30 Jun 2020

The post-ICU syndrome of COVID19


Staying in intensive care units (ICU) is saving more and more lives. Advances in medical knowledge and the technology available in these services allow the survival of many more people. However, this outcome is not without some difficulties, particularly those which can be grouped under so-called Post Intensive Care Syndrome (or PICS), first described in 2012 (Needham et al). The long hospitalizations in intensive care units that many patients have had to undergo due to the COVID-19 pandemic have highlighted the rehabilitation needs of those with post-ICU syndrome.

PICS is characterized by the appearance of physical difficulties (pain, weakness, etc.), cognitive disturbances (attention difficulties, memory and slow information processing) and emotional problems (such as anxiety, low mood, the possible appearance of post-traumatic stress). These difficulties can occur during the stay in the ICU, after discharge and, in many cases, in the medium and long term after admission.

Marcos Ríos Lago, Brain Injury Unit Coordinator at Beata María Ana Hospital

According to Ohtake et al. (2018), throughout the first year after admission to the ICU, these patients present difficulties collected in the three domains of the International Classification of Functioning (CIF), which include alterations in body functions and structures, limitations in activity and limitations in participation. This implies serious difficulties in carrying out basic and instrumental activities of daily life, as well as problems in returning to driving or keeping employment, affecting quality of life and return to normal activity.

Physical disturbances

From a physical point of view, Lane-Fall et al. (2018) point out that muscle weakness is very frequent. This is more pronounced the longer the ICU stay and tends to affect skeletal muscles more than smooth muscles. Furthermore, this weakness is also observed in the oropharyngeal musculature, which seems to be related to the dysphagia problems that are observed. The situation of mechanical ventilation and the possibility of a tracheostomy are also related to these swallowing difficulties.

The most frequent physical disorders are:

  • muscle weakness
  • loss of muscle mass, generally symmetrically in the two hemibodies
  • difficulties in walking
  • low exercise tolerance
  • respiratory deterioration
  • swallowing problems
Cognitive disturbances

Regarding cognitive performance, at the time of discharge from the ICU, cognitive disturbances can affect 70-100% of patients. One year later, between 46-80% still suffer from this decrease in performance, and 20% retain these difficulties 5 years after admission to the ICU (Sheehy et al., 2020). Possible causes of persistent deterioration after admission could be hypoglycemia, hyperglycemia, or fluctuations in serum glucose during this period, according to Inoue et al. (2019). This study also points to the influence of the presence of delirium and acute stress during hospitalization.

All the components of cognition may be affected to a greater or lesser extent, but attentional difficulties, alterations in visuospatial abilities, memory (including working memory) and executive functions stand out. There is great variation between patients, which would require a specific assessment of each person (Sheehy et al., 2020). This assessment must consider what is the impact on daily life and quality of life of the possible difficulties that the individual presents.

Some authors point out that, three months after being discharged from the ICU, 40% of patients show a cognitive performance equivalent to that of a patient who has suffered a moderate traumatic brain injury, and 26% of patients show performance similar to that of a person with a diagnosis of mild Alzheimer’s. Furthermore, this low performance frequently persists 12 months after discharge, maintaining equivalent yields in between 24% and 34% of patients. These alterations occurred in all age ranges (Pandharipande et al., 2013; Sheehy et al. 2020), and can be both new to occur or present in the form of aggravation of pre-existing characteristics and difficulties.

It should be noted that from a rehabilitative point of view, difficulties with orientation, attention, memory and processing speed have shown a good response to cognitive stimulation programs. However, changes in executive functions require more complex intervention programs (Lane-Fall et al. 2016).

In summary, it can be pointed out that the most frequent cognitive alterations are:

  • memory disturbances
  • attention problems
  • slow processing of information
  • delirium
  • confusional states
  • presence of hallucinations
  • disturbances of executive functions
Emotional disturbances

Most of the patients report having experienced a severe rupture of everyday life, in which high-intensity emotional symptoms appear for which they were not prepared. Furthermore, it should be noted that this is not an imagined situation. Quite the contrary, the fear is intense and real. Some reactions may be associated with the physiological correlate of sedation or mechanical ventilation, increasing the level of catecholamines and thus anxiety, agitation and even a feeling of terror. If possible movement limitations are added to this (sometimes restricted for the patient’s safety), these feelings can increase. For this reason, and to minimize the impact of ICU admission, improvements in protocols are being considered, such as better management of sedation (in favour of intermittent or minimal sedation).

After hospitalization in the ICU, adverse emotional effects have been described. Depression (30%), anxiety (70%) and post-traumatic stress disorder (PTSD; 10-50% of cases) are the main mental illnesses associated with PICS. Even two years after admission, some patients show PTSD (22% -24%), depression (26% -33%), and generalized anxiety (38% -44%) (Sheehy et al., 2020). It may also be common to relive ICU images in the form of intrusive memories, night terrors, or nightmares, even after discharge. The widespread belief that patients do not remember what happened in the ICU seems not to be true since up to 88% of these people present these undesirable memories. All this implies a serious reduction in the quality of life, worse daily functioning, a longer disability time and an increase in the costs of medical care.

The appearance of sleep disorders can also be emphasized as relevant. Sometimes it is the consequence of the alteration of the normal cycles of sleep and wakefulness, and it may be one of the first signs that are indicating the presence of PICS.

Finally, post-traumatic stress disorder deserves a specific mention since it affects between 10 and 39% of patients after the ICU. Perhaps it is the best-identified component of those presented in the PICS. This may appear after a threatening event or a perception of a lack of security. The main problem with PTSD is the possibility of the persistence of symptoms in the very long term (even 14 years after the traumatic event). For this reason, it is important to identify it and teach the patient management and coping strategies that minimize the impact of this situation.

Among the risk factors for the appearance of these difficulties are the existence of previous psychiatric illnesses, the appearance of symptoms during the hospitalization period, being young, female, not having a job, consuming alcohol and the use of sedation with opiates during the ICU period (Inoue et al., 2019; Sheehy et al., 2020).

In summary, the most frequent emotional disturbances are:

  • depression
  • anhedonia
  • anxiety
  • post-traumatic stress (PTSD)
  • sleep disorders

Other specific forms: family and pediatric patients

Finally, this situation is not exclusive to adults. Two specific forms of PICS have been described: PICS-f, applicable to the families of the patients, and PICS-p, specific to pediatric age.

The additional appearance of difficulties in the family (PICS-f) implies anxiety (70%), depression (35%), post-traumatic stress (35%) and other problems such as fatigue, increased risk behaviours, problems with sleep or eating disorders, among others. These can also be persistent and extend beyond the year (Inoue et al., 2019; Torres et al., 2017). Torres also maintains that the care of a post-critical patient affects life plans, social relationships, professional performance and may result in the appearance of family conflicts. Some of these difficulties do not appear suddenly in the acute phase, but progressively develop and acquire a clinically relevant character throughout the first weeks or months after discharge from the ICU, which may also be associated with a difficulty managing new caregiver roles (Sheehy et al., 2020).

In 2018, pediatric PICS (PICS-p) was described. Post-ICU syndrome in boys and girls is very similar to that suffered by adults, but implies a greater understanding of the impact of difficulties in different age ranges. Thus, it is necessary to optimize evaluation and detection procedures that allow the implementation of intervention programs that are also specific.

Interest in post-ICU treatment and possibilities of rehabilitation

Considering the high prevalence of these disorders, it seems reasonable that all patients who have undergone ICU admission be evaluated to rule out the presence of any of the difficulties described. Upon detection of alterations, it is possible to start a rehabilitation program to recover the affected functions and, in any case, minimize the impact of the difficulties detected. There are therapeutic options for each of the problems described that have shown effectiveness in other types of patients (stroke, TBI, etc.).

This approach must be multidisciplinary. After evaluation and the potential detection of symptoms, a follow-up will be necessary, which involves a physical and a psychological, cognitive and family functioning review. Psychological or psychiatric treatment should be started as soon as possible after discharge if any symptoms are detected in the patient.

It seems clear that the early start of a rehabilitation process improves physical performance in the short term (Fuke et al., 2017). Some interventions have also decreased the probability of PTSD onset, such as the “simple” preparation of a diary during admission (prepared by the nursing team and the family, recording daily what happened during the ICU stay, with simple language and with photographs that illustrate it -Fuke et al., 2017-).

Other authors propose the integration of a neuropsychology professional in the ICU team (Dodd et al., 2018). However, it is not so clear that immediate attention, if it is limited to the phases in the ICU, serves to minimize the impact in the medium and long term, so that post-discharge rehabilitation processes may be necessary. In this sense, the work with neuropsychologists during the post-acute phase and in the medium and long-term follow-up have shown high levels of satisfaction of affected people and family members, improving care and well-being (Dodd et al., 2018). For Merbitz et al. (2016). It is important to understand the complexity of the post-ICU situation and intervene both in deficits (trying to restore previous performance) and in issues of an emotional and relational nature (roles, family, etc.), as well as in the familiar surroundings.

Final thoughts

All the physical, cognitive and emotional disorders described are deep and lasting. The impact can be very high and generate consequences that are incompatible with an adequate social, family and work life.

During the initial phases of ICU admission, current literature is showing attempts to optimize procedures inpatient care, pain reduction, sedation management, optimization of sounds and lights of patient monitoring equipment, the inclusion of physiotherapy and cognitive treatment, as well as an increase in follow-up times by families.

However, these procedures are not generalized, and it is necessary to monitor and care for these people after discharge from the ICU. There is a clearly identified opportunity to address the care needs of patients with PICS, but they must be identified, evaluated, and multidisciplinary treatments initiated that do not focus on a single aspect of the syndrome, ranging from the most physical components to the need to listen and understand.

Lastly, PICS has been only recently detected (2012) but it has become especially relevant in recent months, when the number of ICU admissions has been increased by the Covid-19 pandemic. Although the difficulties associated with Covid-19 deserve a specific article, it should be pointed out that many of the alterations described here have also been observed as symptoms and disorders present after admission for Covid-19. This disease is currently being intensively researched and we will surely have detailed descriptions that characterize it. However, it is likely that, in those hospitalized patients, the difficulties associated with PICS exist and should be considered.

Marcos Ríos Lago, Brain Injury Unit Coordinator at Beata María Ana Hospital (Madrid, Spain)