Postoperative Hypoxemia in Morbidly Obese Patients With and Without Obstructive Sleep Apnea Undergoing Laparoscopic Bariatric Surgery

Department of Anesthesiology, Northwestern University Feinberg School of Medicine, 251 E. Huron St., F5-704 Chicago, IL 0 60611, USA.
Anesthesia and analgesia (Impact Factor: 3.47). 07/2008; 107(1):138-43. DOI: 10.1213/ane.0b013e318174df8b
Source: PubMed


The increased incidence of morbid obesity has resulted in an increase of bariatric surgical procedures. Obstructive sleep apnea (OSA) is a commonly encountered comorbidity in morbidly obese patients. Sedatives, analgesics, and anesthetics alter airway tone, and airway obstruction and death have been reported in patients with OSA after minimal doses of sedatives and anesthetics, yet there is a lack of consensus regarding the care of these patients. In this study, we sought to determine whether obese patients with polysomnography-confirmed diagnosis of OSA were at significantly greater risk for postoperative hypoxemic episodes in the first 24 h after laparoscopic bariatric surgery than morbidly obese patients without a diagnosis of OSA.
Adult subjects (Body Mass Index, 35-75 kg/m(2)) scheduled to undergo laparoscopic bariatric surgery were studied. A finger pulse oximetry probe was placed preoperatively and oxygen saturation (Spo(2)) was recorded continuously. All subjects underwent preoperative polysomnography testing within 4 wk of surgery. Anesthetic management was standardized, using propofol for induction and desflurane and remifentanil for maintenance of anesthesia. Patient-controlled analgesia programmed to deliver morphine, 1 mg. every 10 minutes, was used for pain management postoperatively. Hypoxemic episodes were scored as Spo(2) >4% below the polysomnography study baseline and lasting for more than 10 s.
Eight men and 32 women were enrolled and 1 subject had incomplete data. Thirty-one of the 40 subjects had polysomnography-confirmed OSA. Eight subjects used home continuous positive airway pressure devices nightly, and six of these used their device postoperatively. Preoperatively, subjects with OSA had lower nadir Spo(2) during the polysomnography study and a larger number had an apnea/hypopnea index >10 episodes per hour compared with the non-OSA group. In the first 24 h postoperatively, there was no difference in the median Spo(2) with and without oxygen therapy, between OSA and non-OSA groups. The number of episodes of oxygen desaturation >4% below the polysomnography study baseline value and the mean number of desaturation episodes per hour did not differ between the groups.
In morbidly obese subjects, in the first 24 h after laparoscopic bariatric surgery, OSA does not seem to increase the risk of postoperative hypoxemia. Our data confirm that morbidly obese subjects, with or without OSA, experience frequent oxygen desaturation episodes postoperatively, despite supplemental oxygen therapy suggesting that perioperative management strategies in morbidly obese patients undergoing laparoscopic bariatric surgery should include measures to prevent postoperative hypoxemia.

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    • "TAP blocks have been implemented successfully for pain control after laparoscopic surgery in nonobese patients undergoing diverse procedures ranging from appendectomy to neurostimulator implants.4–11 The resulting analgesia may be especially beneficial in morbidly obese patients after abdominal surgery due to their higher risk for postoperative pulmonary complication.12,13 The introduction of ultrasound guidance has allowed greater precision of needle placement in the desired tissue plane.14 "
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    • "Similarly, sleep-disordered breathing was listed as a likely contributor to all opioid-related deaths mainly based on an expert panel's opinion (Webster et al., 2011). In contrast, a few recent reviews and reports have questioned whether OSA is an independent risk factor for perioperative adverse events (Sabers et al., 2003; Ahmad et al., 2008; Ankichetty et al., 2011; Macintyre et al., 2011; Weingarten et al., 2011). These reviews suggest that these adverse events may be related to co-existing obesity (Weingarten et al., 2011). "
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    Respiratory Physiology & Neurobiology 11/2012; 185(3). DOI:10.1016/j.resp.2012.11.014 · 1.97 Impact Factor
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    • "Decreased oxygen saturation (P < 0.05) was described in the immediate postoperative period when propofol was administered with isoflurane.[2930] However, no difference in oxygen desaturation index between OSA and non-OSA groups was noted in a randomized prospective study with propofol, desflurane, and remifentanil.[28] With the administration of propofol alone for sedation, no adverse respiratory effects were reported.[31] "
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