Transnasal butorphanol is effective for postoperative pain relief in children undergoing myringotomy.

BACKGROUND: More than 70% of children require analgesics after bilateral myringotomy and tube placement (BMT). Because anesthesia for BMT is generally provided by face mask without placement of an intravenous catheter, an alternative route for analgesia administration is needed. Transnasal butorphanol is effective in relieving postoperative pain in adults and children. The effectiveness of transnasal butorphanol for postoperative pain management in children undergoing BMT was studied. METHODS: This double-blinded, placebo-controlled study compared the postoperative analgesic effects of transnasal butorphanol administered after the induction of anesthesia. Sixty children classified as American Society of Anesthesiologists physical status 1 or 2 who were aged 6 months or older and scheduled for elective BMT were randomized to receive transnasal placebo or 5, 15, or 25 microg/kg butorphanol. Postoperative pain was assessed using the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) on arrival in the postanesthesia care unit and at 5, 10, 15, 30, 45, and 60 min. RESULTS: The CHEOP scores were significantly less in the 25 microg/kg transnasal butorphanol group compared with controls. Significantly fewer children received rescue analgesia in the 25 microg/kg transnasal butorphanol group compared with controls (n = 1 and 8, respectively; P = 0.02). CONCLUSIONS: Transnasal butorphanol given in a dose of 25 microg/kg after induction of anesthesia provided adequate postoperative pain relief in children undergoing BMT.

Perioperative management of children with third degree heart block undergoing pacemaker placement: a ten year review.

It has been suggested that children with third degree heart block require insertion of a temporary pacemaker prior to general anaesthesia. This recommendation needs to be reevaluated with the availability of noninvasive transcutaneous cardiac pacing. We undertook a retrospective ten-year chart review of anaesthesia in children with third degree heart block undergoing pacemaker insertion or revision. Forty-eight children with complete heart block underwent seventy anaesthetics of which fifty three were in children without pacemakers or with nonfunctioning pacemakers. One child had a temporary pacemaker placed preoperatively following asystole in the emergency room. In children who were not being paced, 60% had baseline heart rates less than 60 bpm. Complications seen in this study, including hypotension, would not have been prevented by temporary pacemaker placement. We conclude that there is no benefit to routine preoperative temporary pacing in children with third degree heart block.

Postoperative analgesia with preoperative oral ibuprofen or acetaminophen in children undergoing myringotomy.

Previous studies have shown over 70% of children require analgesics following bilateral myringotomy and tube placement (BM&T). This double-blind, placebo-controlled study compared the postoperative analgesic effects of preoperatively administered oral acetaminophen or ibuprofen. Forty three ASA I or II children age six months or older scheduled for elective BM&T were randomized to receive acetaminophen (paracetamol) 15 mg.kg-1, ibuprofen 10 mg.kg-1, or placebo. Postoperative pain was assessed using the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) upon arrival to the PACU and at 5, 10, 15, 30, 45, and 60 min. CHEOP scores did not differ between the groups at any time. There was no difference in the number of children receiving rescue analgesia. This study showed no benefit of preoperatively administered oral ibuprofen 10 mg.kg-1 or acetaminophen 15 mg.kg-1 over placebo for the relief of postoperative pain in children undergoing BM&T.

Significance of atrial septal aneurysm: report of a case.

Postoperative stroke can have many etiologies including cerebral thrombosis, embolism, and hemorrhage. If there is a right-to-left intracardiac shunt, paradoxical embolism may also occur. Atrial septal aneurysm has been diagnosed with increasing frequency because of the accuracy of transesophageal echocardiography (TEE). Atrial septal aneurysm is also associated with patent foramen ovale and atrial septal defects. We report a case of a patient who developed a postoperative stroke one day after coronary artery bypass surgery. TEE performed in the intensive care unit revealed an atrial septal aneurysm with a right-to-left interatrial shunt, which may have resulted in paradoxical systemic embolism.

Changes in intraocular pressure during low dose intravenous sedation with propofol before cataract surgery.

AIMS: This study examined the effects on intraocular pressure, pulse rate, and blood pressure of low dose intravenous sedation with propofol. METHODS: Twenty adult patients who were scheduled to undergo cataract surgery were given a single intravenous bolus (0.98 (SEM 0.4) mg/kg) of propofol for sedation before administering the local anaesthetic for cataract surgery. A small intravenous dose of lignocaine was the only other anaesthetic or sedative agent given. The intraocular pressure in the non-surgery eye, the pulse rate, and the blood pressure were measured before and after propofol induction. RESULTS: Compared with the preinduction baseline, there was a 17% to 27% (from 16.2 (0.7) mm Hg to 11.8 (0.7) mm Hg) decrease in intraocular pressure after propofol induction. A significant decrease in intraocular pressure occurred within the first minute and was still evident at 7 minutes when the measurements were stopped. There was also a 7%-12% increase in pulse rate during the first 4 minutes, a 12% decrease in mean systolic blood pressure, and a 7% decrease in mean diastolic blood pressure from baseline after propofol induction. CONCLUSION: A single low dose bolus of propofol used for sedation before cataract surgery caused a moderate reduction in intraocular pressure with minimal, easily managed side effects.

Use of the flexible fiberoptic laryngoscope.

The flexible fiberoptic laryngoscope is an excellent instrument for performing tracheal intubation in patients with abnormal upper airway anatomy. In order to prepare to use the fiberscope for the infrequent patient with a "difficult" airway, the anesthesiologist must initially learn and practice the technique in patients with normal anatomy. Orotracheal intubation with the fiberscope in these patients receiving general anesthesia provides the anesthesiologist with abundant opportunities to become skillful.

Increased cerebral and decreased femoral artery blood flow velocities during direct laryngoscopy and tracheal intubation.

Direct laryngoscopy and tracheal intubation may be associated with increased heart rate, arterial blood pressure, cardiac index, and systemic vascular resistance. These responses have been attributed to sympathoadrenal stimulation. However, the studies measuring distribution of blood flow to various organs are limited. We prospectively evaluated blood flow velocities in the common carotid, middle cerebral, and femoral arteries before induction of anesthesia, after induction but before direct laryngoscopy, at the conclusion of direct laryngoscopy and tracheal intubation, and 3 min after tracheal intubation in 13 adult patients. Direct laryngoscopy and tracheal intubation produced increases in the heart rate (from 76 +/- 13 to 91 +/- 10 bpm; chi +/- SD), systolic blood pressure (from 168 +/- 20 to 206 +/- 21 mmHg), common carotid and middle cerebral blood flow velocities, but produced decreases in femoral artery blood flow velocities. Common carotid artery blood flow velocity increased from 49.4 +/- 12.5 cm/s to 65.2 +/- 20.7 cm/s (P < 0.05) at the conclusion of tracheal intubation. Middle cerebral artery blood flow velocity, which could be measured only in seven patients due to technical difficulties secondary to movement during laryngoscopy, increased from 62.4 +/- 20.5 cm/s to 78.0 +/- 27.7 cm/s (P < 0.05). In contrast, femoral artery blood flow velocity decreased from 107.6 +/- 37.8 cm/s to 76.8 +/- 28.6 cm/s (P < 0.05). These responses suggest that the hypertensive response due to direct laryngoscopy and tracheal intubation is associated with redistribution of blood flow in the body.

Brachial plexus block. A comparison of the supraclavicular lateral paravascular and axillary approaches.

BACKGROUND AND OBJECTIVES: Anesthesia of the brachial plexus has been associated with injuries to adjacent structures (e.g., pneumothorax, vascular penetration). It is not uncommon to have only partial block of the upper extremity, hindering completion of the surgical procedure. The supraclavicular lateral paravascular approach to brachial plexus anesthesia has been proposed as an effective, safe alternative to the traditional approaches to brachial plexus anesthesia. METHODS: This prospective, randomized study sought to determine if the supraclavicular lateral paravascular (SCLP) approach is as effective as the transarterial axillary approach, the most common brachial plexus block used at our institution. RESULTS: 16/20 (80%) of SCLP blocks were good. 13/20 axillary blocks were good. The success rate with the SCLP approach was 95%. The success rate with the axillary approach was 90%. CONCLUSIONS: The supraclavicular lateral paravascular approach is as effective as the axillary approach.

Excitatory effects and electroencephalographic correlation of etomidate, thiopental, methohexital, and propofol.

Excitatory movements have been observed during induction of anesthesia with etomidate, thiopental, methohexital, and propofol. We studied the frequency of these excitatory effects and correlated movements with electroencephalographic (EEG) findings in 67 unpremedicated patients (mean age 66.1 yr, range 45-82 yr). Excitatory effects, including myoclonus, tremor, and dystonic posturing, occurred in 86.6% of patients receiving etomidate; 69.2% of the patient responses were myoclonic. Multiple spikes appeared on the EEG in 22.2% of the etomidate patients. The frequency of excitatory effects was 16.6% after thiopental, 12.5% after methohexital, and 5.5% after propofol. None of the patients receiving thiopental, methohexital, or propofol developed myoclonic or seizure activity. In most patients, the excitatory movements were coincident with the early slow phase of the EEG which corresponds to the beginning of deep anesthesia. We conclude that perhaps caution should be exercised when administering etomidate to patients with a history of seizures as the myoclonic activity is associated with seizure activity. The incidence of excitatory movements after administration of propofol is very low.

Electroencephalographic changes from hyponatremia during transurethral resection of the prostate.

A patient undergoing transurethral resection of the prostate suffered hyponatremia during the perioperative period. Electroencephalography demonstrated diffuse slowing although the patient was not clinically encephalopathic. The serum sodium level may indicate a trend toward development of the transurethral resection syndrome but the sodium level does not necessarily parallel metabolic changes in brain tissue. Consequently, electroencephalography may aid in the early diagnosis and treatment of encephalopathy during the early phases of the transurethral resection syndrome.

Loss of hypoxic ventilatory response following bilateral neck dissection.

Modified radical neck or combined radical and modified radical neck surgery is performed for treatment of head and neck cancer. Because of the extensive nature of the surgery, including dissection around the carotid vessels, we prospectively evaluated hypoxic ventilatory responses preoperatively and postoperatively in five patients. The change in ventilation to percent desaturation varied between -0.22 and -0.60 L/min per percent desaturation in the five study patients. In the postoperative evaluation, two of five patients showed flattened responses compared with the preoperative measurements due to denervation of their carotid bodies. Two patients showed increased responses due to loss of upper airway resistance from tracheostomy. We conclude that after bilateral neck dissection for cancer surgery some patients may lose their hypoxic ventilatory responses due to carotid body denervation.

Influence of volume on the spread of local anesthetic-methylene blue solution after injection for intercostal block.

The purpose of this study was to evaluate the influence of the volume of methylene blue-local anesthetic on the spread of the injectate along the costal pleura. Twenty patients undergoing elective thoracotomy were studied. Twelve patients received intercostal nerve injection with 10 mL of 0.5% bupivacaine with methylene blue (10-mL group), and eight patients received 5 mL of 0.5% bupivacaine with methylene blue (5-mL group). The area of spread of the methylene blue was measured after the pleural cavity was incised. The 10-mL group had a mean area of spread of 51.1 cm2 as opposed to 17.6 cm2 for the 5-mL group (P less than 0.05). In the 10-mL group, eight patients had bupivacaine-methylene blue spread to two intercostal spaces, three patients to three intercostal spaces, and one patient to four intercostal spaces. In the 5-mL group, seven patients had bupivacaine methylene blue spread confined to one intercostal space and one patient to two intercostal spaces. We conclude that a potential anatomic space exists between the costal pleura and the internal intercostal muscle and that the spread of local anesthetic after intercostal nerve block injection is volume dependent.

An electroencephalographic comparison of effects of propofol and methohexital.

Thirty-eight patients were randomly allocated to receive propofol 1 mg/kg (group A, N = 10), methohexital 0.7 mg/kg (group B, N = 9), propofol 2 mg/kg (group C, N = 10), methohexital 1.5 mg/kg (group D, N = 9). They were all male with a mean age of 65.8 years (range, 46-85) and a mean weight of 76.2 kg (range, 50-109). Patients received no premedication. All drugs were administered as a single i.v. bolus. After baseline EEG recordings were obtained, i.v. bolus doses were given and the recording continued until the patients became fully responsive to verbal commands. The EEGs were visually analyzed and classified into 4 phases: phase 0, the wake physiologic pattern; phase 1, initial changes after i.v. bolus doses; phase 2, state of deep anesthesia; and phase 3, stage of recovery. The main change during phase 1 was increase in the amplitude of the background rhythms. Phase 2 was characterized by theta and delta activity and burst suppression in some patients. During phase 3 beta activity was seen following methohexital. Propofol produced a much deeper level of anesthesia compared to methohexital. The stage of deep anesthesia was prolonged following propofol. The clinical and EEG recoveries were prolonged after induction doses of propofol. The quality of recovery, however, was far superior with propofol. Methohexital produces a "hang over" effect which delays full recovery.