To the Editor:
We read with great interest the manuscript by Greenland et al., discussing the perioperative and critical care implications of coronavirus disease 2019 (COVID-19) infection with a focus on management of associated respiratory failure.1 We congratulate the authors for the comprehensive article which is imperative in these times for the critical care physicians.
The authors have discussed the typical presentation enumerating the primary presenting symptoms, major complications, and variations in presentation. However, we would like to add to this list an important aspect of involvement of the central nervous system. In a recent case series of 214 patients, about 36.4% (78 of 214) of the patients had neurologic manifestations pertaining to the central and peripheral nervous systems and skeletal muscle injury.2 The patients who had severe infection were prone to develop neurologic manifestations. The symptoms observed were dizziness, headache, seizures, impaired consciousness, acute cerebrovascular disease, and ataxia. The loss of smell and taste seen in these patients indicates the possible involvement of the peripheral nervous system by the virus. The transsynaptic transfer from peripheral to central nervous system is quite a possibility. The neurotropism of this novel coronavirus is believed to be similar to other coronaviruses.3 The report of acute necrotizing encephalopathy affecting the thalamus, brain stem, white matter, and cerebellum strongly indicates the involvement of the nervous system by this novel virus.4 The cytokine storm implicated in COVID-19 infection may cause breakdown of the blood–brain barrier causing inflammation, edema, encephalitis, and meningitis. The detection of the virus in cerebrospinal fluid, instead of via nasopharygeal swab, indicates the need for high suspicion of COVID-19 infection in all patients presenting with altered sensorium and neurologic symptoms.5 The involvement of the brainstem and vital centers might possibly be an important reason for respiratory failure and the number of unexplainable deaths seen worldwide.3 Another reason for high fatality may possibly be due to unrecognized pulmonary thromboembolism. The observed increase in D-dimer seen in these patients, can be due to cytokine storm, sepsis and procoagulable state. Patients may present with thromboembolic complications or develop them despite the use of anticoagulant prophylaxis. Studies have found that about 8 to 15% developed arterial/venous thromboembolic complications.6,7 The incidence of acute cerebrovascular manifestation is about 5.7%, with ischemic stroke observed to be 2.5 to 5%.6
Thus, neurologic manifestations as the primary presenting symptom are quite common in COVID-19 infection. A high index of suspicion in such patients may help avoid delay in diagnosis and catastrophic sequelae.
The authors declare no competing interests.