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TESTING AMOXYCILLIN AND AMPICILLIN AS SEPARATE ANTIBIOTICS
1284 HYPOKALAEMIA
(<36’
(3 - 5 mmol/1) IN RELATION TO HYPOTHERMIA
5 OC) IN 226 PATIENTS DIRECTLY AFTER GASTROINTESTINAL OR VASCULAR SURGERY
had a mild serous discharge or redness, and 8 patients had severely infected wounds with a purulent discharge. Procedures and sepsis are outlined in the table. Since the time of Lister surgeons have striven to decrease the infection rates, and as part of this policy the concept of separate septic and clean theatres for accident-and-emergency departments was conceived. Using a single theatre we have achieved a severe infection rate of only 1 -6%, which is approaching an acceptable incidence. In future planning of accident-and-emergency departments which contemplate our types of minor surgery there is little need for separate clean and septic theatres. The ensuing financial saving should be considerable.
(6-1%) (1-6%)
,
patients the plasma potassium remained normal (see table). In the group with hypothermia and hypokalaemia partly compensated metabolic acidosis (pH 7-31±0-03, PC02 4-3 ±0-72 kPa [ 1 kPa =7-55 mm Hg]) was present in 15 (30%) and hyperglycaemia in 18 (36%) of the patients. Hypokalaemia could not be attributed to preoperative urinary potassium losses since these were smaller in hypokalaemic than in normokalaemic patients (mean 26-44 and 72 -5mmol, respectively). Complications (cardiac arrhythmia and failure, respiratory muscle insufficiency) due to hypokalaemia developed in 12 (24%) of the cases, and responded to intravenous potassium. We recommend correction of postoperative and accidental hypokalaemia by the intravenous route. In the presence of hyperglycaemia and/or metabolic acidosis hypokalaemia may not be anticipated but must be suspected in cases of hypothermia. If it is not, harmful treatment (bicarbonate and insulin infusions) may worsen the hypokalaemia, and infusion of calcium and digitalis therapy may be especially dangerous. Intensive Care Unit, Department of General
Surgery, University Hospital Dijkzigt, 3015 GD Rotterdam, Netherlands
H. A. BRUINING R. U. BOELHOUWER
DO ACCIDENT DEPARTMENTS NEED TWO THEATRES?
SIR,-There have been many studies on wound infections after inpatient surgical proceduresl2 but sepsis after minor surgery has been rarely investigated. There has been debate about whether the mixed operation load of septic and of minor, clean cases requires two separate operating-theatres. We have used one operating-theatre for all cases for the past ten years and we have assessed our sepsis rate prospectively to see if this arrangement is acceptable. During a three-year period all outpatient minor surgery was done in one theatre, clean cases preceding the potentially infected patients. Wounds were inspected at time of suture removal, and if pus or wound dehiscence was present the wound was classed as severely infected. If there was redness and/or a serous discharge the wound was considered to be mildly infected. No prophylactic antibiotics were used. 506 patients entered the study (279 male and 227 female) and the sepsis rate in clean cases was assessed. Of the 506 patients, 482 returned to the department for suture removal. Letters were sent to the remaining patients and further information was obtained in 9 (8 healed, 1 infected). Of the 491 patients for whom information was obtained, 450 (91’ 6%) achieved primary healing of their wounds without infection. 30 patients,
Accident and Emergency Royal Victoria Hospital, Belfast BT12 6BA
Department,
R. A. J. SPENCE W. H. RUTHERFORD
TESTING AMOXYCILLIN AND AMPICILLIN AS SEPARATE ANTIBIOTICS SIR,-The observation that a strain of Enterobacter cloacae was sensitive to ampicillin but resistant to amoxycillin/clavulanate (’Augmentin’)1 was explained by Professor Brumfitt and colleagues (Oct. 2, p. 768) as due to the fact that ampicillin is more active against Ent. cloacae than is amoxycillin. I have also demonstrated this effect with a strain of Providencia stuartii. However, two other strains of Prov. stuartii (figure) were sensitive to both ampicillin and amoxycillin but resistant to augmentin. Further understanding of the action of amoxycillin/clavulanate is required to explain this. Perhaps the two components exhibit antagonism-or might clavulanate induce the production of a beta-lactamase? It would appear that discrepancies between amoxycillin and ampicillin are not uncommon. For instance, amoxycillin is about two times more active than ampicillin against Streptococcusfaecalis and Salmonella sppbut has half the activity of ampicillin against Shigella spp.3 Haemophilus influenzae also appears less sensitive to amoxycillin than to ampicillin;4the same is true for anaerobic
bacteria.55
Amoxycillin
and
ampicillin should
be tested and
reported on as
different antibiotics. Department of Microbiology, Royal West Sussex Hospitals (St Richard’s), Chichester, West Sussex PO19 4SE 1.
Crump J, Cansdale S.
Enterobacter
resistant to
A. J. LETCHFORD amoxycillin/clavulanate. Lancet 1982;
ii 500. 2. Sabto 3. 4. 5.
J, Carson P, Morgan T. Evaluation of amoxycillin; a new semisynthetic penicillin. Med J Aust 1973; ii: 537. New HC. Antimicrobial activity and human pharmacology of amoxicillin. J Infect Dis 1974; 129 (suppl.) 123 Kasmidis J, Williams JD, Andrews J, Goodall JAD, Geddes AM. Amoxycillinpharmacology, bacteriology and clinical studies. Br J Clin Pract 1972; 26: 341. Sutter VL, Finegold SM. Susceptibility of anaerobic bacteria to 23 antimicrobial agents Antimicrob Ag Chemother 1976; 10: 736.
1. Cruse
PJE. A five-year prospective study of 23,649 surgical wounds. Arch Surg 1973; 107: 206-10. 2. Ljungqvist U, Lund MD. Wound sepsis after clean operations Lancet 1964; ii 1095-97. OUTCOME OF
491
CLEAN SURGICAL CASES
Providencia stuartii (ED5) centre of plate sensitive to ampicillin (AP25) and amoxycillin (A) but resistant to augmentin (Aug). Control is Escherichia coli NCTC 10418.
(<36’
(3 - 5 mmol/1) IN RELATION TO HYPOTHERMIA
5 OC) IN 226 PATIENTS DIRECTLY AFTER GASTROINTESTINAL OR VASCULAR SURGERY
had a mild serous discharge or redness, and 8 patients had severely infected wounds with a purulent discharge. Procedures and sepsis are outlined in the table. Since the time of Lister surgeons have striven to decrease the infection rates, and as part of this policy the concept of separate septic and clean theatres for accident-and-emergency departments was conceived. Using a single theatre we have achieved a severe infection rate of only 1 -6%, which is approaching an acceptable incidence. In future planning of accident-and-emergency departments which contemplate our types of minor surgery there is little need for separate clean and septic theatres. The ensuing financial saving should be considerable.
(6-1%) (1-6%)
,
patients the plasma potassium remained normal (see table). In the group with hypothermia and hypokalaemia partly compensated metabolic acidosis (pH 7-31±0-03, PC02 4-3 ±0-72 kPa [ 1 kPa =7-55 mm Hg]) was present in 15 (30%) and hyperglycaemia in 18 (36%) of the patients. Hypokalaemia could not be attributed to preoperative urinary potassium losses since these were smaller in hypokalaemic than in normokalaemic patients (mean 26-44 and 72 -5mmol, respectively). Complications (cardiac arrhythmia and failure, respiratory muscle insufficiency) due to hypokalaemia developed in 12 (24%) of the cases, and responded to intravenous potassium. We recommend correction of postoperative and accidental hypokalaemia by the intravenous route. In the presence of hyperglycaemia and/or metabolic acidosis hypokalaemia may not be anticipated but must be suspected in cases of hypothermia. If it is not, harmful treatment (bicarbonate and insulin infusions) may worsen the hypokalaemia, and infusion of calcium and digitalis therapy may be especially dangerous. Intensive Care Unit, Department of General
Surgery, University Hospital Dijkzigt, 3015 GD Rotterdam, Netherlands
H. A. BRUINING R. U. BOELHOUWER
DO ACCIDENT DEPARTMENTS NEED TWO THEATRES?
SIR,-There have been many studies on wound infections after inpatient surgical proceduresl2 but sepsis after minor surgery has been rarely investigated. There has been debate about whether the mixed operation load of septic and of minor, clean cases requires two separate operating-theatres. We have used one operating-theatre for all cases for the past ten years and we have assessed our sepsis rate prospectively to see if this arrangement is acceptable. During a three-year period all outpatient minor surgery was done in one theatre, clean cases preceding the potentially infected patients. Wounds were inspected at time of suture removal, and if pus or wound dehiscence was present the wound was classed as severely infected. If there was redness and/or a serous discharge the wound was considered to be mildly infected. No prophylactic antibiotics were used. 506 patients entered the study (279 male and 227 female) and the sepsis rate in clean cases was assessed. Of the 506 patients, 482 returned to the department for suture removal. Letters were sent to the remaining patients and further information was obtained in 9 (8 healed, 1 infected). Of the 491 patients for whom information was obtained, 450 (91’ 6%) achieved primary healing of their wounds without infection. 30 patients,
Accident and Emergency Royal Victoria Hospital, Belfast BT12 6BA
Department,
R. A. J. SPENCE W. H. RUTHERFORD
TESTING AMOXYCILLIN AND AMPICILLIN AS SEPARATE ANTIBIOTICS SIR,-The observation that a strain of Enterobacter cloacae was sensitive to ampicillin but resistant to amoxycillin/clavulanate (’Augmentin’)1 was explained by Professor Brumfitt and colleagues (Oct. 2, p. 768) as due to the fact that ampicillin is more active against Ent. cloacae than is amoxycillin. I have also demonstrated this effect with a strain of Providencia stuartii. However, two other strains of Prov. stuartii (figure) were sensitive to both ampicillin and amoxycillin but resistant to augmentin. Further understanding of the action of amoxycillin/clavulanate is required to explain this. Perhaps the two components exhibit antagonism-or might clavulanate induce the production of a beta-lactamase? It would appear that discrepancies between amoxycillin and ampicillin are not uncommon. For instance, amoxycillin is about two times more active than ampicillin against Streptococcusfaecalis and Salmonella sppbut has half the activity of ampicillin against Shigella spp.3 Haemophilus influenzae also appears less sensitive to amoxycillin than to ampicillin;4the same is true for anaerobic
bacteria.55
Amoxycillin
and
ampicillin should
be tested and
reported on as
different antibiotics. Department of Microbiology, Royal West Sussex Hospitals (St Richard’s), Chichester, West Sussex PO19 4SE 1.
Crump J, Cansdale S.
Enterobacter
resistant to
A. J. LETCHFORD amoxycillin/clavulanate. Lancet 1982;
ii 500. 2. Sabto 3. 4. 5.
J, Carson P, Morgan T. Evaluation of amoxycillin; a new semisynthetic penicillin. Med J Aust 1973; ii: 537. New HC. Antimicrobial activity and human pharmacology of amoxicillin. J Infect Dis 1974; 129 (suppl.) 123 Kasmidis J, Williams JD, Andrews J, Goodall JAD, Geddes AM. Amoxycillinpharmacology, bacteriology and clinical studies. Br J Clin Pract 1972; 26: 341. Sutter VL, Finegold SM. Susceptibility of anaerobic bacteria to 23 antimicrobial agents Antimicrob Ag Chemother 1976; 10: 736.
1. Cruse
PJE. A five-year prospective study of 23,649 surgical wounds. Arch Surg 1973; 107: 206-10. 2. Ljungqvist U, Lund MD. Wound sepsis after clean operations Lancet 1964; ii 1095-97. OUTCOME OF
491
CLEAN SURGICAL CASES
Providencia stuartii (ED5) centre of plate sensitive to ampicillin (AP25) and amoxycillin (A) but resistant to augmentin (Aug). Control is Escherichia coli NCTC 10418.