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H A Adams

Publications and source records attributed to H A Adams.

102 records · Page 6Linked to original sources

Influence of dextran on the absorption of adrenaline-containing lignocaine solutions: a protective mechanism in local anaesthesia.

The effect of adding 6% dextran to a lignocaine solution containing adrenaline was studied in 27 neurosurgical patients during modified neuroleptanaesthesia. Before trepanation they received infiltration anaesthesia of the scalp at the site of the proposed operation. For a period of 1 h following injection plasma concentrations of adrenaline were measured by high pressure liquid chromatography and serum concentrations of lignocaine by gas chromatography. The addition of dextran caused a significant reduction in the absorption of both adrenaline and lignocaine from the injection site. It is concluded that the dextran adjuvant constitutes a protective mechanism against toxic systemic side effects in local anaesthesia using adrenaline-containing anaesthetic solutions. This effect is particularly significant in patients with pre-existing cardiovascular disease and when local anaesthetic solutions are used in combination with volatile anaesthetics.

Absorption↗

[Effect of acebutolol on plasma catecholamines and perioperative endocrine stress parameters].

In order to investigate the effect of intraoperative beta-blockade with acebutolol on the endocrine stress response during modified neuroleptanesthesia, 20 patients for major abdominal or thoracic surgery from ASA groups I-III were randomly allocated to the following groups: (1) control group without acebutolol treatment; or (2) treatment group, administration of 0.2 mg/kg acebutolol 5 min after induction of anesthesia. During a period of 30 min before operation, intraoperatively, and 30 min after the end of operation plasma levels of norepinephrine and epinephrine (by HPLC) and ADH, ACTH, and cortisol (by RIA) were measured. In addition, mean arterial pressure (MAP), HR, and plasma concentrations of glucose, lactate, and free glycerol were determined. Statistical evaluation was undertaken by analysis of variance with repeated measures on one factor, considering P values of less than 0.05 as significant. The administration of acebutolol had no influence on plasma catecholamine concentrations during the preoperative rest period. There was no evidence of any interaction between beta-blockade and plasma catecholamines. After induction of anesthesia, the levels of all hormones decreased. During the operation, there was a significant increase in all endocrine parameters measured. No differences were found between the treatment and control groups. All endocrine parameters reached their highest levels 30 min after the end of the operation. The differences in MAP, HR, glucose, lactate, and free glycerol between the groups failed to reach statistical significance.

Acebutolol↗

[Effect of nimodipine on plasma catecholamines and perioperative endocrine stress parameters].

The influence of nimodipine on plasma-catecholamines, ADH, ACTH and cortisol during standardized, modified neurolept-anaesthesia was investigated in 20 patients for major abdominal and thoracic surgery. The application of nimodipine led to an intra- and postoperative increase in both adrenaline and noradrenaline. No influence could be demonstrated on ADH, ACTH or cortisol. Group-levels of MAP were lower in the nimodipine-group. No statistical differences became obvious for HR, glucose, lactate and free glycerol. The increases in adrenaline and noradrenaline can be attributed to a cardiocirculatory rebound-phenomenon due to the vasodilative properties of the substance. Under the conditions of adequate fentanylanalgesia, no influence of nimodipine on ADH, ACTH or cortisol was found.

Adolescent↗

[Sedative-analgesic medication in intensive care patients needing ventilator treatment].

UNLABELLED: It was the aim of this study to compare two regimens for sedation and analgesia during ventilator treatment in intensive care patients. Special regard was given to endocrine stress response, neuro-monitoring, hemodynamic parameters and clinical practicability. METHODS: A total number of 16 patients of an operative ICU were randomly allocated to the following groups: (1) Fentanyl-group, approximately 0.2 mg/h fentanyl, 2.5 mg/h midazolam and 2 mg/h pancuronium in intermittent doses, (2) ketamine-group, about 50 mg/h ketamine and 2.5 mg/h midazolam by syringe pump, in addition 2 mg/h pancuronium. During a period of 2 days and in intervalls of 6 h, plasma levels of epinephrine and norepinephrine (by HPLC/ECD), ADH, ACTH and cortisol (by RIA), ketamine (by GC) and stress-metabolites (glucose, lactate, free glycerol) were determined. Hemodynamic parameters were investigated in intervalls of 12 h, EEG (Compressed Spectral Array, CSA) in intervalls of 24 h. In addition, routine laboratory data, vigilance and adaptation to the respirator were observed. RESULTS: Plasma levels of adrenaline, noradrenaline, dopamine, ADH, ACTH, cortisol and stress-metabolites were comparable in both groups. Levels of ADH, ACTH, cortisol and free glycerol did not leave the normal range. In three patients, in which epinephrine- or norepinephrine-infusions were necessary to improve cardiocirculatory stability, this treatment could be finished after beginning of the ketamine application. In both groups, CSA showed a dominant delta- und theta-activity according to the clinical aspects of sufficient sedation and analgesia. Hemodynamic parameters were comparable in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Plasma concentrations of lidocaine and prilocaine following infiltration anesthesia in otorhinolaryngologic surgery].

UNLABELLED: Infiltration anaesthesia is still relevant for the surgical treatment of patients in otorhinolaryngology. The injection of local anaesthetics in well vascularised areas constantly causes the danger of high plasma concentrations of local anaesthetics combined with undesirable side effects. In our study we tried to determine the development of plasma concentrations of local anaesthetics in patients scheduled for routine tonsillectomies and tympanoplasty. MATERIALS AND METHODS: In 45 patients the development of plasma concentrations was measured immediately after the injection at short intervals; the samples were obtained between 1 minute and 60 minutes after the first injection. Group 1: Lidocaine 0.5% with epinephrine (1:200,000) 15-20 ml for tonsillectomy (n = 18). Group 2: Lidocaine 0.5% with epinephrine (1:200,000) 8-15 ml for tympanoplasty (n = 15). Group 3: Prilocaine 1% with epinephrine (1:200,000) 8-15 ml for tympanoplasty (n = 15). For tactical reasons infiltration anaesthesia for the patients of group 2 was - in addition to general anaesthesia - applied by the otorhinolaryngologist, whereas the patients of groups 1 and 3 were operated exclusively under local anaesthesia. RESULTS: Within the first minute after the initial injection plasma concentrations of the local anesthetic increased close to toxic threshold levels that are associated with undesirable systemic side effects. In the patients of group 1, who underwent tonsillectomy, plasma concentrations of 4-7 micrograms/ml were found during the first minute. The highest average values always appeared within the first five minutes: group 1 2.07 micrograms/ml, group 2: 0.45 micrograms/ml, and group 3: 1.15 micrograms/ml. DISCUSSION: With infiltration anaesthesia in well vascularised areas it may happen that there are--mainly in the early stage--high plasma concentrations of the applied substances, although the total dose was below the known maximum. Despite careful technique (repeated aspiration test in two levels) at least partial intravascular injections are apparently not always avoidable according to the pharmacokinetic data. Our results demonstrate that in addition to a safe peripheral venous line and prophylactic oxygen therapy, intraoperative monitoring of blood pressure, heart rate, electrocardiogram and verbal patient monitoring is of advantage in this group of patients. In our opinion the "standby function" of an anaesthesiologist can avoid severe complications.

Adolescent↗

[Reaction of the sympathetic nervous system, cardiovascular parameters and endocrine stress response in disobliterating interventions of the carotid arteries. A comparison of isoflurane anesthesia and modified neurolepto-anesthesia].

In order to investigate whether the increases in mean arterial pressure (MAP) and HR during carotid endarterectomy are due to a systemic, sympathicotonic stress response and to compare two anesthetic regimens for this operation, 20 patients were randomly allocated to the following groups: (1) modified neuroleptanesthesia with midazolam, fentanyl, and vecuronium: and (2) isoflurane anesthesia with vecuronium relaxation. Premedication (pethidine, promethazine) and induction of anesthesia were similar in both groups. The plasma levels of epinephrine and norepinephrine (by HPLC/ECD), ADH, ACTH, and cortisol (by RIA), glucose, lactate, and free glycerol were determined before and after induction of anesthesia, 7 times during the operation, and 30 min after extubation. MAP and HR were measured continuously. Statistical evaluation was undertaken by analysis of variance with repeated measures on 1 factor, considering P values of less than 0.05 as significant. The endocrine parameters failed to show any remarkable increase during the entire operation period. After the end of the operation all hormones rose significantly (P less than 0.001). No correlation was found between plasma catecholamines and increases in MAP and HR. Group levels of norepinephrine and ADH were higher in the isoflurane group (P less than 0.04). It is concluded that cardiovascular reactions during carotid endarterectomy are not caused by systemic stress. Neuroleptanesthesia leads to better stress protection in the postoperative period, while isoflurane anesthesia has some advantages for the intraoperative control of arterial pressure.

Adult↗

[Endocrine stress response in halothane, enflurane and isoflurane anesthesia in surgical interventions].

The endocrine stress response under inhalation anesthesia with halothane, enflurane, and isoflurane was investigated in 30 patients during and after orthopedic surgery (Table 2). Plasma levels of adrenaline and noradrenaline (by HPLC/ECD), ADH, ACTH, and cortisol (by RIA), glucose, lactate, and free glycerol were determined before induction of anesthesia, 10 min after intubation, 10 min before the end of the operation, and 5 and 30 min after extubation. Statistical evaluation was undertaken by analysis of variance with repeated measures on one factor. P values of less than 0.05 were considered significant. There were no significant differences in the concentrations of plasma catecholamines (Table 4, Figs. 1 and 2), ADH, ACTH (Table 5, Figs. 3 and 4), or cortisol before and during surgery between the groups. ADH was lower in the halothane group 5 and 30 min after extubation (P = 0.05), which might be due to the prolonged elimination of halothane after anesthesia. Blood pressure, heart rate (Table 3), and plasma concentrations of glucose, lactate, and free glycerol (Table 6) were comparable in all groups. It is concluded that for clinical practice halothane, enflurane, and isoflurane are comparable in their influence on the surgical stress response.

Adrenocorticotropic Hormone↗

[Effect of premedication and fentanyl administration on the endocrine stress reaction during halothane anesthesia].

The influence of two different premedication regimens (diazepam versus pethidine/promethazine with fentanyl substitution before induction) on the endocrine stress-response during halothane anaesthesia was investigated in twenty orthopedic surgery patients. After premedication, the levels of plasma catecholamines, ADH, ACTH and cortisol were lower in the pethidine/promethazine-than in the diazepam-group. The levels of adrenaline remained significantly lower during the whole observation period. Thirty minutes after extubation all endocrine parameters except noradrenaline were lower in the pethidine/promethazine-group than in the diazepam-group.

Adolescent↗

[Effect of the calcium antagonist nimodipine on hemodynamics, gas exchange and endocrine parameters in opiate anesthesia].

During opiate anesthesia (standardized dosage of fentanyl) for operation of cerebral aneurysms after subarachnoid hemorrhage, different hemodynamic, respiratory, metabolic, and endocrine parameters were determined before (1 in Fig. 1-4), after (6), and during consecutive stages of induced hypotension (systolic blood pressure 100 mmHg (2), 90 mmHg (3), 80 mmHg (4, 5) during an interval of 20 min), comparing two groups with different vasodilating drugs. In the first group (nimo/NNP in Figs. 2-4) a constant infusion of nimodipine was applied (1.2 micrograms/kg b.w. X min-1), while sodium nitroprusside (NNP) was added in small amounts as necessary to achieve the respective values of systolic blood pressure. In the second group (NNP in Figs. 2-4) induced hypotension was done with NNP alone (maximal dosage: 8 micrograms/kg X min-1). Each group consisted of 11 patients. Additional nimodipine (in the first group), a calcium antagonist commonly recommended for preventing vasospasm and consequent neurologic deficits after subarachnoid hemorrhage, not only reduced the need for NNP, a vasodilating drug with potential toxicity, by 70%-80% as compared to the second group (Table 1). In addition, the cardiovascular situation was more stable in patients with nimodipine infusion: rapid variations of blood pressure and heart rate as well as tachyphylaxis and rebound, typical for NNP-induced hypotension, were avoided. Nevertheless, comparing the hemodynamic data at fixed stages of hypotension, there were only minor differences between both groups (Fig. 2). Reduction of blood pressure was due to a decrease in vascular resistance and was accompanied by an increase in cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, General↗

[The endocrine stress-reaction to orotracheal intubation and topical anesthesia with lidocaine].

The influence of laryngoscopy and intubation with or without topical lidocaine anesthesia on the endocrine stress response was investigated in six groups of 40 orthopedic surgery patients differing in premedication and technique of lidocaine application (one- or two-step method). Controls were included without lidocaine application. Plasma levels of catecholamines (by HPLC) were measured before induction and 1, 5, and 10 min after intubation, ADH-levels (by RIA) before induction and 5 and 10 min after intubation. In addition, mean arterial pressure (MAP, MAP), HR, and the incidence of coughing and cardiac arrhythmias were observed. The statistical evaluation (analysis of variance with repeated measures on one factor) considered P values of less than 0.05 significant. There was no influence of laryngoscopy and intubation on plasma catecholamine levels during the observation period. A continuous decrease in both levels of epinephrine and norepinephrine was significant. ADH levels showed no significant changes. Lidocaine had no influence on these endocrine parameters. MAP and HR increased after intubation in all groups studied. The increase in HR was less pronounced after lidocaine treatment. Coughing (4 patients) and ventricular dysrhythmia (2 patients) were observed only in patients without lidocaine treatment. In conclusion, no influence of different modes of treatment on the endocrine stress response during intubation became obvious. There was no indication that the cardiovascular symptoms during laryngoscopy and intubation are caused by systemic stress. An explanation may be a direct neural impulse via sympathetic efferents to the heart. On the other hand, topical application of lidocaine did prevent coughing and cardiac irritation, and the increase in HR was attenuated.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗

[Sexually transmitted diseases in a crew of a destroyer on a voyage to Far East (author's transl)].

21 cases of gonorrhea, some with very long incubation periods, were treated either with 3 x 4 Mega Clemizol-Penicillin G (13 cases) or with 2 x 2 gr. Spectinomycin (8 cases). Thereby a complete cure was achieved in 14 cases (66, 6%), whereas in 2 cases after treatment with Penicillin no complete cure could be accomplished. A non-gonorrhean urethritis (NGU) occurred in the case of 5 patients (24%). Treatment by Doxycyclin was successful but in one case 10 days of treatment proved to be too short so it was necessary to extend the period to 14 days for reasons of safety. The same applies to treatment of nongonorrhean urethritis. In the therapy of granuloma venereum Cotrimoxazol proved to be even more effective than tetracycline. However, it has to be taken into consideration that the disease had been yet in a process of healing.

Gonorrhea↗