A scoring system for basic cardiac life support skills in training situations.

A valid and reproducible system for determining basic cardiac life support (BCLS) skills can help to evaluate the effect of instruction courses and to estimate the results of educational activities. The aim of this study was to develop and test such a system in accordance with the Standards and Guidelines of the American Heart Association (AHA). Five criteria were defined in advance towards such a system (1) Inadequate techniques must be reflected by a fail score. (2) Skilled persons should achieve a pass score. (3) The effect of training must be reflected by an improvement of the score. (4) Inter- and intra-observer variability must be negligible. (5) The system should be simple to apply. The system was developed, and in order to test the system, the BCLS skills of 40 ambulance nurses were tested once and those of 148 lay people twice. All cardiopulmonary resuscitation (CPR) attempts were performed on a mannequin. The relevant parameters of the attempt were continuously recorded and printed. Penalty points were assigned in a predefined way for aberrations of the techniques advised in the Standards and Guidelines. The system satisfied the five criteria mentioned above. It therefore offers a reliable and reproducible evaluation of BCLS skills.

Cardiopulmonary resuscitation on the general ward: no category of patients should be excluded in advance.

In this study 91 consecutive CPR cases in 90 patients on general wards were evaluated during 18 months. Fifteen patients (16.5%) could be discharged, which is relatively favourable in comparison to the literature. Children proved to have a better chance to leave the hospital alive than adults (6/18 vs. 9/72; P less than 0.05). No factors with negative predictive value before the cardiopulmonary arrest could be isolated. Even oncological patients, often described as a prognostically poor category, with a success rate of 27% (6/22) did not differ from other categories. Patients with isolated respiratory arrest, ventricular tachycardia or ventricular fibrillation at the arrival of the CPR-team had a better chance to be discharged from the hospital. A rapid decrease in survival was noted if a CPR attempt lasted longer than 10 min (P less than 0.001). When there is no return of vital signs within 30 min the CPR attempt can be stopped. During follow-up period (mean 6 month) 2 of the 15 survivors (13.3%) died from a non-cardiopulmonary cause. It is concluded that no category of patients can be excluded from CPR in advance. Although ultimate success rate for CPR in the general wards will rarely exceed 15%, CPR has to be initiated in most cases of cardiopulmonary arrest.

Potentiation of neostigmine and pyridostigmine by 4-aminopyridine in the rat.

The interaction between 4-aminopyridine and neostigmine or pyridostigmine was studied in vivo in the rat sciatic nerve-anterior tibialis preparation using the constant infusion of pancuronium technique. The ED50 (dose of drug which produced a 50% antagonism) of neostigmine, pyridostigmine and 4-aminopyridine were 18, 49 and 440 microgram kg(-1) respectively. The addition of 100 microgram kg(-1) of 4-aminopyridine, which produced no antagonism by itself, decreased the neostigmine ED50 to 7.4 microgram kg(-1). The addition of 200 microgram kg(-1) of 4-aminopyridine, which produced a 30% antagonism by itself, decreased the ED50 of pyridostigmine to 11 microgram kg(-1). We conclude that both neostigmine and pyridostigmine interact with 4-aminopyrine synergistically.

Effect of some benzodiazepines on peripheral neuromuscular function in the rat in-vitro hemidiaphragm preparation.

The effect of equimolar cumulative concentrations of 11 different benzodiazepines on the indirectly evoked twitch contraction was investigated in the rat in-vitro phrenic nerve-hemidiaphragm preparation. Depending on the pattern of the concentration-response curves two groups of benzodiazepines can be distinguished: (i) a first group with a biphasic action, e.g. potentiation of twitch tension in low concentrations and depression of twitch tension in high concentrations, and (ii) a second group with primary depression of twitch tension with increasing concentrations. All of the tested compounds ultimately caused a 100% depression of twitch tension at concentrations ranging from 0.175 to 0.35 mmol litre-1. Although this peripheral effect of benzodiazepines on neuromuscular function is not the main site of action of these compounds, there are enough arguments to state that it is not a simple toxic effect. There is some evidence from this study that the peripheral component of the benzodiazepine effect on muscle relaxation may involve a multi- rather than one single receptor system.

The role of anesthesiology in the health care system of The Netherlands.

With the initiation of regular anesthesia services in the Netherlands in 1947, anesthesiology has grown to a large and influential profession, including intensive care, resuscitation, pain therapy, and emergency medical care. Pre- and postgraduate training programs are formalized and compete with some of the best in the world. After a long struggle, anesthesiology's social and legal status now compares with all other medical sciences. Anesthesia is restricted to medical specialists, but with the permanent support of fully trained and qualified nurses. Anesthesia in the Netherlands is a "two person" job.

Interaction of antibiotics on pipecuronium-induced neuromuscular blockade.

STUDY OBJECTIVE: To measure the interaction of two antibiotics (clindamycin and colistin) on neuromuscular blockade induced by pipecuronium bromide (a new long-acting, steroidal, nondepolarizing neuromuscular blocking drug). DESIGN: Prospective, randomized, placebo-controlled study. SETTING: Inpatient gynecologic and gastroenterologic service at a university medical center. PATIENTS: Three groups of 20 ASA physical status I and II patients with normal kidney and liver function, taking no medication, and undergoing elective surgery under general anesthesia. INTERVENTIONS: Anesthesia was induced with propofol and alfentanil intravenously (IV) and maintained with a propofol infusion and 60% nitrous oxide in oxygen. Pipecuronium bromide 50 micrograms/kg was administered after reaching a stable baseline of single-twitch response. At 25% recovery of pipecuronium-induced neuromuscular blockade, patients received one of two antibiotics, clindamycin 300 mg or colistin 1 million IU, or a placebo. MEASUREMENTS AND MAIN RESULTS: The recovery index (RI, defined as time from 25% to 75% recovery of neuromuscular blockade) was measured using the single-twitch response of the adductor pollicis muscle with supramaximal stimulation of the ulnar nerve at the wrist. RI after administration of an antibiotic (given at 25% recovery) was measured and compared with RI of the control group using Student's unpaired t-test. Statistical analyses of the results showed a significant prolongation of the recovery time (from 25% to 75% recovery) of 40 minutes for colistin. CONCLUSIONS: When this type of antibiotic is used during anesthesia with pipercuronium as a muscle relaxant, one must be aware of a significant prolongation of an already long-acting neuromuscular blockade and (although not observed in this study) possible problems in antagonism.

Pharmacokinetics of diazepam and four 3-hydroxy-benzodiazepines in the cat.

Biotransformation and elimination of diazepam and four 3-hydroxy-benzodiazepines after i.v. injection in anaesthetized cats were investigated. Decay of plasma concentration of 3-hydroxy-benzodiazepines was slow and plasma concentrations of their glucuronides were lower than of unchanged parent compounds. In the urine, very low excretion rates of all investigated benzodiazepines were found during the first eight hours. It is concluded that cats poorly glucuronidate 3-dydroxy-benzodiazepines.

The role of the recovery room for the safety of anesthesia.

Three groups of activities taking place in the recovery room are separately analyzed and compared with the same done on the wards. It is concluded that all three of them are preferably done in the recovery room. When these principles are followed, mortality in the direct postoperative period can be reduced to an absolute minimum. Data from 50,000 cases confirmed this statement.

Muscle relaxants for out-patient procedures.

The requirements for muscle relaxation in out-patient anesthesia are: a short total relaxation enabling the induction of an endotracheal tube followed by a period of 15-20 minutes of clinical relaxation. Reversal should be spontaneous. The new short acting muscle relaxants vecuronium and atracurium enable such a procedure, provided small doses are used (0.045 mg/kg for vecuronium or 0.2 mg/kg for atracurium. These small doses require a longer waiting time before intubation is easily performed (5 min for vecuronium and 6 min for atracurium). Spontaneous reversal of these small doses is achieved within 20-30 minutes. Potentiation of the relaxation by inhalational agents is not recommended.

The comparative influence of gamma-hydroxy butyric acid, althesin and etomidate on the neuromuscular blocking potency of pancuronium in man.

The potentiating effect of gamma-hydroxy butyric acid (GHB), Althesin and etomidate on pancuronium was studied in man. GHB proved to influence pancuronium the least whereas Althesin and etomidate potentiate considerably. It is concluded that the amount of non-depolarizing relaxant needed depends on the type of anesthesia given. For neuromuscular blocking studies, GHB and/or thiopentone anesthesia seem to be preferable.

Effect of tetrahydroaminoacridine and 4-aminopyridine on recovery from ketamine-diazepam anesthesia in the macacus rhesus monkey.

Tetrahydroaminoacridine (T.H.A., Tacrine) 1 mg/kg, and 4-aminopyridine (Pymadin) 0.2 and 1.0 mg/kg i.v., significantly reduced the recovery time when the were administered after ketamine-diazepam anesthesia in Maccacus Rhesus monkeys. Anesthesia was induced with ketamine (50 mg), diazepam (1.2 mg) and sodium glycopyrrolate (0.02 mg) as a secretiondrying agent, as a single bolus injection. Anesthesia was continued with ketamine by constant infusion of a solution of 5 mg/ml, at a speed of 20 mg/ml, at a speed of 20 ml/hour, during 30 minutes. The 5 monkeys in the control group were allowed to recover spontaneously. The test series consisted of the same monkeys, with an adequate rest period of one or more weeks between anesthesias. Recovery was indicated by production of nystagmus, and by an awake pattern in the EEG. Clinical signs, restlessness and purposeful movements, were also used.

The efficacy and safety of nalbuphine (NUBAIN) in balanced anesthesia. A double blind comparison with fentanyl in gynecological and urological surgery.

In a prospective double blind study the efficacy and safety of nalbuphine as an analgesic in balanced anesthesia has been compared to fentanyl. In 63 patients, ASA class I-III, major gynecological or urological surgical procedures were performed under balanced anesthesia. Analgesia could be satisfactory maintained in all cases, but in cases of nalbuphine more hypnotics were necessary to keep the patients unconscious. The ratio of fentanyl and nalbuphine consumption was 1:200 (by weight). The nalbuphine cases can be distinguished by: more stable but higher arterial pressures and absence of arrythmia; lower incidence of nausea and vomiting in the postoperative period; less respiratory depression at the end of anesthesia, not needing antagonists, as compared to 11 patients needing antagonization in the fentanyl group; and a larger incidence of minor local allergic reactions at the injection site. Awareness was not observed in any patient of either group. Although nalbuphine has a weaker analgesic and hypnotic effect, it is perfectly possible to provide balanced anesthesia in combination with a hypnotic and a muscle relaxant. Advantages are the absence of respiratory depression as well as nausea and vomiting in the postoperative period.

Continuous infusion of etomidate as a method for outpatient anesthesia.

Fourteen, ASA class 1 or 2, outpatients of either sex, admitted for elective arthroscopy of the knees, were anesthetized by continuous infusion of etomidate. After a mean infusion time +/- SD of 38.2 +/- 11.6 min., the awakening time was 4.96 +/- 3.29 min. Five patients (37.7%) had mild pain on the injection side and 3 (21.5%) showed myoclonic movements. Postanesthetically 6 patients (42%) were nauseated and 4 (28.5%) were vomiting. After 130.4 +/- 38.33 min. all patients could be sent home. It is concluded that continuous infusion of etomidate is unless these side effects a good alternative anesthesia technique for outpatients. (Acta anaesth. belg., 1980, 31, 39-43).

Pharmacodynamics of vecuronium and pancuronium in cats with and without ligated renal pedicles.

The pharmacodynamic behaviour upon continuous infusion and bolus administration of pancuronium and vecuronium was studied in cats with and without ligated renal pedicles. In all circumstances vecuronium had a shorter time course of action than pancuronium. Ligation of the renal pedicles, i.e. acute renal failure, did not significantly influence the time course of the respective neuromuscular blockades. It is suggested that uptake by aspecific binding sites of the compounds is the main determining factor in termination of the blockade. A difference between acute and chronic renal failure is expected to exist.

The comparative neuromuscular blocking effects of some aminoglycoside antibiotics.

The neuromuscular blocking effects of aminoglycoside antibiotics were tested in the isolated phrenic nervediaphragm preparation of the rat. The neuromuscular blocking potencies were netilmicin equals sisomicin much greater than neomycin much greater than gentamicin much greater than tobramycin. The EC 50's (concentration resulting in 50 percent depression of the original twitch tension) were respectively 13.3 x 10(-4); 13.4 x 10(-4); 13.6 x 10(-4); 15.1 x 10(-4); and 95.3 x 10(-4) Mol/l for netilmicin, sisomicin, neomycin, gentamicin and tobramycin. When a threshold dose of pancuronium was added to the bathing fluid the EC 50's were diminished respectively by a factor of 0.4 (sisomicin and neomycin) 0.5 (tobramycin) and 0.6 (netilmicin and gentamicin). Addition of a threshold dose of Org-NC45, a new steroidal non-depolarizing muscle relaxant, diminished the EC 50's to the same extent. The neuromuscular blocking effects of pancuronium and Org-NC45 themselves were potentiated by pretreatment of the preparations with a threshold dose of the aminoglycoside. Comparison of the results demonstrated the following potentiating effects: netilmicin equals sisomicin much greater than neomycin much greater than gentamicin greater than tobramycin. Which is in the same sequence s the neuromuscular blocking potencies of these drugs.