Propofol is not effective for hyperventilation syndrome

Dexmedetomidine-treated hyperventilation syndrome triggered by the distress related with a urinary catheter after general anesthesia: a case report

Background

Hyperventilation syndrome (HVS) sometimes occurs in patients under stressful conditions and may provoke severe complications such as myocardial infarction and death. The authors report a case of HVS following general anesthesia, where a continuous intravenous infusion of dexmedetomidine was effective for HVS.

Case presentation

A 23-year-old male patient with recurrent tongue cancer was scheduled to undergo partial glossectomy and neck dissection. Emergence from general anesthesia was prompt. Twenty-two minutes after extubation, the patient complained of unbearable distress caused by the urinary catheter. He began to cry, with an increased respiratory rate of over 40 breaths per minute. Intravenous infusion of flurbiprofen, droperidol, and morphine was not effective. Electrocardiography and laryngofiberscopy indicated the absence of acute coronary syndrome and airway obstruction, respectively. An arterial blood gas determination showed pH 7.63, PaCO₂ 18.2 mmHg, PaO₂ 143 mmHg on O₂ mask 4 L/min, Ca²⁺ 4.29 mmol/L, and lactate 3.4 mmol/L. The patient was diagnosed with HVS. Dexmedetomidine infusion 2.0 μg/kg/h for 10 min followed by 0.7 μg/kg/h reduced respiratory rate, suppressed arousal, and disappeared the complaint of bladder distension. One hour after extubation, an arterial blood gas determination showed pH 7.33, PaCO₂ 51.3 mmHg, PaO₂ 196 mmHg on O₂ mask 4 L/min, Ca²⁺ 4.70 mmol/L, and lactate 1.5 mmol/L. After admission to the intensive care unit, dexmedetomidine infusion was maintained at the rate of 0.2 to 0.7 μg/kg/h until the following morning, and he did not complain of distress caused by the urinary catheter.

Conclusions

HVS can occur after emergence from general anesthesia, and dexmedetomidine infusion was effective for HVS.

Management of post-hyperventilation apnea during dental treatment under monitored anesthesia care with propofol

Although hyperventilation syndrome generally carries a good prognosis, it is associated with the risk of developing severe symptoms, such as post-hyperventilation apnea with hypoxemia and loss of consciousness. We experienced a patient who suffered from post-hyperventilation apnea. A 17-year-old female who suffered from hyperventilation syndrome for several years developed post-hyperventilation apnea after treatment using the paper bag rebreathing method and sedative administration during a dental procedure. We subsequently successfully provided her with monitored anesthesia care with propofol. Monitored anesthesia care with propofol may be effective for the general management of patients who have severe hyperventilation attacks and post-hyperventilation apnea. This case demonstrates that appropriate emergency treatment should be available for patients with hyperventilation attacks who are at risk of developing post-hyperventilation apnea associated with hypoxemia and loss of consciousness.

An acute postoperative intractable hyperventilation after an endoscopic third ventriculostomy

This report describes a rare case of postoperative hyperventilation attack after an endoscopic third ventriculostomy in a 46-year-old woman. About 60 min after the termination of the operation, an intractable hyperventilation started with respiratory rate of 65 breaths/min and EtCO₂, 16.3 mm Hg. Sedation with benzodiazepine, thiopental sodium, fentanyl, and propofol/remifentanil infusion was tried under a rebreathing mask at a 4 L/min of oxygen. With aggressive sedative challenges, ventilation pattern was gradually returned to normal during the 22 hrs of time after the surgery. A central neurogenic hyperventilation was suspected due to the stimulating central respiratory center by cold acidic irrigation solution during the neuroendoscopic procedure.