Article info


Çekmen N.
Gökdemir B.N.


The Greek E-Journal of Perioperative Medicine 2023;22(b): 45-49




POSTED: 07/1/23 9:40 AM
ARCHIVED AS: 2023, 2023b, Case Reports

DOI: The Greek E-Journal of Perioperative Medicine 2023;22(b): 45-49

Authors: Gökdemir BN1*, Çekmen N2

1MD, Anesthesiology
2MD, PhD, Anesthesiology

Department of Anesthesiology, Faculty of Medicine, Baskent University, Ankara Turkey

*Correspondance: Department of Anesthesiology, Baskent University Faculty of Medicine, Hospital, Fevzi Cakmak Caddesi 10, Sokak No:45 Bahcelievler, 06490 Ankara, Turkey, Tel: 0312203 68 68- 4867, Email: .


Prader-Willi syndrome (PWS) is a rare genetic disorder characterized by various abnormalities, such as hypotonia, high body mass index (BMI), craniofacial anomalies, and obstructive sleep apnea. Anesthetic management of these patients requires special perioperative planning and care due to multisystem involvement. In this case report we present the anesthetic considerations and perioperative management of a 9-year-old male patient with PWS, who underwent adenoidectomy-tonsillectomy surgery.



Prader-Willi syndrome (PWS) is an uncommon genetic disorder that affects both males and females1. This syndrome was first described by Prader et al in 1956 and is caused by abnormalities on chromosome 15 (region 15q11-q13)2.The most characteristic manifestations of PWS are hypothalamic dysfunction, hypotonia, sucking and swallowing problems in infancy, hyperphagia in early childhood and also craniofacial anomalies, developmental delay, obstructive sleep apnea (OSA), mental retardation and behavioral problems or severe psychiatric problems3. Due to abnormalities of skeletal development and end-organ involvement, surgical procedures are often required in PWS patients. Scoliosis surgery, orchiopexy, adenotonsille-ctomy to treat OSA, ophthalmologic surgery in order to correct strabismus are surgical treatments that often undergo these patients4.

Anesthesiologists may face problems like difficult intravenous (IV) access, cardio-pulmonary complications, thermoregulator management issues, or difficult airway management5. Here, we presented the anesthe-tic management of a of a pediatric male patient with PWS, who underwent adenoidectomy- tonsillectomy surgery in order to treat OSA.


We present a case of a 9 years old male patient, with PWS syndrome scheduled for adenoide-ctomy – tonsillectomy surgery, for OSA treat-ment. His weight was 30 kg and his height 124cm. Patient had been diagnosed with PWS syndrome 4 years prior.

His medical record showed that he had OSA (apnea-hypopnea index=10) and for the last two years the patient used bilevel positive airway pressure (BPAP), for treating OSA. His growth was slower than the normal pattern and he was receiving growth hormones. No other medica-tion was administrated.

His preoperative physical examination was un-remarkable concerning respiratory or cardiac symptoms. Cardiac and pulmonary evaluations were performed preoperatively with no signify-cant findings. Physical exanination, also revea-led a large tongue relative to mouth, malocclu-sion and a large mandibula. The Mallampati score was obtained and evaluated as score III. Preoperative laboratory tests were within no-rmal values. He was cleared for surgery, assi-gned as ASA III physical status patient.

On arrival to the operating theater, standard monitoring was applied to the patient (heart ra-te, respiratory rate, non-invasive blood pressure, temperature, SpO2) and a heated blanked was also applied under the patient to prevent hypo-thermia.

Anesthesia was induced initially with sevoflu-rane inhalation and an intravenous (i.v) line was inserted. Atropine 0.01 mg/kg, fentanyl 2μg/kg, lidocaine 1 mg/k propofol 1mg/kg titrated to loss of consciousness and loss of eyelash reflex. Endotracheal intubation was facilitated with rocuronium bromide 0.6 mg /Kg. A 4 mm endotracheal tube was inserted uneventfully with the use of video laryngoscopy due to su-spected difficult airway. After intubation, the lungs were ventilated mechanically with FiO2 0.4 and for anesthesia maintenance sevoflurane and remifentanil 0.05-0.1 mcg/kg/min IV infu-sion were used. Ventilation was adjusted to keep PETCO2in the range 4.5-5.5 pKa. Intra-operatively patient’s hemodynamic parameters were stable.

After ten minutes of surgical time, a drop of SpO2 was noted (from 98% to 92%). Wide-spread wheezing was revealed on chest auscultation. Misplacement and occlusion of tracheal tube and breathing circuit were ruled out. With elevated airway pressure and up-slo-ping capnogram, bronchospasm was diagnosed. Instantaneously, FiO2 and sevoflurane was increased, propofol 2 mg/ kg was added, salbu-tamol puffs sprayed down tracheal tube and methylprednisolone 1mg/ kg was given. Ma-nual ventilation and recruitment maneuvers per-formed intraoperatively. Five minutes later, SpO2 gradually improved with the appearance of normal capnogram. After that incidence, sur-gical procedure proceeded uneventfully. Dura-tion of surgery was 80 minutes, without the ap-pearance of any hemodynamic or other complications.

Neuromuscular blockade reversal was achieved with the use of TOF (Train of four) monitoring and with the administration of sugammadex 2 mg/kg. Patient was extubated  in the operating room. He was alert, awake and able to follow commands. Postoperatively patient was trans-ferred to the post-anesthesia care unit (PACU) with normal vital signs. Later, he was dis-charged from PACU (Aldrete score 9) to the ward, without any coplications.


Prader-Willi’s syndrome (PWS) incidence is is about 1 in 15.000-25.000 births, and the male-to-female ratio is 3:26. It has been described as having two nutritional phases: inability to gain weight due to sucking and swallowing problems, in infancy (phase 1), hyperphagia leading to obesity, in early childhood (phase 2)3. Major features are muscular hypotonia, skeletal deformities, mental alterations and obesity3. Preventing obesity is directly related to life expectancy. Patients with PWS have also craniofacial abnormalities like narrow bifrontal diameter, upslanting palpebral fissures, thin upper lip, and triangular mouth7,8. Endocrine disorders like hypogonadism and diabetes mellitus accompany obesity. Due to growth hormone (GH) deficiency, short stature and decreased bone mineral density may occur9 Anesthetic management of these patients requires special perioperative planning and care due to multisystem involvement. Major concerns perioperatively include obesity and it’s related complications: cardiovascular disorders, obstructive sleep apnea, or diabetes mellitus10, and also muscular hypotonia, decreased motility of the gastrointestinal tract, lowered oesophageal sphincter tone, that may facilitate perioperative gastric aspiration in PWS patients.7 Nasogastric aspiration and rapid sequence induction during endotracheal intubation can prevent gastric aspiration11. Hypothalamic dysfunction can cause temperature disregulation, so monitoring temperature is necessary to maintain normothermia. Perioperative positioning and accessing IV lines may be challenging due to obesity12. General or regional anesthesia could be applied in PMS patients. Both types of anesthesia are challenging. General anaesthesia may lead mainly to difficult airway management and regional anaesthesia’s landmarks may be obscured due to morbid obesity. The appropriate equipment for difficult airway management should always be available in PWS patients. .

In our case, despite the fact that patient was not obese, broncospasm was diagnosed intraoperatively. We performed manual ventilation and recruitment maneuvers despite the possibility of atelectasis development14. Protective mechanical ventilation strategies were followed in order to protect the lungs from barotrauma14. Nafiu et al. showed that obese children were more likely to have complex ventilation problems and prolonged PACU stays, due to a high risk of postoperative airway obstruction 13. İt must be noted that PWS patients are prone to pulmonary complications and  restrictive lung diseases.


PWS is a genetic disorder that poses a significant challenge to anesthesiologists. Detailed physical examination and precision preparation are necessary in order to reduce morbidity and mortality. Early diagnosis of GH deficiency and its treatment has improved the quality of life of affected children. A multidisciplinary approach and comprehensive perioperative management may prevent complications.

Addittional materials: No

Acknowledgements: Not applicable

Author’s contributions: GBN drafted the paper and is the lead author. ÇN contributed to planning and the critical revision of the paper. All authors read and approved the fnal manuscript.

Funding: Not applicable.

Availability of supporting data:

Not applicable.

Ethical approval and consent to participate: No IRB approval required.

Consent for publication: Patient’s consent was obtained

Competing interests: Authors declare that they have no competing interests.

Received: February 2023, Accepted: April 2023, Published: June 2023.


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Citation Gökdemir BN, Çekmen N. Anesthetic Management of Prader Willi Syndrome patient undergoing tonsillectomy Surgery: A Case Report.Greek e j Perioper Med. 2023;22(b): 45-49.


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