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Pandemic influenza and pediatric intensive care*

Nap, Raoul E. PhD; Andriessen, Maarten P. H. M. PhD; Meessen, Nico E. L. PhD; Albers, Marcel J. I. J. PhD; van der Werf, Tjip S. PhD

Pediatric Critical Care Medicine: March 2010 - Volume 11 - Issue 2 - p 185-198
doi: 10.1097/PCC.0b013e3181cbdd76
Special Articles
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Objective: To assess the adequacy of preparedness planning for an influenza pandemic by modeling the pediatric surge capacity of healthcare facility and pediatric intensive care unit (PICU) requirements over time. Governments and Public Health authorities have planned preparedness activities and training for a flu pandemic. PICU facilities will be the limiting factor in healthcare provision for children but detailed analyses for needs and demands in PICU care have not been published.

Design: Based on the Center for Disease Control and Prevention and World Health Organization estimates and published models of the expected evolution of pandemic flu, we modeled the pediatric surge capacity of healthcare facility and PICU requirements over time. Various scenarios with different assumptions were explored. We compared these demands with estimates of maximal PICU capacity factoring in healthcare worker absenteeism as well as reported and more realistic estimates derived from semistructured telephone interviews with key stakeholders in ICUs in the study area.

Setting: All hospitals and intensive care facilities in the Northern Region in The Netherlands with near 1.7 million inhabitants, of whom approximately 25% is <18 yrs.

Measurements and Main Results: Using well-established modeling techniques, evidence-based medicine, and incorporating estimates from the Centers for Disease Control and Prevention and World Health Organization, we show that PICU capacity may suffice during an influenza pandemic. Even during the peak of the pandemic, most children requiring PICU admission may be served, even those who have nonflu-related conditions, provided that robust indications and decision rules are maintained, both for admission, as well as continuation (or discontinuation) of life support.

Conclusions: We recommend that a model, with assumptions that can be adapted with new information obtained during early stages of the pandemic that is evolving, be an integral part of a preparedness plan for a pandemic influenza with new human transmissible agent like influenza A virus.

From the Directorate of Medical Affairs, Quality and Safety (REN, MPHMA); Department of Medical Microbiology (NELM), Division of Infection Control; Department of Pediatrics (MJIJA), Division of Intensive Care, Beatrix Children's Hospital, Groningen, Netherlands; Departments of Internal Medicine (TSvdW), and Pulmonary Diseases and Tuberculosis, Infectious Diseases Service and Tuberculosis Unit, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands.

*See also p. 299.

The authors have not disclosed any potential conflicts of interest.

For information regarding this article, E-mail: r.e.nap@rvb.umcg.nl

The current H1N1 influenza has forced healthcare authorities and health services in The Netherlands to update their preparedness plans for an influenza pandemic (1–7). The evolving H1N1 is reflected by 378,223 laboratory confirmed cases as of October 4, 2009, with at least 4525 human deaths, of which >50% are children (<19 yrs of age) (8, 9). The increasing pandemic threat of influenza A (H5N1) is reflected by 442 cases of human disease reported to the World Health Organization as of September 24, 2009, with 262 human deaths, of which 50% are children (<19 yrs of age) (10).

Preparing for an influenza pandemic is difficult for healthcare systems because of many uncertainties. Strikingly little knowledge has been obtained from the scattered cases of avian influenza in humans (11), including the impact of an influenza pandemic on children (12, 13). The percentage of patients falling ill after acquiring the virus (attack rate), the percentage requiring hospital admission and, subsequently, intensive care unit (ICU) admission, the hospital and ICU length of stay and death rate can only accurately be factored in after a new virus has emerged (3). Therefore, almost all assumptions in the models published to date have drawn on the knowledge obtained from the large 20th century pandemics (14–16). A model for preparedness of the healthcare system should be highly adaptable and flexible to factor in new information emerging in the early stages of the pandemic. In the present study, we focused our preparedness plan on children, assuming an outbreak pattern similar to that of the Spanish flu (17–20) and the Hong Kong flu (19).

We present a model, similar to models by Anderson et al (21) for Australia and New Zealand and Menon et al for England (16), specifically designed for pediatric influenza-like illness (ILI) cases. Specific attention to hospitalization of children is justified. First, they represent a disproportionately large cohort of expected ILI patients; second, the effect of using neuraminidase inhibitors to treat influenza in children is still uncertain; third, children have an increased risk of bacterial pneumonia after ILI with increased risk of dying (20, 22, 23); and finally, pediatric healthcare workers (HCWs) are underrepresented in national and local pandemic influenza preparedness planning (20). In our model, we show the effect on pediatric intensive care unit (PICU) bed occupancy of increased hospitalization of children into a single specialized center, in combination with HCWs absenteeism. Our model is based on key principles of disaster management. This includes the assumption that “older children” between the ages of 7 yrs and 18 yrs would need be admitted to adult ICUs if PICU capacity proves to be insufficient. A recent (confidential) report from the Taskforce Influenza Dutch Society for Intensive Care (NVIC) to the Minister of Health in The Netherlands and the European Resuscitation Council Guidelines suggest that children from age 8 without underlying physical conditions can be safely cared for in an adult intensive care environment (24, 25). For this strict and clear triage, protocols must be implemented. Furthermore, we discuss the choices to be made for ongoing noninfluenza-related emergencies during an influenza pandemic and the effect of enhancing the contingency plans already in place.

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MATERIALS AND METHODS

The University Medical Center Groningen (UMCG) is a large tertiary care university hospital covering approximately 12% of the total Dutch population and approximately 30% of the total surface area of The Netherlands. Under Dutch law, UMCG has an important role in the event of an influenza pandemic, not only for the patient population that it serves but also as a regional coordinating center. The UMCG is the only hospital in the region with pediatric and neonatal intensive care capacity. Therefore, all children requiring some form of mechanical ventilatory support, will need to be admitted to the UMCG, putting additional strain on already tight surge capacity. Adults requiring some form of mechanical ventilatory support can be distributed among the ICUs in the 15 hospitals in the northern region of The Netherlands.

We used FluSurge 2.0 (26) and a computer model in an Excel file developed by one of the authors (R.E.N.) to calculate the impact of an influenza pandemic in The Netherlands on hospital admission and occupancy rate of all ICU beds (i.e., those with facilities for mechanical ventilation) in the northern region of The Netherlands. Data on population (≈1.7 million) and age distribution (Table 1) were obtained from publicly available sources. The age distribution in the Dutch population data were provided in 5-yr groupings; we, therefore, converted these data to an even distribution to allow for calculations with the FluSurge program (16). Data on total (pediatric) hospital beds, neonatal, pediatric, and adult ICU beds, and number of pediatricians, pediatric nurses, medical specialists, and nurses and their full-time equivalents were obtained from publicly available sources (27). Pediatric and adult ICU capacity was obtained from reports from hospital administrators during training sessions for pandemic influenza, organized by the public health authorities in the region. These data on reported ICU capacity were discussed during a semistructured telephone interview with ICU medical staff. Using these data, we estimated the regular pediatric hospital and PICU bed capacity and maximum surge capacity. We calculated the impact of an influenza pandemic on hospital and intensive care resources, utilizing only adult intensive care beds, for calculations for the entire population, including children. In these calculations, we used all resources available in 14 general and one university hospital (i.e., UMCG) (5). These calculations included the use of ventilators from operating theaters under the premises that all planned care can be postponed leaving acute care and ILI patients. Under these premises, no shortage of mechanical ventilators might be expected. Data on the impact of a pandemic influenza on healthcare services were adopted from the National Institute for Public Health and the Environment (RIVM) (28, 29). RIVM presented tables for 25% and 50% disease attack rates, representing best and worst case scenarios. A 30% attack rate is the most likely scenario, according to the Centers for Disease Control and Prevention, and is defined as the most likely scenario by RIVM. As the PICU capacity is extremely limited, we made calculations for two different scenarios: one in which all pediatric patients would be admitted to PICU beds; and one in which only smaller children were admitted to PICU, whereas older children would be admitted to adult ICUs. Most adult ICUs would be able to technically manage children of ≥25 kg; smaller children require different equipment and disposables (24). Adult ICUs are therefore equipped to handle patients weighing ≥25 kg. In The Netherlands, boys aged 7 yrs and girls aged 8 yrs are expected to weigh about 25 kg and, hence, can be admitted to an adult ICU. From the RIVM tables, we calculated the 30% attack rate by linear transformation for the three groups: <18 yrs; <7 yrs (Table 2A and B); and >18 yrs (Table 2C). We also calculated the total number of children admitted to the regional hospitals at each point in time during the pandemic. We defined the first day (day 0) as the moment of first human-to-human transmission (phase IV or V in the current World Health Organization phase of pandemic alert). We took into account the time each child occupies a hospital or ICU bed (range, 8–15 days), on the basis of experience with patients admitted to the ICU with a diagnosis of pneumonia or sepsis. Finally, we incorporated estimated risk of death per patient, reducing the number of admitted children by death rate at any one time. Because the data of the RIVM are in week blocks, we evenly distributed the number of hospital admissions and the proportion of deaths across the week days.

Table 1

Table 1

Table 2

Table 2

In our calculations, we also factored the effect of treatment (within 48 hrs of infection) with antiviral medication on the spread and the impact of the pandemic, although the exact effect size is still uncertain, specifically for children (16, 30). Antiviral medication is assumed to reduce the total number of hospital admissions by 50% and death rate by ≈30% (29).

In addition, we incorporated in the model the probable absenteeism of HCWs either due to illness or to care duties at home or in individual social environments. We assumed that HCWs will fall ill at a rate similar to that of the general population. We extrapolated national population data of illness and deaths to the total number of HCWs in our HCW database.

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RESULTS

We present the impact of a pandemic on children with new human-to-human-transmissible influenza on hospital and PICU resources in the UMCG. Using the figures of the RIVM, and assuming a 30% cumulative disease attack rate, we estimated that approximately 12% of the population of children will consult a general practitioner (Table 2AC). The percentage of children triaged for hospital admission is 0.3%. We assumed excess deaths among these selected patients, some 25% or 50% of whom may require mechanical ventilation, for age groups below 18 yrs (Fig. 1), age group <7 yrs (Fig. 2), and age groups >18 yrs (Fig. 3). In the northern part of The Netherlands, 5629 regular hospital beds are available. The hospitals in this region have a total of 30% (noninfluenza-related) acute care, which would leave 3940 regular hospital beds that could be made available for influenza-related hospital admissions. In addition, the UMCG has 100 pediatric hospitals beds, of which 70 could be made available for influenza-related hospital admissions. If the attack rate reaches a maximum of 50% with a mean length of stay of 15 hospital days per child, without any additional change in patient management, this would lead to a peak of 282 occupied regular pediatric hospital beds in the age group <18 yrs, which would suffice for influenza-related acute care. Therefore, we centered our calculations around the peak occupancy of PICU beds. We calculated the number of hospital admissions per week, spread evenly across 7 days in the respective week, and we subtracted the number of deaths, also evenly spread across the week. We assumed that 25% to 50% of total hospital admission pediatric patients would require some form of mechanical ventilatory support, and we provide calculations for the extremes of our estimates. On the basis of results from a semistructured telephone interview with ICU medical staff in the UMCG, a maximum of 31 (total n = 46) PICU beds and a maximum of 136 adult ICU beds (total n = 200) could be used for influenza-related acute care patients. Furthermore, a total of approximately 70 (total n = 100) operating theater beds with mechanical ventilators can be available for a short period of time, allowing 30 operating theater beds for acute postoperative care. We estimate that 31 PICU beds and 136 adult ICU beds will be made available in a short period. In the scenario of no additional intervention, if the full capacity of all 31 PICU beds is used, with an attack rate of 30%, 25% ICU admission rate, and a mean length of stay of 8 days, we would have a shortage of one PICU bed at day 28 after onset, when we expect the pandemic to peak. This shortage of ICU capacity is exacerbated with any increase in hospital length of stay or ICU length of stay. As HCWs will become ill in the pandemic in proportion to the attack rate in the general population, we illustrated the impact of HCW absenteeism on loss of ICU bed capacity for all presented scenarios (Figs. 1–3).

Figure 1.

Figure 1.

Figure 1.

Figure 1.

Figure 2.

Figure 2.

Figure 2.

Figure 2.

Figure 3.

Figure 3.

Figure 3.

Figure 3.

Finally, we made sensitivity analyses, with changing assumptions within the model. This additional material is presented in the Appendix.

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DISCUSSION

We provide calculations for pediatric hospital beds and PICU capacity for an influenza pandemic for one region in The Netherlands, showing that even during the peak of the pandemic, hospital facilities can continue to provide adequate healthcare service to the public. As a novel element, we include calculations for HCW absenteeism. We have not considered potential erosion of professionalism with increased absenteeism due to fear and panic among staff or due to staff members' caring for sick family members. Although morale was high during the severe acute respiratory syndrome outbreak in Singapore and Toronto (31), some examples of strained professional behavior have been reported (32). We believe that erosion of professionalism and morale may be partly preventable by implementing effective protection for HCWs (33, 34), with appropriate training to comply with protocols for personal protection. In our hospital protocol for management of patients of new pandemic influenza and of other high-risk respiratory pathogens, we have included extensive measures to separate these patients from other patients and focus on the protection of staff (1). Adherence to similar protocols has been shown to protect HCWs caring for patients with severe acute respiratory syndrome (34).

For a new pandemic, the important issues to factor in are magnitude and duration, calculation of staff shortages, and the limited capacity to call in external resources.

We show that an influenza pandemic for children can be managed, even allowing emergency care for noninfluenza-related acute cases, especially when firm decision making rules are followed and antiviral therapy is used. With appropriate patient management, adequate health care can be provided even during the peak of the pandemic. We recognize the impact this may have on the pediatric clinicians and nurses who must make these decisions. Many clinicians now realize that end-of-life decisions are an integral part of health care (35–37) and can be considered independent of any specific religious background or culture (38). ICU staff in The Netherlands have been trained to take charge of decision processes about forgoing life support in the ICU (35). They are aware of potential difficulties in communicating with members of the ICU team, including medical, nursing, and technical staff in decisions at the end of life. The challenge during an outbreak of pandemic influenza will be in orchestrating and implementing these decisions under extreme time pressure. Relatives of patients as well as team members may need more time than is available to accept that some patients on life support who are not responding to treatment will not recover. Some may insist on continuation of support, although it would be unwise and possibly disrespectful to these patients to continue futile treatment and unfair to others who might have been saved if those resources had been available. A generous and time-consuming approach may not apply under the anticipated extreme conditions of pandemic influenza. Decision making rules have to be adapted to real-time information updates obtained during the course of the pandemic, and briefings and exchange of information throughout the pandemic crisis are pivotal. Our overall assessment that an influenza pandemic with assumptions described here can be managed at the level of healthcare institutions clearly contrasts with the sobering and daunting analysis presented for ICU capacity in the United Kingdom or Australasia (16, 21) and relates more closely to the developments observed in the evolving new influenza H1N1(v) (39–42).

There are several limitations to our analysis. We based our model on incomplete and sometimes conflicting or inconsistent information on the impact of an influenza pandemic. We assume that more reliable data will only become available when the pandemic is in progress. The effect of antiviral medications, vaccination campaigns, and, for instance, closure of schools and airports may alter the key characteristics of the pandemic, all having the effect that onset is delayed and that the course is more protracted, with a much lower peak (14). Even a less-than-perfect vaccine might have a tremendous impact on the course of the pandemic. The need for surge capacity of hospital resources is more dependent on the combination of excess hospital admissions and length of stay than on the mere number of hospital admissions. The small percentage of children admitted to the hospital in our model (based on past experiences) implies that relatively small increases in admission rate will have a huge impact on hospital resources requirement. Another limitation to our study is using a cutoff point at 25 kg for children eligible for admission to an adult ICU. We acknowledge the immense pressure this would place on staff accustomed to caring for adults. If however, as can be observed from the development of the novel influenza H1N1(v), mortality in patients admitted to ICUs is lower (as might be expected based on the 1918–1919 influenza pandemic), a huge strain on already scarce surge capacity of hospital and intensive care beds could be expected (39–46). The recommendations of the Taskforce Influenza Dutch Society for Intensive Care (NVIC) to the Minister of Health in The Netherlands are drawn up by adult intensive care physicians, focusing attention on the care of children in an adult intensive care environment (24).

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CONCLUSIONS

We modeled pediatric surge capacity of healthcare facility and PICU requirements over time to assess the adequacy of preparedness planning for an influenza pandemic. PICU facilities will be a major limiting factor in healthcare provision for children but detailed analyses for needs and demands in PICU care have not been published. We show that PICU surge capacity is likely to be adequate, assuming that “older children” (age, >7–8 yrs) can be rerouted to an adult ICU environment preserving adequate bed space for “younger children,” that enough adult ICU resources are available, and that safe provision of care can be guaranteed. To this end, PICU physicians and nurses need to be prepared and trained to assist in order that care be delivered in adult surgical, medical, and mixed ICUs. PICU physicians and nusrses must also familiarize themselves with the adult ICU setting and environment; similarly, adult ICU physicians and nurses, as well as anesthesiologists, need to be prepared and trained to assist in order for care to be delivered in PICU environments.

We recommend that a model, with assumptions that can be adapted with new information obtained during early stages of an evolving pandemic, be an integral part of a preparedness plan for a pandemic influenza with new human transmissible agent like influenza A virus.

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REFERENCES

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9. World Health Organization: Pandemic (H1N1) 2009—Update 69: Laboratory-confirmed cases of pandemic (H1N1) 2009 as officially reported to WHO by States Parties to the International Health Regulations (2005) Available at http://www.who.int/csr/don/2009_07_01a/en/index.html. Accessed October 12, 2009
10. World Health Organization: Cumulative Number of Confirmed Human Cases of Avian Influenza A/(H5N1) Reported to WHO. Available at http://www.who.int/csr/disease/avian_influenza/country/cases_table_2009_07_01/en/index.html. Accessed July 22, 2009
11. Nicoll A: Human H5N1 infections: So many cases—Why so little knowledge? Euro Surveill 2006; 11:74–75
12. The American Academy of Pediatrics (AAP) and Trust for America's Health (TFAH): Pandemic influenza: Warning, children at-risk. Elk Grove Village, IL: AAP; 2007
13. Writing Committee of the Second World Health Organization Consultation on Clinical Aspects of Human Infection with Avian Influenza A (H5N1) Virus, Abdel-Ghafar AN, Chotpitayasunondh T, et al: Update on avian influenza A (H5N1) virus infection in humans. N Engl J Med 2008; 358:261–273
14. Ferguson NM, Cummings DAT, Fraser C, et al: Strategies for mitigating an influenza pandemic. Nature 2006; 442:448–452
15. Gruber PC, Gomersall CD, Joynt GM: Avian influenza (H5N1): Implications for intensive care. Intensive Care Med 2006; 32:823–829
16. Menon DK, Taylor BL, Ridley SA: Modelling the impact of an influenza pandemic on critical care services in England. Anaesthesia 2005; 60:952–954
17. Kash J, Tumpey T, Proll S, et al: Genomic analysis of increased host immune and cell death responses induced by 1918 influenza virus. Nature 2006; 443:578–581
18. Ahmed R, Oldstone MBA, Palese P: Protective immunity and susceptibility to infectious diseases: Lessons from the 1918 influenza pandemic. Nat Immunol 2007; 8:1188–1193
19. Doherty PC, Turner SJ, Webby RG, et al: Influenza and the challenge for immunology. Nat Immunol 2006; 7:449–455
20. Woods CR, Abramson JS: The next influenza pandemic: Will we be ready to care for our children? J Pediatr 2005; 147:147–155
21. Anderson TA, Hart GK, Kainer MA: Pandemic influenza-implications for critical care resources in Australia and New Zealand. J Crit Care 2003; 18:173–180
22. Brundage JF, Shanks GD: Deaths from bacterial pneumonia during 1918–19 influenza pandemic. Emerg Infect Dis 2008; 14:1193–1199
23. Gupta RK, George R, Nguyen-Van-Tam JS: Bacterial pneumonia and pandemic influenza planning. Emerg Infect Dis 2008; 14:1187–1192
24. Taskforce Influenza Nederlandse Vereniging voor Intensive Care (NVIC) (Taskforce Influenza Dutch Society for Intensive Care): Richtlijn voor volwassenen Intensive Care afdelingen Influenza pandemie (Guidelines for adult Intensive Care departments Influenza pandemic). Ede, the Netherlands: NVIC; 2009
25. Biarent D, Bingham R, Richmond S, et al: European Resuscitation Council guidelines for resuscitation 2005. Section 6. Paediatric life support. Resuscitation 2005; 67(Suppl 1):S97–S133
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28. Hagenaars TJ, Van Genugten MLL, Wallinga J: Scenario analysis of transmission dynamics, health-care demand and mortality. In: Brief report to the Health Inspectorate of The Netherlands. Bilthoven, the Netherlands: RIVM; 2003; 1–9
29. Van Genugten MLL, Heijnen MLA, Jager JC: pandemic influenza and healthcare demand in the Netherlands: Scenario analysis. Emerg Infect Dis 2003; 9:531–538
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APPENDIX – PANDEMIC INFLUENZA and PEDIATRIC INTENSIVE CARE

This appendix includes sensitivity analysis. Models for estimating healthcare demands, incidence, and prevalence in different scenarios and after intervention strategies. In the models, the following assumptions were made:

  • Attack rates of 25%, 30%, and 50%.
  • The age-specific attack and complication rates are as they would be in a normal influenza epidemic.
  • Healthcare, including use of antimicrobial agents, would be equal to that of a normal influenza epidemic.
  • Therapeutic use of one treatment of neuraminidase inhibitors (administered within 48 hrs after onset of symptoms) gives a 50% reduction in hospital admissions and proportion of deaths.
  • No upper limit inhibitors shortage has been incorporated in models.
  • Total high-risk group per 100,000 inhabitants is based on registrations from databases of general practitioners.
  • Duration of the pandemic period is based on historical data, although local and regional differences in duration can occur.
  • Basic reproductive number R0 was set at 1.4.
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Formulae (adapted from Hagenaars et al [1] and Van Genugten et al [2])

TotPop = Total population divided into age and risk groups

PopatRisk = Population at risk

HCcmr Influenza-like illness = Number of general practitioner consultations per 100,000 inhabitants

ZHObaltussen = Number of hospital admissions per 100,000 inhabitants (adapted from Baltussen (3))

Ssprenger = Proportion of deaths attributable to influenza per 100,000 inhabitants (adapted from Sprenger (4))

HCrate = General practitioners' consultation rate for influenza-like illness

ZHOrate = Hospital admission rate for influenza

Srate = Mortality rate as a result of influenza

AR_Pandemic/Normal epidemic = Pandemic attack rates versus “normal” epidemic attack rates

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Formulae for Nonintervention Scenario

HCrate = HCcmr Influenza-like illness

ZHOrate = ZHObaltussen

Srate = Ssprenger

PopatRisk = TotPop

Number of general practitioner consultations = HCrate × PopatRisk ×

AR_Pandemic/Normal epidemic

Number of hospital admissions = ZHOrate × PopatRisk × AR_Pandemic/Normal epidemic

Mortality = Srate × PopatRisk × AR_Pandemic/Normal epidemic

All models are based on 0.3% hospital admission rate for infected patients. Changing this rate will have a significant impact on the peak demand for hospital beds and ICU beds. The maximum number of regular hospital beds in the 15 hospitals in the 3 northern provinces of the Netherlands equals 5629 of which 3940 could be made available for influenza-related hospital admissions (30% of all admissions are for acute, non-influenza-related care). The maximum number of ICU beds that could be made available for influenza-related care equals 136. The number of pediatric hospital beds in the UMCG is 100. The maximum number of pediatric intensive care beds that could be made available for influenza-related care equals 31.

In the next tables, we present the difference (i.e., surplus or deficit) between demand and capacity for ICU beds at the peak of the pandemic for a mean length of stay of 8 and 15 days with a maximum of 31 available PICU beds for different hospital admission rates and 30% attack rate.

For example: with a 0.3% hospital admission rate, 50% ICU admission rate, and a mean length of stay of 8 days and no intervention with antiviral medication (Appendix Table 21), a shortage of 33 PICU beds will occur at the peak of the pandemic. Restricting access to the PICU beds for children up to 7 or 8 years, a large part of the children aged 8 and over can be placed at ICU beds in the adult ICUs. For a short period of time this shortage can also be bridged by utilizing any form of respiratory support available in the hospitals (e.g., operating room ventilators, medical specialists, nurses, medical students).

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APPENDIX REFERENCES

1. Hagenaars TJ, Van Genugten MLL, Wallinga J: Scenario analysis of transmission dynamics, health-care demand and mortality. 2003 Sep 1. Report No.: Brief report to the Health Inspectorate of the Netherlands
    2. Van Genugten MLL, Heijnen MLA, Jager JC. Pandemic Influenza and Healthcare Demand in the Netherlands: Scenario Analysis. Emerg Infect Dis 2003; 9:531–538
      3. Baltussen RM, Reinders A, Sprenger MJW, et al: Estimating influenza-related hospitalization in the Netherlands. Epidemiol Infect 1998; 121:129–138
        4. Sprenger MJ, Mulder PG, Beyer WE, et al: Impact of influenza on mortality in relation to age and underlying disease, 1967–1989. Int J Epidemiol 1993; 22:334–340
          5. Anderson TA, Hart GK, Kainer MA: Pandemic influenza-implications for critical care resources in Australia and New Zealand. J Crit Care 2003; 18:173–180

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            Pediatric Critical Care Medicine
            Pandemic planning—Preparing for the expected*
            Fuhrman, BP
            Pediatric Critical Care Medicine, 11(2): 299-300.
            10.1097/PCC.0b013e3181d506bf
            PDF (409) | CrossRef
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            Keywords:

            pediatric healthcare preparedness plan; pandemic influenza; H1N1 influenza; pediatric intensive care unit

            ©2010The Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies