Atypical involuntary movements following fentanyl anesthesia

Postanesthetic involuntary movements are triggered by a variety of drugs, including propofol, sevoflurane, anti-emetics, and anti-psychotics. A case of acute involuntary movements in a healthy man after fentanyl exposure is presented. The movements consisted of large-amplitude motions of the upper limbs of the elbow joint for flexion and extension, and shaking of the head from side to side.     

Biphasic respiratory depression after fentanyldroperidol or fentanyl alone used to supplement nitrous oxide anesthesia.

Either fentanyl or Innovar (fentanyl, 0.05 mg/ml, and droperidol 2.5 mg/ml) was administered to supplement nitrous oxide anesthesia for operations on 29 patients. Both fentanyl and Innovar depressed the slope of the rebreathing CO2 response curve during operation to 42 per cent +/- 6 (mean of all intraoperative values, +/- SE) of the awake control value. Following the last injection of drug but with continuation of operation, the slope increased such that it was 77 per cent +/- 8 of control on the patients' arrival in the recovery room. The slope continued to increase to a peak of 103 per cent +/- 9 of control. Soon therafter respiratory depression recurred, as indicated by a decline in the slope to 55 per cent +/- 5 of control, with a subsequent gradual return to 85 per cent +/- 8 of control 230 minutes after the last injection. This biphasic response occurred in 90 per cent (26 of 29) of the patients treated either with fentanyl alone or with Innovar. Full recovery appeared to be more rapid with Innovar than with fentanyl alone. Droperidol did not augment and may have attenuated fentanyl-induced respiratory-depression.     

Delayed respiratory depression after risperidone overdose

Risperidone is an atypical antipsychotic drug used for the treatment of schizophrenia. Both positive and negative symptoms are prominent with its use. Metabolism occurs mainly in the liver, where risperidone is changed by CUP2D6 to an active metabolite, 9-hydroxyrisperidone. The half-lives of risperidone and its metabolite are 3 and 7 h, respectively. Genetic polymorphism is seen in the 6%-8% of white patients who are considered poor metabolizers. In poor metabolizers, the half-life extends to 20-30 h. We present an unusual case of unanticipated delayed respiratory depression after risperidone overdose.     

Prolonged respiratory depression following general anesthesia in a patient with dystrophia myotonica

A case of general anesthesia for a 52 year old female with previously undiagnosed dystrophia myotonica was reported. The patient was diagnosed as flaccid paralysis of the bilateral lower extremities but myotonic symptoms were not found preoperatively. The patient underwent duodenal resection to have a benign tumor removed. Anesthesia was induced with thiamylal 250 mg and pancuronium bromide 4 mg intravenously to facilitate tracheal intubation. Anesthesia was maintained with enflurane (0.6-1.0%) in nitrous oxide (50%) and oxygen (50%). The course of anesthesia was uneventful except for a transient hypotension of 80 mmHg systolic for about 10 minutes. The patient did not recover smoothly from anesthesia and prolonged apnea was observed. 90 minutes after the end of surgical procedure, spontaneous ventilation appeared. Then the tidal volume increased gradually but it still remained around 100-150 ml even 3 hours after the end of the operation. She was on ventilator and observed carefully. The endotracheal tube was removed four days after the operation. The patient was examined again by a neurologist and a final diagnosis of dystrophia myotonica was made. Prolonged recovery from anesthesia and postoperative respiratory depression observed in this patient was due to preoperatively undiagnosed dystrophia myotonica. A careful preoperative examination should be made to minimize possible complication related to anesthesia in the disease.     

妊娠可以减弱芬太尼对呼吸的抑制

目的观察妊娠对静注芬太尼引起的呼吸抑制的影响。方法随机选择年龄20～35岁女性,未孕拟行腹腔镜手术治疗患者(对照组)、妊娠45～60d拟行无痛人流手术患者(孕早期组)和自然分娩后5～7d内拟无痛清宫患者(产后组),每组20例。以1ml/3s的速度静注芬太尼2μg/kg,观察患者给药前后RR、PETCO2和SpO2的变化,同时检测患者的孕酮值。结果给药后3min孕早期组和产后组患者RR均显著快于对照组(P<0.05);给药后6、9和12min孕早期组和产后组SpO2均显著高于对照组(P<0.05);给药后9、12和15min孕早期组和产后组PETCO2均显著低于对照组(P<0.05)。患者注射芬太尼后最低SpO2与其孕酮值明显相关(P<0.01)。结论妊娠减轻静注芬太尼引起的呼吸抑制,其作用可能与孕酮有关。     

Reversal by nalbuphine of respiratory depression caused by fentanyl

In 60 ASA class I or II patients given intravenous fentanyl for elective operations in doses large enough to produce postoperative respiratory depression, the intravenous administration of 20 mg nalbuphine resulted in prompt reversal of respiratory depression without loss of analgesia.     

Buprenorphine antagonism of ventilatory depression following fentanyl anaesthesia

In order to compare the effect of buprenorphine and naloxone on respiratory depression after fentanyl anaesthesia (25 micrograms/kg), 32 women scheduled for elective abdominal hysterectomy participated in a double-blind randomized investigation. At termination of anaesthesia, after antagonizing residual neuromuscular blockade, 20 normocapnic patients with a respiratory rate of 4 breaths/min or less entered the study, receiving either buprenorphine (0.6 mg in 20 ml NaCl) or naloxone (0.4 mg in 20 ml NaCl) 2 ml/min until 20 ml was given or until the respiratory rate exceeded 8 breaths/min. Respiratory rate, PaCO2, sedation score, and pain intensity were evaluated during a 3-h study period. Fifteen min after beginning the treatment, all the patients in both groups had their ventilatory depression antagonized. There were no statistically significant differences in respiratory rates between groups except at 15 min. On no occasion did either PaCO2 or a sedation score differ statistically significantly between the groups. At 15 min all patients in the buprenorphine group had no or mild pain, compared to the patients in the naloxone group, of whom 50% had moderate to severe pain (P less than 0.05). It seems as if buprenorphine is as effective as naloxone in antagonizing respiratory rate depression following fentanyl anaesthesia.     

Post-operative rigidity after fentanyl administration

A case of thoraco-abdominal rigidity leading to respiratory failure is described in the post-operative period in an elderly patient who received a moderate dose of fentanyl. This was successfully reversed by naloxone. The mechanisms possibly implicated in this accident are discussed.     

Delayed profound respiratory depression after premedication with trimeprazine

Delayed, profound respiratory depression occurred in a 4-year-old boy, who had been premedicated with trimeprazine 4 h after tonsillectomy. This is a rare, but potentially fatal idiosyncratic reaction.     

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.     

Comparison of nalbuphine and fentanyl anesthesia for coronary artery bypass surgery. Hemodynamics, hormonal response, and postoperative respiratory depression

To determine whether nalbuphine might replace fentanyl as the principal opioid for anesthesia during coronary artery bypass surgery, 20 patients undergoing myocardial revascularization were anesthetized with flunitrazepam and with a continuous infusion of either nalbuphine (an opioid agonist-antagonist) or fentanyl (a pure opioid agonist) in equipotent dosage ratio of 333:1. During endotracheal intubation, all patients given nalbuphine, but only one given fentanyl (P less than 0.05), required nitroglycerin to control arterial blood pressure. Two minutes after tracheal intubation, plasma values of epinephrine, norepinephrine, vasopressin, and cortisol did not change in the fentanyl group compared with the awake (baseline) levels, whereas catecholamines and vasopressin significantly increased with nalbuphine compared with the baseline and with the values in the fentanyl group. A steady state of anesthesia (30 min after intubation), when compared with the baseline, was characterized by unchanged systemic and pulmonary blood pressures and increased systemic vascular resistance with nalbuphine, by decreased systemic and pulmonary pressures and resistances with fentanyl, and by comparably decreased cardiac index with both opioids. Hormone values returned to baseline levels but norepinephrine remained significantly higher in the nalbuphine than in the fentanyl group. A bolus injection of either nalbuphine (2.5 mg/kg) or fentanyl (7.5 micrograms/kg) given during the steady-state period of anesthesia provoked only minimal hemodynamic changes. Before skin incision, 7 of 10 patients receiving nalbuphine required nitroglycerin to control arterial blood pressure. After sternotomy, both groups required nitroglycerin, but additional antihypertensive drugs were necessary mainly in the nalbuphine group.(ABSTRACT TRUNCATED AT 250 WORDS)