Focused Management of Patients With Severe Acute Brain Injury and ARDS

Abstract

Considering the COVID-19 pandemic where concomitant occurrence of acute respiratory distress syndrome (ARDS) and severe acute brain injury (sABI) has increasingly co-emerged, we synthesize existing data regarding the simultaneous management of both conditions. Our aim is to provide readers with fundamental principles and concepts for the management of sABI and ARDS, and highlight challenges and conflicts encountered while managing concurrent disease. Up to 40 percent of patients with sABI can develop ARDS. While there are trials and guidelines to support the mainstays of treatment for ARDS and sABI independently, guidance on concomitant management is limited. Treatment strategies aimed at managing severe ARDS may at times conflict with the management of sABI. In this narrative review, we discuss the physiological basis and risks involved during simultaneous management of ARDS and sABI, summarize evidence for treatment decisions, and demonstrate these principles using hypothetical case scenarios. Use of invasive or non-invasive monitoring to assess brain and lung physiology may facilitate goal-directed treatment strategies with the potential to improve outcome. Understanding the pathophysiology and key treatment concepts for co-management of these conditions is critical to optimizing care in this high-acuity patient population.

Mechanical ventilation in acute brain injury patients with acute respiratory distress syndrome

“…Torre et al in their review article, addressing management of ARDS in TBI patients, concluded that LPV is not an absolute contraindication in neurological patients ( 28 ). Individualized approach using ICP monitors may be needed in patients to set PCO 2 goals in cases of elevated ICP and ARDS ( 31 ).…”

“…Hyperoxia (>200 mmHg) is also associated with higher mortality and worse short-term functional outcomes in TBI ( 32 ). A recent review article addressing management of ARDS in severe ABI also recommended higher PO2 targets of >110 mmHg if allowed from a lung compliance perspective ( 31 ). Thus, for ABI patients with ARDS, it may be reasonable to use a higher PO 2 goal than what has been recommended in ARDS patients without ABI (55–80 mmHg) ( 6 , 28 , 31 ).…”

“…A recent review article addressing management of ARDS in severe ABI also recommended higher PO2 targets of >110 mmHg if allowed from a lung compliance perspective ( 31 ). Thus, for ABI patients with ARDS, it may be reasonable to use a higher PO 2 goal than what has been recommended in ARDS patients without ABI (55–80 mmHg) ( 6 , 28 , 31 ). Oxygen targets may be modified in settings where brain tissue oxygen (PbtO 2 ) monitoring is available, understanding that there is no high-quality data on the outcome benefit of PbtO 2 in patients with ICP crisis.…”

“…Increasing PEEP elevates the intrathoracic pressure, causing a decrease in the cerebral venous return, which may subsequently increase ICP ( 31 ) ( Figure 1 ).Given this possible effect on ICP, use of high PEEP and recruitment maneuvers is contentious in the neurocritical care field ( 28 ).…”

Controversies and evidence gaps in the early management of severe traumatic brain injury: back to the ABCs

“… 41 A challenge arises when trying to maintain a ‘brain-lung balance’; Kim et al comprehensively review the evidence and demonstrate several cases where there was an obvious brain-lung conflict and how they were managed. 42 Providers can use high tidal volumes to maintain normoxia and mild hypocapnia with low levels of positive end-expiratory pressure (PEEP) to preserve CBF and reduce impedance to cerebral venous return via increases in intrathoracic pressure. On the other hand, many of these patients are prone to develop post-traumatic acute respiratory distress syndrome (ARDS) that requires a lung-protective ventilation strategy.…”