[Practice and complications of spinal anesthesia in African tropical countries]

OBJECTIVE

To evaluate the risk of the practice of spinal anaesthesia (SA) in African tropics.

STUDY DESIGN

Prospective study in multiple centres over a two years period.

PERSONS

Twenty-one anaesthesiologists and anaesthetist nurses covering ten African countries.

METHODS

Two anonymous questionnaires; the first, filled in each anaesthetic problem occurred, to define the type of incident or accident, and its circumstances; the second was designed to define the position occupied, to quantify the global anaesthetic activity, the number of SA, and to value the number of complications or deaths linked to SA.

RESULTS

Six anaesthesiologists and one anaesthetist nurse replied to the study, covering six sites in five different countries (Senegal, Chad, Central African Republic, Niger and Madagascar). On the 18,432 anaesthetic acts collected, 2,703 (14.7%) were SA. In the well-equipped centres, general anaesthesia was predominant with a frequency of over 75%. However in the not so well equipped centres or those which supplies were more problematical, SA technique was used with a frequency varying from 48.9 to 68.7%. Forty incidents and accidents were reported (1.5%), five led to the death of the patient (0.2%). Among the seven cardiac arrests (0.3%), four were fatal (0.1%). Eight of the ten accidents and all of the deaths occurred in the least equipped centres. Eight of ten accidents happened during emergency caesarean sections. All cardiac arrests were preceded by a severe hypovolemia. For the four deaths after cardiac arrest, an anaesthetist nurse with isobaric bupivacaine 0.5% carried out SA.

CONCLUSIONS

This study showed that the practice of SA in African tropics was performing in different practice conditions and people qualification than they were in France. The frequency of cardiac arrests and deaths was respectively five and 20 times more important, in those conditions. The first conclusion that can be drawn from this study is that it is questionable to use SA for emergency Caesarean section under hypovolemic condition. The second is the necessity for specific training on the local anaesthesia for anaesthetist nurses but also training to choose the anaesthesia best adapted to the surgery, the condition of the patient and the means available.

Hemodynamic aspects and oxygenation variables in severe malaria of adults in Africa

OBJECTIVES

Study of the hemodynamic profile and oxygenation variables in severe malaria to determine whether they are identical to those observed in severe bacterial infections.

DESIGN AND SETTING

Prospective study in an intensive care unit of a West African hospital.

PATIENTS AND PARTICIPANTS

Two groups of adult patients hospitalized for severe malaria according to WHO criteria, a control group (n = 13) with systemic vascular resistance of 800 dyne s(-1) cm(-5) or higher and a hyperkinetic group (n = 16) with a level lower than 800 dyne s(-1) cm(-5). Twenty-nine patients participated in this study (19 semi-immune, 10 nonimmune).

INTERVENTIONS

Before hemodynamic study a loading dose of quinine formiate was administered: 20 mg/ kg intravenously for 4 h. Artificial ventilation was used in the case of persistent hypoxemia.

MEASUREMENTS AND RESULTS

The hemodynamic study with Swan-Ganz catheter was performed after filling with 1,000 ml lactated Ringer's solution. From a clinical and a biological standpoint there was no difference between the two groups except for creatine phosphokinase, which was significantly higher in the hyperkinetic group: 2404 +/- 3654 vs. 1,898 +/- 1,828 IU/l. Hemodynamic and oxygenation variables showed a significant difference in cardiac index (6.1 +/- 1.2 vs. 3.9 +/- 1.21 min(-1) m(-2)), systemic vascular resistance (536 +/- 143 vs. 1098 +/- 170 dyne s(-1) cm(-5)), oxygen delivery (645 +/- 163 vs. 482 +/- 186 ml min(-1) m(-2)), and oxygen extraction (23 +/- 9 % vs. 34 +/- 14 %). Oxygen extraction was negatively correlated with oxygen delivery in the control group but not in the hyperkinetic group. Eight of 10 nonimmune patients (80 %) were in the hyperkinetic group versus 8 of 19 semi-immune patients (42 %; p < 0.05). Nine patients in the hyperkinetic group (69 %) and seven of the control group (46 %) died (NS).

CONCLUSIONS

In contrast to severe bacterial infections, severe malaria does not always induce hyperkinetic-type hemodynamic changes. Such changes are observed mostly in nonimmune subjects.

[Prognostic value of cytokines and HLA markers in patients with cerebral malaria in Senegal]

41 patients senegalese patients suffering from clinically defined severe malaria were studied in the intensive medical care unit of the Hôpital Principal in Dakar, Senegal. All of these individuals lived in Dakar, an area of low and seasonal Plasmodium falciparum transmission. In this study, we aim to determine in one hand, the cytokine levels of TNF-alpha, TNF-alpha sRI, TNF-alpha sRII, IL-2 sR, IL-6, IL-6 sR, and IL-10 to evaluate their prognostic value in the course of the disease; in the other hand, the influence of the HLA-DR alleles in the susceptibility to get severe malaria. At the day of admission (day 0) and 3 days later, one or two blood samples were collected for each patient to assess different biological parameters. Plasma samples were tested for cytokines cited above by ELISA (Medegenix EASIA kits) and DNA samples for HLA-DR by PCR-SSP genotyping. The concentrations of all the cytokines and/or their receptors were significantly increased at day 0 in the patients who died (TNF-alpha = 455 +/- 480 pg/ml, IL6 = 511 +/- 396 pg/ml) and decreased rapidly in the patients who survived from the disease (TNF-alpha = 354 +/- 629 pg/ml, IL6 = 453 +/- 706 pg/ml). A fatal issue seems likely related to the age of patients (20 +/- 12 years for surviving patients and 31 +/- 16 years for patients who died) and the kinetic of the cytokines. Significant differences were observed (pc < 0.001) between patients with severe malaria and a control group for the following HLA alleles: DR3, DR10 and DR13. The HLA-DR13 allele was found positively and highly associated with severe malaria.

[Closed-heart mitral commissurotomy: our experience at the Main Hospital in Dakar]

Confronted with difficulties of medical evacuation to cardiovascular surgical hospitals in Europe, the authors decided to bring up to date closed heart mitral commissurotomy. The aim of the study was to estimate possibility to select patients, to operate them safety to appreciate the results in medium and short time and the intervention's cost. 8 women and 7 men had a closed heart mitral commissurotomy from June 1995 to January 1997 in Dakar Principal Hospital; inclusion criteria were a symptomatic mitral stenosis with area less 1.5 cm2; exclusion criteria were an other valvulopathy, a Wilkin score above 8, a severe pulmonary arterial hypertension, an auricular thrombosis. One patient died on the forth day; a completely regressive hemiplegia was the only complication; 14 patients were clinically very improved: the average mitral area by planimetry form 0.89 cm2 +/- 0.15 became 1.64 cm2 +/- 0.33 and by Hatle formula from 0.82 cm2 +/- 0.12 to 1.71 cm2 +/- 0.37; the intervention cost was in second class 1,000,000 F CFA, in third class 820,000 F CFA. This study shows closed mitral commissurotomy can be realised in an african hospital as Dakar Principal Hospital; short and medium results are good; African surgeons must go on studying this surgical technic.

[Susceptibility to neuro-malaria and HLA-DR alleles in Senegal]

A prospective study was carried out in 46 patients suffering from severe malaria. The control group included 220 persons of which the HLA-DR distribution was known. The HLA-DRB1 alleles were typed by PCR-SSP (Sequence Specific Primers). The most frequent HLA-DR alleles found in patients group were: DR52 (82.8%), DR13 (57.1%), DR10 (28.6%), DR53 (25.7%), DR3 (20%), DR18 (20%). A significant difference was observed between patients with severe malaria and control group for the following alleles: DR3, DR10, DR13 (p < 0.001; Chi square with Yates' correction) and their relative risk were respectively 14.67; 6.29; 2.84. HLA-DR3 was considered as the major marker associated to severe malaria.

[Re-expansion pulmonary edema after excision of an intrathoracic tumor]

We report an acute respiratory insufficiency following the removal of a large intrathoracic fibroma (3.1 kg) in a 6 year-old child, caused by a re-expansion pulmonary oedema (unilateral oedema occurring within one hour after expansion). This oedema improved rapidly and was followed by a well-tolerated pleural effusion. This complication is due to discrepancy between a small lung and a large thoracic cavity, due to the prolonged time course of the tumor growth. These oedemas are caused by rapid lung re-expansion, the volume of the removed tumor and the depth of postoperative pleural suction. The value of positive-end expiratory pressure is discussed.

[Multiple organ failure syndrome after ovarian hyperstimulation]

Ovarian stimulation is used to treat female infertility, especially in Black Africa where infertility is considered as shameful. Ovarian stimulation can lead not only to multiple pregnancies but also to severe systemic complications such as the one described in this report. Ovarian stimulation using human menopausal gonadotropin led to ovarian hyperstimulation and multiple organ failure in a 28-year-old Senegalese woman. Symptomatic treatment using corticosteroids, abdominal paracentesis to relieve ascites, and fluid expansion failed. Bilateral ovariectomy was performed resulting in permanent sterility. Ovarian stimulation requires close monitoring by ultrasound visualization and measurement of 17 beta-estradiol to allow early detection of complications.

Prognostic value of anti-Plasmodium falciparum-specific immunoglobulin G3, cytokines, and their soluble receptors in West African patients with severe malaria

Forty-one African patients suffering from clinically defined severe malaria were studied in the intensive medical care unit of the main hospital in Dakar, Senegal, West Africa. All of these individuals lived in Greater Dakar, an area of low and seasonal Plasmodium falciparum endemicity. Twenty-seven patients (mean age +/- 1 standard deviation, 19.2 +/- 12.7 years) survived this life-threatening episode, but 14 (30.8 +/- 16.2 years old) died despite initiation of adequate treatment. On the day of admission (day 0) and 3 days later, one to two blood samples (i.e., approximately 10 to 15 ml) were obtained from each subject, and different biological parameters were evaluated in the two groups. Plasma samples were tested for their content in tumor necrosis factor alpha (TNF-alpha), soluble receptors I and II for TNF-alpha (TNF-alpha sRI and TNF-alpha sRII), interleukin-6 (IL-6), IL-6 sR, IL-10, and IL-2 sR. The concentrations of all these cytokines and/or their receptors was significantly elevated in patient plasma samples on day 0, and it rapidly decreased in the group of individuals who survived. By comparison, the mean concentration of the same parameters decreased slowly in the group of patients who died (except for IL-10, which dramatically fell in all patient plasma samples soon after initiation of antimalarial treatment). The TNF-alpha sRI level remained significantly elevated among the patients who died, and the highest levels of soluble TNF-alpha sRI receptor were found among the older patients. Parasite-specific immunoglobulin M (IgM), total IgG, IgG1, IgG2, IgG3, and IgG4 were evaluated by enzyme-linked immunosorbent assay using a crude extract of a local P. falciparum isolate as antigen and human class- and subclass-specific monoclonal antibodies. Parasite-specific IgM, total IgG, and IgG1 were detectable in the plasma samples of most of these African patients, whereas IgG2 and IgG4 mean values were low. The mean level of parasite-specific IgG3 was different (P = 0.024) at day 0, i.e., before initiation of intensive medical care, between the group of the 27 surviving subjects and the group of 14 patients dying of severe malaria. As a consequence, most of the African patients who died had only trace amounts or almost no detectable level of parasite-specific IgG3 at the time of admission. In contrast, the presence of even limited IgG3 activity at day 0 was found to be associated with a significantly increased probability of recovering from severe malaria. Therefore, in our study, both an elevated level of TNF-alpha sRI and absence of IgG3 activity were of bleak prognostic significance, whereas a favorable outcome was usually observed when parasite-specific IgG3 activity was detectable. This finding was strongly suggestive of a prime role for these parasite-specific immunoglobulins in the capacity to help recovery from severe malaria.

Therapeutic trial of diazepam versus placebo in acute chloroquine intoxications of moderate gravity

OBJECTIVE

Acute chloroquine intoxication is responsible for a membrane-stabilising effect which results in electrocardiographic (ECG) and hemodynamic disturbances. Diazepam is used in acute chloroquine intoxication on the basis of clinical and experimental observations, but its utility alone, in man, remains unproven. The goal of this study was to verify whether diazepam alone has an effect on the membrane-stabilising effect observed in moderately severe chloroquine intoxications.

DESIGN

Prospective, multi-center, double-blind, placebo-controlled study.

SETTING

Prehospital mobile intensive care units (Paris) and hospital intensive care units (paris and Dakar).

PATIENTS AND PARTICIPANTS

Adults with moderately severe intoxication defined as: a suspected ingested dose of 2 or more but less than 4 g, systolic blood pressure (SBP) higher than 80 mmHg, QRS duration less than 0.12 s and the absence of dysrhythmia at inclusion.

INTERVENTIONS

Patients received either a loading dose of 0.5 mg/kg diazepam followed by an infusion of 1 mg/kg over 24 h or an equivalent volume of placebo.

MEASUREMENTS AND RESULTS

Outcome was measured by serial assessments of SBP, ECG (QRS and QT segments) and clinical deterioration. There were no significant differences observed in the initial or serial ECG or SBP measurements. There were no deaths and no patient had to be removed from the study due to clinical deterioration.

CONCLUSIONS

Diazepam, at the dose studied, does not appear to reverse the chloroquine-induced membrane-stabilising effect in acute moderately severe chloroquine intoxication. Supportive intensive care of these intoxications appears to be all that is necessary.

Extensive genetic diversity of Plasmodium falciparum isolates collected from patients with severe malaria in Dakar, Senegal

While some genetic host factors are known to protect against severe Plasmodium falciparum malaria, little is known about parasite virulence factors. We have compared the genetic characteristics of P. falciparum isolates collected from 56 severe malaria patients and from 30 mild malaria patients recruited in Hôpital Principal, Dakar, Senegal. All isolates were typed using polymerase chain reaction amplification of polymorphic genetic loci (MSP-1, MSP-2, HRP1, GLURP, CSP, RESA, and the multigene family Pf60). The complexity of infections was lower in severe than in mild malaria and the parasite genetic diversity in both groups was very large. No specific genetic make-up was associated with severity; there were, however, marked differences in allele frequencies in both groups, with a prevalence up to 60% of MSP-2 alleles specifically observed in the severe malaria isolates. In addition, the presence of MSP-1/RO33 alleles was significantly associated with a higher plasma level of tumour necrosis factor alpha receptor 1 (P < 0.05), a reported indicator of severity in human malaria. These results point to potential differences in the genetic characteristics of parasites inducing severe versus mild pathology.

[Fatal poisoning caused by African viper's bite (Echis carinatus)]

The case is reported of a 44-year-old European who was bitten on the foot in Djibouti, probably by an African viper. Unusually, there wasn't any pain, nor any cardiovascular collapse nor any local swelling. An oedema of the lower limb started the day afterwards. Two days after the bite, the patient presented a generalized haemorrhagic syndrome, which led to his admission. There was a consumption of fibrinogen and prothrombin, without any decrease in the platelet count. Heparin was started (100 IU.kg-1.day-1), as well as fluid replacement (albumin, fresh frozen plasma, packed red cells). This allowed him to be transferred to France, where he arrived in anuria, with hyperpyrexia, and severe lower limb oedema and a haemorrhagic syndrome. There was a major extensive retroperitoneal haematoma spreading to the perineum. The four limbs were ischaemic. The patient's condition continued to worsen, developing hypoxic pulmonary oedema. He died on the seventh day after the bite, during a session of haemodialysis, from cardiovascular failure resistant to all the usual drugs. The principles of anti-venom therapy are recalled. Indeed, this should be started early enough and relies on large amounts of serum (greater than 50 ml).

[A deep skin burn caused by the local application of a traditional oily ointment of Senegal (Carapa procera)]

Many traditional ointments are utilized in Senegal because of their local effects. We report the case of a new born girl deeply burned by the application of "Touloucouna" (Carapa Procera) on her skin. The berries of the tree contain cyclic terpens (Meliacine) well known for inducing inflammation by contact with the skin. They are most likely responsible for that burn until now, such injuries have never been described with Touloucouna.

Generation of intense 25-fsec pulses by a pulsed laser system

A pulsed femtosecond dye laser is demonstrated with relaxed stability requirements, improved output reproducibility, and significant pulse shortening. Starting with a sequence of approximately 350 pump pulses of a Nd:glass laser (repetition rate 6 Hz, duration 1.3 psec), pulses of 25 fsec and 10 nJ are generated at 566 nm. A non-colliding-pulse, mode locked ring laser is used with dispersion compensation and the dyes Rhodamine 6G, DQOCI, and DTCI. The evolution of the pulse parameters as a function of cavity round trips is investigated.

Interferometric evaluation of collagen concentration in tendon fibers

The dry mass concentration of collagen in native rat tail tendon fibers was studied by interferometric techniques. It could be shown that the collagen concentration of rat tail tendon fibers is not constant nor does it vary uniformly with the fiber diameter. Evidence is presented that the collagen concentration shows significant oscillations as a function of diameter. In order to explain the experimental findings, a layered model is proposed for the fiber structure; age dependent changes were also studied. It seems that the fiber structure is unaltered by ageing at the supramolecular level but its functional capacities are affected and swelling is inhibited.