Specialized Expertise of the Intensive Care Unit Physical Therapist

Effective clinical decision making and practice in the ICU demand specialized expertise and skill, including advanced, state-of-the-art knowledge in cardiovascular and pulmonary and multisystem physiology and pathophysiology and in medical, surgical, nursing, and pharmacological management (Box 33-1). Physical therapists in the ICU need to be first-rate diagnosticians and observers. Given the multitude of factors that contribute to impaired oxygen transport,⁶ the physical therapist needs to analyze these to define the patient’s specific oxygen transport deficits and problems. Optimizing oxygen delivery in the patient who is critically ill⁷ by exploiting noninvasive interventions is the priority.

Box 33-1   Specialized Expertise and Skill of the Intensive Care Unit Physical Therapist

 Detailed, comprehensive knowledge of cardiopulmonary physiology and pathophysiology and pharmacology.

 Thorough working knowledge of the monitoring systems routinely used in the intensive care unit (ICU) and an understanding of the interpretation of the output of these monitoring systems (e.g., electrocardiogram [ECG], arterial blood gases, fluid and electrolyte balance, hemodynamic monitoring, chest-tube drainage systems, intracranial pressure monitoring). This information is an integral component for assessing the underlying problems and selecting, prioritizing, and progressing or modifying treatment.

 Extensive expertise in cardiopulmonary assessment and treatment prescription; general experience in medicine and surgery is recommended.

 Detailed understanding of multisystem physiology and pathophysiology and the cardiopulmonary manifestations of systemic disease.

 Ability to practice effectively under pressure and in congested, suboptimal working conditions.

 Knowledge regarding all emergency procedures, including those for respiratory and cardiac arrest, equipment problems, and power failure.

 Knowledge regarding the paging system used in the unit for being contacted as well as for contacting other team members when they are out of the unit or out of the hospital.

 On-call service, 24 hours a day, 7 days a week, is a common practice and should be considered in units without this service.

 Knowledge regarding the roles of all team members.

 Sensitivity toward each patient’s psychosocial situation, culture, and values and promotion of active involvement of the patient and family in clinical decision making, whenever feasible.

 Superior communication skills (e.g., ability to work cooperatively with other members of the ICU team [Figure 33-3] and give verbal presentations and discuss patients at rounds).

The role of the ICU physical therapist is to promote healing and recovery and to return the patient to the highest possible level of life participation and satisfaction. Therefore the physical therapist must be capable of processing considerable amounts of objective information quickly, interpreting this information, and integrating it to provide the basis for a treatment prescription (i.e., the specific selection, prioritization, and implementation of treatment interventions). The ability to integrate and interpret the vast amount of multiorgan system data is perhaps the single most important skill in ICU practice and treatment prescription. With these data the physical therapist identifies the indications for treatment, contraindications, and optimal timing of interventions. The condition of the patient in the ICU can change rapidly. The physical therapist works within narrow windows of opportunity to effect an optimal treatment response. Treatments are variable with respect to their intensity, duration, and frequency. The maximally beneficial outcome with the least risk to the patient is the objective of every treatment. Although principles of management may be the same, specific knowledge requirements will differ depending on the type of critical care setting (e.g., burn, coronary care, neurosurgery, spinal cord injury, and trauma). Alternatively, a community hospital with a small general ICU will have a cross section of patients that the physical therapist will need to manage.

Goals and General Basis of Management

The ultimate goals of cardiovascular and pulmonary physical therapy in the ICU include the following:

As precursors to achieving these goals, the immediate goals relate initially to maximizing oxygen transport, hence, cardiovascular and pulmonary function; and second to maximizing musculoskeletal and neurological function. In the ICU the physical therapist needs to recognize the implications of cardiovascular and pulmonary insufficiency on neuromuscular status and that apparent impairment of neuromuscular status is not necessarily indicative of neurological dysfunction. Rather, reduced cardiac output and blood pressure, hypoxemia, hypercapnia, and increased intracranial pressure (ICP) may be responsible for these changes indirectly. Musculoskeletal and neurological complications can become life-threatening and therefore need to be detected early and managed.

Key elements of the assessment of the patient in the ICU include risk factors for a suboptimal clinical outcome. In addition to age and comorbidity, risk factors include poor indices of PaO₂ with a high FIO₂, platelet count, cardiac index, blood urea nitrogen, creatinine, and renal function. Other risk factors include peritoneal dialysis or hemodialysis, continuous infusion of antidysrhythmic agents, base deficit, reduced consciousness, pain, and cardiac arrest. Thus patients with one or more of these risk factors, conditions and interventions, require close monitoring and management.

Many elements of the assessment of patients in the ICU are comparable to those for patients with acute conditions who are not critically ill but require respiratory support and mechanical ventilation (see Chapter 44). The primary difference is that for patients in the ICU the adequacy of the steps in the oxygen transport pathway are monitored closely, and the status and function of multiple organ systems are monitored in a serial (repeated at regular or judicious intervals) manner to observe trends over time so that treatment modifications can be titrated to the patient’s responses. Serial vital signs including pain and distress are recorded along with arousal and cognitive status, neuromuscular status, musculoskeletal status, and functional mobility. Assessment of functional mobility ranges from the smallest movement to walking (see Figure 33-2 and Box 33-4). Often it includes bed mobility, transfers to chair, and walking, which may require assistive devices. Related laboratory investigations are noted, including the electrocardiogram (ECG), radiographs, scans, blood work, blood sugar level, and fluid and electrolyte balance, and are followed closely to quickly detect improvement or deterioration so that treatment can be correspondingly modified.

Mechanical ventilation and its modes and parameters are described in Chapter 44. The ventilator settings including the fraction of inspired oxygen (FIO₂) are important indicators of changes in the patient’s status and therefore must be included in the assessment and recorded at each treatment. Similarly, changes in FIO₂ are important outcomes and indicators of treatment response. This information is used collectively in clinical decision making before, during, and after weaning from mechanical ventilation.

In patients who are medically stable, invasive mechanical ventilation is titrated judiciously to ensure that the patient is initiating breaths as much as possible, which facilitates weaning. Depending on the patient’s response to ventilation, however, sedation and neuromuscular blockade may be indicated. These interventions limit the patient’s capacity to cooperate fully with treatment. Breathing patterns imposed by the mode of mechanical ventilation influence venous return and aortic pressures⁸; thus mobilization needs to be prescribed accordingly. Furthermore, weaning patients with chronic obstructive pulmonary disease (COPD) and neuromuscular conditions is complicated by respiratory muscle weakness and fatigue (see Chapter 26), which may indicate respiratory muscle training or rest. Because of these challenges, weaning necessitates close cooperation and coordination within the team to maximize weaning success.

As for patients who are not critically ill, the assessment data are evaluated, problems and diagnoses made, and interventions prescribed based on the patient’s needs and goals. Physical therapy has a prominent role in the management of patients who are on mechanical ventilation.9,10 With each treatment, the responses are reviewed and prescription parameters of the interventions are refined to progress the patient

Specificity of Cardiovascular and Pulmonary Physical Therapy

Physical therapy interventions in the ICU (see Chapter 17 and Part III) are more specifically geared toward the status of each organ system, taking into consideration the pathophysiological basis for the patient’s signs and symptoms, the rationale for each intervention, and the physiological and scientific evidence supporting the effectiveness of the intervention.¹⁴ Physical therapy provides both prophylactic and therapeutic interventions for the patient in the ICU. Conservative, noninvasive measures constitute initial treatments of choice to avert or delay the need for additional invasive monitoring and treatment including supplemental oxygen, pharmacological agents, and the need for intubation and mechanical ventilation. The physical therapist aims to avoid, reduce, or postpone for as long as possible the need for respiratory support. Even if the patient is mechanically ventilated, maintaining some level of spontaneous breathing, no matter how minimal, is associated with improved oxygenation and outcomes.¹⁵ In addition, the physical therapist helps to prevent the multitude of side effects of restricted mobility and recumbency during bed rest. A summary of general information required before treatment of the patient in the ICU is presented in Box 33-3. This provides the basis for establishing a patient’s readiness to be mobilized and the progressive steps for doing so (Box 33-4 and Figure 33-2).

Box 33-3   General Information Required before Treatment of the Patient in the Intensive Care Unit

 Sex and age

 Premorbid status (e.g., lifestyle, ethnicity, culture, work situation, stress, cardiopulmonary conditioning, and oxygen transport reserve capacity)

 Knowledge of patient’s life roles and related activities for optimal return to daily life

 Medical and surgical histories

 General multisystem assessment findings

 Pharmacological support

 Smoking history

 Hydration and nutritional status: deficiencies, obesity, or asthenia

 Time of onset and course of present condition

 Existing or potential medical instability

 Indications or necessity for intubation and mechanical ventilation

 Mode and parameters of mechanical ventilation

 FIO₂

 Invasive monitoring, lines, leads, and catheters

 Existence of or potential for complications and multiorgan system failure

 Cognition or coma scale score

 Presence of elevated intracranial pressure (ICP) and the need for ICP monitoring

 Risk or presence and site(s) of infection

 Quality of sleep and rest periods

 Nutritional support during intensive care unit stay

 Pain control regimen

Box 33-4   Guiding Principles for Mobilizing Patients in the Intensive Care Unit

Based on a multisystem assessment and discussion with the team:

 Determine the patient’s readiness for mobilization—that is, perform multisystem assessment including arousal, medications, lines and leads, mechanical ventilation and respiratory support; responses to gravitational and mobilization challenge tests; contraindications and precautions and clearance by team.

 Establish therapeutic and safe parameters for a given patient based on objective and subjective measures.

 Prescribe the parameters of the gravitational and mobilization stimuli (types of mobilization and exercise, their intensities, duration, and frequencies) by titrating them to the patient’s immediate and longer term responses (see Fig 33-2 for progression of mobilization). Principles for progressing the mobilization stimulus:

 Progression to successive steps is based on the patient’s responses.

 If the patient’s physiological responses change appropriately and commensurately with the increment in mobilization load and the patient’s condition remains stable, then the next step may be attempted.

 If untoward responses occur, then the patient can return to the previous level or potentially to sitting or supine to regain resting status.

 The patient is reassessed before each bout of mobilization and evaluated throughout and afterward.

 Monitor the patient during and after each of the levels shown in the following schema, and record the responses and outcomes.

 Progress patient:

 Increased intensity. Increase is commensurate with reduction of support and assistance, and increased duration to increase volume of exercise overall, and with improvement—that is, the patient tolerates greater gravitational stress and exercise stress with reduced physiologic demands within therapeutic and safe limits)

 With increased intensity and increased duration, frequency of the mobilization sessions may be reduced.

 Some patients quickly progress through these steps, and others progress more slowly based on their individual responses.

 Monitor response to recovery and rest and qualitative and quantitative evaluation of return to resting baseline.