Opisthotonos following propofol: a nonepileptic perspective and treatment strategy

Anesthetic nuances in Segawa's syndrome: A case report and review of the literature

Segawa's syndrome, dopamine-responsive dystonia, is a rare genetic disorder that typically begins in childhood by around 4–6 years of age. It is characterized by abnormal gait and dystonia. A 33-year-old man presented for autologous skin grafting of a nonhealing wound under general anesthesia. Successful anesthetic management of patients with this rare disease, though analogous in many ways to that of patients with Parkinson's disease, still pose significant challenges. We present anesthetic nuances to be considered in the management of a patient with Segawa's disease along with a pertinent review of the literature.

Severe Neuroexcitatory Reaction: A Rare and Underrecognized Life-Threatening Complication of Propofol-Induced Anesthesia

We describe a case of severe neuroexcitatory reaction with hyperthermia after administration of propofol in a 43-year-old patient suspected of a relapse of sarcoidosis who underwent bronchoscopy. This resulted in a lengthy stay in intensive care and long-term neuropsychological impairment. A review of the literature shows that severe neuroexcitatory symptoms (seizure-like phenomena, abnormal hypertonic, and/or jerky movements) occur rarely after propofol administration and may be life-threatening. Due to the paucity of data, the treatment is mostly empirical. The diagnosis can also be delayed owing to underrecognition. We conclude that health practitioners who frequently use propofol should be aware of this specific manifestation of drug toxicity, which albeit rare can be devastating for the patient.

Diphenhydramine for Acute Extrapyramidal Symptoms After Propofol Administration

Extrapyramidal symptoms are an uncommon but well-recognized side effect after the administration of general anesthesia in patients without a significant neurologic history. Several case reports implicate propofol as the likely causative agent producing these symptoms, which include ballismus, dystonia, choreoathetosis, and opisthotonus. Currently, there is no clear consensus on first-line treatment of these symptoms. In each of the published cases, anticholinergic medications and benzodiazepines were central to initial management, although the speed and extent of symptom resolution were variable. Here we present a case of a 17-year-old boy with ulcerative colitis who presented with ballismus, torticollis, tongue thrusting, and oculogyric movements after colonoscopy under general anesthesia with propofol. The patient responded promptly to treatment with diphenhydramine. This is the first reported case in which diphenhydramine was successfully used as the primary treatment of severe extrapyramidal symptoms in a pediatric patient after propofol administration.

Anesthetic considerations in scoliosis patient with dopa-responsive dystonia or Segawa's syndrome

Segawa's syndrome or dopa-responsive dystonia is a rare hereditary disorder characterized by progressive dystonia of childhood onset, diurnal fluctuation of symptoms and complete or near complete alleviation of symptoms with administration of low-dose oral levodopa. From our literature search in PubMed, we found only three related publications: two on anesthesia for cesarean section and one on anesthesia for electroconvulsive therapy. We report our experience in providing anesthesia for corrective scoliosis surgery in two biological sisters with Segawa's syndrome. A review of the literature is also included.

Delayed onset refractory dystonic movements following propofol anesthesia

Neuroexcitation is an uncommon but well recognized side effect of propofol anesthesia and sedation. We present a patient who, despite an intact mental status and without any preexisting movement disorder, experienced delayed onset of involuntary dystonic movements involving head, neck and shoulder for 11 h following emergence from propofol/nitrous oxide anesthesia.

Propofol treatment of refractory status epilepticus: a study of 31 episodes

PURPOSE

Refractory status epilepticus (RSE) is a critical medical condition with high mortality. Although propofol (PRO) is considered an alternative treatment to barbiturates for the management of RSE, only limited data are available. The aim of this study was to assess PRO effectiveness in patients with RSE.

METHODS

We retrospectively considered all consecutive patients with RSE admitted to the medical intensive care unit (ICU) between 1997 and 2002 treated with PRO for induction of EEG-monitored burst suppression. Subjects with anoxic encephalopathy showing pathological N20 on somatosensory evoked potentials were excluded.

RESULTS

We studied 31 RSE episodes in 27 adults (16 men, 11 women; median age, 41.5 years). All patients received PRO, and six also subsequently thiopental (THP). Clonazepam (CZP) was administered with PRO, and other antiepileptic drugs (AEDs) concomitant with PRO and THP. RSE was successfully treated with PRO in 21 (67%) episodes and with THP after PRO in three (10%). Median PRO injection rate was 4.8 mg/kg/h (range, 2.1-13), median duration of PRO treatment was 3 days (range, 1-9), and median duration of ICU stay was 7 days (range, 2-42). In 24 episodes in which the patient survived, shivering after general anesthesia was seen in 10 episodes, transient dystonia and hyperlipemia in one each, and mild neuropsychological impairment in five. The seven deaths were not directly related to PRO use.

CONCLUSIONS

PRO administered with CZP was effective in controlling most of RSE episodes, without major adverse effects. In this setting, PRO may therefore represent a valuable alternative to barbiturates. A randomized trial with these drug classes could definitively assess their respective role in RSE treatment.

Fentanyl-induced rigidity during emergence from general anesthesia potentiated by venlafexine

PURPOSE

To present and discuss a case of opioid-induced rigidity with low-dose fentanyl during recovery from anesthesia.

CLINICAL FEATURES

A 41-yr-old woman underwent laparotomy for total abdominal hysterectomy and bilateral salpingo- oophorectomy under general anesthesia. She received a total of 500 micro g of fentanyl by iv intermittent boluses during the three-hour anesthetic. During emergence from anesthesia, while intubated, the patient presented with rigidity. No changes in ventilatory parameters were measured during the episode. The only notable predisposing factor was treatment with venlafexine, an antidepressant that modifies serotonin and norepinephrine levels. She was successfully treated with iv naloxone 20 micro g. The rest of the postoperative period was uneventful.

CONCLUSION

We observed an atypical case of opioid-induced rigidity in contrast to the classical syndrome, which presents at induction with high-dose opioids. This syndrome has many clinical presentations with neurologic and ventilatory signs of varying intensity. Early recognition of the syndrome and adequate treatment is crucial. If treated adequately, opioid-induced rigidity is self-limited with few complications.

Dystonic reaction to propofol attenuated by benztropine (cogentin)

IMPLICATIONS

Neuroexcitatory movements associated with propofol anesthesia are well recognized. Here we report on the successful use of benztropine (2 mg) to abolish abnormal dystonic movements after propofol anesthesia. Forty-five case reports are reviewed, and a treatment strategy for abnormal movements during propofol anesthesia is provided.

Use of propofol to manage seizure activity after surgical treatment of portosystemic shunts

The anaesthetic agent propofol has anticonvulsant properties and has been used in the treatment of refractory status epilepticus in human medicine. This report describes the use of propofol in four cats and one dog with naturally occurring seizures following surgical attenuation of single extrahepatic portosystemic shunts. Two of the animals had seizures that were unresponsive to other anticonvulsants. Subanaesthetic doses of intravenous propofol (1.0 to 3.5 mg/kg boluses and 0.01 to 0.25 mg/kg/minute continuous rate infusions) were used to control the seizures in all animals. However, a good neurological outcome was achieved in only two of the five cases, which is similar to the situation in previous reports.

Rats show unimpaired learning within minutes after recovery from single bolus propofol anesthesia

PURPOSE

To examine the learning ability of rats shortly after recovery from a bolus dose of propofol by assessing learning on a swim-to-platform task. Also, muscarinic blockade was used as a pharmacological test of whether learning shortly after propofol anesthesia resembles normal learning.

METHODS

Propofol anesthetized rats (15-20 mg x kg(-1) i.v.) were trained on a swim-to-platform task five to seven minutes after recovering from surgical anesthesia and tested two to three hours later In addition, the muscarinic antagonist scopolamine hydrobromide (5 mg x kg(-1) s.c.) was given to a subgroup of rats before testing. During 10 trials, the number of times a given rat took 10 sec or longer to locate and climb onto a visible platform was tabulated and counted as errors.

RESULTS

When trained shortly after recovery from the anesthetic, propofol anesthetized rats made 3.2 +/- 0.4 compared with 1.0 +/- 0.1 errors in controls (P < 0.0001). Two to three hours later both groups performed equally well. Rats trained after propofol anesthesia and given scopolamine before testing made 0.7 +/- 0.5 errors and performed as well as normal controls, 1.2 +/- 0.2 errors when subjected to the same procedures without propofol anesthesia, and better than scopolamine-treated untrained rats, 5.5 +/- 0.7 errors, (P < 0.05).

CONCLUSION

Training five to seven minutes after recovery from propofol anesthesia resulted in normal retention of the swim- to-platform task. It also produced the same resistance to the disruptive effects of scopolamine as did training in rats that were not anesthetized. Thus, the ability to learn recovers rapidly after propofol anesthesia induced by a single intravenous bolus dose.

Propofol sedation produces dose-dependent suppression of lidocaine-induced seizures in rats

The association of propofol with excitatory motor activity, such as myoclonic jerking and opisthotonus, in humans and in animals suggests that it may aggravate clinical seizure activity in some circumstances, although evidence suggests that under other circumstances, propofol inhibits seizure activity. In the current study, we assessed the effect of sedating doses of propofol on lidocaine-induced seizure activity in spontaneously breathing rats receiving no other anesthetics. Adult Sprague-Dawley male rats, 300-400 g, were divided into a control group and three experimental groups representing three graded levels of propofol sedation. The control rats then received a lidocaine infusion at the rate of 150 mg x kg(-1) x h(-1), resulting in a slow, progressive increase in systemic lidocaine concentrations. At the onset of electroencephalographic (EEG) seizure activity, arterial lidocaine concentrations were obtained. The treated rats received propofol according to three different dose schedules: Dose 1 = 10 mg x kg(-1) x h(-1) after a 2.5-mg/kg bolus; Dose 2 = 20 mg x kg(-1) x h(-1) after a 5-mg/kg bolus; Dose 3 = 40 mg x kg(-1) x h(-1) after a 10-mg/kg bolus. After 30 min, a steady level of sedation, dependent on the dose of propofol, was achieved. The lidocaine infusion was then started, and systemic lidocaine levels were obtained at the onset of EEG seizure activity. The lidocaine was continued until the onset of death by cardiac arrest. Plasma lidocaine was measured by gas chromatography. Analysis of variance and Dunnett's t-test were used for comparisons with the control values. Continuous propofol sedation increased the seizure dose of lidocaine from 37.7 +/- 3.5 mg/kg (mean +/- SEM) to 52.5 +/- 2.6 mg/kg (Dose 1, P < 0.05) and 67.9 +/- 8.6 mg/kg (Dose 2, P < 0.05), and completely abolished lidocaine seizures at Dose 3. The lethal dose of lidocaine, 89.4 +/- 10.5 mg/kg control versus 108.7 +/- 10.3 mg/kg (Dose 1), 98.3 +/- 10.1 mg/kg (Dose 2), and 93.5 +/- 10.4 mg/kg (Dose 3) did not differ among groups. The lidocaine levels at seizure threshold were increased in the propofol-treated rats: 16.9 +/- 0.5 microg/mL control versus 19.2 +/- 0.7 microg/mL (Dose 1, P = not significant) and 23.7 +/- 1.8 microg/mL (Dose 2, P < 0.05). Continuous propofol sedation in spontaneously breathing rats receiving no other anesthetics exerts a protective effect against lidocaine-induced seizures in a monotonic, dose-dependent fashion. The cardiac arrest dose of lidocaine is unaffected by propofol under these conditions.

IMPLICATIONS

The i.v. anesthetic drug propofol, given to rats to produce sedation, was found to suppress seizure activity caused by overdosage of the local anesthetic lidocaine.

Propofol for sedation in the intensive care unit: essentials for the clinician

Propofol is a short-acting intravenous anesthetic commonly utilised in the intensive care unit (ICU) for sedation of mechanically ventilated patients. The rapid onset and termination of action make it an attractive drug for use in the ICU. The safety profile of propofol is well established. However, there are potential adverse reactions associated with the drug. This review discusses the pharmacology, administration and adverse effects associated with propofol with which clinicians who administer propofol should be familiar.

Midazolam premedication delays recovery after propofol without modifying involuntary movements

Midazolam has GABAergic effects in children that may modify propofol-induced involuntary movements, yet delay recovery. In a double-blind, randomized study, 24 children (2-7 yr of age, ASA physical status I or II) undergoing short surgical procedures received midazolam 0.5 mg/kg (Group M) or placebo (Group P) per os 20-30 min before propofol anesthesia (5 mg/kg intravenously followed by an infusion). Blind observers scored sedation and anxiety levels (scale 1-4) before premedication, at separation from parents, and at induction of anesthesia. Induction and emergence were videotaped, and body movements were recorded. During recovery, times to eye opening and maximum Steward (SS = 6) and Vancouver Sedative Recovery (VSRS = 22) scores were noted. Parents were questioned about side effects that may have occurred during the following week. Both groups were similar in age, sex, weight, timing of premedication, propofol dose, and duration of surgery. The incidence of involuntary movements did not differ between groups but was higher at induction (79%) than on emergence (25%) (P < 0.05). Anxiety and sedation scores were similar in Group P and Group M, but recovery took longer after midazolam, with eye opening (mean +/- SD) 24 +/- 7 vs 43 +/- 18 min, maximum SS (median and range) 27 (13-37) vs 55 (24-138) min, and maximum VSRS 51 (30-100) vs 80 (50-130) min. Children returned to normal activity in 1 (0-5) day, and none exhibited neurological complications. We conclude that an oral premedicant dose of midazolam prolongs recovery from anesthesia in children without affecting dystonic movements after propofol.

Refractory dystonia during propofol anaesthesia in a patient with torticollis-dystonia disorder

PURPOSE

To report a case of refractory dystonia under propofol anaesthesia in a patient with Torticollis-Dystonia disorder.

CLINICAL FEATURES

A 38-yr-old man presented for an MRI scan for investigation of a Torticollis-Dystonia disorder. There was a biphasic response to propofol with complete amelioration of the torticollis and limb dystonia initially with subsequent recurrence under deep propofol anaesthesia. Coadministration of midazolam, diazepam, and thiopentone were not successful in abolishing the recurrent dystonia.

CONCLUSIONS

Propofol should preferably be avoided in patients with torticollis and dystonias. Where complete control of movements is required, it may be necessary to consider general endotracheal anaesthesia with muscle relaxants.

Large-dose propofol alone in adult epileptic patients: electrocorticographic results

The primary objective of this study was to evaluate the electrophysiologic effects of large-dose propofol, used as the sole anesthetic in patients with epilepsy. Nine patients with medically intractable complex partial epilepsy undergoing a three-stage approach to the surgical management of epilepsy were recruited. State I involved placement of the intracranial electrode array, while Stage II consisted of extraoperative localization of the seizure focus. The patients were studied during induction of anesthesia for Stage III (removal of electrodes and resection of seizure focus). Unpremedicated patients were induced with a propofol infusion (0.5 mg.kg-1.min-1) until one of the following occurred: 1) electrical seizure activity, 2) burst suppression, or 3) total dose of 10 mg/mg. Electrocorticography (ECoG) was recorded continuously during this period. Two patients were excluded from the study after experiencing delayed awakening after the Stage I procedure. Both had received propofol along with other anesthetics. No ECoG evidence of seizure activity was detected in the seven patients completing the study. Burst suppression was attained in six patients using a mean dose of 5.7 mg/kg +/- 2.6. We conclude that large dose propofol alone does not trigger electrical epileptiform activity on the ECoG of seizure patients.

Propofol in prehospital treatment of convulsive status epilepticus

We studied the safety and efficacy of intravenous propofol in the out-of-hospital treatment of convulsive status epilepticus (SE) in 8 patients (age 29-70 years), 4 of them with posttraumatic epilepsy. Four patients had no history of seizures. Convulsions ceased promptly after patients received a bolus of 100-200 mg propofol administered before hospital admission by staff of a mobile intensive care unit (ICU). The median duration of coma was 3 h 15 min (range 2-41 h), and the median duration of hospital treatment was 3 1/2 days (range 12 h to 23 days). Only 1 patient was admitted to the hospital's ICU. No adverse effects was observed except for a transient decrease in systolic blood pressure (SBP). Propofol may be a useful drug for the prehospital treatment of recurrent seizures not responding to intravenous diazepam (DZP).

Propofol. An overview of its pharmacology and a review of its clinical efficacy in intensive care sedation

Propofol is a phenolic derivative that is structurally unrelated to other sedative hypnotic agents. It has been used extensively as an anaesthetic agent, particularly in procedures of short duration. More recently it has been investigated as a sedative in the intensive care unit (ICU) where it produces sedation and hypnosis in a dose-dependent manner. Propofol also provides control of stress responses and has anticonvulsant and amnesic properties. Importantly, its pharmacokinetic properties are characterised by a rapid onset and short duration of action. Noncomparative and comparative trials have evaluated the use of propofol for the sedation of mechanically ventilated patients in the ICU (postsurgical, general medical, trauma). Overall, propofol provides satisfactory sedation and is associated with good haemodynamic stability. It produces results similar to or better than those seen with midazolam or other comparator agents when the quality of sedation and/or the amount of time that patients were at adequate levels of sedation are measured. Patients sedated with propofol also tend to have a faster recovery (time to spontaneous ventilation or extubation) than patients sedated with midazolam. Although most studies did not measure time to discharge from the ICU, propofol tended to be superior to midazolam in this respect. In a few small trials in patients with head trauma or following neurosurgery, propofol was associated with adequate sedation and control of cerebral haemodynamics. The rapid recovery of patients after stopping propofol makes it an attractive option in the ICU, particularly for patients requiring only short term sedation. In short term sedation, propofol, despite its generally higher acquisition costs, has the potential to reduce overall medical costs if patients are able to be extubated and discharged from the ICU sooner. Because of the potential for hyperlipidaemia and the development of tolerance to its sedative effects, and because of the reduced need for rapid reversal of drug effects in long term sedation, the usefulness of propofol in long term situations is less well established. While experience with propofol for the sedation of patients in the ICU is extensive, there are still areas requiring further investigation. These include studies in children, trials examining cerebral and haemodynamic outcomes following long term administration and in patients with head trauma and, importantly, pharmacoeconomic investigations to determine those situations where propofol is cost effective. In the meantime, propofol is a well established treatment native to benzodiazepines and/or other hypnotics or analgesics when sedation of patients in the ICU is required. In particular, propofol possesses unique advantages over these agents in patients requiring only short term sedation.

Sudden unexpected sneezing during the insertion of peribulbar block under propofol sedation

The author presents a case report where, following propofol sedation for a peribulbar block, sneezing was induced once the local anaesthetic needle was placed in the orbital cavity. The physiology of sneezing is discussed, as well as the pathophysiology of the ACHOO (Autosomal Dominant Compelling Helio-Ophthalmic Outburst) syndrome, an autosomal dominant condition, present in approximately 25% of the population, where sneezing is provoked upon exposure to bright light. It is suggested that the anaesthesia induced by propofol may have sensitized patients with this condition to sneeze, since there appeared to be no other excitatory sequelae which have previously been described with propofol.

Prolonged myoclonus and meningism following propofol

The purpose of this report is to describe a new complication of propofol administration. A previously fit patient underwent intravenous anaesthesia with propofol for removal of dental wires. Postoperatively he developed myoclonic jerking of his limbs. On regaining consciousness he complained of an occipital headache, neck stiffness and photophobia, and was found to have nuchal rigidity on examination. These clinical features resolved over the following week. Subsequent investigations failed to explain the aetiology of the symptoms of meningeal irritation, which suggests that propofol was the causative agent. While prolonged myoclonus has been previously described with propofol administration, this is the first report of meningism occurring with its use.