To our knowledge, this study is the most extensive multisymptom assessment of a heterogeneous group of ICU patients at high risk of dying. Symptom assessments were done at least once on 171 (69%) of 245 patients with an average of three assessments per patient during their ICU stay regardless of whether or not the patient was mechanically ventilated. During 50–75% of the patient assessments, patients reported being anxious, thirsty, and tired.
Anxiety was more common in patients who were mechanically ventilated when providing symptom reports. These higher rates of anxiety may be partially attributable to mechanically ventilated patients' inability to verbally communicate their concerns or to seek information about their condition (21
). In fact, in one study (22
), 85% of 106 mechanically ventilated patients reported some anxiety, and 69% of the anxiety reports were rated moderate to severe. Taken together, these consistent findings suggest that clinicians need to perform systematic assessments of anxiety, especially in mechanically ventilated patients, and consider using both pharmacologic and nonpharmaco-logic interventions to decrease this distressing symptom (21
Thirst was the second most common and the most intense symptom in these patients. Thirst was identified in survey research (23
) as one of the greatest stressors for ICU patients. However, this symptom is not routinely assessed in ICU patients and, when it is, it may be ignored because there is a perception that nothing can be done to address it. In fact, in a recent qualitative study, whereas 20 ICU nurses identified reasons why patients could be thirsty (for example, dehydration, hypernatremia), approximately half of them did not perceive that mechanically ventilated patients could be thirsty (25
). Few strategies were recommended by the interviewed nurse to reduce thirst, and none of the nurses reported developing a plan of care to relieve thirst. Given the high prevalence and intensity of thirst in this sample, additional research is warranted on the most effective interventions to prevent or decrease thirst.
The vast majority of patients (75%) reported being tired. This finding is not unexpected because sleep deprivation and abnormal sleep–wake cycles are known to occur in ICU patients (26
). However, because sleep was not a focus in this study, the relationship between patients' reports of being tired and their sleep status is unknown. Many other factors associated with their illness such as noise and lights in the ICU environment, frequent awakenings, or medications received could make ICU patients tired (26
An unexpected finding is that patients reported pain during only 40% of the assessments, and pain was of mild to moderate intensity. This finding is similar to findings from two other recent ICU studies. In an observational study in 44 ICUs in France, up to 51% of 1381 mechanically ventilated patients had substantial nonprocedure-related pain (27
). In another study, the incidence of pain in 230 ICU patients when they were at rest was found to be 38% (28
). It is possible that patients who responded in our study were receiving the appropriate dose of analgesics, which supports the titration of analgesics to patients' pain reports. At a more general level, this finding may reflect the increased emphasis given to pain assessment and treatment for ICU patients over the past 10 yrs.
Although pain prevalence in the current study was only 40%, pain distress was moderate to severe. This finding confirms that pain is multidimensional and requires clinicians to attend to both its sensory (that is, intensity) and affective (that is, distress) dimensions. Subsequent treatments could target one or both of these pain dimensions, depending on their severity. Balancing effective pain management with clinical outcomes is important because recent data suggest that patients are discharged from the ICU sooner when sedating medications are interrupted on a daily basis (29
). Pain intensity can be treated with judicious use of an analgesic vs. sedative medications. Pain distress may be more amenable to nonpharmacologic interventions such as music, relaxation, and information in conjunction with analgesics, yet these approaches have not been systematically studied in ICU patients.
Consistent with a previous review (30
), in approximately 30% of the assessments, patients reported sadness and fear. In fact, being scared was the second most distressful symptom. Similar to the discussion of anxiety, it is not surprising that patients were fearful in an ICU environment and perhaps fearful about their outcomes. In fact, ICU patients have reported fear associated with mechanical ventilation (31
), monitors (30
), “coming down off all the drugs,” and death (22
). Findings across these studies suggest that ICU patients should be assessed for the presence and intensity of fear and that appropriate interventions need to be implemented. Anticipation of patients' needs, clear communication practices, and use of caring behaviors can help to alleviate stress and fear. In addition, family members can provide patients with information, explanations, encouragement, and perform relaxation techniques to decrease anxiety and fear (22
Dyspnea (termed shortness of breath in this study) was the most distressing symptom. Although dyspnea often precipitates the use of mechanical ventilation (32
), no differences were found in dyspnea intensity or distress ratings reported by patients who were vs. were not mechanically ventilated. Although previous studies found that patients on mechanical ventilation experienced dyspnea (3
), the pathophysiological mechanisms for, and iatrogenic sources of, dyspnea warrant additional investigation. Given that dyspnea was the most distressful symptom in this sample, clinicians need to perform routine assessments for dyspnea, especially in mechanically ventilated patients. This subjective assessment could be done in conjunction with objective assessments (for example, ventilator settings, arterial blood gases, assessment of mechanics of respiration) that are performed on a routine basis for mechanically ventilated patients. This study did not include documentation of the method of ventilatory support (for example, mandatory ventilation or pressure support ventilation) or its impact on dyspnea. An assessment of the impact of the mode of ventilation might provide important insights into optimal management strategies to address dyspnea.
Delirium was present in approximately 34% of the patients who were able to be assessed, which is consistent with previous studies (4
). However, some patients could not complete the delirium assessment and, therefore, hypoactive delirium may have been missed. The prevalence of delirium was associated with higher daily dose of opi-oids, a finding consistent with previous reports (6
). However, unlike those reports, this study did not have enough CAM-ICU-tested patients who received benzodiazepines to determine a relationship between delirium and use of benzo-diazepines. Attention needs to be paid to the symptom of delirium because of its adverse effect on ICU patient outcomes. Delirium assessments need to be done on a routine basis. However, we were able to perform a delirium assessment after only 80% of the symptom assessments (that is, 325 of 405 assessments) because patients were not able to follow directions or to continue with the delirium assessment after the symptom assessment, most often as a result of fatigue. Every effort should be made to complete delirium assessments using the CAM-ICU or another valid and reliable assessment instrument like the Intensive Care Delirium Screening Checklist (38
). If delirium assessment is still impossible, there should be a high index of suspicion that a patient may have delirium. Attention to patients' behaviors and responses, or lack of responses, to questions may help to determine whether delirium is present.
Although research on delirium in ICU patients has increased dramatically in the past 8 yrs (4
), no studies were found that examined the relationship between delirium and other symptoms. In this study, a higher number of delirious vs. nondelirious patients reported confusion and sadness, but fewer delirious vs. nonde-lirious patients reported being tired. Providing patient reassurance, information, and frequent reorientation of the patient to the ICU environment may ameliorate some of the confusion. In some cases, medications may contribute to the delirium. As a result, opioids and benzodiazepines should be used judiciously, titrating their doses to patient need and effect while assessing the potential onset of disturbing symptoms like delirium. At the same time, one must be cautious in balancing the patient's need for analgesics with concerns that the therapy may increase the likelihood of delirium.
Why fewer of the patients in this study with delirium were tired than those without delirium is unknown and inconsistent with previous studies that found a positive association between sleep deprivation and delirium (26
). Further studies are needed to confirm these findings and to evaluate the influence of sedatives and analgesics on tiredness. Another finding that warrants further study is the relationship between delirium and sadness. It may be that the patients' delirious thoughts were ones that caused sadness. However, our results cannot be seen as causal and cannot be explained without further investigation. Findings could be the result of confounding factors because patients in the delirious vs. not delirious groups may have differed on other important characteristics.
Several study limitations need to be acknowledged. First, only 10% of the possible 1273 patients screened met eligibility criteria, and only 69% of them (that is, 171) were able to report their symptoms on at least one of seven possible assessments. Furthermore, because some patients who reported their symptoms to be present were unable to rate the symptom's intensity or distress, missing data reduce the generalizability of the findings. Indeed, the presence of missing data reflects the severity of illness of these patients and suggests that clinicians need to assess for at least the presence of symptoms and address symptom intensity and distress whenever possible. Another limitation is that this study assessed symptoms in a subset of ICU patients, which limits the generalizability of the findings to patients with different levels of acuity, different underlying clinical conditions, or different institution, yet given the prevalence rates, intensity, and distress of symptoms found in these patients, symptom assessments should become a routine part of patient assessments whenever possible.
Of note, only 34% of mechanically ventilated patients responded to the symptom assessments. Hence, it is possible that we could be underreporting the true prevalence of these distressing symptoms in our mechanically ventilated patients, yet the 34% of mechanically ventilated patients completed 138 (out of 405) symptom assessments, providing us with more information about mechanically ventilated patients' symptoms than ever previously reported.