Biomedical subjects

J Kyttä

Publications and source records attributed to J Kyttä.

At least 19 recordsLinked to original sources

PubMed1999

Patient-controlled analgesia with oxycodone in the treatment of postcraniotomy pain.

BACKGROUND: Moderate to severe pain occurs after craniotomy in 60% of patients. We evaluated the feasibility and safety of patient-controlled analgesia (PCA) with oxycodone in neurosurgical patients, and compared the efficacy of paracetamol with ketoprofen. METHODS: In the study there were 45 patients, who received either paracetamol 1000 mg or ketoprofen 100 mg three times a day. Oxycodone-boluses 0.03 mg/kg were given by PCA-device maximally three times an hour, lock-out time 10 min. The amount of oxycodone used, pain scores and side-effects were recorded. RESULTS: The ketoprofen group required less oxycodone than the paracetamol group (medians 37.1 mg vs 19.6 mg, P < 0.05). The VAS scores were comparable between the groups at the beginning of the study, during the first postoperative evening and the next morning, but the paracetamol group had a higher score at the conclusion of the study (P < 0.05). The patients in both groups were equally satisfied with the pain relief. There were no differences in side-effects between the groups. CONCLUSIONS: PCA with oxycodone is a suitable method for pain control after craniotomy. No progressive hypoventilation, desaturation or excessive sedation were encountered. Ketoprofen appeared to be more effective than paracetamol.

Acetaminophen↗

PubMed1999

QT dispersion after subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) causes a stress response with increased concentrations of plasma catecholamines and serious cardiac arrhythmias. Increased QT dispersion has been shown to predispose to cardiac arrhythmias. In SAH patients, QT dispersion has not been studied previously. QT dispersion was analyzed in 26 patients with SAH and in 16 patients (control group) scheduled for ligation of a nonruptured cerebral aneurysm. In 15 patients with SAH, the plasma concentrations of catecholamines were analyzed, and an 18-hour continuous electrocardiogram (ECG) recording was obtained. In the other 11 patients, electrocardiography was repeated daily for up to 9 days for analysis of QT dispersion. The median (25th and 75th percentiles) QT dispersion in all SAH patients was 78 milliseconds (50 and 109 milliseconds, respectively), and in control patients, it was 25 milliseconds (15 and 33 milliseconds, respectively) (P < .001). There was a positive correlation with QT dispersion and the plasma concentration of DHPG, a metabolite of norepinephrine (P < .05). All patients had episodes of cardiac arrhythmia during the 18-hour recording period. In conclusion, increased QT dispersion is a common finding after SAH and may be a result of high plasma concentrations of catecholamines in these patients.

Adrenergic Agonists↗

PubMed1999

Extracranial contribution to cerebral oximetry in brain dead patients: a report of six cases.

The near infrared spectroscopy offers a noninvasive method to monitor regional brain oxygenation. The problem with the technique appears to be possible extacranial contribution to the measurements. As a part of another study, we monitored regional saturation (rSO2) in six brain dead patients either during the test for spontaneous respiration or in those not eligible for organ donation, after discontinuation of mechanical ventilation. Relatively normal rSO2 values were obtained after brain death, and the values decreased concomitantly with the hemoglobin saturation of oxygen (SpO2) after the discontinuation of mechanical ventilation. A corresponding decrease in SpO2 and rSO2 suggests extracranial contribution to the measured rSO2. The diagnosis of brain death cannot be made based on this technology; furthermore the presence of extracranial contribution may limit its potential value even in other applications.

Adult↗

PubMed1998

The best view at laryngoscopy using the McCoy laryngoscope with and without cricoid pressure.

The best view obtained by levering the tip of the McCoy laryngoscope blade with or without modified cricoid pressure was studied in 100 patients presenting for general surgery. The airway was assessed pre-operatively (Mallampati score, thyromental distance, mouth opening, protrusion of the jaw and weight) in an attempt to identify the patients who might benefit from the use of the McCoy laryngoscope. The vocal cords were visible at laryngoscopy with the blade in the neutral position in 32 cases. In the 68 remaining patients the vocal cords were partly visible in 48. The epiglottis only was seen in 18 patients and in two not even the epiglottis could be visualised. Elevation of the blade or modified cricoid pressure improved the view in 38/68 cases and 57/68 cases, respectively (p < 0.001, Wilcoxon signed rank). Using our method of pre-operative assessment we were unable to identify those patients who might benefit from either manipulation.

Adult↗

PubMed1998

The relevance of clinical and radiological measurements in predicting difficulties in fibreoptic orotracheal intubation in adults.

Resistance to the passage of the tracheal tube has been reported to occur in up to 36% of patients subjected to orotracheal fibreoptic intubation. In this prospective study we assessed five radiological measurements of the upper airway in an attempt to find anatomical causes of obstruction to passage of the tube. Forty-nine patients undergoing fibreoptic orotracheal intubation under general anaesthesia were studied. Pre-operatively, the Mallampati grade and the thyromental distance were assessed. The plain films, CT scans or MR images of the cervical spine were used for measurement of the position of the vocal cords, the length of the epiglottis and the size of the tongue. The resistance to the passage of the tube was graded as none, mild, moderate or severe. The length of the epiglottis and the size of the tongue, but not the position of the vocal cords, had positive correlations with the severity of impingement. The pre-operative bedside tests did not correlate with difficulties in fibreoptic intubation.

Adult↗

PubMed1997

Knee-chest vs horizontal side position during induction of spinal anaesthesia in patients undergoing lumbar disc surgery.

In the prone knee-chest position the spread of plain 0.5% bupivacaine in the cerebrospinal fluid and associated haemodynamic changes may be different compared with the horizontal position. A randomized comparison was performed in 40 ASA I-II patients, aged 24-61 yr, undergoing lumbar disc surgery. Subarachnoid injection (27-gauge needle) at the L2-3 interspace with 3 ml of 0.5% bupivacaine was performed with the patient in the operative knee-chest position (prone knee-chest group, n = 20) or in the horizontal side position (supine side horizontal group, n = 20). Patients in the supine side horizontal group were turned into the horizontal supine position for 20 min, and subsequently they were placed in the operative knee-chest position. In three patients in the prone knee-chest group, the spinal needle was replaced by a larger needle (25-gauge). The final cephalad extension of sensory analgesia on skin tested by pinprick was T5 (median) in the prone knee-chest group and T6 in the supine side horizontal group. Recovery was also similar, on average 210 min from injection in both groups. The mean decrease in systolic arterial pressure was somewhat greater in the prone knee-chest group (30 mm Hg) than in the supine side horizontal group (13 mm Hg). The need for ephedrine occurred earlier in the supine side horizontal group (three patients, all within 10 min from local anaesthetic injection) than in the prone knee-chest group (six patients, all after 15 min). Four of the latter patients also required administration of an anticholinergic for bradycardia compared with two patients in the supine side horizontal group. Light sedation was given to five patients in the prone knee-chest group and to four in the supine side horizontal group because of numbness and aching in the shoulders. We conclude that spinal block was similar in the two groups but there was a tendency to more frequent episodes of haemodynamic deterioration in the knee-chest position.

Adult↗

PubMed1997

The effect of patient positioning on dynamic lung compliance.

BACKGROUND: Side-stream spirometry offers a non-invasive method to monitor continuously respiratory mechanics in intubated patients. We studied the effects of different positions on dynamic lung compliance during anaesthesia. METHODS: The study consisted of 56 patients, operated in supine, prone, kneeling or lateral park-bench position. Dynamic lung compliance and inspiratory peak pressure were recorded after induction of anaesthesia, 15 min and 1 h after posturing the patient. RESULTS: The first measured compliances were comparable in all groups. The compliance in the lateral and the prone positions was significantly lower than in the supine position at 15 min (P < 0.01) and 1 h (P < 0.001) after the posture change. The peak inspiratory pressure was significantly lower in the kneeling position than in the other groups (P < 0.01 at the first measurement, P < 0.001 at the later measurements). No correlation was found between body mass index and compliance. CONCLUSION: We found that dynamic lung compliance decreased significantly upon change of posture from supine to lateral or prone position, whereas in the kneeling position no change in compliance was observed. We suggest that the kneeling position might be preferable to the prone position.

Adult↗

PubMed1996

Comparison of the effects of controlled ventilation with 100% oxygen, 50% oxygen in nitrogen, and 50% oxygen in nitrous oxide on responses to venous air embolism in pigs.

In this randomized, experimental study in 18 pigs, we have investigated the effects of inspiratory air in oxygen, 100% oxygen and 50% nitrous oxide in oxygen on the detection and consequences of venous air embolism. Each animal was tested with injections of 1.0 ml kg-1 and 2.0 ml kg-1 of air. All animals, except one in the nitrous oxide group, survived the air emboli. Systolic and diastolic arterial pressures decreased significantly in all groups after both injections of air. Pulmonary diastolic pressures increased most in the nitrous oxide group. End-tidal concentration of carbon dioxide decreased significantly in all groups after air injections. The difference in concentration of oxygen in the inspiratory and expiratory gas (O2 (I-E)) was lowest in the air group after both injections of air. On the basis of our studies we suggest that nitrous oxide should not be used during surgery associated with an increased risk of venous air embolism.

Anesthetics, Inhalation↗

PubMed1995

Monitoring lung compliance and end-tidal oxygen content for the detection of venous air embolism.

Venous air embolism (VAE) is a recognized complication of surgery performed with the patient in the sitting position, but it occurs also during other operations. We report two cases of VAE, associated with a notable decrease in dynamic lung compliance, detected by side-stream spirometry. Based on these cases, an experiment with 10 pigs was designed to evaluate the usefulness of side-stream spirometry in the diagnosis of VAE. Three doses of air (0.5, 1.0 and 2.0 ml kg-1) were injected via the proximal part of a 5- French gauge pulmonary artery catheter. Only the largest dose was followed by haemodynamic deterioration. Significant increases in end-tidal oxygen content and decreases in dynamic lung compliance were detected with all doses of air together with conventional signs of VAE, that is increases in pulmonary artery pressures and arterial carbon dioxide tensions, and decreases in end-tidal concentration of carbon dioxide. We conclude that continuous monitoring of end-tidal oxygen concentration and side-stream spirometry offers valuable supplements to other monitoring techniques in the detection of VAE.

Adult↗

PubMed1995

Anaphylactoid skin reactions after intravenous regional anaesthesia using 0.5% prilocaine with or without preservative--a double-blind study.

Methylparaben, the preservative of various local anaesthetic solutions, is a potential allergen. In a double-blind study, 0.5% prilocaine with (Citanest, n = 100) or without (n = 100) methylparaben were compared for the occurrence of skin reactions after intravenous regional anaesthesia of the arm in surgical patients. Skin reactions were registered after the deflation of the tourniquet cuff, and intradermal tests were performed with 0.5% prilocaine, 0.1% methylparaben and saline in all patients. Seventeen patients in the Citanest group and four patients in the methylparaben-free prilocaine group developed erythematous skin reactions in the exposed arm after deflation of the tourniquet cuff (P < 0.05, between the groups). The skin symptoms disappeared within an hour and were always restricted to the region which had been anaesthetised. None of the affected patients had positive intradermal tests. The observed skin reactions are probably non-IgE-mediated anaphylactoid reactions in which the presence of methylparaben in the local anaesthetic solution plays a major role.

Adult↗

PubMed1993

Comparison of 2-chloroprocaine and prilocaine for intravenous regional anaesthesia of the arm: a clinical study.

In a double-blind, randomised study of patients scheduled for minor hand surgery 0.5% 2-chloroprocaine (n = 30) and 0.5% prilocaine (n = 30) in a volume of 40 ml were compared for intravenous regional anaesthesia. The onset of sensory and motor block and recovery of sensory block were determined, and the occurrence of side-effects was noted. Twenty-four patients in the 2-chloroprocaine group and 17 in the prilocaine group developed complete sensory block by 15 min after injection (p < 0.05). Complete recovery of sensation was faster after prilocaine (7.1 min) than 2-chloroprocaine (9.8 min) (p < 0.01). Venous irritation and/or urticaria after tourniquet release was observed on 10 occasions in those receiving 2-chloroprocaine and twice in those receiving prilocaine. An increase in heart rate of > 20% above control values occurred in three patients, all of whom had been given 2-chloroprocaine. Clinically, local anaesthetic properties of 0.5% 2-chloroprocaine and prilocaine were similar, but there were more side-effects with the former drug.

Adolescent↗

PubMed1992

The effect of amrinone on recovery from severe bupivacaine intoxication in pigs.

Cardiovascular collapse following intravascular bupivacaine may be resistant to treatment. The effect of amrinone on recovery from bupivacaine-induced severe cardiovascular depression was evaluated in 20 pigs (13-26 kg) in a placebo-controlled randomized double-blind study. Under 0.7% isoflurane anesthesia at FIO2 0.21, 0.5% bupivacaine 2 mg.kg-1.min-1 was infused until mean arterial pressure was 40% of the baseline. Cardiac output and heart rate decreased 75% and 50% from the baseline, respectively. The total dose of bupivacaine was 17 +/- 6 (SD) mg.kg-1 in the control and 19 +/- 5 mg.kg-1 in the amrinone group, resulting in mean plasma concentrations of 42 +/- 6 and 53 +/- 19 micrograms.ml-1, respectively. A bolus of amrinone 4 mg.kg-1 (n = 10) was given immediately after cardiovascular depression, followed by an infusion of 0.6 mg.kg-1.min-1. The control animals received corresponding volumes of physiologic saline (n = 10). After cardiovascular depression, the lungs were ventilated with FIO2 1.0 without anaesthetics or sympathomimetic support. Electric activity of the heart ceased in all control animals in 3.9 +/- 2 min after cardiovascular depression despite atropine and external cardiac compression. All animals in the control group and 5 of 10 animals in the amrinone group were given atropine (P less than 0.01). The animals receiving amrinone survived without cardiac compression (P less than 0.0001). During bupivacaine infusion, all animals developed burst suppression in the electroencephalogram. At the time of cardiovascular depression, in 8 of 10 control and in 6 of 10 amrinone animals, the electroencephalogram was isoelectric.(ABSTRACT TRUNCATED AT 250 WORDS)

Amrinone↗

PubMed1988

Comparison of propofol and methohexitone anaesthesia for thermocoagulation therapy of trigeminal neuralgia.

Propofol and methohexitone given in equipotent doses were compared for anaesthesia for thermocoagulation of trigeminal rootlets. Thirty-eight patients received two to six injections of the induction agents in one therapy session. The increase in arterial blood pressure during coagulation was significantly lower in the propofol group. Respiratory problems were encountered more often in those who received methohexitone (7/19 patients) than propofol (2/19 patients). There was a small but significant increase in blood propofol concentrations as well as in methohexitone plasma concentrations after repeated injections. Individual wake-up times increased to a statistically significant extent in relation to the number of doses of the induction agent but the increases were clinically unimportant (maximal mean change approximately 2 minutes). There were no differences in wake-up times between the two anaesthetic groups.

Adult↗

PubMed1988

Results of a randomized trial of vancomycin prophylaxis in craniotomy.

A single prophylactic dose of vancomycin was given in 143 supratentorial craniotomies with a bone flap and 26 suboccipital craniotomies. No antimicrobial agents were given to two similar groups of patients: 172 with supratentorial craniotomy and 19 with suboccipital craniotomy. The infection rate in the vancomycin groups was significantly lower (p less than 0.013), and bone-flap infections alone, the most common infection after supratentorial craniotomy, were significantly fewer (p less than 0.042). Antimicrobial prophylaxis is recommended only for selected high-risk groups. Since a bone flap is devascularized, its resistance to infection is reduced and, once infected, it usually requires surgical removal. Patients undergoing craniotomy with a bone flap therefore form a high-risk group, and antimicrobial prophylaxis is justified.

Adult↗

PubMed1987

Arterial hypertension associated with the use of a tourniquet with either general or regional anaesthesia.

A hypertensive patient with left cardiac enlargement developed marked hypertension under general anaesthesia, during which time a tourniquet was applied around his thigh. When the tourniquet was released, severe hypotension ensued which responded to therapy. The patient, however, died 16 h later of a myocardial infarction. Because of this incident, the anaesthetic and haemodynamic data of 699 patients who underwent limb surgery with a pneumatic tourniquet inflated for at least an hour were retrospectively examined using multivariate analysis. A 30% increase in systolic and/or diastolic arterial blood pressure occurred in 27% of the total patient material and in 67% of those who had had a general anaesthetic. There was a higher frequency of the occurrence of "tourniquet hypertension" with older age, longer operations and the operation site being the lower rather than the upper limb. Tourniquet hypertension rarely occurred in patients with spinal anaesthesia (2.7%) and brachial plexus blockade (2.5%), while those with intravenous regional anesthesia had a higher incidence (19%) of hypertension.

Adolescent↗

PubMed1987

Comparison between 0.5% bupivacaine with and without glucose in lumbar epidural block for knee surgery.

A double-blind study was performed in 41 patients (ASA I) to compare 0.5% bupivacaine with and without 8% glucose in epidural analgesia. There was no difference in the onset, spread, duration or intensity of the epidural anaesthesias. The absorption of bupivacaine to circulation was similar in both groups. No major complications were noted and the anaesthesias were satisfactory for surgery in all patients.

Adult↗

PubMed1986

Absorption of bupivacaine, etidocaine, lignocaine and ropivacaine into n-heptane, rat sciatic nerve, and human extradural and subcutaneous fat.

Absorption of four amide local anaesthetics, including a new experimental agent, ropivacaine, in n-heptane, rat sciatic nerve and human extradural and subcutaneous fat was studied in vitro. The relative n-heptane/buffer (37 degrees C) partitioning of bupivacaine:etidocaine:lignocaine:ropivacaine was 10:39:1:2.9. The absorption of bupivacaine and etidocaine into nerve tissue was identified at steady state, but in extradural and subcutaneous fat etidocaine was taken up significantly more than bupivacaine. The lowest uptake was with lignocaine, and at steady state its mean concentrations were similar in all three tissues. There was a significantly higher concentration of ropivacaine than lignocaine in all tissues. Mean tissue concentrations of bupivacaine in sciatic nerve and subcutaneous fat, on the other hand, were significantly higher than those of ropivacaine. The ratios of relative mean uptake (mg g-1), at steady state, of bupivacaine, etidocaine, lignocaine and ropivacaine were: sciatic nerve 3.3:4:1:1.8, extradural fat 4.1:8.3:1:2.3 and subcutaneous fat 3.8:10.6:1:1.9, all of which were clearly lower than the theoretical n-heptane/buffer partitioning ratios.

Absorption↗

PubMed1986

Effects of repeated bupivacaine administration on sciatic nerve and surrounding muscle tissue in rats.

The effects of repeated administration of 0.5% bupivacaine or saline into the sciatic notch of rats were studied by light microscopy, electron microscopy and a neurophysiological technique. Very severe myositis, including local necrosis, developed in six of 12 rats treated twice daily with 1 ml bupivacaine for either 3 or 7 days. A 3-h infusion of 1.5 ml 0.5% bupivacaine resulted in minor injury to muscle tissue. A marked degree of disruption and vacuolization of myelin sheaths was evident in nerves exposed to bupivacaine for 3 days. Lymphocyte accumulation was confined to the area surrounding the nervous tissue in 7 of 10 of the preparations from rats treated for 3 days or by a 3-h infusion. No histological changes were detected in nerve and muscle tissue from the opposite extremity exposed to saline. After a recovery period of 3 weeks, no differences in the nerve or muscle histology were seen between samples from bupivacaine- or saline-treated animals. The amplitude of the compound action potential of sciatic nerves was, however, significantly lower after bupivacaine treatment (7 days, 1 ml twice daily). Thus, impaired function may continue despite the lack of histological intraneural injury.

Animals↗