Clinical Guidelines for the Manual Titration of Positive Airway Pressure in Patients with Obstructive Sleep Apnea

Abstract

Summary:

Positive airway pressure (PAP) devices are used to treat patients with sleep related breathing disorders (SRBDs), including obstructive sleep apnea (OSA). After a patient is diagnosed with OSA, the current standard of practice involves performing attended polysomnography (PSG), during which positive airway pressure is adjusted throughout the recording period to determine the optimal pressure for maintaining upper airway patency. Continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BPAP) represent the two forms of PAP that are manually titrated during PSG to determine the single fixed pressure of CPAP or the fixed inspiratory and expiratory positive airway pressures (IPAP and EPAP, respectively) of BPAP for subsequent nightly usage. A PAP Titration Task Force of the American Academy of Sleep Medicine reviewed the available literature. Based on this review, the Task Force developed these recommendations for conducting CPAP and BPAP titrations. Major recommendations are as follows: (1) All potential PAP titration candidates should receive adequate PAP education, hands-on demonstration, careful mask fitting, and acclimatization prior to titration. (2) CPAP (IPAP and/or EPAP for patients on BPAP) should be increased until the following obstructive respiratory events are eliminated (no specific order) or the recommended maximum CPAP (IPAP for patients on BPAP) is reached: apneas, hypopneas, respiratory effort-related arousals (RERAs), and snoring. (3) The recommended minimum starting CPAP should be 4 cm H₂O for pediatric and adult patients, and the recommended minimum starting IPAP and EPAP should be 8 cm H₂O and 4 cm H₂O, respectively, for pediatric and adult patients on BPAP. (4) The recommended maximum CPAP should be 15 cm H₂O (or recommended maximum IPAP of 20 cm H₂O if on BPAP) for patients <12 years, and 20 cm H₂O (or recommended maximum IPAP of 30 cm H₂O if on BPAP) for patients ≥12 years. (5) The recommended minimum IPAP-EPAP differential is 4 cm H₂O and the recommended maximum IPAP-EPAP differential is 10 cm H₂O (6) CPAP (IPAP and/or EPAP for patients on BPAP depending on the type of event) should be increased by at least 1 cm H₂O with an interval no shorter than 5 min, with the goal of eliminating obstructive respiratory events. (7) CPAP (IPAP and EPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 1 obstructive apnea is observed for patients <12 years, or if at least 2 obstructive apneas are observed for patients ≥12 years. (8) CPAP (IPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 1 hypopnea is observed for patients <12 years, or if at least 3 hypopneas are observed for patients ≥12 years. (9) CPAP (IPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 3 RERAs are observed for patients <12 years, or if at least 5 RERAs are observed for patients ≥12 years. (10) CPAP (IPAP for patients on BPAP) may be increased from any CPAP (or IPAP) level if at least 1 min of loud or unambiguous snoring is observed for patients <12 years, or if at least 3 min of loud or unambiguous snoring are observed for patients ≥12 years. (11) The titration algorithm for split-night CPAP or BPAP titration studies should be identical to that of full-night CPAP or BPAP titration studies, respectively. (12) If the patient is uncomfortable or intolerant of high pressures on CPAP, the patient may be tried on BPAP. If there are continued obstructive respiratory events at 15 cm H₂O of CPAP during the titration study, the patient may be switched to BPAP. (13) The pressure of CPAP or BPAP selected for patient use following the titration study should reflect control of the patient's obstructive respiration by a low (preferably <5 per hour) respiratory disturbance index (RDI) at the selected pressure, a minimum sea level SpO₂ above 90% at the pressure, and with a leak within acceptable parameters at the pressure. (14) An optimal titration reduces RDI <5 for at least a 15-min duration and should include supine REM sleep at the selected pressure that is not continually interrupted by spontaneous arousals or awakenings. (15) A good titration reduces RDI ≤10 or by 50% if the baseline RDI <15 and should include supine REM sleep that is not continually interrupted by spontaneous arousals or awakenings at the selected pressure. (16) An adequate titration does not reduce the RDI ≤10 but reduces the RDI by 75% from baseline (especially in severe OSA patients), or one in which the titration grading criteria for optimal or good are met with the exception that supine REM sleep did not occur at the selected pressure. (17) An unacceptable titration is one that does not meet any one of the above grades. (18) A repeat PAP titration study should be considered if the initial titration does not achieve a grade of optimal or good and, if it is a split-night PSG study, it fails to meet AASM criteria (i.e., titration duration should be >3 hr).

Citation:

Kushida CA; Chediak A; Berry RB; Brown LK; Gozal D; Iber C; Parthasarathy S; Quan SF; Rowley JA; Positive Airway Pressure Titration Task Force of the American Academy of Sleep Medicine. Clinical guidelines for the manual titration of positive airway pressure in patients with obstructive sleep apnea. J Clin Sleep Med 2008;4(2):157–171.

1.0 INTRODUCTION

Positive airway pressure (PAP) is a standard treatment for patients with obstructive sleep apnea (OSA), a sleep related breathing disorder characterized by full or partial occlusion of the upper airway during sleep. Standard sleep medicine practice involves manual pressure adjustment by a sleep technologist during attended laboratory polysomnography (PSG) to eliminate obstructive respiratory-related events (apneas, hypopneas, respiratory effort-related arousals [RERAs], and snoring). A PAP delivery system consists of three main components: a PAP device; a nasal, oral, or oronasal interface (i.e., nasal mask, nasal pillows, full-face mask) held snug to the face by headgear; and a flexible hose that connects the device to the interface. A PAP device is basically an air pump (fan-driven or turbine system) that draws in external, filtered air and delivers pressurized airflow, which is adjustable by varying the pressure valve diameter or fan/turbine speed. PAP devices are divided into four basic types depending on their pressure delivery system: (1) continuous positive airway pressure (CPAP), which delivers a single, fixed pressure to the patient during the night; (2) bilevel positive airway pressure (BPAP), which delivers a higher inspiratory PAP (IPAP) than expiratory PAP (EPAP); (3) autotitrating positive airway pressure (APAP), which automatically increases CPAP or BPAP (IPAP/EPAP) as needed to maintain airway patency and then decreases the pressure if no abnormal respiratory events are detected within a set period of time; and (4) adaptive servoventilation (ASV), which uses a servocontroller that automatically adjusts pressure by breath-by-breath analysis to maintain a steady minute ventilation especially in heart failure patients with central sleep apnea and/or Cheyne-Stokes respiration.

A 2004 national survey of 196 board certified sleep physicians regarding APAP device prescriptions based upon point-prevalence estimates revealed that only 4% of PAP devices prescribed were APAP and that 30% of board certified sleep physicians reported having never prescribed APAP devices.¹ As more validation and reliability studies in diverse settings are being conducted, it is assumed that sleep medicine specialists are gradually becoming more accepting of the use of APAP devices.^2–4 Nevertheless, manual titration of CPAP or BPAP is currently the gold standard for selection of the optimal (effective) pressure for CPAP and BPAP (IPAP/EPAP), respectively, and the goal of this report was to develop recommendations that reflect current knowledge and practice of this procedure.

The American Academy of Sleep Medicine (AASM) has published practice parameters on the indications for PSG^5,6 (i.e., the utility of PSG for the diagnosis of sleep-related breathing disorders) and on the indications for CPAP and BPAP in the treatment of airway obstruction in OSA.⁷ Lastly, in 2007, the AASM published a new scoring manual that defines the abnormal respiratory events (e.g., apneas, hypopneas, RERAs), which are used for PAP titration.⁸ The present recommendations add to but do not modify any of these previously published guidelines and definitions.

2.0 METHODS

The AASM Board of Directors approved the development of PAP titration recommendations in April 2007, and approved the appointments of Task Force members in July 2007. An initial literature search was conducted by Drs. Alejandro Chediak and Vincenzo Novara on November 27, 2006 using the key words: CPAP initiation, CPAP titration, CPAP adjustment, PAP titration, bilevel positive pressure titration, bi-level pressure titration, BiPAP titration, and BiPAP adjustment. This search yielded 372 results, of which 26 relevant abstracts and articles were obtained and reviewed. Supplemental literature searches were conducted on June 29, 2007 and December 5, 2007 using the same key words as in the original search; an additional literature search was conducted on November 30, 2007 using the same key words plus the key word: children. These supplemental searches yielded an additional 82 results, of which 7 additional relevant articles were obtained and reviewed. All literature searches were computer-based using PubMed. The objective was to identify all studies that described PAP titration protocols and that were published in English from 1968 up to the date of the searches. Twenty-two additional relevant publications were obtained after reviewing the bibliographies of the publications collected through the original and supplemental searches. Lastly, the Task Force also reviewed PAP titration protocols developed by industry for background information; however, these protocols were not used to support the recommendations.

All relevant publications were assigned an evidence level based on the classification shown in Table 1.

Table 1.

AASM Classification of Evidence

Evidence Levels	Study Design
I	Randomized well-designed trials with low alpha and beta error*
II	Randomized trials with high alpha and beta error*
III	Nonrandomized concurrently controlled studies
IV	Nonrandomized historically controlled studies
V	Case series

Adapted from Sackett⁹

^*Alpha error refers to the probability (generally set at 95% or greater) that a significant outcome (e.g., p < 0.05) is not a result of chance occurrence. Beta error refers to the probability (generally set at 80% to 90% or greater) that a nonsignificant result (e.g., p > 0.05) is the correct conclusion of the study or studies. The estimation of beta error is generally the result of a power analysis. The power analysis includes a sample size analysis to project the size of the study population necessary to ensure that significant differences will be observed if actually present.

Potential recommendations reflected evidence for reliability and validity as assessed by the Task Force following literature review, or comprised uncertainties in the literature that needed resolution by consensus. The Rand/UCLA Appropriateness Method¹⁰ was selected as the consensus process for use by the Task Force given its use by the AASM Standards of Practice Committee (SPC) and the AASM Scoring Manual Task Forces, and also because the relative paucity of evidence warranted a formal consensus process. The first conference call of the Task Force was held on July 23, 2007 to discuss the consensus process and to develop a ballot comprised of possible recommendations. In order to encourage single recommendations, the ballots were constructed when possible to address mutually exclusive options. For balloting, the possible recommendations were rated on a 9-point scale for appropriateness and a 4-letter rank for specifying a judgment regarding whether the decision was being made on evidence vs. opinion. The “classic” definition of agreement was assessed using definitions from the RAND manual:

• Agreement for or against: No more than 2 Task Force members rate the indication outside the 3-point region (1–3, 4–6, 7–9) containing the median.

• Disagreement: At least 3 Task Force members rate the indication in the 1–3 region, and at least 3 Task Force members rate it in the 7–9 region.

• Indeterminate: Criteria are not met for agreement or disagreement.

The first round ballot was distributed to the Task Force on August 6, 2007 and was completed by September 1, 2007; Task Force members completed this round of voting individually without discussion. The first round ballot results were distributed to the Task Force on September 14, 2007. A conference call for the second round of voting was held on September 24, 2007, at which time there was discussion of the recommendations and the results of the first vote; consensus was achieved on all recommendations during this second round of voting. The recommendations in section 4.0 were developed based on the voting results and were subsequently reviewed by two outside reviewers, the Chair of the AASM Standards of Practice Committee, and the AASM Board of Directors. The Executive Committee of the AASM Board of Directors approved these recommendations on February 8, 2008.

All members of the Task Force and the Board of Directors completed detailed conflict-of-interest statements; none had Level 1 conflicts in the scope of their roles. Most participants in the development of this report are directors or members of sleep disorders centers, and many have substantial experience with PAP titration. These recommendations should not be considered inclusive of all proper methods of care or exclusive of other methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific care must be made by the clinician in light of the individual circumstances presented by the patient and the availability of diagnostic and treatment options and resources.

The AASM expects these recommendations to have a positive impact upon the practice of sleep medicine, patient treatment outcomes, and health care costs. These recommendations reflect the state of knowledge at publication and will be reviewed, updated, and revised as new information becomes available. It is important to note that the recommendations published in this report are not practice parameters, since the majority of these recommendations do not achieve the evidence level of typical practice parameters. Instead, all recommendations were developed using the consensus process and the evidence grading was used only to indicate the level of evidence available to support the recommendations. AASM levels of recommendations (Table 2) are indicated in parentheses after recommendations that are based on published practice parameters; those recommendations that were not based on published parameters are labeled as “(Consensus).”

Table 2.

AASM Levels of Recommendations

Term	Definition
Standard	This is a generally accepted patient care strategy that reflects a high degree of clinical certainty. The term standard generally implies the use of level I evidence that directly addresses the clinical issue, or overwhelming level II evidence.
Guideline	This is a patient care strategy that reflects a moderate degree of clinical certainty. The term guideline implies the use of level II evidence or a consensus of level III evidence.
Option	Recommendation with less evidence than guideline for which agreement was reached in a standardized consensus process based on available information.

Adapted from Eddy¹¹ and Iber et al.⁸

3.0 BACKGROUND

The manual titration of positive airway pressure has been conducted for over a quarter of a century,¹² yet no standardized protocols exist for this procedure.¹³ A survey of accredited sleep centers reviewed titration protocols from 51 accredited centers and found that the procedures described for PAP titration varied widely among the centers; 22% of these centers did not have a written protocol.¹⁴ The lack of standardization results in clinicians and technologists from different sleep laboratories developing their own protocols¹⁵ or relying on protocols obtained from industry or other sleep laboratories. When a standardized protocol is implemented, the optimal pressure for CPAP can be reproducible; one study revealed a Spearman correlation coefficient of 0.89 for the optimal pressure selected for 2 consecutive CPAP titration nights in 50 patients with OSA.¹⁶ However, very few PAP titration protocols have been published in the literature, and there is a question as to what one would use or measure to advocate or support one particular protocol over another. Thus, the goal of this Task Force was the development of an evidence- and consensus-based standardized PAP titration protocol, with the underlying concept that a successful titration is one in which there is an optimized trade-off between increasing pressure to yield efficacy in elimination of respiratory events and decreasing pressure to minimize emergence of pressure-related side effects.¹⁷

The optimal pressure selected for an OSA patient during a PAP titration study is subject to interindividual variability, i.e., a pressure that controls the respiratory events of one patient may inadequately control those of another patient.¹⁸ There are several factors that have been identified as potentially influencing optimal pressure, such as rapid eye movement (REM) sleep amounts,¹⁹ the length of the soft palate,¹⁸ and the degree of respiratory effort.¹⁸ Additionally, one might reason that the level of optimal PAP is correlated with OSA severity and/or obesity; i.e., higher levels of PAP would be needed to control respiratory events in patients with severe OSA and/or those who are obese. However, this premise has not been consistently supported in the literature; although there are some studies demonstrating a good correlation between the level of optimal CPAP and the apnea-hypopnea index (AHI)^20,21 or obesity,²¹ a significant correlation for optimal CPAP and AHI has been observed only in patients whose apneas are dependent on body position.²² Mathematical equations incorporating measures of OSA severity (AHI) and obesity (i.e., body mass index and neck circumference) have been developed to predict the optimal level of CPAP^21,23,24 in order to theoretically achieve a higher rate of successful CPAP titrations by eliminating the need for multiple pressure changes at low pressure levels and to decrease the risk of insufficient time to perform an adequate titration study. However, two studies have independently failed to confirm the accuracy of these equations in predicting the prescribed CPAP level,^25–27 prompting the authors of one of these studies to comment that this failure “reaffirms the need for a CPAP titration study to prescribe the optimal therapy to the patient.”²⁵

Two types of PAP devices (CPAP and BPAP) are included in these titration recommendations, and BPAP as described in this report refers to BPAP set in spontaneous mode unless otherwise specified. Data regarding usefulness of other PAP device types or device features were not reviewed; although specific indications for adaptive servoventilation are discussed, a titration protocol for this device is not described since this type of ventilation was considered beyond the scope of this report. The recommendations in this report pertain only to nighttime PAP titration studies, although there is an emerging body of literature that indicates that diurnal and nocturnal titration results in comparable therapeutic pressures, equivalent resolution of sleep disordered breathing, and improvement in subjective sleepiness after 1-12 weeks of treatment, particularly for patients with severe OSA.^28–30

This report uses the following terminology. Unless stated otherwise OSA is used synonymously with obstructive sleep apnea syndrome (OSAS), obstructive sleep apnea-hypopnea syndrome (OSAHS), and obstructive forms of either sleep disordered breathing (SDB) or sleep related breathing disorder (SRBDs). Other SRBDs are not addressed except when relevant to adaptive servoventilation treatment. The respiratory disturbance index (RDI) refers to the total of apneas, hypopneas, and RERAs per hour of sleep, and for this report, this term is not synonymous with the AHI, which refers to the total of apneas and hypopneas per hour of sleep. Mild, moderate and severe OSA are defined according to following criteria in adults: mild, RDI 5 to ≤15; moderate, RDI 15 to 30; and severe, RDI >30.³¹ In children <12 years of age: mild, RDI 1 to <5; moderate, RDI 5 to <10; and severe, RDI >10.^8,32–34

4.0 RECOMMENDATIONS

The following are recommendations of the PAP Titration Task Force and the AASM Board of Directors. The scope of these PAP titration recommendations is restricted to adult (≥12 years) and pediatric (<12 years) patients with obstructive sleep apnea; these recommendations do not apply to patients with conditions such as neuromuscular disease or intrinsic lung disease. Summaries and evidence levels of published PAP titration protocols for adult and pediatric patients are listed in Tables 3a and 3b (see JCSM website: www.aasmnet.org/JCSM), respectively, and CPAP and BPAP titration algorithms for adult and pediatric patients during full- or split-night titration studies are depicted in Figures 1–4. The optimal setting for the titration of CPAP or BPAP is in an AASM-accredited sleep center or laboratory, with the titration protocol implemented by registered polysomnographic technologists and review of the titration study (including pressure selection) by a board certified sleep specialist. Additionally, the definitions, protocols, procedures, and indications for the diagnosis and management of OSA as specified in the AASM practice parameters for polysomnography⁵ and PAP,⁷ and the AASM Manual for the Scoring of Sleep and Associated Events⁸ (i.e., respiratory rules) should be followed. It is understood that the recommendations for minimum and maximum PAP may be constrained by the specific PAP device used during the titration protocol. Lastly, the expectation of the Task Force is that these recommendations should not be followed in a “cookbook” manner; instead, sleep technologists and clinicians should combine their experience and judgment with the application of these recommendations to attain the best possible titration in any given patient.

Figure 1.

CPAP Titration Algorithm for Patients <12 years During Full- or Split-Night Titration Studies. Note: Upward titration at ≥ 1-cm increments over ≥ 5-min periods is continued according to the breathing events observed until ≥ 30 min without breathing events is achieved.

* A higher starting CPAP may be selected for patients with an elevated BMI and for retitration studies

** The patient should also be tried on BPAP if the patient is uncomfortable or intolerant of high CPAP

Figure 2.

CPAP Titration Algorithm for Patients ≥12 years During Full- or Split-Night Titration Studies. Note: Upward titration at ≥ 1-cm increments over ≥ 5-min periods is continued according to the breathing events observed until ≥ 30 min without breathing events is achieved.

* A higher starting CPAP may be selected for patients with an elevated BMI and for retitration studies

** The patient should also be tried on BPAP if the patient is uncomfortable or intolerant of high CPAP

Figure 3.

BPAP Titration Algorithm for Patients <12 years During Full- or Split-Night Titration Studies. Note: Upward titration of IPAP and EPAP ≥ 1 cm H2O for apneas and IPAP ≥ 1 cm for other events over ≥ 5-min periods is continued until ≥ 30 min without breathing events is achieved. A decrease in IPAP or setting BPAP in spontaneous-timed mode with backup rate may be helpful if treatment-emergent central apneas are observed.

* A higher starting IPAP and EPAP may be selected for patients with an elevated BMI and for retitration studies. When transitioning from CPAP to BPAP, the minimum starting EPAP should be set at 4 cm H2O or the CPAP level at which obstructive apneas were eliminated. An optimal minimum IPAP-EPAP differential is 4 cm H2O and an optimal maximum IPAP-EPAP differential is 10 cm H2O.

Figure 4.

BPAP Titration Algorithm for Patients ≥12 years During Full- or Split-Night Titration Studies. Note: Upward titration of IPAP and EPAP ≥ 1 cm H2O for apneas and IPAP ≥ 1 cm for other events over ≥ 5-min periods is continued until ≥ 30 min without breathing events is achieved. A decrease in IPAP or setting BPAP in spontaneous-timed mode with backup rate may be helpful if treatment-emergent central apneas are observed.

* A higher starting IPAP and EPAP may be selected for patients with an elevated BMI and for retitration studies. When transitioning from CPAP to BPAP, the minimum starting EPAP should be set at 4 cm H2O or the CPAP level at which obstructive apneas were eliminated. An optimal minimum IPAP-EPAP differential is 4 cm H2O and an optimal maximum IPAP-EPAP differential is 10 cm H2O.

4.1 General Recommendations for Conducting PAP Titration Studies in Pediatric or Adult Patients with Obstructive Sleep Apnea

4.1.1 All Potential PAP Titration Candidates (Including Those Candidates Prior to a Diagnostic Study Where the Clinical Suspicion of OSA is High and a Split-Night Study is a Possibility) Should Receive Adequate PAP Education, Hands-On Demonstration, Careful Mask Fitting, and Acclimatization Prior to Titration (Standard).

This recommendation is based on Standard-Level Recommendation 4.3.4 (“The addition of a systematic educational program is indicated to improve PAP utilization”) in the 2006 practice parameters for the use of PAP devices⁷ and consensus agreement by the PAP Titration Task Force. The Task Force recommends that the indications, rationale for use, and side effects should be discussed in detail with the patient or caregiver preferably prior to the PAP titration study; parts and assembly, optional equipment, importance of daily/nightly use, adherence issues, necessity of cleaning the equipment, and implications of the purchase/rental of the equipment (when applicable) should be discussed in detail with the patient or caregiver, preferably following the PAP titration study. The patient should be carefully fitted for the interface (i.e., nasal mask, nasal pillows, full-face/oronasal mask) with the goals of maximizing comfort, compensating for significant nasal obstruction, and minimizing leak prior to the PAP titration. There should be several different types of PAP interfaces (i.e., nasal mask, nasal pillows, full-face/oronasal mask) and accessories (chinstrap, heated humidifier) available if the patient encounters problems (e.g., mouth leak, nasal congestion, or oronasal dryness) during the night. The patient should be acclimated to the PAP equipment (i.e., wearing the interface with the pressure on) prior to “lights off.”³⁵ For pediatric patients, in addition to the above, pediatric interfaces should be available³⁶ and behavioral modification techniques may be implemented to increase the tolerability and potential adherence to PAP equipment,^37–39 since children frequently have problems adjusting to PAP.

4.1.2 Recording the Airflow Signal Generated by the PAP Device or Estimating Airflow by Measurement of the Pressure Difference Between the Mask and the Outlet of the Machine Using a Pressure Transducer, with or without Square Root Transformation of the Signal, are Acceptable Methods for Detecting Apneas or Hypopneas (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Consensus-Level Respiratory Rule 1.B (i.e., a nasal air pressure transducer with or without square root transformation of the signal is the preferred sensor for detection of airflow for identification of a hypopnea during diagnostic [non-PAP] PSG) in the AASM Scoring Manual.⁸ However, during PAP titrations, the use of a standard nasal pressure sensor placed under the nares is problematic due to the difficulty in obtaining a good PAP mask seal since the tubing has to pass underneath the mask. Thus, estimation of airflow for detection of apneas or hypopneas by one of the two techniques specified above is acceptable; care should be exercised to ensure that the signal is accurately recorded. PAP devices designed for use in polysomnography generate a flow signal based on accurate flow sensors within the device and the majority also provide a signal reflecting an estimate of leak.

4.1.3 Nasal Airflow Obtained from a Thermistor or Thermocouple Placed Under the PAP Mask is not an Acceptable Method for Detecting Apneas or Hypopneas (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. An oronasal thermal sensor is the preferred primary sensor to detect absence of airflow for identification of an apnea during diagnostic (non-PAP) PSG.⁸ However, it is not the preferred sensor to detect airflow for identification of a hypopnea (see Recommendation 4.1.2) and the placement of this sensor under a PAP mask for detection of airflow is not recommended.

4.1.4 Respiratory Effort-Related Arousals May Be Estimated by Flattening of the Inspiratory Airflow Profile Associated with an Arousal When Airflow Changes Do Not Meet Criteria for apneas or Hypopneas (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. As specified in the AASM Scoring Manual, a respiratory effort-related arousal (RERA) in adults is defined as a sequence of breaths lasting at least 10 sec characterized by increasing respiratory effort or flattening of the nasal pressure waveform leading to an arousal from sleep when the sequence of breaths does not meet criteria for an apnea or hypopnea.⁸ The scoring rules for pediatric RERAs when using a nasal pressure sensor requires a discernible fall in the amplitude of the signal from the sensor; a duration of at least 2 breath cycles; accompanying snoring, noisy breathing, elevation in the end-tidal CO₂, transcutaneous CO₂, or visual evidence of increased work of breathing; and termination by an arousal.⁸ The contour of inspiratory flow tracing from a PAP system can be used to infer the presence of elevated upper airway resistance and flow limitation,^40,41 and this contour appears to be the simplest variable that best correlates with the lowest esophageal pressure during PAP titration.⁴² For the assessment of respiratory effort during PAP titration, esophageal manometry or nasal pressure plus inductance plethysmography can be used in pediatric and adult patients, although the former technique may be more problematic given partial occlusion of one of the nares and difficulty obtaining a good PAP mask seal with the esophageal catheter and poorer adherence in the pediatric population.

4.1.5 Sawtooth Patterns in the Unfiltered Airflow or Mask Pressure Tracings and/or Detection of Vibration by Piezoelectric Transducers or Microphones Applied to the Neck are Acceptable Methods for Detecting Snoring (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. The output from most PAP devices while accurate for assessing airflow and flow limitation is often too filtered or undersampled to display snoring.

4.2 Recommendations for Conducting CPAP Titration Studies in Pediatric or Adult Patients with Obstructive Sleep Apnea

4.2.1 General Recommendations for CPAP Titration Studies

4.2.1.1 CPAP should be increased until the following obstructive respiratory events are eliminated (no specific order) or the recommended maximum CPAP is reached: apneas, hypopneas, RERAs, and snoring (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Guideline-Level evidence (3 level II studies,^43–45 2 level III studies,^46,47 and 5 level V studies^42,48–51). The Task Force recommends that SaO₂ desaturation-resaturation events occurring without associated obstructive respiratory events should not be considered in the decision to increase CPAP in pediatric and adult patients.

4.2.1.2 The recommended minimum starting CPAP should be 4 cm H₂O in pediatric and adult patients (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Standard-Level evidence (1 level I study,⁵² 4 level II studies,^44,45,53,54 4 level III studies,^16,47,55,56 2 level IV studies,^35,57 and 4 level V studies^49,58–60).

4.2.1.3 The recommended maximum CPAP should be 15 cm H₂O for patients <12 years and 20 cm H₂O for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Option-Level evidence (1 level II study⁵³ [adult patients], 1 level III study⁶¹ [adult patients], 2 level V studies^40,62 [adult and pediatric patients]). If there are continued obstructive respiratory events at 15 cm H₂O of CPAP for either adult or pediatric patients during the titration study, the patient may be switched to BPAP (see Recommendation 4.3.1.1)

4.2.1.4 Methodology to determine CPAP a priori has insufficient evidence, although a higher starting CPAP may be selected for patients with an elevated body mass index and for retitration studies (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Option-Level evidence (1 level III study that found that the amount of CPAP pressure was correlated with body mass index at baseline [ρ = 0.32, p <0.001]²⁰ and 1 level V study that indicates that body mass indices were significantly higher in patients who required higher CPAP levels to abolish their apnea²¹).

4.2.2 Full Night CPAP Titration Studies

4.2.2.1 CPAP should be increased by at least 1 cm H₂O with an interval no shorter than 5 min, with the goal of eliminating obstructive respiratory events (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Standard-Level evidence (2 level I studies,^52,63 7 level II studies,^{43,44,53,54,64–66} 8 level III studies,^{16,46,47,55,56,61,67,68} 5 level IV studies,^{25,35,57,69,70} 21 level V studies,^{18,21,24,42,48,49,51,59,60,62,71–81}). The studies reported pressure increments of 1-2.5 cm H₂O, and 11 of these studies^{16,25,26,42,43,52,55,56,59,74,77} specify a time duration ≥5 min. There are insufficient data to recommend increasing CPAP by increments of more than 2.5 cm H₂O.

4.2.2.2 CPAP should be increased (according to the criterion in Recommendation 4.2.2.1) if at least 1 obstructive apnea is observed for patients <12 years or if at least 2 obstructive apneas are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. A lower pressure is required to treat apneas compared to the pressure required to treat other respiratory events.⁸²

4.2.2.3 CPAP should be increased (according to the criterion in Recommendation 4.2.2.1) if at least 1 hypopnea is observed for patients <12 years or if at least 3 hypopneas are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.2.2.4 CPAP should be increased (according to the criterion Recommendation 4.2.2.1) if at least 3 RERAs are observed for patients <12 years or if at least 5 RERAs are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.2.2.5 CPAP may be increased (according to the criterion in Recommendation 4.2.2.1) if at least 1 min of loud or unambiguous snoring is observed for patients <12 years or if at least 3 min of loud or unambiguous snoring are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. The utility of titrating CPAP to eliminate snoring was demonstrated in a limited study of non-apneic patients. Although a minority of these patients accepted CPAP use and their subsequent CPAP adherence was poor, 73% of these patients nevertheless reported improvement in their subjective daytime sleepiness after using CPAP for a six-month period.⁸³

4.2.2.6 “Exploration” of CPAP above the pressure at which control of abnormalities in respiratory parameters is achieved should not exceed 5 cm H₂O (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. CPAP exploration does have utility; upper airway resistance can be four times normal despite selection of a pressure that eliminates apneas and hypopneas,⁴² and this residual high airway resistance can lead to repetitive arousals and insomnia.⁸⁴ Reduction of this resistance has been demonstrated by increasing pressure until esophageal pressure swings (if measured) or the shape of the inspiratory flow limitation curve are normalized,^40,84,85 or by increasing pressure by 2 cm H₂O¹⁷ but no higher than by 5 cm H₂O.

4.2.2.7 If the patient awakens and complains that the pressure is too high, the pressure should be restarted at a lower pressure, chosen as one that the patient reports is comfortable enough to allow return to sleep (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.2.2.8 “Down” titration is not required but may be considered as an option (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Option-Level evidence (2 level III studies^16,47). A “down” titration is recommended due to the “hysteresis” phenomenon:⁴⁰ during upward titration the PAP level at which flow limitation disappears is 2-5 cm H₂O higher than the level at which it reappears during downward titration. If a “down” titration is implemented, the Task Force recommends at least one “up-down” CPAP titration (1 cycle) should be conducted during the night. It should be conducted when at least 30 min has elapsed without obstructive respiratory events. CPAP should be decreased by more than 1 cm H₂O with an interval no shorter than 10 min, until there is reemergence of obstructive respiratory events. There is also limited evidence that an “up-down-up” titration protocol should be considered.⁴⁹ One study with 85 OSA patients used a CPAP protocol in which the pressure was increased by 1 cm H₂O in a stepwise fashion until respiratory events disappeared (effective pressure 1, Peff₁); the pressure level was then decreased by increments of 1 cm H₂O until respiratory abnormalities reappeared. The pressure was re-increased by increments of 1 cm H₂O to normalize respiration (Peff₂). The pressure obtained after the “down” titration had to be re-increased in 79 patients due to snoring (n = 26), flow limitations associated with arousals (n = 32), obstructive hypopneas (n = 19), and obstructive apneas (n = 2). The Peff₂ level was significantly lower than Peff₁ with a mean difference of 0.6 (1.5) cm H₂O (95% confidence interval, 0.29–0.93).

4.2.3 Split-Night CPAP Titration Studies

4.2.3.1 The titration algorithm for split-night CPAP titration studies should be identical to that of full-night CPAP titration studies (Guideline).

This recommendation is based on Guideline-Level Recommendation 4.2.1 (“A full-night, attended polysomnography performed in the laboratory is the preferred approach for titration to determine optimal positive airway pressure; however, split-night, diagnostic-titration studies are usually adequate”) in the 2006 practice parameters for the use of PAP devices⁷ and consensus agreement by the PAP Titration Task Force. Studies that have compared adequacy of prescribed pressure, CPAP adherence, and patient acceptance have found no significant differences for adult patients undergoing full-night vs. split-night CPAP titration studies,^{46,69,86–88} with the possible exception that pressures determined from split-night studies may be lower for patients with mild-to-moderate OSA who may not manifest the maximal severity of their condition during the first portion of the night.^25,73 It may be prudent to increase CPAP at larger increments (i.e., 2 or 2.5 cm H₂O) given the shorter CPAP titration duration in split-night vs. full-night studies. Of note, there are insufficient data to make any recommendations for split-night CPAP titration studies in children <12 years.

4.3 Recommendations for Conducting Bilevel PAP (BPAP) Titration Studies in Pediatric or Adult Patients with Obstructive Sleep Apnea

4.3.1 General Recommendations for BPAP Titration Studies

4.3.1.1 If the patient is uncomfortable or intolerant of high pressures on CPAP, the patient may be tried on BPAP. If there are continued obstructive respiratory events at 15 cm H₂O of CPAP during the titration study, the patient may be switched to BPAP (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Option-Level evidence (1 level IV study⁴⁰ and 1 level V study⁶²). However, this recommendation does not imply that BPAP is more effective than CPAP at maintaining upper airway patency. Additionally, efforts should be made to explore why the patient is uncomfortable or intolerant of high pressures on CPAP and to remedy the situation before trying the patient on BPAP.

4.3.1.2 BPAP (IPAP and/or EPAP, depending on the type of obstructive respiratory event) should be increased until the following events are eliminated (no specific order) or the recommended maximum IPAP is reached: apneas, hypopneas, RERAs, and snoring (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Guideline-Level evidence (1 level I study⁵² and 1 level III study⁴⁶). The Task Force recommends that SaO₂ desaturation-resaturation events occurring without associated obstructive respiratory events should not be considered in the decision to increase IPAP and/or EPAP in pediatric and adult patients.

4.3.1.3 The recommended minimum starting IPAP and EPAP should be 8 cm H₂O and 4 cm H₂O, respectively, in pediatric and adult patients (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Guideline-Level evidence (1 level I study⁵² for the minimum starting EPAP in adult patients). In addition, when switching from CPAP to BPAP, the Task Force recommends that the minimum starting EPAP should be set at 4 cm H₂O or the CPAP level at which obstructive apneas were eliminated.

4.3.1.4 The recommended maximum IPAP should be 20 cm H₂O for patients <12 years or 30 cm H₂O for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. There is also evidence from the critical care literature indicating that an excess of 30 cm H₂O of upper airway pressure may increase the risk for barotrauma and other morbidities.^89,90

4.3.1.5 Methodology to determine IPAP or EPAP a priori has insufficient evidence, although a higher starting IPAP or EPAP may be selected for patients with an elevated BMI and for retitration studies (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. As in the case of CPAP, a higher starting IPAP or EPAP may be needed for patients with an elevated BMI (see Recommendation 4.2.1.4).

4.3.1.6 The recommended minimum IPAP-EPAP differential is 4 cm H₂O and the recommended maximum IPAP-EPAP differential is 10 cm H₂O (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Guideline-Level evidence (1 level I study⁵² for the minimum IPAP-EPAP differential in adult patients).

4.3.2 Full-Night BPAP Titration Studies

4.3.2.1 IPAP and/or EPAP (depending on the type of obstructive respiratory event) should be increased by at least 1 cm H₂O apiece with an interval no shorter than 5 min, with the goal of eliminating obstructive respiratory events (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and Guideline-Level evidence (1 level II study,⁶⁶ 1 level III study,⁴⁶ and 2 level V studies^71,74).

4.3.2.2 IPAP and EPAP should be increased (according to the criterion in Recommendation 4.3.2.1) if at least 1 obstructive apnea is observed for patients <12 years or if at least 2 obstructive apneas are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. As in the case of CPAP, a lower pressure is required to treat apneas compared to the pressure required to treat other respiratory events (see Recommendation 4.2.2.2); however, there is 1 level II study⁵³ and 1 level V study⁷¹ that used increases in both IPAP and EPAP to eliminate apneas.

4.3.2.3 IPAP should be increased (according to the criterion in Recommendation 4.3.2.1) if at least 1 hypopnea is observed for patients <12 years or if at least 3 hypopneas are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.3.2.4 IPAP should be increased (according to the criterion in Recommendation 4.3.2.1) if at least 3 RERAs are observed for patients <12 years or if at least 5 RERAs are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.3.2.5 IPAP may be increased (according to the criterion in Recommendation 4.3.2.1) if at least 1 min of loud or unambiguous snoring is observed for patients <12 years or if at least 3 min of loud or unambiguous snoring are observed for patients ≥12 years (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. As in the case of CPAP, the utility of titrating PAP to treat snoring may be reflected in improvement in patients' subjective daytime sleepiness (see Recommendation 4.2.2.5).

4.3.2.6 “Exploration” of IPAP above the pressure at which control of abnormalities in respiratory parameters is achieved should not exceed 5 cm H₂O (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. As in the case of CPAP, IPAP exploration does have utility (see Recommendation 4.2.2.6).

4.3.2.7 If the patient awakens and complains that the pressure is too high, the pressure should be restarted at a lower IPAP, chosen as one that the patient reports is comfortable enough to allow return to sleep (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.3.2.8 A decrease in IPAP or setting BPAP in spontaneous-timed (ST) mode with backup rate may be helpful if treatment-emergent central apneas (i.e., complex sleep apnea) are observed during the titration study (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.3.2.9 “Down” titration is not required but may be considered as an option (Consensus).

This recommendation and the following protocol is based on consensus agreement by the PAP Titration Task Force. As in the case of CPAP, a “down” titration is recommended for BPAP due to the “hysteresis” phenomenon⁴⁰ (see Recommendation 4.2.2.8). If a “down” titration is implemented, the Task Force recommends at least one “up-down” BPAP titration (1 cycle) should be conducted during the night. “Down” titration of IPAP and EPAP is conducted when at least 30 min has elapsed without obstructive respiratory events. IPAP should be decreased by at least 1 cm H₂O with an interval no shorter than 10 min, until there is reemergence of obstructive respiratory events. There is also limited evidence that an “up-down-up” titration protocol should be considered for CPAP⁴⁹ (see Recommendation 4.2.2.8); an “up-down-up” titration protocol should also be similarly considered for BPAP.

4.3.3 Split-Night BPAP Titration Studies

4.3.3.1 The titration algorithm for split-night BPAP titration studies should be identical to that of full-night BPAP titration studies (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. A full-night, attended polysomnography performed in the laboratory is the preferred approach for titration to determine optimal positive airway pressure; however, split-night, diagnostic-titration studies are usually adequate (Recommendation 4.2.1 [Guideline] in the practice parameters for the use of CPAP and BPAP devices published in 2006).⁹¹ Unfortunately, studies comparing factors such as patient acceptance, adequacy of prescribed IPAP/EPAP, and adherence to BPAP for patients undergoing full-night vs. split-night BPAP titration studies do not exist. It may be prudent to increase IPAP and EPAP at larger increments (i.e., 2 or 2.5 cm H₂O) given the shorter BPAP titration duration in split-night vs. full-night studies. Of note, there are insufficient data to make any recommendations for split-night BPAP titration studies in children <12 years.

4.4 Important Considerations for PAP Titration Studies in Pediatric or Adult Patients with Obstructive Sleep Apnea

4.4.1 Acceptable PAP Titration Study

4.4.1.1 The CPAP or BPAP selected for patient use following the titration study should reflect control of the patient's obstructive respiration by a low (preferably <5 per hour) RDI at the selected pressure, a minimum sea level SpO₂ above 90% at the pressure, and with a leak within acceptable parameters at the pressure (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. See Recommendation 4.4.3.2 for description of leak within acceptable parameters.

4.4.1.2 Grading system: An optimal titration reduces RDI <5 per hour for at least a 15-min duration and should include supine REM sleep at the selected pressure that is not continually interrupted by spontaneous arousals or awakenings (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and the grading system proposed by Hirshkowitz and Sharafkhaneh.⁹¹

4.4.1.3 Grading system: A good titration reduces the overnight RDI ≤10 per hour or by 50% if the baseline RDI <15 per hour and should include supine REM sleep that is not continually interrupted by spontaneous arousals or awakenings at the selected pressure (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and the grading system proposed by Hirshkowitz and Sharafkhaneh.⁹¹

4.4.1.4 Grading system: An adequate titration is one that does not reduce the overnight RDI ≤10 per hour but does reduce the RDI by 75% from baseline (especially in severe OSA patients), or one in which the titration grading criteria for optimal or good are met with the exception that supine REM sleep did not occur at the selected pressure (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and the grading system proposed by Hirshkowitz and Sharafkhaneh.⁹¹

4.4.1.5 Grading system: An unacceptable titration is one that does not meet any one of the above grades (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force and the grading system proposed by Hirshkowitz and Sharafkhaneh.⁹¹

4.4.2 Repeat PAP Titration Study

4.4.2.1 A repeat PAP titration study should be considered if the initial titration does not achieve a grade of optimal or good and, if it is a split-night PSG study, it fails to meet AASM criteria (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. As per split-night study criteria in the AASM practice parameters for the indications for PSG⁵: (a) an AHI of at least 40 is documented during a minimum of 2 hours of diagnostic PSG. Split-night studies may sometimes be considered at an AHI of 20 to 40, based on clinical judgment (e.g., if there are also repetitive long obstructions and major desaturations). However, at AHI values below 40, determination of CPAP pressure requirements, based on split-night studies, may be less accurate than in full-night calibrations. (b) CPAP titration is carried out for more than 3 hours (because respiratory events can worsen as the night progresses). (c) PSG documents that CPAP eliminates or nearly eliminates the respiratory events during REM and NREM sleep, including REM sleep with the patient in the supine position. (d) A second full night of PSG for CPAP titration is performed if the diagnosis of a SRBD is confirmed but criteria (b) and (c) are not met.

4.4.3 Leak and Comfort

4.4.3.1 PAP mask refit or readjustment should be performed whenever any significant unintentional leak is observed (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. Leakage can occur in several forms. Intentional leak is the controlled leak from the port on mask interfaces that washes out CO₂ and prevents rebreathing. Unintentional leak is characterized as a “mouth leak” (i.e., pressurized air escaping via the mouth when a nasal mask is used) or “mask leak” between the mask and the face (i.e., pressurized air escaping between the mask and the face when a nasal mask or full-face/oronasal mask is used). Unintentional leak can be minimized by mask refit or readjustment, and, in the case of “mouth leak”, addition of a chinstrap to reduce mouth opening or switching to a full-face/oronasal mask may be beneficial.^92,93 A study examining the effects of mask leak on the efficacy of BPAP therapy reported that the patients showed improved oxygenation, decreased arousal index, and increased REM sleep when this leak was minimized.⁹⁴

4.4.3.2 There is insufficient evidence for what constitutes a clinically significant leak given mask fit and other factors; however, in general, an unacceptable leak for PAP is one that is substantially higher than the leak recorded at a given pressure from a well-fitted, applied, and secured interface. The acceptable leak will always exceed the intentional leak, which depends on the applied pressure and interface type. The intentional leak vs. pressure relationship is usually supplied by the manufacturer of each interface (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. The intentional leak of all interfaces increases as pressure increases. The exact amount of leak also varies with the type of interface. This makes identification of what constitutes an unacceptable leak value very difficult. Clinical judgment based on laboratory-specific criteria or the leak vs. pressure relationship supplied by the manufacturer for a given interface is recommended. A sudden increase in leak without a pressure change should alert the technologist to a possible increase in mask/mouth leak.

4.4.3.3 Pressure waveform modification technologies may improve patient comfort and adherence with PAP (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. Complaints of a sensation of exhaling against a high pressure were reported by approximately 20% of patients receiving CPAP,⁹⁵ and it is possible that the pressure reduction during expiration on pressure-relief CPAP is more comfortable for those patients who require a higher CPAP pressure. These new technologies have had limited testing but have potential utility in patient acceptance and utilization of PAP.^{43,58,96–99}

4.4.4 Positional and Sleep Stage Factors

4.4.4.1 Ideally, the patient should be recorded in supine REM sleep for at least 15 min at the designated optimal pressure during the PAP titration study. If the patient is in REM sleep but not in the supine position while at the designated optimal pressure, the patient may be awakened and instructed to lie in the supine position (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. Optimal CPAP has been defined as the highest pressure obtained during REM sleep with the patient having slept in the supine position.⁵⁵ Since treatment-emergent central sleep apnea is more likely to occur in NREM sleep, it is also important to evaluate patients at the designated optimal pressure during NREM sleep.¹⁰⁰ There is evidence that the optimal CPAP level in the supine position is greater than 2 cm H₂O higher than the optimal CPAP needed while sleeping in the lateral position, both in REM and NREM sleep, in obese and nonobese subjects and in those younger and older than 60 years.⁵⁰ However, the decision to awaken the patient to obtain a PSG sample of supine REM must be carefully considered, since it is important that the patient be allowed to obtain adequate sleep during the titration study. This point may be supported by research demonstrating that an increase in sleep efficiency (SE) during CPAP titration compared to the diagnostic night was found to be the only significant predictor of objectively measured CPAP adherence after controlling for indices of OSA severity and sleep quality during the diagnostic night. Specifically, patients who had their SE increase used their machines an average of 2 hours more per night than those who did not have their SE increase.¹⁰¹

4.4.5 Supplemental Oxygen

4.4.5.1 Supplemental O₂ should be added during the PAP titration when, prior to the PAP titration, the patient's awake supine SpO₂ while breathing room air is ≤88%. Supplemental O₂ may also be added during the PAP titration when SpO₂ is ≤88% for ≥5 minutes in the absence of obstructive respiratory events. In both instances, supplemental O₂ should be introduced at 1 L/min and titrated upwards to achieve a target SpO₂ between 88% and 94% (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. The above recommendation is made with the understanding that pulse oximetry can overestimate the actual arterial oxygen saturation in some circumstances and that the effective inspired oxygen concentration can fall if machine flow increases due to higher leak. A slightly higher goal than 88% (90%-94%) might be prudent in some circumstances.

4.4.5.2 The minimum starting O₂ rate should be 1 L/min (both pediatric and adult patients) (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force.

4.4.5.3 O₂ rate should be increased by 1 L/min, with an interval no shorter than 15 min, until SpO₂ is between 88% and 94% (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. Similar to Recommendation 4.4.5.1, a slightly higher goal than 88% (90%–94%) might be prudent in some circumstances.

4.4.5.4 Optimally, supplemental O₂ should be connected to the PAP device outlet (using a T-connector) (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. When O₂ is introduced directly into a PAP mask, the O₂ does not have time or space to mix well with the high flow coming from the tubing, which leads to highly variable O₂ concentrations inside the mask. However, when O₂ is introduced into the tubing near the PAP device rather than directly into the mask, more constant O₂ delivery to patients using PAP would be expected.¹⁰²

4.4.5.5 “Weaning” down of O₂ supplementation by employing BPAP or by further increasing IPAP (if BPAP was already instituted and if the patient tolerates the higher inspiratory pressures) can be attempted (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. However, there is evidence from bench testing and limited human studies that measured O₂ concentration with supplemental O₂ is lower with higher CPAP, or in the case of BPAP, higher IPAP and EPAP levels, regardless of the difference between IPAP and EPAP levels.^93,102 Anything that increases machine flow (room air) has the potential to reduce the effective O₂ concentration for a given supplemental O₂ flow.

4.4.6 Adaptive Servoventilation

4.4.6.1 Adaptive servoventilation may be considered if the patient is observed to have Cheyne-Stokes respiration or if treatment-emergent central sleep apnea (i.e., complex sleep apnea) during the titration study is not eliminated by down titration of pressure (Consensus).

This recommendation is based on consensus agreement by the PAP Titration Task Force. Adaptive servoventilation is a new therapy that provides an expiratory positive airway pressure and inspiratory pressure support which is servocontrolled, based on the detection of Cheyne-Stokes respiration,¹⁰³ with a backup respiratory rate. There is controversy as to what complex sleep apnea represents,^104,105 but in one study, adaptive servoventilation has been shown to decrease respiratory events and improve objective sleep measures in patients with central sleep apnea/Cheyne-Stokes respiration, mixed sleep apnea, and complex sleep apnea.¹⁰⁶

4.4.7 Follow-up After the PAP Titration Study

4.4.7.1 PAP usage should be objectively monitored to help assure utilization (Standard).

This recommendation is based on consensus agreement by the PAP Titration Task Force, and is a slight modification of Standard-Level Recommendation 4.3.1 in the 2006 practice parameters for the use of PAP devices⁷; the current recommendation reflects objective monitoring of PAP (i.e., CPAP and BPAP), rather than only CPAP, usage.

4.4.7.2 Troubleshooting of problems encountered while on PAP, management of side effects, and methods to increase adherence should be a part of the close follow-up of the patient on PAP (Standard).

This recommendation is based on consensus agreement by the PAP Titration Task Force, and is a modification of Standard-Level Recommendation 4.4.1 (“Close follow-up for PAP usage and problems in patients with OSA by appropriately trained health care providers is indicated to establish effective utilization patterns and remediate problems, if needed. This is especially important during the first few weeks of PAP use.”) in the 2006 practice parameters for the use of PAP devices.⁷ CPAP use is improved by contact with health care providers (either clinic physician appointment or specialist nurse home visit).¹⁰⁷ However, newer approaches may represent alternatives to current practices; the use of telemedicine support (i.e., Internet-based informational support and feedback for problems experienced with CPAP use) resulted in equivalent use, functional status, and patient satisfaction at 30 days compared to traditional follow-up care.¹⁰⁸ Skipping the use of CPAP for 2 or more nights within the first week of treatment signals potential nonadherence and highlights the need for close follow-up during this particularly vulnerable period of usage.¹⁰⁹ This is especially important since it is estimated that worldwide 5%-50% of OSA patients recommended for CPAP either reject or discontinue its use within the first week.¹¹⁰

5.0 FUTURE RESEARCH

Additional work is needed with respect to the following:

1. Further outcome studies comparing manual PAP titration studies vs. autotitrating PAP devices with respect to OSA severity and diverse patient populations.

2. Assessment of the reliability of selection of optimal pressure following PAP titration studies and the stability of the selected optimal pressure across successive PAP titration studies is needed.

3. Clinically significant thresholds for unintentional leak from the mouth or mask need to be identified.

4. Finally, advances in the technology for improving patient comfort and adherence to PAP devices are sorely needed.