- Email: [email protected]
Antibiotics for marine vibrios
568
Operator and assistant positions during cardiac catheterisation via femoral (left) and brachial (right) The radiation dose to the operator averaged 20-6 pSv per case of cardiac catheterisation via the femoral approach, and 55-7(iSv when the brachial approach was used (p < 0-0001). The 99% confidence interval for the difference of 35-1 J..lSV was 25-9-44-3 )iSv. Figures for the assistant nurse were, respectively, 6-3 )iSv and 12-8 )iSv, and the 99% confidence interval for the difference of 6-5 (iSv was 3-4-9-6 pSv. The radiation doses given here are high because we included many cases with very long screening times. In our hospital cardiac catheterisations via the femoral approach outnumber those via the brachial approach by about9 to 1, and the arm route is used for investigation of more complex valvular disease. This ratio is not reflected in the selected series discussed here (table). How much of the greater radiation dose during catheterisation via the brachial approach is due to the greater proximity of the operators to the radiation source and how much is due to the lack of a protective shield is uncertain. A new catheterisation laboratory was installed in our hospital after the above study period, and this has a screen that can be used for both methods of cardiac catheterisation. Preliminary data suggest no significant difference between the radiation doses (30Sv with the femoral approach [n = 20], 45Sv with the brachial [n = 22]; 99% confidence interval for 15 )iSv difference - 16-4 to 46-4p.Sv). We recommend the use of radiation protection shields suited to catheterisation via the brachial approach. We thank Mrs Anne Allington, Mrs Ann Dixon-Brown, and Sister Belinda Boulton for their assistance.
Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
1.
A. PIPILIS O. ORMEROD L. B. TAN
Jeans SP, Faulkner K, Love HG, Bardsley RA. An investigation of the radiation dose to staff during cardiac radiological studies. Br J Radiol 1985; 58: 419-28.
routes.
’Vingmed CFM 700’ imaging system. Microbubbles were generated in 8-10 ml normal saline or 5% dextrose by the two-syringe and three-way tap methodand were injected rapidly via a 19-gauge butterfly needle in the dorsum of the hand. Initially, up to three injections were given with the subject breathing quietly and normally. If no shunt was demonstrated, up to another three injections were given with the subject performing a Valsalva manoeuvre. If any bubbles were seen in the left heart, no further injections were given. A result was judged positive if any bubbles were seen in the left heart. We made no attempt to quantify the size of the shunt. All the studies were recorded on videotape and subsequently re-analysed: no new shunts were identified. In this series of 19 patients, 6 proved to have a right-to-left shunt. 3 of these 6 had had neurological DCS. The incidence of right-to-left shunt was 31-6% (95% confidence intervals, 126-565%). The 32% frequency that Wilmshurst found in his control group of 63 divers who had not had DCS is within this range, as is the 18% reported in a healthy population of 76 non-divers also investigated by this method.4 Our findings are at variance with the 66 % frequency of shunt found by Wilmshurst in 29 divers with neurological DCS (chi-squared test, p < 005). Our findings do not support the hypothesis that a shunt demonstrated in this way predisposes divers to neurological DCS. We suggest that recommendations on the management of divers with such a shunt should be delayed until there is conclusive evidence. A further large controlled study is indicated, which we propose to do. Department of Cardiology, Aberdeen Royal Infirmary, Aberdeen AB9 2ZD, UK; and Hyperbaric Medicine Unit, Aberdeen Royal Infirmary
STEPHEN J. CROSS LESLEY F. THOMSON KEVIN P. JENNINGS THOMAS G. SHIELDS
1. Moon
SiR,—Moon and Wilmshurst2 and their colleagues have demonstrated, with contrast echocardiography, a high frequency
RE, Camporesi EM, Kisslo JA. Patent foramen ovale and decompression sickness in divers. Lancet 1989; i: 513-14 2. Wilmshurst PT, Byme JC, Webb-Peploe JC. Relation between interatrial shunts and decompression sickness in divers. Lancet 1989; ii: 1302-05. 3. Lechat PH, Mas JL, Lascault G, et al Prevalence of patent foramen ovale in patients with stroke. N Engl JMed 1988; 318: 1148-52. 4. Lynch JJ, Schuchard GH, Gross CM, Warm LS. Prevalence of right to left atrial shunting in a healthy population: detection by Valsalva manoeuvre contrast echocardiography. Am J Cardiol 1984; 53: 1478-80.
of right-to-left shunt in divers who have had neurological decompression sickness (DCS). This shunt has been presumed to be due to a patent foramen ovale. There are no firm guidelines (only
Antibiotics for marine vibrios
Right-to-left shunt and neurological decompression sickness in divers
much discussion and controversy) on the further management of divers who prove to have a shunt. Because of these studies1.2we now routinely screen all divers who present to our hyperbaric unit with neurological DCS for evidence of a right-to-left shunt. We here report our results. Since October, 1989, we have examined 17 male and 2 female divers (mean age 31-4 years, range 22-52) who presented to our hyperbaric unit with neurological DCS; 7 were recreational and 12 were professional divers. 9 of these 19 divers had had previous neurological DCS. Echocardiographic studies were done with a
SIR,-Your editorial (July 28, p 215) notes that most Vibrio species sensitive to chloramphenicol, gentamicin, and tetracycline, and suggests that the quinolones should be evaluated. We tested 244 marine vibrios (18 V vulnificus) from nine different species against 23 antibiotics, including the quinolones ofloxacin, norfloxacin, enoxacin, pefloxacin, and ciprofloxacin.’ Ciprofloxacin was the most active, and only 1 isolate (a 1 parahaemolyticus) was resistant to 1 mg/1. Almost all strains were also sensitive to chloramphenicol, tetracycline, gentamicin, amikacin, cefotaxime, ceftazidime, are
569
aztreonam, and imipenem. However, a few isolates of some species,
RESULTS OF NEONATAL INTENSIVE CARE UNIT QUESTIONNAIRE
especially Vparahaemolyticus and Valginolyticus, showed unusual and multiple resistance to some of these drugs, including resistance to chloramphenicol and tetracycline. 1 of the Vvulnificus strains was resistant to cefotaxime and 4 to aztreonam. Halophilic vibrios grew poorly or not at all on sensitivity-testing media incubated at 37°C without the addition of salt, but inocula of 10 colony-forming units grow well on unsupplemented MuellerHinton agar incubated at 30°C. Since these are unusual test conditions it is important to include Vibrio controls. We have published results for USA and UK standard strains to aid inter-laboratory comparisons.1 V vulnificus is the most common cause of fatal spreading necrotising lesions among the vibrios,2,3 but they have also been seen with V parahaemolyticus, V alginolyticus, and V damsela.3-f> Your editorial notes that adequate surgical debridement is important for soft tissue infections and we would strongly endorse this. No antibiotic will penetrate dead tissue and in these life-threatening conditions emergency debridement or amputation is essential. Blind therapy with reliable systemic drugs is also required, and, on the basis of our results and anecdotal clinical experience, the aminoglycosides, ceftazidime, imipenem, or the quinolones should be effective. Department of Microbiology, United Medical and Dental Schools,
Guy’s Hospital, London SE1 7RT, UK
G. L. FRENCH
1. French GL, Woo ML, Hui YW, Chan KY. Antimicrobial susceptibilities of halophilic vibrios. J Antimicrob Chemother 1989; 24: 183-94. 2. Woo ML, Patrick WGD, Simon MTP, French GL. Necrotising fasciitis caused by Vibrio vulnificus. J Clin Pathol 1984; 37: 1301-04. 3. Howard RJ, Pessa ME, Brennaman BH, Ramphal R. Necrotizing soft-tissue infections caused by marine vibrios. Surgery 1985; 98: 126-30. 4. Johnson DE, Weinberg L, Ciarkowski J, West P, Colewell RR. Wound infection caused by Kanagawa-negative Vibrio parahaemolyticus. J Clin Microbiol 1984; 20: 811-12. 5. Bonner JR, Coker AS, Berryman CR, Pollack HM. Spectrum of vibno infections in a Gulf Coast community. Ann Intern Med 1983; 99: 464-69. 6. Coffey JA, Hams RL, Rutledge MJ, Bradshaw MW, Williams TW. Vibrio damsela: another potentially virulent marine vibrio J Infect Dis 1986; 153: 800-01.
Pain relief in neonatal intensive care SIR,-We believe that the need for pain relief in sick babies has been insufficiently recognised.l,2 This is despite the fact that it is generally accepted that babies feel pain as much as older children or adults.3,4 To assess pain relief practice in neonatal intensive care units we sent questionnaires to 21 units in the UK and Ireland. The questionnaire was addressed to the "Sister in charge of the unit", asked to discuss it with all staff. Results from the 17 questionnaires returned are shown in the table. It appears that while all units in this survey accept that babies experience pain, alleviation of pain is given a low priority. Policies for pain relief are poorly defined, only 2 units having a written policy. In 75% or more of cases no analgesia was given for necrotising enterocolitis and meningitis. There was a strong feeling that analgesia is underprescribed by doctors and a significant minority felt that, even when prescribed, analgesics are underadministered by nurses. We feel that doctors and nurses should translate their awareness of pain in the newborn into concrete procedures for alleviation. The nurse delegated to care for the baby has an important role in looking for behavioural manifestations of distress. These are important observations and should not be dismissed by other staff making casual observations. There should be a written policy on every neonatal unit with regard to pain relief otherwise it will frequently not be administered. Doctors should not underprescribe and nurses should not be afraid to administer. While the provision of adequate analgesia may cause problems (eg, apnoea and abolition of helpful clinical signs), this should not preclude its use when warranted. After receiving a narcotic, babies should be observed closely, and a narcotic antagonist and oxygen should be near at hand. Traumatic procedures should not be undertaken without the use of analgesia, except in dire emergencies; for example, the chest wall should be infiltrated with lignocaine before insertion of a drain. Greater use can be made of local anaesthetic sprays and creams. Equally who
was
important is the comfort that can be given by non-pharmacological measures,though these cannot deal adequately with intense pain from traumatic procedures. The results from the fmal question in our survey point towards poor pain assessment. It is likely that improved training can overcome this problem. Finally, we should recall that the Latin infans, from which the word infant derives, means speechless, and strive to ensure that babies in our care do not suffer. This study was undertaken as a research project during the neonatal intensive care course at the National Maternity Hospital, Dublin. We would like to thank the staff of the neonatal units in the Republic of Ireland and UK who made this study possible.
JANE TOHILL
National Maternity Hospital, Hollis Street, Dublin, Ireland
OLIVE MCMORROW
1. Owens ME. Pain in infancy. Conceptual and methodological issues. Pain 1984; 20: 213-30. 2. Owens ME, Todd EM. Pain in infancy. Neo-natal reaction to heel lance. Pain 1984;
20: 77-86. 3. Hatch DJ. Analgesia in the neonate. Br Med J 1987; 294: 920. 4. Bray RJ. Management of preoperative pain. Child Hosp Up-date 1988; May: 1565-72. 5. Allingham L. Pain in the neonate. Midwives Chronicle 1989; Feb: 54-56.
Growth and nutrition in children with cerebral palsy SiR,—Your May 26 editorial prompted us to look more closely at data on a total population (n 897) of low-birthweight infants (less than 1750 g) born in Scotland in 1984.’ Of the surviving cohort, =
our
611 (96%) have been reviewed at the age of 4i years, with Amiel Tison and Stewart’s2 standardised neuromotor assessment, and including measures of growth and cognitive function which will be reported in full shortly. The distributions of height, head circumference, and, in particular, weight centiles showed pronounced shifts to the left; the distribution of weight centiles was related to birthweight (figure). Patients were classified in three groups according to neuromotor impairment: those with neuromotor signs only; those with a moderate disability; and those with severe disability. Among the children whose motor deficit was accompanied by severe disability there was a U-shaped distribution in head circumference; the distribution of height showed a striking shift to the left, and more than 30% were below the 3rd centile. There was a slight shift to the left in weight, with no children at or above the 90th centile at 4z years
(figure).
Operator and assistant positions during cardiac catheterisation via femoral (left) and brachial (right) The radiation dose to the operator averaged 20-6 pSv per case of cardiac catheterisation via the femoral approach, and 55-7(iSv when the brachial approach was used (p < 0-0001). The 99% confidence interval for the difference of 35-1 J..lSV was 25-9-44-3 )iSv. Figures for the assistant nurse were, respectively, 6-3 )iSv and 12-8 )iSv, and the 99% confidence interval for the difference of 6-5 (iSv was 3-4-9-6 pSv. The radiation doses given here are high because we included many cases with very long screening times. In our hospital cardiac catheterisations via the femoral approach outnumber those via the brachial approach by about9 to 1, and the arm route is used for investigation of more complex valvular disease. This ratio is not reflected in the selected series discussed here (table). How much of the greater radiation dose during catheterisation via the brachial approach is due to the greater proximity of the operators to the radiation source and how much is due to the lack of a protective shield is uncertain. A new catheterisation laboratory was installed in our hospital after the above study period, and this has a screen that can be used for both methods of cardiac catheterisation. Preliminary data suggest no significant difference between the radiation doses (30Sv with the femoral approach [n = 20], 45Sv with the brachial [n = 22]; 99% confidence interval for 15 )iSv difference - 16-4 to 46-4p.Sv). We recommend the use of radiation protection shields suited to catheterisation via the brachial approach. We thank Mrs Anne Allington, Mrs Ann Dixon-Brown, and Sister Belinda Boulton for their assistance.
Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
1.
A. PIPILIS O. ORMEROD L. B. TAN
Jeans SP, Faulkner K, Love HG, Bardsley RA. An investigation of the radiation dose to staff during cardiac radiological studies. Br J Radiol 1985; 58: 419-28.
routes.
’Vingmed CFM 700’ imaging system. Microbubbles were generated in 8-10 ml normal saline or 5% dextrose by the two-syringe and three-way tap methodand were injected rapidly via a 19-gauge butterfly needle in the dorsum of the hand. Initially, up to three injections were given with the subject breathing quietly and normally. If no shunt was demonstrated, up to another three injections were given with the subject performing a Valsalva manoeuvre. If any bubbles were seen in the left heart, no further injections were given. A result was judged positive if any bubbles were seen in the left heart. We made no attempt to quantify the size of the shunt. All the studies were recorded on videotape and subsequently re-analysed: no new shunts were identified. In this series of 19 patients, 6 proved to have a right-to-left shunt. 3 of these 6 had had neurological DCS. The incidence of right-to-left shunt was 31-6% (95% confidence intervals, 126-565%). The 32% frequency that Wilmshurst found in his control group of 63 divers who had not had DCS is within this range, as is the 18% reported in a healthy population of 76 non-divers also investigated by this method.4 Our findings are at variance with the 66 % frequency of shunt found by Wilmshurst in 29 divers with neurological DCS (chi-squared test, p < 005). Our findings do not support the hypothesis that a shunt demonstrated in this way predisposes divers to neurological DCS. We suggest that recommendations on the management of divers with such a shunt should be delayed until there is conclusive evidence. A further large controlled study is indicated, which we propose to do. Department of Cardiology, Aberdeen Royal Infirmary, Aberdeen AB9 2ZD, UK; and Hyperbaric Medicine Unit, Aberdeen Royal Infirmary
STEPHEN J. CROSS LESLEY F. THOMSON KEVIN P. JENNINGS THOMAS G. SHIELDS
1. Moon
SiR,—Moon and Wilmshurst2 and their colleagues have demonstrated, with contrast echocardiography, a high frequency
RE, Camporesi EM, Kisslo JA. Patent foramen ovale and decompression sickness in divers. Lancet 1989; i: 513-14 2. Wilmshurst PT, Byme JC, Webb-Peploe JC. Relation between interatrial shunts and decompression sickness in divers. Lancet 1989; ii: 1302-05. 3. Lechat PH, Mas JL, Lascault G, et al Prevalence of patent foramen ovale in patients with stroke. N Engl JMed 1988; 318: 1148-52. 4. Lynch JJ, Schuchard GH, Gross CM, Warm LS. Prevalence of right to left atrial shunting in a healthy population: detection by Valsalva manoeuvre contrast echocardiography. Am J Cardiol 1984; 53: 1478-80.
of right-to-left shunt in divers who have had neurological decompression sickness (DCS). This shunt has been presumed to be due to a patent foramen ovale. There are no firm guidelines (only
Antibiotics for marine vibrios
Right-to-left shunt and neurological decompression sickness in divers
much discussion and controversy) on the further management of divers who prove to have a shunt. Because of these studies1.2we now routinely screen all divers who present to our hyperbaric unit with neurological DCS for evidence of a right-to-left shunt. We here report our results. Since October, 1989, we have examined 17 male and 2 female divers (mean age 31-4 years, range 22-52) who presented to our hyperbaric unit with neurological DCS; 7 were recreational and 12 were professional divers. 9 of these 19 divers had had previous neurological DCS. Echocardiographic studies were done with a
SIR,-Your editorial (July 28, p 215) notes that most Vibrio species sensitive to chloramphenicol, gentamicin, and tetracycline, and suggests that the quinolones should be evaluated. We tested 244 marine vibrios (18 V vulnificus) from nine different species against 23 antibiotics, including the quinolones ofloxacin, norfloxacin, enoxacin, pefloxacin, and ciprofloxacin.’ Ciprofloxacin was the most active, and only 1 isolate (a 1 parahaemolyticus) was resistant to 1 mg/1. Almost all strains were also sensitive to chloramphenicol, tetracycline, gentamicin, amikacin, cefotaxime, ceftazidime, are
569
aztreonam, and imipenem. However, a few isolates of some species,
RESULTS OF NEONATAL INTENSIVE CARE UNIT QUESTIONNAIRE
especially Vparahaemolyticus and Valginolyticus, showed unusual and multiple resistance to some of these drugs, including resistance to chloramphenicol and tetracycline. 1 of the Vvulnificus strains was resistant to cefotaxime and 4 to aztreonam. Halophilic vibrios grew poorly or not at all on sensitivity-testing media incubated at 37°C without the addition of salt, but inocula of 10 colony-forming units grow well on unsupplemented MuellerHinton agar incubated at 30°C. Since these are unusual test conditions it is important to include Vibrio controls. We have published results for USA and UK standard strains to aid inter-laboratory comparisons.1 V vulnificus is the most common cause of fatal spreading necrotising lesions among the vibrios,2,3 but they have also been seen with V parahaemolyticus, V alginolyticus, and V damsela.3-f> Your editorial notes that adequate surgical debridement is important for soft tissue infections and we would strongly endorse this. No antibiotic will penetrate dead tissue and in these life-threatening conditions emergency debridement or amputation is essential. Blind therapy with reliable systemic drugs is also required, and, on the basis of our results and anecdotal clinical experience, the aminoglycosides, ceftazidime, imipenem, or the quinolones should be effective. Department of Microbiology, United Medical and Dental Schools,
Guy’s Hospital, London SE1 7RT, UK
G. L. FRENCH
1. French GL, Woo ML, Hui YW, Chan KY. Antimicrobial susceptibilities of halophilic vibrios. J Antimicrob Chemother 1989; 24: 183-94. 2. Woo ML, Patrick WGD, Simon MTP, French GL. Necrotising fasciitis caused by Vibrio vulnificus. J Clin Pathol 1984; 37: 1301-04. 3. Howard RJ, Pessa ME, Brennaman BH, Ramphal R. Necrotizing soft-tissue infections caused by marine vibrios. Surgery 1985; 98: 126-30. 4. Johnson DE, Weinberg L, Ciarkowski J, West P, Colewell RR. Wound infection caused by Kanagawa-negative Vibrio parahaemolyticus. J Clin Microbiol 1984; 20: 811-12. 5. Bonner JR, Coker AS, Berryman CR, Pollack HM. Spectrum of vibno infections in a Gulf Coast community. Ann Intern Med 1983; 99: 464-69. 6. Coffey JA, Hams RL, Rutledge MJ, Bradshaw MW, Williams TW. Vibrio damsela: another potentially virulent marine vibrio J Infect Dis 1986; 153: 800-01.
Pain relief in neonatal intensive care SIR,-We believe that the need for pain relief in sick babies has been insufficiently recognised.l,2 This is despite the fact that it is generally accepted that babies feel pain as much as older children or adults.3,4 To assess pain relief practice in neonatal intensive care units we sent questionnaires to 21 units in the UK and Ireland. The questionnaire was addressed to the "Sister in charge of the unit", asked to discuss it with all staff. Results from the 17 questionnaires returned are shown in the table. It appears that while all units in this survey accept that babies experience pain, alleviation of pain is given a low priority. Policies for pain relief are poorly defined, only 2 units having a written policy. In 75% or more of cases no analgesia was given for necrotising enterocolitis and meningitis. There was a strong feeling that analgesia is underprescribed by doctors and a significant minority felt that, even when prescribed, analgesics are underadministered by nurses. We feel that doctors and nurses should translate their awareness of pain in the newborn into concrete procedures for alleviation. The nurse delegated to care for the baby has an important role in looking for behavioural manifestations of distress. These are important observations and should not be dismissed by other staff making casual observations. There should be a written policy on every neonatal unit with regard to pain relief otherwise it will frequently not be administered. Doctors should not underprescribe and nurses should not be afraid to administer. While the provision of adequate analgesia may cause problems (eg, apnoea and abolition of helpful clinical signs), this should not preclude its use when warranted. After receiving a narcotic, babies should be observed closely, and a narcotic antagonist and oxygen should be near at hand. Traumatic procedures should not be undertaken without the use of analgesia, except in dire emergencies; for example, the chest wall should be infiltrated with lignocaine before insertion of a drain. Greater use can be made of local anaesthetic sprays and creams. Equally who
was
important is the comfort that can be given by non-pharmacological measures,though these cannot deal adequately with intense pain from traumatic procedures. The results from the fmal question in our survey point towards poor pain assessment. It is likely that improved training can overcome this problem. Finally, we should recall that the Latin infans, from which the word infant derives, means speechless, and strive to ensure that babies in our care do not suffer. This study was undertaken as a research project during the neonatal intensive care course at the National Maternity Hospital, Dublin. We would like to thank the staff of the neonatal units in the Republic of Ireland and UK who made this study possible.
JANE TOHILL
National Maternity Hospital, Hollis Street, Dublin, Ireland
OLIVE MCMORROW
1. Owens ME. Pain in infancy. Conceptual and methodological issues. Pain 1984; 20: 213-30. 2. Owens ME, Todd EM. Pain in infancy. Neo-natal reaction to heel lance. Pain 1984;
20: 77-86. 3. Hatch DJ. Analgesia in the neonate. Br Med J 1987; 294: 920. 4. Bray RJ. Management of preoperative pain. Child Hosp Up-date 1988; May: 1565-72. 5. Allingham L. Pain in the neonate. Midwives Chronicle 1989; Feb: 54-56.
Growth and nutrition in children with cerebral palsy SiR,—Your May 26 editorial prompted us to look more closely at data on a total population (n 897) of low-birthweight infants (less than 1750 g) born in Scotland in 1984.’ Of the surviving cohort, =
our
611 (96%) have been reviewed at the age of 4i years, with Amiel Tison and Stewart’s2 standardised neuromotor assessment, and including measures of growth and cognitive function which will be reported in full shortly. The distributions of height, head circumference, and, in particular, weight centiles showed pronounced shifts to the left; the distribution of weight centiles was related to birthweight (figure). Patients were classified in three groups according to neuromotor impairment: those with neuromotor signs only; those with a moderate disability; and those with severe disability. Among the children whose motor deficit was accompanied by severe disability there was a U-shaped distribution in head circumference; the distribution of height showed a striking shift to the left, and more than 30% were below the 3rd centile. There was a slight shift to the left in weight, with no children at or above the 90th centile at 4z years
(figure).