Alix O. Paget-Brown and Robert A. Sinkin

Initiation of the ICU Transport

The trauma patient needs immediate stabilization and blood loss/fluid and airway management. The ICU patient, in contrast, is usually a study in physiology, requiring sometimes-complex airway and medication management. ICU patients can vary in their level of stability at the time of transport.

The single most important part of the ICU patient transport is the handing off of care between providers. The history provided by the current providers, both physician and nurse or physician extender, is key. Knowing the underlying diagnosis(es) and obtaining a current and accurate list of medications and infusions (including timing and dosing) are essential to care for the patient correctly during transport. Any unusual aspects in managing an individual patient should also be mentioned at this time (e.g., an older adult with a paradoxical agitation response to midazolam as opposed to sedation).

The Airway in Transporting the ICU Patient

Management of the medically ill ICU patient’s airway can be especially complex. For those patients already mechanically ventilated, maintenance of the airway provides both advantages and significant challenges.

Certainly, having a stable airway in a mechanically ventilated patient is an advantage. However, whether the patient is ventilated via endotracheal or tracheotomy tube, ensuring that the tube is securely taped or attached and well positioned may be difficult. Transporting a patient inevitably requires several patient movements, on and off of stretchers, and even further shifting the patient several times if the transport is for additional testing. The security of the airway at all times is vital. A chest radiograph obtained immediately prior to transport gives the team confirmation of initial placement. Further confirmation of security/stability and placement should be performed after every movement. This comprises an assessment of the security and depth of the tube, as well as auscultation to ensure symmetric breath sounds (see Table 112.E1 for appropriate endotracheal tube sizes and depths). Adequate sedation during transport aims to prevent the patient from dislodging the tube or becoming agitated or combative (see Chapter 5). Continuous pulse oximetry should be maintained during transport to aid in assessment of the airway and adequate oxygenation during transport.

Transporting the mechanically ventilated patient requires switching to a transport ventilator, the majority of which are conventional mechanical ventilators. The simplest transport device offers limited modes of support, whereas more complex devices offer a variety of ventilation modes, such as intermittent mandatory ventilation (IMV), assist control, or a combined assist/control mode with pressure or volume control (see Chapter 2). For patients on a conventional mechanical ventilator, a direct switch using the current ventilator settings can often be easily accomplished. However, switching from a more complex mode (e.g., high-frequency ventilation) to a transport ventilator may require a period of stabilization/transition (discussed later). An arterial blood gas (ABG) on the new ventilator at the current settings should be evaluated to address any ventilation needs prior to transport. For prolonged transports to other facilities, ABGs should be checked periodically, ideally every 1 to 2 hours if the patient appears clinically stable and more often if unstable. Ventilator adjustments should be performed gradually, avoiding sudden shifts, but providing the needed support. Any large ventilator changes to combat severe respiratory acidosis and hypercapnia should have blood gases monitored every 30 minutes until stable. Even appropriate blood gases after significant ventilator manipulation must be followed up, as overcorrection and subsequent hyperventilation may occur and be deleterious.

Some patients, more often neonates (discussed later), receive ventilation via high-frequency oscillators or jet ventilators. Some teams have the ability to transport on portable jet ventilators, and in this case, the change should be made directly, again checking the adequacy of ventilation and oxygenation after the switch. If the patient must be transitioned from high-frequency to conventional ventilation for transport, the calculations of approximate mean airway pressures, inspiratory times, inspiratory:expiratory (I:E) ratios, and expected rates should be carefully done prior to the change. This also applies to the switching of patients from a high-frequency oscillator to a jet ventilator for transport.

If the patient is not being mechanically ventilated, concern must be paid to correct positioning of the patient at all times. Sometimes the patient can actively participate in this activity, but in most instances the ICU patient will require continuous efforts by the transport team to ensure adequate oxygenation. The most common modes of oxygen delivery to the nonintubated ICU patient are via nasal cannula or through a nonrebreather mask system, sometimes in conjunction with an oro- or nasopharyngeal airway. Appropriate hand-off of care should include the current oxygen requirement of a nonintubated patient. However, oxygen needs typically increase during transport, and oxygen delivery should be adjusted as needed.

Nonmechanically ventilated patients present a complex picture for transport. Care must be taken to fully evaluate the individual patient’s airway, underlying diagnoses, current illness, and any prior diagnoses/conditions that would complicate any endotracheal intubation required during transport, such as morbid obesity or any cervical spine mobility issues. A patient’s level of consciousness should be fully assessed prior to the initiation of transport; patients with decreased levels of consciousness or disorientation may not be safe for transport without a stable artificial airway.

Blood Pressure Management in Transporting the ICU Patient

When patients are being picked up for transport at an outside facility by the accepting hospital’s team, all infusions are usually redone (recalculated, remixed, and placed on the transport team’s equipment) and set to run at the dose given by the primary care team. This process ensures consistency with the receiving institution’s concentrations and pumps, and it decreases the risk of medication errors by eliminating the need to employ unfamiliar rates or the inability to run certain setups on other pumps. Acute blood pressure shifts are frequent when transiently interrupting pressor infusions. It is essential to individually switch the infusions over to the transport set gradually and allow enough time to resolve hemodynamic changes, establish possibly new baselines, and adjust infusion rates.

As mentioned previously, switching pressor drips can be challenging during the initiation of transport from a referring hospital. During in-hospital transport for procedures, testing, or transfers, however, the currently active infusions can usually be maintained. This avoids many blood pressure swings seen when switching infusions. Most likely the equipment, concentrations, and rates are either identical or compatible, and they are institutionally regulated. Frequently, the patient is returning to the previous nurse and bed location after a procedure or test. When transporting a patient from one’s home institution to another facility, ICU team members should take great care to have an adequate supply of medications and infusions for the duration of transport while factoring in possible and unforeseen delays.

Hemodynamic stability may be difficult to maintain on transport, as the stress of transport on the ICU patient may provoke extreme fluctuations in blood pressure. This is especially important to remember when using other commonly used medications on transport, such as sedatives, opioids, and neuromuscular blockers, as sedatives and opioids tend to decrease systemic blood pressure.

Special Cases in ICU Transports