- Email: [email protected]
Respiratory Therapy Approaches to the Patient with Sepsis
Abstract: Early, goal-directed therapies, including effective oxygen delivery, are essential in providing good outcomes for the patient with sepsis. Understanding sepsis and the mechanisms that drive oxygen delivery is important in determining appropriate therapies to support oxygenation. Noninvasive modes of oxygen delivery, including noninvasive positive pressure ventilation, should be used early and escalated as determined by the patient’s clinical signs and symptoms.
Keywords: hypoxemic respiratory failure; oxygen delivery; oxygen consumption; high-flow nasal cannula; nasal CPAP
Respiratory Therapy Approaches to the Patient with Sepsis Kellianne Fleming, BA, RRT
O Respiratory Care, Clinical Manager, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL. Reprint requests and correspondence: Kellianne Fleming, BA, RRT, Respiratory Care, Clinical Manager, Ann & Robert H. Lurie Children’s Hospital of Chicago, 225 E. Chicago Ave, Chicago, IL 60611-2605. [email protected] 1522-8401 © 2014 Published by Elsevier Inc.
ne of the greatest challenges in treating sepsis in children, regardless of age, is the consistent, effective delivery of oxygen. Maintaining sufficient oxygen delivery to the tissues along with maintaining adequate perfusion are the key elements of sepsis management. Oxygen delivery, as defined by the following formula, encompasses the complete cardiopulmonary system, with each segment vulnerable to compromise in the face of sepsis: 1 Oxygen delivery = cardiac output (heart rate × stroke volume) × oxygen content (hemoglobin [Hgb] level × 1.34 × arterial oxygen saturation) + (PaO2 × 0.003). Because of the many barriers to tissue oxygenation that the septic patient encounters, the respiratory therapist must be diligent in their task of providing optimal oxygen delivery, while closely monitoring patient response to such therapies. In addition to the delivery of oxygen, therapists must play close attention to laboratory values, specifically PaO2, mixed venous oxygen saturation (SvO2) and Hgb level, and the impact those values have on tissue oxygenation. High oxygen delivery is a driver to better patient outcomes in certain populations; however, it is important to keep in mind that oxygen delivery does not guarantee oxygen uptake. Using the oxygen delivery formula as our reference, this review will consider the variety of oxygen delivery systems, oxygenation markers, and adjunct therapies to optimize efforts to provide adequate tissue oxygenation, thereby decreasing the opportunity for end-organ dysfunction.
RESPIRATORY THERAPY APPROACHES TO THE PATIENT WITH SEPSIS / FLEMING • VOL. 15, NO. 2 123
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RESPIRATORY ASSESSMENT OF THE SEPTIC CHILD Early recognition of sepsis in conjunction with appropriate interventions provides first responders with the unique opportunity to change the course of a septic child. In the pediatric patient, some of the first signs of sepsis are tachypnea, tachycardia, and fever. 1,2 It is expected that the pediatric patient will be tachypneic in the early stages of sepsis, increasing their minute ventilation as a compensatory mechanism for their metabolic acidosis. 2 Early goaldirected therapy (EGDT), as recommended by the Surviving Sepsis Campaign suggest the immediate use of 1.0 fraction of inspired oxygen (FiO2) via nasal cannula or facemask. 1,3 Concurrently, the patient should be assessed for airway patency, appropriate mental status, the ability to protect their airway, work of breathing, and gas exchange. 1 Oxygen saturations should be watched closely, and preferably, an arterial gas should be obtained. Results of the blood gas should be interpreted to determine the acid-base status, ventilation status, and evidence of tissue hypoxemia. These results will assist the respiratory therapist in determining the best options for oxygen delivery. Oxygen therapy is the first line of treatment for acute hypoxemic respiratory failure with the ultimate goal of adequate tissue oxygenation and perfusion. In response to the patient’s work of breathing and level of hypoxemia, therapeutic respiratory support may be increased to include the use of noninvasive positive pressure ventilation as well as endotracheal intubation and mechanical ventilation.
meet the patient’s peak inspiratory flow demands, which will present the opportunity for the patient to entrain ambient air. High-flow nasal cannula (HFNC) is an appropriate first line of support for hypoxemic respiratory failure. Hypoxemic respiratory failure is defined a PaO2 less than or equal to 60 in the absence of hypercarbia. 4 Recommended treatment for hypoxemic respiratory failure is the administration of supplemental oxygen with the goal to achieve an arterial oxygen saturation of 94% with an FiO2 of less than 0.5. 4 High-flow nasal cannula is often well tolerated due to the fact that it is able to deliver heated and humidified gas. More importantly, high flow diminishes air dilution, delivering a consistent FiO2 and decreases work of breathing by consistently meeting or exceeding the patient’s flow demands. 5,6 Highflow nasal cannula reduces symptoms of respiratory distress and improves oxygenation by providing positive pressure and the opportunity for alveolar recruitment. Recent studies suggest that the high flow can generate mean airway pressures between 2.7 and 7.4 cm H2O depending on the flow rates. 7 Eight liters per minute has been determined to deliver approximately 5 cm H2O of continuous positive airway pressure (CPAP). 5 The high flows delivered to the nasopharynx promote a flushing out
OXYGEN DELIVERY Oxygen should be delivered as an empirical therapy to the patient suspected of having sepsis. At minimum, a 2 L/min nasal cannula should be applied, after which the patient is assessed. 2 If it is determined that the patient requires more oxygen to maintain oxygen saturations, a nonrebreather mask at 15 L/min can be used. The patient supported with a nonrebreather, who continues to exhibit an increased work of breathing and suboptimal saturations, requires an increase in support. Oxygen delivery devices vary, each with benefits and limitations. The optimal oxygen delivery device will be the one that the patient can tolerate, yet also meeting the patient’s flow demands and delivering a consistent FiO2. Facemask and standard nasal cannulas may not have the capacity to consistently meet the FiO2 requirement due to the inability to
Circuit
Pop-Off Valve
Water Chamber
Figure 1. Fisher & Paykel infant respiratory care system (infant continuous flow circuit).
RESPIRATORY THERAPY APPROACHES TO THE PATIENT WITH SEPSIS / FLEMING • VOL. 15, NO. 2 125
Figure 2. Fisher & Paykel infant oxygen therapy nasal cannula.
of CO2 therefore reducing dead space and eliminating the opportunity to rebreathe CO2. 5,6 In addition, the high flows improve alveolar ventilation and increase the patient’s functional residual capacity. Figure 1 is an example of the Fisher & Paykel (Auckland, New Zealand) high-flow system. It is important to remember that the Fisher & Paykel system uses a “pop-off” valve as a safety mechanism, only allowing flows up to 8 L/min using the infant and pediatric size cannula (Figure 2). The Opti-flow (Auckland, New Zealand) cannula, for adults, can deliver at least 40 L/min. When sizing a patient for the appropriate size cannula, the cannula should not occlude more than 75% of the nares. Cannulae come in sizes ranging from neonatal to adult. The Precision Flow system, by Vapotherm, Exeter, NH (Figure 3), consists of 2 cartridges, a low-flow cartridge to accommodate flows up to 8 L/min and a high-flow cartridge for pediatric and adult patients that can deliver up to 40 L/min. Both cartridges can deliver FiO2 up to 1.0. Flow should be titrated based on the patient’s clinical response to therapy. A small prospective study investigating patient tolerance and clinical response to HFNC delivery enrolled 46 patients ranging in age from newborn to the age of 12 years. Infants were placed on HFNC using Vapotherm with flows ranging from 8 to 12 L/min and
Liters/min
20 to 30 L/min for children. The results of the study showed that the patients were able to tolerate the high flow, and oxygen saturations increased 60 to 90 minutes following the initiation of HFNC. 8 In a similar study with adults, there were reports of patients feeling chest discomfort at the initiation of high flow that ultimately dissipated. 6 In such circumstances, it would be appropriate to reduce flow and increase it over time. 9 Noninvasive ventilation should be titrated to meet goal-directed therapy of adequate oxygen saturations, decreased work of breathing, and patient tolerance. 10 If HFNC is unable to provide necessary support to decrease the patient’s work of breathing, other alternatives should be used. Continuous positive airway pressure is delivered through nasal mask or prongs. Unlike when sizing a cannula for HFNC, it is important to use the largest size prong that can comfortably occlude the nare without causing undue pressure. 11 Continuous positive airway pressure provides a guaranteed, measured, continual positive end-expiratory pressure above what may be attainable through high flow. 14 Unlike high flow, where the flow is constant and the pressure is variable, CPAP has a varying flow to support the prescribed CPAP level, and pressure can be quantified. 15 It is recommended to initiate CPAP at levels of 4 to 6 cm H2O. Figure 4 demonstrates an example of the Airlife (Carefusion, San Diego, CA) Nasal CPAP system commonly used in the neonatal and infant population. Continuous positive airway pressure can also be delivered to the older child and adult population through a nasal or full face mask using any one of the noninvasive positive pressure ventilator devices. Ideally, CPAP will be able to provide sufficient positive end-expiratory pressure to recruit alveoli and promote better gas exchange. As with all therapies, CPAP level should be titrated based on clinical signs and symptoms.
FiO2
Inter-changeable low-flow and highflow cartridge.
Temperature
Figure 3. Vapotherm precision oxygen flow system.
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Set CPAP
FiO2
Variable Flow
Figure 4. Infant nasal CPAP system.
OXYGEN CONSUMPTION Oxygen consumption is evaluated by the results of the central venous saturation or SvO2. The preferred venous gas would be obtained from a central venous line; however, if unable, a mixed venous saturation is acceptable. In the “well” patient, it is expected that the venous saturation of the blood will be near 75 %. Healthy tissue will extract approximately 25% of the oxygen delivered, whereas the remaining 75% will be returned to the lungs. In the septic patient, with high metabolic demands, it is expected that the SvO2 will be less than 75 % due to the increased need for oxygen by the tissues. The severity of sepsis will be evident by the SvO2 and blood lactate levels. Much of the increased metabolic demand could be the result of the patient’s compensatory mechanism of increased work of breathing. Early and aggressive respiratory support can help alleviate oxygen demands. Early goal-directed therapy has shown better patient outcomes and less end-organ dysfunction in those children who were able to maintain a central venous saturation of at least 70 mm Hg or an ScvO2 of at least 65 %. The respiratory therapist should carefully monitor patient response to the provided respiratory support. If the patient cannot maintain adequate tissue oxygenation within these ranges, an escalation in support should be considered. 1,3
CARDIAC OUTPUT AND OXYGEN CONTENT As evident in the oxygen delivery calculation, cardiac output and oxygen content need to be optimized to ensure sufficient oxygen delivery. Close monitoring and prompt treatment of Hgb level less than 7 g/dL is essential to good patient outcomes. Blood products should be used to attain
the EGDT target Hgb level of 7 to 9 g/dL in the patient who is not experiencing tissue hypoperfusion, as recommended by the Surviving Sepsis Campaign. 1,3 However, there is evidence to suggest that an Hgb level of 10 g/dL is linked to improved outcomes in adult patients with sepsis. 3 Without an adequate Hgb level, good tissue oxygen delivery is not a possibility. Diminished cardiac output can often be managed in part with aggressive fluid resuscitation if the patient is hypovolemic. Although necessary for hemodynamic support, fluid resuscitation may impact the end goal of oxygen delivery and may necessitate an increase in support. The systemic inflammatory response syndrome with its associated capillary leak and myocardial compromise can result in pulmonary edema and compromised gas exchange with the potential to develop into acute respiratory distress syndrome. This evolution toward profound ventilation-perfusion mismatch can present challenges to the respiratory therapist and the critical care team, and often, intubation and mechanical ventilation is required for maximal support.
SUMMARY The respiratory therapist’s approach to the septic patient should be one of urgency in regards to the expeditious delivery of supplemental oxygen. Considering the oxygen delivery formula, the therapist should understand the barriers to oxygen delivery that are characteristic of sepsis, and have a plan to treat hypoxemic respiratory failure. Using the clinical signs and laboratory values available, the respiratory therapist should be able to assess the severity of the patient’s hypoxemia and address it with the next level of respiratory support. As substantiated by the Surviving
RESPIRATORY THERAPY APPROACHES TO THE PATIENT WITH SEPSIS / FLEMING • VOL. 15, NO. 2 127
Sepsis Campaign, early, proactive, and goal-directed respiratory therapies promote excellent patient care and outcomes.
REFERENCES 1. El-wiher N, Cornell TT, Kissoon N, et al. Management and treatment guidelines for sepsis in pediatric patients. Open Inflamm J 2011;4:101–9. 2. Biban P, Gaffuri M, Spaggiari S, et al. Early recognition and management of septic shock in children. Pediatr Rep 2012;4:e13. 3. Dellinger RP, Levy MM, Rhodes A, et al. Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2012. Crit Care Med J 2013;41:581–637. 4. Hajaf-Zadeh A, Leclerc F. Noninvasive positive pressure ventilation for acute respiratory failure in children: a concise review. Ann Intensive Care 2011;1:15. 5. Kubicka ZJ, Limauro J, Darnall RA. Heated, humidified high-flow nasal cannula therapy: yet another way to deliver continuous positive airway pressure? Pediatrics 2010;121:82–8.
6. Roca O, Riera J, Torres F, et al. High-flow oxygen therapy in acute respiratory failure. Respir Care 2010;55:408–12. 7. El-Khatib M. High-flow nasal cannula oxygen therapy during hypoxemic respiratory failure. Respir Care 2012;57:1696–8. 8. Ward JJ. High-flow oxygen administration by nasal cannula for adult and perinatal patients. Respir Care 2013;58:98–122. 9. Agarwal R, Handa A, Aggarwal AN, et al. Outcomes of noninvasive ventilation in acute hypoxemic respiratory failure in a respiratory intensive care unit in North India. Respir Care 2009;54:1679–87. 10. Inwald DP, Tasker RC, Peters MJ, et al. Emergency management of children with severe sepsis in the United Kingdom: the results of the Paediatric Intensive Care Society sepsis audit. Arch Dis Child 2009;94:348–53. 11. Ricard J. High flow nasal oxygen in acute respiratory failure. Minerva Anestesiol 2012;78:836–41. 12. MacIntyre NR, Nava S, DiBlasi RM, et al. Invasive mechanical ventilation, noninvasive ventilation, pediatric mechanical ventilation, aerosol therapy. Respir Care 2011;56:667–79. 13. Sivieri EM, Gerdes JS, Abbasi S. Effect of HFNC flow rate, cannula size, and nares diameter on generated airway pressures: an in vitro study. Pediatr Pulmonol 2012;48:506–14.
Keywords: hypoxemic respiratory failure; oxygen delivery; oxygen consumption; high-flow nasal cannula; nasal CPAP
Respiratory Therapy Approaches to the Patient with Sepsis Kellianne Fleming, BA, RRT
O Respiratory Care, Clinical Manager, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL. Reprint requests and correspondence: Kellianne Fleming, BA, RRT, Respiratory Care, Clinical Manager, Ann & Robert H. Lurie Children’s Hospital of Chicago, 225 E. Chicago Ave, Chicago, IL 60611-2605. [email protected] 1522-8401 © 2014 Published by Elsevier Inc.
ne of the greatest challenges in treating sepsis in children, regardless of age, is the consistent, effective delivery of oxygen. Maintaining sufficient oxygen delivery to the tissues along with maintaining adequate perfusion are the key elements of sepsis management. Oxygen delivery, as defined by the following formula, encompasses the complete cardiopulmonary system, with each segment vulnerable to compromise in the face of sepsis: 1 Oxygen delivery = cardiac output (heart rate × stroke volume) × oxygen content (hemoglobin [Hgb] level × 1.34 × arterial oxygen saturation) + (PaO2 × 0.003). Because of the many barriers to tissue oxygenation that the septic patient encounters, the respiratory therapist must be diligent in their task of providing optimal oxygen delivery, while closely monitoring patient response to such therapies. In addition to the delivery of oxygen, therapists must play close attention to laboratory values, specifically PaO2, mixed venous oxygen saturation (SvO2) and Hgb level, and the impact those values have on tissue oxygenation. High oxygen delivery is a driver to better patient outcomes in certain populations; however, it is important to keep in mind that oxygen delivery does not guarantee oxygen uptake. Using the oxygen delivery formula as our reference, this review will consider the variety of oxygen delivery systems, oxygenation markers, and adjunct therapies to optimize efforts to provide adequate tissue oxygenation, thereby decreasing the opportunity for end-organ dysfunction.
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RESPIRATORY ASSESSMENT OF THE SEPTIC CHILD Early recognition of sepsis in conjunction with appropriate interventions provides first responders with the unique opportunity to change the course of a septic child. In the pediatric patient, some of the first signs of sepsis are tachypnea, tachycardia, and fever. 1,2 It is expected that the pediatric patient will be tachypneic in the early stages of sepsis, increasing their minute ventilation as a compensatory mechanism for their metabolic acidosis. 2 Early goaldirected therapy (EGDT), as recommended by the Surviving Sepsis Campaign suggest the immediate use of 1.0 fraction of inspired oxygen (FiO2) via nasal cannula or facemask. 1,3 Concurrently, the patient should be assessed for airway patency, appropriate mental status, the ability to protect their airway, work of breathing, and gas exchange. 1 Oxygen saturations should be watched closely, and preferably, an arterial gas should be obtained. Results of the blood gas should be interpreted to determine the acid-base status, ventilation status, and evidence of tissue hypoxemia. These results will assist the respiratory therapist in determining the best options for oxygen delivery. Oxygen therapy is the first line of treatment for acute hypoxemic respiratory failure with the ultimate goal of adequate tissue oxygenation and perfusion. In response to the patient’s work of breathing and level of hypoxemia, therapeutic respiratory support may be increased to include the use of noninvasive positive pressure ventilation as well as endotracheal intubation and mechanical ventilation.
meet the patient’s peak inspiratory flow demands, which will present the opportunity for the patient to entrain ambient air. High-flow nasal cannula (HFNC) is an appropriate first line of support for hypoxemic respiratory failure. Hypoxemic respiratory failure is defined a PaO2 less than or equal to 60 in the absence of hypercarbia. 4 Recommended treatment for hypoxemic respiratory failure is the administration of supplemental oxygen with the goal to achieve an arterial oxygen saturation of 94% with an FiO2 of less than 0.5. 4 High-flow nasal cannula is often well tolerated due to the fact that it is able to deliver heated and humidified gas. More importantly, high flow diminishes air dilution, delivering a consistent FiO2 and decreases work of breathing by consistently meeting or exceeding the patient’s flow demands. 5,6 Highflow nasal cannula reduces symptoms of respiratory distress and improves oxygenation by providing positive pressure and the opportunity for alveolar recruitment. Recent studies suggest that the high flow can generate mean airway pressures between 2.7 and 7.4 cm H2O depending on the flow rates. 7 Eight liters per minute has been determined to deliver approximately 5 cm H2O of continuous positive airway pressure (CPAP). 5 The high flows delivered to the nasopharynx promote a flushing out
OXYGEN DELIVERY Oxygen should be delivered as an empirical therapy to the patient suspected of having sepsis. At minimum, a 2 L/min nasal cannula should be applied, after which the patient is assessed. 2 If it is determined that the patient requires more oxygen to maintain oxygen saturations, a nonrebreather mask at 15 L/min can be used. The patient supported with a nonrebreather, who continues to exhibit an increased work of breathing and suboptimal saturations, requires an increase in support. Oxygen delivery devices vary, each with benefits and limitations. The optimal oxygen delivery device will be the one that the patient can tolerate, yet also meeting the patient’s flow demands and delivering a consistent FiO2. Facemask and standard nasal cannulas may not have the capacity to consistently meet the FiO2 requirement due to the inability to
Circuit
Pop-Off Valve
Water Chamber
Figure 1. Fisher & Paykel infant respiratory care system (infant continuous flow circuit).
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Figure 2. Fisher & Paykel infant oxygen therapy nasal cannula.
of CO2 therefore reducing dead space and eliminating the opportunity to rebreathe CO2. 5,6 In addition, the high flows improve alveolar ventilation and increase the patient’s functional residual capacity. Figure 1 is an example of the Fisher & Paykel (Auckland, New Zealand) high-flow system. It is important to remember that the Fisher & Paykel system uses a “pop-off” valve as a safety mechanism, only allowing flows up to 8 L/min using the infant and pediatric size cannula (Figure 2). The Opti-flow (Auckland, New Zealand) cannula, for adults, can deliver at least 40 L/min. When sizing a patient for the appropriate size cannula, the cannula should not occlude more than 75% of the nares. Cannulae come in sizes ranging from neonatal to adult. The Precision Flow system, by Vapotherm, Exeter, NH (Figure 3), consists of 2 cartridges, a low-flow cartridge to accommodate flows up to 8 L/min and a high-flow cartridge for pediatric and adult patients that can deliver up to 40 L/min. Both cartridges can deliver FiO2 up to 1.0. Flow should be titrated based on the patient’s clinical response to therapy. A small prospective study investigating patient tolerance and clinical response to HFNC delivery enrolled 46 patients ranging in age from newborn to the age of 12 years. Infants were placed on HFNC using Vapotherm with flows ranging from 8 to 12 L/min and
Liters/min
20 to 30 L/min for children. The results of the study showed that the patients were able to tolerate the high flow, and oxygen saturations increased 60 to 90 minutes following the initiation of HFNC. 8 In a similar study with adults, there were reports of patients feeling chest discomfort at the initiation of high flow that ultimately dissipated. 6 In such circumstances, it would be appropriate to reduce flow and increase it over time. 9 Noninvasive ventilation should be titrated to meet goal-directed therapy of adequate oxygen saturations, decreased work of breathing, and patient tolerance. 10 If HFNC is unable to provide necessary support to decrease the patient’s work of breathing, other alternatives should be used. Continuous positive airway pressure is delivered through nasal mask or prongs. Unlike when sizing a cannula for HFNC, it is important to use the largest size prong that can comfortably occlude the nare without causing undue pressure. 11 Continuous positive airway pressure provides a guaranteed, measured, continual positive end-expiratory pressure above what may be attainable through high flow. 14 Unlike high flow, where the flow is constant and the pressure is variable, CPAP has a varying flow to support the prescribed CPAP level, and pressure can be quantified. 15 It is recommended to initiate CPAP at levels of 4 to 6 cm H2O. Figure 4 demonstrates an example of the Airlife (Carefusion, San Diego, CA) Nasal CPAP system commonly used in the neonatal and infant population. Continuous positive airway pressure can also be delivered to the older child and adult population through a nasal or full face mask using any one of the noninvasive positive pressure ventilator devices. Ideally, CPAP will be able to provide sufficient positive end-expiratory pressure to recruit alveoli and promote better gas exchange. As with all therapies, CPAP level should be titrated based on clinical signs and symptoms.
FiO2
Inter-changeable low-flow and highflow cartridge.
Temperature
Figure 3. Vapotherm precision oxygen flow system.
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Set CPAP
FiO2
Variable Flow
Figure 4. Infant nasal CPAP system.
OXYGEN CONSUMPTION Oxygen consumption is evaluated by the results of the central venous saturation or SvO2. The preferred venous gas would be obtained from a central venous line; however, if unable, a mixed venous saturation is acceptable. In the “well” patient, it is expected that the venous saturation of the blood will be near 75 %. Healthy tissue will extract approximately 25% of the oxygen delivered, whereas the remaining 75% will be returned to the lungs. In the septic patient, with high metabolic demands, it is expected that the SvO2 will be less than 75 % due to the increased need for oxygen by the tissues. The severity of sepsis will be evident by the SvO2 and blood lactate levels. Much of the increased metabolic demand could be the result of the patient’s compensatory mechanism of increased work of breathing. Early and aggressive respiratory support can help alleviate oxygen demands. Early goal-directed therapy has shown better patient outcomes and less end-organ dysfunction in those children who were able to maintain a central venous saturation of at least 70 mm Hg or an ScvO2 of at least 65 %. The respiratory therapist should carefully monitor patient response to the provided respiratory support. If the patient cannot maintain adequate tissue oxygenation within these ranges, an escalation in support should be considered. 1,3
CARDIAC OUTPUT AND OXYGEN CONTENT As evident in the oxygen delivery calculation, cardiac output and oxygen content need to be optimized to ensure sufficient oxygen delivery. Close monitoring and prompt treatment of Hgb level less than 7 g/dL is essential to good patient outcomes. Blood products should be used to attain
the EGDT target Hgb level of 7 to 9 g/dL in the patient who is not experiencing tissue hypoperfusion, as recommended by the Surviving Sepsis Campaign. 1,3 However, there is evidence to suggest that an Hgb level of 10 g/dL is linked to improved outcomes in adult patients with sepsis. 3 Without an adequate Hgb level, good tissue oxygen delivery is not a possibility. Diminished cardiac output can often be managed in part with aggressive fluid resuscitation if the patient is hypovolemic. Although necessary for hemodynamic support, fluid resuscitation may impact the end goal of oxygen delivery and may necessitate an increase in support. The systemic inflammatory response syndrome with its associated capillary leak and myocardial compromise can result in pulmonary edema and compromised gas exchange with the potential to develop into acute respiratory distress syndrome. This evolution toward profound ventilation-perfusion mismatch can present challenges to the respiratory therapist and the critical care team, and often, intubation and mechanical ventilation is required for maximal support.
SUMMARY The respiratory therapist’s approach to the septic patient should be one of urgency in regards to the expeditious delivery of supplemental oxygen. Considering the oxygen delivery formula, the therapist should understand the barriers to oxygen delivery that are characteristic of sepsis, and have a plan to treat hypoxemic respiratory failure. Using the clinical signs and laboratory values available, the respiratory therapist should be able to assess the severity of the patient’s hypoxemia and address it with the next level of respiratory support. As substantiated by the Surviving
RESPIRATORY THERAPY APPROACHES TO THE PATIENT WITH SEPSIS / FLEMING • VOL. 15, NO. 2 127
Sepsis Campaign, early, proactive, and goal-directed respiratory therapies promote excellent patient care and outcomes.
REFERENCES 1. El-wiher N, Cornell TT, Kissoon N, et al. Management and treatment guidelines for sepsis in pediatric patients. Open Inflamm J 2011;4:101–9. 2. Biban P, Gaffuri M, Spaggiari S, et al. Early recognition and management of septic shock in children. Pediatr Rep 2012;4:e13. 3. Dellinger RP, Levy MM, Rhodes A, et al. Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2012. Crit Care Med J 2013;41:581–637. 4. Hajaf-Zadeh A, Leclerc F. Noninvasive positive pressure ventilation for acute respiratory failure in children: a concise review. Ann Intensive Care 2011;1:15. 5. Kubicka ZJ, Limauro J, Darnall RA. Heated, humidified high-flow nasal cannula therapy: yet another way to deliver continuous positive airway pressure? Pediatrics 2010;121:82–8.
6. Roca O, Riera J, Torres F, et al. High-flow oxygen therapy in acute respiratory failure. Respir Care 2010;55:408–12. 7. El-Khatib M. High-flow nasal cannula oxygen therapy during hypoxemic respiratory failure. Respir Care 2012;57:1696–8. 8. Ward JJ. High-flow oxygen administration by nasal cannula for adult and perinatal patients. Respir Care 2013;58:98–122. 9. Agarwal R, Handa A, Aggarwal AN, et al. Outcomes of noninvasive ventilation in acute hypoxemic respiratory failure in a respiratory intensive care unit in North India. Respir Care 2009;54:1679–87. 10. Inwald DP, Tasker RC, Peters MJ, et al. Emergency management of children with severe sepsis in the United Kingdom: the results of the Paediatric Intensive Care Society sepsis audit. Arch Dis Child 2009;94:348–53. 11. Ricard J. High flow nasal oxygen in acute respiratory failure. Minerva Anestesiol 2012;78:836–41. 12. MacIntyre NR, Nava S, DiBlasi RM, et al. Invasive mechanical ventilation, noninvasive ventilation, pediatric mechanical ventilation, aerosol therapy. Respir Care 2011;56:667–79. 13. Sivieri EM, Gerdes JS, Abbasi S. Effect of HFNC flow rate, cannula size, and nares diameter on generated airway pressures: an in vitro study. Pediatr Pulmonol 2012;48:506–14.