Pattern of Right Ventricular Changes in Patients with Uncomplicated Systemic Hypertension at a Tertiary Centre in Southwest Nigeria.

BACKGROUND AND AIMS: Hypertension is an independent risk factor for cardiovascular complications. The effect of systemic hypertension on the right ventricle (RV) has received less attention probably due to its complex structure and location. The aim of the study was to assess the effect of systemic hypertension on the structure and function of the right ventricle using transthoracic echocardiography. METHOD: One hundred hypertensives and 100 healthy controls were recruited into the study. Transthoracic echocardiography was used to measure RV wall thickness (RVWT) in diastole, RV internal dimensions in diastole, tricuspid annular plane systolic excursion (TAPSE), right ventricular filling velocities (TE and TA), and RV systolic excursion velocity (RVSm). These measurements were repeated on the left ventricle. RESULTS: There was significantly thicker RV wall (0.51 + 0.08cm vs 0.44+0.08cm; p=0.001) in the hypertensive group and higher frequency of RV hypertrophy (48.45% vs 18.75%; p<0.001). Tricuspid annular plane systolic excursion (TAPSE) and the tricuspid annular peak systolic excursion velocity (TSm) were significantly lower in the hypertensive group (2.34+0.45cm vs 2.50+0.36cm; p=0.008, and 11.70+3.03cm/s vs 12.60+2.93cm/s p=0.039, respectively), though no participant had abnormal TAPSE. Tricuspid E/A ratio was lower in the hypertensive group (1.13+ 0.33 vs 1.24+0.27; p=0.011). The tricuspid E/A ratio had positive correlation with mitral E/A ratio. CONCLUSION: Right ventricular structural and functional changes are found in systemic hypertension, even in the absence of other systemic complications. These changes could have been mediated by ventricular interdependence and altered humoral factors.

CONTEXTES ET OBJECTIFS: L'hypertension artérielle est un facteur de risque indépendant pour les complications cardiovasculaires. L'effet de l'hypertension artérielle systémique sur le ventricule droit (VD) a reçu moins d'attention probablement en raison de sa structure complexe et de son emplacement. L'objectif de l'étude était d'évaluer l'effet de l'hypertension artérielle systémique sur la structure et la fonction du ventricule droit en utilisant l'échocardiographie transthoracique. MÉTHODE: Cent hypertendus et 100 témoins en bonne santé ont été recrutés dans l'étude. L'échocardiographie transthoracique a été utilisée pour mesurer l'épaisseur de la paroi du VD (EPVD) en diastole, les dimensions internes du VD en diastole, l'excursion plane systolique annulaire tricuspide (TAPSE), les vitesses de remplissage ventriculaire droit (TE et TA), et la vitesse d'excursion systolique ventriculaire droit (RVSm). Ces mesures ont été répétées sur le ventricule gauche. RÉSULTATS: Il y avait une paroi du VD significativement plus épaisse (0,51 ± 0,08 cm vs 0,44 ± 0,08 cm ; p=0,001) dans le groupe hypertendu et une fréquence plus élevée d'hypertrophie ventriculaire droite (48,45% vs 18,75% ; p<0,001). L'excursion plane systolique annulaire tricuspide (TAPSE) et la vitesse maximale systolique annulaire tricuspide (TSm) étaient significativement plus basses dans le groupe hypertendu (2,34 ± 0,45 cm vs 2,50 ± 0,36 cm ; p=0,008, et 11,70 ± 3,03 cm/s vs 12,60 ± 2,93 cm/s p=0,039, respectivement), bien qu'aucun participant n'ait eu de TAPSE anormal. Le rapport E/A tricuspide était plus bas dans le groupe hypertendu (1,13 ± 0,33 vs 1,24 ± 0,27 ; p=0,011). Le rapport E/A tricuspide avait une corrélation positive avec le rapport E/A mitral. CONCLUSION: Des modifications structurales et fonctionnelles du ventricule droit sont retrouvées dans l'hypertension artérielle systémique, même en l'absence d'autres complications systémiques. Ces changements pourraient avoir été médiés par l'interdépendance ventriculaire et des facteurs humoraux modifiés. MOTS-CLÉS: Hypertension ; Échocardiographie ; Hypertrophie ventriculaire droite ; Dysfonction diastolique ventriculaire droit.

Clinical and echocardiographic correlates of pulmonary hypertension among heart failure patients in Lagos, south-western Nigeria.

BACKGROUND: Pulmonary hypertension (PH) is very prevalent among heart failure (HF) subjects and is now recognised as an independent predictor of poor prognosis. There is a paucity of data in our environment about the frequency and correlates of PH in HF. We aimed to determine the frequency of PH in HF patients in an academic hospital and assess its correlates using echocardiography. METHODS: A total of 219 heart failure patients in NYHA functional class II to IV, and without co-morbidities that could cause PH, were consecutively recruited. Demographic, clinical and echocardiographic data were obtained from all subjects. RESULTS: The frequency of PH was 38.8%, using an estimated pulmonary artery systolic pressure (PASP) cut-off value of > 36 mmHg. HF subjects with PH tended to be male with a worse NYHA functional class compared with subjects without PH. HF subjects with PH also had significantly higher left ventricular (LV) filling pressures (higher left atrial volume index and E/e' ratio), more severe mitral regurgitation (MR), poorer LV systolic function, and worse parameters of right ventricular (RV) structure and function compared with those without PH. Echocardiographic variables that correlated significantly with PASP include LV filling pressures (p < 0.001 for all), mitral regurgitant volume (r = 0.269, p < 0.001) and LV ejection fraction (r = -0.239, p > 0.001). On multivariate analysis, the left atrial volume index and E/e' ratio were independently associated with PASP. CONCLUSIONS: PH is common among HF subjects in our environment and is associated with higher LV filling pressure, more severe MR, poorer LV systolic function and worse RV remodelling. Routine screening for PH among HF patients is recommended for better risk stratification and management.

Routine hemoglobin electrophoresis for pediatric surgery day case in at-risk populations: Suggested algorithm for screening using clinical risk factors.

BACKGROUND: Hemoglobin electrophoresis (HBE) is a part of the preoperative routine requested by anesthetists. However, the prevalence of hemoglobinopathy in the population is low. This study aims to determine the clinical risk factors for hemoglobinopathies and propose clinical guidelines for preoperative screening of patients for pediatric day care surgery. PATIENTS AND METHODS: A prospective study carried out over 12 months. Consecutive patients aged 6 months and older who had day case surgery were recruited to the study. Biodata and relevant clinical data were collated and documented in a proforma and analyzed using a statistical package for social sciences version 17. RESULTS: There were 124 patients106 boys and 18 girls. The median age was 3 years. Scrotal lesions were the most common conditions managed (71.7%). Seventy-eight percent of patients had HbAA, 15.3% had HbAS, and 4.8% had HbAC while 0.8% each had both HbSC and HbSS. At least one parent of 78.2% knew their Hb phenotype, of which, 79% were HbAA. A history of jaundice (P = 0.0001), hand and foot syndrome (P = 0.0001), frontal bossing (P = 0.0001), and low packed cell volume at surgery (P = 0.001) were found significant in predicting hemoglobinopathies. There was no mortality. CONCLUSION: Risk factors for hemoglobinopathies from this study included a positive history of jaundice, hand and foot syndrome, frontal bossing, and anemia. Proposed guidelines for HBE screening include the presence of hemoglobinopathy in one parent if one parent has sickle cell trait, and the other parent's genotype is unknown or if any of the risk factors is present.

Low-dose intravenous ketamine improves postoperative analgesia after caesarean delivery with spinal bupivacaine in African parturients.

BACKGROUND: In the absence of neuraxial opiates, postoperative analgesia after caesarean delivery is limited by the duration of action of bupivacaine. This could be prolonged by the co-administration of adjuvants such as ketamine. METHODS: Spinal anaesthesia was performed in 60 parturients using hyperbaric bupivacaine 15 mg. Patients were randomly allocated to receive a 2-mL intravenous injection of either ketamine 0.15 mg/kg (Group BK) or 0.9% saline (Group B) immediately after institution of spinal anaesthesia. Postoperative pain was assessed using a visual analogue scale and the time of first postoperative analgesic administration was noted. Postoperative analgesia was provided with intramuscular pentazocine and diclofenac, the total doses of which were recorded over 48 h. RESULTS: The mean (SEM) time of first postoperative analgesic administration was significantly longer in Group BK (209±14.7 min) than in Group B (164±14.1 min) (P<0.001). Pain scores were significantly lower in Group BK than in Group B for 120 min after surgery (P=0.022). Patients in Group BK required significantly less diclofenac (P<0.001) and pentazocine (P<0.001) on day one after surgery. There was no difference in diclofenac (P=0.302) and pentazocine (P=0.092) consumption between the groups on the second postoperative day. The incidence of adverse effects was not different between the groups. CONCLUSION: The use of intravenous low-dose ketamine as an adjuvant to bupivacaine for spinal anaesthesia for caesarean delivery was associated with longer postoperative analgesia and lower early postoperative analgesia consumption than bupivacaine alone.

Propofol versus halothane in paediatric daycase surgery: a comparison of the duration of induction and haemodynamic profile.

BACKGROUND: Inhalational induction with Halothane is commonly used for anaesthesia in children. Its drawbacks include bradycardia and hypotension. Intravenous propofol has recently challenged this position. OBJECTIVE: This study sought to compare duration of and cardiovascular changes at induction of anaesthesia in children. METHODS: Sixty ASA I and II children aged 1- 7 years scheduled for elective daycase surgery were prospectively studied from January to July 2008. They were assigned to receive inhalational induction with halothane 3% or intravenous induction with 3.5mg/kg of propofol. Heart rate, systolic, diastolic and mean blood pressure as well as oxygen saturation were monitored throughout induction. The duration of induction as well as any complications were documented. RESULTS: Demographic data was comparable between the two groups. Duration of induction was significantly longer in the halothane group 8.23 +/- 2.34 minutes compared with 2.30 +/- 1.26 minutes in the propofol group (p < 0.001). Heart rate rose by 4.7 +/- 17.73 beats/minute in the propofol group and fell by 4.19 +/- 18.03 in the halothane group (p = 0.05). Systolic, diastolic and mean blood pressures fell in both groups with values being less in the halothane group. These differences were not significantly different (p = 0.189, p = 0.059, p = 0.058 respectively). Sixteen patients (33%) in the propofol group developed apnoea compared to 2 (6.6%) in the halothane group (p < 0.001). The duration of apnoea differed significantly between groups (p = 0.003). CONCLUSION: Halothane and propofol had similar changes to cardiovascular parameters during anaesthetic induction. The shorter duration of induction of propofol may be preferable for daycase surgeries.

Intraocular pressure changes in a Nigerian population--effects of tracheal tube and laryngeal mask airway insertion and removal.

OBJECTIVES: Laryngoscopy and tracheal intubation lead to acute elevation in intraocular pressure (IOP); the ocular hypertensive response. The Laryngeal mask airway prevents sudden surges in IOP. We compared IOP changes to the insertion and removal of the Laryngeal mask airway (LMA) and the endotracheal tube (ETT). PATIENTS AND METHODS: Seventy ASA I and II patients aged 18 to 60 years at the Lagos University Teaching Hospital between January and December 2003 were randomly allocated to receive either an LMA or ETT for airway management. Anaesthesia was induced with propofol and atracurium. Intraocular pressure was measured by applanation tonometry post induction (baseline) and prior to removal (pre-extubation), after insertion or removal (0 minute), at 1,2,3,5 and 10 minutes after insertion or removal. RESULTS: Insertion of the airway device caused an immediate rise in IOP of 4.6% in the LMA group (from 13.1 +/- 2.4 to 13.7 +/- 2.4 mmHg) and 49.2 in the ETT group (from 12.0 +/- 2.5 to 17.9 +/- 4.0 mmHg) (p<0.001). Removal of the airway device caused an immediate rise in IOP of 14.6 in the LMA group (from 11.26 +/- 2.4 to 12.9 +/-2.4 mmHg) and 50.3 in the ETT group (from 11.37 +/- 2.0 to 17.1 +/- 3.3 mmHg) (p<0.001). IOP thereafter declined towards baseline in both groups. Cardiovascular responses accompanied IOP changes. The mean insertion time was 39.8 +/- 9.1 seconds (ETT) vs 31.5 +/- 4.4 seconds (LMA). (p<0.001) Cough (17.1) and mild laryngeal spasm (2.9) occurred in the ETT group only following removal. CONCLUSION: The LMA produced better IOP stability following its insertion and removal compared to the tracheal tube.

Appropriateness of intra-operative blood transfusion in children at the Lagos University Teaching Hospital--an initial survey.

BACKGROUND: The decision to transfuse intra-operatively is based on preoperative haemoglobin (Hb), estimated blood loss and physiological variables. The visual estimate of blood loss is notoriously unreliable especially with small volumes of blood losses in children. OBJECTIVES: We sought therefore to determine the appropriateness of intra-operative blood transfusion in a sample of children METHODS: All children requiring intra-operative blood transfusion between May and June 2008 were prospectively studied. Neonates and children already on blood transfusion at induction were excluded. Transfusion was prescribed at the discretion of the attending anaesthetist. The Estimated blood volume (EBV) and estimated blood loss (EBL)were determined. Appropriate transfusion was defined as blood transfusion at EBL > 15% of EBV, maximum allowable blood loss to PCV of 27% and pre-transfusion Hb < 8g/dl. RESULTS: Twenty-five patients were studied with a mean age of 4.16 +/- 3.59 years (Range 0.33-11 years). The mean preoperative PCV was 31.14 +/- 3.53% (range 25-34%). Twelve patients (48%) were appropriately transfused when MABL was calculated to PCV of 27%. Nine patients (36%) had appropriate blood transfusion at an EBL greater or equal to 15% of the EBV. Of the 12 patients that had pre-transfusion Hb measured, 2 (16.6%) were appropriately transfused at Hb < 8 g/dl. CONCLUSION: The use of near patient monitoring devices should be encouraged as this will give an accurate assessment of Hb and appropriate indication for transfusion. Equipment should be made available to perform gravimetric estimation of blood loss as the visual method is notoriously unreliable.

Transfusion trigger--how precise are we? Intraoperative blood transfusion practices in a tertiary centre in Nigeria.

SUMMARY: To determine how well anaesthetists in Nigeria determine the need for transfusion based solely on physiological variables and estimated blood loss. To determine the incidence of inappropriate blood transfusion. Anaesthetists in our hospital determine when to transfuse patients based solely on clinical acumen. This may result in inappropriate transfusion especially in this subregion where blood donors are scarce and risk of transmission of infection high. All surgical patients requiring blood transfusion were prospectively studied over 3 months. Transfusion was based solely on the discretion of the attending anaesthetist. Haemoglobin (Hb) concentration was measured prior to transfusion and 24 h postoperatively. Appropriate transfusion was defined as blood transfusion at Hb < 8 g dL(-1) or 10 g dL(-1) in the elderly and those with medical comorbidities. The trigger for transfusion was documented as well as estimated blood loss. Thirty-four patients were studied. The mean pretransfusion Hb was 8.09 +/- 2.45 g dL(-1) (range 4.6-14.2). Twenty-one patients (61.8%) had appropriate blood transfusion. The commonest transfusion triggers were clinical pallor (82.4%), excessive blood loss (76.4%), delayed capillary refill (55.9%) and severe hypotension (50%). The use of near patient monitoring devices might further improve blood transfusion practice in this setting where donor blood is scarce.

Pre-induction hypokalaemic phenomenon in Nigerian adult population.

BACKGROUND: Anaesthesia in the perioperative period is characterized by acute changes in plasma potassium (K+) which may be caused by anxiety. Anxiety leads to an intracellular shift of potassium which may lead to hypokalaemia. These fluctuations in plasma potassium may sometimes induce arrhythmias. This study was designed to determine the acute changes in plasma potassium levels in the immediate pre-induction period in a sample of Nigerian patients and to determine the incidence of arrhythmias correlating with these changes. METHODS: Sixty ASA I and II adults aged 14 to 70 years, both genders, undergoing elective surgery under general anaesthesia at the Lagos University Teaching Hospital were prospectively and consecutively recruited. Preoperative plasma potassium level was determined 1-3 days before surgery. Premedication was with oral diazepam 10-20 mg given nocte and on the morning of surgery. Pre-induction plasma potassium level was determined within 5 minutes before induction of anaesthesia. RESULTS: Mean preoperative K+ was 3.98 +/- 0.38 mEq.L(-1) (range of 3.5 - 4.9 mEqL(-1)). The mean pre-induction plasma K+ level was 3.01 +/- 0.35 mEq.L(-1) (range of 2.1 - 3.6). This represented a fall of 24% (0.97 +/- 0.39 mEq.L(-1)) which was significantly different (p < 0.001). More than 80% of the patients exhibited some fall in plasma K+. No arrhythmias were recorded during the study period. CONCLUSION: Pre-induction hypokalaemia occurred frequently despite the administration of anxiolysis with diazepam. There is a need to consider this phenomenon and measure K+ levels immediately pre-induction especially in patients with existing borderline normal K+ levels.

Post operative nausea and vomiting in adult Nigerians.

BACKGROUND: This is a prospective study to determine the pattern of postoperative nausea and vomiting in a Nigerian adult population. METHOD: 348 consecutive patients were assessed prospectively for the incidence and risk factors of postoperative nausea and vomiting over a 6-month period. The exclusion criteria included inability to give consent, nausea or vomiting during the period 24 hours before surgery, raised intracranial pressure and patients who received an anti-emetic in the period 48 hours before surgery. RESULT: Patient's age ranged between 18 and 90 years. There were 213 females (61.2%) and 135 males (38.8%). The incidence of postoperative nausea was 32.2% and vomiting was 20.1%. The major risk factors identified were female gender, body mass index, general anaesthesia-inhalational technique, Ketamine induction, pancuronium, pain and movement of patients from the recovery room to surgical wards (p < 0.05). CONCLUSION: Nausea and vomiting was identified as a common postoperative complication with multifactoral aetiology. It is recommended that high risk patients should receive prophylactic antiemetics. Regional techniques should also be considered in such patients.

Antiemetic prophylaxis with promethazine or ondansetron in major gynaecological surgery

Background: Postoperative nausea and vomiting remain a significant cause of morbidity among patients undergoing general anaesthesia. The optimal strategy for prevention; however; remains controversial. This study evaluated the efficacy of ondansetron 8 mg compared with promethazine 25 mg or placebo for the prevention of nausea and vomiting in patients undergoing elective major gynaecological surgery. Methods: Seventy-five patients received intravenous injection of the study medication (ondansetron-25; promethazine-25 or placebo-25) immediately before the induction of anaesthesia. Nausea and vomiting were assessed over a 24-hour postoperative period. Results: Nausea occurred in 20; 40and 72of the promethazine; ondansetron and placebo groups respectively (p = 0.001). The overall incidence of vomiting was 12; 16; and 60(p = 0.000) for promethazine; ondansetron and the placebo respectively. Postoperative drowsiness was prominent in the promethazine group. There was no significant difference in effectiveness between promethazine and ondansetron. Conclusions: Promethazine 25 mg was significantly more effective than ondansetron 8 mg in the prevention of postoperative nausea and vomiting. Promethazine is inexpensive and the cost of drugs is of importance in developing African countries. Drowsiness was a significant side-effect with promethazine; and this will be a disadvantage in ambulatory surgery

An audit of perioperative cardiac arrest at Lagos University Teaching Hospital.

OBJECTIVE: Intraoperative cardiac arrests are not uncommon and are related to both surgical and anaesthetic factors. This study aimed to examine the factors which predispose to a periopeartive cardiac arrest, to assess the appropriateness of therapy and the outcome. MATERIALS AND METHODS: All perioperative cardiac arrests in adults that occurred in a one year period(January 2003 to December 2003) at the Lagos University Teaching Hospital were prospectively studied. All patients less than 16 years and cardiac arrests occurring outside the direct supervision of the anaesthetists were excluded. Study variables included demographic data, ASA score, urgency of surgery, surgical procedure, aetiology, time and duration of arrest, cardiac arrest rhythm, management as well as immediate outcome and survival to hospital discharge. RESULTS: Thirteen cardiac arrests occurred in 2147 cases (incidence of 6 per 1000). The mean age of patients was 30.23 +/- 11.06 years. Ten patients had anASA score greater than 3. Hypovolaemia was responsible for arrests in 9 patients. Two arrests occurred at induction, 7 intraoperatively and 4 postoperatively. Seven patients had non-VF/VT rhythms. Cardiopulmonary resuscitation was instituted immediately. The mean duration of arrest was 25.66 +/- 13.34 minutes. Drug and defibrillator therapy were inadequate. Immediate survival occurred in 5 patients (38.46%). Factors associated with significant difference in recovery from a cardiac arrest were type of surgery (p=0.043) and duration of resuscitation (p=0.022) CONCLUSION: Majority of cardiac arrests were due to hypovolaemia from massive blood loss. There is a need for the provision of adequate banked blood as well as improvement in training in the management of in-hospital cardiac arrest to ensure a better outcome.

Knowledge, attitude and practices of Nigerian anaesthetists in HIV infected surgical patients- a survey.

In the light of increasing prevalence of the human immunodeficiency virus (HIV), anaesthetists are likely to see more patients with this virus in their practice. This study evaluated, using a questionnaire format, the knowledge, attitude and practices of anaesthetists in the management of HIV infected surgical patients. The questionnaire sought demographic information, the knowledge of risks involved as well as attitude and practices. One hundred (66.7%) out of 150 questionnaires distributed amongst members of the Nigerian Society of Anaesthetists were completed and returned. Fifty-five per cent (55%) of the respondents confirmed their willingness to be screened but only 45% had had a personal HIV screening test. Even though 23% of all the respondents will transfuse unscreened blood in an emergency, only 1(8.3%) of the consultants will do so. This trend was also reflected in gloving behaviour as 11(91.6%) of consultants will routinely wear gloves whilst only 12(70.5%) of the senior house officers will routinely glove for venepuncture despite the availability of gloves. Other precautionary facilities such as goggles, sharp disposal bins, routine screening of all surgical patients were more available in private than in government hospitals. Ninety- six per-cent of all respondents will initiate an action after a needle stick injury whilst 4% will ignore. General Anaesthesia was the choice of anaesthetic in an HIV/AIDS infected patient by 43% of respondents whilst 22% of respondents would choose regional technique. However, only 85% of respondents were willing to anaesthetise an infected patient. This study suggested a dearth of knowledge and perception of risks of HIV/AIDs amongst Nigerian Anaesthetists. Appropriate training and greater education is highly recommended. Rigorous infection control policy is imperative and hospital authorities must ensure availability of protective facilities.

Comparison of suxamethonium and priming with atracurium for rapid sequence orotracheal intubation in a Nigerian adult population.

OBJECTIVE: To compare suxamethonium with atracurium using the priming principle, for rapid sequence orotracheal intubation assessing onset time, time to successful laryngoscopy and intubation and quality of intubating conditions. PATIENTS AND METHODS: A prospective double-blind, randomised study was performed in 90 ASA physical status I and II patients aged between 18 and 64 years undergoing elective surgery requiring endotracheal intubation between October 2002 and June 2003 in a university teaching hospital . All patients were premedicated with 5-10mg oral diazepam and randomly assigned to one of two groups to receive either suxamethonium as a bolus dose (group A) or atracurium (priming with 0.05 mg/kg followed by 0.55 mg/kg after induction of anaesthesia) (group B). In both groups, the trachea was intubated when there was maximal muscle relaxation, determined clinically by jaw muscle relaxation. Muscle paralysis using a PNS, quality of intubating conditions, and occurrence of muscle weakness due to the priming dose of atracurium, time to laryngoscopy and onset time were all noted. RESULTS: Onset time was 87.1 +/- 25.60s and 135.8 +/- 46.23s in groups A and B respectively (P < 0.05). Group A had a laryngoscopy time of 73.6 +/- 25.22s compared to 107.7 +/- 41.32s in group B (P < 0.05). Intubating conditions were significantly better in group A compared to group B (P < 0.05). The frequency of muscle weakness from the priming dose of atracurium was 6.6%. CONCLUSION: Atracurium, using the priming principle, is an option in our environment for modified rapid sequence induction when suxamethonium is contraindicated.

Knowledge, attitude and practices of Nigerian anaesthetists in HIV infected surgical patients: a survey.

In the light of increasing prevalence of the human immunodeficiency virus (HIV), anaesthetists are likely to see more patients with this virus in their practice. This study evaluated, using a questionnaire format, the knowledge, attitude and practices of anaesthetists in the management of HIV infected surgical patients. The questionnaire sought demographic information, the knowledge of risks involved as well as attitude and practices. One hundred (66.7%) out of 150 questionnaires distributed amongst members of the Nigerian Society of Anaesthetists were completed and returned. Fifty-five per cent (55%) of the respondents confirmed their willingness to be screened but only 45% had had a personal HIV screening test. Even though 23% of all the respondents will transfuse unscreened blood in an emergency, only 1(8.3%) of the consultants will do so. This trend was also reflected in gloving behaviour as 11(91.6%) of consultants will routinely wear gloves whilst only 12(70.5%) of the senior house officers will routinely glove for venepuncture despite the availability of gloves. Other precautionary facilities such as goggles, sharp disposal bins, routine screening of all surgical patients were more available in private than in government hospitals. Ninety- six per-cent of all respondents will initiate an action after a needle stick injury whilst 4% will ignore. General Anaesthesia was the choice of anaesthetic in an HIV/AIDS infected patient by 43% of respondents whilst 22% of respondents would choose regional technique. However, only 85% of respondents were willing to anaesthetise an infected patient. This study suggested a dearth of knowledge and perception of risks of HIV/AIDs amongst Nigerian Anaesthetists. Appropriate training and greater education is highly recommended. Rigorous infection control policy is imperative and hospital authorities must ensure availability of protective facilities.

Is ephedrine infusion more effective at preventing hypotension than traditional prehydration during spinal anaesthesia for caesarean section in African parturients?

BACKGROUND: Hypotension following spinal anaesthesia for caesarean section may result in maternal nausea and vomiting and decreased uteroplacental blood flow with possible fetal acidaemia. Numerous methods have been tried to minimise hypotension. In developing countries where resources are limited, this study aimed to compare a standard infusion of ephedrine with traditional prehydration to prevent spinal hypotension. METHOD: Sixty patients for elective caesarean section were randomly allocated to group 1: 1 L 0.9% saline before spinal block, and group 2: infusion of ephedrine 30 mg in 1 L of 0.9% saline after spinal block, titrated to maternal systolic pressure. Spinal anaesthesia was achieved with 2.5 mL of 0.5% heavy bupivacaine in the L3/L4 interspace. RESULTS: Systolic pressure decreased 5 min after spinal block. Group 2 had higher mean values of systolic pressure throughout most of the study period than group 1 (P < 0.05). Hypotension occurred in 70% of patients in group 1 and 40% of patients in group 2 (P = 0.037). Severe hypotension occurred in 40% of group 1 and 13.3% of group 2 (P = 0.039). Nausea was the most common side effect of hypotension, occurring in 39.4% of all hypotensive patients. Other complications, including hypertension, tachycardia and bradycardia were similar in the two groups. Neonatal outcome was similar in the two groups and median Apgar scores at one and five minutes were 8. CONCLUSION: Prophylactic ephedrine given by standard infusion set was more effective than crystalloid prehydration in the prevention of hypotension during spinal anaesthesia for elective caesarean section.

A comparative study of the haemodynamic effects of atropine and glycopyrrolate at induction of anaesthesia in children.

BACKGROUND: Bradycardia following administration of halothane and suxamethonium in children leads to reduced cardiac output, which can be prevented with prophylactic anticholinergics. Anticholinergics may result in tachycardia and arrhythmias. This study was designed to compare haemodynamic changes and incidence of cardiac arrhythmias following intravenous atropine and glycopyrrolate. STUDY DESIGN: Ninety ASA I and II children between one month and twelve years were studied. Premedication was with oral promethazine 1mg/kg. Anaesthesia was achieved with 3 % halothane in 33 % oxygen and nitrous oxide. Patients were randomly allocated to receive atropine 0.01mg/kg (Group I) or glycopyrrolate 0.005mg/kg (Group II). Tracheal intubation was facilitated with suxamethonium 1.5mg/kg. RESULTS: Patients in Group I had a 35.7% rise in heart rate from baseline, compared to 22.5 % in Group II two minutes after anticholinergic administration (p=0.001). Following intubation, heart rate rose by 9.7 % and 13.2 % (p<0.05) in Groups I and II respectively. MAP rose similarly in both groups. Arrhythmia occurred in 44.4 % of patients in Group I and 11.1% in Group II (p=0.001) and were mainly sinus tachycardia. 2.2% of patients in Group I exhibited bigemini. No patient experienced bradycardia. Hypoxia occurred in 2.2 %, hypotension in 13.3% and mild laryngeal spasm in 0% of Group I and 11.1%, 4.4% and 4.4% of Group II respectively. CONCLUSION: The use of glycopyrrolate compared to atropine, offered better cardiovascular stability in Nigerian children. Arrhythmias occurred more in patients who had atropine and occurred most frequently after tracheal intubation.

Cardiovascular changes during halothane induction in children.

OBJECTIVES: The incidence of bradycardia and myocardial depression following halothane induction in children is well documented. Bradycardia leads to reduced cardiac output, which can result in compromised organ perfusion. Halothane may sometimes induce arrhythmia. There is at present no study in this sub-region on the cardiovascular changes of halothane induction in children. This study was designed to investigate the cardiovascular changes and incidence of arrhythmias following halothane induction. PATIENTS AND METHODS: Ninety ASA I - II children aged 6 months to 12 years were studied. Premedication with oral promethazine 1mg/kg was given to all patients above the age of one year. Anaesthesia was achieved with incremental halothane up to 3% in 33% oxygen and nitrous oxide. Halothane induction led to a significant drop in SBP, DBP and MAP in all patients at the end of induction. (p < 0.005). Heart rate values were significantly less postinduction in children older than one year (p < 0.05). Arrhythmias occurred in 3.3% of all patients. No patient experienced bradycardia. Other complications included hypotension (8.8% ) and mild laryngeal spasm (2.2% ). RESULTS: Halothane induction in children results in significant reduction in heart rate and blood pressure. Bradyarrhthmias are uncommon with promethazine premedication.

Prediction of difficult laryngoscopy in a population of Nigerian obstetric patients.

Difficulty in the maintenance of the airway during obstetric anaesthesia is a major contributory factor in anaesthetic related morbidity and mortality. There is an eightfold increase in the incidence of failed intubation in obstetrics. This is attributable to the physiological changes in pregnancy. Eighty consecutive obstetric patients, over a one year period who required general anaesthesia for caesarian section were evaluated using five bedside tests viz: Mallampati test, Thyrometal distance, Sterno-mental distance, Horizontal length of the Mandible and Inter-incisor gap. Eight patients had difficult laryngoscopy (10%). Mallampati test had a sensitivity, specificity and positive predictive value of 87.1%, 99.6% and 70% respectively. The values obtained for the Thyro-mental distance were 62.5%, 93.1% and 50% respectively. The other tests were not able to predict intubation difficulty significantly. When all tests were combined, sensitivity, specificity and positive predictive were values 100%, 36.1% and 14.8%. The combination of Mallampati and Thyro-mental distance had values of 100%, 93.1% and 61.5%--sensitivity, specificity and positive predictive value. Mallampati can be used as the sole predictor of difficult intubation in Nigerian obstetric patients.