Conclusions



MANAGEMENT OF INTUBATED AND VENTILATED PATIENTS DIAGNOSED WITH ARDS/ALI

Background

• The definition used for acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) in this clinical algorithm is based on the American European Consensus Conference on ARDS (Ball 1999). The concern related to PaO2:FiO2 ratio documented recently by Karbing et al (2007) is noted.

• There seems to be a difference in the respiratory dynamics in ARDS developed from pulmonary and extra pulmonary origin (Tagrul et al 2003). Future studies should evaluate the effect of techniques in these two patient groups separately.

Review question 1: What is the optimal position to optimize oxygenation in intubated and ventilated patients presenting with ARDS / ALI?

Following a systematic search of the literature; critical appraisal of identified studies; the following conclusions were reached:

SEARCH RESULTS

• One meta-analysis (Alsaghir et al 2008) and 2 clinical guidelines (Ball 2001; Rowe 2004) were identified on prone positioning (refer to table 1 for summary of meta-analysis.)

• The clinical guideline developed by (Ball 2001) followed an inclusive approach in the development. The formulation process moved from a topic of discussion for implementation at a specific unit; to discussions with interdisciplinary team members at a regional nursing forum; NHS trust meeting; and units outside the trust.

• The clinical guideline developed by Rowe (2004) was developed for use in an intensive care unit that periodically used prone positioning maneuver as a last option to improve oxygenation in patients suffering from ARDS. It is hypothesized by the author that these evidence based guidelines could facilitate the use of prone positioning.

Table 1 Summary of meta- analysis

|Review |AMSTAR |Studies |Population |Intervention and |Outcomes measured |Conclusion |

| |Score |included | |comparison | | |

SUMMARY OF EVIDENCE

• Prone positioning significantly improves oxygenation in patients presenting with ARDS (Alsaghir et al 2008) although it does not not positively impact survival.

• PP must be instituted as soon as possible and in consultation with multidisciplinary team (Ball et al 2001; Alsaghir et al 2008)

• It is a safe procedure if monitored closely, with the greatest adverse events (eg disconnection from ventilator; dislodging of lines) taking place during the process of proning (Alsaghir et al 2008).

Expert opinion: Practical points

• The provision of specific guidelines for the application of the positioning could possible result in more compliance with the procedure (Ball et al 2001; Alsaghir et al 2008; Guerin et al 2004). Even though this is an observation it is mentioned by all three authors and could thus be regarded as expert opinion.

• If there is no improvement in oxygenation after 6 hours patients can be regarded as non responders, but in responders the continuation of prone position is important up to 20 hours per day for at least 7 days (Alsaghir et al 2008).

• Great care must be taken with pressure relief in the prone position (Alsaghir et al 2008; Ball 2001) Expert opinion

QUALITY OF STUDIES

• The meta-analysis (Alsaghir et al 2008) was well conducted and scored 8/11 on AMSTAR. Conflicts of interest were not stated and a list of excluded studies was not provided. The authors mention that due to small number of studies publication bias was not assessed.

• The clinical guideline developed by (Ball 2001) scored highest in the scope and purpose domain (88%) and moderately in stakeholder involvement domain (66%). However the most important domain rigor of development scored 33% (refer to table 2)

• The clinical guideline (Rowe 2004) did not reach 50 % in any of the domains analyzed (refer to table 2).

• Based on guidelines for the development of the algorithm in this study, both these two guidelines will be incorporated as Expert opinion

•

Table 2: Summary of AGREE domain scores (scores are percentages)

|Clinical |Subject |Scope And Purpose |Stakeholder |Rigor Of Development |Clarity And |Applicability |Editorial |

|guideline | | |Involvement | |Presentation | |Independence |

|Rowe 2004 |Development of clinical |38% |0% |5% |33% |0% |0% |

| |guidelines for prone | | | | | | |

| |positioning in critically | | | | | | |

| |ill adults | | | | | | |

Review question 2: Which CPT techniques can improve the oxygenation in intubated and ventilated patients presenting with ARDS / ALI?

Following a systematic search of the literature; critical appraisal of identified studies; the following conclusions were reached:

SEARCH RESULTS

• Three experimental studies were identified that evaluated the effect of CPT in acute lung injury patients (Barker et al 2002; Dyhr et al 2003; Davis et al 2001)

• Two examined the effect of MHI on lung recruitment (Barker et al 2002; Dyer et al 2003) while a third study evaluated the effect of turning and percussion and PD on hemodynamics and sputum volume (Davis et al 2001).

Table 3 Summary of experimental studies

|Studies |Internal |Sample size |Population |Intervention and comparison |Study structure |Outcome measured |

| |validity | | | | | |

| |(Pedro | | | | | |

| |Score) | | | | | |

|Dyer et al 2003; |5 |8 |Intubated and ventilated |Suction compared to suction and |Crossover RCT |Pa O2 |

| | | |diagnosed ARDS |lung recruitment maneuver | | |

|Davis et al 2001 |5 |19 |Intubated and ventilated |Each stage was for a 6 hour period. |Crossover RCT |Sputum volume |

| | | |diagnosed ARDS |2 hourly turn by nursing staff | | |

| | | | |compared to two hourly turn and 15 | | |

| | | | |min percussion compared to | | |

| | | | |continuous lateral rotation in | | |

| | | | |specialized bed compared to | | |

| | | | |continuous lateral rotation in | | |

| | | | |specialized bed with mechanical | | |

| | | | |percussion every 2 hours. | | |

SUMMARY OF EVIDENCE

• Suction must only be completed when clinically indicated - due to derecruitment that takes place when suctioning is performed (Dyhr et al 2003; Barker et al 2002)

• A lung recruitment maneuver could be instituted immediately following suction (Dyhr et al 2003)

• No harm was reported in the 19 patients studied in terms of fluctuation in BP or arythmias (Dyhr et al 2003)

• Could possible use in line suction but has been shown to be less effective in clearing secretions (Dyhr et al 2003)

• The routine use of side lying and MHI is not recommended for patients with ALI/ARDS (Barker et al 2002)

QUALITY OF STUDIES IDENTIFIED

• Two studies observed decruitment as result of disconnection from ventilator (Barker et al 2002 and Dyhr et al 2003) refer to table 2 and 3.

• Dyhr et al (2003) reported an immediate return to baseline following a recruitment maneuver immediately after suctioning. The quality of this study is downgraded to moderate quality evidence because of imprecision of data. (refer to table 3)

• Davis et al (2001) reported that continuous lateral rotation in specialized bed did increase the volume of sputum cleared. The quality of the study is downgraded to very low due to methodological quality; directness and precision. As these beds are not routinely used in units this study could be used as basis for better quality studies rather than the incorporation of this evidence into the management algorithm.

Table 2 Factors considered in determining the quality of the evidence for experimental studies

|Experimental |Risk of bias | |Heterogeneity | |

|Studies | |Directness of evidence | |Precision |

| |Concealed allocation |LTFO |ITT |Intervention investigated |

| | |Lost to follow up | | |

|Study design |Washout period |Sample selected |Intervention investigated |Sample investigated |Publication Bias |Data |Sample | |Dyer et al 2003; |Yes

appropriate |Yes appropriate (97% of baseline) |yes appropriate |Yes |Yes |NA |Unable to calculate treatment effect (mean difference of change from baseline) |Yes (80% power | |Davis et al 2001 |Yes (Outcomes measured could be affected by other management strategies within 1 24 period) |Yes (No washout period was provided. Continuous in 6 hourly phases through a 24 hour period) |Yes (No APACHE) |Beds are costly and not routinely available |ARDS |NA |Unable to calculate treatment effect (mean difference of change from baseline) |No | |

-----------------------

RECOMMENDATIONS

Recommendation 1 Post your comments on the website

• Patients diagnosed with ARDS/ALI might be positioned in prone position as soon as possible following diagnosis to improve oxygenation for a period of at least 6 hours and a maximum of 20 hours per day.

Weak recommendation: The meta-analysis (Alsighir et al 2008) based on the results of 5 high quality RCT’s concluded that prone positioning significantly improves oxygenation. No effect was established on survival; time on the ventilator or incidence of ventilator associated pneumonia. Whether this improved oxygenation could affect long term outcome including quality of life is not clear, and concerns have been raised to the high burden of implementation based on

moderate quality evidence: A well conducted meta analyses based on five high quality RCT’s. The evidence is downgraded due to imprecision of data (wide CI)

Expert opinion

• Compliance with proning procedure is expected to increase with the implementation of a procedural protocol (Ball et al 2001; Alsaghir et al 2008; Rowe 2004)

Recommendation 2

• The routine suctioning of patients diagnosed with ARDS/ALI is not recommended and patients might only be suctioned when clinically indicated. VHI (two hyperinflations using the CPAP function of the ventilator to an airway pressure of 45cmH2O for 20 s, with an interval of 1 min in between) could be included in combination with suction to improve oxygenation after endo tracheal suction procedure.

Strong recommendation: The implementation of this recommendation is not associated with extra cost or an increased burden

On moderate quality evidence: One randomized crossover study (Dyer et al 2003) downgraded due to imprecision of data.

Post your comments

Post Best practice recommendations for the management of intubated and ventilated patients diagnosed with ARDS/ALI : STRENGTH OF RECOMMENDATION 1: The meta-analysis (Alsighir et al 2008) based on the results of 5 high quality RCT’s concluded that prone positioningyour comments

Post your comments

Post your comments

Post your comments

Post your comments

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download