CHIRURGIE BARIATRIQUE : DÉPISTAGE DE L`HTP CHEZ LE SAOS

CHIRURGIE BARIATRIQUE :

DÉPISTAGE DE L’HTP CHEZ LE SAOS

DONAT Alexis Hôpital Antoine Béclère

Obésité et SAOS?

cardiovascular disease accelerates disease progression, and

whether treatment of sleep apnea results in clinical im-

provement, fewer cardiovascular events, and reduced

mortality.

Experimental approaches directed at addressing these issues

are limited by several considerations. First, the close association

between obesity and OSA often obscures differentiation be-

tween the effects of obesity, the effects of OSA, and the effects

of synergies between these conditions. Second, multiple comor-

bidities, including cardiovascular disease, metabolic syndrome,

and diabetes, often are present in patients with sleep apnea.

Hence, it becomes unclear whether abnormalities evident in the

sleep apnea patient with cardiovascular disease are secondary to

the sleep apnea, the cardiovascular condition, or both. The third

consideration relates to randomization of sleep apnea patients to

active or no treatment. Although this is a reasonable strategy for

identifying the mechanistic and prognostic consequences of

sleep apnea per se, it is limited by the difficulties inherent in any

placebo-controlled treatment study of sleep apnea and the need

to consider treatment in patients with severe daytime somno-

lence, even in the absence of associated cardiovascular disease.

Definitions, Classifications, Diagnosis,

and Pathophysiology

Obstructive Sleep Apnea

OSA is characterized by repetitive interruption of ventilation

during sleep caused by collapse of the pharyngeal airway. An

obstructive apnea is a !10-second pause in respiration

associated with ongoing ventilatory effort. Obstructive hy-

popneas are decreases in, but not complete cessation of,

ventilation, with an associated fall in oxygen saturation or

arousal. A diagnosis of OSA syndrome is accepted when a

patient has an apnea-hypopnea index (AHI; number of apneas

and hypopneas per hour of sleep) !5 and symptoms of

excessive daytime sleepiness

20

(Figure 1 and Table 1; see

Table 2

5

for definitions of terms).

Although hypopneas constitute the majority of disordered

breathing events, there is some controversy regarding the

optimal criteria for definition of hypopneas. A recent analysis

of data from !6000 adults participating in the Sleep Heart

Health Study noted that hypopneas accompanied by oxyhe-

moglobin desaturation of !4% were associated with preva-

lent cardiovascular disease independently of confounding

covariates.

21

In contrast, no association was observed be-

Figure 1. Partial and complete airway

obstruction resulting in hypopnea and

apnea, respectively. Reprinted from Hahn

PY, Somers VK. Sleep apnea and hyperten-

sion. In: Lip GYH, Hall JE, eds. Comprehen-

sive Hypertension. St. Louis, Mo: Mosby;

2007:201–207. Copyright Elsevier 2007.

Used with permission.

Table 1. Obstructive Sleep Apnea

Signs, symptoms, and risk factors

Disruptive snoring

Witnessed apnea or gasping

Obesity and/or enlarged neck size

Hypersomnolence (not common in children or in heart failure)

Other signs and symptoms include male gender, crowded-appearing

pharyngeal airway, increased blood pressure, morning headache, sexual

dysfunction, behavioral changes (especially in children)

Screening and diagnostic tests

Questionnaires

Holter monitoring

Overnight oximetry

Home-based/ambulatory unattended polysomnography

In-hospital attended overnight polysomnography

Treatment options

Positional therapy

Weight loss

Avoidance of alcohol and sedatives

Positive airway pressure

Oral appliances

Surgery

Uvulopalatopharyngoplasty

Tonsillectomy

Tracheostomy

Somers et al AHA/ACCF Sleep Apnea and Cardiovascular Disease 1081

by guest on December 18, 2015http://circ.ahajournals.org/Downloaded from

Syndrome d’apnée obstructive du sommeil

! Fréquent : 70 % des patients de chirurgie bariatrique

! Mécanisme : interruption répétitive de la ventilation

! durant le sommeil

! par collapsus pharyngé