is advisable to postpone the blood patch.
| Psychological Welfare|| |
It can be appreciated than a label of “COVID-19 positive” can significantly increase the stress of both patients and the attending healthcare team alike and this would not be favorable for maternal or fetal well-being., Hospital support groups and mental health professionals may help in this regard through telemedicine.
| Conclusions|| |
Most pregnant women with COVID-19 are either asymptomatic or present with mild disease., It is, therefore, important to maintain a high index of suspicion and treat all suspect as COVID-19 positive unless proven otherwise. This involves establishing a system of rapid communication, dedicated management areas and workflow, avoiding AGPs, minimizing personnel exposure and appropriate yet adequate PPE. Early epidural analgesia and intraoperative neuraxial anesthesia are preferred.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Rothe C, Schunk M, Sothmann P, Bretzel G, Froeschl G, Wallrauch C, et al
. Transmission of 2019-nCoV infection from an asymptomatic contact in Germany [Internet]. New England Journal of Medicine. Massachusetts Medical Society; 2020 [cited 2020 May 10]. Available from: https://www.nejm.org/doi/10.1056/NEJMc2001468
Xia H, Zhao S, Wu Z, Luo H, Zhou C, Chen X. Emergency Caesarean delivery in a patient with confirmed COVID-19 under spinal anaesthesia. Br J Anaesth 2020;124:e216-8.
Qiu H, Wu J, Hong L, Luo Y, Song Q, Chen D. Clinical and epidemiological features of 36 children with coronavirus disease 2019 (COVID-19) in Zhejiang, China: An observational cohort study. Lancet Infect Dis 2020;20:689-96.
Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, et al
. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus–infected pneumonia in Wuhan, China. JAMA 2020;323:1061-9.
Wong SF, Chow KM, Leung TN, Ng WF, Ng TK, Shek CC, et al
. Pregnancy and perinatal outcomes of women with severe acute respiratory syndrome. Am J Obstet Gynecol 2004;191:292-7.
Assiri A, Abedi GR, Al Masri M, Bin Saeed A, Gerber SI, Watson JT. Middle east respiratory syndrome coronavirus infection during pregnancy: A report of 5 cases from Saudi Arabia. Clin Infect Dis 2016;63:951-3.
Alserehi H, Wali G, Alshukairi A, Alraddadi B. Impact of middle east respiratory syndrome coronavirus (MERS-CoV) on pregnancy and perinatal outcome. BMC Infect Dis 2016;16:105.
Fowler RA, Guest CB, Lapinsky SE, Sibbald WJ, Louie M, Tang P, et al
. Transmission of severe acute respiratory syndrome during intubation and mechanical ventilation. Am J Respir Crit Care Med 2004;169:1198-202.
Hartert TV, Neuzil KM, Shintani AK, Mitchel EF, Snowden MS, Wood LB, et al
. Maternal morbidity and perinatal outcomes among pregnant women with respiratory hospitalizations during influenza season. Am J Obstet Gynecol 2003;189:1705-12.
Bampoe S, Odor PM, Lucas DN. Novel coronavirus SARS-CoV-2 and COVID-19. Practice recommendations for obstetric anaesthesia: What we have learned thus far. Int J Obstet Anesth 2020;43:1-8.
Jaillon S, Berthenet K, Garlanda C. Sexual dimorphism in innate immunity. Clinic Rev Allerg Immunol 2019;56:308-21.
Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, et al
. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: A descriptive study. Lancet 2020;395:507-13.
Liu Y, Chen H, Tang K, Guo Y. Clinical manifestations and outcome of SARS-CoV-2 infection during pregnancy. J Infect 2020. doi: 10.1016/j.jinf.2020.02.028.
Di Mascio D, Khalil A, Saccone G, Rizzo G, Buca D, Liberati M, et al
. Outcome of coronavirus spectrum infections (SARS, MERS, COVID-19) during pregnancy: A systematic review and meta-analysis. American J Obstet Gynecol MFM 2020;2:100107.
Banaei M, Ghasemi V, Naz MSG, Kiani Z, Rashidi-Fakari F, Banaei SB, et al
. Obstetrics and neonatal outcomes in pregnant women with COVID-19: A systematic review. Iranian J Public Health 2020;49:38-47.
Knight M, Bunch K, Vousden N, Morris E, Simpson N, Gale C, et al
. Characteristics and outcomes of pregnant women hospitalised with confirmed SARS-CoV-2 infection in the UK: A national cohort study using the UK Obstetric Surveillance System (UKOSS). medRxiv 2020;2020.05.08.20089268.
Chen H, Guo J, Wang C, Luo F, Yu X, Zhang W, et al
. Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: A retrospective review of medical records. Lancet 2020;395:809-15.
Dong L, Tian J, He S, Zhu C, Wang J, Liu C, et al
. Possible vertical transmission of SARS-CoV-2 from an infected mother to her newborn. JAMA 2020;323:1846-8.
Malhotra N, Bajwa SJS, Joshi M, Mehdiratta L, Trikha A. COVID operation theatre- advisory and position statement of Indian Society of Anaesthesiologists (ISA National). Indian J Anaesth 2020;64:355.
Macfarlane AJR, Harrop-Griffiths W, Pawa A. Regional anaesthesia and COVID-19:First choice at last? Br J Anaesth 2020. doi: 10.1016/j.bja.2020.05.016.
ICMR, Guidance for Management of Pregnant Women in COVID-19 Pandemic. 17p.
Lee AI, Hoffman MJ, Allen NN, Sullivan JT. Neuraxial labor analgesia in an obese parturient with influenza A H1N1. Int J Obstet Anesth 2010;19:223-6.
Gimeno AM, Errando CL. Neuraxial regional anaesthesia in patients with active infection and sepsis: A clinical narrative review. Turk J Anaesthesiol Reanim 2018;46:8-14.
Hughes SC, Dailey PA, Landers D, Dattel BJ, Crombleholme WR, Johnson JL. Parturients infected with human immunodeficiency virus and regional anesthesia. Clinical and immunologic response. Anesthesiology 1995;82:32-7.
Evron S, Glezerman M, Harow E, Sadan O, Ezri T. Human immunodeficiency virus: Anesthetic and obstetric considerations. Anesth Analg 2004;98:503-11.
Ray BR, Singhal D, Kumar A, Borle A, Baidya DK. Anesthesia for cesarean section in a parturient with acute varicella: Is general anesthesia better than neuraxial anesthesia? J Obstet Anaesth Crit Care 2012;2:105. [Full text]
Ngan Kee WD, Leung TN. Severe acute respiratory syndrome (SARS). Int J Obstet Anesth 2003;12:151-2.
Park MH, Kim HR, Choi DH, Sung JH, Kim JH. Emergency cesarean section in an epidemic of the middle east respiratory syndrome: A case report. Korean J Anesthesiol 2016;69:287-91.
Maxwell C, McGeer A, Tai KFY, Sermer M. Management guidelines for obstetric patients and neonates born to mothers with suspected or probable severe acute respiratory syndrome (SARS). J Obstet Gynaecol Can 2009;31:358-64.
Bader AM, Camann WR, Datta S. Anesthesia for cesarean delivery in patients with herpes simplex virus type-2 infections. Reg Anesth 1990;15:261-3.
Crosby ET, Halpern SH, Rolbin SH. Epidural anaesthesia for caesarean section in patients with active recurrent genital herpes simplex infections: A retrospective review. Can J Anaesth 1989;36:701-4.
Ranasinghe JS, Missair A, Moaveni DM, Zahid ZD, Hochman-Cohn J. Ebola virus disease in pregnancy and anesthetic consideration. J Hosp Adm 2015;4:13-7.
Missair A, Marino MJ, Vu CN, Gutierrez J, Missair A, Osman B, et al
. Anesthetic implications of ebola patient management: A review of the literature and policies. Anesth Analg 2015;121:810-21.
Huang YH, Jiang D, Huang JT. SARS-CoV-2 detected in cerebrospinal fluid by PCR in a case of COVID-19 encephalitis. Brain Behav Immun 2020;87:149.
Saiegh FA, Ghosh R, Leibold A, Avery MB, Schmidt RF, Theofanis T, et al
. Status of SARS-CoV-2 in cerebrospinal fluid of patients with COVID-19 and stroke. J Neurol Neurosurg Psychiatry 2020. doi: 10.1136/jnnp-2020-323522.
Helms J, Kremer S, Merdji H, Clere-Jehl R, Schenck M, Kummerlen C, et al
. Neurologic features in severe SARS-CoV-2 infection. N
Eng J Med 2020;382:2268-70.
Moriguchi T, Harii N, Goto J, Harada D, Sugawara H, Takamino J, et al
. A first case of meningitis/encephalitis associated with SARS-coronavirus-2. Int J Infect Dis 2020;94:55-8.
Breslin N, Baptiste C, Miller R, Fuchs K, Goffman D, Gyamfi-Bannerman C, et al
. Coronavirus disease 2019 in pregnancy: Early lessons. Am J Obstet Gynecol MFM 2020;2:100111.
Bauer ME, Chiware R, Pancaro C. Neuraxial procedures in COVID-19 positive parturients: A review of current reports. Anesth Analg 2020. doi: 10.1213/ANE.0000000000004831.
Song L, Song L, Song L. Anesthetic management for emergent Cesarean delivery in a parturient with recent diagnosis of coronavirus disease 2019 (COVID-19): A case report. Transl Perioper Pain Med 2020;7:234-37.
Chen R, Zhang Y, Huang L, Cheng B, Xia Z, Meng Q. Safety and efficacy of different anesthetic regimens for parturients with COVID-19 undergoing Cesarean delivery: A case series of 17 patients. Can J Anesth 2020;67:655-63.
Guan W, Ni Z, Hu Y, Liang W, Ou C, He J, et al
. Clinical characteristics of coronavirus disease 2019 in China. N
Eng J Med 2020;382:1708-20.
Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al
. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet 2020;395:497-506.
Levi M, Thachil J, Iba T, Levy JH. Coagulation abnormalities and thrombosis in patients with COVID-19. Lancet Haematol 2020;7:e438-40.
Niguarda Hospital. Enoxaparin for Thromboprophylaxis in Hospitalized COVID-19 Patients: Comparison of 40 mg o.d. Versus 40 mg b.i.d. A Randomized Clinical Trial [Internet]. clinicaltrials.gov; 2020 May [cited 2020 May 28]. Report No.: NCT04366960. Available from: https://clinicaltrials.gov/ct2/show/NCT04366960
Blondon M. Preventing COVID-19-associated Thrombosis, Coagulopathy and Mortality With Low- and High-dose Anticoagulation: A Randomized, Open-label Clinical Trial [Internet]. clinicaltrials.gov; 2020 Apr [cited 2020 May 28]. Report No.: NCT04345848. Available from: https://clinicaltrials.gov/ct2/show/NCT04345848
Parikh SA. Intermediate or Prophylactic-Dose Anticoagulation for Venous or Arterial Thromboembolism in Severe COVID-19: A Cluster Based Randomized Selection Trial (IMPROVE-COVID) [Internet]. clinicaltrials.gov; 2020 May [cited 2020 May 28]. Report No.: NCT04367831. Available from: https://clinicaltrials.gov/ct2/show/NCT04367831
Panigada M, Bottino N, Tagliabue P, Grasselli G, Novembrino C, Chantarangkul V, et al
. Hypercoagulability of COVID-19 patients in intensive care unit. A report of thromboelastography findings and other parameters of hemostasis. J Thromb Haemost 2020. doi: 10.1111/jth.14850.
Canelli R, Connor CW, Gonzalez M, Nozari A, Ortega R. Barrier enclosure during endotracheal intubation. N
Eng J Med 2020;382:1957-8.
Bauer M, Bernstein K, Dinges E, Delgado C, El-Sharawi N, Sultan P, et al
. Obstetric anesthesia during the COVID-19 pandemic. Anesth Analg 2020;131:7-15.
Franks WLM, Crozier KE, Penhale BLM. Women's mental health during pregnancy: A participatory qualitative study. Women Birth 2017;30:e179-87.
Khalid I, Khalid TJ, Qabajah MR, Barnard AG, Qushmaq IA. Healthcare workers emotions, perceived stressors and coping strategies during a MERS-CoV outbreak. Clin Med Res 2016;14:7-14.